ARTICLE | doi:10.20944/preprints201912.0099.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: Leishmania; thiochromenes; benzothiopyrans; cytotoxicity
Online: 8 December 2019 (15:54:40 CET)
As a part of our ongoing effort in the search for promising antileishmanial agents based on the thiochroman scaffold, we prepared a series of substituted 2H-thiochromenes. Thirty-three compounds were evaluated against intracellular amastigotes forms of L. (V) panamensis. Twelve compounds were active with EC50 values lower than 40 μM, and among those three compounds displayed the highest antileishmanial activity with EC50 values below 10 uM. Cytotoxicity was determined against human U-937 macrophages; thus, compounds having electrophilic alkenes (α,β-unsaturated carbonyl, or nitriles) displayed the highest antileishmanial activity but also moderate to high cytotoxicities. Based on SAR analysis, compounds 8d and 10, which differ only in the hydroxy group at C4, were selected as the most promising compounds in this library because good antiparasitic activity and Selectivity Index.
ARTICLE | doi:10.20944/preprints201811.0137.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: Streptomyces; angucycline; saquayamycin; cytotoxicity
Online: 6 November 2018 (10:55:42 CET)
Four angucycline glycosides including three new compounds landomycin N (1), galtamycin C (2) and vineomycin D (3), and a known homologue saquayamycin B (4), along with two alkaloids 1-acetyl-β-carboline (5) and indole-3-acetic acid (6), were identified from the fermentation broth of an intertidal sediments derived Streptomyces sp. Their structures were mainly established by IR, HR-ESI-MS, 1D and 2D NMR techniques. Among the isolated angucyclines, saquayamycin B displayed potent cytotoxic activity against hepatoma carcinoma cells HepG-2, SMMC-7721 and plc-prf-5, with IC50 values 0.135, 0.033 and 0.244 μM respectively, superior to positive drug doxorubicin. Saquayamycin B treatment to SMMC-7721 cells led to the typical morphological signs of apoptosis in 4',6-diamidino-2-phenylindole (DAPI) staining experiment.
REVIEW | doi:10.20944/preprints202308.1927.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: nanoparticles; graphene; graphene oxide; cytotoxicity
Online: 29 August 2023 (09:15:58 CEST)
Graphene-based nanoparticles possess remarkable physiochemical properties, making them promising for diverse applications in biomedicine, agriculture, food, and industrial applications. These nanoparticles have also been used in the fight against COVID-19. Human and environmental exposure to graphene-based nanomaterials is increasing at an unprecedented rate. However, there is still a huge knowledge gap regarding its safety in clinical applications. The topic remains controversial; although several routes of degradation exist, the cytotoxicity of graphene-based nanoparticles has been demonstrated. Various factors that can influence the cytotoxicity of graphene-based materials are discussed. This review summarizes the physiochemical properties of graphene-based materials and critically examines the possible effects of graphene-based nanoparticles on the molecular level and adverse health outcomes. While oxidative stress-mediated cell damage has been proposed as a primary cytotoxicity mechanism for graphene-based materials, various in vivo biodistribution and cytotoxicity mechanisms are also highlighted. Therefore, this review of the literature provides an overview of the cytotoxicity of GBMs and raises concerns about their widespread application with potential hazardous consequences on the environment and human health.
ARTICLE | doi:10.20944/preprints202105.0459.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: bioactivity; phytochemistry; cytostatic, cytotoxicity; microalga
Online: 20 May 2021 (09:11:44 CEST)
New resources of food, pharmaceuticals or biotechnological products are needed. The huge biodiversity of aero-terrestrial lichen-symbiont microalgae remains unexplored. Viability of these for human consumption demands the demonstration of the absence of toxic effects. In vitro biocompatibility of crude homogenates of axenic microalga Asterochloris erici, symbiotic in the lichen Cladonia cristatella, was analyzed after treatment of cultured L929 fibroblasts with different doses of microalgal homogenates. The results show that crude homogenates of A. erici do not induce fibroblast cytotoxicity but seem to have some cytostatic effect inducing slight cell cycle alterations and intracellular reactive oxygen species (ROS) increase at the highest dose. Carotenoid analysis demonstrates high content of lutein, a xanthophyll with antioxidant and cytostatic properties in vivo. These findings confirm that Asterochloris erici can be considered suitable for the development of alimentary or pharmaceutical applications. The cytostatic effects should be further investigated for antitumor agents.
ARTICLE | doi:10.20944/preprints201810.0454.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: platinum iodido complexes; cytotoxicity; photoactivation
Online: 19 October 2018 (14:15:28 CEST)
Trans platinum complexes have been the landmark in unconventional drugs prompting the development of innovative structures that might exhibit chemical and biological profiles different to cisplatin. Iodido complexes made a new turning point in the platinum drug design field since their cytotoxicity was reevaluated and reported. In this new study, we have synthesized and evaluated diodido complexes bearing aliphatic amines and pyridines in trans configuration. X-ray diffraction support the structural characterization. Their cytotoxicity has been evaluated in tumor cell lines such as SAOS-2, A375, T-47D and HCT116. Moreover, we report their solution behavior and reactivity with biological models. UVA irradiation induces an increase in their reactivity towards model nucleobase 5´-GMP in early stages, and promotes the release of the pyridine ligand (spectator ligand) at longer reaction times. Density Functional calculations have been performed and the results are compared with our previous studies with other iodido derivatives.
ARTICLE | doi:10.20944/preprints202311.1599.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: Perilla frutescens; extracts; antioxidant; antitumoral; cytotoxicity
Online: 24 November 2023 (11:33:48 CET)
(1) Background: This study aimed to outline the antitumoral, antioxidant, and cytotoxic proprie-ties of various types of Perilla frutescens extracts obtained from the leaves of the species; (2) Methods: We determined total polyphenols, flavonoids and anthocyanins contents, as well as the in vitro antioxidant, antitumoral, and cytotoxic actions in 3 types of ethanolic extracts (E1, E2, E3) and in 3 types of ethanol: acetone extracts (A1, A2, A3) of Perilla frutescens according to standardized procedures; (3) Results: We found that Perilla frutescens ethanolic extracts had higher total phenol concentrations (p= 0.002). Flavonoids and anthocyanins concentrations were not statistically different between the two extracts. The iron chelating capacity, hydroxyl radical scavenging capacity, superoxide anion radical scavenging capacity, and lipoxygenase inhibition capacity showed a significant increase with higher concentrations of Perilla frutescens extracts, particularly the ethanolic extracts. Perillyl alcohol had greater cytotoxic capacity on MG-63 cell line and E1 extract showed similar significant cytotoxic effects on A431 cell line; (4) Conclusions: Both ethanolic and ethanol: acetone extracts from Perilla frutescens exhibited important antioxi-dant and antitumoral actions in vitro, which proportionally increased with concentration. The cytotoxic threshold determined in this study for various types of extracts could help determine the best dosage with the maximum antioxidant and antitumoral potential.
REVIEW | doi:10.20944/preprints202305.1910.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: organotin(iv); dithiocarbamate; synthesis; characterisation; cytotoxicity
Online: 26 May 2023 (10:02:12 CEST)
After Frankland first synthesized organotin compounds for the first time in 1849, their broad range of applications, including in industry and agriculture, resulted in a substantial increase in demand for organotin (IV) compounds after the 1940s. Because of the broad range of coordination numbers and molecular geometry that could result in numerous features, the structural diversity of organotin (IV) compounds is of great interest. Organotin (IV) dithiocarbamate has recently received attention as a therapeutic agent among organotin (IV) compounds. The hybrid complex individual properties of organotin (IV) and the dithiocarbamate moieties form a synergy of action stimulating increased biological activity. Organotin (IV) components have been shown in cytotoxicity studies to play a crucial role in cytotoxicity. Ligands serve to target and react to molecules while preventing unwanted changes in biomolecules. Organotin (IV) dithiocarbamate compounds have also been discovered to exhibit a broad range of cellular, biochemical, and molecular effects, with their toxicity largely determined by their structure. This review discusses the potential cytotoxicity effect of organotin(IV) dithiocarbamate, as well as its synthesis, elemental and spectroscopy analysis.
ARTICLE | doi:10.20944/preprints202305.1189.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: antioxidant; chlorogenic acid; caffeine; cytotoxicity; melanoidins
Online: 17 May 2023 (04:58:53 CEST)
: Coffee is one of the most consumed beverages in the world; its production is based mainly on varieties of the Coffea arabica species. Mexico stands out for its specialty and organic coffee. In Guerrero the production is given by small indigenous community’s cooperatives that market their product as raw material. Official Mexican Standards stipulate the necessary requirements for its commercialization within the national ter-ritory. In this work, the physical, chemical, and biological characterizations of green, medium, and dark roasted beans from C. arabica varieties were carried out. Analysis of HPLC showed higher chlorogenic acid (55 mg/g) and caffeine (1.8 mg/g) contents in the green beans of the Bourbon and Oro Azteca varieties. The caffeine (3.88 mg/g) and melanoidins (97 and 29 mg/g) contents increased according to the level of roasting; a dissimilar effect was found in the chlorogenic acid content (14.5 mg/g). The adequate nutritional content and the sensory evaluation allowed the classification of dark roasted as premium coffee (84.25 points) and the roasted medium as specialty coffee (86.25 points). The roasted coffees presented antioxidant activity without cytotoxic effect. The results obtained will serve as a basis for making decisions on the improvements of the coffees analyzed.
SHORT NOTE | doi:10.20944/preprints201712.0165.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: aromatic hydrazide condensation; phosphorus heterocycles; cytotoxicity;
Online: 25 December 2017 (07:00:47 CET)
5-Methyl-3,8-di-(2-amino-4-bromophenyl)-4,9-dioxa-1,2,6,7-tetraaza-5λ5-phosphaspiro[4.4]nona-2,7-diene was obtained in a condensation reaction of 2-amino-5-bromobenzohydrazide and methylphosphonyl dichloride in the presence of triethylamine. An initial biological screening was performed for the obtained product. The synthesized compound possesses two aromatic primary amine groups and two bromine atoms within the structure, which are suitable for further structural modifications.
ARTICLE | doi:10.20944/preprints202311.0087.v1
Subject: Chemistry And Materials Science, Polymers And Plastics Keywords: nanoplastics; nanoprecipitation; PET; surfactant; SDS; cytotoxicity; haemolysis
Online: 2 November 2023 (08:38:02 CET)
Manufactured nanoplastic particles (NPs) are indispensable for in vitro and in vivo testing and health risk assessment of this emerging environmental contaminant. High surface area and inherent hydrophobicity of plastic material, makes production of NPs devoid of any contaminants very challenging. In this study we produced nanoprecipitated polyethylene terephthalate (PET) NPs (300 nm hydrodynamic diameter) and characterized presence of ionic surfactant sodium dodecyl sulfate (SDS) by 1H NMR. Relative ratio of NP/surfactant was monitored on the basis of chemical shifts characteristic for PET and SDS. For a wide range of surfactant/NP ratio (1:17 to 1:1.2), measured zeta potential changed from -42.10 to -34.93 mV, but no clear differences were observed in cellular assays performed in protein-rich media on primary human cells. The remaining impurities contributed to the outcome of biological assays applied in protein-free buffers, such as human red blood cells hemolysis. As size, shape, zeta potential and contaminants of NPs may all be relevant parameters for biological effects of NPs, relative quantification of impurities exemplified in our work by application of 1H NMR for PET NPs and ionic surfactant SDS could be a valuable auxiliary method in quality control of manufactured NPs.
COMMUNICATION | doi:10.20944/preprints202306.2148.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: Curcumin-Copper (II); single crystal; cytotoxicity; antioxidant
Online: 29 June 2023 (13:26:13 CEST)
The first single crystal structure of the homoleptic copper (II) ML2 complex (M=Cu (II), L=curcumin) was obtained and its structure was elucidated by X-ray diffraction showing a square planar geometry. The supramolecular arrangement is supported by C-H···O interactions and the solvent (MeOH) plays an important role in stabilizing the crystal packing. The cytotoxic activity of the complex against six cancer cell lines substantially surpasses that of curcumin itself, and it is particularly selective against leukemia (K562) and human glioblastoma (U251) cell lines with similar antioxidant activity to BHT. This constitutes the first crystal structure of pristine curcumin complexed with a metal ion.
ARTICLE | doi:10.20944/preprints202305.1276.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: Paeonia suffruticosa; benzofuranones; cytotoxicity; NO production inhibition
Online: 18 May 2023 (05:26:34 CEST)
The Paeonia suffruticosa, called as 'Feng Dan', has been used for thousands of years in traditional Chinese medicine. In our chemical investigation on the root bark of the plant, five new phenolic dimers, namely paeobenzofuranone A‒E (1‒5), have been characterized. Their structures were determined by spectroscopic analysis including 1D and 2D NMR, HRESIMS, UV, and IR, as well as ECD calculations. Compounds 2, 4, and 5 showed cytotoxicity against three human cancer cell lines with IC50 values ranging from 6.7 to 25.1 μM. Compounds 1 and 2 showed certain inhibitory activity on NO production. To the best of our knowledge, the benzofuranone dimers and their cytotoxicity of P. suffruticosa are reported for the first time.
ARTICLE | doi:10.20944/preprints202111.0403.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: anticancer agent; cytotoxicity; cell viability test; QSAR
Online: 22 November 2021 (14:18:14 CET)
2-(Morpholin-4-yl)-4,5-bis(2’’,2’’,2’’-trinitroethoxy)-1,3,5-triazine having QSAR-predicted anti-tumor activity was tested for the cytotoxicity using MTT and LDH cell viability tests. The experiments were conducted using human fibroblasts, peripheral blood mononuclear cells and breast cancer cells and allowed to identify effective cytotoxic concentration ant therapeutic range of this compound. The data obtained suggest the feasibility of the further studies of the test compound as a potential anti-cancer agent.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: garlic; onion; antigenotoxicity; longevity; cytotoxicity; comet assay
Online: 25 March 2019 (10:09:47 CET)
This study aimed to evaluate the biological activities of two Allium species (Garlic and onion) as well as diallyl disulphide (DADS) and dipropyl disulphide (DPDS) as their representative bioactive compounds in a multi-assay experimental design. The genotoxic, antigenotoxic and lifespan effects of garlic, onion, DADS and DPDS were checked in Drosophila melanogaster and their cytotoxic, pro-apoptotic and DNA-clastogenic activities were analysed using HL60 tumoral cells. All compounds were non-genotoxic and antigenotoxic against H2O2-induced DNA damage with a positive dose-response effect and different inhibition percentages (the highest value: 95% for DADS) at all tested concentrations. Daily intake of Allium vegetables, DADS or DPDS had no positive effects on flies’ lifespan and healthspan. Garlic and DADS exerted the highest cytotoxic effects in a positive dose-dependent manner. Garlic and DADS exerted a DNA-internucleosomal fragmentation as an index of induced proapoptotic activity on HL60 cells. Allium vegetables and DADS were able to induce clastogenic strand breaks in the DNA of HL60 cells. This study showed the genomic safety of the assayed substances and their protective genetic effects against the hydrogen peroxide genotoxine. Long-term treatments during the whole life of Drosophila genetic model were beneficial only at low-median concentrations. The chemopreventive activity of garlic could be associated to its distinctive organosulphur DADS. We suggest that supplementary studies are needed to clarify the cell death pathway against garlic and DADS.
ARTICLE | doi:10.20944/preprints201812.0256.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Litsea cubeba; cytotoxicity; isolation and elucidation; lignans
Online: 21 December 2018 (04:55:35 CET)
Litsea cubeba, an important medicinal plant, is widely used as traditional Chinese medicine and spice. Using cytotoxicity-guided fractionation, nine new lignans (1-9) and eleven known analogues (10-19) were obtained from the EtOH extract of the twigs of L. cubeba. Their structures were assigned by extensive 1D and 2D NMR experiments, and the absolute configurations were resolved by specific rotation and a combination of experimental and theoretically calculated electronic circular dichroism (ECD) spectra. In the cytotoxicity assay, 7',9-epoxylignans with feruloyl or cinnamoyl group (7-9, 13 and 14) were selectively cytotoxic against NCI-H1650 cell line, while the dibenzylbutyrolactone lignans (17-19) exerted cytotoxicities against HCT-116 and A2780 cell lines. The results highlighted the structure-activity relationship importance of a feruloyl or a cinnamoyl moiety at C-9′ or/and C-7 ketone in 7',9-epoxylignans. Furthermore, compound 11 was moderate active toward protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 13.5 μM, and compounds 4-6, 11 and 12 displayed inhibitions against LPS-induced NO production in RAW264.7 macrophages, with IC50 values of 46.8, 50.1, 58.6, 47.5, and 66.5 μM, respectively.
ARTICLE | doi:10.20944/preprints201806.0386.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: essential oil; Psoralea corylifolia; cytotoxicity; encapsulation; solubilisation
Online: 25 June 2018 (12:00:52 CEST)
Babchi (Psoralea corylifolia) oil is an important essential oil used in several traditional medicines to cure various disorders. This phytotherapeutic agent possesses number of pharmacological activities including antibacterial, antifungal, antioxidant, anti-inflammatory, immunomodulatory and antitumor. However, volatile nature, poor stability and solubility of babchi oil (BO) restrict its pharmaceutical applications. Hence, the aim of the present work was to encapsulate this oil in β-cyclodextrin nanosponges (NS) in order to overcome above limitations. To fabricate nanosponges, β-cyclodextrin was crosslinked with diphenyl carbonate in different molar ratios viz.1:2, 1:4, 1:6, 1:8 and 1:10. The blank nanosponges were loaded with babchi oil using freeze-drying method. Particle size of the babchi oil loaded nanosponges was found to lie between 200-500 nm, with low polydispersity index. Further, zeta potential, Fourier transform infrared spectroscopy, X-ray diffraction, thermal analysis and electron microscopy were carried out for characterization of babchi oil nanosponges. Results obtained from spectral analysis ascertained the formation of inclusion complexes. Additionally, solubilisation efficiency of the babchi oil was checked in distilled water and found enhanced by 4.95 times with optimized β-cyclodextrin nanosponges. The cytotoxicity study was carried out by MTT assay using HaCaT cell lines. A significant improvement in photostability of essential oil was also observed by inclusion in nanosponges. Lastly, the optimized formulation was tested for antibacterial activity using Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Hence, encapsulation of BO in nanosponges resulted in efficacious carrier system in terms of solubility, photostability as well as safety of this oil along with handling benefits.
ARTICLE | doi:10.20944/preprints201804.0360.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: epoxide, cancer, anticancer, cytotoxicity, nucleotide excision repair
Online: 27 April 2018 (14:00:47 CEST)
Several clinically useful anticancer drugs selectively kill cancer cells by inducing DNA damage; the genomic instability and DNA repair defects of cancer cells make them more vulnerable than normal cells to the cytotoxicity of DNA-damaging agents. Because epoxide-containing compounds can induce DNA damage, we have used the MTT assay to evaluate the selective cytotoxicity of three epoxyalkyl galactopyranosides against A549 lung cancer cells and MRC-5 lung normal cells. Compound (2S,3S)-2,3-Epoxydecyl 4,6-O-(S)-benzylidene-β-D-galactopyranoside (EDBGP) showed the highest selective anticancer activity and was selected for mechanistic studies. After observing that EDBGP induced cellular DNA damage (comet assay), we found that cells deficient in nucleotide excision repair were hypersensitive to the cytotoxicity of this compound; this suggests that EDBGP may induce bulky DNA adducts. EDBGP did not inhibit glycolysis (glucose consumption and lactate production). Pre-treatment of lung cancer cells with several antioxidants did not reduce the cytotoxicity of EDBGP, thereby indicating that reactive oxygen species do not participate in the anticancer activity of this compound. Finally, EDBGP was screened against a panel of cancer cells and normal cells from several tissues, including three genetically modified skin fibroblasts with increasing degree of malignancy. Our results suggest that epoxyalkyl galactopyranosides are promising lead compounds for the development of new anticancer agents.
ARTICLE | doi:10.20944/preprints201711.0177.v2
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: Leishmania; thiochroman-4-ones; acyl hydrazone; cytotoxicity
Online: 2 January 2018 (10:11:55 CET)
Cutaneous leishmaniasis (CL) is a neglected tropical disease, which causes severe skin lesions. Due to the lack of effective vaccines, and toxicity or reduced effectiveness of available drugs in addition to complex and prolonged treatments, there is an urgent need to develop alternatives for the treatment for CL with different mechanisms of action. In our effort to search for new promising hits against Leishmania parasites we prepared 18 acyl hydrazone derivatives of thiochroman-4-ones. Compounds were evaluated for their in vitro antileishmanial activity against the intracellular amastigote form of Leishmania panamensis and cytotoxic activity against human monocytes (U-937 ATCC CRL-1593.2). Our results show that derivatization of the thiochroman-4-ones with acyl hydrazones significantly enhances the antileishmanial activity. Among the compounds tested semicarbazone and thiosemicarbazone derivatives of thioflavanone 19 and 20 displayed the highest antileishmanial activities, with EC50 values of 5.4 and 5.1 µM and low cytotoxicities (100.2 and 50.1 µM respectively), resulting in higher indexes of selectivity (IS).
ARTICLE | doi:10.20944/preprints202309.0803.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: Marine natural product; Sinularia nanolobata; Structure elucidation; Cytotoxicity
Online: 13 September 2023 (02:54:28 CEST)
Three new cembranoids (1–3) and a new casbanoid (4), along with three known analogues (5–7), have been isolated from the soft coral Sinularia nanolobata collected off Ximao Island. The structures including the absolute configurations of new compounds were established by extensive spectro-scopic data analysis, time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculations and the comparison with spectroscopic data of known compounds. In in vitro bioassay, compounds 1 and 5 exhibited moderate cytotoxic activities against human erythroleukemia (HEL) cells line with IC50 values of 37.1 and 42.4 uM, respectively.
REVIEW | doi:10.20944/preprints202308.2132.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: soft coral; Litophyton; secondary metabolites; terpenes; bioactivities; cytotoxicity
Online: 31 August 2023 (09:49:23 CEST)
Marine soft corals are prolific sources of various natural products that have served as a wealthy reservoir of diverse chemical scaffolds for new drug leads. The genus Litophyton contains almost 100 species but only a small part of them had been classified and chemically investigated, which calls for more attentions from the global researchers. In the current work, 109 secondary metabolites have been discussed based on published data from 1975 to July, 2023, covering a period of near five decades. The studied species of the genus Litophyton inhabited various tropical and temperate regions and afforded a variety of biologically active natural products such as terpenes, steroids, alkaloids, and lipids. A wide spectrum of pharmacological effects of these compounds had been evaluated, including cytotoxic, anti-HIV, antibacterial, antifungal, anti-malarial, antifeedant, molluscicidal, PTP1B inhibitory, and insect growth inhibitory activities. This review aims to provide an up-to-date literature survey and comprehensive insight into chemical structures, taxonomical distributions, and biological activities of the reported metabolites from the title genus whenever available.
ARTICLE | doi:10.20944/preprints202307.0678.v1
Subject: Biology And Life Sciences, Toxicology Keywords: environmental wear; uptake; cytotoxicity; ROS overproduction; mitochondrial dysfunction
Online: 11 July 2023 (07:17:51 CEST)
Airborne micro- and nanoplastics are widely spread and pose a risk to human health. The effects of virgin (v) and home oxidised (ox) nano- and micropolystyrene (nPS/mPS) (0.1 and 1 µm) were studied on the human alveolar cells (A549). Ox-nPS/mPS, simulating photoaging, allowed effects due to environmental wear to be assessed. Cellular uptake was quantified using FITC-functionalised nPS/mPS, while cytotoxicity, changes in the acidic compartment, ROS production, mitochondrial function and DNA damage were assessed to study the effects of internalised v- and ox-nPS/mPS. The uptake was dose-dependent and very fast, since, at the lowest dose, 20.8% and 21.8% of nPS and mPS, respectively, were internalised after 1 h. Compared to v-, significant ROS increases, DNA damage and mitochondrial impairment were observed after exposure to ox-nPS/mPS. The enhancement of effects due to environmental aging processes highlighted the true potential impact on human health of these airborne pollutants.
ARTICLE | doi:10.20944/preprints202306.1185.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: Apoptotic; Cytotoxicity; Green synthesis; Nanostructures; Scutellaria multicaulis; Silver
Online: 16 June 2023 (07:38:46 CEST)
Scutellaria multicaulis, a member of the Lamiaceae, is a medicinal plant indigenous to Iran, Afghanistan, and Pakistan. It has been widely used as a prominent herb in traditional medicine for thousands of years. This plant is reported with baicalein, wogonin, and chrysin flavonoids as a significant group of chemical ingredients, which can cure different diseases such as breast cancer. S. multicaulis leave extract was used for the bioreduction of silver nanoparticles (SmL-Ag-NPs), and their phytochemical contents and antioxidant, antibacterial, anti-proliferative, and apoptotic activity were evaluated. Optimal physicochemical properties of SmL-Ag-NPs were obtained by mixing 5% of leave extract and 2 mM of aqueous AgNO3 solution and confirmed by characterization studies including UV–visible spectrophotometry, FE-SEM, EDX, DLS, zeta potential, TGA, SERS, XRD and FTIR Spectroscopy. SmL-Ag-NPs exhibited higher content of TPC (Total Phenolic Content) and TFC (Total Flavonoid Content) and potential antioxidant activity. SmL-Ag-NPs also demonstrated dose-dependent cytotoxicity against MDA-MB231 cells multiplication with an IC50 value of 37.62 μg/mL at 48h through inducing cell apoptosis. This is the first report on the biosynthesis of silver nanoparticles using S. multicaulis leave extract, which can provide treatment for cancer diseases and reduce some negative effects of chemotherapy.
ARTICLE | doi:10.20944/preprints202208.0210.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: hydroxocobalamin; cyanocobalamin; thiolatocobalamins; thiol oxidation; ROS production; cytotoxicity
Online: 11 August 2022 (06:17:50 CEST)
Cobalamin is an essential nutrient required for the normal functioning of cells. Its deficiency can lead to various pathological states. Hydroxocobalamin (HOCbl) and cyanocobalamin (CNCbl) are the forms of vitamin B12 that are most commonly used for supplementation. There is substantial evidence indicating that cobalamins can both suppress and promote oxidative stress; however, the mechanisms underlying these effects are poorly understood. Here, it was shown that the oxidation of thiols catalyzed by HOCbl and CNCbl is accompanied by ROS production and induces, under certain conditions, oxidative stress and cell death. The form of vitamin B12 and the structure of thiol play a decisive role in these processes. It was found that the mechanisms and kinetics of thiol oxidation catalyzed by HOCbl and CNCbl differ substantially. It was discussed how these differences may explain different levels of ROS production and cytotoxicity induced by combinations of thiols with HOCbl and CNCbl. On the whole, the data obtained provide a new insight into the redox processes in which cobalamins are involved and might be helpful in developing new approaches to the treatment of some cobalamin-responsive disorders in which oxidative stress is an important component. In addition, these data may be useful for a better understanding of mechanisms underlying induction of different types of death of cancer cells and in a search for new targets for anticancer therapy.
ARTICLE | doi:10.20944/preprints202103.0237.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: graphene oxide; human keratinocytes; proliferation; gene expression; cytotoxicity
Online: 8 March 2021 (16:20:37 CET)
Few-layer graphene oxide (GO) has shown none or very weak cytotoxicity and anti-proliferative effects in a wide range of cell lines such as glyoma cells and human skin HaCaT cells, in concentrations up to 100 µg/mL However, multi-layer GO has been hardly explored in the biomedical field. Thus, multi-layer GO was examined here in human keratinocyte HaCaT cells treated with different concentrations ranging from 0.01 to 150 µg/mL during different periods of times (3, 12 and 24 hours). The results of this study showed a time-concentration dependence with two non-cytotoxic concentrations (0.01 and 0.05 µg/mL) and a median effective concentration value of 4.087 µg/mL at 24 hours of GO exposure. Contrary to what has been reported for few-layer GO, cell proliferation of the HaCaT cells in contact with the multi-layer GO at 0.01 μg/mL showed identical proliferative activity compared to an epidermal growth factor (1.6-fold greater than the control group) after 96 hours. The effects of the multi-layer GO on the expression of 13 genes (SOD1, CAT, MMP1, TGFB1, GPX1, FN1, HAS2, LAMB1, LUM, CDH1, COL4A1, FBN and VCAN) at the non-cytotoxic concentrations of GO in the HaCaT cells were analyzed after 24 hours. Thus, the lowest non-cytotoxic GO concentration was able to up-regulate the CAT, TGFB1, FN1 and CDH1 genes, which confirms the great potential of multi-layer GO in the biomedical field.
ARTICLE | doi:10.20944/preprints202009.0326.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: HepG2 cells; cytotoxicity; apoptosis; Hoechst staining; molecular dynamics
Online: 15 September 2020 (04:18:12 CEST)
The natural products and conventional chemotherapeutic drugs are believed to increase the cure rates of anti-cancer treatment while reducing their toxicity. The current study investigates the cytotoxic and apoptogenic effects of bioactive compounds from Monotheca buxifolia on Hep G2 cell lines. The effect on the viability of Hep G2 cells was evaluated by MTT assay; Morphological changes were studied, the apoptotic activity was demonstrated through Annexin-V-FITC/ PI, a molecular dynamics simulation study was conducted to explore the binding pattern of the compounds in the active site of the PPRAδ protein. The isolated compounds lauric acid, oleanolic acid, and bis(2-ethylhexyl) phthalate inhibited the growth of hepatocellular cancer cells, as determined by MTT assay and annexin V-FITC/PI. The IC50 value for lauric acid was 56.4584 ± 1.20 µg/ml, that for oleanolic acid was 31.9421 ± 1.03 µg/ml, and that for bis(2-ethylhexyl) phthalate was 83.8019 ± 2.18 µg/ml. After 24 h of treatment, 29.5% of Hep G2 cells treated with lauric acid, 52.1% of those treated with oleanolic acid, and 22.4% of those treated with bis(2-ethylhexyl) phthalate were apoptotic. Morphological assay and Hoechst staining microscopy revealed the morphological alterations of cell membrane accompanied by nuclear condensation after treatment. The high fluctuation indicates the high potency and adopting various interactions, and vice versa, the oleanolic acid showed highly residues fluctuation, which remains stable in the active site of PPARδ protein and involved in various interactions while remaining locally fluctuated in the binding site the other two compounds. In conclusion, a significant apoptogenic effect was exhibited by lauric acid, oleanolic acid, and bis(2-ethylhexyl) phthalate against HepG2 cells in inducing apoptosis. Our findings indicate that these bioactive compounds hold promise as potential therapeutic for hepatocellular carcinoma.
ARTICLE | doi:10.20944/preprints201805.0215.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: aziridine; cancer; cytotoxic; cytotoxicity; selectivity; nucleotide excision repair
Online: 15 May 2018 (09:00:29 CEST)
We recently screened a series of new aziridines β-D-galactopyranoside derivatives for selective anticancer activity and identified 2-methyl-2,3-[N-(4-methylbenzenesulfonyl)imino]propyl 2,3-di-O-benzyl-4,6-O-(S)-benzylidene-β-D-galactopyranoside (AzGalp) as the most promising compound. In this article, we explore possible mechanisms involved in the cytotoxicity of this aziridine and evaluate its selective anticancer activity using cancer cells and normal cells from a variety of tissues. Our data show that AzGalp induces DNA damage (detected with the comet assay). Cells deficient in the DNA repair pathway nucleotide excision repair (NER) were hypersensitive to the cytotoxicity of this compound. These results suggest that AzGalp induces bulky DNA adducts, and that cancer cells lacking a functional NER pathway may be particularly vulnerable to the anticancer effects of this aziridine. Several experiments revealed that neither the generation of oxidative stress nor the inhibition of glycolysis played a significant role in the cytotoxicity of AzGalp. The combinations of AzGalp with either oxaliplatin or 5-fluorouracil slightly improved the ability of both anticancer drugs to selectively kill cancer cells. AzGalp also displayed selective cytotoxicity against a panel of malignant cells versus normal cells; the highest selectivity was observed for two acute promyelocytic leukemia cell lines. Additional preclinical studies are necessary to evaluate the anticancer potential of AzGalp.
ARTICLE | doi:10.20944/preprints201804.0376.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Fusarium head blight; deoxynivalenol; cytotoxicity; Caenorhabditis elegans; RNAseq
Online: 29 April 2018 (10:40:16 CEST)
Deoxynivalenol (DON) is a mycotoxin produced by Fusarium spp. that causes Fusarium head blight (FHB) disease in cereal crops. Ingestion of food contaminated with DON poses serious human health complications. However, the DON cytotoxicity has been mostly deduced from animal studies. In this study, we used the nematode Caenorhabditis elegans (C. elegans) as a tractable animal model to dissect the toxic effect of DON. Our results indicate that DON reduces the fecundity and lifespan of C. elegans. The real-time RT-PCR analysis showed that DON upregulates innate immunity-related genes including C17H12.8 and K08D8.5 encoding PMK-1 (mitogen activated protein kinase-1)-regulated immune effectors, and F35E12.5 encoding a CUB-like domain-containing protein. Furthermore, our RNAseq data demonstrate that out of ~ 17,000 C. elegans genes, 313 are upregulated and 166 were downregulated by DON treatment. Among the DON-upregulated genes, several are ugt genes encoding UDP-glucuronosyl transferase (UGTs) which are known to be involved in chemical detoxification. The three upregulated genes, F52F10.4 (oac-32), C10H11.6 (ugt-26) and C10H11.4 (ugt-28) encoding the O-acyltransferase homolog, UGT26 and UGT 28, respectively, are shown to contribute to DON tolerance by RNAi bacterial feeding experiment. The results of this study provide insights to the targets of DON cytotoxicity and potential mitigation measures.
ARTICLE | doi:10.20944/preprints202309.1459.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: gold nanoparticles; Hallabong peel extract; green synthesis; colorimetric; cytotoxicity
Online: 21 September 2023 (07:42:37 CEST)
The utilization of gold nanoparticles (AuNPs) has garnered significant attention in recent times, particularly in the field of biomedical research. The utilization of AuNPs in chemical synthesis procedures raises apprehensions regarding their potential toxicity in living organisms, which is inconsistent with their purported eco-friendly and cost-effective aspects. In this investigation, AuNPs were synthesized via the green synthesis approach utilizing Jeju Hallabong peel extract (HPE), a typical fruit variety indigenous to South Korea. The visible-range absorption spectrum of gold nanoparticles from green synthesis (HAuNPs) that are red wine in color occurs at a wavelength of λ = 517 nm. The morphology and particle size distribution were analysed using transmission electron microscopy (TEM) and ImageJ software. The TEM images reveal that the HAuNPs exhibit a high degree of dispersion and uniformity in their spherical shape, with an average size of approximately 7 nm. Moreover, elevating the initial pH level of the mixed solution has an impact on the decrease in particle dimensions, as evidenced by the blue shift observed in the UV-visible spectroscopy absorbance peak. Elevating the reaction temperature may accelerate the synthesis duration. However, it does not exert a substantial impact on the particle dimensions. The outcomes of an avidin-biocytin colorimetric assay provide preliminary analyses of possible sensor tunability using HAuNPs. The cytotoxicity of HAuNPs was evaluated through in vitro studies using the MTT assay on RAW 264.7 cell lines. The results indicated that the HAuNPs exhibited lower cytotoxicity compared to both chemically reduced gold nanoparticles (CAuNPs) and commercially available gold nanoparticles (SAAuNPs).
ARTICLE | doi:10.20944/preprints202305.2097.v1
Subject: Engineering, Bioengineering Keywords: Cell viability; cytotoxicity; DLC coatings; genotoxicity; Tribocorrosion; Ti6Al4V; SS316L
Online: 30 May 2023 (09:29:55 CEST)
Stainless steel 316L (SS316L) and titanium-alloy Ti6AL4V exhibit properties for bio-medical applications; however their tribocorrosion associated with metallosis is still a major concern. Therefore smoothing DLC coatings aiming for the improvement of tri-bocorrosion and cell viability of stainless steel 316L (SS316L) and titanium-alloy Ti6AL4V with and without DLC coatings were compared. The motivation was due to many papers detailing metallosis caused by metal debris in the body's soft tissues. Nowadays, metallosis is responsible for almost of prosthesis replacement surgeries. DLC coatings were produced using the Plasma Enhanced Chemical Vapor Deposition (PECVD) technique; acetylene gas was used as a carbon precursor, and silane gas produced an amorphous silicon interface between the DLC coating and metal substrate. A combined setup of techniques thoroughly evaluated the coatings considering chemical composition, coatings adhesion at a metallic substrate, scratch resistance, and tribocorrosion susceptibility. The cytotoxicity and genotoxicity of metallic samples with and without DLC coatings were analyzed, considering cell viability and its correlation with coatings’ chemical composition
ARTICLE | doi:10.20944/preprints202305.1868.v1
Subject: Biology And Life Sciences, Biophysics Keywords: Plasmonic magnetoliposomes; Dual hyperthermia; Bovine lactoferrin; Cytotoxicity; Biological activity
Online: 26 May 2023 (05:40:34 CEST)
Bovine lactoferrin (bLf) is a milk-derived protein that exhibits multiple biological activities and has been explored towards different therapeutic applications. Since this molecule is susceptible to degradation and some of its properties depend on its tertiary structure, the encapsulation of bLf in stimuli-responsive therapeutic formulations provides an added value to potentiate its biological activities when administered. Plasmonic magnetoliposomes emerge as promising nanosystems for dual hyperthermia (magneto-photothermia) and local therapy, since the combination of magnetic and gold nanoparticles (NPs) in a single nanosystem (multifunctional liposomes) enables the targeting and controlled release of encapsulated drugs. In this work, plasmonic magnetoliposomes (PMLs) containing manganese ferrite nanoparticles (28 nm size) and gold nanoparticles (~ 5 nm size) functionalized with 11-mercaptoundecanoic acid or octadecanethiol, were synthesized and loaded with bLf. The structural, magnetic and optical properties of the nanoparticles were measured by TEM, SQUID and UV/vis/NIR absorption spectroscopy. Specific Absorption Rate was determined to assess the capabilities for magnetic and photothermal hyperthermia. Finally, Saccharomyces cerevisiae was used as an eukaryotic cellular model to assess the biological activity and the mechanism of entry of bLf-loaded PMLs, through counting of colony forming units and fluorescence microscopy, respectively. The results demonstrate that PMLs are mainly internalized through an energy- and temperature-dependent endocytic process, though the contribution of a diffusion component cannot be discarded. Most notably, only bLf-loaded PMLs exhibit cytotoxicity with an efficiency similar to free bLf, attesting their promising potential for bLf delivery in the context of therapeutic interventions.
ARTICLE | doi:10.20944/preprints202305.1220.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: ZnO; nanoparticle size; in vitro; cytotoxicity; hemolysis; protein corona
Online: 17 May 2023 (10:06:00 CEST)
This study describes a comparative in vitro study of the toxicity behavior of zinc oxide (ZnO) nanoparticles and micro-sized particles. The study aimed to understand the impact of particle size on ZnO toxicity by characterizing the particles in different media, including cell culture media, human plasma, and protein solutions (bovine serum albumin and fibrinogen). The study used various techniques such as atomic force microscopy (AFM), transmission electron microscopy (TEM), and dynamic light scattering (DLS) to characterize the particles and their interactions with proteins. Hemolytic activity, coagulation time, and cell viability assays were used to assess ZnO toxicity. The results highlight the complex interactions between ZnO NPs and biological systems, including their aggregation behavior, hemolytic activity, protein corona formation, coagulation effects, and cytotoxicity. Moreover, the study indicates that ZnO nanoparticles are not more toxic than micro-sized particles, and the 50 nm particles resulted in general the least toxic. Furthermore, the study found that at low concentrations, no acute toxicity was observed. Overall, this study provides important insights into the toxicity behavior of ZnO particles and highlights that no direct relationship between nanometer size and toxicity can be directly attributed.
ARTICLE | doi:10.20944/preprints202304.0545.v1
Subject: Medicine And Pharmacology, Dermatology Keywords: Paullinia cupana; natural products; nanoparticles; stability; cytotoxicity; cell culture
Online: 19 April 2023 (04:52:31 CEST)
The objective of this study was to analyze the in vitro stability and toxicity of liposomes containing guarana in skin cell lines. The liposomes were produced by the reverse phase evaporation method containing 1 mg/mL guarana. The stability of the liposomes was evaluated by physical-chemical parameters for up to 90 d using three different storage conditions. The cytotoxicity of guarana (GL), liposomes (B-Lip), and guarana-loaded liposomes (G-Lip) was evaluated on spontaneously immortalized human keratinocyte cell lines (HaCaT), murine swiss albino fibroblasts (3T3), and human fibroblast (1BR.3.G). The evaluation was performed using cellular viability analysis. The techniques used were 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red capturing (NRU) and the analyses were conducted after 24, 48, and 72 h exposure of these cells to the different treatments. The G-Lip exhibited physical-chemical stability for 60 d when the samples were stored in a refrigerator. The GL, B-Lip, and G-Lip demonstrated low cytotoxicity in the three cell cultures tested since a low reduction in cell viability was only observed at the highest concentrations. In addition, greater cell damage was observed for B-Lip; however, guarana protects cells from this damage. Thus, G-Lip structures can be considered as promising systems for topical applications.
ARTICLE | doi:10.20944/preprints202210.0171.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: EpCAM; breast cancer; antitumor activities; antibody‐dependent cellular cytotoxicity
Online: 12 October 2022 (10:08:42 CEST)
The epithelial cell adhesion molecule (EpCAM) is a stem cell and carcinoma antigen, which mediates cellular adhesion and proliferative signaling by the proteolytic cleavage. In contrast to low expression in normal epithelium, EpCAM is frequently overexpressed in various carcinomas, which correlates with poor prognosis. Therefore, EpCAM has been considered as a promising target for tumor diagnosis and therapy. Using the Cell-Based Immunization and Screening (CBIS) method, we previously established an anti‐EpCAM monoclonal antibody (EpMab-37; mouse IgG1, kappa). In this study, we investigated the antibody‐dependent cellular cytotoxicity (ADCC), complement‐dependent cytotoxicity (CDC), and an antitumor activity by a defucosylated mouse IgG2a-type of EpMab-37 (EpMab-37-mG2a-f) against an EpCAM‐expressing breast cancer cell line (BT-474). EpMab-37-mG2a-f recognized BT-474 cells with a moderate binding-affinity [a dissociation constant (KD): 2.9x10-8 M] by flow cytometry. EpMab-37-mG2a-f exhibited ADCC and CDC for BT-474 cells by murine splenocytes and complements, respectively. Furthermore, administration of EpMab-37-mG2a-f significantly suppressed the BT-474 xenograft tumor development compared with the control mouse IgG. These results indicated that EpMab-37-mG2a-f exerts antitumor activities against the BT-474 xenograft, and could provide valuable therapeutic regimen for the breast cancers.
ARTICLE | doi:10.20944/preprints202112.0263.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: anti-inflammatory; cytotoxicity; oxidative stress; phenolic compounds; sweet cherries
Online: 16 December 2021 (08:18:44 CET)
Cherries have been largely investigated due to their high content in phenolics in order to fully ex-plore their health-promoting properties. Therefore, this work aimed to assess, for the first time, the anti-inflammatory potential of phenolic-targeted fractions of Saco cherry, using RAW 264.7 mac-rophages stimulated with lipopolysaccharide. Additionally, the cytotoxic effects on gastric ade-nocarcinoma (AGS), neuroblastoma (SH-SY5Y) and normal human dermal fibroblast (NHDF) cells were evaluated, as well as the ability to protect these cellular models against induced oxidative stress. The obtained data revealed that cherry fractions can interfere with cellular nitric oxide (NO) levels by capturing NO radicals and decreasing inducible nitric oxide synthase and cyclooxygen-ase-2 expression. Furthermore, it was observed that all cherry fractions exhibited dose-dependent cytotoxicity against AGS cells, presenting cytotoxic selectivity for these cancer cells when compared to SH-SY5Y and NHDF cells. Regarding their capacity to protect cancer cells against oxidative injury, in most assays, the total cherry extract was the most effective. Overall, this study reinforces the sweet cherries incorporation in new pharmaceutical products, smart foods and nutraceuticals.
REVIEW | doi:10.20944/preprints202001.0301.v1
Subject: Biology And Life Sciences, Biophysics Keywords: electromagnetic fields; mutagenicity tests; cytotoxicity; magnetic phenomena; biophysical phenomena
Online: 26 January 2020 (01:57:22 CET)
Modern life implies a constant exposure of living organisms to electromagnetic fields generated by human made technology. The question of whether or not electromagnetic fields in the non-ionizing frequency range can affect cellular functions, increasing the risk of cancer or another pathologies is currently a subject of interest for scientific community of several disciplines of physics, biology, chemistry and medicine. The first part of this short review presents briefly the possible mechanism of interaction of electromagnetic fields in cellular level based in theoretical models and experimental results. The second part refers to experimental observations published by several authors about the potential cytotoxic and genotoxic effects of electromagnetic fields. Results of researches are no yet conclusive enough to accept or reject the genotoxic, carcinogenic or cytotoxic potential of these fields. Up to date the International Agency for Research on Cancer (IARC) has classified the X, gamma and ultraviolet radiation as carcinogenic and the fields generated by radio frequencies as possibly carcinogenic.
REVIEW | doi:10.20944/preprints201906.0029.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: antitumour compounds; marine natural products; bioactivity; cytotoxicity; marine invertebrates
Online: 4 June 2019 (12:55:33 CEST)
Recent advances in sampling and novel techniques in drug synthesis and isolation have promoted the discovery of anticancer agents from marine organisms to combat this major threat to public health worldwide. Bryozoans, filter-feeding, sessile aquatic invertebrates often characterized by a calcified skeleton, are an excellent source of pharmacologically interesting compounds including well-known chemical classes such as alkaloids and polyketides. This review covers the literature for secondary metabolites isolated from marine cheilostome and ctenostome bryozoans that have shown potential as cancer drugs. Moreover, we highlight examples such as bryostatins, the most known class of marine-derived compounds from this animal phylum, which is advancing through anticancer clinical trials due to their low toxicity and antineoplastic activity. The bryozoan antitumour compounds discovered until now show a wide range of chemical diversity and biological activities. Therefore, more research focusing on the isolation of secondary metabolites with potential anticancer properties from bryozoans and other overlooked taxa covering wider geographic areas is needed for an efficient bioprospecting of natural products.
ARTICLE | doi:10.20944/preprints201904.0299.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: X-ray diffraction; bioactivities; cytotoxicity test; Anti-cancer activities
Online: 26 April 2019 (11:00:21 CEST)
Owing to fascinating applications of ZnO in modern devices, it is interesting to explore its more features for future devices. Hence, herein, we have synthesized the high quality ZnO spherical nanoparticles (SNPs) through a facile green synthesis route and robust structural and biomedical studies are carried out. Hexagonal phase with 93.2% crystallinity was confirmed through XRD analysis. ZnO nanoparticles were tested for their bioactivities both in vivo (acute cytotoxicity test) and in vitro (Anti-cancer activities on liver (HepG2) and cervical (Hela) cancer cell lines, stimulatory/inhibitory effects on normal rat splenic cells and hemolytic effects on red blood cells). Results showed that ZnO SNPs has no cytotoxic effects on vital organ like liver and has no hemolytic action on red blood cells. ZnO SNPs showed inhibitory consequence on normal rat splenic cells growth at all tested concentrations. ZnO nanoparticles showed an inhibitory effect on HepG2 cell line. While showed stimulatory effect on Hela cell line. Current study presents the synthesized ZnO SNPs as highly applicable in bio-optoelectronics.
ARTICLE | doi:10.20944/preprints201804.0282.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: aminosteroid; aminocycloartane; alkaloid; 3D-QSAR; CoMFA; antitrypanosomal activity; cytotoxicity
Online: 23 April 2018 (11:02:16 CEST)
As part of our research for new leads against human African trypanosomiasis (HAT), we report on a 3D-QSAR study for antitrypanosomal activity and cytotoxicity of aminosteroid-type alkaloids recently isolated from the African medicinal plant Holarrhena africana A. DC. (Apocynaceae), some of which are strong trypanocides against Trypanosoma brucei rhodesiense (Tbr) with low toxicity against mammalian cells. Fully optimized 3D molecular models of seventeen congeneric Holarrhena alkaloids were subjected to a comparative molecular field analysis (CoMFA). CoMFA models were obtained for both, the anti-Tbr and cytotoxic activity data. Model performance was assessed in terms of statistical characteristics (R2, Q2 and P2 for partial least squares (PLS) regression, internal cross-validation (leave-one-out) and external predictions (test set), respectively, as well as the corresponding SDEP and F-values). With R2=0.99, Q2=0.83 and P2=0.79 for anti-Tbr activity and R2=0.94, Q2=0.64, P2=0.59 for cytotoxicity against L6 rat skeletal myoblasts, both models were of good internal and external predictive power. The regression coefficients of the models representing the most prominent steric and electrostatic effects on anti-Tbr and for L6 cytotoxic activity were translated into contour maps and analyzed visually, allowing suggestions for possible modification of the aminosteroids to further increase the antitrypanosomal potency and selectivity. Very interestingly, the 3D-QSAR model established with the Holarrhena alkaloids also applied to the antitrypanosomal activity of two aminocycloartane-type compounds recently isolated by our group from Buxus sempervirens L. (Buxaceae), which indicates that these structurally similar natural products share a common SAR and, possibly, mechanism of action with the Holarrhena steroids. This 3D-QSAR study has thus resulted in plausible structural explanations of the antitrypanosomal activity and selectivity of aminosteroid- and aminocycloartane-type alkaloids as an interesting new class of trypanocides and may represent a starting point for lead optimization.
ARTICLE | doi:10.20944/preprints201706.0071.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: 8-prenylnaringenin; naringenin; cellular accumulation; glioblastoma; cytotoxicity; confocal microscopy
Online: 16 June 2017 (03:25:34 CEST)
Gliomas are one of the most aggressive and treatment-resistant types of human cancer. One of the most promising field in gliomas cancer therapy is identification and evaluation of anticancer properties of compounds found in plants i.a. naringenin (N) and 8-prenylnaringenin (8PN). The prenyl group seem to be crucial to the anticancer activity of flavones, which may lead to enhanced cell membrane targeting and thus increased intracellular activity. Unfortunately, 8PN content in hop cones is from 10 to 100 times lower compared to other flavonoids i.e. xanthohumol. In this study we used a simple method for the synthesis of 8PN from isoxanthohumol, via O-demethylation with high, 97% of the isolated yield. Cellular accumulation and cytotoxicity of naringenin and 8-prenylnaringenin in normal (BJ) and cancer cells (U-118 MG) were also examined. Obtained data indicated that 8-prenylnaringenin exhibited higher toxicity against used cell lines than naringenin and both flavones inhibited stronger glioblastoma U-118 MG cells than normal fibroblasts. The anticancer properties of 8PN correlated with its significantly greater (37%), accumulation in glioblastoma cells than in normal fibroblasts. Additionally, naringenin indicated higher selectivity for glioblastoma as it was over 6 times more toxic for cancer than normal cells. Our results provide evidence that examined prenylated and non-prenylated flavanones have different biological activity against normal and cancer cell lines and this phenomenon may be useful in clinical practice to construct new, anticancer drugs for glioblastoma.
ARTICLE | doi:10.20944/preprints201705.0100.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: cancer; carotenoid; chemoprevention; Cucurbita; cytotoxicity; DNA-protection; tumor cells
Online: 11 May 2017 (17:31:47 CEST)
Zucchini (Cucurbita pepo subsp. pepo) is a seasonal vegetable with high nutritional and medical value. Many useful properties of this fruit are attributed to its bioactive compounds. Zucchini fruits (“Yellow” and “Light Green” varieties) and four distinctive components (lutein, β-carotene, zeaxanthin and dehydroascorbic acid)were selected. Firstly it was determinated the lutein, β-carotene, zeaxanthin and dehydroascorbic acid content in these fruits and then, in order to measure the safety and suitability of their use different assays were carried out: (i) Genotoxicity and antigenotoxicity tests to determine the safety and DNA-protection against hydrogen peroxide; (ii) cytotoxicity and (iii) DNA fragmentation assay to evaluate the proapoptotic effect. Results showed that: (i) all the substances were non-genotoxic, (ii) all the substances were antigenotoxic except the highest concentration of lutein, (iii) “Yellow” Zucchini epicarp and mesocarp exhibited the highest cytotoxic activity (IC50 > 0.1 mg/mL and 0.2 mg/mL, respectively) and iv) “Light Green” Zucchini skin and pulp induced internucleosomal DNA fragmentation . To sump up, Zucchini fruit could play a positive role in human health and nutrition due to this fruit and its components were safe, able to inhibit significantly the H2O2-induced damage and exhibit antiproliferative and pro-apoptotic properties toward HL60 tumour cells. The information generated from this research should take into account to select potential accessions for breeding programs purposes.
ARTICLE | doi:10.20944/preprints202311.0711.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: antifungal potential; naphthoquinone derivatives; 2,3-DBNQ; fungal membrane permeability; cytotoxicity
Online: 13 November 2023 (08:25:22 CET)
The increase in fungal infections, accompanied by adverse effects and acquired resistance associated with the use of antifungal agents used for their clinical management, have facilitated the search for new substances with antifungal properties. Naphthoquinones have been investigated due to their multiple biological activities, including their significant antifungal potential. This study aimed at evaluating the antifungal potential of naphthoquinones against opportunistic fungi and dermatophytes and to assess the impact of a selected naphthoquinone on the formation of the cell wall, ergosterol membrane, and cellular membrane of Candida albicans ATCC 60193. Additionally, cytotoxicity in the MRC-(Medical Research Council-)5 cell lineage, Artemia salina, and tomato as well as arugula seeds was evaluated. The antifungal activity of four naphthoquinones was assessed using well-characterized fungal strains, the minimum inhibitory concentration (MIC) was determined applying the microdilution assay technique. Antifungal activity of the assessed naphthoquinones could be confirmed, particularly for 2,3-DBNQ (2,3-dibromo-1,4-naphthoquinone), which showed prominent antifungal activity (MIC of <1.56 - 6.25 µg/mL) in all chosen test settings. However, its toxicity in MRC-5 cells (IC50 = 15.44 µM), a recorded 100% mortality in A. salina at a concentration of 50 µg/mL, as well as inhibition of 94.8% of the tomato seeds at a concentration of 400 µg/mL and inhibition of 64.1% of arugula seeds at a concentration of 200 µg/mL may limit hypothetical therapeutic applications. It was demonstrated that the likely mechanism of action of 2,3-DBNQ involves interfering with fungal membrane permeability, leading to increased leakage of nucleotides. This study adds to available knowledge on antifungal effects of naphthoquinones, especially of 2,3-DBNQ, against opportunistic yeasts and dermatophytes. However, the observed cytotoxicity in the MRC-5 cell lineage, A. salina, as well as tomato and arugula seeds highlights a need for further research to optimize the selectivity and safety profile of naphthoquinones like 2,3-DBNQ before potential clinical use may be assessed.
ARTICLE | doi:10.20944/preprints202311.0492.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: microwave; ultrasound; saponins; carbohydrates; polyphenols; antioxidant activity; in vitro cytotoxicity.
