ARTICLE | doi:10.20944/preprints202010.0504.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: glycine transporter; glycine receptor; analgesics; lipids
Online: 26 October 2020 (08:46:31 CET)
Reduced inhibitory glycinergic neurotransmission is implicated in a number of neurological conditions such as neuropathic pain, schizophrenia, epilepsy and hyperekplexia. Restoring glycinergic signalling may be an effective method of treating these pathologies. Glycine transporters (GlyTs) control synaptic and extra-synaptic glycine concentrations and slowing the reuptake of glycine using specific GlyT inhibitors will increase glycine extracellular concentrations and increase glycine receptor (GlyR) activation. Glycinergic neurotransmission can also be improved through positive allosteric modulation (PAM) of GlyRs. Despite efforts to manipulate this synapse, no therapeutics currently target it. We propose that dual action modulators of both GlyTs and GlyRs may show greater therapeutic potential than those targeting individual proteins. To show this, we have characterized a co-expression system in Xenopus laevis oocytes consisting of GlyT1 or GlyT2 co-expressed with GlyRα1. We use two electrode voltage clamp recording techniques to measure the impact of GlyTs on GlyRs and the effects of modulators of these proteins. We show that increases in GlyT density in close proximity to GlyRs diminish receptor currents. Reductions in GlyR mediated currents are not observed when non-transportable GlyR agonists are applied or when Na+ is not available. GlyTs reduce glycine concentrations across different concentration ranges, corresponding with their ion-coupling stoichiometry, and full receptor currents can be restored when GlyTs are blocked with selective inhibitors. We show that partial inhibition of GlyT2 and modest GlyRα1 potentiation using a dual action compound, is as useful in restoring GlyR currents as a full and potent single target GlyT2 inhibitor or single target GlyRα1 PAM.
Fri, 9 October 2020
ARTICLE | doi:10.20944/preprints202010.0196.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: drug discovery; artificial intelligence; protein discovery; binding prediction; synthetic molecule generation; synthetic drug
Online: 9 October 2020 (11:13:19 CEST)
In this paper we propose the generation of synthetic small and more sophisticated molecule structures that optimize the binding affinity to a target (ASYNT-GAN). To achieve this we leverage on three important achievements in A.I.: Attention, Deep Learning on Graphs and Generative Adversarial Networks. Similar to text generation based on parts of text we are able to generate a molecule architecture based on an existing target. By adopting this approach, we propose a novel way of searching for existing compounds that are suitable candidates. Similar to question and answer Natural Language solutions we are able to find drugs with highest relevance to a target. We are able to identify substructures of the molecular structure that are the most suitable for binding. In addition, we are proposing a novel way of generating the molecule in 3D space in such a way that the binding is optimized. We show that we are able to generate compound structures and protein structures that are optimised for binding to a target.
Mon, 21 September 2020
ARTICLE | doi:10.20944/preprints202009.0501.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: human arsenic exposure; water source; risk factors; Thailand
Online: 21 September 2020 (11:32:03 CEST)
Three decades ago, human arsenic (As) contamination has been recognized in Ron Phibun, a sub-district with tin mining activity in southern Thailand. Since then different government bodies have attempted to mitigate the As-contamination problem by providing safe water in households. The most recent study conducted during 2000-2002 reported only a small fraction of population still had high urinary As level. Less attention has been paid to this issue afterwards. The present study aimed to re-assess the current situation, including human As contamination, water use behavior as well as identify risk factors of elevated As concentration among residents of Ron Phibun. The survey of 560 participants living in Ron Phibun with urinary As assessment was conducted. The median urinary As concentration of study participants was higher than normal. Consumption of shallow well water, a source generally considered as As-contaminated, was higher than a previous survey. A significant association was observed between urinary As concentrations and water sources for drinking and cooking. Gender and educational level were found to be associated with urinary As concentration. Significant associations between urinary As concentration and certain diseases (respiratory diseases, dermatitis, and dyslipidemia) were observed. The findings suggested further investigation of all water sources in the area for As contamination.
Tue, 15 September 2020
ARTICLE | doi:10.20944/preprints202009.0326.v1
Subject: Medicine & Pharmacology, Pharmacology & 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.
Sun, 13 September 2020
ARTICLE | doi:10.20944/preprints202009.0281.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: coil resistance; ecigarette; electronic nicotine delivery system; pod-style; atomizer
Online: 13 September 2020 (11:56:34 CEST)
In Electronic Nicotine Delivery System (ENDS), coil resistance is an important factor in the generation of heat energy used to change e-liquid into vapor. An accurate and unbiased method for testing coil resistance is vital for understanding its effect on emissions and reporting results that are comparable across different types and brands of ENDS and measured in different laboratories. This study proposes a robust, accurate and unbiased method for measuring coil resistance. An apparatus is used which mimics the geometric configuration and assembly of ENDS pods and power control units. The method is demonstrated on two commonly used ENDS devices, the ALTO by Vuse and JUUL. Analysis shows that the proposed method is stable and reliable. The two-wire configuration introduced a positive measurement bias of 0.086 [ohm], which is a significant error for sub-ohm coil designs. The four-wire configuration is far less prone to bias error. We observed a significant difference in coil resistance of 0.593 [ohm] (p<0.001) between the two products tested. The mean resistance and standard deviation of the pod coil assemblies was shown to be 1.031 (0.067) [ohm] for ALTO and 1.624 (0.033) [ohm] for JUUL. The variation in coil resistance between products and within products can have significant impacts on aerosol emissions.
Wed, 9 September 2020
ARTICLE | doi:10.20944/preprints202009.0205.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Franz-Bampa; BCS drugs; biomimetic membrane; Franz cell; passive drug transport
Online: 9 September 2020 (10:25:54 CEST)
A major parameter controlling the extent and rate of oral drug absorption is permeability through the lipid bilayer of intestinal epithelial cells. Here, a biomimetic artificial membrane permeability assay (Franz-Bampa) was validated using Franz cells apparatus. Both high and low permeability drugs (metoprolol and mannitol, respectively) were used as external standards. Biomimetic properties of Franz-Bampa were also characterized by electron paramagnetic resonance spectroscopy (EPR). Moreover, the permeation profile for the 14 BCS class I-IV drugs cited in the FDA guidance (including other drugs as acyclovir, cimetidine, diclofenac, ibuprofen, piroxicam, and trimethoprim) were measured across Franz-Bampa. Apparent permeability (Papp) was compared to literature fraction dose absorbed in humans (Fa%). Papp in Caco-2 cells and Corti artificial membrane were likewise compared to Fa% to assess Franz-Bampa performance. Mannitol and metoprolol Papp values across Franz-Bampa were lower (3.20 x 10-7 and 1.61 x 10-5 cm/s, respectively) than those obtained across non-impregnated membrane (2.27 x 10-5 and 2.55 x 10-5 cm/s, respectively), confirming lipidic barrier resistivity. Performance of the Franz cell permeation apparatus using an artificial membrane showed similar log linear correlation (R2 = 0.664) with Fa%, as seen for Papp in Caco-2 cells (R2 = 0.805). Data support the validation of the Franz-Bampa method for use during drug discovery process.
Sun, 6 September 2020
REVIEW | doi:10.20944/preprints202009.0146.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: homocysteine; small vessel disease; neuroinflammation; neurodegneration; endothelium
Online: 6 September 2020 (15:53:11 CEST)
Homocysteine (Hcy) is a sulfur-containing amino acid that is generated during methionine metabolism. Hyperhomocysteinemia (HHcy) is typically defined as levels >15 micro mols/L. Elevated plasma levels of Hcy can be caused by the deficiency of either vitamin B12 or folate. The active role of homocysteine is quite ambivalent: many studies detected its potential impact on neurological events; others try to identify it as one of the possible risk factors of cardiovascular events, but with a complementary and secondary role. HHcy has been reported in many neurologic disorders, including cognitive impairment and stroke, independent of long-recognized factors such as hyperlipidemia, hypertension, diabetes mellitus, and smoking. Nowadays, homocysteine could be considered as a possible link between a common vascular risk factor and potential alterations in degenerative neuronal disorders. HHcy-induced oxidative stress, endothelial dysfunction, inflammation, smooth muscle cell proliferation, and endoplasmic reticulum stress; all these aspects have been considered to play an essential role in the pathogenesis of several diseases, including atherosclerosis, major stroke, and vascular dementia. Specific models of astrocytes impairment in HHcy-mice, which mimic small vessel disease, have been developed with a three-step investigation (at 6, 10, 14 weeks of B6, B9, and B12 detrimental diet in wild type HHcy mouse). These studies found out that after ten weeks on a diet (at the most after 14 weeks), end-feet disruption occurs. This phenomenon is concomitant to reduced vascular labeling for aquaporin -4-water channels, lower protein/mRNA levels for Kir4.1, and BK potassium channels, associated with a higher expression of MMP-9. The most exciting finding is that microglial activation in this mice model was evident since the precocious time of observation (6-week time) and precedes astrocytic changes. Our research aims to review the possible role of HHcy in neurodegenerative disease and small-vessel disease and to understand its pathogenic impact.
Sat, 5 September 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Cannabis; Metabolite; Principal Component Analysis; Random Forest
Online: 5 September 2020 (07:51:50 CEST)
The many strains of Cannabis spp. are associated with many effects on users and contain many different potentially psychoactive metabolites, but the links between metabolite profiles and user effects are unclear. Here we take a statistical approach to linking cause (i.e. metabolites) to effects in Cannabis spp. through the prism of strains, using quantitative data for metabolite composition and user effects. We find that species (indica vs. sativa) explains <2% of the variability in metabolite profiles, while strain explains 1/3 of variability, indicating species is nonindicative of metabolite composition, while strain is approximately indicative. Using random forests we generate a table of potential metabolite-effect links. We also find that effect-weighted metabolite composition can effectively be described in terms of four values representing the concentrations of pairs or triplets of particular compounds.
Fri, 4 September 2020
ARTICLE | doi:10.20944/preprints202009.0094.v1
Subject: Medicine & Pharmacology, Pharmacology & 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.
Mon, 24 August 2020
ARTICLE | doi:10.20944/preprints202008.0506.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: rheumatoid arthritis; SNP; DMARD; methotrexate; pharmacogenomics
Online: 24 August 2020 (07:33:05 CEST)
Rheumatoid arthritis (RA); is a chronic systemic autoimmune disease which causes loss of joint function and significantly reduces quality of life. Plasma metabolite concentrations of disease-modifying anti-rheumatic drugs (DMARDs) can influence treatment efficacy and toxicity. This study explored the relationship between DMARD metabolising gene variants and plasma metabolite levels in RA patients. DMARD metabolite concentrations were determined by tandem mass-spectrometry in plasma samples from 100 RA patients with actively flaring disease, collected at two intervals. Taqman-probes were used to discriminate single nucleotide polymorphism (SNP) genotypes in cohort genomic DNA: rs246240 (ABCC1), rs1476413 (MTHFR), rs2231142 (ABCG2), rs3740065 (ABCC2), rs4149081 (SLCO1B1), rs4846051 (MTHFR), rs10280623 (ABCB1), rs16853826 (ATIC), rs17421511 (MTHFR) and rs717620 (ABCC2). Mean plasma concentrations of methotrexate (MTX) and MTX-7-OH metabolites were higher (p<0.05, C.I. 95%) at baseline in rs4149081 GA genotype patients. Patients with rs1476413 SNP TT or CT alleles in the have significantly higher (p<0.001, 95% C.I) plasma poly-glutamate metabolites at both study time points and correspondingly elevated disease activity scores. Patients with the rs17421511 SNP AA allele reported significantly lower pain scores (p<0.05, 95% C.I.) at both study intervals. Genotyping strategies could help prioritise treatments to RA patients most likely to gain clinical benefit, whilst minimizing toxicity.
REVIEW | doi:10.20944/preprints202008.0500.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Alzheimer; blood brain barrier; CD4+ T cells; migration; medication
Online: 24 August 2020 (03:08:41 CEST)
The effect of Alzheimer's disease (AD) medications on CD4+ T cells homing has not been thoroughly investigated. Alzheimer's disturbs the life of at least five million persons in the USA. CD4+ T cells could both exacerbate and reduce AD symptoms. Regulating CD4+ T cells homing to the leaky blood-brain barrier (BBB) constitutes a new hope for enhancing AD prognosis. Alzheimer's drugs such as Donepezil (Aricept), Rivastigmine (Exelon), Galantamine (Razadyne) and memantine are known to play an important part in regulating the neurotransmitters mechanisms. However, little is known about the effect of these drugs on CD4+ T cells homing. In this review, we focus on current and new drugs that could modulate CD4+ T cells interactions with the BBB in AD.
Thu, 20 August 2020
ARTICLE | doi:10.20944/preprints202006.0107.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Ang II; COVID19; erythropoietin; EPO-R; neuroinflammation: AT1R; SARS-CoV2; angiotensin(1-7); COVID-19 encephalopathy
Online: 20 August 2020 (09:06:38 CEST)
Neuroinflammation, defined as inflammatory reactions mediated by cytokines, chemokines, reactive oxygen species, and secondary messengers in the central nervous system (CNS) including the brain and spinal cord is the basis of many neurological disorders. Recently, erythropoietin (EPO) has been considered and studied as a modulator of neuroinflammation. On this article minireview of pathophysiology of neuroinflammation and the neuroprotective effects of EPO is discussed and a case of subacute huge subdural hematoma with double mydriasis operated urgently, treated with low daily dose (vs high dose once or twice a month in the literature) of EPO and recovered fully and discharged home with good consciousness is reported. In addition, the probable unfavorable outcome of erythropoietin administration in patients with neuroinflammation in COVID-19 is considered.
Tue, 18 August 2020
ARTICLE | doi:10.20944/preprints202008.0389.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: ECN; neuropathic pain; oxidative stress; apoptosis; myelin sheath; spectroscopy
Online: 18 August 2020 (12:00:15 CEST)
7β-(3-ethyl-cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (ECN), a sesquiterpenoid obtained from a natural origin (Tussilago farfara)has proved to be effective in minimizing various side effects associated with opioids and nonsteroidal anti-inflammatory drugs. The current study focused on investigating the effects of ECN on neuropathic pain induced by partial sciatic nerve ligation (PSNL) by mainly focusing on oxidative stress, inflammatory and apoptotic proteins expression in mice. Neuropathic pain was induced in mice by PSNL surgery performed on day 1 and ECN (1 and 10 mg/kg, i.p.), was administered once daily for 11 days, starting from the third day after surgery. ECN post-treatment was found to reduce hyperalgesia and allodynia in a dose dependent manner. ECN significantly reversed the severity of neuropathic pain by improving distress symptoms and survival rate. ECN remarkably reversed the histopathological abnormalities associated with oxidative stress, apoptosis and inflammation. Furthermore, ECN prevented the suppression of antioxidants (glutathione, glutathione-S-transferase, catalase, superoxide dismutase, NF-E2-related factor-2 (Nrf2), hemeoxygenase-1 and NAD(P)H: quinone oxidoreductase) by PSNL. Moreover, pro-inflammatory cytokines (tumor necrotic factor alpha, interleukin 1 beta, interleukin 6, cyclooxygenase-2 and inducible nitric oxide synthase) expression was reduced by ECN administration. Treatment with ECN was successful in reducing caspase-3 level consistent with the observed modulation of pro-apoptotic proteins. Additionally, ECN showed protective effect on the lipid content of myelin sheath as evident from FTIR spectroscopy which showed the shift of lipid component bands to higher values. Thus, anti-neuropathic potential of ECN might be due to inhibition of oxidative stress, inflammatory mediators and pro-apoptotic proteins.
Fri, 14 August 2020
BRIEF REPORT | doi:10.20944/preprints202008.0315.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Indoor; PM10; pulmonary disease; inflammation; IFN; type I interferon; cytokine; epithelial cell
Online: 14 August 2020 (09:22:59 CEST)
Indoor dusts are collectively formed from anthropogenic and atmospheric activities. Particle matter 10 (PM10) is inhalable and causes significant inflammation by interaction with the pulmonary epithelial barrier. The mediators involved in bronchial epithelial cells response to dust are remined unknown. The air-liquid interface of our lung on chip model was exposed to indoor dust collected from highly polluted houses in Delhi, India. The media were collected after 4 days and cytokine levels were measured. We found that the concentration of IFN, IFNγ, Interleukin-6 (IL-6), IL1b, TNFa, and Granulocyte monocyte colony stimulating factor (GM-CSF) were significantly increased after exposure to indoor dust. IFN type I pathways were a major response from dust exposure. Further investigation is needed to determine the mechanism of action and targets of dust in bronchial epithelial cells.
