This paper develops mathematical models examining possible roles of oxytocin and oxytocin receptors in the development of autism. This is done by demonstrating that mathematical operations on normalized data from the Stanford study (K.J. Parker, 2016), which establishes a correspondence between severity of autism in children and their oxytocin blood levels, generates a graph that is the same as the graph of mathematical operations on a normalized theoretical model for the severity of autism. This procedure establishes the validity of the theoretical model and the significance of oxytocin receptors in autism. A steady-state model follows, explaining the constant baseline concentrations of oxytocin observed in the cerebral spinal fluid and blood in terms of the neuromodulation by oxytocin of oxytocin receptors on the magnocellular neurons that produce oxytocin in nuclei in the hypothalamus. The implications of these models for possible roles of oxytocin and oxytocin receptors in autism is considered for several unrelated conditions that may be associated with autism. These are: oxytocin receptor desensitization and down-regulation as factors during labor in offspring autism development; reductions in the oxytocin receptor numbers in the fixed oxytocin receptor expression that occurs before birth; MAST Immune System disease; and the excess number of dendritic spines from lack of pruning observed in brains of autistic people. Research into the feasibility of generating magnocellular neurons and other neurons from adult stem cells is suggested as a way of doing invitro studies of oxytocin and oxytocin receptors to assess the validity of theories presented in this paper.

Signaling from estrogen receptor alpha (ER) and its ligand estradiol (E2) is critical for growth of ~70% of breast cancers. Therefore, several drugs that inhibit ER functions are in clinical use for decades and new classes of anti-estrogens are continuously being developed. Although a significant number of ER+ breast cancers respond to anti-estrogen therapy, ~30% of these breast cancers recur, sometimes even after 20 years of initial diagnosis. Mechanism of resistance to anti-estrogens is one of the intensely studied disciplines in breast cancer. Several mechanisms have been proposed including mutations in ESR1, crosstalk between growth factor and ER signaling, and interplay between cell cycle machinery and ER signaling. ESR1 mutations as well as crosstalk with other signaling networks lead to ligand independent activation of ER thus rendering anti-estrogens ineffective, particularly when treatment involved anti-estrogens that do not degrade ERa. As a result of these studies, several therapies that combine anti-estrogens that degrade ER with PI3K/AKT/mTOR inhibitors targeting growth factor signaling or CDK4/6 inhibitors targeting cell cycle machinery are used clinically to treat recurrent ER+ breast cancers. In this review, we discuss nexus between ER-PI3K/AKT/mTOR pathways and how understanding of this nexus has helped to develop combination therapies.

Cellular communications play pivotal roles in multi-cellular species, but they do so also in uni-cellular species. Moreover, cells communicate with each other not only within the same individual but also with cells in other individuals belonging to the same or other species. These communications occur between two unicellular species, two multicellular species, or between unicellular and multicellular species. The molecular mechanisms involved exhibit diversity and specificity, but they share common basic features which allow common pathways of communication between different, and sometimes very different species. These interactions have been made possible by the high degree of conservation of the basic molecular mechanisms of interaction of many ligand-receptor pairs in evolutionary remote species. These inter-species cellular communications played crucial roles during Evolution and must have been positively selected, particularly when collectively beneficial in hostile environments. We think that communications between cells did not arise after their emergence but was part of the very nature of first cells. Synchronization of populations of non-living protocells through chemical communications may have been a mandatory step towards their emergence as populations of living cells and explain the large commonality of cell communication mechanisms among microorganisms, plants, and animals.

The signal transduction pathways of estrogen receptors (ER) mainly includes gene pathway and non-gene pathway. Studies have shown that the gene pathway of ER is related with the expression of nuclear proteins, and this is the key issue for our current research. With the GEO database analysis, Human centromere protein F (CENPF) is highly expressed in adenocarcinoma of lung (LUAD), and the co-expression of CENPF and ERβ was found in the nucleus of LUAD cells. Meanwhile, CENPF and ERβ2/5 were related with T stage and poor prognosis (P<0.05). Knockdown of CENPF gene significantly inhibited the biological effects of LUAD cells, the tumor growth of mice and the expression of ERβ2/5 (P<0.05). Further, group experiments showed that knockdown CENPF inhibits biological effects of LUAD cells mediated by ERβ pathway. All the results indicated that both CENPF and ERβ2/5 play important roles in the progression of LUAD, and knockdown of CENPF can inhibit the progression of LUAD by inhibiting the expression of ER2/5. Thus, the development of inhibitors against ERβ2/5 subtype and CENPF remained more effective in improving the therapeutic effect of LUAD.

Specific aquaporins (AQP), called peroxyporins, play a relevant role in controlling H2O2 permeability and ensure reactive oxygen species wasting during oxidative stress. Another target involved in oxidative stress is the Sigma1 Receptor (S1R), since its activation is triggered by oxidative or endoplasmic reticulum stress. Herein we evaluated the effect of S1R modulators on AQP-dependent water permeability in the presence and in the absence of oxidative stress. Applying stopped-flow light scattering and fluorescent probe methods, water and hydrogen peroxide permeability in Hela cells have been studied. Results evidenced that S1R agonists can restore water permeability in heat-stressed cells and the co-administration with a S1R antagonist totally counteracted the ability to restore the water permeability. All compounds except one were able to counteract the oxidative stress of HeLa cells specifically knocked down for S1R. Taken together, our results support the hypothesis that the investigated compounds act as dual aquaporin and Sigma1 receptor (DAS) modulators. The finding that small molecules can modulate both AQP and S1R opens a new direction toward the identification of innovative drugs able to regulate cell survival during oxidative stress in pathologic conditions, like cancer and degenerative diseases.

Melanocortins play crucial roles in regulating the stress response, inflammation, and skin pigmentation. In this review, we focus on the melanocortin 1 receptor (MC1R), a G protein-coupled receptor primarily known for regulating skin pigmentation and exhibiting anti-inflammatory effects. First, we provide an overview of the structure, signaling pathways, and related diseases of MC1R. Next, we discuss the potential therapeutic use of synthetic peptides and small molecule modulators of MC1R, highlighting the development of various drugs that enhance stability through amino acid sequence modifications and small molecule drugs to overcome limitations associated with peptide characteristics. Notably, MC1R-targeted drugs have applications beyond skin pigmentation-related diseases, which predominantly affect MC1R in melanocytes. These drugs can also be useful in treating inflammatory diseases with MC1R expression present in various cells. Our review underscores the potential of MC1R-targeted drugs to treat a wide range of diseases and encourages further research in this area.

Alpha-fetoprotein (AFP) is a major embryo- and tumor-associated protein capable of binding and transporting variety of hydrophobic ligands including estrogens. AFP has been shown to inhibit estrogen receptor (ER)-positive tumor growth and this can be attributed to its estrogen-binding ability. Despite AFP has long been investigated, its three-dimensional (3D) structure has not been experimentally resolved and molecular mechanisms underlying AFP-ligand interaction remain obscure. In our study we constructed homology-based 3D model of human AFP (HAFP) with the purpose to perform docking of ERα ligands, three agonists (17β-estradiol, estrone and diethylstilbestrol) and three antagonists (tamoxifen, afimoxifene and endoxifen) into the obtained structure. Based on ligand docked scoring function, we identified three putative estrogen- and antiestrogen-binding sites with different ligand binding affinities. Two high-affinity sites were located in (i) a tunnel formed within HAFP subdomains IB and IIA and (ii) opposite side of the molecule in a groove originating from cavity formed between domains I and III, while (iii) the third low-affinity site was found at the bottom of the cavity. 100 ns MD simulation allowed studying their geometries and showed that HAFP-estrogen interactions occur due to van der Waals forces, while both hydrophobic and electrostatic interactions were almost equally involved in HAFP-antiestrogen binding. MM/GBSA rescoring method estimated binding free energies (ΔG_bind) and showed that antiestrogens have higher affinities to HAFP as compared to estrogens. We performed in silico point substitutions of amino acid residues to confirm their roles in HAFP-ligand interactions and showed that Thr132, Leu138, His170, Phe172, Ser217, Gln221, His266, His316, Lys453, and Asp478 residues along two disulfide bonds, Cys224-Cys270 and Cys269-Cys277 have key roles in both HAFP-estrogen and HAFP-antiestrogen binding. Data obtained in our study contribute to understanding mechanisms underlying protein-ligand interactions and anti-cancer therapy strategies based on ER-binding ligands.

Angiotensin converting enzyme 2 (ACE2) is a key entry point of SARS-CoV-2 virus known to induce COVID-19. We have recently outlined the concept to reduce ACE2 expression by the administration of glycyrrhizin, a component of Glycyrrhiza glabra extract, via its inhibitory activity on 11beta hydroxysteroid dehydrogenase type 2 (11betaHSD2) and resulting activation of mineralocorticoid receptor (MR). We hypothesized that in organs, such as the intestine, which co-express 11betaHSD2, MR and ACE2, the expression of ACE2 would be suppressed. We studied organ tissues from an experiment originally designed to address the effects of Glycyrrhiza glabra extract on the stress response. Male Sprague Dawley rats were left undisturbed or exposed to chronic mild stress for five weeks. For the last two weeks, animals continued with a placebo diet or received a diet containing extract of Glycyrrhiza glabra root at a dose of 150 mg/kg of body weight/day. Quantitative PCR measurements showed a significant decrease in gene expression of ACE2 in the small intestine of rats fed with diet containing Glycyrrhiza glabra extract. This effect was independent of the stress condition and failed to be observed in non-target tissues, namely the heart and the brain cortex. In the small intestine we confirmed the reduction of ACE2 also at the protein level. Present findings provide first evidence to support the hypothesis that Glycyrrhiza glabra extract may reduce an entry point of SARS-CoV-2. Whether this phenomenon, when confirmed in additional studies, is linked to the susceptibility of cells to the virus requires further studies.

Despite exhaustive studies, researchers have made little progress in the field of adoptive cellular therapies for relapsed-refractory acute myeloid leukemia (AML), unlike the notable uptake for B cell malignancies. Various single antigen targeting chimeric antigen receptor (CAR) T cell Phase I trials have been established worldwide and have recruited approximately 100 patients. The high heterogeneity at the genetic and molecular levels within and between AML patients resembles a black hole: a great gravitational field that sucks in everything, considering only around 30% of patients show a response but with consequential off-tumor effects. It is obvious that a new point of view is needed to achieve more promising results. This review first introduces the unique therapeutic challenges of not only CAR T cells but also other adoptive cellular therapies in AML. Next, recent single cell sequencing data for AML to assess somatically acquired alterations at the DNA, epigenetic, RNA and protein levels are discussed to give a perspective on cellular heterogeneity, intercellular hierarchies, and the cellular ecosystem. Finally, promising novel strategies are summarized, including more sophisticated next-generation CAR T, TCR-T and CAR-NK therapies; approaches to tailor the microenvironment and target neoantigens; and allogeneic approaches.

Background. Epidemiological and clinical studies demonstrated that excessive salt intake causes severe hypertension and exacerbated organ derangement such as chronic kidney disease (CKD). In this study, we focused on evaluating histological and gene-expression findings in the kidney using stroke-prone spontaneously hypertensive rats (SHRSP) with high-salt intake and thromboxane A2/ prostaglandin H2 receptor (TPR) blocker ONO-8809. Methods. SHRSP aged 6 weeks were divided into three groups eating normal chow containing 0.4% NaCl, 2.0%NaCl, or 2.0%NaCl +ONO-8809 (0.6mg/kg p.o. daily). Histological analyses with immunohistochemistry and a gene-expression assay with a DNA kidney microarray were performed after 8 weeks. Results. The following changes were observed with high-salt intake. Glomerular sclerotic changes were remarkably observed in the juxtaglomerular cortex areas. ED1, MCP-1, nitrotyrosine, and HIF-1α staining areas were increased in the glomeruli and interstitial portion. Tbxa2r which encodes TPR, Prcp, and Car7 were significantly underexpressed in the kidney. The plasma 8-isoprostane level was significantly elevated, and was attenuated with ONO-8809 treatment. Conclusion. TXA2 and oxidative stresses exaggerated renal dysfunction in salt-loading SHRSP, and ONO-8809 as a TPR blocker suppressed these changes. Therefore, ONO-8809 is a candidate drug to prevent CKD for hypertensive patients associated with high-salt intake.

Abstract Optimal targeting of nanoparticles (NP) to dendritic cells (DCs) receptors to deliver cancer-specific antigens is key to an efficient induction of anti-tumor immune responses. Poly (lactic-co-glycolic acid) (PLGA) nanoparticles containing tètanus toxoid and gp100 melanoma-associated antigen, toll-like receptor adjuvants were targeted to the DC-SIGN receptor in DCs by specific humanized antibodies or by ICAM3-Fc fusion proteins mimicking natural ligand. Despite higher binding and uptake efficacy of anti-DC-SIGN antibody-targeted NP vaccines than ICAM3-Fc ligand, no difference were observed in DC activation markers CD80, CD83, CD86 and CCR7 induced. DCs loaded with NP coated with ICAM3-Fc appeared more potent in activating T cells via cross-presentation than antibody-coated NP vaccines. This fact could be very crucial in the design of new cancer vaccines.

Breast cancer (BC) is the most common type of cancer in both men and women alike, but it is more prevalent in women. Natural compounds that can modulate the oncogenic process can be considered a significant anti-cancer agent for treating BC. These natural compounds are more effective than synthetic drugs, which have profound side effects on the normal cell and resistance to cancer cells. Genistein is a type of dietary phytoestrogen included in the flavonoid group with a similar structure of estrogen that might provide a strong alternative and complementary medicine to existing chemotherapeutics drugs. Several research studies demonstrated that it can target the estrogen receptor (ER), Human epidermal growth factor receptor-2 (HER2), and Breast cancer gene-1 (BRCA-1) in multiple BC cell lines, as well as sensitize cancer cell lines to this compound when used at an optimal inhibitory concentration. Genistein effectively showed anti-cancer activities through apoptosis induction, arresting cell cycle, inhibiting angiogenesis with metastasis, reducing inflammation, mammosphere formation, tumor growth, up-regulating tumor suppressor gene, and downregulating oncogene in suppressing cancer progression in vitro and animal model study. In addition, research studies have also suggested that these phytochemicals synergistically reverse the resistance mechanism of chemotherapeutic drugs, increasing the efficacy of some chemoinformatics drugs. Our review article aims to unbox and validate the molecular pharmacology in breast tissue, cell-specific anti-cancer mechanism with synergistic activity, and possible pharmacokinetic parameters of Genistein as a potential alternative therapeutic option for the treatment of BC.

Since the detection of the first COVID-19 patient, 2 years have passed, during which more than 287,862,000 people fell ill globally, of which about 1.9% died. Implementation of SARS-CoV-2 control programs required efforts from almost all countries. An important direction in the fight against COVID-19 was the formation of herd immunity, the main tool for managing the pandemic. Study goal: to assess the seroprevalence of antibodies (Abs) to SARS-CoV-2 nucleocapsid (Nc) and receptor binding domain (RBD) in the St. Petersburg population during the COVID-19 pandemic. Materials and methods. A longitudinal cohort randomized monitoring study of Ab seroprevalence (SARS-CoV-2 Nc, RBD) was organized and conducted according to a unified methodology developed by Rospotrebnadzor with the participation of the St. Petersburg Pasteur Institute. For this purpose, a cohort of 1000 volunteers was formed who participated in all five stages of seromonitoring. The cohort was divided into 7 age groups: 1-17; 18-29; 30-39; 40-49; 50-59; 60-69; 70; and older (70+) years. Seropositivity levels (Nc, RBD) were assessed by quantitative and qualitative enzyme immunoassays. During the 2nd year of monitoring, some volunteers were vaccinated with the GamCOVIDVac (84%) or EpiVacCorona (11.6%) vaccines approved in Russia. Statistical processing was carried out using the Excel 2010 software package. Confidence intervals for shares and percentages (95% CI) were calculated using the method of A. Wald and J. Wolfowitz with adjustment (A. Agresti, B.A. Coull). The statistical significance of differences was calculated by z-test, using the appropriate online calculator (p<0.05), unless indicated. Results. There was a trend towards: an increase in Nc seropositivity in stages 1-3 of seromonitoring, with a decrease in stages 4-5 among children and adults. The share of RBD seropositive steadily increased during all 5 stages of seromonitoring. The most frequently found were low anti-RBD Abs levels (22.6-220 BAU/ml). High Ab levels were recorded statistically significantly less frequently. Asymptomatic forms were observed in 84-88% of SARS-CoV-2 seropositive volunteers. By the 5th stage of monitoring, this indicator significantly decreased to 69.8% (95% CI: 66.1-73.4). The monitoring revealed a statistically significant increase in anti-RBD Abs, alongside a statistically significant decrease in the proportion of Nc seropositive. This dynamic was especially characteristic of persons vaccinated with GamCOVIDVac. Conclusion. Prior to the use of specific vaccines, a seroprevalence of anti-Nc Abs was noted. After the introduction of the GamCOVIDVac vaccine in adults, a decrease in the level of anti-Nc Abs was noted due to an increase in the proportion of RBD seropositive persons.

Although congenital sensorineural hearing loss (SHL) in the bilateral cochleae mainly results from genetic abnormalities, chronic SHL progressing in later life is often influenced by systemic immune disturbances, including autoimmunity, chronic inflammation, and immunosenescence. We have investigated the relationship between the inner ear and systemic immunity and reviewed the possibilities to prevent SHL, including autoimmune SHL and age-related SHL. We also demonstrated two lymphocyte populations, interleukin 1 receptor type II (IL-1R2)-positive T cells (T1R2) and naturally occurring regulatory T cells (nTregs) in CD4⁺ T cells, which increase with aging, suppress host immune function and promote organ degeneration. Alterations in systemic immunity by fewer microbial antigen challenges in the living environment, elimination of immune suppressive lymphocytes, or immune rejuvenation with a reconstituted thymus may contribute not only to renew the cochlear function in SHL, but also to extend the healthy life of functional organs in a vigorous and youthful body, one of humanity’s greatest dreams.

Luteinizing hormone receptor (LHR) is a member of the seven-transmembrane (TM) receptor family. Several mutations in LHR have been identified in many mammalian species, leading to either constitutive activation or inactivation of the receptor. Mutations in highly conserved regions of the TM domain have been reported. In this study, we analyzed signal transduction by three constitutively active mutants (designated M410T, L469R, and D590Y) and two inactivating mutants (D383N and Y546F) of eelLHR known as naturally occurring in human LHR . To directly assess the functional effects of these mutations, site-directed mutant receptors were transiently expressed in CHO-K1 cells and cAMP accumulation stimulated by recombinant eelLH (rec-eelLH) was measured by homogeneous time-resolved fluorescence (HTRF) assays. The cAMP response in cells expressing eelLHR wild-type (eLHR-WT) increased in a dose-dependent manner with rec-eelLH ligand stimulation. Cells expressing the activating eelLHR mutants, M410T, L469R, and D590Y, exhibited a 4.0-, 19.1-, and 7.8-fold increase in basal cAMP response, respectively. However, their maximal responses were approximately 73, 53, and 92%, respectively, of the maximal response of LHR-WT. The L469R mutant exhibited a particularly marked increase in cAMP production in the absence of agonist. The maximal responses of the inactivating mutants, D383N and Y546F, were 32 and 24% of LHR-WT, respectively. However, the inactivating mutations did not completely impair signal transduction. Thus, we report here the first characterization of activating and inactivating mutations in eelLHR and we show that these mutations have similar effects as those reported for mammalian LHRs. Moreover, eelLHR with activating mutations showed constitutive cAMP responses. These results provide important data on the signal transduction of constitutively active and inactive LHR mutants. Further studies should aim to identify the mechanism responsible for the significant increase in basal cAMP response in the constitutively activated eelLHR mutants.

Theaflavins, the characteristic and bioactive polyphenols in black tea, possess the potential improvement effects on insulin resistance-associated metabolic abnormalities including obesity and type 2 diebetes. However, the molecular mechanisms of theaflavins improving insulin sensitivity are still not clear. In this study, we investigated the protective effects and mechanisms of theaflavins on palmitic acid-induced insulin resistance in HepG2 cells. Theaflavins could significantly increase glucose uptake of insulin-resistant cells at noncytotoxic doses. This activity was mediated by upregulating the glucose transporter 4 protein expression, increasing the phosphorylation of IRS-1 at Ser307, and reduced the phosphor-Akt (Ser473) level. Moreover, theaflavins were found to enhance mitochondrial DNA copy number through down-regulate the PGC-1β mRNA level and up-regulate PRC mRNA expression in insulin-resistant HepG2 cells. These results indicated that theaflavins could improve free fatty acid-induced hepatic insulin resistance by promoting mitochondrial biogenesis, and were promising functional food and medicines for insulin resistance-related disorders.

Gastroenteropancreatic neuroendocrine neoplasms (GEP NENs) are rare cancers consisting of neuroendocrine carcinomas (NECs) and neuroendocrine tumors (NETs), which have been increasing in incidence in recent years. Few cell lines and pre-clinical models exist for the study of GEP NECs and NETs, limiting the ability to discover novel imaging and treatment modalities. To address this gap, we isolated tumor cells from cryopreserved patient GEP NECs and NETs and injected them into the flanks of immunocompromised mice to establish patient-derived xenograft (PDX) models. Two of 6 mice developed tumors (NEC913 and NEC1452). Over 90% of NEC913 and NEC1452 tumor cells stained positive for Ki67. NEC913 PDX tumors expressed neuroendocrine markers such as chromogranin A (CgA), synaptophysin (SYP), and somatostatin receptor-2 (SSTR2) whereas NEC1452 PDX tumors do not express SSTR2. Exome sequencing revealed loss of p53 and RB1 in both tumors. To demonstrate an application of these novel NEC PDX models for SSTR2-targeted peptide imaging, the NEC913 and NEC1452 cells were bilaterally injected into mice. Near infrared-labelled octreotide was administered and fluorescent signal was specifically observed for the NEC913 SSTR2 positive tumors. These 2 GEP NEC PDX models serve as valuable resource for GEP NEN therapy testing.

Circulating tumor cells (CTCs) in the peripheral blood are the precursors to distant metastasis but the underlying mechanisms are poorly understood. This study aims at understanding the molecular features within CTCs in relation to their metastatic potential. Using in vitro CTC models, in which breast cancer cell lines are cultured in non-adherent conditions simulating the microenvironment in the blood stream, we found that suspension culture resulted in resistance to TNF-related apoptosis inducing ligand (TRAIL)-mediated cell death. Such a resistance was directly correlated with a reduction in surface and total levels of DR5 protein. In the non-adherent state, cells underwent rapid autophagic flux characterized by an accumulation of autophagosome organelles. Notably, DR5 was translocated to autophagosomes and underwent lysosomal degradation. Our data suggest that CTCs may evade TNF cytokine mediated immune surveillance through downregulation of DR expression. The data warrants further studies in cancer patients to find the status of DRs and other molecular features within primary CTCs in relation to disease progression or chemoresistance.

Bottlenose dolphin (Tursiops truncatus) belongs to the Cetartiodactyla and similarly to the other cetaceans represent the most successful mammalian colonization of the aquatic environment. Here we report a genomic, evolutionary and expression study of Tursiops truncatus T cell receptor beta (TRB) genes. Although the organization of the dolphin TRB locus is similar to that of the other artiodactyl species, with three in tandem D-J-C clusters located at its 3’ end, its uniqueness is given by the reduction of the total length due essentially to the absence of duplications and to the deletions that have drastically reduced the number of the germline TRBV genes. We have analyzed the relevant mature transcripts from two subjects. The simultaneous availability of rearranged TRA and TRB cDNA from the peripheral blood of one of the two specimens, and the human/dolphin amino acids multi sequence alignments, allowed us to calculate the most likely interactions at the protein interface between the alpha/beta heterodimer in complex with major histocompatibility class I (MH1) protein. Interacting amino acids located in the CDR-IMGT of the dolphin variable V alpha and beta domains were identified. According to comparative modelisation, the atome pair contact sites analysis between the human MH1 grove (G) domains and the TR V domains confirms conservation of the structure of the dolphin TR/pMH.

Neurokinin-1 receptor (NK-1R) antagonists exert an antitumor action, are safe and do not cause serious side-effects. These antagonists (via the NK-1R) exerted multiple actions against cancer: antiproliferative and anti-Warburg effects, apoptosis, anti-angiogenic and antimetastatic. These multiple effects have been shown in a broad-spectrum of cancers. The drug aprepitant (an NK-1R antagonist) is currently used in clinical practice as antiemetic. In in vivo and in vitro studies, aprepitant also showed the aforementioned multiple antitumor actions against many types of cancer. A successful combination therapy (aprepitant and radiotherapy) has recently been reported in a patient suffering from lung carcinoma: the tumor mass disappeared and side-effects were not observed. Aprepitant could be considered as an intelligent bullet against cancer. The administration of aprepitant in cancer patients to prevent recurrence and metastasis after surgical procedures, thrombosis and thromboembolism is discussed as well as the possible link, through the SP/NK-1R system, between cancer and depression. Our main aim is to review the multiple antitumor actions exerted by aprepitant and the use of this drug is suggested in cancer patients. Altogether, the data support the reprofiling of aprepitant for a new therapeutic use as an antitumor agent.

Several studies have demonstrated that the p75NTR low-affinity receptor of Nerve Growth Factor (NGF), is produced in abnormally large amounts in several human cancer types. However, the role of p75NTR varies substantially depending on cell context, so that a dual role of this receptor protein in tumor cell survival and invasion, as well as cell death, has been supported in recent studies. Herein we explored for the first time the expression of p75NTR in human specimens (nr=40) from testicular germ cell tumors (TGCTs), mostly seminomas. Nuclear overexpression of p75NTR was detected by immunohistochemistry in tumor tissue as compared to normal tissue, whereas neither NGF nor its high-affinity TrkA receptor was detected. An increased nuclear staining of phospho-JNK, belonging to the p75NTR signaling pathway, and its pro-apoptotic target gene, p53, was concomitantly observed. Interestingly, our analysis revealed that decreased expression frequency of p75NTR, p-JNK, and p53 was related to staging progression, thus suggesting that p75NTR may represent a specific marker of differentiation in TGCTs.

Life-threatening inflammatory conditions such as acute respiratory distress syndrome or sepsis often go hand in hand with severe vascular leakage. During inflammation, endothelial cell integrity and intact barrier function are crucial to limit leukocyte and plasma extravasation. Prostaglandin D₂ (PGD₂) is a potent inflammatory lipid mediator with vasoactive properties. It has been suggested that PGD^­₂ is involved in the regulation of endothelial barrier function; however, it is unclear whether this is also true for primary human pulmonary microvascular endothelial cells. Furthermore, as PGD₂ is a highly promiscuous ligand, we set out to determine which receptors are important in human pulmonary endothelial cells. In the current study, we found that PGD₂ and the DP1 agonist BW245c potently strengthened pulmonary and dermal microvascular endothelial cell barrier function and protected against thrombin-induced barrier disruption. Yet surprisingly, these effects were mediated only to a negligible extent via DP1 receptor activation. In contrast, we observed that the EP4 receptor was most important and mediated the barrier enhancement by PGD₂ and BW245c. These data demonstrate a novel mechanism by which PGD₂ may modulate inflammation and emphasizes the role of EP4 receptors in human endothelial cell function.

The ryanodine receptor (RyR) is a Ca2+ release channel in the sarcoplasmic reticulum of skeletal and cardiac muscles and plays a key role in excitation-contraction coupling. The activity of the RyR is regulated by many intracellular factors such as divalent cations (Ca2+ and Mg2+), nucleotides, associated proteins, and reactive oxygen species. Since these intracellular factors change depending on the condition of the muscle, e.g., exercise, fatigue, or disease states, the RyR channel activity will be altered accordingly. In this review, we describe how the RyR channel is regulated under various conditions and discuss the possibility that the RyR acts as a sensor for change in the cellular environment of muscles.

G protein-coupled receptors (GPCRs) serve prominent roles in melanocyte lineage physiology, with an impact at all stages of development, as well as on mature melanocyte functions. GPCR ligands are present in the skin and regulate melanocyte homeostasis, including pigmentation. The role of GPCRs in the regulation of pigmentation and, consequently, protection against external aggression, such as ultraviolet radiation, has long been established. However, evidence of new functions of GPCRs directly in melanomagenesis has been highlighted in recent years. GPCRs are coupled, through their intracellular domains, to heterotrimeric G proteins, which induce cellular signaling through various pathways. Such signaling modulates essential cellular processes of melanomagenesis, such as proliferation and migration. GPCR-associated signaling in melanoma can be activated by the binding of paracrine factors to their receptors or directly by activating mutations. In this review, we present melanoma-associated alterations of GPCRs and their downstream signaling and discuss the various preclinical models used to evaluate new therapeutic approaches against GPCR activity in melanoma. Recent striking advances in our understanding of the structure, function, and regulation of GPCRs will undoubtedly broaden treatment options in melanoma in the future.

In the United States (US), tianeptine is sold as a dietary supplement under the trade name Tianaa™. Tianeptine is a synthetic drug prescribed by physicians as an antidepressant in parts of Europe, Asia and South America. The drug is not permitted for use by physicians in the US, be-cause it is a μ-opioid receptor agonist with a propensity for severe addiction. As incidence of Tianaa™ related opioid addiction across the southern US escalate, the current study aimed to quantify tianeptine in over the counter Tianaa™ White, Red, and Green products. The results of this investigation measured tianeptine levels between 3.1 to 10.9 mg per 531 mg capsules. Tianaa™ White capsules consistently contained the least tianeptine, while Green had the most. Close inspection of Tianaa™ products showed that capsule mass varied by as much as 16% from label claim, and the amount of tianeptine per capsule varied by as much as 35 % from the aver-age measured amount for each product. Tianaa™ Red contains kava leaf extract, which led to the identification of four kavapyrone components by mass spectrometry. The data presented pro-vide insight into tianeptine quantity and capsule mass variation for Tianaa™ supplements sold to customers naive to the risk of addiction.

The proliferation and survival signals emanating from the B-cell receptor (BCR) constitute a crucial aspect of mature lymphocyte’s life. Dysregulated BCR signaling is considered a potent contributor to tumor survival in different subtypes of B cell non-Hodgkin lymphomas (B-NHLs). In the last decade, emergence of BCR-associated kinases as rational therapeutic targets has led to the development and approval of several small molecule inhibitors targeting either Bruton's tyrosine kinase (BTK), spleen tyrosine kinase (SYK), or phosphatidylinositol 3 kinase (PI3K), offering alternative treatment options to standard chemoimmunotherapy, and making some of these drugs valuable assets in the anti-lymphoma armamentarium. Despite their initial effectiveness, these precision medicine strategies are limited by primary resistance in aggressive B-cell lymphoma like diffuse large B cell lymphoma (DLBCL) and mantle cell lymphoma (MCL), especially in the case of first generation BTK inhibitors. In these patients, BCR-targeting drugs often fail to produce durable responses, and nearly all cases eventually progress with a dismal outcome, due to secondary resistance. This review will discuss our current understanding of the role of antigen-dependent and antigen-independent BCR signaling in DLBCL and MCL and will cover both approved inhibitors and investigational molecules being evaluated in early preclinical studies. We will discuss how the mechanisms of action of these molecules, and their off/on-target effects can influence their effectiveness and lead to toxicity, and how our actual knowledge supports the development of more specific inhibitors and new, rationally based, combination therapies, for the management of MCL and DLBCL patients.

Abstract: With the availability of an increasing number of 3D structures of bacteriophage components, combined with powerful in silico predictive tools, it has become possible to decipher the structural assembly and functionality of phage adhesion devices. In the current study, we examined 113 members of the 936 group of lactococcal siphophages, and identified a number of Carbohydrate Binding Modules (CBMs) in the neck passage structure and major tail protein, on top of evolved Dit proteins as recently reported by us. The binding ability of such CBM-containing proteins was assessed through the construction of green fluorescent protein fusion proteins and subsequent binding assays. Two CBMs, one from the phage tail and another from the neck, demonstrated definite binding to their phage-specific host. Bioinformatic analysis of the structural proteins of 936 phages reveals that they incorporate binding modules which exhibit structural homology to those found in other lactococcal phage groups and beyond, indicating that phages utilize common structural “bricks” to enhance host binding capabilities. The omnipresence of CBMs in Siphophages supports their beneficial role in the infection process, as they can be combined in various ways to form appendages with different shapes and functionalities, ensuring their success in host detection in their respective ecological niches.

(1) Background: Many malignancies are driven by mutations which affect the gene for fibroblast growth factor receptor (FGFR) 1. Previously we have documented that signal transduction from FOP2–FGFR1 fusion protein in KG1 cells downregulated the expression of vitamin D receptor (VDR) gene. In this paper we investigated if also other FGFRs were responsible for the regulation of the VDR expression. (2) Methods: We used human myeloid leukemia cells U937, and bone cancer cell line U2OS, and cell transfection methods in order to address the above questions. (3) Results: In myeloid leukemia cells overexpression of FGFR 1-4 caused shift to granulocytic differentiation, upregulated expression of VDR, and sensitized these cells to 1,25-dihydroxyvitamin D (1,25D)-induced monocytic differentiation, while in bone cells, signal transduction activated by FGF1 was not responsible for regulation of VDR expression and activity. (4) Conclusions: Since the overexpression of FGFRs occurs in many neoplasms, it may be reasonable to use 1,25D analogs in these cancers, in which overexpression of FGFRs leads to VDR upregulation.

Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) family that identify pathogen-associated molecular patterns derived from microbes and activate immune cell response. Following TLRs ligation, different adaptor and transcription molecules such as myeloid differentiation primary response gene 88 (MyD88) and nuclear factor kappa B (NF-kB) are recruited that initiate inflammatory signaling pathways. The human Toll-like receptor 10 (hTLR10) is a novel member of the PRRs family with a regulatory function of immune responses because of unique cytoplasmic domains which lead to induction of both inflammatory and anti-inflammatory properties. Recent studies have reported the association of TLR10 polymorphisms with many inflammatory diseases and human cancer. Engagement of TLR10 on the surface of the epithelium and macrophages leads to the production of proinflammatory cytokines and chemokines, while other studies have proven an anti-inflammatory role of TLR10. Accordingly, TLR10 suppresses proinflammatory cytokine production via negative regulation of MyD88 and the Akt (protein kinase B) and MAPK (mitogen-activated protein kinase) signaling pathways. This review aimed to provide answers for these conflicting findings (Inflammatory and anti-inflammatory properties of TLR10) to further identify distinct biological functions of TLR10.

Extracellular vesicles (EVs) effectively suppress neuroinflammation and induce neuroprotective effects in different disease models. However, the mechanisms by which EVs regulate neuroinflammatory response of microglia remain largely unexplored. Here, we addressed this issue by testing the action of EVs derived from human exfoliated deciduous teeth stem cells (SHEDs) on immortalized human microglial cells. We found that EVs induced a rapid increase in intracellular Ca2+ and promoted a significant ATP release in microglial after 20 min of treatment. Boyden chamber assays revealed that EVs promoted microglial migration by 20 %. Pharmacological inhibition of different subtypes of purinergic receptors demonstrated that EVs activated microglial migration preferentially through the P2X4R pathway. Proximity ligation and co-immunoprecipitation assays revealed that EVs promote association between milk fat globule-epidermal growth factor-factor VIII (MFG-E8) and P2X4 receptor proteins. Furthermore, pharmacological inhibition of αVβ3/αVβ5 integrin suppressed EV -induced cell migration and formation of lipid rafts in microglia. These results demonstrate that EVs promote microglial motility through P2X4 R/ MFG-E8 – dependent mechanisms. Our findings provide novel insights into the molecular mechanisms through which EVs target human microglia that may be exploited for the development of new therapeutic strategies targeting disease associated neuroinflammation.

In recent years, there have been frequent reports on the adverse effects of synthetic cannabinoid (SC) abuse. SCs cause psychoactive effects, similar to those caused by marijuana, by binding and activating cannabinoid receptor 1 (CB1R) in the central nervous system. The aim of this study was to establish a reliable quantitative structure-activity relationship (QSAR) model to correlate the structures and physicochemical properties of various SCs with their CB1R-binding affinities. We prepared 15 SCs and their derivatives (tetrahydrocannabinol [THC], naphthoylindoles, and cyclohexylphenols) and determined their binding affinity to CB1R, which is known as a dependence-related target. We calculated the molecular descriptors for dataset compounds using an R/CDK (R package integrated with CDK, version 3.5.0) toolkit to build QSAR regression models. These models were established and statistical evaluations were performed using the mlr and plsr packages in R software. The most reliable QSAR model was obtained from the partial least squares regression method via external validation. This model can be applied in vivo to predict the addictive properties of illicit new SCs. Using a limited number of dataset compounds and our own experimental activity data, we built a QSAR model for SCs with good predictability. This QSAR modeling approach provides a novel strategy for establishing an efficient tool to predict the abuse potential of various SCs and to control their illicit use.

Fusarium wilt of banana is a devastating disease that has decimated banana production worldwide. Host resistance to Fusarium oxysporum f. sp. cubense (Foc), the causal agent of this disease, is genetically dissected in this study using two Musa acuminata ssp. malaccensis segregating populations segregating for Foc Tropical (TR4) and Subtropical (STR4) race 4 resistance. Marker loci and trait association using 11 SNP-based PCR markers allowed the candidate region to be delimited to a 12.9 cM genetic interval corresponding to a 959 kb region on Chromosome 3 of ‘DH-Pahang’ reference assembly v4. Within this region, there is a cluster of pattern recognition receptors, namely leucine rich repeat ectodomain containing receptor-like protein kinases, cysteine-rich cell wall associated protein kinases, and leaf rust 10 disease-resistance locus receptor-like proteins positioned in an interspersed arrangement. Their transcript levels were rapidly upregulated in the resistant but not in susceptible F2 progenies at the onset of infection. This suggests that one or several of these genes may control resistance at this locus. To confirm the segregation of single-gene resistance, we generated an inter-cross between the resistant parent ‘Ma850’ and a susceptible line ‘Ma848’, to show that the STR4 resistance co-segregated with marker ‘28820’ at this locus. Finally, an informative SNP marker 29730 allowed the locus specific resistance to be assessed in a collection of diploid and polyploid banana plants. Out of the 60 lines screened, 22 lines were predicted to carry resistance at this locus, including lines known to be TR4 resistant, such as ‘Pahang’, ‘SH-3362’, ‘SH-3217’, ‘Ma-ITC0250’, and ‘DH-Pahang/CIRAD 930’. Additional screening in the International Institute for Tropical Agriculture’s collection suggests that the dominant allele is common among in the elite ‘Matooke’ NARITA hybrids, as well as in other triploid or tetraploid hybrids derived from East African highland bananas. Fine-mapping and candidate gene identification will allow characterization of molecular mechanisms underlying TR4 resistance. The markers developed in this study can now aid the marker-assisted selection of TR4 resistance in breeding programs around the world.

Killer immunoglobulin-like receptor (KIR) 2DL4 (CD158d) was previously thought to be a human NK-cell-specific protein but its expression has also been demonstrated in human mast cells. Mast cells are involved in allergic reactions via their KIT-mediated and IgE receptor-mediated responses. We recently detected the expression of KIR2DL4 in human cultured mast cells established from peripheral blood derived from healthy volunteers (PB-mast), a human mast cell line (LAD2), and non-neoplastic mast cells, including pathological specimens. An agonistic antibody against KIR2DL4 negatively regulates the KIT- and IgE-receptor-mediated responses of PB-mast and LAD2 cells. In addition, agonistic antibodies and human leukocyte antigen (HLA)-G, a natural ligand for KIR2DL4, induce the secretion from these cells of leukemia inhibitory factor and serine proteases, which have been implicated in pregnancy establishment and cancer metastasis. Therefore, KIR2DL4 stimulation with agonistic antibodies and recombinant HLA-G protein may enhance both processes, in addition to suppressing mast-cell-mediated allergic reactions.

We analyzed signal transduction of three constitutively activating mutants (M410T, L469R, and D590Y) and two inactivating mutants (D417N and Y558F) of the eel luteinizing hormone receptor (eel LHR), known to occur in human LHR. The objective of this study was to assess the functional effects of these mutations in signal transduction and cell surface loss of receptor. Mutant receptors were transiently expressed in Chinese hamster ovary (CHO-K1) cells. Eel LH-stimulated accumulation of cyclic adenosine monophosphate (cAMP) was measured by homogeneous time-resolved fluorescence (HTRF) assays. The loss of receptors from the cells surface was measured using an enzyme-linked immunosorbent assay (ELISA) in human embryonic kidney (HEK) 293 cells. The cAMP response in cells expressing the wild type eel LHR was increased in a dose-dependent manner using eel LH ligand stimulation. Compared with the wild type, cells expressing the activating mutants (M410T, L469R, and D590Y), exhibited a 4.0-, 19.1-, and 7.8-fold increase in basal cAMP response without agonist stimulation, respectively. Their maximal responses to agonist stimulation were approximately 65%, 52%, and 98%, respectively, of those of the wild type. The inactivating mutants (D417N and Y558F) did not completely impair signal transduction, and their maximal responses were only 33% and25 % of those of wild type. These data clearly showed that the eel LHR-L469R and D590Y, activating mutants enhanced the rate of the loss of cell surface receptors following treatment with eel LH. Thus, the loss of cell surface receptors in cells expressing mutant eel LHRs was consistent with the eel LH agonist-induced production of cAMP. Our results suggested that the activation of the eel LHR requires appropriate loss of LHR-ligand complexes from the cell surface.

Autophagy, an alternative cell death mechanism, is also termed programmed cell death type II. Autophagy in cancer treatment needs to be regulated. In our study, autophagy inhibition by desipramine or the autophagy inhibitor chloroquine (CQ) enhanced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-2 [death receptor (DR5)] expression and subsequently TRAIL-induced apoptosis in TRAIL-resistant A549 lung cancer cells. Genetic inhibition of DR5 substantially reduced desipramine-enhanced TRAIL-mediated apoptosis, proving that DR5 was required to increase TRAIL sensitivity in TRAIL-resistant cancer cells. Desipramine treatment upregulated p62 expression and promoted conversion of light chain 3 (LC3)-I to its lipid-conjugated form, LC3-II, indicating that autophagy inhibition occurred at the final stages of autophagic flux. Transmission electron microscopy analysis showed the presence of condensed autophagosomes, which resulted from the late stages of autophagy inhibition by desipramine. TRAIL, in combination with desipramine or CQ, augmented the expression of apoptosis-related proteins cleaved caspase-8 and cleaved caspase-3. Our results contributed to the understanding of the mechanism underlying the synergistic anti-cancer effect of desipramine and TRAIL and presented a novel mechanism of DR5 upregulation. These findings demonstrated that autophagic flux inhibition by desipramine potentiated TRAIL-induced apoptosis, suggesting that appropriate regulation of autophagy is required for sensitizing TRAIL-resistant cancer cells to TRAIL-mediated apoptosis.

Indirubin-3′-monoxime (I3M) exhibits anti-proliferative activity in various cancer cells; however, its anti-cancer mechanism remains incompletely elucidated. This study revealed that I3M promotes the expression of death receptor 5 (DR5) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) in HCT116 p53+/+ cells, resulting in caspase-mediated apoptosis. However, this study demonstrated that HCT116 p53-/- cells are insensitive to I3M-mediated apoptosis, indicating that I3M-induced apoptosis depends on the p53 status of HCT116 cells. Additionally, in HCT116 p53-/- cells, I3M significantly increased Ras expression, while in HCT116 p53+/+ cells, it reduced Ras expression. Furthermore, I3M remarkably increased the production of reactive oxygen species (ROS), which were reduced in transient p53 knockdown, indicating that I3M-mediated apoptosis is promoted by p53-mediated ROS production. Our results also showed that I3M enhanced transcription factor C/EBP homologous protein (CHOP) expression, resulting in endoplasmic reticulum (ER) stress-mediated DR5 expression, which is upregulated by ROS production in HCT116 p53+/+ cells. Moreover, co-treatment with TRAIL synergistically enhanced I3M-induced DR5 expression, thereby triggering TRAIL-induced apoptosis of HCT116 p53+/+ cells, which was interfered by a DR5-specific blocking chimeric antibody. In summary, I3M potently enhances TRAIL-induced apoptosis by upregulating DR5 expression via p53-mediated ROS production in HCT116 p53+/+ cells. However, HCT116 p53-/- cells were resistant to I3M-mediated apoptosis, suggesting that I3M could be a promising anti-cancer candidate against TRAIL-resistant p53+/+ cancer cells.

Type 2 Diabetes Mellitus (T2DM) is associated with a high risk of atherosclerotic cardiovascular (CV) disease. Contributing pathophysiologic factors include endothelial dysfunction caused by excessive production of reactive oxygen species (ROS), increased activity of nuclear factor kB (NFkB), altered macrophage polarization, and reduced synthesis of endothelial progenitor cells (EPC). Consequently, there can be a potentially rapid progression of the atherosclerotic disease with a higher propensity to unstable plaque, leading to increased cardiovascular mortality. Management is aimed at prevention, early diagnosis, and treatment of hyperglycemia and vascular complications. Innovative therapeutic approaches for T2DM seek to customize the antidiabetic treatment to each patient in order to optimize glucose-lowering effects, minimize hypoglycemia and adverse effects, and prevent cardiovascular events. The newer drugs (Glucagon Like Peptide-1 Receptor Agonists, GLP-1 RAs; Sodium GLucose coTransporter-2 inhibitors, SGLT2is; DiPeptidyl Peptidase-4 inhibitors, DPP4is) impact body weight, lipid parameters, and blood pressure, as well as endothelial function, inflammatory markers, markers of oxidative stress, and subclinical atherosclerosis. The present review summarizes the results of trials that evaluated the cardiovascular safety of these drugs and found them to be safe from the CV standpoint.

