Insulin secretion from pancreatic β-cells is controlled by multiple mechanisms, including metabolic, electrophysiological, and second-messenger pathways. To identify insulinotropic small molecules, we performed in silico similarity screening using zatebradine, an HCN-channel ligand, as a structural query and functionally evaluated 26 hit compounds. Compound 2 showed the strongest insulinotropic activity and was used to synthesize the novel compound MDC134. MDC134 enhanced insulin secretion in MIN6-K8 cells and isolated mouse islets under stimulatory glucose conditions. MDC134 enhanced insulin secretion in isolated mouse islets and showed a tendency to increase insulin secretion in isolated non-diabetic human islets. Under high-glucose conditions, MDC134 increased intracellular Ca[2+] levels, and nifedipine abolished its insulinotropic effect, indicating the involvement of voltage-dependent L-type Ca[2+] channel-mediated Ca[2+] influx. MDC134 also increased cellular cAMP content, although less potently than GLP-1. MDC134 treatment did not clearly affect glucose tolerance in C57BL/6J or ob/ob mice but significantly suppressed glucose elevation in β-cell-specific Kcnj11 knockout mice. These findings identify MDC134 as a novel glucose-dependent insulinotropic small molecule that enhances β-cell insulin secretion through Ca[2+] influx and cAMP-associated amplification, and suggest that it may be useful for therapeutic strategies for diabetes characterized by impaired insulin secretion.

Synthetic polymers play a crucial role in enhancing the performance of drug formulations by enabling controlled release, improving bioavailability, and ensuring stability. Copovidone is frequently employed as an excipient in hot-melt extrusion (HME) to augment the solubility of active pharmaceutical ingredients (APIs). However, this method faces two significant challenges: identifying the optimal copovidone/API composition (the solubility of the crystalline API in the copovidone matrix) and the inadequate time-dependent stability of some amorphous APIs in the copovidone matrix. To overcome these issues, it's crucial to accurately assess the solubility and miscibility of the crystalline drug within the polymer, which is essential for developing a stable polymer/API amorphous system. This study utilized Plasdone[™] S630 Ultra copovidone, a widely used solubility enhancer, to solubilize the poorly water-soluble active pharmaceutical ingredient (API) nifedipine. Several amorphous copovidone/nifedipine extrudates with drug loadings ranging from 10 to 60% w/w were produced via HME at temperatures above nifedipine's melting point to optimize the copovidone/API ratio for stability and homogeneity. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) measurements confirmed that all extrudates were amorphous regardless of drug loading (even at 60% w/w), as indicated by the presence of a single glass transition temperature and broad diffraction patterns. The extrudate stability and homogeneity were evaluated through a heat-cool temperature cycle using a rheometer. At lower drug loads, the extrudates exhibited homogeneity with consistent rheological behavior during the rheological temperature cycles. Medium drug loads led to slight rheological deviations, indicating a heterogeneous structure with API-rich areas. In contrast, high drug loads exhibited larger changes in rheological properties, likely indicating the dynamic formation of API nuclei. Although all extrudates exhibited enhanced solubility compared to their crystalline forms, those with higher drug loading showed poor physical stability, as evidenced by API recrystallization during accelerated-condition storage. In conclusion, this designed rheological study helps formulation scientists determine the optimal polymer/API composition (semi-phase diagram). This diagram and subsequent stability tests reveal that thermodynamic stability depends on the formulation composition, underscoring the importance of determining the API's solubility in the polymer.

Dehydroepiandrosterone (DHEA) is an adrenal steroid hormone that serves as a precursor to androgens and estrogens and participates in several physiological processes. Its levels naturally decline with age, and reduced DHEA concentrations have been associated with an increased risk of cardiovascular disease. However, this relationship is complex, and further research is required to clarify whether DHEA supplementation may help to prevent age-related vascular dysfunction. Here, we investigated the vascular effects of DHEA using mouse aorta and bovine aortic endothelial cells (BAEC), focusing on the potential involvement of hydrogen sulfide (H2S). DHEA exhibited a more pronounced vasorelaxant effect in endothelium intact aortas, mediated not only by nitric oxide (NO) but also by H2S. A significant increase in H2S production was observed following incubation of the aorta with DHEA compared to the vehicle. In addition to H2S, the involvement of L-type calcium channels in DHEA-induced vasorelaxation was found. Nifedipine, an inhibitor of L-type calcium channels, significantly reduced DHEA-induced vasorelaxation, and vice versa, suggesting a shared target. Consistent with the aortic findings, an increase in NO formation was observed in BAEC exposed to DHEA. Using two complementary approaches, we further demonstrate that DHEA enhanced H2S production in BAEC, with effects persisting for up to 2 h. Collectively, these findings suggest that DHEA promotes vasodilation through dual NO- and H2S-dependent pathways, along with modulation of L-type calcium channels. Our data provide new insights into the mechanisms of action of DHEA, supporting its protective role in the vasculature.

Introduction Calcium channel blockers (CCBs), particularly amlodipine, are among the most widely prescribed antihypertensive agents globally. However, no comprehensive disproportionality analysis has quantified this association. This pharmacovigilance study utilized the FDA Adverse Event Reporting System (FAERS) to evaluate the reporting association between CCBs and pseudolymphoma. Methods The FAERS database was parsed through its 14,104,743 adverse event reports. Five CCBs were evaluated: three dihydropyridines (amlodipine, nifedipine, felodipine) and two non-dihydropyridines (diltiazem, verapamil). Disproportionality was quantified using reporting odds ratios. The MedDRA preferred term "pseudolymphoma" was employed for case identification. Results Among 319 pseudolymphoma reports, 44 were associated with dihydropyridines and 1 with non-dihydropyridines. Amlodipine demonstrated the strongest signal (ROR 38.08, 95% CI 27.60-52.54; n=42), followed by nifedipine (ROR 18.61, 95% CI 4.64-74.74; n=2). Diltiazem showed a non-significant signal (ROR 5.47, 95% CI 0.77-38.93; n=1). Felodipine and verapamil yielded no reports. Dihydropyridines exhibited 7- to 70-fold greater reporting odds ratios compared with non-dihydropyridines. Conclusions This analysis establishes a robust, though not causal, class-specific safety signal linking dihydropyridine CCBs, particularly amlodipine, to pseudolymphoma risk. The substantial disproportionality suggests a pharmacologically mediated mechanism requiring heightened clinical surveillance, prompt recognition, and timely drug discontinuation to prevent potential malignant transformation.

During metastasis, circulating tumor cells (CTCs) are subjected to fluidic shear stress (SS), which eliminates many of them but paradoxically enhances malignancy and metastatic success. Meanwhile, given the critical roles of reactive oxygen species (ROS) in stress response and cancer, we engineer a circulation-mimicking microfluidic system which generates pulsatile SS to investigate the interplay among SS, ROS and metastasis. A 3-hour SS treatment rapidly elevates ROS levels, boosting metastatic abilities in triple-negative breast cancer (TNBC) cells in vitro and in vivo. RNA-sequencing and subsequent investigation identify activator protein-1 (AP-1) transcription factor members FOS, ATF3 and FOSB, which undergo dramatic ROS-dependent increase and nuclear localization upon SS stimulation. All three genes exhibit metastasis-promoting potential, while FOS displays the strongest ability to trigger distant lung metastasis in an orthotopic tumor model and correlates with worse clinical outcomes. Mechanistically, calcium channel acts as the mechano-sensor to initiate the SS-ROS cascade, with calcium channel blockers Mibefradil and Nifedipine effectively weakening SS-ROS-induced invasiveness. Following ROS elevation, the downstream activation of p38-ELK1-cFOS and JNK-cJUN pathways subsequently increase the expression of malignancy-related genes. This metastasis-promoting SS-calcium channel-ROS-FOS axis provides new insights for combating metastatic progression in breast cancer.