Wed, 12 August 2020
ARTICLE | doi:10.20944/preprints202008.0283.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Adverse drug reaction; COVID-19 treatment
Online: 12 August 2020 (11:12:41 CEST)
BACKGROUND: From March to April 2020, Spain was the center of the SARS-CoV-2 pandemic, particularly Madrid with approximately 30% of the cases in Spain. The aim of this study is to report the suspected serious adverse drug reactions (SADRs) in COVID-19 patients versus non-COVID-19 patients detected by the prospective pharmacovigilance program based on automatic laboratory signals (ALSs) in the hospital (PPLSH) during that period. We also compared the results with the suspected SADRs detected during the same period for 2019. METHODS: All ALSs that reflected potential SADRs (including neutropenia, pancytopenia, thrombocytopenia, anemia, eosinophilia, leukocytes in cerebrospinal fluid, hepatitis, pancreatitis, acute kidney injury, rhabdomyolysis and hyponatremia were prospectively monitored in hospitalized patients during the study periods. We analyzed the incidence and the distribution of causative drugs for the COVID-19 patients. RESULTS: The incidence rate of SADRs detected in the COVID-19 patients was 760.63 (95% CI 707.89–816.01) per 10,000 patients, 4.75-fold higher than the SADR rate for non-COVID-19 patients (160.15 per 10,000 patients,95% CI 137.09–186.80), and 5.84-fold higher than the SADR rate detected for the same period in 2019 (130.19 per 10,000 patients, 95% CI 109.53–154.36). The most frequently related drugs were tocilizumab (59.84%), dexketoprofen (13.93%), azithromycin (8.43%), lopinavir-ritonavir (7.35%), dexamethasone (7.62%), and chloroquine/hydroxychloroquine (6.91%). CONCLUSIONS: The incidence rate of SADRs detected by the PPSLH in patients with COVID-19 was 4.75-fold higher than that of the non-COVID-19 patients. Caution is recommended when using medications for COVID-19 patients, especially drugs that are hepatotoxic, myotoxic, and those that induce thromboembolic events.
REVIEW | doi:10.20944/preprints202008.0273.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Mycobacterium abscessus, drug treatment, experimental therapy, review,
Online: 12 August 2020 (08:01:41 CEST)
Mycobacterium abscessus is a non-tuberculous mycobacteria notoriously known for causing severe, chronic infections. Treatment of these infections is challenging due to either intrinsic or acquired resistance of M. abscessus to multiple antibiotics. Despite prolonged poly-antimicrobial therapy, treatment of M. abscessus infections often fails, leading to progressive morbidity and eventual mortality. Great research efforts are invested in finding new therapeutic options for M. abscessus. Clofazimine and rifabutin are known anti-mycobacterial antibiotics, repurposed for use against M. abscessus. Novel antimicrobials active against M. abscessus include delamanid, pretomanid and PIPD1 and the recently approved beta-lactamase inhibitors avibactam, relebactam and vaborbactam. Previously unused antimicrobial combinations e.g. vancomycin-clarithromycin and dual beta-lactam therapy have been shown to have synergistic effect against M. abscessus in experimental models, suggesting their possible use in multiple-drug regimens. Finally, engineered phage therapy has been reported to be clinically successful in a severe case of disseminated M. abscessus infection. While many of these experimental therapeutics have shown activity against M. abscessus in vitro, as well as intracellular and/or animal models, most have little if any evidence of effect in humans infections. Clinical studies of M. abscesssus treatments are needed in order to reliably determine the value of their incorporation in therapeutic regimens.
Tue, 11 August 2020
REVIEW | doi:10.20944/preprints202008.0260.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COPD; muco-obstructive lung diseases; airway mucus hypersecretion; MUC5AC; cell differentiation
Online: 11 August 2020 (09:20:57 CEST)
Chronic obstructive pulmonary disease (COPD) is associated with high morbidity and mortality globally. Studies show that airway mucus hypersecretion strongly compromises lung function, leading to frequent hospitalization and mortality, highlighting an urgent need for effective COPD treatments. MUC5AC is known to contribute to severe muco-obstructive lung diseases, worsening COPD pathogenesis. Various pathways are implicated in the aberrant MUC5AC production and secretion MUC5AC. These include signaling pathways associated with mucus-secreting cell differentiation [ nuclear factor-κB (NF-кB)and IL-13-STAT6- SAM pointed domain containing E26 transformation-specific transcription factor (SPDEF), as well as epithelial sodium channel (ENaC) and cystic fibrosis transmembrane conductance regulator (CFTR)], and signaling pathways related to mucus transport and excretion-ciliary beat frequency (CBF). Various inhibitors of mucus hypersecretion are in clinical use but have had limited benefits against COPD. Thus, novel therapies targeting airway mucus hypersecretion should be developed for effective management of muco-obstructive lung disease. Here, we systematically review the mechanisms and pathogenesis of airway mucus hypersecretion, with emphasis on multi-target and multi-link intervention strategies for the elucidation of novel inhibitors of airway mucus hypersecretion.
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Covid-19; proteins; normal-modes; protein-drug interactions; chloroquine; ivermectin; remdesivir; sofosbuvir; boceprevir; α-difluoromethylornithine (DMFO)
Online: 11 August 2020 (04:09:43 CEST)
We report the results of our study of approved drugs as potential treatments for COVID 19, based on the application of various bioinformatics predictive methods. The drugs studied include chloroquine, ivermectin, remdesivir, sofosbuvir, boceprevir, and α-difluoromethylornithine (DMFO). Our results indicate that these small molecules selectively bind to stable, kinetically active residues and residues adjoining them on the surface of proteins and inside protein pockets, and that some prefer hydrophobic over other active sites. Our approach is not restricted to viruses and can facilitate rational drug design, as well as improve our understanding of molecular interactions, in general.
Fri, 7 August 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; paracetamol; NSAIDs; inflammation; lung injury; oxidative damage; glutathione; antioxidant.
Online: 7 August 2020 (11:02:20 CEST)
COVID-19 pandemic represents an unprecedented sanitary threat: antiviral and host-directed medications to treat the disease are still urgently needed.A great effort has been paid to find drugs and treatments for hospitalized, severely ill patients. However, medications used for the domiciliary management of initial symptoms, notwithstanding their importance, have not been and are not presently regarded with the same attention. In analogy with other respiratory viral infections, COVID-19 patients in the early phase require specific antivirals (still lacking) and non-etiotropic drugs to lower pain, fever and control inflammation. Non-steroidal antinflammatory drugs (NSAIDs) and paracetamol (PAC) are widely used as non-etiotropic agents in these conditions and hence are both theoretically repurposable for COVID-19. However, a warning from some research reports and National Authorities raised NSAIDs safety concerns because of the supposed induction of ACE2 protein levels (the receptor used by SARS-CoV2 to enter host airways cells), the risk of bacterial superinfections and masking of disease symptoms. As a consequence, the use of NSAIDs was, and is, strongly discouraged while the alternative adoption of paracetamol is still preferred.On the basis of novel data and hypothesis on the possible role of scarce glutathione (GSH) levels in the exacerbation of COVID-19 and of the GSH depleting activity of PAC, this commentary raises the question of whether PAC may produce an oxidative imbalance which could be detrimental in COVID-19 clinical outcomes.
Tue, 4 August 2020
REVIEW | doi:10.20944/preprints202008.0100.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: adrenoceptor; constitutive activity; drug development; inverse agonism
Online: 4 August 2020 (16:01:12 CEST)
As many if not most ligands at G protein-coupled receptor antagonists are inverse agonists, we have systematically reviewed inverse agonism at the nine adrenoceptor subtypes. Except for β3-adrenoceptors, inverse agonism has been reported for each of the adrenoceptor subtypes, most often for β2-adrenoceptors, including endogenously expressed receptors in human tissues. As with other receptors, detection and degree of inverse agonism depends on the cells and tissues under investigation, i.e. is greatest when the model has a high intrinsic tone/constitutive activity for the response being studied. Accordingly, it may differ between parts of a tissue, for instance atria vs. ventricles of the heart, and within a cell type between cellular responses. The basal tone of endogenously expressed receptors often is low, leading to less consistent detection and smaller extent of observed inverse agonism. The extent inverse agonism depends on specific molecular properties of a compound but clusters by chemical class. While inverse agonism is a fascinating facet in attempts to mechanistically understand observed drug effects, we are skeptical whether an a priori definition of extent of inverse agonism in the target product profile of a developmental candidate is a meaningful option in drug discovery and development.
Sun, 2 August 2020
REVIEW | doi:10.20944/preprints202008.0017.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: μ opioid receptor; receptor model; biased ligands; dependence; pain therapy; neonatal opioid withdrawal syndrome; naltrexone; 6β-naltrexol; buprenorphine
Online: 2 August 2020 (11:27:40 CEST)
Opioid analgesics are effective pain therapeutics but cause various adverse effects and addiction. For safer pain therapy, biased opioid agonists selectively target distinct m opioid receptor (MOR) conformations, while the potential of biased opioid antagonists has been neglected. Agonists convert a dormant receptor form (MOR-m) to a ligand-free active form (MOR-m*), which mediates MOR signaling. Moreover, MOR-m converts spontaneously to MOR-m* (basal signaling). Persistent upregulation of MOR-m* has been invoked as a hallmark of opioid dependence. Contrasting interactions with both MOR-m and MOR-m* can account for distinct pharmacological characteristics of inverse agonists (naltrexone), neutral antagonists (6b-naltrexol), and mixed opioid agonist-antagonists (buprenorphine). Upon binding to MOR-m*, naltrexone but not 6b-naltrexol suppresses MOR-m*signaling. Naltrexone blocks opioid analgesia non-competitively at MOR-m*with high potency, whereas 6BN must compete with agonists at MOR-m, accounting for ~100-fold lower in vivo potency. Buprenorphine’s bell-shaped dose-response curve may also result from opposing effects on MOR-m and MOR-m*. In contrast, we find that 6b-naltrexol potently prevents dependence, below doses affecting analgesia or causing withdrawal, possibly binding to MOR conformations relevant to opioid dependence. We propose that 6b-naltrexol is a biased opioid antagonist modulating opioid dependence at low doses, opening novel avenues for opioid pain therapy and use management.
Thu, 23 July 2020
BRIEF REPORT | doi:10.20944/preprints202007.0541.v1
Online: 23 July 2020 (08:24:54 CEST)
Multicompartment compliance aids (MCAs) are devices with each discrete section denoting a single dosing occasion. The purpose of an MCA is to maximize patient adherence and thereby optimize the treatment benefits. These devices are widely employed throughout western Europe and UK and use appears to be rapidly increasing (2) although the RPS as moved away from these devices as a means to improve adherence. We analysed MCAs from various pharmacies over a wide geographic area in England and North Wales. We concluded that most MCA users are elderly patients. Also, most of the patients suffer of combined cardiovascular disease. However, a significant proportion of patients falls in the mental/ neurological disease category. Additionally, most of the externals added to MCAs are inhalers and painkillers. Moreover, SDIs are more frequent in female patients and these SDI are mainly related with mental health medication, cardiovascular disease medication and neurological medication. In conclusion, a directive for dispensing of MCAs in pharmacies by pharmacists through an enhanced service should be elaborated having in consideration PIMs, SDIs, drug stability and use of externals and MCA design and brand.
Wed, 22 July 2020
REVIEW | doi:10.20944/preprints202007.0519.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Burn wounds; ZnO NPs; Plant-based Green Synthesis; Wound healing
Online: 22 July 2020 (11:10:15 CEST)
In this changing world, we all are surrounded by the surmountable risk of getting injured. Amongst various risk factors, major burns are the most distressing and catastrophic. Burn wounds are not easy to heal via natural healing process and ultimately ended up with scar formation. If the degree of burn is high then the loss of tissue and its function is very common. To fasten-up the natural burn wound healing; zinc, an essential trace element is found to be very much effective. But due to its’ particle size limitation, less contact with wounded cells and tissues, and high inherent toxicity restrict its use. Needlessly, zinc is an element with dual action i.e. both antimicrobial and wound healing it is a prime choice to apply its aptitude in burn wound healing. To overcome the documented limitations zinc has converted to nanoparticle form. Zinc oxide nanoparticles, in particular, have attained ample of interest due to their unique properties and potential antimicrobial activity along with wound healing activity which makes it promising for the healing of topical burn wounds. Plant mediated green synthesis of nano-metal oxide particles is gaining a lot of significance due to its simplicity, eco-friendliness and extensive antimicrobial activity and recommended as an appealing substitute to not only physical methods but also chemical methods avoiding the use of the high rate of toxic chemicals and extreme surroundings. This study includes ZnO NPs role in burn wound healing with Phyto-mediated synthesis methods to provide evidence of their potential applications. Additionally, it provides an overview of traditional methods used for the synthesis of ZnO nanoparticles and characterization techniques to obtain information concerning the size, shape and optical properties along with toxicity and safety concern of ZnO NPs and its biomedical applications.
Sun, 12 July 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: ozone therapy; ozonized saline solution; SARS-CoV-2; COVID-19; pneumonia
Online: 12 July 2020 (16:30:51 CEST)
Currently, there is no effective antiviral therapy recommended for the new coronavirus disease 2019 pneumonia (COVID-19). The purpose of this pilot study was to evaluate the safety of Ozonized Saline Solution (O3SS) used as a complementary therapy in adult patients COVID-19. Twenty-five adult patients who were hospitalized with mild to severe COVID-19 symptoms, who met the inclusion criteria and were being treated from April 18rd to April 26th, 2020, at the Viamed Virgen De La Paloma Hospital, Madrid, Spain were included in this study. Patients were allocated to receive standard care (SC) that included 200-400 mg hydroxychloroquine twice daily for 5-7 days plus Tocilizumab 400 mg twice daily for 5 days, low molecular weight heparin (LMWH) and 40 mg-60 mg metil-prednisone plus O3SS, 200 mL, 3-5 µg/mL daily for 10 days. No control group was included, data were compared to clinical trials in this subject. Primary outcomes of treatment with O3SS were an improvement of clinical symptoms and a reduction in mortality. Secondary end points evaluated included participant clinical status, laboratory examinations, and duration of viral shedding. None of the patients treated with SC + O3SS died. Improvements in symptoms such as dyspnea, weakness, and reduction in body temperature were observed and corresponded with an improvement of laboratory finding including D-dimer, fibrinogen, LDH, and CRP. No side effects from the O3SS treatment were observed. Conclusions: COVID-19 patients with mild to severe symptoms who received intravenous O3SS as a complementary therapy demonstrated no side effects. This preliminary data will be served as base for a future study of the efficacy of this therapy.
Fri, 3 July 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: ozone therapy; ozonized saline solution; SARS-CoV-2; COVID-19; pneumonia
Online: 3 July 2020 (08:46:48 CEST)
Currently, there is no effective antiviral therapy recommended for the new coronavirus disease 2019 pneumonia (COVID-19). The purpose of this pilot study was to evaluate the safety of Ozonized Saline Solution (O3SS) used as a complementary therapy in adult patients COVID-19. Twenty-five adult patients who were hospitalized with mild to severe COVID-19 symptoms, who met the inclusion criteria and were being treated from April 3rd to April 26th, 2020, at the Viamed Virgen De La Paloma Hospital, Madrid, Spain were included in this study. Patients were allocated to receive standard care (SC) that included 200-400 mg hydroxychloroquine twice daily for 5-7 days plus Tocilizumab 400 mg twice daily for 5 days, low molecular weight heparin (LMWH) and 40 mg-60 mg metil-prednisone plus O3SS, 200 mL, 3-5 µg/mL daily for 10 days. Non control group was included, data were compared to clinical trials in this subject. Primary outcomes of treatment with O3SS were an improvement of clinical symptoms and a reduction in mortality. Secondary end points evaluated included participant clinical status, laboratory examinations, and duration of viral shedding. None of the patients treated with SC + O3SS died. Improvements in symptoms such as dyspnea, weakness, and reduction in body temperature were observed and corresponded with an improvement of laboratory finding including D-dimer, fibrinogen, LDH, and CRP. No side effects from the O3SS treatment were observed. Conclusions: COVID-19 patients with mild to severe symptoms who received intravenous O3SS as a complementary therapy demonstrated no side effects. This preliminary data will be served as base for a future study of the efficacy of this therapy.
REVIEW | doi:10.20944/preprints202007.0016.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: myeloma; BCMA; bispecific T-cell engager; antibody-drug conjugates; chimeric antigen receptor T-cells; belantamab mafodotin; idecabtagene vicleucel; JNJ-68284528
Online: 3 July 2020 (07:30:57 CEST)
During the past two decades there has been a major shift in the choice of agents to treat multiple myeloma, whether newly diagnosed or in the relapsed/refractory stage. The introduction of new drug classes, such as proteasome inhibitors, immunomodulators, and anti-CD38 and anti-SLAMF7 monoclonal antibodies, coupled with autologous stem cell transplantation, have approximately doubled the disease’s five-year survival rate. However, this positive news is tempered by the realization that these measures are not curative and patients eventually relapse and/or become resistant to the drug’s effects. Thus, there is a need to discover newer myeloma-driving molecular markers and develop innovative drugs designed to precisely regulate the actions of such putative targets. B cell maturation antigen (BCMA), which is found almost exclusively on the surfaces of malignant plasma cells to the exclusion of other cell types, including their normal counterparts, has emerged as a specific target of interest in this regard. Immunotherapeutic agents have been at the forefront of research designed to block BCMA activity. These agents encompass monoclonal antibodies, such as the drug conjugate belantamab mafodotin; bispecific T-cell engager strategies exemplified by AMG 420; and chimeric antigen receptor (CAR) T-cell therapeutics that include idecabtagene vicleucel (bb2121) and JNJ-68284528.