Understanding of the molecular mechanisms of prostate cancer has led to development of therapeutic strategies targeting androgen receptor (AR). These androgen-receptor signaling inhibitors (ARSI) include androgen synthesis inhibitor- abiraterone and androgen receptor antagonists- enzalutamide, apalutamide, and darolutamide. Although these medications provide significant improvement in survival among men with prostate cancer, drug resistance develops in nearly all patients with time. This could be through androgen-dependent or androgen-independent mechanisms. Even weaker signals and non-canonical steroid ligands can activate AR in the presence of truncated AR-splice variants, AR overexpression, or activating mutations in AR. AR splice variant, AR-V7 is the most studied among these and is not targeted by available ARSIs. Non-androgen receptor dependent resistance mechanisms are mediated by activation of an alternative signaling pathway when AR is inhibited. DNA repair pathway, PI3K/AKT/mTOR pathway, BRAF-MAPK and Wnt signaling pathway and activation by glucocorticoid receptors can restore downstream signaling in prostate cancer by alternative proteins. Multiple clinical trials are underway exploring therapeutic strategies to overcome these resistance mechanisms.

Cardiac β₂-adrenergic receptors (ARs) are known to inhibit collagen production and fibrosis in cardiac fibroblasts and myocytes. The β₂AR is a Gs protein-coupled receptor (GPCR) and, upon its activation, stimulates generation of cyclic 3', 5'-adenosine monophosphate (cAMP). cAMP has two effectors: protein kinase A (PKA) and the exchange protein directly activated by cAMP (Epac). Epac1 has been shown to inhibit cardiac fibroblast activation and fibrosis. Osteopontin (OPN) is a ubiquitous pro-inflammatory cytokine, mediating also fibrosis in several tissues, including the heart. OPN underlies several cardiovascular pathologies, including atherosclerosis and cardiac adverse remodeling. We have found that the cardiotoxic hormone aldosterone transcriptionally upregulates OPN in H9c2 rat cardiac myoblasts, an effect prevented by endogenous β₂AR activation. Additionally, CRISPR-mediated OPN deletion enhances cAMP generation in response to both b₁AR and β₂AR activation in H9c2 cardiomyocytes, leading to upregulation of Epac1 protein levels. These effects render β₂AR stimulation capable of completely abrogating transforming growth factor (TGF)-β-dependent fibrosis in OPN-lacking H9c2 cardiomyocytes. Finally, OPN interacts constitutively with G_as subunits in H9c2 cardiac cells. Thus, we have uncovered a direct inhibitory role of OPN in cardiac β₂AR anti-fibrotic signaling via cAMP/Epac1. OPN blockade could be of value in the treatment and/or prevention of cardiac fibrosis.

Natural and synthetic small molecules from the NCI Developmental Therapeutics Program (DTP) were employed in molecular dynamics-based docking with DNA repair proteins whose RNA-Seq based expression was associated with overall cancer survival (OS) after adjustment for the PCNA metagene. The compounds employed were required to elicit a sensitive response (vs. resistance) in more than half of the cell lines tested for each cancer. Methodological approaches included peptide sequence alignments and homology modeling for 3D protein structure determination, ligand preparation, docking, toxicity and ADME prediction. Docking was performed for unique lists of DNA repair proteins which predict OS for AML, cancers of the breast, lung, colon, and ovaries, GBM, melanoma, and renal papillary cancer. Results indicate hundreds of drug-like and lead-like ligands with best-pose binding energies less than -6 kcal/mol. Ligand solubility for the top 20 drug-like hits approached lower bounds, while lipophilicity was acceptable. Most ligands were also blood-brain barrier permeable with high intestinal absorption rates. While the majority of ligands lacked positive prediction for Herg channel blockage and Ames carcinogenicity, there was considerable variation for predicted fathead minnow, honey bee, and Tetrahymena pyriformis toxicity. The computational results suggest the potential for new targets and mechanisms of repair inhibition and can be directly employed for in vitro and in vivo confirmatory laboratory experiments to identify new targets of therapy for cancer survival.

The different cell subsets of the immune system express vitamin D receptor (VDR). Through VDR, vitamin D exerts different functions which influences on immune responses, as previously shown in different preclinical models. Based on this background, retrospective studies have explored the impact of vitamin D levels on the outcome of patients undergoing allogeneic hematopoietic stem cell transplantation, showing that vitamin D deficiency is related to an increased risk of complications, especially graft-versus-host disease. These results have been confirmed in a prospective cohorts trial, although further studies are required to confirm this data. In addition, the role of vitamin D on the treatment of hematologic malignancies has also been explored. Considering this dual effect both on the immune system as well as on tumor cells in patients with hematologic malignancies, vitamin D might be useful in this setting both to decrease graft-versus-host disease and relapse rates.

Androgen insensitivity syndrome (AIS) is the most common disorder of sex development in people with karyotype 46,XY. Mutations in AR (androgen receptor) gene are found in most individuals with AIS. Exons 4-8, which encode LBD, were shown to be a mutation hotspot. The aim of this study was the search of mutations in the sequence of exons 6-8 which encode LBD of AR gene in patients with different clinical AIS phenotypes from Ukraine. The investigated patients were 4 women with 46,XY karyotype, SRY-positive and clinical features of AIS (2 – CAIS, 2 – PAIS). Serum levels of T, LH, and FSH were quantified by electrochemiluminescence immunoassay (ECLIA) technology. Cytogenetic studies were performed on peripheral blood lymphocytes with further use of standard protocols of chromosomal analysis (GTG-banding). The presence of SRY sequence was confirmed by FISH with LSI SRY probe. Direct Sanger sequencing of 6-8 exons was performed in patients and family members on the PCR products on the matrix of DNA samples isolated from peripheral blood lymphocytes. Detected SNPs were analysed using gnomAD, VEP, MutationTaster, Human Splicing Finder, NetPhorest 2.1, Group-based Prediction System 5.0, and PhosphoPICK bioinformatical resources. Modelling of mutant proteins based on available 3D models was conducted using the open source software UCSF Chimera 1.14rc. We have detected 3 previously described mutations (missense mutation X:67722905 Т>С (rs9332970) in PAIS patient, missense mutation X:67722943 C>T (rs886041132) in CAIS patient and, samesense mutation X:67723745 C>T (rs137852594) in PAIS patient). We determined these mutations as pathogenic using SIFT, PolyPhen, MutationTaster, Human Splicing Finder. Moreover the synonymous mutation X:67723745 C>T (rs137852594) detected in patient with PAIS was determined as mutation affecting processes of splicing. In our study we have identified novel mutation X:67722884 T>G in CAIS patient and family members. This mutation was predicted as a pathogenic using aforementioned bioinformatical tools. STRUM calculations of the protein stability change caused by single-point mutation showed a destabilization effect of the Ile836Ser substitution ΔΔG=-2.6. Possible aberrant phosphorylation analysis revealed the ability of MAPK family, Akt family, CDK1, CDK7, CDK9, PKC kinases to phosphorylate Ser836. Results concerning the pathogenicity of X:67722905 Т>С (rs9332970), X:67722943 C>T (rs886041132), X:67723745 C>T (rs137852594) mutations detected in patients with AIS from Ukraine obtained using bioinformatical resources SIFT, PolyPhen, MutationTaster, Human Splicing Finder correlate with previously published data concerning weaker binding of androgens in patients with the same mutations. This approves informativity of using such resources for mutation pathogenicity analysis. Analysis of the ortholog proteins, subdomain structure, and aberrant phosphorylation of AR-LBD suggests novel X:67722884 T>G mutation to be pathogenic. Based on analysis of mutant protein modelling followed by assessment of free energy change using STRUM it was predicted that mutant protein binds androgens 460 times worse than wild type.

Accumulating evidence suggests that histamine synthesis induced in several types of tumor tissues should modulate tumor immunity. We found that a transient histamine synthesis was induced in CD11b⁺Gr-1⁺splenocytes derived from BALB/c mice transplanted with a syngeneic colon carcinoma, CT-26, when they were co-cultured with CT-26 cells. Significant levels of IFN-γ were produced under this co-culture condition. We explored the modulatory roles of histamine on IFN-γ production and found that several histamine receptor antagonists, such as pyrilamine, diphenhydramine, JNJ7777120, and thioperamide, could significantly suppress IFN-γ production. However, suppression of IFN-γ production by these antagonists was also found when splenocytes were derived from the Hdc^-/- BALB/c mice. Suppressive effects of these antagonists were found on IFN-γ production induced by concanavalin A or the combination of an anti-CD3 antibody and an anti-CD28 antibody in a histamine-independent manner. Murine splenocytes were found to express H₁ and H₂ receptors, but not H₃ and H₄ receptors. IFN-γ production in the Hh1r^-/- splenocytes induced by the combination of an anti-CD3 antibody and an anti-CD28 antibody was significantly suppressed by these antagonists. These findings suggest that pyrilamine, diphenhydramine, JNJ7777120, and thioperamide could suppress IFN-γ production in activated splenocytes in histamine-independent manner.

The role of γδ T cells in vertebrate immunity is still an unsolved puzzle. Species such as humans and mice display a low percentage of these T lymphocytes (i.e., “γδ low species”) with a restricted diversity of γδ T cell receptors (TR). Conversely, artiodactyl species (i.e., “γδ high species”) ac-count for a high proportion of γδ T cells with large γ and δ chain repertoires. The genomic organisation of the TR γ (TRG) and δ (TRD) loci has been determined in sheep and cattle, noting that a wide number of germline genes that encode for γ and δ chains characterise their genomes. Taking advantage from the current improved version of the genome assembly, we have investigated the genomic structure and gene content of the dromedary TRD locus, which, as in the other mammalian species, is nested within the TR alpha (TRA) genes. The most remarkable finding was the identification of a very limited number of variable germline genes (TRDV) compared to sheep and cattle, which supports our previous expression analyses for which the somatic hypermutation mechanism is able to enlarge and diversify the primary repertoire of dromedary δ chains. Furthermore, the comparison between genomic and expressed sequences reveals that D genes, up to four incorporated in a transcript, greatly contribute to the increased diversity of the dromedary δ chain antigen binding-site.

Migraine and neuropathic pain (NP) are evocative of painful, disabling, chronic conditions which exhibit resembling symptoms and thus considered to share a common etiology. Calcitonin gene-related peptide (CGRP) has gained credit as a target for migraine management; nevertheless, the efficacy and the applicability of CGRP modifiers warrant search for more effective therapeutic targets for pain management. This scoping review overviews human studies of common pathogenic factors in migraine and NP to explore potential novel therapeutic targets. CGRP causes inflammation in the meninges; monoclonal antibodies and inhibitors target CGRP. Gluta-mate-induced hyperexcitability and subsequent sensitization are closely linked to an alteration of the tryptophan (Trp)-kynurenine (KYN) metabolic system; the Trp-KYN system may serve as a potential target. Microglial overaction is observed in migraine and NP; modifying the microglial activity may be a possible approach. Cytokine-induced inflammation is a leading hypothesis of the pathogenesis of the conditions; alleviating neuroinflammation may complement a pain-relieving armamentarium. Transient receptor potential (TRP) ion channels evoke the release of several substances; TRP ion channels may potentially emerge as new targets. The endocannabinoid system plays a major role in the pain trafficking pathway; modification of the system may open a new path toward discovery of new analgesics. Here we highlight the mechanism of those common pathogenic factors to explore therapeutic targets for innovative pain management in migraine and NP.

(1) Background: To fight for COVID-19 pandemic, immunity against SARS-CoV-2 should be achieved not only through natural infection but also vaccination. Controversies exist about the effect of COVID-19 vaccination on previously infected persons; (2) Methods: A prospective cohort was undergone to collect sera from unvaccinated survivors and vaccinated persons--with and without COVID-19 pre-infection. The sera were analyzed for the anti-Receptor Binding Domain (RBD) titers by ELISA and for the capacity to neutralize the pseudovirus of the Wuhan-Hu-1 strain by luciferase assays; (3) Results; Neither the antibody titers nor the neutralization capacity was significantly different between the three groups. However, the correlation between the antibody titers and the percentage of viral neutralization derived from sera of unvaccinated survivors was higher than that from vaccinated persons with pre-infection (Spearman correlation coefficient (r) = -0.8558; 95% CI, -0.9259 to -0.7288), p &lt;0.0001 vs -0. 581; 95% CI, -0.7679 to -0.3028; p = 0.0002, respectively), indicating the capacity to neutralize the virus is better among the unvaccinated individuals. (4) Conclusions: Vaccines induced anti-RBD titers as high as the natural infection with lower neutralization capacity, and it did not boost the immunity in pre-infected persons.

Background: Real-world data on the molecular epidemiology of EGFR resistance mutations at or after progression with first- or second-generation EGFR-TKIs in patients with advanced NSCLC are lacking. Methods: This ongoing observational study was carried out by 23 hospital-based physicians in Greece. The decision to perform Cobas® EGFR Mutation Test v2 in tissue and/or plasma at disease progression was made before enrollment. For patients with negative/inconclusive T790M plasma-based results, tissue re-biopsy could be performed. Results: Ninety-six (96) eligible patients were consecutively enrolled (median age: 67.8 years) between July-2017 and September-2019. Of the patients, 98% were tested upon progression using plasma and 2% using tissue/cytology biopsy. The T790M mutation was detected in 16.0% of liquid biopsies. Tissue re-biopsy was performed in 22.8% of patients with a T790M-negative plasma result. In total, the T790M positivity rate was 21.9%, not differing between patients on first- or second-generation EGFR-TKI. Higher (≥2) ECOG performance status and longer (≥10 months) time to disease progression following EGFR-TKI treatment initiation were associated with T790M positivity. Conclusions: Results from plasma/tissue-cytology samples in a real-world setting, yielded a T790M positivity rate lower than previous reports. Fewer than one in four patients with negative plasma-based testing underwent tissue re-biopsy, indicating the challenges in routine care settings.

Obesity-associated metabolic abnormalities comprise of a cluster of conditions including dyslipidemia, insulin resistance, diabetes, and cardiovascular diseases that has affected more than 650 million people all over the globe. Obesity results from accumulation of white adipose tissues mainly due to the chronic imbalance of energy intake and energy expenditure. Variety of approaches to treat or prevent obesity, including lifestyle interventions, surgical weight loss procedures and pharmacological approaches to reduce energy intake and increase energy expenditure have failed to substantially decrease the prevalence of obesity. Brown adipose tissue (BAT), the primary source of thermogenesis in infants and small mammals may represent a promising therapeutic target to treat obesity by promoting energy expenditure through non-shivering thermogenesis mediated by mitochondrial uncoupling protein 1 (UCP1). Since the confirmation of functional BAT in adult humans by several groups, approximately a decade ago and its association with a favorable metabolic phenotype, intense interest on the significance of BAT in adult human physiology and metabolic health has emerged within the scientific community to explore its therapeutic potential for the treatment of obesity and metabolic diseases. Substantially decreased BAT activity in individuals with obesity indicates a role for BAT in setting of human obesity. On the other hand, BAT mass and its prevalence has been reported to correlate with lower body mass index (BMI), decreased age and glucose levels, leading to lower incidence of cardio metabolic diseases. Increased cold exposure in adult humans with undetectable BAT was associated with decreased body fat mass and increased insulin sensitivity. Deeper understanding of the role of BAT in human metabolic health and its inter-relationship with body fat distribution and deciphering proper strategies to increase energy expenditure by either increasing functional BAT mass, or inducing white adipose browning holds the promise for possible therapeutic avenues for the treatment of obesity and associated metabolic disorders.

Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Currently, there are no reports on the mycobacterial components that regulate PGE2 production. Previously, we have reported that RpfE-treated dendritic cells (DCs) effectively expanded the Th1 and Th17 cell responses simultaneously; however, the mechanism underlying Th1 and Th17 cell differentiation is unclear. Here, we show that PGE2 produced by RpfE-activated DCs via the MAPK and cyclooxygenase 2 signaling pathways induces Th1 and Th17 cell responses mainly via the EP4 receptor. Furthermore, mice administered intranasally with PGE2 displayed RpfE-induced antigen-specific Th1 and Th17 responses with a significant reduction in bacterial load in the lungs. Furthermore, the addition of optimal PGE2 amount to IL-2-IL-6-IL-23p19-IL-1β was essential for promoting differentiation into Th1/Th17 cells with strong bactericidal activity. These results suggest that RpfE-matured DCs produce PGE2 that induces Th1 and Th17 cell differentiation with potent anti-mycobacterial activity.

Pemphigus vulgaris is an autoimmune blistering disease of the epidermis, caused by autoantibodies against desmosomal proteins, mainly desmogleins 1 and 3, which induce an impairment of desmosomal adhesion and blister formation. Recent findings have shown that inhibition of immunoglobulin G binding on the neonatal Fc receptor, FcRn, results in reduced autoantibody recycling and shortens their half-life, providing a valid treatment option for PV. We have here analyzed the role of FcRn in human keratinocytes treated with novel, recombinant anti-desmoglein-3 antibodies that induce pathogenic changes in desmosomes, such as loss of monolayer integrity, aberrant desmoglein-3 localization and degradation of desmoglein-3. We show that blocking IgG binding on FcRn by efgartigimod, a recombinant Fc fragment that is undergoing clinical studies for pemphigus, stabilizes the keratinocyte monolayer, whereas the loss of desmoglein-3 is not prevented by efgartigimod. Our data show for the first time that FcRn may play a direct role in the pathogenesis of pemphigus at the level of the autoantibody target cells, the epidermal keratinocytes. Our data also imply that in keratinocytes, FcRn may have functions different from its known function in IgG recycling. Therefore, stabilization of keratinocyte adhesion by FcRn blocking entities may provide a novel treatment paradigm for pemphigus.

The endocannabinoid system (eCB) began to be studied from the identification of the molecular structures present in the cannabis sativa plant. The ECS is constituted of cannabinoid receptors, endogenous ligands and all the associated enzymatic apparatus responsible for maintaining homeostasis. Several physiological effects of cannabinoids are exerted through interaction with various receptors such as CB1 and CB2 receptors, vanilloid receptors, and the recently discovered [GPCRs (GPR55, GPR3, GPR6, GPR12 and GPR19). Endogenous ligands such anandamide and 2-arachidonoylglycerol might modulate these receptors. eCB has proved to play a critical role in some human diseases and has been extensively studied due to its wide therapeutic potential and because it is a promising target for the development of new drugs. Phytocannabinoids and synthetic cannabinoids have shown varied affinities to eCB, which are relevant to the treatment of various diseases. They may also have potential as lead compounds in the development of cannabinoid-based pharmaceuticals for a variety of diseases. Furthermore, Integrative and Complementary Health Practices (ICHP) appear to influence the endocannabinoid system through modulation. This review will show a description of ECS components and discuss how phytocannabinoids, other exogenous compounds, and PICS may operate the eCB balance.

Substances that can modify the androgen receptor pathway in humans and animals are entering the environment and food chain with the proven ability to disrupt hormonal systems and leading to toxicity and adverse effects on reproduction, brain development, and prostate cancer, among others. State-of-the-art databases with experimental data of human, chimp, and rat effects by chemicals have been used to build machine learning classifiers and regressors and evaluate these on independent sets. Different featurizations, algorithms, and protein structures lead to dif- ferent results, with deep neural networks (DNNs) on user-defined physicochemically-relevant features developed for this work outperforming graph convolutional, random forest, and large featurizations. The results show that these user-provided structure-, ligand-, and statistically-based features and specific DNNs provided the best results as determined by AUC (0.87), MCC (0.47), and other metrics and by their interpretability and chemical meaning of the descriptors/features. In addition, the same features in the DNN method performed better than in a multivariate logistic model: validation MCC = 0.468 and training MCC = 0.868 for the present work compared to evalu- ation set MCC = 0.2036 and training set MCC = 0.5364 for the multivariate logistic regression on the full, unbalanced set. Techniques of this type may improve AR and toxicity description and predic- tion, improving assessment and design of compounds. Source code and data are available at https://github.com/AlfonsoTGarcia-Sosa/ML

The interactions of chemotherapeutic drugs with nanocage protein apoferritin (APO) are the key features in the effective encapsulation and release of highly toxic drugs in APO-based controlled drug delivery systems. The encapsulation enables mitigating the drugs side effects, collateral damage to healthy cells, and adverse immune reactions. Herein, the interactions of anthracycline drugs with APO were studied to assess the effect of drug lipophilicity on their encapsulation excess n and in vitro activity. Anthracycline drugs, including doxorubicin (DOX), epirubicin (EPI), daunorubicin (DAU), and idarubicin (IDA), with lipophilicity P from 0.8 to 15, were investigated. We have found that in addition to hydrogen-bonded supramolecular ensemble formation with n = 24, there are two other competing contributions that enable increasing n under strong polar interactions (APO(DOX)) or under strong hydrophobic interactions (APO(IDA) of the highest efficacy). The encapsulation/release processes were investigated using UV-Vis, fluorescence, circular dichroism, and FTIR spectroscopies. In vitro cytotoxicity/growth inhibition tests and flow cytometry corroborate high apoptotic activity of APO(drugs) against targeted MDA-MB-231 adenocarcinoma and HeLa cancer cells, and low activity against non-tumorigenic MCF10A cells, demonstrating targeting ability of nanodrugs. A model for molecular interactions between anthracyclines and APO nanocarriers was developed, and the relationships derived compared with experimental results.

Astronauts at are risk of losing 1.0 – 1.5% of their bone mass for every month they spend in space despite their adherence to high impact exercise training programs designed to preserve the musculoskeletal system. This article reviews the basics of bone formation and resorption and details how exposure to microgravity or simulated microgravity affects the structure and function of osteoblasts, osteocytes, osteoclasts, and their mesenchymal and hematologic stem cell precursors. It details the critical roles that insulin-like growth facor-1 and its receptor IGFR1 play in maintaining bone homeostasis and how exposure of bone cells to microgravity affects the function of these growth factors. Lastly, it discusses the potential of tumor necrosis factor-related apoptosis-inducing ligand, syncytin-A, and sclerostin inhibitors and recombinant IGF-1 as a bone-saving treatment for astronauts in space and during their colonization of the Moon.

Endocytosis in mammalian cells is a fundamental cellular machinery that regulates vital physiological processes, such as the absorption of metabolites, release of neurotransmitters, hormonal secretion, cellular defense, and delivery of biomolecules across the plasma membrane. A remarkable characteristic of the endocytic machinery is the sequential assembly of the complex proteins at the plasma membrane followed by transportation of various cargo molecules to different cellular compartments. In all eukaryotic cells, functional characterization of endocytic pathways is based on dynamics of the protein complex modules. To coordinate the assembly and functions of the numerous parts of the endocytic machinery, the endocytic proteins interact significantly within and between the modules. Clathrin dependent and independent endocytosis, caveolar pathway and receptor mediated endocytosis have been attributed in a greater variety of physiological and pathophysiological roles such as, autophagy, metabolism, cell division, apoptosis, cellular defense, and intestinal permeabilization. Notably, any defect or alteration in the endocytic machinery results in the development of pathological consequences associated with human diseases such as cancer, cardiovascular diseases, neurological diseases, and inflammatory diseases. In this review, an in-depth endeavor has made to illustrate the process of endocytosis, and associated mechanisms describing pathological manifestation associated with dysregulated endocytosis machinery.

Meningioma (MGM) is the most common type of intracranial tumor in adults. The validation of novel prognostic biomarkers to better inform tumor stratification and clinical prognosis is urgently needed. Many molecular and cellular alterations have been described in MGM tumors over the past few years, providing a rational basis for the identification of biomarkers and therapeutic targets. The role of receptor tyrosine kinase (RTKs), including those of the ErbB family of receptors, as oncogenes has been well established in several cancer types. Here, we review histological, molecular, and clinical evidence suggesting that RTKs, including the epidermal growth factor receptor (EGFR, ErbB 1), as well as other members of the ErbB family, may be useful as biomarkers in MGM.

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.

A separate group consists of compounds that are able to simultaneously interact with both orthosteric and allosteric sites, which are classified as bitopic GPCR ligands [74, 76-81]. They have two pharmacophores, one of which binds with high affinity to the orthosteric site, while the other, with lower affinity, binds to the allosteric site. If these sites are spatially separated in the receptor, then the pharmacophores in the bitopic ligand must be connected with a flexible linker, the length of which exactly corresponds to the distance between the orthosteric and allosteric sites. At the same time, it is important that the linker does not significantly affect the conformational rearrangements in the receptor caused by its activation by orthosteric and (or) allosteric agonists [74, 79].

Ophelia syndrome is characterized by the coincidence of severe neuropsychiatric symptoms, classical Hodgkin lymphoma, and the presence of antibodies to the metabotropic glutamate 5 receptor (mGluR5). Little is known about the pathogenetic link between these symptoms and the role that anti-mGluR5-antibodies play. We investigated lymphoma tissue from patients with Ophelia syndrome and with isolated classical Hodgkin lymphoma by quantitative immunocytochemistry for mGluR5-expression. Further, we studied the L-1236, L-428, L-540, SUP-HD1, KM-H2, and HDLM-2 classical Hodgkin lymphoma cell lines by FACS and Western blot for mGluR5-expression, and by transcriptome analysis. mGluR5 surface expression differed significantly in terms of receptor density, distribution pattern, and percentage of positive cells. Highest expression levels were found in the L-1236 line. RNA-sequencing revealed more than 800 genes that were higher expressed in the L-1236 line in comparison to the other classical Hodgkin lymphoma cell lines. High mGluR5-expression was associated with upregulation of PI3K/AKT and MAPK pathways and of downstream targets (e.g. EGR1) known to be involved in classical Hodgkin lymphoma progression. Finally, mGluR5 expression was increased in the classical Hodgkin lymphoma-tissue of our Ophelia syndrome patient in contrast to five classical Hodgkin lymphoma-patients without autoimmune encephalitis. Given the association of encephalitis and classical Hodgkin lymphoma in Ophelia syndrome, it is possible that mGluR5-expression on classical Hodgkin lymphoma cells not only drives tumor progression but also triggers anti-mGluR5 encephalitis even before classical Hodgkin lymphoma becomes manifest.

Minigastrin (MG) analogs for therapy of CCK2R-expressing malignancies are limited by low stability in vivo or excessive accumulation in non-target organs. By modifying the C-terminal receptor-binding sequence, metabolization could be prevented and tumor targeting significantly improved. In this work, N-terminal changes of the peptide length were evaluated. Based on the amino acid sequence of DOTA-MGS5 (DOTA-DGlu-Ala-Tyr-Gly-Trp-(N-Me)Nle-Asp-1Nal-NH₂), two new MG analogs were synthesized, by either introduction of a penta-DGlu moiety or depletion of the four N-terminal amino acids and introduction of a non-charged hydrophilic linker. Two CCK2R-expressing cell lines were used to demonstrate receptor interaction. Stability of the ¹⁷⁷Lu-labeled peptide analogs was evaluated in human serum up to 24 h after incubation and in BALB/c mice up to 30 min after injection. The biodistribution profile and tumor targeting potential was evaluated in xenografted BALB/c nude mice. For both new MG analogs, the combination of strong receptor-specific cell interaction, high stability and enhanced tumor targeting could be demonstrated. Shortening of the peptide sequence lowered the absorption in the dose-limiting organs, whereas elongation increased uptake in renal tissue.

Ischemic stroke is one of the most disabling diseases and a leading cause of death globally. Despite advances in medical care, the global burden of stroke continues to grow, as no effective treatments to limit or reverse ischemic injury to the brain are available. However, recent preclinical findings have revealed the potential role of transient receptor potential cation 6 (TRPC6) channels as endogenous protectors of neuronal tissue. Activating TRPC6 in various cerebral ischemia models has been found to prevent neuronal death, whereas blocking TRPC6 enhances sensitivity to ischemia. Evidence has shown that Ca2+ influx through TRPC6 activates cAMP response element-binding protein (CREB), an important transcription factor linked to neuronal survival. Additionally, TRPC6 activation may counter excitotoxic damage resulting from glutamate release by attenuating the activity of NMDA receptors of neurons by posttranslational means. Unresolved though, are the roles of TRPC6 channels in non-neuronal cells such as astrocytes and endothelial cells. Moreover, TRPC6 channels may have detrimental effects on the blood-brain barrier, although their exact role in neurovascular coupling requires further investigation. This review discusses evidence-based cell-specific aspects of TRPC6 in the brain to assess the potential targets for ischemic stroke management.

Agaricus blazei Murrill or Himematsutake is an edible and medicinal mushroom. Agaricus blazei Murrill's fruiting body extracts have anticancer properties, although the mechanism is unknown. Basic or organic solvents, which are hazardous for human health, are generally used to prepare Agaricus blazei Murrill's extracts. Inhibition of immune checkpoint molecules and Axl receptor is an effective therapy in cancer. This study assessed whether subcritical water extracts of the Agaricus blazei Murrill's fruiting body or mycelium affect the expression of Axl and immune checkpoint molecules in lung cancer cells. We used A549 cells and mouse bone marrow-derived dendritic cells in the experiments. We prepared subcritical water extracts from the Agaricus blazei Murrill's fruiting body or mycelium. The subcritical water extracts from the Agaricus blazei Murrill's fruiting body or mycelium significantly inhibited the expression of immune checkpoint molecules and Axl compared to saline-treated cells. Also, the hot water extract, subcritical water extract, and the hot water extraction residue subcritical water extract from the Agaricus blazei Murrill's mycelium significantly enhanced the expression of maturation markers in dendritic cells. These observations suggest that the subcritical water extract from Agaricus blazei Murrill's mycelium is a promising therapeutic tool for stimulating the immune response in cancer.

We report the analysis of activation by corticosteroids and progesterone of full-length mineralocorticoid receptor (MR) from elephant shark, a cartilaginous fish belonging to the oldest group of jawed vertebrates. Based on their measured activities, aldosterone, cortisol, 11-deoxycorticosterone, corticosterone, 11-deoxcortisol, progesterone and 19-norprogesterone are potential physiological mineralocorticoids. However, aldosterone, the physiological mineralocorticoid in humans and other terrestrial vertebrates, is not found in cartilaginous or ray-finned fishes. Because progesterone is a precursor for corticosteroids that activate elephant shark MR, we propose that progesterone was an ancestral ligand for elephant shark MR. Although progesterone activates ray-finned fish MRs, progesterone does not activate human, amphibian or alligator MRs, suggesting that during the transition to terrestrial vertebrates, progesterone lost the ability to activate the MR. Comparison of RNA-sequence analysis of elephant shark MR with that of human MR suggests that MR expression in the human brain, heart, ovary, testis and other non-epithelial tissues evolved in cartilaginous fishes. Together, these data suggest that progesterone-activated MR may have unappreciated functions in elephant shark ovary and testis.

Imbalance in the oxidative status in neurons, along with mitochondrial damage, are common characteristics in some neurodegenerative diseases. The maintenance in energy production is crucial to face and recover from the oxidative damage and the coexistence of different sources of energy production, such as mitochondrial and glycolytic ATP, allows faster adaptative mechanisms to situations of high energy demand and may help in the maintenance of neuronal function in stress situations. Fingolimod phosphate is a drug with neuroprotective and antioxidant actions, used in the treatment of Multiple Sclerosis. This work has been performed in a model of oxidative damage on neuronal cell cultures exposed to menadione, in presence or absence of fingolimod phosphate. We have studied the mitochondrial function and several pathways related with glucose metabolism, including oxidative, glycolytic and pentose phosphate in neuronal cells cultures. Our results showed a beneficial effect on neuronal survival probably based in the recovery of all, oxidative balance, glycolysis and pentose phosphate, promoted by fingolimod phosphate. These effects are mediated, at least in part by the interaction with its specific receptor. These actions would make this drug a potential tool to the treatment of neurodegenerative processes, either to slow progression or alleviate symptoms.

Endotoxins are toxic substances that widely exist in the environment and can enter the intestine with food and other substances. Intestinal epithelial cells are protected by a mucus layer that contains MUC2 as its main structural component. However, a detailed understanding of the mechanisms involved in the function of the mucus barrier in endotoxin penetration is lacking. Here, we established the most suitable proportion of Caco-2/HT-29 co-culture cells as a powerful tool to evaluate the intestinal mucus layer. Our findings significantly advance current knowledge as focal adhesion and ECM-receptor interaction were identified as the two most significantly implicated pathways in MUC2 small interfering RNA (siRNA)-transfected Caco-2/HT-29 co-culture cells after 24 h of LPS stimulation. When the mucus layer was not intact, LPS was found to damage the tight junctions of Caco-2/HT29 co-cultured cells. Furthermore, LPS was demonstrated to inhibit the integrin-mediated focal adhesion structure and damage the matrix network structure of the extracellular and actin microfilament skeletons. Ultimately, LPS inhibited the interactive communication between the extracellular matrix and the cytoskeleton for 24 h in the siMUC2 group compared with the LPS(+) and LPS(-) groups. Overall, we recognized the potential of MUC2 as a tool for barrier function in several intestinal bacterial diseases.

The New World (NW) mammarenavirus group includes several zoonotic highly pathogenic viruses, such as Junin (JUNV) or Machupo (MACV). Contrary to Old World mammarenavirus, these viruses are not able to completely suppress the innate immune response, and trigger a robust interferon (IFN)-I response via retinoic acid-inducible gene I (RIG-I). Nevertheless, pathogenic NW mammarenaviruses trigger a weaker IFN response than their non-pathogenic relatives do. RIG-I activation leads to upregulation of a plethora of IFN-stimulated genes (ISGs), which exert a characteristic antiviral effect either as lone effectors, or resulting from the combination with other ISGs or cellular factors. The dsRNA sensor-protein kinase receptor (PKR) is an ISG that plays a pivotal role in the control of the mammarenavirus infection. In addition to its well-known protein synthesis inhibition, PKR further modulates the overall IFN-I response against different viruses, including mammarenaviruses. For this study, we employed Tacaribe virus (TCRV), the closest relative of the human pathogenic JUNV. Our findings indicate that PKR does not only increase IFN-I expression against TCRV infection, but also affects the kinetic expression and the extent of induction of Mx1 and ISG15 at both levels, mRNA and protein expression. Moreover, TCRV fails to prevent the effect of PKR on viral protein translation and its viral titer is inhibited when PKR is pre-stimulated via IFN-I. Here, we provide first evidence of the specific immunomodulatory role of PKR over selected ISGs, altering the dynamic of the innate immune response course against TCRV. IMPORTANCE: The mechanisms for innate immune evasion are key for emergence and adaptation of human pathogenic arenaviruses, and highly pathogenic mammarenaviruses such as JUNV or MACV trigger a weaker IFN response than non-pathogenic mammarenaviruses. Within the innate immune response context, PKR plays an important role in sensing and restricting the infection of TCRV virus. Although the mechanism of PKR for protein synthesis inhibition is well described, its immunomodulatory role is less understood. In this study, we found that TCRV protein expression and viral propagation are inhibited from early times after infection, and when externally activated, PKR inhibits TCRV viral progeny production. Our present findings further characterize the innate immune response in absence of PKR, unveiling the role of PKR in defining the ISG profile after viral infection.

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.

Chemotherapy represents the most applied approach to cancer treatment. Owing to the frequent onset of chemoresistance and tumor relapses, there is an urgent need to discover novel and more effective anticancer drugs. In search for therapeutic alternatives to treat the cancer disease, a se-ries of hybrid pyrazolo[3,4-d]pyrimidin-4(5H)-ones tethered with hydrazide-hydrazones, 5a-h, was synthesized from condensation reaction of pyrazolopyrimidinone-hydrazide 4 with a series of arylaldehydes in EtOH, in acid catalysis. In vitro assessment of antiproliferative effects against MCF-7 breast cancer cells, unveiled that 5a, 5e, 5g, and 5h were the most effective compounds of the series and exerted their cytotoxic activity through apoptosis induction and G0/G1 phase cell-cycle arrest. To explore their mechanism at a molecular level, 5a, 5e, 5g, and 5h were evalu-ated for their binding interactions with two well-known anticancer targets, namely the epider-mal growth factor receptor (EGFR) and the G-quadruplex DNA structures. Molecular docking simulations highlighted high binding affinity of 5a, 5e, 5g, and 5h towards EGFR. CD experi-ments suggested 5a as a stabilizer agent of the G-quadruplex from the KRAS oncogene promot-er. In the light of these findings, we propose the pyrazolo-pyrimidinone scaffold bearing a hy-drazide-hydrazone moiety as a lead skeleton for designing novel anticancer compounds.

Because of their low cost and easy production silica nanoparticles (NPs) are amply used in multiple manufactures as anti-caking, densifying and hydrophobic agents. However, this has increased the exposure levels of the general population and has raised concerns about possible toxicity of this nanomaterial. NPs are known to affect the function of the airway epithelium, but the biochemical pathways targeted by these particles remain largely unknown. Here we investigated the effects of NPs on the responses of cultured human bronchial epithelial (16HBE) cells to the damage-associated molecular pattern ATP, using fluorometric measurements of intracellular Ca2+ concentration. Upon stimulation with extracellular ATP these cells displayed a concentration-dependent increase in intracellular Ca2+, which was mediated by release from intracellular stores. Silica NPs inhibited the Ca2+ responses to ATP within minutes of application and at low micromolar concentrations, which are significantly faster and more potent than those previously reported for the induction of cellular toxicity and pro-inflammatory responses. NPs-induced inhibition appeared to be independent from the increase in intracellular Ca2+ they produce, and via a non-competitive mechanism. These findings suggest that NPs reduce the ability of airway epithelial cells to mount ATP-dependent protective responses such as the increase in mucociliary clearance and cough.

Lung cancer is the most common malignancy across the world. The new era in lung cancer treatments, especially this past decade, has yielded novel categories of targeted therapy for specific mutations and adjuvant therapy, both of which have led to improved survival rates. In the present study, we review the changes and development of treatments, with a special focus on adjuvant therapy using tyrosine kinase inhibitors (TKIs) administered to non-small-cell lung carcinoma patients who had a complete resection of the tumor harboring a mutated epidermal growth factor receptor. The clinical trials are dating from the past (chemotherapy trials), present (TKIs) and future (ongoing trials).

Migraine is a neurovascular disorder that affects approximately 12% of the global population. While its exact causes are still being studied, researchers believe that nociceptors in the trigeminal ganglia play a key role in the pain signals of migraine. These nociceptors innervate the intracranial meninges and convey pain signals from the meninges to the thalamus. Targeting these nociceptors is considered promising due to their accessibility and distinct molecular profile, which includes the expression of several transient receptor potential (TRP) channels. These channels have been linked to various pain conditions, including migraine. This review discusses the role and mechanisms of nociceptors in migraine, the challenges of current antimigraine drugs, and the evidence for well-studied and emerging TRP channels, particularly TRPC4, as novel targets for migraine prevention and treatment.

Epilepsy is characterized by repeated spontaneous reactions caused by hyper-excitability and neurons firing in high synchronization in the central nervous system. It seriously affects the quality of life of epileptic patients and nearly 30% of individuals are refractory to treatment of antiepileptic drugs. Therefore, there is an urgent need to develop new medicines to manage and control the refractory epilepsy. Cannabinoid ligands including selective cannabinoid receptor subtype (CB1 or CB2 receptor) ligands and non-selective cannabinoid (synthetic and endogenous) ligands may serve as the novel candidates for this need. Cannabinoid systems appear to regulating seizure activity in the brain through the activation of CB1 and CB2 cannabinoid receptors (CB1R and CB2R). An abundant series of cannabinoid analogues have been tested in various animal models, including a rat pilocarpine model of acquired epilepsy, in vitro hippocampal neuronal culture models of acquired epilepsy and status epilepticus, a pentylenetetrazole model of myoclonic seizures in mice and a penicillin-induced model of epileptiform activity in the rats. The accumulating lines of evidence show that cannabinoid ligands exhibit significant benefits to control seizure activity in different epileptic models. For this reason, we summarize the relationship between brain CB2 receptors and seizures, and emphasize the potential mechanisms of their therapeutic effects involving affecting neurons, astrocytes, and microglia cells. The unique features of CB2Rs, such as lower expression levels under physiological conditions and high inducibility under epileptic conditions, make it an important target for future research on drug-resistant epilepsy.

Up to 25% of early human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC) patients will relapse despite the improvement achieved by the introduction of HER2-targeted therapy. Beyond trastuzumab, other agents approved for early HER2+ BC include the monoclonal antibody pertuzumab, the antibody-drug conjugate (ADC) trastuzumab-emtansine (T-DM1) and the reversible HER2 inhibitor lapatinib. New agents, such as trastuzumab-deruxtecan or tucatinib in combination with capecitabine and trastuzumab, have also shown an improvement in the metastatic setting. Other therapeutic strategies to overcome treatment resistance have been explored in HER2+ BC, mainly in HER2+ that also overexpress estrogen receptors (ER+). One strategy has been to target the cyclin-dependent kinases 4/6 (CDK4/6) as they are downstream of HER2 and many of the cellular pathways associated with resistance to HER2-targeted therapies play a key role in cell cycle and proliferation. Different trials have explored these strategies with encouraging results, but definitive results are needed. In addition, HER2+ BC is known to be more immunogenic than other BC subgroups, with high variability between tumors. Different immunotherapeutic agents have been investigated in this setting, with promising but controversial results obtained to date.

The androgen/androgen receptor (AR)-signaling axis plays a central role in the development and growth of prostate cancer (PCa) cells. Upon androgen-binding the AR dimerizes with another AR, translocates into the nucleus where the AR-dimer activates/inactivates androgen-dependent genes. In consequence treatments for locally advanced or metastatic PCa are commonly based on androgen deprivation therapies (ADT). Unfortunately, the clinical benefits of ADT are only transitory and most tumors develop mechanisms allowing the AR to bypass its need for physiological levels of circulating androgens. In the clinic failure of ADT is often characterized by the synthesis of a C-terminally truncated, constitutively active AR splice variant, termed AR-V7. In contrast to AR, the constitutively active AR-V7 does no longer need androgenic stimuli for nuclear entry and/or dimerization. The goal of the present study was to mechanistically decipher the interaction between full-length AR (AR-FL) and AR-V7 in AR-null HEK-293 cells using the NanoLuc Binary Technology (NanoBiT) structural complementation assay under androgen stimulation and deprivation conditions. Our data point toward a hypothesis that AR-FL/AR-FL homodimers form in the cytoplasm, whereas AR-V7/AR-V7 localize in the nucleus. However, after 15 min of androgen stimulation, all AR-FL/AR-FL, AR-FL/AR-V7 and AR-V7/AR-V7 dimers localized in the nucleus. In this way, we can show an androgen-regulated interaction between AR-FL and AR-V7 at forming heterodimers that localize in the nucleus, whereas AR-V7/AR-V7 dimers were found to localize in the absence of androgens in the nucleus. Treatment with enzalutamide diminished the luminescence of AR-FL homodimers and AR-FL/AR-V7 heterodimers but not AR-V7/AR-V7 homodimers.

Background: We previously found that QNBC tumors are more frequent in African Americans compared to TNBC tumors. To characterize this subtype further, we sought to determine the miRNA-mRNA profile in QNBC patients based on race. Methods: Both miRNA and mRNA expression data were analyzed from TCGA and validated using datasets from the METABRIC, TCGA proteomic, and survival analysis by KMPLOT. Results: miRNA-mRNAs which include FOXA1 and MYC (mir-17/20a targets); GATA3 and CCNG2 (mir-135b targets); CDKN2A, CDK6, and B7-H3 (mir-29c targets); and RUNX3, KLF5, IL1-β, and CTNNB1 (mir-375 targets) were correlated with basal-like and immune subtypes in QNBC patients and associated with a worse survival. Conclusion: Thus, QNBC tumors have an altered gene signature implicated in racial disparity and poor survival.

Age-related macular degeneration is a progressive retinal disease that is associated with factors such as oxidative stress, decreased phagocytic activity, and inflammation. In this study, we evaluated the protective effects of SIG-1451, a non-steroidal anti-inflammatory drug developed for treating atopic dermatitis and known to inhibit toll-like receptor 4, on light-induced photoreceptor degeneration. SIG-1451 was intraperitoneally injected into rats once a day before exposure to 1000 lx light for 24 h; one day later, optical coherence tomography showed a decrease in retinal thickness, and electroretinogram (ERG) amplitude was also found to have decreased 3 d after light exposure. Moreover, SIG-1451 protected against this decrease in retinal thickness and increase in ERG am-plitude. One day after light exposure, upregulation of inflammatory response-related genes was observed, and SIG-1451 was found to inhibit this upregulation. Iba-1, a microglial marker, was suppressed in SIG-1451-injected rats. To investigate the molecular mechanism underlying these effects, we used lipopolysaccharide (LPS)-stimulated rat immortalised Müller cells. The upregu-lation of C-C motif chemokine 2　by LPS stimulation was significantly inhibited by SIG-1451 treatment, and western blot analysis revealed a decrease in phosphorylated I-κB levels. These results indicate that SIG-1451 protects photoreceptor cells by attenuating light damage progression through inhibiting inflammatory responses.

Dietary vitamin A/all-trans retinol/ROL plays a critical role in human vision. ROL circulates bound to the plasma retinol-binding protein (RBP4) as RBP4-ROL. In the eye, the STRA6 membrane receptor binds to circulatory RBP4 and internalizes ROL. STRA6 is however not expressed in systemic tissues, where there is high-affinity RBP4 binding and ROL uptake. We tested the hypothesis, that the second retinol-binding protein 4 receptor 2 (Rbpr2) which is highly expressed in systemic tissues of zebrafish and mouse, contains a functional RBP4 binding domain, critical for ROL transport. As for STRA6, modeling and docking studies confirmed three conserved RBP4 binding residues in zebrafish Rbpr2. In cell culture studies, disruption of the RBP4 binding residues on Rbpr2 almost completely abolished uptake of exogenous vitamin A. CRISPR generated rbpr2-RBP4 domain zebrafish mutants showed microphthalmia, shorter photoreceptor outer segments, and decreased opsins, that were attributed to impaired ocular retinoid content. Injection of WT-Rbpr2 mRNA into rbpr2 mutant or all-trans retinoic acid treatments rescued the mutant eye phenotypes. In conclusion, zebrafish Rbpr2 contains a putative extracellular RBP4-ROL ligand-binding domain, critical for yolk vitamin A transport to the eye for ocular retinoid production and homeostasis, for photoreceptor cell survival.

Transient receptor potential (TRP) channel family proteins are sensors for pain, which sense variety of thermal and noxious chemicals. Sensory neurons innervating the gut abundantly express TRPA1 and TRPV1 channels and are in close proximity of gut microbes. Emerging evidence indicates a bi-directional gut-brain cross-talk in several entero-neuronal pathologies; however, the direct evidence of TRP channels interacting with gut microbial populations is lacking. Herein, we examine whether and how the knockout (KO) of TRPA1 and TRPV1 channels individually or combined TRPA1/V1 double-knockout (dKO) impacts the gut microbiome in mice. We detect distinct microbiome clusters among the three KO mouse models versus wild-type (WT) mice. All three TRP-KO models have reduced microbial diversity, harbor higher abundance of Bacteroidetes, and reduced proportion of Firmicutes. Specifically distinct arrays in the KO models are determined mainly by S24-7, Bacteroidaceae, Clostridiales, Prevotellaceae, Helicobacteriaceae, Rikenellaceae, and Ruminococcaceae. A1KO mice have lower Prevotella, Desulfovibrio, Bacteroides, Helicobacter and higher Rikenellaceae and Tenericutes; V1KO mice demonstrate higher Ruminococcaceae, Lachnospiraceae, Ruminococcus, Desulfovibrio and Mucispirillum; while A1V1dKO mice exhibit higher Bacteroidetes, Bacteroides and S24-7 and lower Firmicutes, Ruminococcaceae, Oscillospira, Lactobacillus and Sutterella abundance. Also, the abundance of taxa involved in biosynthesis of lipids and primary and secondary bile acids is higher while that of fatty acid biosynthesis-associated taxa is lower in all KO groups. To our knowledge, this is the first study demonstrating distinct gut microbiome signatures in TRPA1, V1 and dKO models and should facilitate prospective studies exploring novel diagnostic/ therapeutic modalities regarding the pathophysiology of TRP channel proteins.

Trace amine-associated receptor 5 (TAAR5) is a G protein-coupled receptor that belongs to the TAARs family (TAAR1-TAAR9). TAAR5 is expressed in the olfactory epithelium and is responsible for sensing 3-methylamine (TMA). However, recent studies showed that TAAR5 is also expressed in the limbic brain regions and is involved in the regulation of emotional behaviour and adult neurogenesis, suggesting that TAAR5 antagonism may represent a novel therapeutic strategy for anxiety and depression. We used the AtomNet® model, the first deep learning neural network for structure-based drug discovery, to identify putative TAAR5 ligands and tested them in an in vitro BRET assay. We found two mTAAR5 antagonists with low to submicromolar activity that are able to inhibit the cAMP production induced by TMA. Moreover, these two compounds also inhibited the mTAAR5 downstream signalling, such as the phosphorylation of CREB and ERK. These two hits exhibit drug-like properties and could be used to develop further more potent TAAR5 ligands with putative anxiolytic and antidepressant activity.

Dystrophin-deficient cardiomyopathy (DDC) is currently the leading cause of death in patients with dystrophinopathies. Targeting myocardial fibrosis (MF) has become a major therapeutic goal in order to prevent the occurrence of DDC. We aimed to review and summarize the current evidence about the role of the renin-angiotensin-aldosterone system (RAAS) in the development and perpetuation of MF in DCC. We conducted a comprehensive search of peer-reviewed English literature on PubMed about this subject. We found increasing preclinical evidence from studies in animal models during the last 20 years pointing out a central role of RAAS in the development of MF in DDC. Local tissue RAAS acts directly mainly through its main fibrotic component angiotensin II (ANG2) and its transducer receptor (AT1R) and downstream TGF-b pathway. Also, it modulates the actions of most of the remaining pro-fibrotic factors involved in DDC. Despite limited clinical evidence, RAAS blockade constitutes the most studied, available and promising therapeutic strategy against MF and DDC. Conclusion: Based on the evidence reviewed, it would be recommendable to start RAAS blockade therapy through angiotensin converter enzyme inhibitors (ACEI) or AT1R blockers (ARBs) alone or in combination with mineralocorticoid receptor antagonists (MRa) at the youngest age after the diagnosis of dystrophinopathies, in order to delay the occurrence or slow the progression of MF, even before the detection of any cardiovascular alteration.

At the plasma membrane, transmembrane receptors are at the interface between cells and their environment. They allow sensing and transduction of chemical and mechanical extracellular signals. The spatial distribution of receptors and the specific recruitment of receptor subunits to the cell membrane is crucial for the regulation of signaling and cell behavior. However, it is challenging to define what regulates such spatial patterns for receptor localization, as cell shapes are extremely diverse when cells are maintained in standard culture conditions. Bone morphogenic protein receptors (BMPRs) are serine-threonine kinases, which build heteromeric complexes of BMPRI and II. These are especially interesting targets for receptor distribution studies, since the signaling pathways triggered by BMPR-complexes depends on their dimerization mode. They might exist as pre-formed complexes, or assemble upon binding of BMP, triggering cell signaling which leads to differentiation or migration. In this work we analyzed BMPR receptor distributions in single cells grown on micropatterns, which allows not only to control cell shape, but also the distribution of intracellular organelles and protein assemblies. We developed a script called ComRed (Center Of Mass Receptor Distribution), which uses center of mass calculations to analyze the shift and spread of receptor distributions according to the different cell shapes. ComRed was tested by simulating changes in experimental data, showing that shift and spread of distributions can be reliably detected. Our ComRed-based analysis of BMPR-complexes indicates that receptor distribution depends on cell polarization. The absence of a coordinated internalization after addition of BMP suggests that a rapid and continual recycling of BMPRs occurs. Receptor complexes formation and localization in cells induced by BMP might yield insights into the local regulation of different signaling pathways.

GPR4, a member of proton activated GPCRs group. Previously we have reported that GPR4 is constitutively active at physiological pH and knockout of GPR4 has shown to protect dopaminergic neuronal cells from caspase-dependent mitochondrial apoptotic cell death. In this study we have investigated the role of GPR4 in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) treated mice model of Parkinson’s disease. Subchronic administration of MPTP in mice produces oxidative stress induced apoptotic cell death of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and motor deficits. Treatment with NE52-QQ57, a selective antagonist of GPR4 reduced dopaminergic neuronal loss MPTP-intoxicated C57BL6/J mice and improved motor deficit and memory impairment. Co-treatment with NE52-QQ57 significantly decreases the protein level of proapoptotic marker (Bax), and increases the antiapoptotic marker (Bcl-2) in the SNpc and striatum tissue collected from the brain of MPTP inflicted mice. Further, MPTP induced activation of caspase 3 and cleavage of poly (ADP-ribose) polymerase (PARP) was significantly decreased in the SNpc and striatum tissue of NE52-QQ57 cotreated mice. Further mice receiving both MPTP and NE52-QQ57 mice showed significantly higher TH positive cells in the SNpc and striatum than MPTP treated mice alone. Moreover, NE52-QQ57 cotreatment improved the motor activity in the rotarod test and pole test and also improved spatial memory in Y maze test. Our findings suggest GPR4 as a potential therapeutic target for PD whereas the activation GPR4 is involved in the caspase mediated apoptotic cell death in SNpc and striatum of MPTP-intoxicated mice.

The natural product Salvinorin A (SalA) was the first nitrogen-lacking agonist discovered for the opioid receptors and exhibits high selectivity for the kappa opioid receptor (KOR) turning SalA into a promising analgesic to overcome the current opioid crisis. Since SalA’s suffers from poor pharmacokinetic properties, particularly the absence of gastrointestinal bioavailability, fast metabolic inactivation and subsequent short duration of action, the rational design of new tailored analogs with improved clinical usability is highly desired. Despite being known for decades, the binding mode of SalA within the KOR remains elusive as several conflicting binding modes of SalA were proposed hindering the rational design of new analgesics. In this study, we rationally determined the binding mode of SalA to the active state KOR by in silico experiments (docking, molecular dynamics simulations, dynophores) in the context of all available mutagenesis studies and structure-activity relationship (SAR) data. To the best of our knowledge this is the first comprehensive evaluation of SalA’s binding mode since the determination of the active state KOR crystal structure. SalA binds above the morphinan binding site with its furan pointing towards the intracellular core while the C2-acetoxy group is oriented towards the extracellular loop 2 (ECL2). SalA is solely stabilized within the binding pocket by hydrogen bonds (C210ECL2, Y3127.35, Y3137.36) and hydrophobic contacts (V1182.63, I1393.33, I2946.55, I3167.39). With the disruption of this interaction pattern or the establishment of additional interactions within the binding site we were able to rationalize the experimental data for selected analogs. We surmise the C2-substituent interactions as important for SalA and its analogs to be experimentally active, albeit moderate frequency within MD simulations of SalA. We further identified the non-conserved residues 2.63, 7.35, and 7.36 responsible for the KOR subtype selectivity of SalA. We are confident that the elucidation of the SalA binding mode will promote the understanding of KOR activation and the facilitate the development of novel analgesics that are urgently needed.

Trace amine-associated receptors (TAARs) are a family of G protein-coupled receptors present in mammals in the brain and in several peripheral organs. Apart from its olfactory role, TAAR5 is expressed in the major limbic brain areas and regulates brain serotonin functions and emotional behaviors. However, most of its functions remain undiscovered. Given the role of serotonin and limbic regions in some aspects of cognition, we used a temporal decision-making task to unveil a possible role of TAAR5 in cognitive processes. We found that TAAR5 knock-out (KO) mice showed a generally better performance due to a reduced number of errors and displayed a greater rate of improvement at the task than WT littermates. However, task-related parameters, such as time accuracy and uncertainty have not changed significantly. Overall, we show that TAAR5 modulates specific domains of cognition, highlighting a new role in brain physiology.

Kynurenic acid (KYNA) is an endogenous tryptophan (Trp) metabolite known to possess neuroprotective property. KYNA plays critical roles in nociception, neurodegeneration, and neuroinflammation. A lower level of KYNA is observed in patients with neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases or psychiatric disorders such as depression and autism spectrum disorders, whereas a higher level of KYNA is associated with the pathogenesis of schizophrenia. Little is known about the optimal concentration for neuroprotection and the threshold for neurotoxicity. In this study the effects of KYNA on memory functions were investigated by passive avoidance test in mice. Six different doses of KYNA were administered intracerebroventricularly to previously trained CFLP mice and they were observed following 24 hours. High doses of KYNA (i.e., 20-40 μg/2 μl) significantly decreased the avoidance latency, whereas a low dose of KYNA (0.5 μg/2 μl) significantly elevated it compared with controls, suggesting that the low dose of KYNA enhanced memory function. Furthermore, six different receptor blockers were applied to reveal the mechanisms underlying the memory enhancement induced by KYNA. The series of tests revealed the possible involvement of the serotonergic, dopaminergic, α and β adrenergic, and opiate systems in the nootropic effect. The study confirmed that a low dose of KYNA improved a memory component of cognitive domain, which was mediated by, at least in part, four systems of neurotransmission in an animal model of learning and memory.

Background and Aim. Since virus-related hepatocellular carcinoma (HCC) pathogenesis involves liver inflammation, therefore, post-hepatitis C virus (HCV) infection would be a cause for liver cirrhosis that would progress to HCC. Cytotoxic T cells (Tc) are known to be involved in post-HCV complications and HCC pathogenesis. The inhibitory checkpoint Leukocyte-Associated Immunoglobulin-like Receptor-1 (LAIR-1) is expressed on Tc. Therefore, we aimed to determine whether the Tc expression level of LAIR-1 is associated with HCC progression post-HCV and moreover, to evaluate LAIR-1 expression as a non-invasive biomarker for HCC progression in the context of liver cirrhosis post-HCV genotype 4 (G4) in Egyptian patients’ peripheral venous blood liquid biopsy. We studied LAIR-1 expression on Tc related to the progression of liver cirrhosis in a case-controlled study enrolled 64 patients with post-HCV G4-HCC and 37 patients with post-HCV G4-liver cirrhosis. Methods: LAIR-1 expression was analyzed by flow cytometry. Results: LAIR-1 expression on Tc and the percentage of Tc positive for LAIR-1 (LAIR-1+Tc %) were significantly higher in the post-HCV G4-HCC group compared to the post-HCV G4-liver cirrhosis

ATP and other nucleoside phosphates have specific receptors named purinergic receptors. Purinergic receptors and ectonucleotidases regulate various signaling pathways that play a role in physiological and pathological processes. Extracellular ATP in the tumor microenvironment (TME) has a higher level than in normal tissues and plays a role in cancer cell growth, survival, angiogenesis, metastasis, and drug resistance. In this review, we investigated the role of purinergic receptors in the development of resistance to therapy through changes in tumor cell metabolism. When a cell transforms to neoplasia, its metabolic processes change. The metabolic reprogramming modified metabolic feature of the TME, that can cause impeding immune surveillance and promote cancer growth. The purinergic receptors contribute to therapy resistance by modifying cancer cells' glucose, lipid, and amino acid metabolism. Limiting the energy supply of cancer cells is one approach to overcoming resistance. Glycolysis inhibitors which reduce intracellular ATP levels, may make cancer cells more susceptible to anti-cancer therapies. The loss of the P2X7R through glucose intolerance and decreased fatty acid metabolism reduces therapeutic resistance. Potential metabolic blockers that can be employed in combination with other therapies will aid in the discovery of new anti-cancer immunotherapy to overcome therapy resistance. Therefore, therapeutic interventions that are considered to inhibit cancer cell metabolism and purinergic receptors simultaneously can potentially reduce resistance to treatment.