Online: 7 November 2023 (17:01:04 CET)
Phytochemicals from Hedera helix L. lead to extracts with good biological properties which are beneficial to human health and can be used to protect plants against different diseases. The aim of this research was to find the most suitable extraction method and the most favorable parameters for different bioactive compounds extraction from ivy leaves. Different extraction methods, namely microwave assisted extraction (MAE), ultrasound assisted extraction (UAE), and conventional heating extraction (CHE), were used. The most suitable method for saponins extraction is MAE with an extraction efficiency of 58%, while for carbohydrates and polyphenols the best results were achieved by UAE with an extraction efficiency of 61.7% and 63.5%, respectively. The antioxidant activity (AA) of the extracts was also determined. The highest AA was obtained by UAE (368.98±9.01 µmol TR/gDM). Better results were achieved at 50 °C for 10 min of extraction, using 80% ethanol in water as solvent. In order to evaluate their in vitro cytotoxicity, the extracts richest in bioactive compounds were tested on NCTC fibroblasts. Their influence on the DNA content of RAW 264.7 murine macrophages was also tested. Until 200 µg/mL, the extracts obtained by UAE and MAE were cytocompatible with NCTC fibroblasts at 48 h of treatment.
ARTICLE | doi:10.20944/preprints202309.1552.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: marine Aspergillus terreus; bioactive metabolites; antimicrobial; cytotoxicity; anti-coronavirus activities
Online: 22 September 2023 (10:07:13 CEST)
The recently reported microbial natural product N-benzoyl-tryptophane (1) along with twenty-two diverse known bioactive compounds were isolated from the marine Aspergillus terreus LGO13 after its re-cultivation using liquid culture fermentation. Structures of the isolated compounds were established on the basis of HR-ESIMS 1D/2D NMR spectroscopy, and comparison with literature data. The antimicrobial, cytotoxicity, and antiviral activities of the microbial extract and the obtained compounds were investigated using a set of microorganisms, cervix carcinoma KB-3-1, non-small cell lung cancer (NSCLC) A549, and coronavirus (SARS-CoV-2), respectively. Molecular docking (MD) simulation was employed to explore the theoretical targets of the isolated metabolites as anti-SARS-CoV-2 agents. Chaetominine (2) seemed to be a potential candidate against papain-like protease (PLpro), one of the viral proteins being aimed by recent research as a possible target of anti-covid agents. Inspired by the MD results, we accordingly assessed the antiviral efficacy of chaetominine (2), fumitremorgin C (6), and azaspirofuran A (9) against SARS-CoV-2. Fumitremorgin C (6) showed a high selectivity index (SI = 20.3), while chaetominine (2) and azaspirofuran A (9) showed moderate selectivity index (SI = 6.6 and 3.2, respectively). These results showed a promising antiviral activity of Fumitremorgin C against SARS-CoV-2 virus.
ARTICLE | doi:10.20944/preprints202307.0022.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: Silver/zinc oxide nanoparticles; Semiconductor; Microbial biosynthesis; Photodegradation; Cytotoxicity; Antibacterial
Online: 3 July 2023 (08:37:44 CEST)
The biological synthesis of nanoparticles has been emerging as an environmentally benign and eco-friendly method owing to its cost-effectiveness and high efficiency. Recently, the biological synthesis of semiconductor and metal-doped semiconductor nanoparticles with enhanced photocatalytic degradation efficiency and anticancer and antibacterial properties have gained tremendous attention. In pursuit of this purpose, for the first time, we biosynthesized zinc oxide (ZnO) and silver/ZnO nanocomposites (NCs) as semiconductor and metal-doped semiconductor nanoparticles, respectively, using the cell-free filtrate (CFF) of Lysinibacillus sphaericus bacterium. The biosynthesized ZnO and Ag/ZnO were characterized by various techniques such as ultraviolet-visible spectroscopy, X-ray diffraction, Fourier-transform Infrared spectroscopy, Field-emission scanning electron microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The photocatalytic degradation potential of these semiconductor/metal-semiconductor nanoparticles was evaluated against the degradation of azo dye methylene blue (MB) under simulated solar irradiation. Ag/ZnO showed 90.7 ± 0.91% photocatalytic degradation of MB, compared to 50.7 ± 0.53% by ZnO in 120 min. The cytotoxicity of ZnO and Ag/ZnO on human cervical HeLa cancer cells was determined using an MTT assay. Both nanomaterials exhibited cytotoxicity in a concentration-dependent and time-dependent manner on HeLa cells. The antibacterial activity was also determined against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus). Compared to ZnO, Ag/ZnO NPs showed higher antibacterial activity. Hence, the biosynthesis of semiconductor nanoparticles could be a promising strategy for developing hybrid metal/semiconductor nanomaterials for different biomedical and environmental applications.
ARTICLE | doi:10.20944/preprints202306.1327.v1
Subject: Public Health And Healthcare, Public, Environmental And Occupational Health Keywords: Ultrafine Particles (UFPs); Air-Liquid Interface (ALI); Cytotoxicity; Exposure assessment.
Online: 19 June 2023 (09:50:50 CEST)
Previous research via cell experiments has shown that ultrafine particles (UFPs, particles less than 100 nm) emitted from Three-Dimensional desktop printers (3D printers) had cytotoxicity. However, a few particles from different filaments and their cytotoxicity combinations have been tested. Here we quantify emissions of UFPs and use Air-Liquid Interface (ALI) from one commercially available filament extrusion desktop 3D printer utilizing three different filaments by controlled experiments. A549 cells were exposed at the ALI to UFPs generated by a working 3D printer for an average of 45 minutes and 90 minutes. Twenty-four hours after exposure, cells were analyzed for percent cytotoxicity grown on the 24-well ALI insert (LDH assay). UFP exposure resulted in decreased cell viability (significantly increased LDH levels). The result shows that Acrylonitrile butadiene styrene (ABS) has the most significant particle emission. ALI exposures enable in vitro testing of mixtures of particles such as UFP from a 3D printer. ABS is the only filament with a significant difference compared with the HEPA control in 90 minutes of exposure (p-value <0.05). ABS and PETG we used during the experiment presented a significant difference compared with the HEPA control in 45 minutes of exposure.A screening analysis of potential exposure to these products in a typical environment suggests caution should be used when operating many printer and filament combinations in poorly ventilated spaces or without the aid of combined gas and particle filtration systems.
ARTICLE | doi:10.20944/preprints202305.1200.v1
Subject: Medicine And Pharmacology, Pulmonary And Respiratory Medicine Keywords: Histones; COPD; HDAC; H3.3; Inflammation; Hyperacetylations; Cytotoxicity; Alveolar damage; Cytokines.
Online: 17 May 2023 (05:46:03 CEST)
Excessive extracellular histones can damage cells despite their importance in DNA structure and gene regulation. We previously showed the harmful effect of histone 3.3 (H3.3) and its acetylated form (AcH3.3) in chronic obstructive pulmonary disease (COPD), but further research is needed to understand the in vivo underlying mechanisms. To investigate this, we administered a single dose of recombinant histones via intra-tracheal instillation in C57BL/6 mice and analyzed the outcomes after 48 hours. Both rH3.3 and rAcH3.3 effectively reached the bronchial and alveolar space. Lung histology revealed severe immune cell infiltration, rupture, damage, and thickening of many alveolar walls. Micro-CT scans showed macroscopic structure changes with a decreased tissue volume to total volume ratio. The administration of rH3.3 and rAcH3.3 induced lung apoptotic activity, as indicated by increased levels of cleavage caspase 3 and 9. Moreover, elevated plasma levels of pro-inflammatory cell mediators, including TNF-alpha, IL-6, MCP-3, and CXCL-1, were observed. The pathological changes and pro-inflammatory cytokine response were more pronounced in animals treated with rAcH3.3, which also exhibited leukocytosis and lymphocytosis. These findings emphasize the crucial role of extracellular H3.3 acetylation in inducing cytotoxicity and a robust, acute inflammatory response similar to what occurs in the lungs of COPD patients.
ARTICLE | doi:10.20944/preprints202206.0317.v1
Subject: Biology And Life Sciences, Aging Keywords: chick pea; chick pea water; apoptosis; cytotoxicity; colorectal cancer; polyphenols
Online: 22 June 2022 (11:50:20 CEST)
Chickpea is an essential legume, a staple food in many cultures and contains nutrients with potential health benefits. The chickpea water (CPW) leached out after cooking is usually discarded, which may potentially have significant anti-cancer and other health beneficial properties. This study compared the in-vitro bioactivity of CPW with chickpea polyphenol extract (CPPE) to evaluate its impact on pathways of colorectal cancer progression and development. Morphological observation by APOPercentage, cell viability detection using a cytotoxic assay and cell migration-scratch assay points to measure rate of metastasis were employed. Overall antioxidant activity of CPW and CPPE were measured using ABTS and DPPH free-radical assays. At 50 µg/mL concentration and above, both CPW and CPPE extracts significantly reduce cell viability in HT-29 colon cancer cell lines (p < 0.05). Moreover, a quantitative analysis of the extent of apoptosis demonstrated that at 250 and 500 μg/mL concentrations, both extracts induced significant apoptosis compared to the untreated control. Meanwhile, the cell migration scratch area decreases by 34.42% and 15.27% when treated with CPW and CPPE, respectively. In summary, CPW demonstrated comparable in vitro anti-cancer properties and antioxidant activity in colorectal cancer cells to CPPE. Further, in vivo studies are warranted to evaluate the physiological bioactivity of CPW and CPPE in targeting pathways of cancer development and progression
ARTICLE | doi:10.20944/preprints202109.0179.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: ovarian cancer; cannabis; phytocannabinoids; apoptosis; cytotoxicity; cell cycle; MAPK4; PARP1
Online: 9 September 2021 (11:57:38 CEST)
Ovarian cancer (OC) is the most lethal gynecologic malignancy. Cannabis sativa is being used to treat different medical conditions. We sought to examine the effectiveness of combinations of cannabis compounds against OC. Cytotoxic activity was determined by XTT assay on HTB75 and HTB161 cell lines. Apoptosis and cell cycle were determined by fluorescence-activated cell sorting (FACS). Gene expression was determined by quantitative PCR. The two most active fractions, F5 and F7, from a high Δ9–tetrahydrocannabinol (THC) cannabis strain extract and their standard mix (SM) showed cytotoxic activity against OC cells. The most effective phytocannabinoid combination was THC+cannabichromene (CBC)+cannabigerol (CBG). F5, F7 and SM affected cell cycle, led to cell apoptosis and to a marked reduction in cell migration. Moreover, these fractions act in synergy with niraparib, and were ~50 fold more cytotoxic to OC cells than to normal keratenocytes. Niraparib+F7 treatment was effective on OC patient's cells. F7 and the niraparin+fraction (F5 and F7) treatments reduced Mitogen-Activated Protein Kinase 4 (MAPK4) gene expression; this reduction may act in synergy with the niraparib inhibition of Poly (ADP-ribose) polymerase 1 (PARP1) activity. Combinations of cannabis compounds and niraparib should be examined for efficacy in pre-clinical studies and clinical trials.
ARTICLE | doi:10.20944/preprints202105.0185.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: Bioresorbable implants; Magnesium alloy; PHB; Biocompatibility; Cytotoxicity; NO; temporary implants
Online: 10 May 2021 (12:35:07 CEST)
Magnesium and its alloys are not normally used as bio-resorbable temporary implants due to their high and uncontrolled degradation rate in physiological liquid environment. The improvement of corrosion resistance to simulated body fluids (SBF) of a Magnesium alloy (AZ31) coated with poly-β-hydroxybutyrate (PHB) was investigated. Scanning electron microscopy, Fourier transform infrared spectrometer, and contact angle measurements were used to characterize surface morphology, material composition and wettability, respectively. pH modification of the SBF corroding medium, mass of Mg2+ ions released, and weight loss of the samples exposed to the SBF solution, and electrochemical experiment were used to describe the corrosion process and its kinetics. Materials biocompatibility was described by evaluating the effect of corrosion by products collected in the SBF equilibrating solution on hemolysis ratio, cytotoxicity, Nitric Oxide (NO), and total antioxidant capacity (T-AOC). The results showed that the PHB coating can diffusively control the degradation rate of Magnesium alloy improving its biocompatibility: hemolysis rate of materials was lower than 5%, while in vitro Human Umbilical Vein Endothelial Cells（HUVECs) compatibility experiments showed that PHB coated Mg alloy promoted cell proliferation and had no effect on the NO content, the T-AOC was enhanced compared with the normal group and bare AZ31 alloy. PHB coated AZ31 Magnesium alloy extraction fluids have a less toxic behavior due to the lower concentration of corrosion by-products deriving from the diffusion control exerted by the PHB coating films both from metal surface to the solution and vice versa. These findings provide more reference value for the selection of such system as tunable bioresorbable prosthetic materials
ARTICLE | doi:10.20944/preprints202012.0432.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: pomegranate; antioxidant capacity; membrane vesicles; cauliflower; keratinocytes; oxidative stress; cytotoxicity
Online: 17 December 2020 (12:05:42 CET)
Pomegranate extract (PG-E) has been reported to exert a protective effect in skin due to its antioxidant activity. Ingredients rich in phenolic compounds are unstable in extract solutions and, therefore, the use of a suitable nanosystem to encapsulate this type of extract could be necessary in different biotechnological applications. Thus, we investigated the capacity of Brassica oleracea L. (cauliflower) inflorescence vesicles (CI-vesicles) to encapsulate PG-E and determined the stability and the antioxidant capacity of the system over time. In addition, the protective effect against UV radiation and heavy metals in HaCaT cells was also tested. The CI-vesicles had an entrapment efficiency around 50% and accelerated stability tests did not show significant changes in the parameters tested. The results for the HaCaT cells show the non-cytotoxicity of the CI-vesicles containing PG-E and their protection against heavy metals (lead acetate and mercuric chloride) and UV-B radiation through a reduction of oxidative stress. The reduction of the percentage of deleted mtDNA (mtDNA4977, “common deletion”) in UV-treated HaCaT cells due to the presence of CI-vesicles containing PG-E indicates the mechanism of protection. Therefore, the effects of CI-vesicles loaded with PG-E against oxidative stress support their utilization as natural cosmeceuticals to protect skin health against external damage from environmental pollution and UV radiation.
ARTICLE | doi:10.20944/preprints201908.0006.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: chestnut shells; polyphenols; bioactive compounds; apoptosis; cytotoxicity; human cell lines
Online: 1 August 2019 (04:37:49 CEST)
In this study, bioactive compounds present in chestnut shells (CS) - derived from the industrial peeling processing - were extracted through different procedures. The aqueous extracts were characterized and the highest extraction yield and total phenolic content was obtained by Conventional Liquid Extraction (CLE). Gallic and protocatechuic acids were the main simple phenols in the extract with 86.97 and 11.20 mg/g chestnut shells dry extract (CSDE), respectively. Six tumor cell lines (DU 145, PC-3, LNCaP, MDA-MB-231, MCF-7 and Hep G2) and one normal prostate epithelial cell line (PNT2) were exposed to increasing concentration of CSDE (1-100 µg/mL) for 24 h and cell viability was evaluated using MTT assay. A reduced rate in cell viability was observed in DU 145, PC-3, LNCaP and MCF-7 cells while viability of MDA-MB-231 and Hep G2 cells was not affected except for PNT2 cells at a concentration of 100 µg/mL. Furthermore, CSDE-at concentrations of 55.5 and 100 µg/mL- lead to a significant increase of apoptotic cells in DU 145 cells of 28.2% and 61%, respectively. In conclusion, our findings showed that CS might be used for the extraction of several polyphenols that may represent good candidates for alternative therapies or in combination with current chemotherapeutics.
ARTICLE | doi:10.20944/preprints202310.1616.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: silver nanomaterials; activated carbon; infectious diseases; antibacterial mechanism of action; cytotoxicity
Online: 25 October 2023 (09:31:02 CEST)
In this study, we report the antibacterial mechanisms of action of uniform silver nanoparticles (AgNPs) and decorated activated carbon nanocomposite (CAC-AgNPs) obtained using a green synthesis approach. The nanomaterials were characterized by ultraviolet-visible (UV-vis) absorption spectra and Fourier transform infrared (FTIR) spectra. The antibacterial activity of the as-prepared nanomaterials was evaluated against an array of bacterial strains by microdilution method, whereas their cytotoxicity profile was evaluated on Vero cells (human mammalian cells). The antibacterial mechanistic studies of active nanomaterials were carried out through bacterial growth kinetics, nucleic acid leakage test, and catalase inhibition assay. A silver nanocomposite was successfully fabricated from Croton macrostachyus-based activated carbon. The as-prepared nanomaterials exhibited antibacterial activity against an array of bacterial strains (minimum inhibitory concentration (MIC) range: 62.5 to 500 µg/mL), the most susceptible being Escherichia coli and Staphylococcus aureus. Cytotoxicity studies of the nanomaterials on Vero cells revealed that the nanocomposite (median cytotoxic concentration (CC50): 213.6 µg/mL) was less toxic than the nanoparticles (CC50 value: 164.75 µg/mL) counterpart. Antibacterial mechanistic studies unveiled that the nanomaterials induced (i) bacteriostatic activity vis-à-vis E. coli and S. aureus and (ii) inhibition of catalase in these bacteria. This novel contribution on the antibacterial mechanisms of action of silver nanocomposite from C. macrostachyus-based activated carbon might contribute to the understanding of antibacterial action of these biomaterials. Nevertheless, more chemistry and in vivo experiments, as well as in depth antibacterial mechanistic studies are warranted for the successful utilization of these antibacterial biomaterials.
ARTICLE | doi:10.20944/preprints202305.0545.v1
Subject: Chemistry And Materials Science, Applied Chemistry Keywords: Wintergreen oil; niobium pentachloride; sequential reactions; antimicrobial activity; cytotoxicity; S. aureus
Online: 8 May 2023 (14:51:06 CEST)
Methyl Salicylate (MS), the principal constituent of Wintergreen oil (WO) was obtained from acetyl salicylic acid (ASA) by sequential transesterification-esterification reaction promoted by NbCl5for the first time. The reagents were added simultaneously, and the reaction process involved the transesterification and esterification reactions, which were accompanied by thin layer chromatography and gas chromatography. The conversion rate via GC was 100%, and the MS yield was 94%. A cytotoxicity of 50% and 64% for cultured S. aureus and metastatic melanoma cells, respectively, was observed for a concentration of 0.6 mg/mL, whereas no cytotoxicity for non-tumor cells was observed for this concentration, and it is considered to be the optimum concentration.