HYPOTHESIS | doi:10.20944/preprints202007.0015.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: coronavirus; Substance P/Neurokinin-1 Receptor; respiratory illness; Infectious disease; trigeminal ganglion
Online: 3 July 2020 (05:54:18 CEST)
Novel severe acute respiratory syndrome coronavirus 2 infection (SARS-Cov-2) is an acute respiratory and infectious disease. This perspective aims to provide the basic understanding of the inflammation caused by SARS-Cov-2 and relation to trigeminal ganglion (TG). Virus enters through the mucous membranes of orofacial region and reach the TG where it resides and take control of its peptides including Substance P (SP).SP is the main neuropeptide, neuromodulator and neuro-hormone of TG, associated with nociception and inflammation under noxious stimulus. SP release is triggered and consequently, it affects the immune cells, blood vessels to release the mediators for inflammation. Cytokine storming is initiated and cause respiratory distress, bronchoconstriction and death in complicated cases. Neurokinin-1 Receptor (NK-1R) antagonist and glucocorticoids may be used to alleviate the symptoms and treat this infection. SP is the main culprit seem to be involved in the triggering of inflammatory pathways in SARS-Cov-2 infection. It has direct association with cardiorespiratory rhythm, sleep-wake cycle, nociception, ventilator responses and regulates many important physiological and pathological roles. Its over-secretion should be blocked by NK-1R antagonist. However, experimental work leading to clinical trials are mandatory for further confirmation.
Sun, 28 June 2020
ARTICLE | doi:10.20944/preprints202006.0335.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Self-medication; dispensing; drug; prescription; misuse; Libya
Online: 28 June 2020 (10:03:59 CEST)
Background and Objectives: In Libya, prescription medicines can easily be dispensed without a prescription, as self-medication with the subsequent of potential misuse and unnecessary risk for patients. This systematic review and meta-analysis explored the prevalence of self-medication among citizens in Libya. Methods: We systematically searched PubMed, ISI Web of Knowledge, EMBASE, Medline, Scopus, google scholar and ResearchGate databases for studies published in Libya reporting the prevalence of non-prescription use of medicines in community pharmacies, targeting studies published from Jan 2008 until Dec 2019. A random meta-analysis was performed to analyze pooled estimates of non-prescription usage of medicines. Results: Out of 63 articles identified, a total of 13 papers from 7 cities were met the inclusion criteria and involved a total of 4741 subjects. The overall pooled proportion of self-medication of drugs was 53.6% (95% CI: 0.93% - 1.08%), with low heterogeneity and the P-value of the whole population tasted was found to be = 1.000 (df = 12). Seven out of the 13 studies reported data on self-medication for antibiotics without prescription. The records ranged from 15.3% (95% CI 0.61–1.65) in Misurata to 76.6% (95% CI 0.80–1.25) in Tripoli. Conclusion: Self-medication use of medicines among Libyan population is a common phenomenon involving a high proportion use of antibiotics. This misuse of medications could enhance the development and spread of antibiotic resistance.
Thu, 18 June 2020
ARTICLE | doi:10.20944/preprints202006.0233.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: ozone therapy; ozonized saline solution; SARS-CoV-2; COVID-19; pneumonia
Online: 18 June 2020 (13:13:39 CEST)
Currently, there is no effective antiviral therapy recommended for the new coronavirus disease 2019 pneumonia (COVID-19). The purpose of this study was to evaluate the safety and efficacy of Ozonized Saline Solution (O3SS) used as a complementary therapy in adult patients with mild to severe COVID-19. Twenty-five adult patients who were hospitalized with mild to severe COVID-19 symptoms, who met the inclusion criteria and were being treated from April 3rd to April 26th, 2020, at the Viamed Virgen De La Paloma Hospital, Madrid, Spain were included in this study. Patients were allocated to receive standard care (SC) that included 200-400 mg hydroxychloroquine twice daily for 5-7 days plus Tocilizumab 400 mg twice daily for 5 days, low molecular weight heparin (LMWH) and 40 mg-60 mg metil-prednisone plus O3SS, 200 mL, 3-5 µg/mL daily for 10 days. Primary outcomes of treatment with O3SS were an improvement of clinical symptoms and a reduction in mortality. Secondary end points evaluated included participant clinical status, laboratory examinations, and duration of viral shedding. None of the patients treated with SC + O3SS died. Improvements in symptoms such as dyspnea, weakness, and reduction in body temperature were observed and corresponded with an improvement of laboratory finding including D-dimer, fibrinogen, LDH, and CRP. No side effects from the O3SS treatment were observed. Conclusions: COVID-19 patients with mild to severe symptoms who received intravenous O3SS as a complementary therapy demonstrated improved clinical symptoms, improved laboratory values and a reduction in mortality.
REVIEW | doi:10.20944/preprints202006.0232.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Adverse drug reactions; Anti-COVID drugs; Coronavirus; Drug repurposing; Drug toxicity; Pharmacotherapy
Online: 18 June 2020 (12:43:43 CEST)
Coronavirus disease (COVID-19) is the current global public health threat with no specific, effective, and approved treatment available till date. The outbreak of COVID-19 has led the world into an unimagined and uncertain situation by disrupting the economies, claiming human lives, and leaving many into secondary mental health problems. As per the latest WHO report, approximately 8.2 million people are infected, and nearly 0.44 million lives are lost to COVID. The infection has spread to over 200 countries and territories around the world. The world is in search of efficient diagnostics and therapeutics, including vaccines, biologics and drugs. With the rapid increase in rates of infection and time constraints, drug repurposing seems to be a potential and viable option to find the promising anti-COVID therapeutics. In the wake of a rapid increase in the number of clinical trials involving drugs for repurposing, we aim to provide information on the safety concerns related to the drugs currently investigated in trials. This review also highlights the possible mechanisms of actions, adverse drug reactions, and contraindications of the drugs under repurposing evaluation.
Fri, 12 June 2020
ARTICLE | doi:10.20944/preprints202006.0150.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: cognitive impairment screening; cognitive reserve; subjective memory complaints; Internet; television; reading; marital status; sleep.
Online: 12 June 2020 (12:25:24 CEST)
Subjective cognitive decline (SCD) would correspond to a preclinical phase of Alzheimer's disease. The aim of this study was to find associations between lifestyle individual factors compatible scores with cognitive impairment (CI) in SCD people. Methods: This is a case-control study to detect SCD, CI and potential associated factors in 497 patients over 50 years in Community Pharmacies. Three screening tests detected possible CI and patients with at least one test compatible with CI were referred to Primary Care to be evaluated. Results: In self-complaint patients statistically significant with depressive feelings were found (86.8%) with benzodiazepines consumers (83.9%) and female patients (81.2%). Thirty percent of our sample obtained scores compatible with CI. Being older than 70 years old increased the odds of obtaining scores compatible with CI. High level education, reading and internet use were able to reduce the odds of positive scores compatible with CI (37%-91%, 7%-18% and 67%-86%), whereas, one extra hour television/day increased the risk in 8%-30%. Reading was able to nullify the effect of both internet and TV consumption. Conclusion: Not just the age but also modifiable lifestyle factors are acting in favour of a cognitive decline.
Wed, 10 June 2020
REVIEW | doi:10.20944/preprints201909.0234.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: neurobehavioral assessment; ecotoxicology; zebrafish; neurotoxicology
Online: 10 June 2020 (05:24:07 CEST)
The industry is increasingly relying on fish for toxicity assessment. However, current guidelines for toxicity assessment focus on teratogenicity and mortality. From an ecotoxicological point of view, however, these endpoints may not reflect the “full picture” of possible deleterious effects that can nonetheless result in decreased fitness and/or inability to adapt to a changing environment, affecting whole populations. Therefore, assessing sublethal effects add relevant data covering different aspects of toxicity at different levels of analysis. Impacts of toxicants on neurobehavioral function have the potential to affect many different life-history traits, and are easier to assess in the laboratory than in the wild. We propose that carefully-controlled laboratory experiments on different behavioral domains – including anxiety, aggression, and exploration – can increase our understanding of the ecotoxicological impacts of contaminants, since these domains are related to traits such as defense, sociality, and reproduction, directly impacting life-history traits. The effects of selected contaminants on these tests are reviewed, focusing on larval and adult zebrafish, showing that these behavioral domains are highly sensitive to small concentrations of these substances. These strategies suggest a way forward on ecotoxicological research using fish.
Tue, 9 June 2020
ARTICLE | doi:10.20944/preprints202006.0122.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Hepatoprotective; ascorbic acid; α-tocopherol; paracetamol; ALT; MDA; Histology
Online: 9 June 2020 (11:40:38 CEST)
Background and objectives: The hepatoprotective activity of vitamin E and C is evident due to their ability of modulating the antioxidant pathway. In this study, we have evaluated the effects of α-tocopherol and ascorbic acid on paracetamol induced liver damage with offsetting various levels of drug treatment following an in vivo experimental protocol on Wistar albino male rats. Materials and Methods: The level of lipid peroxidation as well as histological examination of liver tissues were observed among 50 Wistar albino male rats to evaluate hepatoprotective effect of α-tocopherol and ascorbic acid on hepatocytes. The experiment was divided into 5 groups (10 rats in each group)- Basal control group (Group-I, with propylene glycol), Paracetamol treated control group (Group –II), α-tocopherol pretreated & paracetamol treated group (Group –III), Ascorbic acid pretreated & paracetamol treated group (Group –IV) and Ascorbic acid pretreated & paracetamol treated group (Group –IV). Results: The mean (± SD) Malondialdehyde (MDA) concentration were significantly reduced in α-tocopherol pretreated and paracetamol treated group (P<0.001), Ascorbic acid pretreated and paracetamol treated group (P≤0.05) and combined α-tocopherol with ascorbic acid pretreated & paracetamol treated group (P<0.001). Statistically significant differences in histological findings of rat liver were observed in paracetamol treated control group (P<0.001), ascorbic acid pretreated and paracetamol treated group (P<0.001). The serum alanine aminotransferase (ALT) level was also significantly higher in paracetamol treated group (P<0.001), α-tocopherol pretreated plus paracetamol treated group (P≤0.05) and in ascorbic acid pretreated plus paracetamol treated group (P<0.001). Conclusion: The combined pretreatment of α-tocopherol & ascorbic acid have better hepatoprotective effects than α-tocopherol or ascorbic acid alone against paracetamol induced liver damage. The decrement of free radicals produced by vitamin E could be a better hepatoprotective antioxidant than vitamin C in paracetamol induced toxicity.
Sun, 7 June 2020
ARTICLE | doi:10.20944/preprints202006.0107.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Ang II; COVID19; erythropoietin; EPO-R
Online: 7 June 2020 (16:21:35 CEST)
Neuroinflammation, defined as inflammatory reactions mediated by cytokines, chemokines, reactive oxygen species, and secondary messengers in the central nervous system (CNS) including the brain and spinal cord is the basis of many neurological disorders  Recently, erythropoietin (EPO) has been considered and studied as a modulator of neuroinflammation.[2-4] On this article minireview of pathophysiology of neuroinflammation and the neuroprotective effects of EPO is discussed and a case of subacute huge subdural hematoma with double mydriasis operated urgently, treated with low daily dose (vs high dose once or twice a month in the literature) of EPO and recovered fully and discharged home with good consciousness is reported. In addition, the probable outcome of erythropoietin administration in patients with neuroinflammation in COVID19 is considered.
Mon, 1 June 2020
ARTICLE | doi:10.20944/preprints202004.0161.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; docking; drug repurposing; natural products; in silico drug design; viral replication inhibition
Online: 1 June 2020 (02:42:54 CEST)
We use state-of-the-art computer-aided drug design (CADD) techniques to identify prospective inhibitors of the main protease enzyme, 3CLpro of the SARS-CoV-2 virus causing COVID-19. From our screening of over one million compounds including approved drugs, investigational drugs, natural products, and organic compounds, and a rescreening protocol incorporating enzyme dynamics via ensemble docking, we have been able to identify a range of prospective 3CLpro inhibitors. Importantly, some of the identified compounds had previously been reported to exhibit inhibitory activities against the 3CLpro enzyme of the closely related SARS-CoV virus. The top- ranking compounds are characterized by the presence of multiple bi- and monocyclic rings, many of them being heterocycles and aromatic, which are flexibly linked allowing the ligands to adapt to the geometry of the 3CLpro substrate site and involve a high amount of functional groups enabling hydrogen bond formation with surrounding amino acid residues, including the catalytic dyad residues H41 and C145. Among the top binding compounds we identified several tyrosine kinase inhibitors, which include a bioflavonoid, the group of natural products that binds best to 3CLpro. Another class of compounds that decently binds to the SARS-CoV-2 main protease are steroid hormones, which thus may be endogenous inhibitors and might provide an explanation for the age-dependent severity of COVID-19. Many of the compounds identified by our work show a considerably stronger binding than found for reference compounds with in vitro demonstrated 3CLpro inhibition and anticoronavirus activity. The compounds determined in this work thus represent a good starting point for the design of inhibitors of SARS-CoV-2 replication.
Sun, 31 May 2020
REVIEW | doi:10.20944/preprints202005.0510.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: psychedelics; neuroimaging; consciousness
Online: 31 May 2020 (20:53:59 CEST)
Serotonergic psychedelics are known to elicit changes in conscious awareness, including perception of the environment and the self, as well as in mood, emotion and different aspects of cognition (Nichols, 2016). The effect of these compounds is complex and resists a straightforward classification that is useful for other drugs, such as “stimulants” or “sedatives”. While the effects of certain psychedelics do have a stimulant dimension, their defining characteristic is the capacity to temporarily induce a state of altered consciousness. Because of this, the study of psychedelics cannot be based only on animal models, since humans are alone in their capacity to explicitly report the contents of their conscious awareness. Psychedelic research with healthy human subjects necessitates techniques for the non-invasive recording of brain activity or its physiological and metabolic correlates. These techniques are referred to as “neuroimaging”, and here we review their application in the study of the neural correlates of altered consciousness induced by serotonergic psychedelics.
Fri, 29 May 2020
ARTICLE | doi:10.20944/preprints202004.0457.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Covid-19; desmosine; dp-ucMGP; elastic fibers; factor II; matrix Gla protein; PIVKA-II; protein S; vitamin K; vitamin K antagonist
Online: 29 May 2020 (04:16:20 CEST)
Background: A significant proportion of SARS-CoV-2-infected patients develops respiratory failure. Thromboembolism is also prevalent in coronavirus disease 2019 (Covid-19). Vitamin K plays a role in coagulation and possibly also in lung diseases. We therefore hypothesized that vitamin K is implicated in Covid-19 pathogenesis. Methods: 134 Covid-19 patients and 184 controls were included. Inactive vitamin K-dependent matrix Gla protein (i.e.dp-ucMGP) and prothrombin (i.e. PIVKA-II) were measured, which are inversely related to respectively extrahepatic and hepatic vitamin K status. Desmosine was measured to quantify elastic fiber degradation. Lung involvement and arterial calcifications severity were assessed by computed tomography. Results Dp-ucMGP was elevated in Covid-19 patients compared to controls (P=0.001). Higher dp-ucMGP was found in Covid-19 patients with poor compared to better outcomes (P=0.002). PIVKA-II was normal in 81.8%, mildly elevated in 14.0% and moderately elevated in 4.1% of Covid-19 patients not using vitamin K antagonists. Dp-ucMGP in Covid-19 patients was correlated with desmosine (P<0.001), thoracic aortic calcification (P<0.001) but not with pneumonia severity. Conclusions: Extrahepatic vitamin K status was severely reduced in Covid-19 patients, as reflected by elevated inactive MGP, and related to poor outcome. Procoagulant prothrombin activity remained preserved in the majority of Covid-19 patients, which is compatible with the increased thrombogenicity that is frequently observed in severe Covid-19. Impaired MGP activation was linked to accelerated elastic fiber degradation and premorbid vascular calcifications. A trial should assess whether increasing MGP and protein S activity by vitamin K administration improves Covid-19 outcomes.
Mon, 25 May 2020
REVIEW | doi:10.20944/preprints202005.0408.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: drug discovery; machine learning; in silico; pharmacology
Online: 25 May 2020 (04:55:24 CEST)
The vastness of chemical-space constrains traditional drug-discovery methods to the organic laws that are guiding the chemistry involved in filtering through candidates. Leveraging computing with machine-learning to intelligently generate compounds that meet a wide range of objectives can bring significant gains in time and effort needed to filter through a broad range of candidates. This paper details how the use of Generative-Adversarial-Networks, novel machine learning techniques to format the training dataset and the use of quantum computing offer new ways to expedite drug-discovery.
