Search Results (696)

Cardiac safety assessment is an integral part of drug discovery and development. Drug candidates that adversely affect cardiac or hemodynamic function should be discontinued early unless a favorable benefit-risk ratio for patients can be justified. In this hypothesis-generating work, we aimed to develop a conceptual framework for informing early safety risk assessment based on in vitro drug affinities to pharmacological targets. For illustration, we used the drug-induced cardiotoxicity rank (DICTrank) data comprising 1318 drugs with cardiac safety concerns according to FDA labeling. The data was enriched with information on affinity to the most plausible mechanistic targets, clinical drug exposure, and human plasma protein binding. We descriptively identified 18 target classes potentially associated with elevated cardiovascular risk: potassium channels (accounting alone for 20% of the ‘most concern’ safety group); adrenergic, dopamine, serotonin, androgen, sex hormone, and opioid receptors; cyclooxygenase; sodium and calcium channels; muscarinic and glucocorticoid receptors; phosphodiesterase; topoisomerase; angiotensin-converting enzyme; angiotensin II type 1 receptor; monoamine transporters, and acetylcholinesterase. Overall, 80% of the ‘most concern’ drugs compared with only 12% of the ‘no concern’ drugs were associated with these targets in this exploratory descriptive analysis. Concentration–response analyses revealed differences in target potency and free drug exposure that appeared associated with variability in the severity of cardiotoxicity among drugs acting on the same target. This framework demonstrates how in vitro data can be used to benchmark new compounds early in development, enabling the timely discontinuation of candidates associated with substantial risk. Full article

Background/Objectives: Promoting white adipose tissue (WAT) browning into thermogenic beige adipocytes is a promising anti-obesity strategy. Yanggyeoksanhwa-tang (YST) has been used traditionally to alleviate obesity-related conditions. Catalpol and rhoifolin are major bioactive components of Rehmannia glutinosa (Gaertn.) and Lonicera japonica (Thunb.) with known metabolic or anti-inflammatory effects. However, their direct roles in adipocyte browning and the mechanisms via β3-adrenergic receptor (β3-AR) signaling are not well defined, and this study addresses this gap. Methods: To evaluate browning potential, 3T3-L1 adipocytes were treated with catalpol and rhoifolin during differentiation. The expression of browning markers and lipid metabolism or catabolism transcription factors was analyzed using Western blotting and quantitative real-time polymerase chain reaction. The involvement of the β3-AR and adenosine monophosphate–activated protein kinase (AMPK) signaling pathways was further validated using specific agonists and antagonists. Results: Both compound treatments significantly upregulated beige-specific (Cd137, Cited, Tbx1, Cidea, Fgf21, Tmem26) and mitochondrial biogenesis markers (Cox4, Nrf1, Tfam), accompanied by a marked increase in thermogenic markers (UCP1, PGC-1α, Prdm16). Concurrently, lipolysis-related genes such as Atgl, Hsl, and Plin1 were elevated, while lipogenesis targets (Fasn, