Receptor Modulators Research Articles

P-367 Letrozole or Tamoxifen co-administration during fertility preservation of breast cancer patients: a retrospective cohort study

Abstract Study question How do fertility preservation (FP) outcomes differ between breast cancer patients stimulated with FSH and Tamoxifen versus FSH and Letrozole? Summary answer Letrozole and Tamoxifen co-administration yielded similar number of retrieved and cryopreserved oocytes/embryos, as well as similar oocyte maturation and fertilization and rates. What is known already Oocyte/embryo cryopreservation is recommended before initiation of chemotherapy in cancer patients. The co-administration of Tamoxifen, a selective estrogen receptor modulator, or Letrozole, an aromatase inhibitor, during ovarian stimulation with gonadotropins, are used to limit the potentially harmful effects of a supra-physiological rise in estrogen levels on hormone-sensitive cancers. However, the optimal choice between the two is still unclear and with no sound evidence. Study design, size, duration Retrospective cohort study of all FP treatments of newly diagnosed breast cancer patients in two tertiary centers between 2000-2022. Collected data included 354 FP cycles of 290 patients and compared treatment parameters and outcomes of Tamoxifen or Letrozole co-administration. Participants/materials, setting, methods Breast cancer patients who underwent FP before chemotherapy were included. Patients with a history of radiation or gonadotoxic treatment, as well as those undergoing other fertility preservation treatments, such as ovarian tissue cryopreservation were excluded. Main results and the role of chance Overall, 215 Letrozole and 139 Tamoxifen treatment cycles were compared, with no significant demographic differences. Treatments with Letrozole had higher FSH dosages (3970IU vs. 2839IU, p < 0.001) but shorter duration (9.7 vs. 10.5 days, p < 0.001). The Letrozole group achieved lower peak E2 levels and endometrial thickness (1508pmol/L, 8.1mm vs. 8760pmol/L, 9.5mm, p < 0.001). The mean number of retrieved oocytes was comparable between the groups (13.6 with Letrozole vs 14.7 with Tamoxifen, p = 0.06). In 122 Letrozole and 46 Tamoxifen patients that underwent strictly oocytes cryopreservation the mean number of cryopreserved oocytes was comparable (11 vs. 12.1, p = 0.21). Moreover, in embryo cryopreservation cycles of 71 patients treated with Letrozole compared to 76 patients with Tamoxifen, no difference was observed in the number of cryopreserved embryos (6.2 vs. 7.0, p = 0.12). Oocyte maturation rate among strictly oocyte preservation cycles was comparable (86% with Letrozole vs. 83% with Tamoxifen, p = 0.80), as were fertilization rates in embryo cryopreservation cycles (62% vs. 63%, p = 0.8 and 71% vs. 76%, p = 0.3 in IVF and ICSI with Letrozole and Tamoxifen, respectively). Multivariate analysis, controlling for potential confounders showed no significant correlations between Tamoxifen or Letrozole co-administration and the number of retrieved oocytes or oocyte maturation rate. Limitations, reasons for caution The primary limitation of our study is its retrospective design and the variation in treatment duration and gonadotrophin dosages among groups. Wider implications of the findings This study provides reassurance that both Tamoxifen and Letrozole are equally effective options when co-administered in FP treatments of breast cancer patients. Trial registration number not applicable

Review of AlphaFold 3: Transformative Advances in Drug Design and Therapeutics.

Google DeepMind Technologies Limited (London, United Kingdom) recently released its new version of the biomolecular structure predictor artificial intelligence (AI) model named AlphaFold 3. Superior in accuracy and more powerful than its predecessor AlphaFold 2, this innovation has astonished the world with its capacity and speed. It takes humans years to determine the structure of various proteins and how the shape works with the receptors but AlphaFold 3 predicts the same structure in seconds. The version's utility is unimaginable in the field of drug discoveries, vaccines, enzymatic processes, and determining the rate and effect of different biological processes. AlphaFold 3 uses similar machine learning and deep learning models such as Gemini (Google DeepMind Technologies Limited). AlphaFold 3 has already established itself as a turning point in the field of computational biochemistry and drug development along with receptor modulation and biomolecular development. With the help of AlphaFold 3 and models similar to this, researchers will gain unparalleled insights into the structural dynamics of proteins and their interactions, opening up new avenues for scientists and doctors to exploit for the benefit of the patient. The integration of AI models like AlphaFold 3, bolstered by rigorous validation against high-standard research publications, is set to catalyze further innovations and offer a glimpse into the future of biomedicine.

Discovery of Potent, Orally Bioavailable Sphingosine-1-Phosphate Transporter (Spns2) Inhibitors.

Targeting the S1P pathway has resulted in the development of S1P1 receptor modulators for the treatment of multiple sclerosis and ulcerative colitis. We hypothesize that targeting an upstream node of the S1P pathway may provide an improved adverse event profile. In this report, we performed a structure-activity relationship study focusing on the benzoxazole scaffold in SLB1122168, which lead to the discovery of 11i (SLF80821178) as a potent inhibitor of S1P release from HeLa cells (IC50: 51 ± 3 nM). Administration of SLF80821178 to mice induced ∼50% reduction in circulating lymphocyte counts, recapitulating the lymphopenia characteristic of Spns2 null animals. Molecular modeling studies suggest that SLF80821178 binds Spns2 in its occluded inward-facing state and forms hydrogen bonds with Asn112 and Ser211 and π stacking with Phe234. Taken together, SLF80821178 can serve as a scaffold for future inhibitor development and represents a chemical tool to study the therapeutic implication of inhibiting Spns2.

Clinical effectiveness of coronavirus disease 2019 vaccination in patients with multiple sclerosis stratified by disease-modifying treatment.

Coronavirus disease 2019 (COVID-19) vaccination has been associated with a dampened humoral and/or cellular immune response in patients with multiple sclerosis (MS) who were concurrently on disease-modifying treatment (DMT) with B-cell depleting agents or sphingosine-1-phosphate receptor modulators (S1PRMs). Our main goal was to investigate the impact of these DMT classes on the clinical effectiveness of COVID-19 vaccination. Since March 2020, demographics and clinical data of patients with MS who developed COVID-19 have been collected at the Belgian National MS Centre in Melsbroek. Patients were considered to be 'protected by vaccination' if they were (i) fully vaccinated and (ii) tested positive for COVID-19 in the period ranging from 14 days to 6 months after the last administered vaccine. On 19 December 2022, 418 COVID-19 cases were retrospectively identified in 389 individual patients. Hospitalization and mortality rates resulting from the infection were 10.8% and 2.4%, respectively. Being 'unprotected by vaccination' was significantly associated with a worse COVID-19 outcome (i.e., hospitalization and/or death) in the total cohort (N = 418, odds ratio [OR] 3.96), in patients on ongoing DMT other than anti-CD20 agents or S1PRMs (N = 123, OR 31.75) and in patients without DMT (N = 182, OR 5.60), but not in those receiving anti-CD20 agents (N = 91, OR 0.39); the S1PRMs subgroup was considered too small (22 infections) for any meaningful analysis. Coronavirus disease 2019 vaccination protects against severe infection in patients with MS but it was not possible to confirm this effect in those on DMT with B-cell depleting agents.

Discovery of a mu-opioid receptor modulator that in combination with morphinan antagonists induces analgesia.

Morphinan antagonists, which block opioid effects at mu-opioid receptors, have been studied for their analgesic potential. Previous studies have suggested that these antagonists elicit analgesia with fewer adverse effects in the presence of the mutant mu-opioid receptor (MOR; S196A). However, introducing a mutant receptor for medical applications represents significant challenges. We hypothesize that binding a chemical compound to the MOR may elicit a comparable effect to the S196A mutation. Through high-throughput screening and structure-activity relationship studies, we identified a modulator, 4-(2-(4-fluorophenyl)-4-oxothiazolidin-3-yl)-3-methylbenzoic acid (BPRMU191), which confers agonistic properties to small-molecule morphinan antagonists, which induce G protein-dependent MOR activation. Co-application of BPRMU191 and morphinan antagonists resulted in MOR-dependent analgesia with diminished side effects, including gastrointestinal dysfunction, antinociceptive tolerance, and physical and psychological dependence. Combining BPRMU191 and morphinan antagonists could serve as a potential therapeutic strategy for severe pain with reduced adverse effects and provide an avenue for studying G protein-coupled receptor modulation.