Sun, 24 May 2020
REVIEW | doi:10.20944/preprints202005.0392.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: RAAS inhibitors; COVID-19; coronavirus; angiotensin; clinical outcome; antihypertensive
Online: 24 May 2020 (17:48:42 CEST)
Since the effects of renin–angiotensin–aldosterone system (RAAS) inhibitors on the clinical outcomes of coronavirus disease-19 (COVID-19) have been conflicting in different studies, we performed this meta-analysis. A systematic search of published articles was performed in PubMed and EMBASE from January-May 5, 2020. Studies that reported the clinical outcomes of patients with COVID-19, stratified by the class of concomitant antihypertensive drug therapy, were included. The Mantel-Haenszel random effects model was used to estimate pooled odds ratio (OR). A total of 6,997 hypertensive patients with COVID-19 were included. The overall risk of poor patient outcomes (severe COVID-19 or death) was lower in patients taking RAAS inhibitors (OR=0.84, 95% CI: [0.73, 0.96]; P=0.017) compared with those receiving non-RAAS inhibitor antihypertensives. Patients taking angiotensin-I-converting enzyme inhibitors (ACEIs) were less likely to experience poor clinical outcomes (OR=0.73, 95% CI: [0.58-0.92]; P=0.01) compared with those receiving angiotensin-II receptor blockers (ARBs). Compared to all other antihypertensives, ACEIs decreases the risk poor COVID-19 outcomes (OR=0.77, 95% CI: [0.63-0.93]) while ARBs did not (OR=1.13, 95% CI: [0.95-1.35]). The risk of poor patient outcomes from COVID-19 was lower in patients who received RAAS inhibitors compared with those who took non-RAAS inhibitors. Unlike ARBs, ACEIs might help in decreasing the severity and mortality of COVID-19.
Thu, 21 May 2020
REVIEW | doi:10.20944/preprints202005.0342.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: seaweed; metabolites; neuroprotection; Alzheimer’s disease; Parkinson’s disease; ischemic stroke; computer-aided drug discovery
Online: 21 May 2020 (09:49:29 CEST)
Beyond their significant contribution to the dietary and industrial supplies, marine algae are considered to be a potential source of some unique metabolites with diverse health benefits. The pharmacological properties, such as antioxidant, anti-inflammatory, cholesterol homeostasis, protein clearance and anti-amyloidogenic potentials of algal metabolites endorse their protective efficacy against oxidative stress, neuroinflammation, mitochondrial dysfunction, and impaired proteostasis which are known to be implicated in the pathophysiology of neurodegenerative disorders and the associated complications after cerebral ischemia and brain injuries. As was evident in various preclinical studies, algal compounds conferred neuroprotection against a wide range of neurotoxic stressors, such as oxygen/glucose deprivation, hydrogen peroxide, glutamate, amyloid β, or 1-methyl-4-phenylpyridinium (MPP+) and, therefore, hold therapeutic promise for brain disorders. While a significant number of algal compounds with promising neuroprotective capacity have been identified over the last decades, a few of them have had access to clinical trials. However, the recent approval of an algal oligosaccharide, sodium oligomannate, for the treatment of Alzheimer's disease enlightened the future of marine algae-based drug discovery. In this review, we briefly outline the pathophysiology of neurodegenerative diseases and brain injuries for identifying the targets of pharmacological intervention, and then review the literature on the neuroprotective potentials of algal compounds along with the underlying pharmacological mechanism, and present an appraisal on the recent therapeutic advances. We also propose a rational strategy to facilitate algal metabolites-based drug development.
REVIEW | doi:10.20944/preprints202005.0340.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Cannabidiol; Alzheimer's disease; Huntington's disease; Multiple sclerosis; Parkinson’s disease; Prion disease; Proteinopathies
Online: 21 May 2020 (09:43:09 CEST)
Cannabidiol is a well-known non-psychotropic phytocannabinoid from Cannabis sativa, which exerts a broad range of neuropharmacological activities in the central nervous systems. Over the past years, compelling evidence from preclinical and clinical studies support therapeutic potentials of cannabidiol in various neurological disorders, including neurodegenerative diseases. Neurodegenerative diseases are characterized by the accumulation of misfolded or aggregated protein due to the defective protein homeostasis or proteostasis network, termed as proteinopathies. Because of its role in the protein homeostasis network, cannabidiol could be a potent molecule to revert not only age-associated neurodegeneration but also other protein misfolding disorders. In this review, we discuss the potentiality of cannabidiol as a pharmacological modulator of the proteostasis network, highlighting its neuroprotective and aggregates clearing system inducing potentials in the neurodegenerative diseases.
Tue, 19 May 2020
ARTICLE | doi:10.20944/preprints202005.0308.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Oral health care products; cyclooxygenase; lipoxygenase; periodontal disease; Candida albicans; Candida glabrata; medicinal herbs
Online: 19 May 2020 (03:45:56 CEST)
Background: Given the increasing request for natural pharmacological molecules, this study assessed the antimicrobial capacity of Pistacia lentiscus L. essential oil (PLL-EO) obtained from the leaves of wild plants growing in North Sardinia (Italy), toward a wide range of periodontal bacteria and Candida including laboratory and clinical isolates sp., together with its anti-inflammatory activity and safety; Methods: PLL-EO was screened by gas chromatography / mass spectrometry. The minimal inhibitory concentration (MIC) was determined. The anti-inflammatory activity was measured by cyclooxygenase (COX 1/2) and lipoxygenase (LOX) inhibition while the antioxidant capacity was determined electro-chemically and by the MTT assay. The WST-1 assay was used to ascertain cytotoxicity toward four line of oral cells; Results: According to the concentrations of terpens, PLL-EO is a pharmacologically active phytocomplex. MICs against periodontal bacteria ranged between 3.13 and 12.5 µg/ml, while against Candida sp. were between 6.25 and 12.5 µg/ml. Oxidation by COX 1/2 and LOX was inhibited by 80% and 20% µg/mL of the oil respectively. Antioxidant activity seemed negligible, and no cytotoxicity arose; Conclusions: PLL-EO exhibits a broad-spectrum activity against periodontal bacteria and Candida, with an interesting dual inhibitory capacity toward COX2 and LOX inflammatory enzymes and without side effects against oral cells.
Mon, 18 May 2020
REVIEW | doi:10.20944/preprints202005.0295.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: coronaviruses; plants metabolites; polyphenols; antiviral-effect
Online: 18 May 2020 (04:09:48 CEST)
Coronaviruses such as SARS (severe acute respiratory syndrome), MERS (Middle East respiratory syndrome), and newly emerged SARS-CoV-2, also called 2019-nCoV and COVID 19, have caused worldwide outbreaks in different time periods. There are many studies about chemical and natural drugs to treat these coronaviruses by inhibiting their proteases or their protein receptors through binding to amino acid residues. Plants secondary and primary metabolites are considered as potential drugs to inhibit various types of coronaviruses. IC50 value (the concentration in which there is 50% loss in enzyme activity) and molecular docking score and binding energy are parameters to understand the metabolites ability to inhibit the specific virus. In this study we did review on more than 110 papers on plant metabolites effect on different coronaviruses. Secondary plant metabolites such as polyphenols (flavonoids, coumarins, stilbenes), alkaloids, terpenoids, organosulfur compounds saponins, saikosaponins, lectins, essential oils, nicotianamine and primary metabolites such as vitamins.
Sun, 10 May 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; redmdesivir; cholorquine; therapy; SARS-CoV-2
Online: 10 May 2020 (18:26:04 CEST)
On 11 March 2020, the coronavirus disease (COVID-19) was defined by the World Health Organization as a pandemic. Severe acute respiratory syndrome-2 (SARS-CoV-2) is the newly evolving human coronavirus infection, causing (COVID-19), first appeared in Wuhan, China in December 2019 and spread rapidly all over the world. COVID-19 is being increasingly investigated in virology, epidemiology, and clinical management strategies. There is currently no established consensus on the standard of care in the pharmacological treatment of COVID-19 patients. However, certain medications suggested for other diseases tend to be potentially effective for treating this infection, although, so far, without clear evidence. Therapies include new agents which are currently tested in several clinical trials, in addition to other medications that have been repurposed as antiviral and immune-modulating therapies. Previous high-morbidity human coronavirus epidemics such as the 2003 SARS-CoV and the 2012 Middle East respiratory syndrome coronavirus (MERS-CoV) prompted the identification of compounds that could theoretically be active against the emerging coronavirus SARS-CoV-2. Moreover, the advances in molecular biology techniques and computational analysis allowed better recognition of the virus structure and quicker screening of chemical libraries to suggest potential therapies. This review aims to summarize rationalized pharmacotherapy considerations in COVID-19 patients, to serve as a tool for health care professionals at the forefront of clinical care during this pandemic. All the therapies reviewed require either additional drug development or randomized large-scale clinical trials to be justified for clinical use.
REVIEW | doi:10.20944/preprints202005.0178.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; estrogen; RAGE; ACE2
Online: 10 May 2020 (17:46:13 CEST)
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has provoked major stresses on the health care systems of several countries, and caused the death of more than a quarter of a million people globally, mainly in the elderly population with pre-existing pathologies. Previous studies with coronavirus (SARS-CoV) point to gender differences in infection and disease progression with increased susceptibility in male patients, indicating that estrogens may be associated with physiological protection against the coronavirus. Therefore, the objectives of this work are threefold. First, we aim to summarize the SARS-CoV-2 infection pathway and the roles both the virus and patient play in COVID-19 (Coronavirus disease 2019) progression, clinical symptomology, and mortality. Second, we detail the effect estrogen has on viral infection and host infection response, including its role in both the regulation of key viral receptor expression and the mediation of inflammatory activity. Finally, we describe how ERs (estrogen receptors) and RAGE (receptor for advanced glycation end-products) play a critical role in metabolic pathways, which we envisage could maintain a close interplay with SARS-CoV and COVID-19 mortality rates, despite a current lack of research directly determining how. Taken together, we present the current state of the field regarding SARS-CoV-2 research and illuminate where research is needed to better define the role both estrogen and metabolic comorbidities have in the COVID-19 disease state, which can be key in screening potential therapeutic options as the search for effective treatments continue.
Wed, 6 May 2020
ARTICLE | doi:10.20944/preprints202005.0102.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: marine natural products; Laurencia; brominated sesquiterpenes; antimycobacterial; nontuberculous mycobacteria; tuberculosis
Online: 6 May 2020 (15:32:53 CEST)
Marine environments represent a great opportunity for the discovery of compounds with a wide spectrum of bioactive properties. Due to the privileged conditions of natural selection, marine natural products are subject to overcome the pressure put on identify novel drugs; not only in the case of newly discovered bioactive metabolites, but also in those previously known. Since drug resistance has caused an increase in infections caused by tuberculous and nontuberculous Mycobacteria, the re-evaluation of known bioactive metabolites has been suggested as a means to address this problem. In this sense, this study presents an evaluation of in vitro effect of laurinterol (1) and aplysin (2), two brominated sesquiterpenes isolated from Laurencia johnstonii against nine Mycobacterium tuberculosis strains and six nontuberculous mycobacteria. Laurinterol (1) exhibited good anti-tuberculous activity, especially against nontuberculous mycobacteria, being remarkable the effect against M. abscessus with MIC values lower than the reference drug imipenem. This study provides further evidence for the antimycobacterial activity of some sesquiterpenes from L. johnstonii, that can be considered an interesting lead compound for the discovery of novel antimycobacterial molecules to treat NTM infections.
Tue, 5 May 2020
HYPOTHESIS | doi:10.20944/preprints202005.0061.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: SARS-CoV-2; COVID-19; Lysosomotropism; Chloroquine
Online: 5 May 2020 (04:29:48 CEST)
The COVID-19 pandemic is one of the largest challenges in medicine and health care worldwide in recent decades, and it is infecting and killing increasing numbers of people every day. In this paper, we discuss the possible relationships among lysosomotropism, increasing lysosomal pH, and the SARS-CoV-2 infection and disease process, and we deduce a possible approach for treatment and prophylaxis. Lysosomotropism is a biological characteristic of small molecules, such as (hydroxyl)chloroquine, amitriptyline, NB 06, or sertraline, which is present in addition to intrinsic receptor-mediated or enzymatic pharmacological effects. Lysosomotropic compounds affect prominent inflammatory messengers, such as IL1B, CCL4, CCL20, and IL6, as well as cathepsin L dependent viral entry (fusion) into host cells. Therefore, this heterogeneous group of compounds is a promising candidate for the prevention and treatment of SARS-CoV-2 infections, as well as influenza A infections and cytokine release syndrome (CRS) triggered by bacterial or viral infections. Patients who have already taken medications with lysosomotropic compounds for other pre-existing conditions may benefit from this treatment in the COVID-19 pandemic. Increased lysosomal pH levels play an important role in the disease process in common skin disorders, such as psoriasis and atopic dermatitis, thus suggesting that affected individuals might benefit from their particular conditions in the COVID-19 pandemic. We suggest data analysis of patients with these diseases, and who are treated with lysosomotropic compounds, and, if the results are promising, subsequent clinical testing of off-label therapy with clinically approved lysosomotropic compounds in the current COVID-19 pandemic and future influenza A pandemics.
Sat, 25 April 2020
ARTICLE | doi:10.20944/preprints202004.0457.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; vitamin K; vitamin K antagonists; SARS-CoV-2; matrix Gla protein; desmosine; protein C; protein S
Online: 25 April 2020 (03:13:45 CEST)
Introduction: Coronavirus 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus-2. The majority of patients have at most mild symptoms, however, a significant proportion develops respiratory failure. COVID-19 may also progress beyond the lungs. Coagulopathy and thromboembolism are prevalent in severe COVID-19 and relate to decreased survival. Coagulation is an intricate balance between clot promoting and dissolving processes in which vitamin K plays a well-known role. We hypothesized that vitamin K status is reduced in patients with severe COVID-19. Methods: Vitamin K status was assessed by measuring desphospho-uncarboxylated matrix Gla protein (dp-ucMGP; inversely related to vitamin K status) and the rate of elastin degradation by measuring desmosine. We included 123 patients who were admitted with COVID-19 and 184 controls. Results: Dp-ucMGP levels were significantly elevated in COVID-19 patients (1,673Å}1,584 pmol/L) compared to controls (536±291 pmol/L; p<0.0005). Dp-ucMGP levels were significantly higher in COVID-19 patients with unfavorable outcome compared to those with less severe disease. Furthermore, dp-ucMGP and desmosine levels were significantly associated (r=0.65; p<0.0005). Conclusions: Vitamin K status was reduced in patients with COVID-19 and related to poor prognosis. Also, low vitamin K status seems to be associated with accelerated elastin degradation. An intervention trial is now needed to assess whether vitamin K administration improves outcome in patients with COVID-19.
Fri, 24 April 2020
CONCEPT PAPER | doi:10.20944/preprints202004.0432.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: SARS CoV-2; COVID-19; Nitazoxanide; Azithromycin; Interferons
Online: 24 April 2020 (09:24:23 CEST)
Azithromycin has been shown to have a clinical efficacy against severe acute respiratory syndrome coronavirus 2 (SARS CoV-2); ivermectin has also demonstrated a remarkable experimental efficacy with a potential to be used for Coronavirus disease 2019 (COVID-19). Further, BCG vaccination is being considered for clinical trials aiming to test its potential for lowering COVID-19 morbidity and mortality. This article illustrates some structural and functional relationships that may gather these drugs and the author, basing on a combined pathophysiological and pharmacological approach, recommends the FDA-approved antidiarrhea drug; nitazoxanide, which has been previously suggested but unfortunately ignored, to be tested in combination with azithromycin for their potential activity against SARS CoV-2 soonest. The author recommends testing their combined administration as early during the clinical course of COVID-19 as possible. Further, basing on the same represented concept, the author recommends more trials for interferons to be tested against SARS CoV-2 especially in severe and critical cases.
Wed, 22 April 2020
REVIEW | doi:10.20944/preprints202004.0395.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: coronavirus disease 2019; chloroquine; drug repurposing; HIV; Africa
Online: 22 April 2020 (08:33:34 CEST)
The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2, has been declared by the World Health Organization (WHO) as a pandemic. Unfortunately, finding a vaccine or developing drugs from the scratch is a time-consuming luxury given the widespread and high fatality rates of the virus. In the short term, repurposing of drugs already in use seem to be the most rational step to quickly and effectively curb the virus. Several antiviral agents had been proposed as possible remedies, but the 4-aminoquinolines, Chloroquine (CHQ) and hydroxychloroquine (HCHQ) appear to be generating more interest. They are generic, cheaply available and have proven efficacy against malaria parasites in Africa. The human immunodeficiency virus (HIV), on the other hand, targets the immune system thereby reducing the patient’s ability to fight infections. Sadly, 68% of the global HIV burden occur in Africa. It is therefore anticipated that incidence of severe forms of COVID-19 could occur in Africa because of associated endemic conditions that compromise the immune system. With CHQ and HCHQ being considered for clinical use against COVID-19, there is a need to highlight their potential merits and confounding variables in the subgroup of patients with or without HIV.