REVIEW | doi:10.20944/preprints202109.0488.v1
Subject: Biology And Life Sciences, Toxicology Keywords: Antioxidant activity; Reactive oxygen species; Medicinal plants; Cancer cell lines; Cytotoxicity
Online: 29 September 2021 (11:11:19 CEST)
This review article seeks to provide relevant information about the applicability of cell-based assays in assessing cytotoxicity of phytochemicals in light of several traditional methods available. Phenolic compounds and other phytochemicals are significant resources for drug discovery and development, thus underlining the enormous potentials of plant-derived natural products for the prevention and management of oxidative stress associated with cancer and other diseases. These effects have been linked to the content of phytochemicals such as phenolic compounds and their antioxidant properties. The abundance and complexity of these bio-constituents highlight the need for well-defined methods for the in vitro characterization and quantification of extracts and/or preparations that can translate to in vivo effects. Cell culture systems provide a useful model for basic research and a wide range of clinical in vitro studies and physiological processes as well as assessing the toxicity and therapeutic potential of compounds including plant extracts with potential medicinal benefits. Their use in cancer research provide a useful insight into possible therapeutic properties of phytochemicals at the cellular level. This approach has been instrumental in the initial stages of developing chemotherapeutic agents where human cancer cell lines are used as experimental models. These models have continued to contribute to elucidating specific requirements for certain biochemical events associated with proliferation, metabolism, loss of cell viability/apoptosis. Cell culture systems remain a promising tool in natural product development.
ARTICLE | doi:10.20944/preprints202109.0188.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: pyrazolo-pyrido-pyrimidines; cytotoxicity; tumor cell lines; SAR; in silico docking.
Online: 10 September 2021 (15:07:59 CEST)
To explore a new set of anticancer agents, a novel series of pyrazolo[4,3-e]pyrido[1,2-a]pyrimidine derivatives 7a-l have been designed and synthesized via cyclocondensation reactions of pyrazolo-enaminone 5 with a series of arylidene malononitriles; compound 5 was obtained from 5-amino-4-cyanopyrazole (3). The structures of the target compounds 7a-l were investigated by spectral techniques and elemental analysis (IR, UV-Vis, 1H NMR, 13C NMR and ESI-MS). All compounds were evaluated for their in vitro cytotoxicity employing a panel of different human tumor cell lines, A375, HT29, MCF7, A2780, FaDu as well as non-malignant NIH 3T3 and HEK293 cells. It has been found that the conjugate 7e was the most active towards many cell lines with EC50 values ranging between 9.1 and 13.5 µM, respectively. Moreover, in silico docking studies of 7e with six anticancer drug targets, i.e. DHFR, VEGFR2, HER-2/neu, hCA-IX, CDK6 and LOX also was performed, in order to gain some insights into their putative mode of binding interaction and to estimate the free binding energy of this bioactive molecule.
ARTICLE | doi:10.20944/preprints202105.0351.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: cytoprotection; cytotoxicity; ferns; oxidative stress; Polypodiaceae; Polypodium vulgare L.; medicinal plants
Online: 14 May 2021 (16:03:00 CEST)
Pteridophytes, represented by ferns and allies, are an important phytogenetic bridge between lower and higher plants (gymnosperms and angiosperms). Ferns have evolved independently of any other species in the plant kingdom being its secondary metabolism a reservoir of phytoconstituents characteristic of this taxon. The study of the possible medicinal uses of Polypodium vulgare L. (Polypodiaceae), PV, has increased particularly when in 2008 the European Medicines Agency published a monograph about the rhizome of this species. Thus, our objective is to provide scientific knowledge on the methanolic extract from the fronds of P. vulgare L., one of the main ferns described in the Prades Mountains, to contribute to the validation of certain traditional uses. Specifically, we have characterized the methanolic extract of PV fronds (PVM) by HPLC-DAD and investigated its potential cytotoxicity, phototoxicity, ROS production and protective effects against oxidative stress by using in vitro methods. Our results show that PVM is not cytotoxic against the different cell lines assessed, but we found potential cytoprotective and cellular repair activity in 3T3 fibroblast cells. This biological activity could be attributed to the high content of polyphenolic compounds; thus, this extract is positioned as a potential candidate for pharmaceutical uses.
ARTICLE | doi:10.20944/preprints201808.0123.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: HCT-116, WS1, water dispersive QDs, aqueous synthesis, cytotoxicity of QDs.
Online: 6 August 2018 (13:56:16 CEST)
Semiconductor nanocrystals or quantum dots (QDs), have unique optical and physical properties that make them potential imaging tools in biological and medical applications. However, concerns such as the aqueous dispersivity, toxicity to cells and stability in biological environments may limit the use of QDs in bioapplications. Here, we report an investigation into the cytotoxicity of aqueously dispersed CdSe(S) and CdSe(S)/ZnO core/shell QDs in the presence of human colorectal carcinoma cells (HCT-116) and a human skin fibroblast cell line (WS-1). The cytotoxicity of the precursor solutions used in the synthesis of the CdSe(S) QDs was also determined in the presence of HCT-116 cells and compared to that of the heat-shock protein (Hsp90) inhibitor, 17-AAG. CdSe(S) QDs were found to have a low toxicity at concentrations up to 100 µg/ml, with a decreased cell viability at higher concentrations, indicating a highly dose-dependent response. Meanwhile, CdSe(S)/ZnO core/shell QDs exhibited lower toxicity than uncoated QDs at higher concentrations. Confocal microscopy images of HCT-116 cells after incubation with CdSe(S) and CdSe(S)/ZnO QDs showed that the cells were stable in aqueous concentrations of 100 µg of QDs per ml, with no sign of cell necrosis, confirming the cytotoxicity data. Key words: HCT-116, WS1, water dispersive QDs, aqueous synthesis, cytotoxicity of QDs.
COMMUNICATION | doi:10.20944/preprints201802.0134.v1
Subject: Biology And Life Sciences, Virology Keywords: flavivirus; arbidol; umifenovir; antiviral activity; cytotoxicity; cell-type dependent antiviral effect
Online: 21 February 2018 (14:44:34 CET)
Arthropod-borne flaviviruses represent human pathogens of global medical importance, against which no effective small molecule-based antiviral therapy is currently available. Arbidol (umifenovir) is a broad spectrum antiviral compound approved in Russia and China for prophylaxis and treatment of influenza. This compound showed activity against numerous DNA and RNA viruses. Its mode of action is based predominantly on the impairment of critical steps of virus-cell interaction. Here we demonstrate that arbidol possesses a micromolar inhibition activity (EC50 values ranging from 10.57 ± 0.74 to 19.16 ± 0.29 µM) in Vero cells infected with Zika virus, West Nile virus, and tick-borne encephalitis virus, three medically important representatives of arthropod-borne flaviviruses. Interestingly, no antiviral effect of arbidol is observed in porcine stable kidney cells (PS), human neuroblastoma cells (UKF-NB-6), human hepatoma cells (Huh-7 cells) indicating that the antiviral effect of arbidol is strongly cell-type dependent. Arbidol presents a significant increasing in cytotoxicity profiles when tested in various cell lines in the order: Huh-7 < HBCA < PS < UKF-NB-6 < Vero with CC50 values ranging from 18.69 ± 0.1 to 89.72 ± 0.19 µM. Antiviral activity and acceptable cytotoxicity profiles suggest that arbidol could be a promising candidate for further investigation as a potential therapeutic agent in treating flaviviral infections.
ARTICLE | doi:10.20944/preprints201708.0060.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: Passiflora cincinnata Mast; redox activity; cell cytotoxicity; α-amylase inhibition; antihyperglycaemic
Online: 17 August 2017 (10:29:55 CEST)
Passiflora cincinnata Mast is a plant popularly used in traditional medicine in northeastern Brazil. The present study aimed to evaluate the anti-lipoperoxidative and anti-α-amylase properties, and cytotoxicity of an extract and fraction of passion fruit leaves (P. cincinnata Mast), as well as the antihyperglecemiant activity of the fraction rich in glycosylated flavonoids and showing low cytotoxicity in rats with a postprandial hyperglycaemia condition. The ethyl acetate fraction (F.ACT) of the P. cincinnata leaves presented the best anti-lipoperoxide properties with TBARs 81.49%, 95.48% and 75.62% lower than AAPH, FeSO4 and H2O2 induced controls, respectively, at 200 μg.mL-1. In addition, it presented an anti-α-amylase potential, with a better ability to inhibit the α-amylase enzyme in comparison to the acarbose control (IC50 6.49 ± 0.11 and 12.01 ± 0.4 μg.mL-1, respectively). The hydroalcoholic extract of P. cincinnata (ExEt) presented high content of total tannins, flavonoids and flavonols. However, F.ACT had the highest concentration of flavonoids among the fractions studied. HPLC analysis of this fraction revealed the presence of the flavonoids isovitexin, orientin and isoorientin. F.ACT showed low to no cytotoxicity below 150 μg.mL-1. Regarding the post-prandial antihyperglycaemic activity of F.ACT, it was observed at 50 and 100 mg.kg-1.
ARTICLE | doi:10.20944/preprints201703.0053.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: 1,3,4-Thiadiazole; 1,2,4-Triazole; synthesis; MTT assay; Cytotoxicity of Schiff base
Online: 10 March 2017 (10:11:56 CET)
5-(4-aminophenyl )-2-amino -1,3,4-thiadiazole was prepared by reaction of Thiosemicarbazide with 4-amino benzoic acid under reflux condition for 7 hours. The compound which has been synthesized successfully was subjected to addition reaction with 4-(Dimethylamino) benzaldehyde under reflux condition for 6 hours to synthesize Schiff bases. These compounds was characterized by using FTIR) and evaluated for their anticancer activity. The effect of (1, 3, 4-thiadiazole derivative) on the activity of malignant cells was studied by using different types of cell lines [Breast cancer, and human prostate cancer]. And was used the Electron microscope to show that the effect of the derivative on the cancer cells before and after 3 days of the injection time. It was found that the Schiff base of thiadiazole-1,3,4-(Dimethylamino)benzylidineamino]- [4-2-phenyl]amino was effective in reducing the size and density of malignant cells. That of 46.7 while in breast ) 145(DUprostate for growth inhibition produce of equal 85.9 µg/ml.
ARTICLE | doi:10.20944/preprints202304.0986.v1
Subject: Medicine And Pharmacology, Ophthalmology Keywords: Cytotoxicity; Limbal stem cells; Corneal healing; Mimicking reepithelization; Toxicity of MWCNT aggregates
Online: 26 April 2023 (12:33:39 CEST)
We have established earlier a cell line from the human limbal area to study cell growth and response to the toxic effects of antibiotics used in ophthalmology. In the recent work, the effect of multi-walled carbon nanotubes (MWCNTs) in cornea damage was investigated in vitro and in vivo in mice. In the in vitro experiments, the physiological effects of multi-walled carbon nano-tube (MWCNT) bundles on corneal wound healing were mimicked in vitro by a reepithelization limbal stem cell model. Murine in vivo experiments were performed with intact, non-functionalized MWCNTs to confirm the validity of in vitro tests. The MWCNTs of 10 -30 nm outer diameter at low concentration (5 µg/ml) did not interfere with the wound healing of the damaged limbal cell monolayer. Higher than 50 µg/ml concentrations: a) generated MWCNT aggregates, b) restrained the movement and prolonged the time of wound healing, c) increased the amplitudes of the oscillations of the cells, and d) resulted in scar formation affecting both cor-neal function and refraction. Chromatin condensation, a sensitive test of the viability of cells, including limbal stem cells revealed that the presence of a low concentration of nanotubes (5 µg/ml), did not significantly affect the viability of limbal cells. Chromatin condensation was completed and metaphase chromosomes were seen at higher MWCNT concentration proving that their aggregates did not affect the viability of limbal cells. This concentration of MWCNTs (5 µg/ml) did impact neither the reepithelization in vitro nor in vivo in the scratched eyes of mice. Scar formation took place at higher than 50 µg/ml concentrations and the healing of the cornea was prevented by the lack of movement of increasingly larger macroaggregates. In vivo murine experiments vali-dated in vitro monolayer regrowth followed by time-lapse microscopy portraying realistically the reepithelization of the damaged cornea that process was gradually slowed down by macro aggregate formation and caused the scarring of the cornea.
ARTICLE | doi:10.20944/preprints202304.0898.v1
Subject: Chemistry And Materials Science, Organic Chemistry Keywords: amphiphilic; monocatenar; bolaform; phenolic acids; rhamnosides; antioxidant; microwaves; eliciting properties; dermal cytotoxicity
Online: 25 April 2023 (07:30:20 CEST)
Symmetrical and dissymmetrical bolaforms were prepared with good to high yields from unsaturated L-rhamnosides and phenolic esters (ferulic, phloretic, coumaric, sinapic and caffeic) using two eco-compatible synthetic strategies involving glycosylation, enzymatic synthesis and cross-metathesis under microwaves activation. Furthermore, some of these new compounds present good eliciting properties depending on the carbon chain length and on the nature of the hydrophilic head. Their respective antioxidant activities have been also evaluated as well as their cytotoxic properties on dermal cells for cosmetic uses.
ARTICLE | doi:10.20944/preprints202301.0150.v2
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: oral; mucosa; mucins; tight junctions; wound-healing; E-liquids; cytotoxicity; viability; confluency.
Online: 3 April 2023 (03:33:37 CEST)
Background: Expansion of OKF6/TERT-2 oral epithelial cells in vitro is important for studying the molecular biology of disease and pathology affecting the oral cavity. Keratinocyte Serum-Free Medium (KSFM) is the medium of choice for this cell line. This study compares three media for OKF6/TERT-2 cultures: KSFM, Dulbecco’s Modified Eagle Medium/Nutrient Mixture of Hams F-12 (DMEM/F12) and a composite medium comprised of DMEM/F-12 and KSFM (1:1 v/v), referred as DFK. The toxicological effects of electronic cigarette liquids (E-liquids) on OKF6/TERT-2 cells cultured in these media were also compared. Methods: Cells were cultured in KSFM, DMEM/F12 or DFK and cellular morphology, growth, wound healing and gene expression of mucins and tight junctions were evaluated. Additionally, cytotoxicity was determined after E-liquid exposures. Results: Switching from KSFM to DMEM/F12 or DFK 24-hours post-seeding leads to typical cellular morphologies, and these cultures reach confluency faster than those in KSFM. Wound-healing recovery occurred fastest in DFK. Except for claudin-1, there is no difference in expression of the other genes tested. Additionally, E-liquid cytotoxicity appears to be amplified in DFK cultures. Conclusions: DMEM/F12 and DFK are alternative media for OKF6/TERT-2 cell culture to study molecular biology of disease and pathology, provided cells are initially seeded in KSFM.
ARTICLE | doi:10.20944/preprints202107.0390.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: Gold Nanorods; Theranostics; In vitro; Cancer; Cytotoxicity; CTAB; SDS; microCT; ICP-OES
Online: 16 July 2021 (16:36:52 CEST)
Due to their well-defined plasmonic properties, gold nanorods (GNRs) can be fabricated with optimal light absorption in the near-infrared region of the electromagnetic spectrum, which make them suitable for cancer-related theranostic applications. However, their controversial safety profile, as a result of surfactant stabilization during synthesis, limits their clinical translation. We report a facile method to improve GNR biocompatibility through the presence of sodium dodecyl sulfate (SDS). GNRs (120 x 40 nm) were synthesized through a seed-mediated approach, using cetyltrimethylammonium bromide (CTAB) as a cationic surfactant to direct the growth of nanorods and stabilize the particles. Post-synthesis, SDS was used as an exchange ligand to modify the net surface charge of the particles from positive to negative while maintaining rod stability in an aqueous environment. GNR cytotoxic effects, as well as the mechanisms of their cellular uptake, were examined in two different cancer cell lines, Lewis lung carcinoma (LLC) and HeLa cells. We not only found a significant dose-dependent effect of GNR treatment on cell viability but also a time-dependent effect of GNR surfactant charge on cytotoxicity over the two cell lines. Our results promote a better understanding of how we can mediate the undesired consequences of GNR synthesis byproducts when exposed to a living organism, which so far has limited GNR use in cancer theranostics.
ARTICLE | doi:10.20944/preprints202007.0180.v1
Subject: Medicine And Pharmacology, Pharmacy Keywords: Cationic cyclodextrin; cyclodextrin polymer; epichlorohydrin cross-linker; nasal delivery; cytotoxicity; cell uptake
Online: 9 July 2020 (08:05:35 CEST)
Cyclodextrin polymers have high applicability in pharmaceutical formulations due to better biocompatibility, solubility enhancement, loading capacity and controlled drug release than parent the cyclodextrins. The cytotoxicity and cell uptake of new cationic beta-cyclodextrin monomers and polymers were evaluated as suitable material for nasal formulations and their protective effects on cells exposed to hydrogen peroxide were studied. PC12 and CACO-2 cells were selected as the neuronal and epithelial type cells, respectively, to mimic the structure of respiratory and olfactory epithelia of the nasal cavity. All cationic beta-cyclodextrin polymers tested showed dose- and time-dependent toxicity; nevertheless, at 5 µM concentration and 60 min of exposure, the quaternary-ammonium-beta-cyclodextrin soluble polymer could be recognized as non-toxic. Based on these results, fluorescently labelled quaternary-ammonium-beta-cyclodextrin monomer and polymer were selected for uptake studies in CACO-2 cells. The monomeric and polymeric beta-cyclodextrins were internalized in the cytoplasm of CACO-2 cells; the cationic monomer showed higher permeability than the hydroxypropyl-beta-cyclodextrin, employed as comparison. Therefore, these cationic beta-cyclodextrins showed potential as excipients able to improve the nasal absorption of drugs. Furthermore, amino-beta-cyclodextrin and beta-cyclodextrin soluble polymers were able to reduce oxidative damage in PC12 and CACO-2 cells and thus could be studied as bioactive carriers or potential drugs for cells protection against oxidative stress.
ARTICLE | doi:10.20944/preprints202005.0019.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Barleria lupulina; cytotoxicity activity; MTT; NRU; ROS; MMP; THP-1 cell line
Online: 2 May 2020 (16:07:45 CEST)
Background: Barleria lupulina Lindl. (Hop-headed) is a small shrub, possess potent anti-inflammatory, analgesic, anti-leukemic, antitumor, anti-hyperglycemic, anti-amoebic, virucidal, diuretic, bactericidal and antibiotic properties. Methods: Cytotoxicity, bioactive assay and genetic analysis of B. lupulina were investigated in the present communication. The leaf extract was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), Neutral red uptake (NRU), DNA fragment, reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP) assay, gene expression analysis and cDNA synthesis to evaluate anti-cancerous potency using cancerous THP-1 cell lines in vitro and in vivo. Results: HPTLC analysis reveals four spots and GC-MS analysis displayed the presence of eleven bioactive compounds among which benzofuranon, hexadecanoic acid, ethyl 9,12,15-octadecatrienoate, and 3,7,11,15-tetramethyl-2-hexadecanoic acid were the most prominent compounds. The ethanolic extract showed significant cytotoxicity (P<0.5) against THP-1 cell line at a concentration of 1mg/mL. The cells were also observed for apoptosis through DNA fragmentation in B. lupulina treated cells. Conclusions: It can be concluded that if the dose range was further refined within the range of 100-1000 µg/mL there could be dose at which the entire population of the THP-1 cell line would be apoptosis induced. The extract induced ROS in the cells after 30 minutes of exposure displaying cytotoxic effects and DNA fragmentation assay.