Development and validation of stability-indicating method of etrasimod by HPLC/DAD/MS/MS technique with greenness profiling

Etrasimod, a novel selective sphingosine-1-phosphate receptor modulator, was recently approved by the U.S. Food and Drug Administration and the European Medicinal Agency for the treatment of moderately to severely active ulcerative colitis in adults. In this research, the forced degradation study as an integral part of drug product and packaging development, which generates data on degradation mechanisms, is published. The development and validation of the stability-indicating method using a superior high-performance liquid chromatography technique coupled with a diode array detector and tandem mass spectrometer was performed to support the forced degradation study and monitor the formation of degradation products. Etrasimod demonstrated good stability under elevated temperature and basic stress conditions, while acidic hydrolysis, oxidative, and photolytic degradation produced eight degradation products. The knowledge of degradation products will be useful in the long-term stability study for establishing the acceptance criteria of etrasimod as a drug substance and dosage form during quality control and stability assessment. The eco-friendliness of the developed forced degradation procedure was evaluated using various greenness appraisal tools. The green metric tools showed that the forced degradation procedure obeys eco-friendly conditions.

Positive Allosteric Modulation of NMDARs Prevents the Altered Surface Dynamics Caused by Patients' Antibodies.

A positive allosteric modulator of the NMDAR, SGE-301, has been shown to reverse the alterations caused by the antibodies of patients with anti-NMDAR encephalitis (NMDARe). However, the mechanisms involved beyond receptor modulation are unclear. In this study, we aimed to investigate how this modulator affects NMDAR membrane dynamics. Cultured hippocampal neurons were treated with SGE-301 or vehicle, alongside with immunoglobulins G (IgG) from patients with NMDARe or healthy controls. NMDAR surface dynamics were assessed with single-molecule imaging by photoactivated localization microscopy. NMDAR trajectories from neurons treated with SGE-301 were less confinement, with increased diffusion coefficients. This effect mainly occurred at synapses because extrasynaptic diffusion and confinement were minimally affected by SGE-301. Treatment with patients' IgG reduced NMDAR surface dynamics and increased their confinement. Remarkably, SGE-301 incubation antagonized patients' IgG effects in both synaptic and extrasynaptic membrane compartments, restoring diffusion and confinement values similar to those from neurons exposed to control IgG. We demonstrate that SGE-301 upregulates NMDAR surface diffusion and antagonizes the pathogenic effects of patients' IgG on NMDAR membrane organization. These findings suggest a potential therapeutic strategy for NMDARe.

Positive Allosteric Modulation of GABAA α5 Receptors Improves Memory performance of rats with Conditions of Hippocampal Hyperactivity

Positive Allosteric Modulation of GABAA α5 Receptors Improves Memory performance of rats with Conditions of Hippocampal Hyperactivity

Neuroprotective efficacy of the glucocorticoid receptor modulator PT150 in the rotenone mouse model of Parkinson’s disease

Parkinson's disease (PD) is the most common neurodegenerative movement disorder worldwide. Current treatments for PD largely center around dopamine replacement therapies and fail to prevent the progression of pathology, underscoring the need for neuroprotective interventions. Approaches that target neuroinflammation, which occurs prior to dopaminergic neuron (DAn) loss in the substantia nigra (SN), represent a promising therapeutic strategy. The glucocorticoid receptor (GR) has been implicated in the neuropathology of PD and modulates numerous neuroinflammatory signaling pathways in the brain. Therefore, we investigated the neuroprotective effects of the novel GR modulator, PT150, in the rotenone mouse model of PD, postulating that inhibition of glial inflammation would protect DAn and reduce accumulation of neurotoxic misfolded ⍺-synuclein protein. C57Bl/6 mice were exposed to 2.5 mg/kg/day rotenone by intraperitoneal injection for 14 days. Upon completion of rotenone dosing, mice were orally treated at day 15 with 30 mg/kg/day or 100 mg/kg/day PT150 in the 14-day post-lesioning incubation period, during which the majority of DAn loss and α-synuclein (α-syn) accumulation occurs. Our results indicate that treatment with PT150 reduced both loss of DAn and microgliosis in the nigrostriatal pathway. Although morphologic features of astrogliosis were not attenuated, PT150 treatment promoted potentially neuroprotective activity in these cells, including increased phagocytosis of hyperphosphorylated α-syn. Ultimately, PT150 treatment reduced the loss of DAn cell bodies in the SN, but not the striatum, and prohibited intra-neuronal accumulation of α-syn. Together, these data indicate that PT150 effectively reduced SN pathology in the rotenone mouse model of PD.

Endoscopic, Histologic, and Composite Endpoints in Patients With Ulcerative Colitis Treated With Etrasimod

Histologic remission, a potentially important treatment target in ulcerative colitis (UC), is associated with favorable long-term outcomes. Etrasimod is an oral, once-daily, selective sphingosine 1-phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active UC. This post-hoc analysis of the ELEVATE UC program evaluated the efficacy of etrasimod according to histologic and composite (histologic/endoscopic/symptomatic) endpoints and examined their prognostic value. Patients with moderately to severely active UC were randomized 2:1 to once-daily oral etrasimod 2 mg or placebo. Histologic and composite endpoints, including disease clearance (endoscopic/histologic/symptomatic remission), were assessed at Weeks 12 (ELEVATE UC 52; ELEVATE UC 12) and 52 (ELEVATE UC 52). Logistic regressions examined associations between baseline and Week 12 histologic/composite endpoints and Week 52 outcomes. At Weeks 12 and 52, significant improvements with etrasimod vs placebo were observed in histologic/composite outcomes, including endoscopic improvement-histologic remission and disease clearance. The proportion of patients treated with etrasimod achieving clinical remission at Week 52 was higher among those with disease clearance at Week 12 vs those without disease clearance (73.9% [17/23] vs 28.3% [71/251]). Histologic improvement and endoscopic improvement at Week 12 were moderately and strongly associated with clinical remission at Week 52 (odds ratio [OR], 2.37; 95% confidence interval [CI], 1.27-4.41; and OR, 6.36; 95% CI, 3.47-11.64, respectively). Histologic remission and endoscopic improvement at Week 12 were strongly associated with endoscopic improvement-histologic remission at Week 52 (OR, 3.21; 95% CI, 1.70-6.06 and OR, 5.47; 95% CI, 2.89-10.36, respectively). Etrasimod was superior to placebo for achievement of stringent histologic and composite endpoints. gov, Number: NCT03945188; ClinicalTrials.gov, Number: NCT03996369.

Nongenomic ERα-AMPK Signaling Regulates Sex-Dependent Bcrp Transport Activity at the Blood-Brain Barrier.

The blood-brain barrier (BBB) is an extensive capillary network that protects the brain from environmental and metabolic toxins while limiting drug delivery to the central nervous system (CNS). The ATP-binding cassette transporter breast cancer resistance protein (Bcrp) reduces drug delivery across the BBB by actively transporting its clinical substrates back into peripheral circulation before their entry into the CNS compartment. 17β-Estradiol (E2)-elicited changes in Bcrp transport activity and expression have been documented previously. We report a novel signaling mechanism by which E2 decreases Bcrp transport activity in mouse brain capillaries via rapid nongenomic signaling through estrogen receptor α. We extended this finding to investigate the effects of different endocrine-disrupting compounds (EDCs) and selective estrogen receptor modulators (SERMs) on Bcrp transport function. We also demonstrate sex-dependent expression of Bcrp and E2-sensitive Bcrp transport activity at the BBB ex vivo. This work establishes an explanted tissue-based model by which to interrogate EDCs and SERMs as modulators of nongenomic estrogenic signaling with implications for sex and hormonal regulation of therapeutic delivery into the CNS.

Recent advances in treatment of prurigo nodularis

Abstract Prurigo nodularis is a chronic skin condition which has significant negative impacts on the psychosocial function and quality of life of affected patients. It is a heterogeneous disease with complex underlying pathogenic mechanisms, and the clinical efficacy of traditional treatment options is often limited. Recently, great advances have been made in the pathogenesis of prurigo nodularis, which have enabled the development of novel targeted therapies for this disease. Various clinical trials have investigated the therapeutic efficacy of biologics which target the Th2 pathway. Dupilumab, a monoclonal antibody targeting interleukin 4 (IL-4) receptor α, has shown clinical efficacy and obtained United States Food and Drug Administration approval for prurigo nodularis. In addition, nemolizumab (IL-31 receptor A antagonist) and vixarelimab (oncostatin M receptor β antagonist) have shown therapeutic efficacy in clinical trials for prurigo nodularis. Small-molecule inhibitors with clinical promise which are currently under investigation include nalbuphine (opioid receptor modulator), Janus kinase inhibitors, and aprepitant and serlopitant (neurokinin-1 receptor antagonists). The recent development of new biologics and small-molecule inhibitors targeting various immunological and neurological signaling pathways have provided great hope that we are entering a new era of targeted therapies for this challenging clinical condition. In addition, recent advances in RNA sequencing technology may enable the identification of unique signaling pathways and the development of novel treatments for this disease in the future. In this review article, we summarize the current knowledge of the pathogenesis of prurigo nodularis, and discuss recent advances in treatment for this challenging clinical condition.