This study aimed to investigate the non-genomic effect of testosterone (T) on uterine muscle contractility in non-pregnant and 22nd day pregnant rats, in vivo. It provides the first evidence of an in vivo T uterine relaxation effect during pregnancy. Circulating T levels were measured within 8 hours after a single intraperitoneal (ip) administration of T (10 mg/kg) by ELISA. The kinetic curves of a single dose of T (10 mg/kg of ip) were estimated for 8 hours; plasma T was measured using ELISA kits. The rapid in vivo action of T was studied by measuring contractions using strain-gauge sensors in 15-minute intervals, and the AUC was calculated. The animals received T alone (3/10/30/100/300 mg/kg ip), with flutamide (100 mg/kg ip), solvent (DMSO+Macrogol 25% + 75%, 1 ml/kg ip) or normal saline (1 ml/kg) (n = 5-8/group, 160-220 g). To verify the possible mechanism of action, we also examined the uterine relaxing effect of T (10-4 M) and nifedipine (10-7 M) in vitro on KCl (40 mM)-stimulated contractions by cumulatively increasing the concentration of CaCl2 (1-120 mM) in the organ bath. Plasma T and 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) levels were measured by ELISA before and 30-minutes after administration (n = 4-8/group, 200-220 g). T had similar half-life and tmax values in both non-pregnant and pregnant rats, however, the AUC values were higher in pregnant animals. T (30/100/300 mg/kg single ip dose) elicited a flutamide-resistant dose-dependent uterine relaxing effect in both non-pregnant and 22nd day pregnant rats. T plasma levels were proportional with the administered doses. 4-HPPD plasma levels remained unchanged in both non-pregnant and 22nd day pregnant rats after 30 min of T administration. A single dose T induces rapid, non-genomic, dose-dependent uterine relaxation via blocking of calcium effect in non-pregnant and late-pregnant rats in vivo. Based on our results, T or its analogues might be good candidates for further pre-clinical and clinical studies for uterine hyperactivity-related conditions.

High-Grade Serous Ovarian Cancer (HGSOC) is the most lethal gynecological malignancy due to aggressive growth, widespread metastases, and high intra-tumoral heterogeneity. Poor prognosis is largely due to late diagnosis, hence there is an urgent need to identify novel biomarkers for screening, diagnosis, and monitoring. Here, we propose the voltage-dependent calcium channel hCaV1.2 encoded by CACNA1C as a potential biomarker and therapeutic target in HGSOC. Using IHC analysis for ten ovarian cancer patients, cytotoxicity assay, TCGA gene expression and survival analyses, homology modeling, molecular docking, Calcium channel membrane assembly and molecular dynamics simulations, we tested CACNA1C's role in HGSOC progression and the effect of blocking on cancer cell survival. We show that nifedipine (NIFE), a calcium channel blocker (CCB), had a tumor suppressive effect based on binding models predicted by three-dimensional computer assisted molecular modeling and in vitro validation using human HGSOC cell line. Using The Cancer Genome Atlas ovarian public cohort, we found CACNA1C mRNA expression strongly correlated with poor patient survival for late-stage and metastasis than primary. We also show strong correlation of CACNA1C protein expression using immunohistochemistry correlating with COH ovarian carcinomas patients' disease progression. This research demonstrates that targeting HGSOC via CCBs may be therapeutically beneficial. By establishing further in vitro, in vivo, and clinical trials using FDA approved NIFE may be repurposed to target CACNA1C for HGSOC.

Background: Amorphous drug formulations are commonly used to improve the solubility and bioavailability of poorly soluble molecular pharmaceuticals, yet less is known about their molecular conformations and local bonding interactions than their crystalline phases. Methods: High-energy X-ray diffraction structure factor measurements have been made on liquid and glassy nifedipine (NIF), felodipine (FEL), NIF 1:3 polyvinylpyrrolidone (PVP), and FEL 1:3 PVP wt.% mixtures. The corresponding X-ray pair distribution functions have been interpreted using empirical potential structure refinement using different models and density functional theory conformer calculations. Results: In both NIF and FEL, the NH···O inter-molecular hydrogen bonds between the pyridyl nitrogen and ester carbonyls are found to be considerably weaker than those observed in the crystalline polymorphs. For nifedipine, it is proposed that either inter-molecular NH…ON nitro bonds are present and/or a fraction (<20%) of conformational changes, with the aryl ring flipped, occur in the liquid state. For felodipine, the models indicate significant disorder associated with the methyl and ethyl side chains in the liquid state, with the main peak intensity at 3.0 Å arising from intra-molecular Cl-Cl atom pairs. When nifedipine molecules are incorporated into PVP, our models show they possess stronger NH···O bonds to the PVP polymer than felodipine molecules, which have stronger affinity for bonding to the polymer than to other felodipine molecules. Conclusions: The amorphous forms of both NIF and FEL show much weaker hydrogen bonding than found in their crystalline phases. Liquid NIF also exhibits configurations which are not observed in the crystal phases.