Sun, 19 April 2020
ARTICLE | doi:10.20944/preprints202004.0165.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Covid-19; Blastn; toxins protein; ACh; aChE; BuChE; CBP; Zero Point; bungaro-toxins, phospholipase A2; similar prothrombin activator protein
Online: 19 April 2020 (06:51:53 CEST)
Acetylcholine (ACh) is the best one characterized neurotransmitter. Its central roles in the cholinergic areas and central nervous system (CNS) and peripheral (PNS) synapses are well known. It was the first molecule identified as a neurotransmitter and appears to be phylogenetically the oldest one signaling molecules. ACh was detected in bacteria, protozoa, fungi, algae and primitive plants, indicating that the cholinergic system was widely distributed in living organisms before its appearance in the nervous system. The autonomous nervous system (ANS) is an integral part animal kingdom history. It determines fight-escape reactions as well as outlining the vital and cognitive functions bio-organization rhythms. The virus (Covid-19) extraneous effects acting on it could help to better understand its functions. The Blast results show some factors like protein that can be implicated such as bungaro-toxins, phospholipase A2 and the similar prothrombin activator protein. A positive correlation with different toxins is obtained and the Covid-19 double pathogenic mechanism theory is proposed. The process allows us to outline the possibility about toxic-like factors presence.
Fri, 17 April 2020
REVIEW | doi:10.20944/preprints202004.0299.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: SARS-CoV-2; COVID-19; coronavirus; remdesivir
Online: 17 April 2020 (13:02:03 CEST)
The global pandemic of SARS-CoV-2, the causative viral pathogen of COVID-19, has driven the biomedical community to action – to uncover and develop anti-viral interventions. One potential therapeutic approach currently being evaluated in numerous clinical trials is the agent remdesivir, which has endured a long and winding developmental path. Remdesivir is a nucleotide analog prodrug that perturbs viral replication, originally evaluated in clinical trials to thwart the Ebola outbreak in 2014. Subsequent evaluation by numerous virology laboratories demonstrated the ability of remdesivir to inhibit coronavirus replication, including SARS-CoV-2. Here, we provide an overview of its mechanism of action, discovery, and the current studies exploring its clinical effectiveness.
Thu, 16 April 2020
ARTICLE | doi:10.20944/preprints202004.0278.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: cembranoid; inflammation; macrophage; NFkB; adhesion
Online: 16 April 2020 (13:44:33 CEST)
Inflammation is considered an important target for stroke therapy because it induces secondary brain damage after the initial ischemic insult. Peripheral monocytes migrate to the brain parenchyma after a central insult. They then differentiate to macrophages in a positive feedback fashion contributing to damage instead of ischemic resolution and inflammation control. A cyclic diterpenoid, (1S,2E,4R,6R,7E,11E)-cembra-2,7,11-triene-4,6-diol (4R), decreases neurodegeneration after ischemia with central anti-inflammatory activity. This study aims to determine whether the central anti-inflammatory effect of 4R is effective against peripheral inflammation triggered by brain ischemia. To investigate the anti-inflammatory effect of 4R, we treated macrophages with lipopolysaccharide (LPS) as an inflammatory model, followed by treatment with 4R. Microarray transcriptome analysis of over 30,000 genes identified the differential expression of 393 genes. Genes related to inflammation, cell adhesion, and transcription were validated with qPCR, and reduced expression was determined. Quantification of NF-kB phosphorylation served as a marker for the modulation of inflammation through gene transcription. Our results show that 4R was associated with a reduction in NFKB1 and ITGB5 gene expression, increased phosphorylation of NF-kB, and a decrease in macrophage adhesion in a blood-brain barrier model. These results indicate that 4R can partially modulate the peripheral immune response, making 4R a potential drug against post-ischemic inflammation.
Mon, 13 April 2020
SHORT NOTE | doi:10.20944/preprints202004.0208.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: malaria; COVID-19; SARS-COV-2; chloroquine; hydroxychloroquine
Online: 13 April 2020 (07:47:36 CEST)
World is currently experiencing a new pandemic for which no curative treatment is available. At this time, coronavirus disease 2019 (Covid-19) has reached 183 countries and has caused several deaths. Many reports presented chloroquine (CQ) and hydrochloroquine (HCQ), former drugs used against malaria, as the best current choice to fight this terrible disease. As these molecules had been withdrawn in malaria treatment policy due to chemoresistance, their reintroduction could have some consequences. Though local malaria prevalence could decrease for a while, molecular changes are likely to happen on some plasmodium falciparum genes involved in conferring drug resistance. This could threaten efforts in malaria control, if these molecules are widely administered.
REVIEW | doi:10.20944/preprints202004.0207.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Chinese Guidelines; COVID-19; pharmaceutical treatment
Online: 13 April 2020 (03:43:37 CEST)
Background and Objective: China has managed to control the coronavirus disease (COVID-19) with confinement measurements and treatment strategies, while other countries are struggling to contain the spread. This study discusses the guidelines related to COVID-19 in China in order to provide important references for other countries in the fight against COVID-19. Methods: Chinese guidelines relevant to COVID-19 were systematically searched via the China National Knowledge Infrastructure database, YiMaiTong database, and World Health Organization (WHO) COVID-19 database on March 20th, 2020. Guideline information was extracted, including date of publication, source, objectives and the target population. Guidelines specific to the pharmacological treatment of COVID-19 were further investigated to identify the types of antivirus drugs recommended and to report on how treatment recommendations for COVID-19 have evolved overtime. Results: A total of 114 guidelines were identified, of which 87 were national guidelines and 27 were regional guidelines. The scope of included guidelines consisted of: the diagnosis and treatment of COVID-19, the management of hospital departments and specific diseases during the outbreak of COVID-19. Sixty-four of the included guidelines targeted all COVID-19 patients, while the remaining guidelines concentrated on special patient populations (i.e., geriatric population, pediatric population, and pregnant population) or patients with coexisting diseases. Twenty-three guidelines focused on the pharmacological treatments for all COVID-19 patients. Interferon, Lopinavir/Ritonavir, Ribavirin, Chloroquine, and Umifenovir represented the most recommended antivirus drugs. With the emergence of encouraging results from preclinical and preliminary clinical studies, Chloroquine Phosphate was recommended in the national Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia (6th version) on February 19th, 2020. Thereafter, more detailed guidelines regarding the adjustment of dosage regimens and the monitoring of adverse events of Chloroquine Phosphate were published. To date, 8 Chinese guidelines have recommended Chloroquine Phosphate or Hydroxychloroquine as mainstream antivirus drug for the treatment of COVID-19. Conclusions: China has generated a plethora of guidelines covering almost all aspects of COVID-19. Chloroquine, as one widely affordable treatment, holds great potential to become the gold standard choice as more clinical evidence is shared by researchers from China as well as other countries.
Fri, 10 April 2020
ARTICLE | doi:10.20944/preprints202004.0165.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Blastn; toxins protein; ACh; aChE; BuChE; CBP; Zero Point; and bungaro-toxins, phospholipase A2; similar prothrombin activator protein
Online: 10 April 2020 (02:34:36 CEST)
Acetylcholine (ACh) is one of the best characterized neurotransmitters. Its central roles in the cholinergic areas and central nervous system (CNS) and peripheral (PNS) synapses are well known. It was the first molecule identified as a neurotransmitter and appears to be phylogenetically one of the oldest signaling molecules. In fact, ACh was detected in bacteria, protozoa, fungi, algae and primitive plants, indicating that the cholinergic system was widely distributed in living organisms before its appearance in the nervous system. The autonomous nervous system (ANS) is an integral part animal kingdom history. It determines fight-escape reactions as well as outlining the vital and cognitive functions bio-organization rhythms. The virus (Covid-19) extraneous effects acting on it could help to better understand its functions. Through a new deductive and inductive the path axioms are developed and an absurd hypothesis, "natural genetic recombination between different species" is put forward, trying to verify a correlation, tracing what could be the genesis, the "zero-point", crucial and fundamental moment. A positive correlation with different toxins is obtained and the double pathogenic mechanism of Covid-19 theory is proposed. The process allows us to outline the possibility about toxic-like factors presence.
Thu, 9 April 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: adenosine receptor; nucleoside transport; CNS; inflammation; cardiovascular system; pain
Online: 9 April 2020 (16:19:14 CEST)
Many ligands directly target adenosine receptors (ARs). Here we review the effects of noncanonical AR drugs on adenosinergic signaling. Non-AR mechanisms include raising adenosine levels by inhibiting adenosine transport (e.g. ticagrelor, ethanol, cannabidiol), affecting intracellular metabolic pathways (e.g. methotrexate, nicotinamide riboside, salicylate, 5‐aminoimidazole‐4‐carboxamide riboside), or undetermined means (e.g. acupuncture). Yet other compounds bind ARs in addition to their canonical ‘on-target’ activity (e.g. mefloquine). The strength of experimental support for an adenosine-related role in a drug’s effects varies widely. AR knockout mice are the ‘gold standard’ method for investigating an AR role, but few drugs have been tested in these mice. Given the interest in AR modulation for treatment of cancer, CNS, immune, metabolic, cardiovascular, and musculoskeletal conditions, it is informative to consider AR and non-AR adenosinergic effects of approved drugs and conventional treatments.
ARTICLE | doi:10.20944/preprints202004.0161.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; SARS-CoV-2; main protease inhibition; virtual screening; drugs; natural products
Online: 9 April 2020 (14:59:37 CEST)
We use state-of-the-art computer-aided drug design (CADD) techniques to identify prospective inhibitors of the main protease enzyme, Mpro of the COVID-19 virus. With the high-resolution X-ray crystallography structure of this viral enzyme recently being solved, CADD provides a veritable tool for rapidly screening diverse sets of compounds with the aim of identifying ligands capable of forming energetically favorable complexes with Mpro . From our screening of 1,082,653 compounds derived from the ZINC, the DrugBank, and our in-house African natural product libraries, and a rescreening protocol incorporating enzyme dynamics via ensemble docking, we have been able to identify a range of prospective Mpro inhibitors, which include FDA-approved drugs, drug candidates in clinical trials, as well as natural products. The top-ranking compounds are characterized by the presence of an extended ring system combined with functional groups that allow the ligands to adapt flexibly to the Mpro active site as, for example, present in the biflavonoid amentoflavone, one of the most promising compounds identified here. This particular chemical architecture leads to considerable stronger binding than found for reference compounds with in vitro demonstrated M pro inhibition and anticoronavirus activity. The compounds determined in this work thus represent a good starting point for the design of inhibitors of SARS-CoV-2 replication.
Wed, 8 April 2020
REVIEW | doi:10.20944/preprints202004.0115.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: adenosine receptor; nucleoside transport; CNS; inflammationl; cardiovascular system; pain
Online: 8 April 2020 (04:11:27 CEST)
Many ligands directly target adenosine receptors (ARs). Here we review the effects on adenosinergic signaling of other drugs that are not typically identified as binding ARs. Non-AR mechanisms include raising adenosine levels by inhibiting adenosine transport (e.g. ticagrelor, ethanol, cannabidiol), affecting intracellular metabolic pathways (e.g. methotrexate, nicotinamide riboside, salicylate, AICA riboside), or undetermined means (e.g. acupuncture). Yet other compounds bind ARs, in addition to their canonical ‘on-target’ activity (e.g. mefloquine). The strength of experimental support varies widely. AR knockout mice are the ‘gold standard’ method for investigating an AR role, but few drugs have been tested in these mice. Given the interest in AR modulation for treatment of cancer, CNS, immune, metabolic, cardiovascular, and musculoskeletal conditions, it is informative to consider AR and non-AR adenosinergic effects of approved drugs and conventional treatments.
Tue, 7 April 2020
HYPOTHESIS | doi:10.20944/preprints202004.0090.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19: hydroxychloroquine aerosol; pharmacotherapy; prevention; SARS-CoV-2
Online: 7 April 2020 (11:11:09 CEST)
Covid-19 is a new coronavirus disease first described in December 2019. This respiratory illness is severe and potentially fatal. Severe cases make up to 15%, lethality ranges between 1.5 and more than 10 %. What is urgently needed is an efficient pharmacological treatment for the treatment of severe cases. During the infection of alveolar epithelial cells of the lung, the ACE2 receptor has a central function. The antimalarial drugs chloroquine phosphate (CQ) and hydroxychloroquine (HCQ) impair in vitro the terminal glycosylation of ACE2 without significant change of cell-surface ACE2 and, therefore, might be potent inhibitors of SARS-CoV-2 infections. Starting inhibition at 0.1 µM, CQ completely prevented in vitro infections at 10 µM, suggesting a prophylactic effect and preventing the virus spread 5 hours after infection. In a first clinical trial, CQ was effective in inhibiting exacerbation of pneumonia, improving lung imaging findings, promotion of virus-negative conversion, and shortening the disease. In addition, HCQ, which is three times more potent than CQ in SARS-CoV-2 infected cells (EC50 0.72 µM), was significantly associated with viral load reduction/disappearance in COVID-19 patients compared to controls. Theoretically, CQ and HCQ could thus be effectively used in the treatment of SARS-CoV pneumonia. From a pharmacological standpoint, however, the major problems of oral treatment with these drugs are possible severe side effects and toxicity. Concretely, this relates to (a) the inconsistent individual bioavailability of these drugs at the alveolar target cells, depending on intestinal resorption, hepatic first-pass metabolism and accumulation in liver, spleen and lung, and (b) the need for a relatively high concentration of 1-5 µM at the alveolar surface. Therefore, we propose in a first dose estimation the use of HCQ as an aerosol in a dosage of 2-4 mg per inhalation in order to reach sufficient therapeutic levels at the alveolar epithelial cells. By using a low-dose non-systemic aerosol, adverse drug reactions will markedly be reduced compared with oral application. This increase in tolerability enables a broader use for prevention and after contact with an infected person, which would be an advantage especially for the high-risk, often multi-morbid and elderly patients. Empirical data on self-medication with a one-week aerosol application by two of the authors is presented. Inhalation was well tolerated without relevant side effects.
Mon, 6 April 2020
ARTICLE | doi:10.20944/preprints202004.0070.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: doxycycline; assay; dosage uniformity; hardness; friability; dissolution profile
Online: 6 April 2020 (15:56:54 CEST)
Persistent post market quality evaluation helps produce clear information on the current quality status of the different brands of a given drug and hence introduces biopharmaceutically and therapeutically equivalent list of the products to the prescribers and users of it. This in turn facilitates access to essential medicines by breaking the high cost barrier imposed by few expensive brands of the product. This study was aimed at determining the quality and evaluating equivalence of doxycycline hyclate capsules and tablets in Jimma, Ethiopia. Ten brands of doxycycline hyclate capsules and tablets were tested for physic-chemical parameters. All investigated brands of doxycycline complied with the USP for dosage unifor¬mity, assay of active ingredient and single-point dissolution tests. One brand, D09 failed both hardness and friabilty tests. Comparisons of dissolution profiles applying fit factors confirmed that only brands D04, D06 and D07 had similarity with innovator. Ratio test approaches also showed significant variability existence between test products and comparators. This may question the product’s being categorized as a <biowaiver> to mean in-vitro dissolution evaluation suffices its market approval. This work, however, found equivalence problems between ‘comparators’ and interchangeability issues among doxycycline different brands already distributed in the market.
Thu, 2 April 2020
HYPOTHESIS | doi:10.20944/preprints202004.0013.v1
Online: 2 April 2020 (11:06:47 CEST)
The pharmacology of azithromycin, and the actions of certain bee products, suggest the possibility of overlap with the pathophysiology of COVID-19 at several points in the disease process. First, intercellular epithelial tight junctions of the respiratory tract serve as a critical barrier to invaders. Pathophysiological factors capable of disrupting this epithelial barrier include viral virulence factors such as those observed for other coronaviruses; virulence factors derived from potentially synergistic pathogens such as Candida albicans and Porphyramonas gingivalis; and imbalances in the host inflammatory response. Azithromycin, and to a lesser extent, certain bee products, appear to have actions that oppose such processes. Second, the matrikine PGP or its derivatives may contribute to risk in individuals at high risk for serious COVID-19 infection, especially during reactivation; but azithromycin is capable of modulating PGP in some contexts. Third, the most serious COVID-19 infections are associated with massive upregulation of inflammatory cytokines such as IL-6, TNF alpha, and other inflammatory cytokines. The anti inflammatory actions of azithromycin and bee derived products such as melittin are potentially capable of modulating these processes, as well. Azithromycin is already in current use as a treatment for COVID-19; however, it's utility as a protector of epithelial barrier function would be most likely to be realized in prophylactic context rather than in a treatment context. Similarly, since the anti inflammatory effects of bee products take time, their effectiveness of melittin and other bee products would be expected to be maximized in a prophylactic context. In the context of the current pandemic, prophylaxis with azithromycin, bee products, or both, might be warranted for individuals at high risk for serious COVID-19 infection.
Wed, 1 April 2020
REVIEW | doi:10.20944/preprints202004.0007.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: nCov-19, COVID-19, coronavirus, SARS-CoV
Online: 1 April 2020 (09:30:00 CEST)
Coronaviruse disease (COVID-19) outbreak has created an emergency globally, and social distancing and isolation is the only solution to prevent its spread. Several countries have announced fully locked on to tackle this pandemic. The recent COVID-2019 has shaken the globe with incidence cases of more than half-million cases, and a mortality toll of more than twenty thousand to date. The coronavirus family is inclusive of pathogen of both – animal species and humans, encapsulating the isolated severe acute respiratory syndrome coronavirus (SARS-CoV). Researchers round the globe have been dexterously working to decode this lethal virus. Many mathematical frameworks have also been depicted which have helped to understand the dynamics of the COVID-19. Research on coronaviruses continues to explore various aspects of viral replication and pathogenesis to understanding the predilection of these viruses to switch between species, to develop an infection in a new host, and to identify significant reservoirs of coronaviruses will dramatically aid in our potential to prophesize when and where potential epidemics may occur. Many of the non-structural and accessory proteins encoded by the viruses remain unclear and unknown. This systematic review highlights the current situation of the pandemic, virus genomic composition, pathogenesis, symptomatology, diagnosis, and prognosis along with mathematical models of disease transmission and dynamics.
Tue, 31 March 2020
ARTICLE | doi:10.20944/preprints202003.0466.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; SARS-CoV-2 RBD; Ubrogepant; ACE-2; MD simulation
Online: 31 March 2020 (22:50:27 CEST)
Background: COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global pandemic affecting approximately 490,000 people and accounting for more than 22,000 deaths and has no generally acceptable cure. Here, the recently resolved 3D structure of SARS-CoV-2 receptor binding domain (RBD) in complex with its receptor-the angiotensin converting enzyme-2 (ACE-2) have provided the basis for screening chemical database for novel entry inhibitors. Methods: Molecular docking protocols have been used to rapidly screen FDA database for high affinity interaction at the SARS-CoV-2-RBD/ACE-2 interface. One of the top candidates, ubrogepant has been selected and further studied using atomistic molecular dynamics simulation method. Results: Molecular docking result showed that ubrogepant (UBR) and darunavir have binding energies of -10.4 kcal/mol. MMPBSA free energy analyses of UBR bound to RBD, ACE-2 and RBD/ACE-2 revealed RBD/ACE-2 > ACE-2 > RBD preference. Network analysis showed that interaction captured in the crystal structure were disrupted in UBR-bound state, hydration of the interface and increased atomic fluctuation within the RBD oligomerization interface and ACE-2 zinc binding site. Conclusions: The ability of ubrogepant to rupture the interaction at the RBD/ACE-2 interface residues of SARS-CoV-2 RBD/ACE-2 complex may result in loss of protein function with direct implication on oligomerization formation in RBD and loss of function in ACE-2 thus, making binding, cellular receptor recognition impossible. General Significance: Ubrogepant represents a new therapeutic candidate in the fight against COVID-19, as it binds with relatively high affinity with free RBD, ACE-2 receptor and SARS-CoV-2 RBD/ACE-2 complex based on binding affinity calculations.
ARTICLE | doi:10.20944/preprints202003.0450.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: SARS-CoV-2; COVID-19; Indian medicines; Phytotherapeutics; Favipiravir
Online: 31 March 2020 (09:56:59 CEST)
Spread of severe acute respiratory syndrome coronavirus (SARS-CoV-2) made a historic transition between December 2019 to March 2020. In the present scenario SARS-CoV-2 as becomes a major burden on public health and economic stability of societies around the globe. From the substantial evidences gained from the pandemic of SARS-CoV-2 and MERS-CoV (Middle East respiratory syndrome coronavirus), scientists and clinicians strongly believes that these pathogenic viruses share common homology of some biologically active enzymes which includes RNA-dependent RNA polymerase (RdRP), 3-chymotrypsin-like protease (3CLpro), papain-like protease (PLpro) etc. RdRP relatively grabs higher level of clinical importance in comparison with other enzyme target. Indian system of traditional medicine pioneering the therapy towards infectious disease since several centuries. In view of this potential therapeutic leads from some of the Indian medicines along with standard drug favipiravir subjected to docking investigation targeting SARS-CoV-2- RNA dependent RNA polymerase (RdRp). Residual proximity analysis reveals 18 out of 28 compounds reveals potential binding affinity of about 100% with the target amino acid residue (618 ASP, 760 ASP,761 ASP), 7 out of 28 reveals 75% binding efficacy and 3 out of 28 reveals 25% binding efficacy with that of the target residue. Hence further clinical validation may be warranted with proper in-vitro and in-vivo studies prior to the clinical recommendation in treating COVID-19 patient’s.
Sun, 29 March 2020
ARTICLE | doi:10.20944/preprints202003.0413.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: coronavirus; drug; COVID-19; SARS; MERS; ontology; ChEBI; NDF-RT; DrON; bioinformatics
Online: 29 March 2020 (01:58:40 CET)
Coronavirus-infected diseases have posed great threats to human health. In past years, highly infectious coronavirus-induced diseases, including COVID-19, SARS, and MERS, have resulted in world-wide severe infections. Our literature annotations identified 110 chemical drugs and 26 antibodies effective against at least one human coronavirus infection in vitro or in vivo. Many of these drugs inhibit viral entry to cells and viral replication inside cells or modulate host immune responses. Many antimicrobial drugs, including antimalarial (e.g., chloroquine and mefloquine) and antifungal (e.g., terconazole and rapamycin) drugs as well as antibiotics (e.g., teicoplanin and azithromycin) were associated with anti-coronavirus activity. A few drugs, including remdesivir, chloroquine, favipiravir, and tocilizumab, have already been reported to be effective against SARS-CoV-2 infection in vitro or in vivo. After mapping our identified drugs to three ontologies ChEBI, NDF-RT, and DrON, many features such as roles and mechanisms of action (MoAs) of these drugs were identified and categorized. For example, out of 57 drugs with MoA annotations in NDF-RT, 47 have MoAs of different types of inhibitors and antagonists. A total of 29 anticoronaviral drugs are anticancer drugs with the antineoplastic role. Two clustering analyses, one based on ChEBI-based semantic similarity, the other based on drug chemical similarity, were performed to cluster 110 drugs to new categories. Moreover, differences in physicochemical properties among the drugs were found between those inhibiting viral entry and viral replication. A total of 163 host genes were identified as the known targets of 68 anti-coronavirus drugs, resulting in a network of 428 interactions among these drugs and targets. Chlorpromazine, dasatinib, and anisomycin are the hubs of the drug-target network with the highest number of connected target proteins. Many enriched pathways such as calcium signaling and neuroactive ligand-receptor interaction pathways were identified. These findings may be used to facilitate drug repurposing against COVID-19.
Tue, 24 March 2020
REVIEW | doi:10.20944/preprints202003.0345.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; lysosomotropic agents; endosome; antiviral; drug repurposing
Online: 24 March 2020 (06:26:54 CET)
While the COVID-19 pandemic advances, the scientific community struggles in the search for treatments. Several improvements have been made, including the discovery of clinical efficacy of chloroquine (CQ) in COVID-19 patients, but the effective treatment protocols are still missing. In order to find novel treatment options many scientists utilize the in silico approach to identify compounds that could interfere with the key molecules involved in entrance, replication, or dissemination of the SARS-CoV-2. However, most of the identified molecules are currently not available as pharmacological agents, and assessing their safety and efficacy could take many months. Here, we took a different approach based on the proposed pharmacodynamic model of CQ in COVID-19. The main mechanism of action responsible for the favourable outcome of COVID-19 patients treated with CQ seems to be related to pH modulation-mediated effect on the endolysosomal trafficking, a characteristic of chemical compounds often called lysosomotropic agents because of the physico-chemical properties that enable them to passively diffuse through the endosomal membrane and undergo protonation-based trapping in the lumen of the acidic vesicles. In this review, we discuss lysosomotropic and lysosome targeting drugs that are already in clinical use and are characterized by good safety profiles, low cost, and wide availability. We emphasize that some of these drugs, in particular azithromycin and other macrolide antibiotics, indomethacin and some other non-steroidal anti-inflammatory drugs, proton pump inhibitors, and fluoxetine could provide additional therapeutic benefits in addition to the potential antiviral effect that still has to be confirmed by well-controlled clinical trials. As some of these drugs, mostly antibiotics, were already empirically used in the treatment of COVID-19, we encourage our colleagues all over the world to publish patient data so potential efficacy of these agents can be evaluated in the clinical context and rapidly implemented in the therapeutic protocols if the beneficial effect on clinical outcome is observed.
Mon, 23 March 2020
REVIEW | doi:10.20944/preprints202003.0345.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; lysosomotropic agents; endosome; antiviral; drug repurposing
Online: 23 March 2020 (07:28:51 CET)
While the COVID-19 pandemic advances, the scientific community struggles in the search for treatments. Several improvements have been made, including the discovery of clinical efficacy of chloroquine (CQ) in COVID-19 patients, but the effective treatment protocols are still missing. In order to find novel treatment options many scientists utilize the in silico approach to identify compounds that could interfere with the key molecules involved in entrance, replication, or dissemination of the SARS-CoV-2. However, most of the identified molecules are currently not available as pharmacological agents, and assessing their safety and efficacy could take many months. Here, we took a different approach based on the proposed pharmacodynamic model of CQ in COVID-19. The main mechanism of action responsible for the favourable outcome of COVID-19 patients treated with CQ seems to be related to pH modulation-mediated effect on the endolysosomal trafficking, a characteristic of chemical compounds often called lysosomotropic agents because of the physico-chemical properties that enable them to passively diffuse through the endosomal membrane and undergo protonation-based trapping in the lumen of the acidic vesicles. In this review, we discuss lysosomotropic drugs that are already in clinical use and are characterized by good safety profiles, low cost, and wide availability. We emphasize that some of these drugs, in particular azithromycin and other macrolide antibiotics, indomethacin and some other non-steroidal anti-inflammatory drugs, proton pump inhibitors, and fluoxetine could provide additional therapeutic benefits in addition to the potential antiviral effect that still has to be confirmed by well-controlled clinical trials. As some of these drugs, mostly antibiotics, were already empirically used in the treatment of COVID-19, we encourage our colleagues all over the world to publish patient data so potential efficacy of lysosomotropic agents can be evaluated in the clinical context and rapidly implemented in the therapeutic protocols if the beneficial effect on clinical outcome is observed.
Fri, 20 March 2020
ARTICLE | doi:10.20944/preprints202003.0302.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-2019; SARS-CoV-2; 2019-nCoV; repositioning; UPR/Autophagy; real-world evidence; pathways
Online: 20 March 2020 (03:55:55 CET)
More than 179,000 individuals have fallen ill of the Coronavirus disease (COVID-19) caused by the SARS-CoV-2 virus, which first emerged in China less than four months ago in December 2019. As of today, there exist no approved treatments against COVID-19. Vaccines are being developed, but they will take time, at least one year, to reach the population. Drug repositioning represents a fast track because already approved medicines have been broadly tested through multiple trials. We developed a repositioning strategy that mostly leads to candidates that are commonly used. The advantages are that they will facilitate proof of concept in humans through a “real-world evidence” approach and should be rapidly available to the population. We focus on the established research results that the unfolded protein response (UPR) and autophagy pathways of the host cells are essential to the life cycle of previously known coronaviruses. We performed the relevant bioinformatics analysis to understand and confirm if SARS-CoV-2 may interact with these druggable pathways. Based on these considerations, we prioritized two additional druggable pathways, which are important to the viral life cycle and tightly connected to UPR/autophagy signaling: the mitochondrial permeability transition pores (MPTP) and NLRP-3 inflammasome pathways. These four important pathways are perturbed in most major common diseases and have therefore been targeted by numerous broadly prescribed drugs. We have identified 97 approved drugs that are known to modulate these four identified pathways, and which represent, therefore, interesting repositioning candidates. Although it is indisputable that these drugs should never be used for immediate self-medication against COVID-19, we notice that some of them could also be prescribed to individuals who have COVID-19 comorbidities (e.g., hypertension). It is debated if these comorbidities are linked to the pathology itself (e.g., hypertension) or the drugs used to treat the pathology (e.g., sartans). Therefore, relevant preclinical tests and massive electronic health records (i.e., real-world evidence) must be used to pre-screen them and check the COVID-19 prognosis of individuals taking these drugs.
Tue, 17 March 2020
HYPOTHESIS | doi:10.20944/preprints202003.0279.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: chloroquine; COVID-19; SARS-CoV2; antiviral; viral prophylaxis
Online: 17 March 2020 (15:57:38 CET)
The novel coronavirus 2019 (COVID-19) pandemic is rapidly advancing despite public health measures. Pharmaceutical prophylaxis is an established approach to potentially control infectious diseases and is one solution to the urgent public health challenge posed by COVID-19. Screening and development of new vaccines and antivirals is expensive and time consuming while the repositioning of available drugs should receive priority attention as well as international government and agency support. Here we propose an old drug chloroquine (CQ) to be urgently repositioned as an ideal antiviral prophylactic against COVID-19. CQ has ability to block viral attachment and entry to host cells. Its proven clinical efficacy against a variety of viruses including COVID-19 and its current deployment in COVID-19 therapeutic trials strengthens its potential candidacy as a prophylactic. Furthermore, CQ has a long safety record, is inexpensive and widely available. Here we reviewed CQ's antiviral mechanisms, its laboratory efficacy activity against COVID-19, as well as CQ's pharmacokinetics in its established use against malaria and autoimmune diseases to recommend safe and potentially efficacious dose regimens for protection against COVID-19: a pre-exposure prophylaxis of 250-500mg daily and post-exposure prophylaxis at 8mg/kg/day for 3 days. We recommend further urgent research on CQ for COVID-19 prevention and urge that the above regimens be investigated in parallel with mass deployment by relevant agencies in attempts to contain the pandemic without unnecessary regulatory delays as benefits far outweigh risks or costs.
Sun, 15 March 2020
ARTICLE | doi:10.20944/preprints202003.0246.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: coronavirus; COVID-19; disease severity; transmission route; infection route; lung damages; cold flu influenza
Online: 15 March 2020 (14:39:19 CET)
In the war against the COVID-19 pandemic, the world is experiencing severe resource constraints. Although transmission routes are well understood, we suspect that they cause different disease consequences. We evaluate them in different forms to understand how they affect infection rates and disease severity. In determining how they affect disease outcome, we evaluated target tissue vulnerability, functional role, defense mechanisms, viral concentration, infection vicinity to target vital tissue, and host factors. We found that direct lung infection is the most lethal transmission route followed by bronchi infection. Transmissions by physical contacts, foods, and blood by low viral concentration (as expected in normal human activities) pose lower or much lower risks unless the infection is followed by subsequent lung exposures. After adding transmission route, treatment timings, and improper treatments into the list of known risk factors, we found that death rate and disability rate for young or healthy persons are nearly zero. We show that population based medical model improperly shifts nominal death rate from few vulnerable people to the population resulting in unnecessary population panic, and such panic is responsible for shutting down human activities and the world economy. Finally, we examined limitations in population-based mitigating measures and proposed for governmental and private adoption community guidelines, which are mainly to enable vulnerable people avoid exposures, prevent non-vulnerable people from serving as viral transmitters, get rid of high-risk exposure modes in working environment, improve safety for people in buses, ships and planes, and reduce death and disability rates for infected people.
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; SARS-CoV-2; 3CLpro; PLpro; RdRp; AAK1; inhibitor; dock; molecular dynamics
Online: 15 March 2020 (02:34:14 CET)
The current outbreak of coronavirus disease (COVID-19) caused by SARS-CoV-2 in Wuhan, China has killed more than 2600 people since December 2019. Currently there is no effective treatment for this epidemic. Drug for anti SARS-CoV-2 are urgently needed. In this study we evaluated two compound libraries containing launched drugs and compounds from 300 kinds of Traditional Chinese Medicine in order to find anti SARS-CoV-2 drugs. Docking and then calculating binding free energy were performed as workflow against four key anti-SARS-CoV-2 drug targets, 3CLpro, PLpro and RdRp from SARSCoV-2, and AAK1 from human as well. As a result, drugs launched with potential for antiviral usage were selected in the hope of providing some knowledge for future drug discovery.
Fri, 13 March 2020
ARTICLE | doi:10.20944/preprints202003.0226.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-2019; Mpro; 6LU7; medicinal plant compounds; docking
Online: 13 March 2020 (03:19:02 CET)
COVID-19, a new strain of coronavirus (CoV), was identified in Wuhan, China, in 2019. No specific therapies are available and investigations regarding COVID-19 treatment are lacking. Liu et al. (2020) successfully crystallised the COVID-19 main protease (Mpro), which is a potential drug target. The present study aimed to assess bioactive compounds found in medicinal plants as potential COVID-19 Mpro inhibitors, using a molecular docking study. Molecular docking was performed using Autodock 4.2, with the Lamarckian Genetic Algorithm, to analyse the probability of docking. COVID-19 Mpro was docked with several compounds, and docking was analysed by Autodock 4.2, Pymol version 18.104.22.168 Edu, and Biovia Discovery Studio 4.5. Nelfinavir and lopinavir were used as standards for comparison. The binding energies obtained from the docking of 6LU7 with native ligand, nelfinavir, lopinavir, kaempferol, quercetin, luteolin-7-glucoside, demethoxycurcumin, naringenin, apigenin-7-glucoside, oleuropein, curcumin, catechin, epicatechin-gallate, zingerol, gingerol, and allicin were -8.37, -10.72, -9.41, -8.58, -8.47, -8.17, -7.99, -7.89, -7.83, -7.31, -7.05, -7.24, -6.67, -5.40, -5.38, and -4.03 kcal/mol, respectively. Therefore, nelfinavir and lopinavir may represent potential treatment options, and kaempferol, quercetin, luteolin-7-glucoside, demethoxycurcumin, naringenin, apigenin-7-glucoside, oleuropein, curcumin, catechin, and epicatechin-gallate appeared to have the best potential to act as COVID-19 Mpro inhibitors. However, further research is necessary to investigate their potential medicinal use.
Thu, 12 March 2020
ARTICLE | doi:10.20944/preprints202003.0214.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: SARS-Cov-2; Citrus sp.; Galangal; Curcuma sp.; Sappan wood
Online: 12 March 2020 (13:59:40 CET)
COVID-19 pandemic is a serious problem in the world today. The SARS-CoV-2 virus that causes COVID-19 has important proteins used for its infection and development, namely the protease and spike glycoprotein. The RBD (Receptor Binding Domain) of spike glycoprotein (RBD-S) can bind to the ACE2 (Angiotensin Converting Enzyme-2) receptor at the protease domain (PD) (PD-ACE2) of the host cell, thereby leading to a viral infection. This study aims to reveal the potential of compounds contained in Curcuma sp., Citrus sp., Alpinia galanga, and Caesalpinia sappan as anti SARS-CoV-2 through its binding to 3 protein receptors. The study was conducted by molecular docking using the MOE 2010 program (licensed from Faculty of Pharmacy UGM, Indonesia). The selected protein targets are RBD-S (PDB ID:6LXT), PD-ACE2 (PDB ID: 6VW1), and SARS-CoV-2 protease (PDB ID:6LU7). The affinities of bonds formed is represented as a docking score. The results show that hesperidin, one of the compounds in Citrus sp., has the lowest docking score for all three protein receptors representing the highest affinity to bind the receptors. Moreover, all of the citrus flavonoids possess good affinity to the respected receptors as well as curcumin, brazilin, and galangin, indicating that those compounds perform inhibitory potential for the viral infection and replication. In general, the results of this study indicate that Citrus sp. exhibit the best potential as an inhibitor to the development of the SARS-CoV-2, followed by galangal, sappan wood, and Curcuma sp. that can be consumed in daily life as prophylaxis of COVID-19.
Wed, 11 March 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: metabolic functionalization of alkyl moieties in drug molecules; structure influence on metabolic functionalization of alkyl moieties; mechanism of alkyl free radical hydroxy functionalization; pharmacologic activity of hydroxy and carboxy functionalized alkyl moieties in drug molecules; primary and auxiliary pharmacophores; auxophores
Online: 11 March 2020 (03:20:58 CET)
Alkyl moieties—open chain or cyclic—are common in drug molecules and can be internal or terminal. The open-chain alkyls can be linear or branched; the cyclic alkyls may be substituted. Usually, the branches in open-chain alkyls and substituents in cycloalkyls influence both the pharmacokinetics and pharmacodynamics of a drug molecule. The hydrophobicity of alkyl moieties in drug molecules is modified by metabolic hydroxy functionalization via free-radical intermediates to give primary, secondary, or tertiary alcohols depending on the class of the substrate carbon. The hydroxymethyl groups resulting from the functionalization of methyl groups are mostly oxidized further to carboxyl groups to give carboxy metabolites. As observed from the surveyed cases in this review, hydroxy functionalization leads to loss, attenuation, or retention of pharmacologic activity with respect to the parent drug. On the other hand, carboxy functionalization leads to a loss of activity with the exception of only a few cases in which activity is retained. The exceptions are those groups in which the carboxy functionalization occurs at a position distant from a well-defined primary pharmacophore. Some parent-drug equiactive hydroxy metabolites have been developed into metabolite ester prodrugs, while some of the parent-drug carboxy metabolites have been developed into metabolite drugs. In this review, we present and discuss the above state of affairs for a variety of drug classes, using selected drug members to show the effect on pharmacologic activity as well as dependence of the metabolic change on drug molecular structure. Some subtexts found to manifest from the hydroxy and carboxy functionalization of alkyl moieties in drug molecules are presented and discussed. The review provides basis for informed predictions of (i) structural features required for metabolic hydroxy and carboxy functionalization of alkyl moieties in existing or planned small drug molecules; and (ii) whether the resulting metabolites will possess pharmacologic activity or be devoid of it.
Tue, 10 March 2020
ARTICLE | doi:10.20944/preprints202003.0153.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: unrecorded alcohol; home-produced fruit spirits; metals; lead; cadmium; ethanol; health risk; risk assessment; margin of exposure
Online: 10 March 2020 (02:44:16 CET)
Unrecorded alcohol comprises all types of alcohol that is not registered in the jurisdiction where it is consumed. In some countries in Central and Eastern parts of Europe as well as the Balkan, the major amount of unrecorded alcohol consumption may derive from homeproduction of fruit spirits. Some studies found a high prevalence of lead and cadmium in such spirits. This article provides a quantitative comparative risk assessment using the margin of exposure (MOE) methodology for lead and cadmium, compared to ethanol, for unrecorded fruit spirits. For average concentration levels, the lowest MOE (0.8) was calculated for ethanol (alcohol itself). For lead, the MOE was 13 for moderate daily drinking and 0.9 for the worst case. For cadmium, the MOE was 1982 for moderate daily drinking and 113 for the worst case. The results of this study are consistent with previous comparative risk assessments that ethanol itself comprises by far the highest risk of all compounds in alcoholic beverages. Regarding the metal contaminants, the risk of cadmium appears negligible, however, lead may pose an additional health risk in heavy drinking circumstances. Strategies to avoid metal contamination in settings of artisanal homeproduction of spirits need to be developed.
Mon, 9 March 2020
COMMUNICATION | doi:10.20944/preprints202002.0418.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: virtual screening; molecular docking; drug repurposing; drug repositioning; anti-viral drugs; Coronavirus; COVID-19; 2019-nCoV; SARS-CoV-2
Online: 9 March 2020 (02:29:04 CET)
SARS-CoV-2 is the betacoronavirus responsible for the COVID-19 pandemic. It was listed as a potential global health threat by WHO due to high mortality, high basic reproduction number and lack of clinically approved drugs and vaccines for COVID-19. The genomic sequence of the virus responsible for COVID-19, as well as the experimentally determined three dimensional structure of the Main protease (Mpro) are available. The reported structure of the target Mpro was utilized in this study to identify potential drugs for COVID-19 using molecular docking based virtual screening of all approved drugs. The results of this study confirm preliminary reports that some of the drugs approved for treatment of other viral infections have the potential for treatment of COVID-19. Selected antiviral drugs, approved for human therapeutic applications, were ranked for potential effectiveness against COVID-19, based on predicted binding energy to the target Mpro of SARS-CoV-2, and novel candidates for drug repurposing were identified in this study. In addition, potential mechanisms for beneficial off target effects of some drugs in clinical trials were identified by using molecular docking.
Sat, 29 February 2020
BRIEF REPORT | doi:10.20944/preprints202002.0242.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; molecular docking; HIV protease inhibitor; nucleotide analogues
Online: 29 February 2020 (12:43:40 CET)
The outbreak of novel coronavirus (COVID-19) infections in 2019 is in dire need of finding potential therapeutic agents. In this study, we used molecular docking to repurpose HIV protease inhibitors and nucleoside analogues for COVID-19, with evaluations based on docking scores calculated by AutoDock Vina and RosettaCommons. Our results suggest that Indinavir and Remdesivir possess the best docking scores, and comparison of the docking sites of the two drugs reveal a near perfect dock in the overlapping region of the protein pockets. After further investigation of the functional regions inferred from the proteins of SARS coronavirus, we discovered that Indinavir does not dock on any active sites of the protease, which may give rise to concern in regards to the efficacy of Indinavir. On the other hand, the docking site of Remdesivir is not compatible with any known functional regions, including template binding motifs, polymerization motifs and nucleoside triphosphate (NTP) binding motifs. However, when we tested the active form (CHEMBL2016761) of Remdesivir, the docking site revealed a perfect dock in the overlapping region of the NTP binding motif. This result suggests that Remdesivir could be a potential therapeutic agent. Clinical trials still must be done in order to confirm the curative effect of these drugs.
Fri, 28 February 2020
COMMUNICATION | doi:10.20944/preprints202002.0418.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: virtual HTS; docking; drug reposition; drug repurposing; coronavirus; COVID-19; 2019-nCoV; SARS-CoV-2
Online: 28 February 2020 (02:38:05 CET)
SARS-CoV-2 is a betacoronavirus that was first identified during the Wuhan COVID-19 epidemic in 2019. It was listed as a potential global health threat by WHO due to high mortality, high basic reproduction number and lack of clinically approved drugs and vaccines for COVID-19. The genomic sequence of the virus responsible for COVID-19, as well as the experimentally determined three dimensional structure of the Main protease (Mpro) are available. The reported structure of the target Mpro was utilized in this study to identify potential drugs for COVID-19 using virtual high throughput screening. The results of this study confirm earlier preliminary reports based on studies of homologs that some of the drugs approved for treatment of other viral infections also have the potential for treatment of COVID-19. Approved anti-viral drugs that target proteases were ranked for potential effectiveness against COVID-19 and novel candidates for drug repurposing were identified.
Sun, 23 February 2020
ARTICLE | doi:10.20944/preprints202002.0308.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: SARS-CoV-2; COVID-19; 3CL protease; molecular docking; molecular dynamics and simulations
Online: 23 February 2020 (02:17:46 CET)
The SARS-CoV-2 was confirmed to cause the regional outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China. The 3C-like protease (3CLpro), an essential enzyme for viral replication, is a valid target to compacts SARS-CoV and MERS-CoV. In this research, an integrated library consisting of 1000 compounds from Asinex Focused Covalent (AFCL) library and 16 FDA-approved protease inhibitors were screened against SARS-CoV-2 3CLpro. Top compounds with significant docking scores and making stable interactions with catalytic dyad residues were obtained. The screening results in identification of compound 621 from AFCL library as well as Paritaprevir and Simeprevir from FDA-approved protease inhibitors as potential inhibitors of SARS-CoV-2 3CLpro. The mechanism and dynamic stability of binding between the identified compounds and SARS-CoV-2 3CLpro were characterized using 50 nanoseconds (ns) molecular dynamic (MD) simulation approach. The identified compounds are potential inhibitors worthy of further development as SARS-CoV-2 3CLpro inhibitors/drugs. Importantly, the identified FDA-approved therapeutics could be ready for clinical trials to treat infected patients and help to curb the COVID-19.
Tue, 18 February 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: essential fatty acid semi carbazide; ID50; IL-4; IL-12
Online: 18 February 2020 (11:15:32 CET)
Bacterial infections are world-wide problem and resistant bacteria is increasing globally that lead to treatments failure. Thus, it is important to find new techniques that are effective for the treatment antibiotic-resistant microorganisms. Green medicine used for the medication of different bacterial infection. Therefore , the study aimed to evaluate the immunomodulatory activity of essential fatty acid semi carbazide (EFASC) compounds extracted from flaxseed to eradicate resistance pathogens . Crud extracts of Linum usitatissimum was extracted by hexane for extraction of EFASC. The results of LD50 appear that a live suspension of E.coli was 0.49×107 ,while HK E.coli was 108 , 125 mg /ml were the optimum dose in stimulate immune response of EFASC which gave maximum dose of total WBC , Neutrophil and Monocyte count. The immunomodulatory activity appear that E.coli + EFASC released moderate levels of IL-4 . HK E.coli release higher IL-4 lead to increase the hypersensitivity and hyper responses of immune system. HK + EFASC immunogen revealed moderate increased in IL-12 mean level 0.99 pg /ml, HK bacteria recorded 1.49 pg/ml, while the mean of EFASC revealed no significant different compare with control. An effective protection was observed in immunized groups with HK E.coli and EFASC challenged with 100 of LD50 of a live E.coli.
Mon, 17 February 2020
BRIEF REPORT | doi:10.20944/preprints202002.0242.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: COVID-19; molecular docking; HIV protease inhibitor; nucleotide analogues
Online: 17 February 2020 (07:28:31 CET)
The outbreak of novel coronavirus (COVID-19) infections occurring in 2019 is in dire need of finding potential therapeutic agents. In this study, we used molecular docking strategies to repurpose HIV protease inhibitors and nucleotide analogues for COVID-19. The evaluation was made on docking scores calculated by AutoDock Vina and RosettaCommons. Preliminary results suggested that Indinavir and Remdesivir have the best docking scores and the comparison of the docking sites of these two drugs shows a near perfect dock in the overlap region of the protein pocket. However, the active sites inferred from the proteins of SARS coronavirus are not compatible with the docking site of COVID-19, which may give rise to concern in the efficacy of drugs.
Sat, 15 February 2020
ARTICLE | doi:10.20944/preprints202002.0205.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Pyracantha angustifolia; p-Hydroxybenzoic acid beta-D-glucosylester; Cimidahurinine; melanin; tyrosinase; antioxidant
Online: 15 February 2020 (15:21:13 CET)
Pyracantha angustifolia has been used in traditional medicine to treat a range of diseases of the stomach and improve digestion, blood circulation, diarrhea, dysentery, and hemostasis. This study evaluated bioactivity-guided fractionation as a means to identify therapeutic phytochemicals from P. angustifolia that can attenuate melanogenesis and oxidation. Seven compounds with inhibitory effects on melanin production and tyrosinase (TYR) activity, as well as ABTS and DPPH radical scavenging activities, and have not been reported as whitening materials, were isolated from the n-butanol fraction from P. angustifolia leaves (PAL). Among the seven compounds, p-hydroxybenzoic acid beta-d-glucosylester (HG), and cimidahurinine (CD) had strong inhibitory effects of melanin production, TYR activity, and ABTS and DPPH radical scavenging activities. Western blot analysis showed that HG and CD suppressed tyrosinase-related protein (TYRP)-1 and TYRP-2 expression. These results suggest that P. angustifolia containing active compounds, such as HG and CH, is a potent therapeutic candidate for the development of hypopigmenting agents.
Fri, 14 February 2020
ARTICLE | doi:10.20944/preprints202002.0178.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: DILIrank; DILI; drug hepatotoxicity; QSAR; nested cross-validation; virtual screening; in silico
Online: 14 February 2020 (02:24:04 CET)
Drug induced liver injury (DILI) remains one of the challenges in the safety profile of both authorized drugs and candidate drugs and predicting hepatotoxicity from the chemical structure of a substance remains a challenge worth pursuing, being also coherent with the current tendency for replacing non-clinical tests with in vitro or in silico alternatives. In 2016 a group of researchers from FDA published an improved annotated list of drugs with respect to their DILI risk, constituting “the largest reference drug list ranked by the risk for developing drug-induced liver injury in humans”, DILIrank. This paper is one of the few attempting to predict liver toxicity using the DILIrank dataset. Molecular descriptors were computed with the Dragon 7.0 software, and a variety of feature selection and machine learning algorithms were implemented in the R computing environment. Nested (double) cross-validation was used to externally validate the models selected. A number of 78 models with reasonable performance have been selected and stacked through several approaches, including the building of multiple meta-models. The performance of the stacked models was slightly superior to other models published. The models were applied in a virtual screening exercise on over 100,000 compounds from the ZINC database and about 20% of them were predicted to be non-hepatotoxic.
Tue, 11 February 2020
ARTICLE | doi:10.20944/preprints202002.0139.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: restricticin; marine fungus; Penicillium janthinellum; BV-2 microglia cells; anti-inflammatory; rotamer
Online: 11 February 2020 (09:28:35 CET)
A new compound containing a triene, a tetrahydropyran ring and glycine ester functionalities, restricticin B (1), together with four known compounds (2-5) were obtained from the EtOAc extract of the marine fungus Penicillium janthinellum. The planar structure of 1 was determined by detailed analyses of MS, 1D and 2D NMR data. The relative and absolute configurations of 1 were established via analyses of NOESY spectroscopy data, comparison of optical rotation values with those of restricticin derivatives reported and electronic circular dichroism (ECD). All the compounds were screened for their anti-neuroinflammatory effects in lipopolysaccharide (LPS)-induced BV-2 microglia cells. Restricticin B (1) and N-acetyl restricticin (2) exhibited anti-neuroinflammatory effects by suppressing the production of pro-inflammatory mediators in activated microglial cells.