Flagellin Restricts HIV-1 Infection of Macrophages through Modulation of Viral Entry Receptors and CC Chemokines.

Both bacteria product flagellin and macrophages are implicated in HIV-1 infection/disease progression. However, the impact of their interaction on HIV-1 infection and the associated mechanisms remain to be determined. We thus examined the effect of the flagellins on HIV-1 infection of primary human macrophages. We observed that the pretreatment of macrophages with the flagellins from the different bacteria significantly inhibited HIV-1 infection. The mechanistic investigation showed that the flagellin treatment of macrophages downregulated the major HIV-1 entry receptors (CD4 and CCR5) and upregulated the CC chemokines (MIP-1α, MIP-1β and RANTES), the ligands of CCR5. These effects of the flagellin could be compromised by a toll-like receptor 5 (TLR5) antagonist. Given the important role of flagellin as a vaccine adjuvant in TLR5 activation-mediated immune regulation and in HIV-1 infection of macrophages, future investigations are necessary to determine the in vivo impact of flagellin-TLR5 interaction on macrophage-mediated innate immunity against HIV-1 infection and the effectiveness of flagellin adjuvant-based vaccines studies.

Indigo Naturalis in Inflammatory Bowel Disease: mechanisms of action and insights from clinical trials.

This study investigates the therapeutic potential of Indigo Naturalis (IN) in treating a Inflammatory Bowel Disease (IBD). The objective is to comprehensively examine the effects and pharmacological mechanisms of IN on IBD, assessing its potential as an novel treatment for IBD. Analysis of 11 selected papers is conducted to understand the effects of IN, focusing on compounds like indirubin, isatin, indigo, and tryptanthrin. This study evaluates their impact on Disease Activity Index (DAI) score, colon length, mucosal damage, and macrophage infiltration in Dextran Sulfate Sodium (DSS)-induced colitis mice. Additionally, It investigate into the anti-inflammatory mechanisms, including Aryl hydrocarbon Receptor (AhR) pathway activation, Nuclear Factor kappa B (NF-κB)/nod-like receptor family pyrin domain containing 3 (NLRP3)/Interleukin 1 beta (IL-1β) inhibition, and modulation of Toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MYD88)/NF-κB and Mitogen Activated Protein Kinase (MAPK) pathways. Immunomodulatory effects on T helper 17 (Th17)/regulatory T cell (Treg cell) balance and Glycogen synthase kinase-3 beta (GSK3-β) expression are also explored. Furthermore, the study addresses the role of IN in restoring intestinal microbiota diversity, reducing pathogenic bacteria, and increasing beneficial bacteria. The findings reveal that IN, particularly indirubin and indigo, demonstrates significant improvements in DAI score, colon length, mucosal damage, and macrophage infiltration in DSS-induced colitis mice. The anti-inflammatory effects are attributed to the activation of the AhR pathway, inhibition of inflammatory pathways, and modulation of immune responses. These results exhibit the potential of IN in IBD treatment. Notably, the restoration of intestinal microbiota diversity and balance further supports its efficacy. IN emerges as a promising and effective treatment for IBD, demonstrating anti-inflammatory effects and positive outcomes in preclinical studies. However, potential side effects necessitate further investigation for safe therapeutic development. The study underscores the need for future research to explore a broader range of active ingredients in IN to enhance therapeutic efficacy and safety.

The Impact of Phaleria macrocarpa Fruit Flavonoid Extract on Endometrial Thickness in Mice Menopausal Model