Abstract Forensic institutions throughout the country house patients with severe psychiatric illness and history of criminal violations. Improved medical care, hygiene, and nutrition led to unmatched longevity in this population which previously lived on average 15 to 20 years shorter than the public at large. On the other hand, longevity has contributed to increased prevalence of age-related diseases, including neurodegenerative disorders, which complicate clinical management. Forensic institutions, originally intended for the treatment of younger individuals, are ill-equipped for the growing number of older offenders. Moreover, as antipsychotic drugs became available in 1950s and 1960s, we are observing the first generation of forensic detainees who had aged on dopamine blockers. Although the consequences of long-term treatment with these agents are unclear, schizophrenia-associated gray matter loss, may contribute to the development of early dementia. Taken together, increased lifespan and subsequent cognitive deficit observed in long-term psychiatric institutions brought forth questions and dilemmas unencountered by the previous generations of clinicians, such as: 1. Does the presence of neurocognitive dysfunction justify antipsychotic dose reduction or discontinuation despite a lifelong history of schizophrenia and violent behavior? 2. Should neurolipidomic interventions become the standard of care in elderly individuals with lifelong schizophrenia and dementia? 3. Can patients with schizophrenia and dementia meet the Dusky standard and stand trial? 4. Should neurocognitive disorders in elderly with lifelong schizophrenia be treated differently than age-related neurodegeneration? In this article, we describe strategies for potentially slowing the development of neurocognitive disorders in forensic patients with chronic mental illness by adopting a three-prong strategy: 1. Approaching lifelong psychosis from microbial and immunological perspective. 2. Identify modifiable risk factors for age-related diseases in forensic institutions. 3. Utilizing novel receptor-independent treatments for chronic psychosis.

Superoxide, a form of reactive oxygen species (ROS), is catabolized by superoxide dismutase (SOD) and contributes to carcinogenesis via the oxidative damage it inflicts on cells. The aim of this research was to analyze the potential vitamin D-mediated regulation of the antioxidative “SOD1-to-SOD2 switch” within the human MG-63 osteosarcoma model. For this study; real-time PCR analysis was performed using MG-63 cells exposed to metabolically active 1,25(OH)₂D₃. Frist; a sustained statistically significant >2-fold suppression of proliferating cell nuclear antigen (PCNA) transcripts was observed after 10nM but not at 100nM of 1,25(OH)₂D₃ treatment; suggesting a cytostatic effect. In order to assess regulators of mitochondrial oxidative phosphorylation; gene expression of COX2 and COX4l1 of the mitochondrial complex IV and antioxidative enzymes (SOD1; SOD2 and Catalase (CAT)) were monitored. For COX2 and COX4l1; no changes in gene expression were observed. However; a concomitant decrease in CAT and SOD1 mRNA; and increase in SOD2 mRNA after 24 hours of 10nM 1,25(OH)₂D₃ treatment were observed. A ~8-fold increase in SOD2 mRNA was apparent after 48 hours. The significant increase in SOD2 activity in the presence of vitamin D indicates an antioxidant potential and sensitization of vitamin D during osteosarcoma transformation and mitochondrial detoxification over time.

Even brief epileptic seizures can lead to activity-dependent structural remodeling of neural circuitry. Animal models show that the functional plasticity of synapses and changes in the intrinsic excitability of neurons can be crucial for epileptogenesis. However, the exact mechanisms underlying epileptogenesis remain unclear. We induced epileptiform activity in rat hippocampal slices for 15 min using a 4-aminopyridine (4-AP) in vitro model and observed hippocampal hyperexcitability for at least 1 hour. We tested several possible mechanisms of this hyperexcitability, including changes in intrinsic membrane properties of neurons, presynaptic and postsynaptic alterations. Neither input resistance nor other essential biophysical properties of hippocampal CA1 pyramidal neurons were affected by epileptiform activity. The glutamate release probability also remained unchanged, as the frequency of miniature EPSCs and the paired amplitude ratio of evoked responses did not change after epileptiform activity. However, we found an increase in the AMPA/NMDA ratio, suggesting alterations in the properties of postsynaptic glutamatergic receptors. Thus, the increase in excitability of hippocampal neural networks is realized through postsynaptic mechanisms. In contrast, the intrinsic membrane properties of neurons and the probability of glutamate release from presynaptic terminals are not affected in a 4-AP model.

HepG2 cells reconstituted with Hepatitis B virus (HBV) entry receptor sodium taurocholate co-transporting polypeptide (NTCP) are widely used as a convenient in vitro cell culture infection model for HBV replication studies. As such, it is pertinent that HBV infectivity is maintained at steady-state levels for accurate interpretation of in vitro data. However, variations in HBV infection efficiency due to imbalanced NTCP expression levels in the HepG2 cell line may affect experimental results. In this study, we performed single cell cloning of HepG2-NTCP-A3 parental cells via limiting dilution and obtained multiple subclones with increased permissiveness to HBV. Specifically, one subclone (HepG2-NTCP-A3/C2) yielded more than 4-fold higher HBV infection compared to the HepG2-NTCP-A3 parental clone. In addition, though HBV infectivity was universally reduced in the absence of polyethylene glycol (PEG), subclone C2 maintained relatively greater permissiveness under PEG-free conditions, suggesting the functional heterogeneity within parental HepG2-NTCP-A3 may be exploitable in developing a PEG-free HBV infection model. The increased viral production correlated with increased intracellular viral antigen expression as evidenced through HBcAg immunofluorescence staining. Further, these subclones were found to express different levels of NTCP, albeit with no remarkable morphology or cell growth differences. In conclusion, we isolated subclones of HepG2-NTCP-A3 which support efficient HBV production and thus provide an improved in vitro HBV infection model.

Two histamine receptor subtypes (HR), namely H1R and H4R, as key components, are involved in the transmission of histamine-induced itch. Although exact downstream signaling mechanisms are still elusive, transient receptor potential (TRP) ion channels play important roles in the sensation of histaminergic and non-histaminergic itch. Aim of this study was to investigate the involvement of TRPV1 and TRPA1 channels in the transmission of histaminergic itch. The potential of TRPV1 and TRPA1 inhibitors to modulate H1R- and H4R-induced signal transmission was tested in a scratching assay in mice in vivo and in vitro via Ca2+ imaging of murine sensory dorsal root ganglia (DRG) neurons. The TRPV1 inhibition led to a reduction of H1R- and H4R- induced itch and reduced Ca2+ influx into the neurons. The TRPA1 inhibitor reduced H4R-induced itch and both H1R- and H4R-induced Ca2+ influx. In conclusion, these results indicate that both channels, TRPV1 and TRPA1 are involved in the transmission of histamine-induced pruritus.

Modern oncological therapy utilizes various types of immunotherapy. Immune checkpoint inhib-itors (ICIs), chimeric antigen receptor T cells (CAR-T) therapy, cancer vaccines and bispecific an-tibodies are improving patients’ outcomes. However, stimulation of the immune system, benefi-cial in terms of fighting against cancer, generates the risk of harm to other cells in a patient's body. Kidney damage belongs to the relatively rare adverse events (AEs). Best described, but still, su-perficially, are renal AEs in patients treated with ICIs. International guidelines issued by Euro-pean Society for Medical Oncology (ESMO) and American Society of Clinical Oncology (ASCO) cover the management of immune-related adverse events (irAEs) during ICI therapy. There are scarce data concerning renal adverse drug reactions of other immunotherapeutic methods. This implicates the need for the collection of safety data during ongoing clinical trials and in the re-al-life world to characterize the hazard related to the use of new immunotherapies and manage-ment of irAEs.

The objective of the present study is to isolate phages targeting multidrug resistant (MDR), extended spectrum beta lactamase (ESBL) positive clinical isolate of E. coli ( U1007), sequence and analyze the phage genome and use machine learning tools to predict host cell surface receptor and finally evaluate the efficiency of monophage and phage cocktail in vitro and in vivo in a zebrafish model. Phage specific for E. coli U1007 was isolated from Ganges River (designated as U1G), Cuoom River (designated as CR) and Hospital waste water (designated as M phage). The obtained phages were triple purified and enriched. U1G phages had a greater burst size of 124 PFU/cell and a latent time of 25 min.M phage had a burst size of 150 PFU/cell with a shortlatent time of 20min. Similarly CR phage has a short latent 20 min and a burst size of 115 PFU/cell. Based on capsid architecture, U1G phage resembles Podoviridae, CR phage is structurally similar to Myoviridae and M phage has morphology that resembles Siphoviridae. Genome sequencing and analysis revealed that the size of the U1G phage genome is 73275 bp Whereas that of CR phage and M phage are 45236 bp and 45294 bp, respectively. All three genomes were marked by the absence of genes encoding tRNA sequence, antibiotic resistant or virulent genes. A machine learning (ML) based multi-class classification model using algorithms such as Random Forest, Logistic Regression, and Decision Tree were employed to predict the host receptor targeted by all 3 phages and the best performing algorithm Random Forest predicted LPS O antigen , LamB or OmpC for U1G FhuA, OmpC for CR phage and FhuA, LamB, TonB or OmpF for the M phage as the host receptor targeted by the receptor binding protein (RBP) of the phages. In vitro time kill assay showed that treatment with monophages alone and along with colistin resulted in regrowth whereas phage combinations significantly reduced the regrowth and by 24h the phage cocktail along with colistin produced a significant 3 log declinein cell counts relative to the untreated control. In vivo intramuscular infection study in zebrafish showed that phages were non toxic and a cocktail of dual (U1G +M) phage along with colsitin resulted in a significant 3.5 log decline in cell counts whereas triple phage combination along with colistin resulted in 3 log decline in cell counts probably due to host receptor competition. Our study highlights the potential of phage cocktail therapy in mitigating MDR clinical isolate of E. coli in vitro and in vivo.

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.

KDEL receptor-1 maintains homeostasis in the early secretory pathway by capturing and retrieving ER-chaperones to the ER during heavy secretory activity. We have previously shown that a Golgi scaffolding protein (ACBD3) facilitates KDEL receptor localization at the Golgi via regulating cargo wave-induced cAMP/PKA-dependent signaling pathway. Unexpectedly, a fraction of the receptor is also known to reside in the plasma membrane as a stress response, although it is largely unknown exactly how KDEL receptor gets exported from the Golgi and travels to the PM. In this study, we sought to investigate the mechanism by which KDEL receptor gets exported from the Golgi en route to the PM and identified two crucial factors that greatly influence post-Golgi trafficking of KDEL receptor. We show here that ACBD3 depletion results in significantly increased trafficking of KDEL receptor to the PM via Rab4-positive tubular carriers emanating from the Golgi. Expression of constitutively activated Rab4 mutant (Q72L) increases surface expression of KDEL receptor up to 2~3-fold, whereas expression of GDP-locked Rab4 mutant (S27N) inhibits KDEL receptor localization to the PM. Importantly, KDELR trafficking from the Golgi to the PM is independent of PKA- and Src Kinase-mediated mechanism. Taken together, these results reveal that ACBD3 and Rab4-GTP are key players at the Golgi in regulating KDEL receptor trafficking to the cell surface.

The involvement of the angiotensin II type 1 receptor in the Frank-Starling Law of the Heart, where the various activations are very limited, allows simple analysis of the kinase systems involved and thence extrapolation of the mechanism to that of angiotensin control of activation of cardiac and skeletal muscle contraction. The involvement of phosphorylation of the myosin light chain in the control of contraction is accepted but not fully understood. The involvement of troponin-I phosphorylation is also indicated but of unknown mechanism. There is no known signal for activation of myosin light chain kinase or Protein Kinase C-βII other than Ca²⁺/calmodulin but the former is constitutively active and thus has to be under control of a regulated inhibitor, the latter kinase may also be the same. Ca²⁺/calmodulin is not activated in Frank-Starling, i.e. there are no diastolic or systolic [Ca²⁺] changes. I suggest here that that the regulated inhibition is by myosin light chain phosphatase and/or β-arrestin. Angiotensin activation is by translocation of the β-arrestin from the sarcoplasm to the PM thus reducing its kinase inhibition action in the sarcoplasm, this reduced inhibition has been wrongly attributed to a mythical downstream agonist property of β-arrestin.

The effect of the antioxidant vitamin C in cancer has been studied for over 30 years with conflict-ing results ranging from total absence of effect, to possible protective effect, to potential therapeutic effect when administered in high doses. The aim of the study was to define the effect of vitamin C in breast cancer and the possible involvement of sphingomyelin metabolism. Therefore, the effect of low and high dose of vitamin C on cells reproducing luminal A type (MCF7) and triple negative type (MB231) of breast cancer was analyzed. The results showed that high dose of vitamin C produced effects only in MCF7 cells such as decreased cell viability, modulation of cell cycle re-lated genes, unexpected change in cell phenotype due to estrogen receptor downregulation, catabo-lism of sphingomyelin with a large increase in ceramide. In conclusion, we demonstrated that high doses of VitC on the one hand reduce the growth of lu-minal A type breast cancer cells and on the other hand induce their phenotypic change towards hormone therapy resistant cells. The effect of vitamin C on therapeutic treatment failure of luminal A breast cancer and the possible involvement of high ceramide levels were discussed.

The progesterone receptor (PR) mediates progesterone regulation of female reproductive physiology, as well as gene transcription in non-reproductive tissues, such as brain, bone, lung and vasculature, in both women and men. An unusual property of progesterone is its high affinity for the mineralocorticoid receptor (MR), which regulates electrolyte transport in the kidney in humans and other terrestrial vertebrates. In humans, rats, alligators and frogs, progesterone antagonizes activation of the MR by aldosterone, the physiological mineralocorticoid in terrestrial vertebrates. In contrast, in elephant shark, ray-finned fishes and chickens, progesterone activates the MR. Interestingly, cartilaginous fishes and ray-finned fishes do not synthesize aldosterone, raising the question of which steroid(s) activate the MR in cartilaginous fishes and ray-finned fishes. The simpler synthesis of progesterone, compared to cortisol and other corticosteroids, makes progesterone a candidate physiological activator of the MR in elephant sharks and ray-finned fishes. Elephant shark and ray-finned fish MRs are expressed in diverse tissues, including heart, brain and lung, as well as, ovary and testis, two reproductive tissues that are targets for progesterone, which together suggests a multi-faceted physiological role for progesterone activation of the MR in elephant shark and ray-finned fish. The functional consequences of progesterone as an antagonist of some terrestrial vertebrate MRs and as an agonist of fish and chicken MRs are not fully understood. Indeed, little is known of physiological activities of progesterone via any vertebrate MR.

Since 2000, caffeine is used as citrate salt of caffeine for treatment of apnea of prematurity. However, it remained elusive if caffeine citrate has a direct function in the respiratory epithelium, potentially as modulator for ciliary beat frequency (CBF) regulation in human respiratory cells (hRECs). Here, we studied the mechanism of action of caffeine citrate on the respiratory epithelium on hRECs derived from healthy donors and individuals with cystic fibrosis (CF) cultured under air-liquid-interface (ALI) conditions. CBF analyses of hRECs were performed by high-speed video microscopy. In the presence of caffeine, hRECs show a significant increase in CBF over ciliary base frequency (CBFb), demonstrating a direct influence of caffeine on ciliary function. We also demonstrate a specific action of caffeine at ryanodine receptor (RYR) channels, mediating calcium efflux from intracellular stores to increase CBF. We describe a novel pharmacological effect of caffeine citrate - direct increase of CBF of primary hRECs cultured at ALI. Caffeine citrate has certain advantages over other methylxanthines: it was shown to have stable plasma concentration, longer half-life, and is better tolerated than e.g. theophylline. We conclude that caffeine citrate therapy might be suitable strategy to treat respiratory diseases with compromised mucociliary clearance.