ARTICLE | doi:10.20944/preprints202311.1586.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: Cardiac Magnetic Resonance; Cardiac Targeting Peptide; Human Cardiomyocyte Cells; Cytotoxicity; Cell Penetrating Peptides
Online: 26 November 2023 (06:03:36 CET)
Despite great strides in diagnosis and treatment, cardiac diseases remain the number one cause of mortality in the developed world, with rates catching up at an alarming rate in the developing world. Targeted delivery of therapeutics, specifically to cardiomyocytes, would open up new frontiers. Our prior work using a combinatorial in vitro and in vivo phage display methodology identified a 12-amino acid long peptide that targets cardiomyocytes selectively after an intravenous injection in as little as 5 mins, and hence was termed cardiac targeting peptide (CTP: APHLSSQYSRT). CTP has been used to deliver imaging agents, small drug molecules, photosensitizing nanoparticles, exosomes, and even miRNA to cardiomyocytes. As a natural extension for development of CTP as a clinically viable cardiac vector, we now present toxicity studies performed on the peptide. In vitro viability studies were performed in a human left ventricular myocyte cell line with 10µM of Cyanine-5.5 labeled CTP (CTP-Cy5.5). In vitro ion channel profiles were completed for CTP followed by more extensive studies performed by Eurofins in stably transfected cell lines for an extensive list of GPCR-coupled receptors. Positive data for GPCR-coupled receptors was interrogated further with RT-qPCRs performed on mouse heart tissue. In vivo studies consisted of pre- and post-blood pressure monitoring acutely after a single CTP (10 mg/Kg) injection. Further in vivo toxicity studies consisted of injecting 60, 6-week-old, wild-type CD1, male/female mice (1:1) injected with CTP (150 µg/Kg) intravenously. Mice were weighed immediately before injections and daily thereafter. Cohorts of mice were euthanized on day 0, 1, 2, 7 and 14 with inhalational CO2, followed by opening of the chest cavity, collection of blood via cardiac puncture, complete blood count analysis, metabolic profiling, and finally, liver, renal and thyroid studies. Lastly, mouse cardiac MRI was performed immediately before and after injections of CTP (150 µg/Kg) to assess changes in cardiac size or function. Human left ventricular cardiomyocytes showed no decrease in viability after a 30 min incubation with CTP-Cy5.5. In the Eurofins Cardiac Profiler Qube, no significant activation or inhibition of any of seventy-eight protein channels was observed other than OPRM1 and COX2 at the highest tested concentration, neither of which were expressed in mouse heart tissue as assessed by RT-qPCR. There was no change in blood pressures before and after injections with CTP at 10 mg/Kg. Blood counts and chemistries showed no evidence of significant hematological, hepatic or renal toxicities. Lastly, there was no significant difference in cardiac function, size or mass before and after CTP injections. Our studies with CTP showed no activation or inhibition of GPCR-associated receptors in vitro. We found no signals indicative of toxicity in vivo. Most importantly, cardiac functions remained unchanged acutely in response to CTP uptake. Further studies, in good laboratory practices fashion, are needed with more prolonged, chronic administration of CTP conjugated to a specific cargo of choice before human studies can be contemplated.
ARTICLE | doi:10.20944/preprints202305.1841.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: antibody-dependent cell-mediated cytotoxicity; ADCC; NK-92 cells; CD16A; CD107a; fucosylation; GA101
Online: 26 May 2023 (04:18:25 CEST)
Antibody-dependent cell-mediated cytotoxicity (ADCC) by natural killer (NK) lymphocytes eliminates cells infected with viruses. Antiviral ADCC requires three components: 1) antibody; 2) effector lymphocytes with the Fc-IgG receptor CD16A; and 3) viral proteins in infected cell membranes. Fc-afucosylated antibodies bind with greater affinity to CD16A than fucosylated antibodies; individuals’ variation in afucosylation contributes to differences in ADCC. Current assays for afucosylated antibodies involve expensive methods. We report an improved bioassay for antibodies that support ADCC which encompasses afucosylation. This assay utilizes externalization of CD107a by NK-92-CD16A cells after antibody recognition. We used anti-CD20 monoclonal antibodies, GA101 WT or glycoengineered (GE), 10% or ~50% afucosylated, and CD20-positive Raji target cells. CD107a increased detection 7-fold compared to flow cytometry to detect Raji-bound antibodies. WT and GE antibody effective concentrations (EC50s) for CD107a externalization differed by 20-fold, with afucosylated GA101-GE more detectable. The EC50s for CD107a-externalization vs. 51Cr cell death were similar for NK-92 CD16A and blood NK cells. Notably, the %CD107a-positive cells negatively correlated with dead Raji cells and was nearly undetectable at high NK:Raji ratios required for cytotoxicity. This bioassay is very sensitive and adaptable to assess anti-viral antibodies but unsuitable as a surrogate assay to monitor cell death after ADCC.
ARTICLE | doi:10.20944/preprints202303.0502.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: Tuberculosis; Biscoumarins; Ligand molecules; DprE1; Anti-tuberculosis activity; Molecular docking; MD Simulation; Cytotoxicity
Online: 29 March 2023 (04:21:45 CEST)
The concerning rise in emergence and prevalence of resistant strains to drugs of M. tuberculosis has ,the prompted researchers to look for new and effective treatments. With this motive, biscoumarins were identified as the lead molecules on a whole-cell-based screening of several less explored low molecular weight bioactive compounds against M. tuberculosis strains. Among the screened biscoumarins, the highest dock score derivatives were synthesized (a-h) using a programmable microwave synthesizer for better yields and reaction control. The synthesized derivatives were evaluated against H37Rv, H37Ra, M. smegmatis, an MDR surrogate model, and other bacterial strains for the structure-activity response. Assessment of the synthesized library against mycobacterial strains led to the identification of compounds (f and d) as lead anti-tuberculosis agents. Compounds (f and d) exhibited less toxicity against human cell lines. At the same time, it displayed enjoyable activity wherein MIC concentrations were observed to be 16- and 32 µg/mL against the susceptible H37Rv, and H37Ra strains of M. tuberculosis and MIC value of 128 µg/mL for M. smegmatis, respectively. For mechanistic insights and identification of drug binding targets, molecular docking and dynamic simulations were employed for a panel of 16 mycobacterial enzymes essential for mycobacterial growth and survival. These in silico studies revealed the DprE1 enzyme as a druggable target for the anti-tuberculosis activity of the selected biscoumarins derivatives. Further investigation is underway in our laboratory, leading to its development as an anti-tuberculosis drug (animal model studies).
ARTICLE | doi:10.20944/preprints202212.0436.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: Green synthesis, antibacterial PPT, iron oxide nanoparticles, orange peel extract, cytotoxicity, superparamagnetic behavior.
Online: 23 December 2022 (02:15:06 CET)
Magnetic nanoparticles based on iron oxides (MNPs-Fe) with magnetite or maghemite phases have been widely employed in bio-applications. Thus, they have been used as contrast agents in magnetic resonance imaging (MRI) and oncological treatments through different therapies. Besides, due to the vast health problem of multidrug-resistant bacterial infections, several studies have proposed MNPs-Fe as photothermal agents (PTAs) within antibacterial photothermal therapy (PTT). This work presents a quick and easy green synthesis (GS) to obtain MNPs-Fe using orange peel extract from orange waste from local commerce, which presents an environmentally friendly approach compared to traditional methods such as coprecipitation. The GS can be irradiated with microwaves to reduce the synthesis time drastically. We evaluated the weight yield of the GS and the physical-chemical and magnetic features of the synthesized MNPs-Fe. Besides their cytotoxicity in animal cell line ATCC RAW 264.7, their antibacterial activity against Staphylococcus Aureus (S. Aureus) and Escherichia Coli (E. Coli) was assessed. We found that the MNPs-Fe synthesized using the GS, with 50% v/v of NH4OH and 50% v/v of orange peel extract (50GS-MNPs-Fe) had an excellent weight yield, negligible cytotoxicity for concentrations of MNPs-Fe below 250 µg·mL-1 in 24 hours, and 8 days. In the MNPs-Fe surface, we identified a coating of organic molecules (~ 25 nm) such as terpenes, aldehydes, etc. MNPs-Fe inhibited S. Aureus and 2.54 log10 (CFU) of E. Coli under red LED light irradiation (630 nm, 65.5 mW·cm-2, 30 min). Likewise, they exhibited a superparamagnetic (SPM) behavior for temperatures above 60 K, with a size of 49.3±9.6 nm and saturation magnetization (Ms) of 72.83 and 44.16 emu·g-1 at 60 and 300 K, respectively. Therefore, 50GS-MNPs-Fe are excellent candidates as broad-spectrum PTAs in antibacterial PTT, magnetic hyperthermia (MH), or MRI.
ARTICLE | doi:10.20944/preprints202009.0094.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: Terminalia bentzoë; Mascarene endemic; cytotoxicity; antioxidant; cell cycle arrest; phenolics; bioassay-guided fractionation
Online: 4 September 2020 (10:28:57 CEST)
Tropical forests constitute prolific sanctuary of unique floral diversity and potential medicinal sources, however, many of them remains unexplored. Herein, seven Mascarene endemic plants leaves were extracted and evaluated for their in vitro antioxidant properties and antiproliferative effects on a panel of cancer cell lines using MTT and clonogenic cell survival assay. Flow cytometry and comet assay were used to investigate the cell cycle and DNA damaging effects, respectively. Bioassay guided-fractionation coupled with LC-Mass spectrometry (MS), gas chromatography-MS, and nuclear magnetic resonance spectroscopy analysis were used to identify the bioactive compounds. Among the seven plants tested, Terminalia bentzoë was comparatively the most potent antioxidant extract with significantly (p < 0.05) higher cytotoxic activities. T. bentzoë extract further selectively suppressed the growth of human hepatocellular carcinoma cells and significantly halted the cell cycle progression in G0/G1 phase, decreased the cells replicative potential and induced significant DNA damage. Ten phenolic compounds including punicalagin and ellagic acid were identified and likely contributed to the extract potent antioxidant and cytotoxic activities. These results established a promising basis for further in-depth investigations on the potential use of T. bentzoë as supportive therapy in cancer management.
ARTICLE | doi:10.20944/preprints202005.0098.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: breast cancer; snake venom; cytotoxin II; recombinant protein; apoptosis; cell cycle progression; cytotoxicity
Online: 6 May 2020 (15:12:05 CEST)
Breast cancer (BC) is among the leading causes of mortality from cancer in women. Many of the available anticancer drugs have various side effects. Therefore, researchers are seeking novel anticancer agents particularly from natural compounds and in this regard, snake venom is still one of the main sources of drug discovery. Previous studies showed potential anticancer effects of Cytotoxin II (CTII) from Naja naja oxiana against the different types of cancers. In this study, a pET-SUMO-CTII vector was transformed into SHuffle® T7 Express, an Escherichia coli strain, for recombinant protein expression (rCTII) and the cytotoxic effects of this protein was assessed in MCF-7 cells. The flow cytometry assay was applied to measure the apoptosis and cell cycle. Also, mRNA levels of the Bax, Bcl2, P53, caspase-3, caspase-8, caspase-9, caspase-10, matrix metalloproteinases (MMP)-3, and MMP-9 were analyzed by quantitative real-time PCR to determine the underlying cellular pathways affected by rCTII. The results of this study showed that treatment with 4 µg mL-1 of rCTII enhanced apoptosis through the intrinsic and extrinsic pathways. Also, the increase of the cells' proportion in the sub-G1 phase as well as a reduction in S phase was observed. In addition, the expression of MMP-3 and MMP-9 was decreased in the treated group in comparison to the control group that may contribute to the reduced migratory ability of tumor cells. These experimental results indicate that rCTII has anti-proliferative potential, and so this protein could be a potential drug for BC therapy in combination with other drugs.
ARTICLE | doi:10.20944/preprints201805.0085.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: 7-acetamido-2-aryl-5-bromoindoles; trifluoroacetylation; cytotoxicity; apoptosis; tubulin polymerization; molecular docking
Online: 4 May 2018 (07:47:06 CEST)
Structurally related 7-acetyl-2-aryl-5-bromoindoles 2a–d and the 7-acetamido-2-aryl-5-bromoindoles 4a–d as well as their corresponding 3-trifluoroacetyl–substituted derivatives 5a–d and 5e–h were evaluated for potential antigrowth effect in vitro against the human lung cancer (A549) and cervical cancer (HeLa) cells. All of the 3-trifluoroacetyl–substituted 7-acetamido-2-aryl-5-bromoindoles 5e–h were found to be more active against both cell lines when compared to the chemotherapeutic drug, Melphalan. The most active compound 5g induced apoptosis in a caspase dependent manner for both cell lines. Compounds 5e–h were found to significantly inhibit tubulin polymerization. Molecular docking of 5g into the colchicine-binding site suggests that the compounds bind to tubulin by different type of interactions including pi-alkyl, amide-pi stacked and alkyl interactions as well as hydrogen bonding with the protein residues to elicit anticancer activity.
ARTICLE | doi:10.20944/preprints201608.0111.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Erigeron floribundus; essential oil; antimicrobial; NadD; Trypanosoma brucei; cytotoxicity; antioxidant; limonene; caryophyllene oxide
Online: 10 August 2016 (12:36:57 CEST)
Erigeron floribundus (Asteraceae) is an herbaceous plant widely used in the Cameroonian traditional medicine to treat various diseases of microbial and non-microbial origin. In the present study we evaluated the in vitro biological activities displayed by the essential oil obtained from the aerial parts of E. floribundus, namely the antioxidant, antimicrobial and antiproliferative activities. Moreover, we investigated the inhibitory effects of E. floribundus essential oil on nicotinate mononucleotide adenylyltransferase (NadD), a promising new target for developing novel antibiotics, and Trypanosoma brucei, the protozoan parasite responsible for Human African trypanosomiasis. The essential oil composition was dominated by spathulenol (12.2%), caryophyllene oxide (12.4%) and limonene (8.8%). The E. floribundus oil showed a good activity against Staphylococcus aureus (IZD of 14 mm, MIC of 512 µg/mL). Interestingly, it inhibited the NadD enzyme from S. aureus (IC50 of 98 µg/mL), with no effects on mammalian orthologue enzymes. In addition, T. brucei proliferation was inhibited with IC50 values of 33.5 µg/mL with the essential oil and 5.6 µg/mL with the active component limonene. The essential oil exhibited strong cytotoxicity on HCT 116 colon carcinoma cells with an IC50 value of 14.89 µg/mL, and remarkable ferric reducing antioxidant power (TEAC= 411.9 μmol TE/g).
COMMUNICATION | doi:10.20944/preprints202311.1583.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Protein-ligand interaction; Curcumin; Jacalin; Lectin; Fluorescence; Cytotoxicity; Breast cancer cells; MDA-MB-231
Online: 26 November 2023 (06:30:33 CET)
Protein-drug interactions are crucial for understanding drug delivery and cell functions. Jacalin is a suitable molecule for such targeting, as it specifically recognizes the tu-mor-associated Thomsen-Friedenreich antigen that is expressed on the glycosylated proteins in cancer cells. The present paper describes the interaction of curcumin and jacalin, a possible carrier molecule for the delivery of antitumor drugs due to its ability to recognize tumor cells. Our results have shown that both steady state fluorescence and fluorescent label-ling of jacalin are two reliable methods to determine jacalin-curcumin interactions. The affinity of jacalin for curcumin is consistently within the micromolar range (using flu-orescence and microscale thermophoresis) showing high-affinity binding of the com-plex. In vitro experiments on the triple negative breast cancer MDA-MB-231 cells indi-cated inhibition of cell growth after treating with the jacalin-curcumin complex for 48 h. The cell survival fraction was significantly reduced to 50% after combined treatment. In this paper, we report for the first time about the jacalin-curcumin interaction. We quantified this unique biomolecular interaction and gathered additional information on the binding event. We observed that the jacalin-curcumin complex inhibits the proliferation of the triple negative breast cancer MDA-MB-231 cells.
ARTICLE | doi:10.20944/preprints202307.0169.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: HER2; breast cancer; monoclonal antibody; antitumor activities; mouse xenograft model; antibody-dependent cellular cytotoxicity
Online: 4 July 2023 (09:38:15 CEST)
Two monoclonal antibodies (mAbs) against human epidermal growth factor receptor 2 (HER2), trastuzumab and pertuzumab, were clinically approved. We previously developed a highly sensitive and specific anti-HER2 mAb, H2Mab-139 (mouse IgG1, kappa). In this study, we produced a defucosylated IgG2a version of anti‑HER2 mAb (H2Mab-139-mG2a-f) to enhance ADCC-mediated antitumor activity. H2Mab-139-mG2a-f exhibits a high binding affinity in flow cytometry with the dissociation constant (KD) determined to be 3.9 × 10‑9 M and 7.7 × 10‑9 M against HER2‑overexpressed Chinese hamster ovary (CHO)-K1 (CHO/HER2) and HER2-positive BT-474 cells, respectively. Moreover, we showed that H2Mab-139-mG2a-f exerted ADCC and complement-dependent cytotoxicity against CHO/HER2 and BT-474 cells in vitro and exhibited potent antitumor activities in the xenograft models. These results indicated that H2Mab-139-mG2a-f exerts antitumor effects against HER2-positive human breast cancers and could be useful for an antibody treatment regimen for HER2-positive human cancers.
ARTICLE | doi:10.20944/preprints202306.0167.v1
Subject: Chemistry And Materials Science, Applied Chemistry Keywords: 1,2-Diphenyl-o-carborane; Chromium Metal Complexes; Boron Neutron Capture Therapy; Biological Evaluation; Cytotoxicity
Online: 2 June 2023 (09:18:49 CEST)
The objective of this study is to design and synthesize substituted η6-chromium tricarbonyl metal complexes carrying o-carborane units as potential boron neutron capture therapy (BNCT) agents. In this study, 1,2-Diphenyl-o-carborane units were used as starting materials to generate biologically active species. We investigated how the structural changes of 1,2-diphenyl-o-carborane substituted with chromium(0) tricarbonyl affect the biological properties; [(CO)3Cr]Ph2C2 (2) and [(CO)3Cr]2Ph2C2 (3) species were produced in moderate yields. The molecular structures of compounds 1–3 were identified and established by infrared (IR), 1H, 11B, and 13C nuclear magnetic resonance (NMR), and X-ray crystallography analyses. Crystal structures of o-carboranyl chromium complexes 1 [a = 10.859(1) Å, b = 24.953(3) Å, c = 13.938(2) Å, β = 111.854(2)º], 2 [a = 10.621(3) Å, b = 17.056(5) Å, c = 12.174(4) Å, β = 106.622(5)º], and 3 [a = 17.540(2) Å, b = 18.060(2) Å, c = 19.484(4) Å, α = 105.746(2)º, β = 110.226(2)º, γ = 91.256(2)º] were obtained. In vitro study using B16 and CT26 cancer cells containing the triphenyl-o-carboranyl chromium (0) complexes Ph3C2BCr2 and Ph3C2BCr3, which we have previously reported, the compounds 2 and 3 accumulated at higher levels than compounds Ph3C2BCr2 and Ph3C2BCr3. However, the phenylated o-carboranyl chromium(0) complexes have been found to be more cytotoxic than p-boronophenylalanine (BPA).
ARTICLE | doi:10.20944/preprints202109.0527.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: Gold Nanoparticles; Hyaluronate-Thiol; In vitro; In vivo; Peritumoral; Cancer; Cytotoxicity; ICP-OES; Biodistribution
Online: 1 October 2021 (11:12:31 CEST)
Biofouling is the unwanted adsorption of cells, proteins, or intracellular and extracellular bio-molecules that can spontaneously occur on the surface of metal nanocomplexes. It represents a major issue in bioinorganic chemistry because it leads to the creation of a protein corona, which can destabilize a colloidal solution and result in undesired macrophage-driven clearance, consequently causing failed delivery of a targeted drug-cargo. Hyaluronic acid (HA) is a bioactive, natural mucopolysaccharide with excellent antifouling properties, arising from its hydrophilic and polyanionic characteristics in physiological environments which prevent opsonization. In this study, hyaluronate-thiol (HA-SH) (MW 10 kDa) was used to surface-passivate gold nanoparticles (GNPs) synthesized using a citrate reduction method. HA functionalized GNP complexes (HA-GNPs) were characterized using absorption spectroscopy, scanning electron microscopy, zeta potential, and dynamic light scattering. GNP cellular uptake and potential dose-dependent cytotoxic effects due to treatment were evaluated in vitro in HeLa cells using ICP-OES and Trypan blue and MTT assays. Further, we quantified the in vivo biodistribution of intratumorally injected HA functionalized GNPs in Lewis Lung carcinoma (LLC) solid tumors grown on the flank of C57BL/6 mice and compared localization and retention with nascent particles. Our results reveal that HA-GNPs show overall greater peritumoral distribution (**p<0.005, 3 days post-intratumoral injection) than citrate-GNPs with reduced biodistribution in off-target organs. This property represents an advantageous step forward in localized delivery of metal nano-complexes to the infiltrative region of a tumor, which may improve the application of nanomedicine in the diagnosis and treatment of cancer.
ARTICLE | doi:10.20944/preprints202008.0667.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: Ovarian cancer; drug resistance; apoptosis; proteomics; combination; cytotoxicity; artemisinin; oleanolic acid; platinum drugs; cisplatin
Online: 30 August 2020 (12:06:32 CEST)
Background: In the present study, cisplatin, artemisinin and oleanolic acid were evaluated alone and in combination, on human ovarian A2780, A2780ZD0473R and A2780cisR cancer cell lines with aim of overcoming cisplatin resistance and side effects. Methods: Cytotoxicity was assessed by MTT reduction assay. CI values were used as a measure of combined drug effect. MALDI TOF/TOF MS/MS and 2-DE gel electrophoresis were used to identify protein biomarkers in ovarian cancer and to evaluate combination effects. Results: Synergism from combinations was dependent on concentration and sequence of administration. Generally, bolus was most synergistic. 49 proteins differently expressed by 2 ≥ fold were: CYPA, EIF5A1, Op18, p18, LDHB, P4HB, HSP7C, GRP94, ERp57, mortalin, IMMT, CLIC1, NM23, PSA3,1433Z, and HSP90B were down-regulated, whereas hnRNPA1, hnRNPA2/B1, EF2, GOT1, EF1A1, VIME, BIP, ATP5H, APG2, VINC, KPYM, RAN, PSA7, TPI, PGK1, ACTG and VDAC1 were up-regulated, while TCPA, TCPH, TCPB, PRDX6, EF1G, ATPA, ENOA, PRDX1, MCM7, GBLP, PSAT, Hop, EFTU, PGAM1, SERA and CAH2 were not-expressed in A2780cisR cells. The proteins were found to play critical roles in cell cycle regulation, metabolism and biosynthetic processes and drug resistance and detoxification. Conclusion: Results indicate that appropriately sequenced combinations of cisplatin with ART and OA may provide a means to reduce side effects and circumvent platinum resistance.
REVIEW | doi:10.20944/preprints201807.0004.v1
Subject: Biology And Life Sciences, Virology Keywords: influenza; neutralising antibodies; vestigial esterase; antibody dependent cell-mediated cytotoxicity; pH-induced conformational changes
Online: 2 July 2018 (08:33:45 CEST)
Initial attempts to develop monoclonal antibodies as therapeutics to resolve influenza infections focused mainly on searching for antibodies with the potential to neutralise the virus in vitro with classical haemagglutination inhibition and micro-neutralisation assays. This led to the identification of many antibodies that bind to the head domain of haemagglutinin (HA) which generally have potent neutralisation capabilities that block viral entry or viral membrane fusion. However, this class of antibodies has a narrow breadth of protection in that they are usually strain specific. This led to the emphasis on stalk targeting antibodies which are able to bind a broad range of viral targets that span across different influenza subtypes. Recently, a third class of antibodies targeting the vestigial esterase (VE) domain have been characterised. In this review, we describe the key features of neutralising VE targeting antibodies and compare them with head and stalk class antibodies.
ARTICLE | doi:10.20944/preprints201711.0091.v2
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: asymmetrical mono-carbonyl analogs of curcumin (AMACs); synthesis; cytotoxicity, Vero; HeLa; MCF7; cell lines
Online: 4 June 2018 (08:19:03 CEST)
A series of novel asymmetrical mono-carbonyl analogs of curcumin (AMACs) were synthesized and evaluated for cytotoxic activity using the brine shrimp lethality test (BSLT) and the methyl thiazolyl tetrazolium assay against Vero, HeLa, and MCF7 cell lines. The structures of the synthesized compounds were confirmed by Fourier transform infrared spectrophotometry (FTIR), 1H-nuclear magnetic resonance (NMR), 13C-NMR, and mass spectral data. The results of the cytotoxicity evaluation showed that the synthesized compounds exhibited moderate to very high toxic activity in BSLT, requiring a concentration of 13.06–714.49 µg/mL to kill half the population. Most of the compound exhibited cytotoxic activity against HeLa cell lines, comparable to the activity of cisplatin with a concentration of the synthesized compounds required to inhibit 50% of the growth of the cell lines (IC50) value of 40.65–95.55 µM, and most of the compounds tested against MCF7 cell lines exhibited moderate to very high cytotoxic activity (IC50 value 7.86–35.88 µM). However, the selectivity index of the compounds was low, less than 1–1.96. Among the synthesized compounds, compound 1b showed the highest cytotoxicity and selectivity against MCF7 cell lines. Compound 1b could be considered for further development to obtain more active and selective chemotherapeutic agents against breast cancer.
ARTICLE | doi:10.20944/preprints202310.2000.v1
Subject: Engineering, Industrial And Manufacturing Engineering Keywords: Nanofiber (NF); cytotoxicity; polyurethane (PU); polyvinylidene fluoride (PVDF); DMSO stocks; nitric oxide production; protein expression
Online: 31 October 2023 (07:17:49 CET)
Nanofiber (NF) products exhibit outstanding performances in the materials science, textile, and medical fields, which cannot be realized using conventional technologies. However, the safety of such products is debated because of the potential risk of nanomaterials and lack of standardized guidelines for safely evaluating NF products. The global safety evaluations of nanomaterials focused on evaluating the cytotoxicity of zero-dimensional materials including nanoparticles and nanotubes based on OECD criteria. The NFs are one-dimensional materials with nanometer diameters and considerable lengths. Many fibers are applied in a densely woven web-like form, and therefore, assessing cellular penetration and fiber toxicity using the same methods is inappropriate. This study verifies the safety of polyurethane (PU) and polyvinylidene fluoride (PVDF) polymers, which are currently applied in filters and masks. To this end, polymer NFs were collected from each product, and the NFs were compared with reference samples considering their physical properties using FT-IR and Raman spectroscopy. For the safety evaluation, DMSO stocks of varying concentrations of PVDF and PU NFs (at 0.5, 1, 5, and 10 μg/mL) were prepared, and the cytotoxicity and inhibitory effects on nitric oxide production and protein expression obtained via Western blot were identified.
ARTICLE | doi:10.20944/preprints202308.1756.v2
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: PDPN; lung cancer; glioblastoma; monoclonal antibody; antitumor activities; mouse xenograft model; antibody-dependent cellular cytotoxicity
Online: 20 October 2023 (12:26:35 CEST)
We previously developed a highly sensitive and specific anti-PDPN mAb, LpMab-23 (mouse IgG1, kappa). In this study, we produced a humanized IgG1 version (humLpMab-23) and its defucosylated form (humLpMab-23-f) of an anti‑PDPN mAb to potentiate the ADCC activity. The humLpMab-23 could recognize PDPN‑overexpressed Chinese hamster ovary (CHO)-K1 (CHO/PDPN) and PDPN-positive PC-10 and LN319 cells by flow cytometry. Furthermore, we found that humLpMab-23-f exerted ADCC and complement-dependent cytotoxicity against CHO/PDPN, PC-10 and LN319 cells in vitro and exhibited potent antitumor activities in the xenograft models. These results indicated that humLpMab-23-f could be useful for an antibody treatment regimen for PDPN-positive human cancers.
ARTICLE | doi:10.20944/preprints202308.1349.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: α-Synuclein preformed fibrils (PFF); cytotoxicity; Reactive Oxygen Species (ROS); oxidative stress; and protein aggregation
Online: 18 August 2023 (10:55:57 CEST)
Oxidative stress-mediated damage is often a downstream result of Parkinson’s disease (PD), which is marked by sharp decline in dopaminergic neurons within the nigrostriatal regions of the brain, accounting for the symptomatic motor deficits in patients. Regulating the level of oxidative stress may present a beneficial approach in preventing PD pathology. Here, we assessed the efficacy of a nicotinamide adenine phosphate (NADPH) oxidase (NOX) inhibitor, an exogenous reactive oxygen species (ROS) regulator synthesized by Aptabio therapeutics with the specificity to NOX-1, 2, and 4. Utilizing N27 rat dopaminergic cells and C57Bl/6 mice, we confirmed that the exposures of alpha-synuclein preformed fibrils (PFF) induced protein aggregation, a hallmark in PD pathology. In vitro assessment of the novel compound revealed an increase in cell viability and decreases in cytotoxicity, ROS, and protein aggregation (Thioflavin-T stain) against PFF exposure at the optimal concentration of 10nM. Concomitantly, the oral treatment alleviated motor deficits in behavioral tests, such as hindlimb clasping, rotarod, pole, nesting, and grooming test, via reducing protein aggregation, based on rescued dopaminergic neuronal loss. The suppression of NOX-1, 2, and 4 within the striatum and ventral midbrain regions including SNc contributed to neuroprotective/recovery effects, making it a potential therapeutic option for PD.
ARTICLE | doi:10.20944/preprints202305.1364.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Ceratonia siliqua L.; Morocco; HPLC-DAD; Phenolics; Antioxidant activity; Antimicrobial activitiy; cytotoxicity; breast cancer; genotoxicity
Online: 19 May 2023 (03:23:35 CEST)
The botanical species Ceratonia siliqua L., commonly referred to as the Carob tree, and locally as “L’Kharrûb”, holds significance as an agro-sylvo-pastoral species, and is traditionally utilized in Morocco for treating a variety of ailments. This current investigation aims to ascertain the antioxidant, antimicrobial, and cytotoxic properties of the ethanolic extract of C. siliqua leaves (CSEE). Initially, we analyzed the chemical composition of CSEE through high-performance liquid chromatography with Diode-Array Detection (HPLC-DAD). Subsequently, we conducted various assessments, including DPPH scavenging capacity, β-carotene bleaching assay, ABTS scavenging, and total antioxidant capacity assays, to evaluate the antioxidant activity of the extract. In this study, we investigated the antimicrobial properties of CSEE against five bacterial strains (two gram-positive, Staphylococcus aureus, and Enterococcus faecalis; and three gram-negative bacteria, Escherichia coli, Escherichia vekanda, and Pseudomonas aeruginosa) and two fungi (Candida albicans, and Geotrichum candidum). Additionally, we evaluated the cytotoxicity of CSEE on three human breast cancer cell lines (MCF-7, MDA-MB-231, and MDA-MB-436) and assessed the potential genotoxicity of the extract using the comet assay. Through HPLC-DAD analysis, we determined that phenolic acids and flavonoids were the primary constituents of the CSEE extract. The results of the DPPH test indicated a potent scavenging capacity of the extract with an IC50 of 302.78 ± 7.55 µg/mL, which was comparable to that of ascorbic acid with an IC50 of 260.24 ± 6.45 µg/mL. Similarly, the β-carotene test demonstrated an IC50 of 352.06 ± 12.16 µg/mL, signifying the extract's potential to inhibit oxidative damage. The ABTS assay revealed IC50 values of 48.13 ± 3.66 TE µmol/mL, indicating a strong ability of CSEE to scavenge ABTS radicals, and the TAC assay demonstrated an IC50 value of 165 ± 7.66 µg AAE/mg. The results suggest that the CSEE extract had potent antioxidant activity. Regarding its antimicrobial activity, the CSEE extract was effective against all five tested bacterial strains, indicating its broad-spectrum antibacterial properties. However, it only showed moderate activity against the two tested fungal strains, suggesting it may not be as effective against fungi. The CSEE exhibited a noteworthy dose-dependent inhibitory activity against all the tested tumor cell lines in vitro. The extract did not induce DNA damage at the concentrations of 6.25, 12.5, 25, and 50 µg/ml, as assessed by the comet assay. However, the 100 µg/ml concentration of CSEE resulted in a significant genotoxic effect compared to the negative control. A computational analysis was conducted to determine the physicochemical and pharmacokinetic characteristics of the constituent molecules present in the extract. The Prediction of Activity Spectra of Substances (PASS) test was employed to forecast the potential biological activities of these molecules. Additionally, the toxicity of the molecules was evaluated using the Protox II webserver.
ARTICLE | doi:10.20944/preprints202001.0347.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Pachycereus weberi; Escontria chiotilla; bioactive entities; antioxidant activity; phenolic compounds; betalains; food composition; food analysis; cytotoxicity
Online: 29 January 2020 (04:29:42 CET)
Mexico has a great diversity of cacti, however, many of their fruits have not been studied in greater depth. Several bioactive compounds available in cacti juices extract have demonstrated nutraceutical properties. Two cactus species are interesting for their biologically active pigments, which are chico (Pachycereus weberi (J. M.Coult.) Backeb)) and jiotilla (Escontria chiotilla (Weber) Rose)). Hence, the goal of this work was to evaluate the bioactive entities, i.e., betalains, total phenolic, vitamin C, antioxidant activity, and mineral content in the extract of the above-mentioned P. weberi and E. chiotilla. Then, clarified extracts were evaluated for their antioxidant activity and cytotoxicity (cancer cell lines) potentialities. Based on the obtained results, Chico fruit extract was found to be a good source of vitamin C (27.19±1.95 mg L-Ascorbic acid/100g fresh sample). Moreover, chico extract resulted in a high concentration of micronutrients, i.e., potassium (517.75±16.78 mg/100 g) and zinc (2.46±0.65 mg/100 g). On the other hand, Jiotilla has a high content of biologically active pigment, i.e., betaxanthins (4.17±0.35 mg/g dry sample). The antioxidant activities of clarified extracts of chico and jiotilla were 80.01±5.10 and 280.88±7.62 (DPPH method), respectively. From the cytotoxicity perspective against cancer cell lines, i.e., CaCo-2, MCF-7, HepG2, and PC-3, the clarified extracts of chico showed cytotoxicity in CaCo-2 (49.7±0.01) and MCF-7 (45.56±0.05). Normal fibroblast cell line (NIH/3T3) was used as a control for comparison purposes. While, jiotilla extract had cytotoxicity against HepG2 (47.31±0.03) and PC-3 (53.65±0.04). These results demonstrated that Chico and jiotilla are good resources of biologically active constituents with nutraceuticals potentialities.
REVIEW | doi:10.20944/preprints202212.0048.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: poly(hexamethylene biguanide); polyhexamethylene biguanide; polyhexanide; PHMB; membrane; controlled drug release; wound dressing; antimicrobial; cytotoxicity; wound healing
Online: 2 December 2022 (10:31:38 CET)
The prevalence for chronic, non-healing skin wounds in the general population, most notably diabetic foot ulcers, venous leg ulcers and pressure ulcers, is approximately 2% and is expected to increase, driven mostly by an aging population and the steady rise in obesity and diabetes. Non-healing wounds often become infected, increasing the risk of life-threatening complications, which poses a significant socioeconomic burden. Aiming at an improved management of infected wounds, a variety of wound dressings incorporating antimicrobials (AMDs), namely polyhexanide (poly(hexamethylene biguanide); PHMB), have been introduced in the wound care market. However, many wound care professionals agree that none shows comprehensive and optimal antimicrobial activity. This manuscript summarizes and discusses studies on novel PHMB-releasing membranes (PRMs) for wound dressings, detailing their preparation, physical properties relevant in the context of AMDs, drug loading and release, antibacterial activity, biocompatibility, wound healing capacity, and clinical trials conducted. Some of these PRMs were able to improve wound healing in in vivo models, with no associated cytotoxicity, but significant differences in study design make it difficult to compare overall effi-cacies. It is hoped that this review, which includes, whenever available, international standards for testing AMDs, will provide a framework for future studies.their preparation, physical properties relevant in the context of AMDs, drug loading and release, antibacterial activity, biocompatibility, wound healing capacity, and clinical trials conducted. Some of these PRMs were able to improve wound healing in in vivo models, with no associated cytotoxicity, but significant differences in study design make it difficult to compare overall efficacies. It is hoped that this review, which includes, whenever available, international standards for testing AMDs, will provide a framework for future studies.