This study aims to determine how the effect of flavonoid phaleria macrocarpa fruit extract on the endometrial thickness of Mus musculus which is used as an experimental animal with a menopause model. This study employed a randomized post-test-only control group design on 32 female mice. Ovariectomy simulated menopause, followed by treatment with flavonoid from Phaleria macrocarpa fruit extract. Post-observariectomized, follicle-stimulating hormone levels indicated menopausal status. Hematoxylin-Eosin methods assessed endometrial thickness. The result indicated reduced endometrial thinning in the positive control group (K+). Conversely, the treatment group (P1-P4) exhibited increased endometrial thickness post-flavonoid extract administration. Ovariectomized-induced estrogen decline resulted in reduced endometrial thinning, mimicking menopausal conditions. Statistically, flavonoid extract administration increased endometrial thickness in ovariectomized-induced menopausal mice, with optimal effect observed at 7.5 mg/mice/day for 14 days. The preferred intervention dose for altering endometrial thickness in menopausal conditions was identified as P1 (3.75 mg/mice/day). In conclusion, a flavonoid from Phaleria macrocarpa fruit extract mitigates endometrial thinning in the menopausal mice model. For implication in menopausal women, clinical trials need to be conducted to evaluate the dosage of these flavonoids for their potential as a natural SERM (Selective Estrogen Receptor Modulator) before clinical application in managing endometrial health. Additionally, research on molecular effects particularly regarding ER (Estrogen Receptors) in the endometrial organ, is needed to confirm their phytoestrogenic effect.

Molecular Docking and Dynamics Studies of Withania somnifera Derived Compounds as GABA-A Receptor Modulators for Insomnia

Objective: This study aimed to identify potential phytochemicals from <i>Withania somnifera</i> (ashwagandha) that can act as gamma-aminobutyric acid A (GABA-A) receptor agonists or stimulant, and evaluate their suitability as potential insomnia treatments. Methods: Various computational approaches were employed, including virtual screening, biological activity prediction, physicochemical and drug-likeness analysis, absorption, distribution, metabolism, excretion, and toxicity (ADME/T) analysis, and molecular dynamics simulations. The Diseases Plants Eliminate (DISPEL) server was used to identify suitable plant species in context to insomnia, and the Indian Medicinal Plants, Phytochemistry And Therapeutics 2.0 (IMPPAT 2.0) database was utilized to assess the phytochemicals from <i>W. somnifera</i>. Virtual screening was performed using AutoDock Vina, and biological activity prediction was carried out using the Prediction of Activity Spectra for Substances (PASS) web server. The SwissADME webserver was used for physicochemical and drug-likeness analysis, while the ADME/T analysis was conducted using the ADMETlab 2.0 and ProTox 3.0 servers. Molecular dynamics simulations were performed using the WEBGRO Macromolecular Simulations server. Results: The findings revealed that hygrine, tropine, and withasomnine exhibited promising GABA-A receptor agonist activity, favorable drug-likeness properties, low toxicity, and stable receptor-ligand interactions. These phytochemicals demonstrated desirable physiochemical properties, adhering to Lipinski’s rule of five, and exhibited favorable ADME profiles. Molecular dynamics simulations showed stable interactions between the compounds and the GABA-A receptor, with minimal conformational changes and high compactness observed for hygrine and tropine. Conclusion: The phytochemicals hygrine, tropine, and withasomnine from <i>W. somnifera</i> emerged as potential lead compounds for the development of novel insomnia treatments targeting the GABA-A receptor. These findings warrant further investigation through experimental validation and optimization to advance their development as potential therapeutic agents for insomnia.

Allosteric modulators of M1 muscarinic receptors enhance acetylcholine efficacy and decrease locomotor activity and turning behaviors in zebrafish

Allosteric modulation of muscarinic acetylcholine receptors (mAChR) has been identified as a potential strategy for regulating cholinergic signaling in the treatment of various neurological disorders. Most positive allosteric modulators (PAMs) of mAChR enhance agonist affinity and potency, while very few PAMs (e.g., amiodarone) selectively enhance G protein coupling efficacy. The key structural features of amiodarone responsible for enhancement of mAChR efficacy were examined in CHO cells expressing M1 receptors. Subsequent incorporation of these structural features into previously identified allosteric modulators of potency (i.e., n-benzyl isatins) generated ligands that demonstrated similar or better enhancement of mAChR efficacy, lower in vivo toxicity, and higher allosteric binding affinity relative to amiodarone. Notable ligands include 8a, c which respectively demonstrated the strongest binding affinity and the most robust enhancement of mAChR efficacy as calculated from an allosteric operational model. Amiodarone derivatives and hybrid ligands were additionally screened in wildtype zebrafish (Danio rerio) to provide preliminary in vivo toxicity data as well as to observe effects on locomotor and turning behaviors relative to other mAChR PAMs. Several compounds, including 8a, c, reduced locomotor activity and increased measures of turning behaviors in zebrafish, suggesting that allosteric modulation of muscarinic receptor efficacy might be useful in the treatment of repetitive behaviors associated with autism spectrum disorder (ASD) and other neuropsychiatric disorders.