Tue, 4 February 2020
ARTICLE | doi:10.20944/preprints202002.0047.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: 2019-nCoV; therapeutic strategies; drug; ACE2
Online: 4 February 2020 (10:59:25 CET)
Most recently, an outbreak of severe pneumonia caused by the infection of 2019-nCoV, a novel coronavirus first identified in Wuhan, China, imposes serious threats to public health. Many important aspects about 2019-nCoV remain largely unknown, among which, the limitation of antiviral therapies represents one of the most critical problems. More recently, it was confirmed that human ACE2 is the receptor for the entry of 2019-nCoV into lower respiratory tract epithelial cells. Give this observation, it is thus expected that the virus could be inhibited if we decrease the expression of ACE2. Here by screening two databases, Connectivity Map (CMap) and our JeaMoon Map (JMap), we identified a number of candidate agents that decrease ACE2 expression. CMap analysis identified 5 compounds, among which, Azathioprine is a possible therapeutic strategy for anti-2019-nCoV. Moreover, JMap analysis revealed a number of comounds, biologics, and traditional Chinese medicine, among which, Andrographis, Urtica, Sambucus, Astragalus, valproic acid, butyrate, and epoxomicin represent the most significant and possible strategies for anti-2019-nCoV therapies. This study provides a number of clues and possible therapeutic strategies for 2019-nCoV prevention and treatment.
ARTICLE | doi:10.20944/preprints202002.0041.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: geranylgeranyl acetone (GGA); heat shock proteins (Hsps); HT-22 (hippocampal neuronal) cells; mitochondrial membrane potentials
Online: 4 February 2020 (10:24:57 CET)
Geranylgeranyl acetone (GGA) protects against various types of cell damages by upregulating heat shock proteins. We investigated whether GGA protect neuronal cells from cell death induced by oxidative stress. Glutamate exposure was lethal to HT-22 cells which comprise a neuronal line derived from mouse hippocampus. This configuration is often used as a model for hippocampus neurodegeneration in vitro. In the present study, GGA protected HT-22 cells from glutamate-induced oxidative stress. GGA pretreatment did not induce Hsps. Moreover, reactive oxygen species increased to the same extent in both GGA-pretreated and untreated cells exposed to glutamate. In contrast, glutamate exposure and GGA pretreatment increased mitochondrial membrane potential. However, increases in intracellular Ca2+ concentration were inhibited by GGA pretreatment. In addition, the increase of phosphorylated ERKs by the glutamate exposure was inhibited by GGA pretreatment. These findings suggest that GGA protects HT-22 cells from glutamate-provoked cell death without Hsp induction and that the mitochondrial calcium buffering capacity plays an important role in this protective effect.
Mon, 3 February 2020
ARTICLE | doi:10.20944/preprints202002.0003.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: drug repositioning/repurposing; dopamine transporter (DAT); benztropine; tumoroids; signal transducer and activator of transcription (STAT); circulating tumor cells (CTC); three-dimensional (3D) culture
Online: 3 February 2020 (03:16:54 CET)
Tumor growth, progression, and therapy resistance are crucial factors in the prognosis of cancer. Properties of three-dimensional tumor-like organoids (tumoroids) more closely resemble in vivo tumors compared to two-dimensionally cultured cells and are therefore effectively used for assays and drug screening. We here established a repurposed drug for novel anticancer research and therapeutics using a tumoroid-based screening system. We screened 6 pharmacologically active compounds by using an original tumoroid-based multiplex phenotypic screening system with matrix metalloproteinase 9 (MMP9) promoter-driven fluorescence reporter for the evaluation of both tumoroid formation and progression. The effects of one of the hit compounds were examined on tumor formation and progression in vitro and in vivo. Antiparkinson drug benztropine was the most effective compound uncovered by the screen. Benztropine significantly inhibited in vitro tumoroid formation, cancer cell survival, and MMP9 promoter activity. Benztropine also reduced the activity of oncogenic signaling transducers and trans-activators for MMP9, including STAT3, NF-κB, and β-catenin, and properties of cancer stem cells / cancer-initiating cells. Benztropine and GBR-12935 directly targeted the dopamine transporter DAT/SLC6A3, whose genetic alterations such as amplification were correlated with poor prognosis for cancer patients. Benztropine also inhibited tumor growth, circulating tumor cell (CTC) number, and rate of metastasis in a tumor allograft model in mice. In conclusion, we propose the repurposing of benztropine for anticancer research and therapeutics that can suppress tumor progression, CTC, and metastasis of aggressive cancers by reducing key pro-tumorigenic factors.
Sat, 18 January 2020
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: acetylcholine; muscarinic receptors; allosteric modulation
Online: 18 January 2020 (10:25:54 CET)
Allosteric modulators are ligands that bind to a site on the receptor that is spatially separated from the orthosteric binding site for the endogenous neurotransmitter. Allosteric modulators modulate the binding affinity, potency and efficacy of orthosteric ligands. Muscarinic acetylcholine receptors are prototypical allosterically-modulated G-protein-coupled receptors. They are a potential therapeutic target for the treatment of psychiatric, neurologic and internal diseases like schizophrenia, Alzheimer’s disease, Huntington disease, type 2 diabetes or chronic pulmonary obstruction. Here we review progress made during the last decade in our understanding of their mechanisms of binding, allosteric modulation and in vivo actions of in order to understand the translational impact of studying this important class of pharmacological agents. We overview newly developed allosteric modulators of muscarinic receptors as well as new spin-off ideas like bitopic ligands combining allosteric and orthosteric moieties and photo-switchable ligands based on bitopic agents.
Sat, 11 January 2020
ARTICLE | doi:10.20944/preprints202001.0110.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: oxidative stress; reactive oxygen species; hypoxia-reoxygenation; GluN2B; CNS neuron; Gelidium amansii
Online: 11 January 2020 (14:05:37 CET)
Oxidative stress is known to be critically implicated in the pathophysiology of several neurological disorders, including Alzheimer’s disease and ischemic stroke. The remarkable neurotrophic activity of Gelidium amansii, has been reported consistently in a series of our previous studies, inspired us to investigate whether this popular agarophyte could protect against hypoxia/reoxygenation (H/R)-induced oxidative injury in hippocampal neurons. The primary culture of hippocampal neurons challenged with H/R suffered from a significant loss of cell survival, accompanied by apoptosis and necrosis, DNA damage, generation of reactive oxygen species (ROS), and dissipation of mitochondrial membrane potential (MMP) which were successfully attenuated when the neuronal cultures were preconditioned with GAE, an optimized ethanolic extract of G. amansii. Moreover, the expression of N-methyl-D-acetate receptor subunit 2B (GluN2B), an extrasynaptic glutamate receptor, was significantly repressed in GAE-treated neurons as compared to those without GAE intervention. Together, this study demonstrates that GAE attenuated H/R-induced oxidative injury in hippocampal neurons through, at least in part, a potential neuroprotective mechanism that involves inhibition of GluN2B-mediated excitotoxicity and suppression of ROS production, and suggest that this edible seaweed could be a potential source of bioactive metabolites having therapeutic significance against oxidative stress-related neurodegeneration, including ischemic stroke and neurodegenerative diseases.
ARTICLE | doi:10.20944/preprints202001.0109.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Alzheimer’s disease; curcumin; network pharmacology; molecular simulation; neurodegeneration; TrkB/PI3K signaling; autophagy
Online: 11 January 2020 (13:53:12 CET)
Curcumin is one of the bioactive metabolites of turmeric (Curcuma longa), known for its pleiotropic pharmacological actions, including antioxidant and anti-inflammation, anticholinesterase, immunomodulation, and neuroprotection. Substantial evidence suggests the therapeutic benefits of curcumin against neurodegenerative disorders, including Alzheimer’s disease (AD), acting on a diverse array of brain targets that make the molecular mechanisms complicated. System biology level-investigation could potentially present a comprehensive molecular mechanism to delineate the neuropharmacological action of curcumin. In this study, we used integrated system pharmacology and molecular simulation analysis to gain insights into the underlying mechanism of curcumin action against AD. Network pharmacology study identified curcumin-targeted potential cellular pathways such as phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling, neurotrophin signaling, toll-like receptor (TLR) signaling, and autophagy, and proteins such as tropomyosin receptor kinase B (TrkB), liver X-receptor-beta (LXR-β), estrogen receptor-β (ER-β), mammalian target of rapamycin (mTOR), TLR-2, N-methyl-D-acetate receptor subunit 2B (GluN2B), β-secretase and glycogen synthase kinase-3β (GSK-3β), which are intimately associated with neuronal growth and survival, immune response, and inflammation. Moreover, the molecular modeling further verified that curcumin showed a significant binding affinity to mTOR, TrkB, LXR-β, TLR-2, ER-β, GluN2B, β-secretase, and GSK-3β, which are the crucial regulators of molecular and cellular processes associated with AD. Together, the present system pharmacology and in silico findings demonstrate that curcumin might play a significant role in modulating AD-pathobiology, supporting its therapeutic application for the prevention and treatment of AD.
Sun, 29 December 2019
REVIEW | doi:10.20944/preprints201912.0386.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: resistance-associated secretory phenotype (RASP); extracellular vesicle (EV); exosome; oncosome; drug resistance; epithelial-mesenchymal transition (EMT); heat shock protein (HSP); cell stress response; hypoxia; acidosis; tumor immunology
Online: 29 December 2019 (13:46:21 CET)
Extracellular vesicles (EVs), such as exosomes or oncosomes are released with molecules unfavorable for survival from cells. In addition, accumulating evidence has shown that tumor cells often eject anti-cancer drugs such as chemotherapeutics and targeted drugs within EVs, a novel mechanism of drug resistance. The EV-releasing, drug resistance phenotype is often coupled with cellular dedifferentiation and transformation, cells undergoing epithelial-mesenchymal transition (EMT) and taking on a cancer stem cell phenotype. Recent studies have shown that the release of EVs is also involved in immunosuppression. The concept of the resistance-associated secretory phenotype (RASP) is reviewed herein.
Thu, 5 December 2019
ARTICLE | doi:10.20944/preprints201912.0058.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: mitochondrial dysfunction; idebenone; short-chain quinone; metabolic stability; HepG2 cell culture; reverse-phase liquid chromatography
Online: 5 December 2019 (03:56:02 CET)
Short chain quinones (SCQs) have been identified as potential drug candidates against mitochondrial dysfunction, which is largely dependent on their reversible redox characteristics of the active quinone core. We recently synthesized a SCQ library of > 148 naphthoquinone derivatives and identified 16 compounds with enhanced cytoprotection compared to the clinically used benzoquinone idebenone. One of the major drawbacks of idebenone is its high metabolic conversion in the liver, which significantly restricts is therapeutic activity. Therefore, this study assessed the metabolic stability of the 16 identified naphthoquinone derivatives 1-16 using hepatocarcinoma cells in combination with an optimized reverse-phase liquid chromatography (RP-LC) method. Most of the derivatives showed significantly better stability than idebenone over 6 hours (p < 0.001). By extending the side-chain of SCQs, increased stability for some compounds was observed. Metabolic conversion from the derivative 3 to 5 and reduced idebenone metabolism in the presence of 5 were also observed. These results highlight the therapeutic potential of naphthoquinone-based SCQs and provide essential insights for future drug design, prodrug therapy and polytherapy, respectively.
Wed, 20 November 2019
ARTICLE | doi:10.20944/preprints201911.0244.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: activated inflammatory macrophages; quercetin; pro-/anti-inflammatory cytokine genes; STAT3 protein phosphorylation; TLR2
Online: 20 November 2019 (16:04:42 CET)
Our previous studies demonstrated that quercetin (Q) could be ingested and metabolized by macrophages and exerted prophylactic immuno-stimulatory activity and therapeutic anti-inflammatory effects on lipopolysaccharide (LPS)-treated macrophages ex vivo. To further clarify its possible anti-inflammatory mechanism, Q was selected to treat mouse peritoneal macrophages that obtained from female BALB/c mice exposed to LPS i.p. for 12 h. Relative gene expression of pro-/anti-inflammatory (TNF-α/IL-10) cytokines and components of inflammation-related intracellular signaling pathways (TLR2, TLR4, NF-κB, JAK2 and STAT3) was analyzed using two-step reverse transcription (RT) and real-time quantitative polymerase chain reaction (qPCR). STAT3 protein phosphorylation was determined using an in-cell ELISA method. As a result, Q and its metabolite quercetin-3-O-β-D-glucuronide (Q3G) decreased TNF-α gene expression amounts and ratios of pro-/anti-inflammatory (TNF-α/IL-10) cytokine gene expressions, but increased IL-10 gene expression amounts in activated inflammatory macrophages, supporting a substantial anti-inflammatory potential of Q and Q3G treatments. However, Q3G had lower effects than those of Q. Importantly, Q inhibited TLR2 gene expression and phosphorylation of STAT3 protein in the inflamed cells. Our results are the first report to suggest that Q inhibits LPS-induced inflammation ex vivo through suppressing TLR2 gene expression and STAT3 protein phosphorylation in activated inflammatory macrophages. Q has potential to further apply for treating inflammation-associated diseases.
ARTICLE | doi:10.20944/preprints201911.0239.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: edible marine alga; anticancer; hizikia fusiformis; saringosterol acetate; apoptosis
Online: 20 November 2019 (11:19:19 CET)
Hizikia fusiformis is a common, edible marine alga found in Asia. Although the anticancer activity of its extracts has previously been investigated, its active compounds have not been identified. In this study, saringosterol acetate (SA) was isolated from H. fusiformis extracts by centrifugal partition chromatography (CPC) system (two phase solvents condition: n-hexane:ethyl acetate/methanol:water = 5:3:7:1, v/v), exhibited anticancer effects in the human lung adenocarcinoma epithelial cell line, A549, by inducing apoptosis and sub-G1 phase cell cycle arrest. In addition, SA increased the expression of the pro-apoptotic proteins, Bax and cleaved caspase 3, and decreased that of the anti-apoptotic protein Bcl-xL. Although, SA did not affect the expression of p53, induces expression of Bid and caspase 8. In conclusion, we suggested that SA induces apoptosis against A549 cells via Bid and caspase 8 dependent pathway.
Sun, 17 November 2019
ARTICLE | doi:10.20944/preprints201911.0206.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: leukemia; relapse; quiescence; dormancy; curcumin derivative; Hsp90; apoptosis; protein aggregation
Online: 17 November 2019 (14:06:46 CET)
Relapsed leukemia following initial therapeutic response and remission is difficult to treat and causes high patient mortality. Leukemia relapse is due to residual quiescent leukemia cells that escape conventional therapies and later reemerge. Eliminating not only growing but quiescent leukemia cells is critical to effectively treating leukemia and preventing its recurrence. Such therapeutic agents, however, are lacking in the clinic. Here we report that a 4-arylmethyl derivative of the natural anticancer compound curcumin demonstrates a dual effect in eliminating both growing and quiescent leukemia cells. This curcumin derivative, C212, on the one hand, inhibits growing leukemia cells at a higher efficacy than curcumin by inducing apoptosis and cell cycle arrest; it, on the other hand, kills quiescent leukemia cells that are resistant to conventional chemotherapy drugs. Furthermore, C212 drives leukemia cells into and kills them at deep quiescence, avoiding the potential risk associated with awaking therapy-resistant subpopulation of quiescent leukemia cells. Lastly, we show that C212 induces apoptosis and drives cells into deep dormancy at least partially by binding to and inhibiting Hsp90, leading to client protein degradation and protein aggregation. Further elucidating the molecular mechanisms underlying the dual function of C212 in eliminating both growing and quiescent leukemia cells will aid the development of novel therapies against leukemia relapse.
Thu, 31 October 2019
REVIEW | doi:10.20944/preprints201910.0365.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: pharmacological chaperones; mucopolysaccharidoses; mps; small molecules
Online: 31 October 2019 (09:33:43 CET)
The mucopolysaccharidoses (MPS) are a group of 11 lysosomal storage diseases (LSDs) produced by mutations in the enzymes involved in the lysosomal catabolism of glycosaminoglycans. Most of the mutations affecting these enzymes may lead to changes in processing, folding, glycosylation, pH stability, protein aggregation, and defective transport to the lysosomes. The use of small molecules, called pharmacological chaperones (PCs), that can restore the folding, trafficking and biological activity of mutated enzymes has been extensively explored in LSDs as a therapeutic alternative. PCs have the advantage of wide tissue distribution, potential oral administration, lower production cost, and fewer issues of immunogenicity. In this paper, we will review the advances in the identification and characterization of PCs for the MPS. These molecules, mainly based in molecules mimicking the enzyme substrates, have been described for MPS II, IVA, and IVB, showing a mutation-dependent enhancement of the mutated enzymes. Although the results show the potential of this strategy, further studies should focus in the development of disease-specific cellular models that allow a proper screening and evaluation of the identified PCs. In addition, in vivo evaluation, both pre-clinical and clinical, should be performed, before they can become a real therapeutic strategy for the treatment of MPS patients.