Objectives: As widely used first-line antihypertensive drugs, dihydropyridine calcium channel blockers (DHP-CCBs) have relatively few studies comparing their adverse reactions based on real-world data. This study aims to identify and compare the potential adverse drug reaction (ADR) signals of four DHP-CCBs (amlodipine, felodipine, nicardipine, and nifedipine) through the US Food and Drug Administration Adverse Event Reporting System (FAERS), providing a reference for further drug safety assessment and clinical medication risk awareness. Methods: Adverse event reports from medical professionals (Q3 2014-Q4 2024) were analyzed using signal detection methods, including reporting odds ratio (ROR), proportional reporting ratio (PRR), information component (IC), and the Medicines and Healthcare Products Regulatory Agency (MHRA) methods. Risk signals for the four DHP-CCBs were compared with both the full database and the DHP-CCBs background. For high-risk signals in amlodipine, multivariate logistic regression was used for validation. The analysis reveals distinct ADR profiles for the four DHP-CCBs. Results: Amlodipine is strongly linked to suicide-related risks, confirmed by logistic regression. Nicardipine and nifedipine show significant risks for pregnancy-related events, such as premature delivery and exposure during pregnancy. Nicardipine is also associated with hyponatremia, hyperkalemia, and lactic acidosis. These adverse events are not yet included in the FDA labeling for any of the DHP-CCBs. Although palpitations and angioedema are listed for felodipine, their signal strength is much higher compared to the other DHP-CCBs. Conclusions: The ADR risk profiles of the four DHP-CCBs differ significantly. This study identified several high-risk adverse events not included in current labels. Clinical use should consider each drug's risk profile and patient-specific factors, with particular attention to serious risk signals. For pregnant and postpartum women, the benefits and risks of using nicardipine and nifedipine should be carefully evaluated.

Context-induced relapse is a major barrier to recovery from alcohol use disorder (AUD). Identifying molecular targets involved in contextual memories associated with alcohol use may serve as novel pharmacotherapies. Our RNAseq profiling study of the hippocampus from rhesus monkeys with chronic alcohol use identified the voltage-gated calcium channel CACNA1C as a promising therapeutic target. However, data regarding CACNA1C expression in AUD and whether inhibition of CACNA1C can attenuate ethanol contextual memories remains limited. We tested the hypothesis that hippocampal CACNA1C expression is increased in human and nonhuman primates (NHPs) with chronic alcohol use. Further, we used a mouse conditioned place preference (CPP) paradigm to test the hypothesis that Nifedipine, a CACNA1C-selective L-type calcium channel antagonist, can attenuate ethanol-induced CPP. CACNA1C mRNA expression was increased in the hippocampus of subjects with AUD (p < 0.03). Increased densities of CACNA1C neurons (p < 0.01) and glia (p < 0.02) were observed in rhesus monkeys with chronic alcohol use. Ethanol-treated mice spent more time in the ethanol-paired chamber compared to the vehicle animals (p < 0.04), demonstrating ethanol-induced CPP. This effect was attenuated by Nifedipine, as time spent in the ethanol-paired chamber in the ethanol + Nifedipine group was not significantly different from the vehicle group. These findings demonstrate that chronic alcohol use increases CACNA1C expression in the hippocampus across species and that a CACNA1C subtype-selective antagonist reduces ethanol-induced CPP. Together, these results support CACNA1C as a promising therapeutic target for memory dysfunction in AUD.