ARTICLE | doi:10.20944/preprints202105.0039.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: antifungal activity; Candida albicans; antibiofilm effect; mode of action; cytotoxicity; hemolytic assay; HOMO-LUMO; molecular electrostatic potential
Online: 5 May 2021 (12:04:01 CEST)
There is a need to search for new antifungals, especially for the treatment of the invasive Candida infections, caused mainly by C. albicans. These infections are steadily increasing at an alarming rate, mostly among immunocompromised patients. The newly synthesized compounds (3a-3k) were characterized by physico-chemical parameters and investigated for antimicrobial activity using the microdilution broth method to estimate minimal inhibitory concentration (MIC). Additionally, their antibiofilm activity and mode of action together with the effect on the membrane permeability in C. albicans were investigated. Biofilm biomass and its metabolic activity were quantitatively measured using crystal violet (CV) staining and tetrazolium salt (XTT) reduction assay. The cytotoxic effect on normal human lung fibroblasts and hemolytic effect were also evaluated. The results showed differential activity of the compounds against yeasts (MIC = 0.24-500 µg/mL) and bacteria (MIC = 125-1000 µg/mL). Most compounds possessed strong antifungal activity (MIC = 0.24-7.81 µg/mL). The compounds 3b, 3c, and 3e, showed no inhibitory (at 1/2 MIC) and eradication (at 8 x MIC) effect on C. albicans biofilm. Only slight decrease in the biofilm metabolic activity was observed for compound 3b. Moreover, the studied compounds increased the permeability of the membrane/cell wall of C. albicans and their mode of action may be related to action within the fungal cell wall structure and/or within the cell membrane. It is worth noting that the compounds had no cytotoxicity effect on pulmonary fibroblasts and erythrocytes at concentrations showing anticandidal activity. The present studies in vitro confirm that these derivatives appear to be a very promising group of antifungals for further preclinical studies.
ARTICLE | doi:10.20944/preprints202103.0258.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Antivirals; peptoids; LL-37; air-liquid interface; cytotoxicity; membrane disruption; COVID-19; HSV-1; SARS-CoV-2
Online: 9 March 2021 (10:25:03 CET)
Viral infections, such as those caused by Herpes Simplex Virus-1 (HSV-1) and SARS-CoV-2, affect millions of people each year. However, there are few antiviral drugs that can effectively treat these infections. The standard approach in the development of antiviral drugs involves the identification of a unique viral target, followed by the design of an agent that addresses that target. Antimicrobial peptides (AMPs) represent a novel source of potential antiviral drugs. AMPs have been shown to inactivate numerous different enveloped viruses through the disruption of their viral envelopes. However, the clinical development of AMPs as antimicrobial therapeutics has been hampered by a number of factors, especially their structure as peptides. We have examined the antiviral potential of peptoid mimics of AMPs (sequence-specific N-substituted glycine oligomers). These peptoids have the distinct advantage of being insensitive to proteases, and also exhibit increased bioavailability and stability. Our results demonstrate that several peptoids exhibit potent in vitro antiviral activity against both HSV-1 and SARS-CoV-2 when incubated prior to infection. Visualization by cryo-EM shows viral envelope disruption similar to what has been observed with AMP activity against other viruses. This suggests a common or biomimetic mechanism, possibly due to the differences between the phospholipid head group makeup of viral envelopes and host cell membranes. Furthermore, we observed no cytotoxicity against primary cultures of oral epithelial cells, thus underscoring the potential of this class of molecules as safe and effective broad-spectrum antiviral agents.
ARTICLE | doi:10.20944/preprints201807.0123.v1
Subject: Biology And Life Sciences, Virology Keywords: Snake venomics; Viperidae; Protobothrops flavoviridis; Habu pit viper; Bottom-Up; Top-Down; BPP; Tripeptide metalloprotease inhibitor; Cytotoxicity
Online: 6 July 2018 (16:34:48 CEST)
The Asian world is home to a multitude of venomous and dangerous snakes, which are attributed to various medical effects used in the preparation of traditional snake tinctures and alcoholics, like the Japanese snake wine, named Habushu. The aim of this work was to perform the first quantitative proteomic analysis of the Protobothrops flavoviridis pit viper venom. Accordingly, the venom was analyzed by complimentary bottom-up and top-down mass spectrometry techniques. The mass spectrometry-based snake venomics approach revealed that more than half of the venom is composed of different phospholipases A2 (PLA2). The combination with an intact mass profiling led to the identification of the three main Habu PLA2s. Furthermore, nearly one-third of the total venom consists of snake venom metalloproteinases and disintegrins, and several minor represented toxins families were detected: CTL, CRISP, svSP, LAAO, PDE and 5’-nucleotidase. Finally, the venom of P. flavoviridis contains certain bradykinin-potentiating peptides and related peptides, like the svMP inhibitors pEKW, pEQW, pEEW and pENW. In preliminary MTT cytotoxicity assays the highest cancerous-cytotoxicity of the crude venom was measured against human neuroblastoma SH-SY5Y cells and shows in some fractions disintegrin-like effects.
ARTICLE | doi:10.20944/preprints201807.0079.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: PLA fibers, organosulfur compounds, garlic extracts, mesenchymal stem cells, microstructure, thermal and mechanical properties, cytotoxicity, antibacterial properties.
Online: 4 July 2018 (16:19:17 CEST)
The design of biomaterial platforms able to release bioactive molecules is mandatory in tissue repair and regenerative medicine. In this context, electrospinning is a user-friendly, versatile and low-cost technique, able to process different kinds of materials in micro- and nano-fibers with a large surface area-to-volume ratio for an optimal release of gaseous signalling molecules. Recently, the antioxidant and anti-inflammatory properties of the endogenous gasotramsmitter hydrogen sulfide (H2S), as well as its ability to stimulate relevant biochemical processes on the growth of mesenchymal stem cells (MSC), have been investigated. Therefore, in this work, new poly(lactic) acid fibrous membranes (PFM), doped and functionalized with H2S slow-releasing donors extracted from garlic, were synthetized. These innovative H2S-releasing mats were characterized for their morphological, thermal, mechanical and biological properties. Their antimicrobial activity and effects on the in vitro human cardiac MSC growth, either in the presence or in the absence of oxidative stress, were here assessed. On the basis of the results here presented, these new H2S-releasing PFM could represent promising and low-cost scaffolds or patches for biomedical applications in tissue repair.
ARTICLE | doi:10.20944/preprints201805.0204.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: fluorescent magnetic submicronic polymer nanoparticles; human breast cancer; MCF-7 cell line; anticancer; cytotoxicity; in vitro cell culture
Online: 15 May 2018 (06:25:09 CEST)
Breast cancer treatment mostly revolved around radiation therapy and surgical interventions, these treatments doesn’t provide satisfactory relief to the patients and carry unmanageable side-effects. Nanomaterials show promising results in treating cancer cells and have many advantages such as high biocompatibility, bioavailability and effective therapeutic capabilities. Interestingly, fluorescent magnetic nanoparticles have been used in many biological and diagnostic applications, but there is no report of use of fluorescent magnetic submicronic polymer nanoparticles (FMSP-nanoparticles) in the treatment of human breast cancer cells. In the present study, we have tested the effect FMSP-nanoparticles on human breast cancer cells (MCF-7). We have tested different concentrations (1.25µg/1mL, 12.5µg/mL and 50µg/1mL) of FMSP-nanoparticles in MCF-7 cells and evaluated the nanoparticles response morphometrically. Our results revealed that FMSP-nanoparticles produced a concentration dependent effect on the cancer cells, dose of 1.25µg/mL produced no significant effect on the cancer cell morphology and cell death, whereas dosages of 12.5µg/mL and 50µg/mL respectively showed significant nuclear augmentation, disintegration, chromatic condensation followed by dose dependent cell death. Our results demonstrate FMSP-nanoparticles have ability to induce cell death in MCF-7 cells and may be considered as a potential anti-cancer agent for breast cancer treatments.
ARTICLE | doi:10.20944/preprints202311.1837.v1
Subject: Chemistry And Materials Science, Medicinal Chemistry Keywords: 1,3,5-triazine; nucleophilic substitution; nitrosation reaction; azido-acetylene cycloaddition; 1,2,3-triazole; hyperbranched polymers; antibacterial activity; cytotoxicity; M-HeLa; Vero
Online: 29 November 2023 (08:10:21 CET)
A new method for the synthesis of azido-propargyloxy derivatives of 1,3,5-triazine has been developed. The antibacterial activity against E. coli bacteria of propargyloxy substituted 1,3,5-triazines - 2,4,6-trispropargyloxy-1,3,5-triazine, 2-azido-4,6-bispropargyloxy-1,3,5-triazine and 2,4-diazido-6-propargyloxy-1,3,5-triazine and their hyperbranched polymers. It has been shown that the presence of an azide group in the compound directly affects the antibacterial activity. The cytotoxicity of these compounds against the M-HeLa, FetMSC and Vero cell lines was studied. The IC50 value was determined for low molecular weight compounds. It has been shown that hyperbranched polymers without azide groups don’t exhibit pronounced cytotoxicity and can be used in biomedical applications.
ARTICLE | doi:10.20944/preprints202107.0503.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Cytotoxicity; Glioblastoma multiform; Lactate dehydrogenase (LDH); Poly D- L-lactic-co-glycolic acid (PLGA); U-87 MG glioma cell lines
Online: 21 July 2021 (16:37:21 CEST)
PHLNs (polymeric lipid hybrid nanoparticles) are core–shell nanoparticle structures made up of polymer cores and lipid shells that have properties similar to both polymeric nanoparticles and liposomes. Methotrexate (MTX) loaded PLHNPs containing tween 80, phosphatidylcholine, poly D, L-lactic-co-glycolic acid (PLGA) & glyceryl tripalmitate prepared using solvent injection & homogenization method for glioblastoma treatment option. The MTX loaded PLHNPs optimized by Box–Behnken design to minimize particle size, higher entrapment efficacy, and maximize MTX concentration in the brain at 4h. The particle size, entrapment efficacy, concentration of drug in brain at 4h, zeta potential and AUC(Brain)/AUC(Plasma) ratio were in the range of 173.51-233.37nm, 70.56-86.34%, 6.38-12.38 μg/mL, 25.78-36.31mV & 1.02-5.32. in-vitro drug release studies, cellular internalization of optimized formulation against U-87 MG shows good anticancer effects.
ARTICLE | doi:10.20944/preprints201608.0162.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: bacterial ghosts (BGs); Vibrio parahaemolyticus; chemically induced lysis; minimum inhibition concentration (MIC); sodium hydroxide (NaOH); lipopolysaccharides (LPS); endotoxic activity; macrophages; cytotoxicity; cytokine
Online: 17 August 2016 (10:26:00 CEST)
Acellular bacterial ghosts (BGs) are empty non-living bacterial cell envelopes, commonly generated by controlled expression of the cloned lysis gene E of bacteriophage PhiX174. In this study, Vibrio parahaemolyticus ghosts (VPGs) were generated by chemically induced lysis and the method is based on minimum inhibitory concentration (MIC) of sodium hydroxide (NaOH), acetic acid, boric acid, citric acid, maleic acid, hydrochloric acid and sulfuric acid. The MIC values of the respective chemicals were 3.125, 6.25, < 50.0, 25.0, 6.25, 1.56 and 0.781 mg/ml. Except boric acid, the lysis efficiency was reached more than 99.99% at 5 min after treatment of all chemicals. Among those chemicals, NaOH-induced VPGs showed completely DNA-free that was confirmed by quantitative real-time PCR. Besides, lipopolysaccharides (LPS) extracted from the NaOH-induced VPGs showed no distinctive band on SDS-PAGE gel after silver staining. On the other hand, LPS extracted from wild-type bacterial cells as well as the organic acids-induced VPGs showed triple major bands and LPS extracted from the inorganic acids-induced VPGs showed double bands. It suggests that some surface structures in LPS of the NaOH-induced VPGs may be lost, weakened or modified by the MIC of NaOH. Nevertheless, Limulus amoebocyte lysate assay revealed that there is no significant difference in endotoxic activity between the NaOH-induced VPGs and wild-type bacterial cells. Macrophages exposed to the NaOH-induced VPGs at 0.5 × 106 CFU/mL showed cell viability of 97.9%, however the MIC of NaOH did not reduce the cytotoxic effect of wild-type bacterial cells. Like Escherichia coli LPS, the NaOH-induced VPGs are an excellent activator of pro-inflammatory cytokines (IL-1β and iNOS), anti-inflammatory cytokine (IL-10) and dual activities (IL-6) in the stimulated macrophage cells. On the other hand, the induction of TNF-α mRNA was remarkable in the macrophages exposed with wild-type cells. Scanning electron microscopy showed the formation of trans-membrane lysis tunnel structures in the NaOH-induced VPGs. SDS-PAGE and agarose gel electrophoresis also confirmed that cytoplasmic proteins and genomic DNA released from the VPGs to culture medium through the lysis tunnel structures. Taken together, all these results indicated that the NaOH-induced VPGs show the potency of safe, economical and effective inactivated bacterial vaccine candidate.
ARTICLE | doi:10.20944/preprints202310.1287.v1
Subject: Chemistry And Materials Science, Chemical Engineering Keywords: lead ions (Pb+2); Zn-Fe LDH/PANI; Carbon paste electrode (CPE); differential pulse voltammetry (DPV); Zn/Mg/Fe LDH; Atomic absorption spectrophotometer (ASS); cytotoxicity
Online: 19 October 2023 (13:38:55 CEST)
The requirement for developing tools capable of detecting and monitoring heavy metals (HMs) has recently taken on more significance due to worries about their toxic effect on human health and aquatic habitats. In this study, a simple electrochemical sensing carbon paste electrode (CPE) based on composite of Zinc/Iron layered double hydroxide (LDH) and polyaniline (PANI) was developed for the determination of lead ions in aquatic solutions. For this purpose, Zn-Fe LDH/PANI was prepared and characterized by Fourier transform infrared (FTIR), X ray diffraction (XRD), and scanning electron microscopy (SEM). Modified carbon electrode based Zn-Fe LDH/PANI was electrochemically characterized compared with unmodified electrode in FCN as a redox probe using cyclic voltammetry (CV). Thus, Zn-Fe LDH/PANI was utilized as sensing material for the electrochemical determination of lead ions using differential pulse voltammetry (DPV). Zn-Fe LDH/PANI/CPE show limits of detection (LOD) and quantification (LOQ) of 167.8 nM and 559.4 nM, respectively. Zn/Mg/Fe LDH was prepared using co-precipitation method and characterized by XRD, FTIR, SEM and BET, used for removal of Pb+2 ions. Removal process was investigated at different conditions as pH, metal ion concentrations, starting adsorbent dose at first and contact time. Zn/Mg/Fe LDH was evaluated as an effective adsorbent material for lead ions elimination in aquatic solutions, with capacity of adsorption 700 mg/g. The elimination of lead ions on Zn/Mg/Fe LDH fitted the pseudo first-order kinetics model and the isotherm was matched with Langmuir model. Studies revealed that the ideal removal conditions were pH = 5.0, an adsorbent mass of 0.05 g, and 20 ml of 50 ppm metal ion concentration at 60 min. The Zn-Fe LDH/PANI composite also showed potential anti-cancer properties against lung cancer cells (A549) while maintaining safety for normal lung fibroblast cells (WI-38). Collectively, advancements in electrochemical sensors offer promising solutions for lead ion detection, with wide-reaching applications in wastewater treatment and cytotoxicity assessment. These innovations have the potential to enhance environmental monitoring and public health safety.
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: NK cell biology; NK cell subsets; NK activating receptors; cell adhesion molecules; granule polarization; cytotoxicity assay; cis interactions; trogocytosis; NK cell degranulation; NK-Based Immunotherapies
Online: 14 February 2020 (03:13:05 CET)
NK population is characterized by distinct NK cell subsets which respond differently to the various activating stimuli. For this reason, the determination of the optimal cytotoxic activation of the different NK subsets can be a crucial aspect to be exploited to counter cancer cells in oncologic patients. To evaluate how the triggering of different combination of activating receptors can affect the cytotoxic responses of different NK cell subsets, we developed a microbead-based degranulation assay. By using this new assay, we were able to detect CD107a+ degranulating NK cells even within the less cytotoxic subsets (i.e. resting CD56bright and unlicensed CD56dim NK cells), thus demonstrating its high sensitivity. Interestingly, signals delivered by the co-engagement of NKp46 with 2B4, but not with CD2 or DNAM-1, strongly cooperate to enhance degranulation on both licensed and unlicensed CD56dim NK cells. Of note, 2B4 is known to bind CD48 hematopoietic antigen, therefore this observation may provide the rationale why CD56dim subset expansion correlates with successful hematopoietic stem cell transplantation mediated by alloreactive NK cells against host T, DC and leukemic cells, while sparing host non-hematopoietic tissues and graft versus host disease. The assay further confirms that activation of LFA-1 on NK cells leads to their granule polarization, even if, in some cases, this also takes to an inhibition of NK degranulation, suggesting that LFA-1 engagement by ICAMs on target cells may differently affect NK cell response. Finally, we observed that NK cells undergo a time-dependent spontaneous (cytokine-independent) activation after blood withdrawal, an aspect that may strongly bias the evaluation of the resting NK cell response. Altogether our data may pave the way to develop new NK activation and expansion strategies that target the highly cytotoxic CD56dim NK cells and can be feasible and useful for cancer and viral infection treatment.
ARTICLE | doi:10.20944/preprints202301.0489.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: multidrug resistance; MDR; EPB (Xenorhabdus; (X. budapestensis; X. szentirmaii; X. innexii); and Photorhabdus) species); CFCM (cell-free conditioned media); NR-AMP (non-ribosomal-templated antimicrobial peptides); anti-microbial; (anti-bacterial; - anti-coccidial; -anti-protist; - activity; cytotoxicity; in vitro; in situ (local) bioavailablity; XENOFOOD; allometry
Online: 27 January 2023 (06:21:56 CET)
Whether the different NR-AMPs could ever be utilized as drugs not only against prokaryotic (bacteria) pathogens but eukaryotic (fungal pathogens, and parasitic protists) depends on the side effects. To get experimental experience about the option of applying EPB-produced antimicrobials to pathogens, and parasites of veterinary significance, we present here the results of an in vitro, and an accompanying in vivo study on chicken. In the in vitro study, we tested the cytotoxic potential of the cell-free conditioned culture media (CFCM) of three entomopathogenic bacterium species, - X. budapestensis, DSM16342 (EMA); X. szentirmaii DSM16338 (EMC); Photorhabdus luminescens ssp. akhurstii TT01 - on chicken tissue culture cells, namely, on the Leghorn Male Hepatoma (LMH),  cells, (a permanent confluent hepato-carcinoma cell line). Each CFCM proved rather cytotoxic in this test. In the in vivo study, we fed freshly hatched male broiler chickens for 42 days with XENOFOOD  which contained autoclaved cultures of EMA, and EMC). These bacteria were grown on standard chicken (starter and grower) [HM3] [u4] feed, and the whole culture was used as a “food supplement”. [HM5]. It had been known that these EPB species cannot grow that is, not viable) atbody temperature (above 33 C).