Aryl Hydrocarbon Receptor Modulation and Resveratrol Influence on Dnah1 Expression: Implications for Male Reproductive Health

Male reproductive health is intricately regulated by molecular and physiological processes, with the aryl hydrocarbon receptor (AhR) playing a crucial role. AhR is activated by various ligands and influences the onset and progression of diseases. The aim of this study was to evaluate the role of AhR on spermatogenesis in adult male rats were affected by resveratrol (RES) and CH223191, an AhR antagonist. The study include forty rats were randomly divided into four equal groups: Control group, DMSO group, RES group and AhR‾ group, the rats received respective treatments intraperitoneally twice weekly for 60 days, and various parameters related to male reproductive health were evaluated. The AhR that activation by the RES treatment were enhanced the sperm morphology, sperm acrosomal integrity and luteinizing hormone. Moreover, the Dnah1 gene expression, is has play major role in sperm morphology, was upregulated and testosterone levels were elevated by RES. On the other hand, sperm morphology, sperm acrosomal integrity, testosterone hormone levels, and Dnah1 expression were all reduced in AhR‍ rats. The testicular tissue integrity was maintained by RES, according to a histopathological analysis. These findings highlight the role of AhR in male reproductive health and suggest RES as a potential therapeutic agent.

Enhancing cognitive recovery in chronic traumatic brain injury through simultaneous allosteric modulation of α7 nicotinic acetylcholine and α5 GABAA receptors

Traumatic brain injury (TBI) leads to changes in the neural circuitry of the hippocampus that result in chronic learning and memory deficits. However, effective therapeutic strategies to ameliorate these chronic learning and memory impairments after TBI are limited. Two pharmacological targets for enhancing cognition are nicotinic acetylcholine receptors (nAChRs) and GABAA receptors (GABAARs), both of which regulate hippocampal network activity to form declarative memories. A promising compound, 522–054, both allosterically enhances α7 nAChRs and inhibits α5 subunit-containing GABAARs. Administration of 522–054 enhances long-term potentiation (LTP) and cognitive functioning in non-injured animals. In this study, we assessed the effects of 522–054 on hippocampal synaptic plasticity and learning and memory deficits in the chronic post-TBI recovery period. Adult male Sprague Dawley rats received moderate parasagittal fluid-percussion brain injury or sham surgery. At 12 wk after injury, we assessed basal synaptic transmission and LTP at the Schaffer collateral-CA1 synapse of the hippocampus. Bath application of 522–054 to hippocampal slices reduced deficits in basal synaptic transmission and recovered TBI-induced impairments in LTP. Moreover, treatment of animals with 522–054 at 12 wk post-TBI improved cue and contextual fear memory and water maze acquisition and retention without a measurable effect on cortical or hippocampal atrophy. These results suggest that dual allosteric modulation of α7 nAChR and α5 GABAAR signaling may be a potential therapy for treating cognitive deficits during chronic recovery from TBI.

The role of α7nAchR and PD-L1 in neuroimmune regulation of keloid treatment

Keloid formation, characterized by aberrant fibroproliferation and immune dysregulation, remains a challenging clinical concern. This study aims to elucidate the neuroimmune mechanisms underlying keloid pathogenesis and explores the efficacy of a combined treatment approach involving modulation of the α7 nicotinic acetylcholine receptor (α7nAchR), a key player in neural transmission, and programmed death ligand 1 (PD-L1), an immune checkpoint molecule, for keloid intervention. A key innovation lies in the identification of signal peptide-CUB-EGF-like domain-containing protein 3 (SCUBE3) as a potential target gene influenced by this dual treatment. We elucidate the underlying mechanism, wherein the hypoxic keloid microenvironment fosters an upsurge in SCUBE3 secretion. Subsequently, SCUBE3 forms complexes with TGF-β, initiating the activation of the PI3K/AKT/NF-κB signaling pathway. Notably, SCUBE3 is secreted in the form of exosomes, thereby exerting a profound influence on the differentiation of T cells and macrophages within the keloid milieu. This research not only provides a comprehensive understanding of the molecular mechanisms involved but also offers a promising avenue for the development of targeted therapies to address keloid-associated fibrosis and immune dysregulation. In conclusion, the combined inhibition of α7nAchR and PD-L1 represents a promising therapeutic strategy with SCUBE3 as a pivotal molecular target in the complex landscape of keloid pathophysiology.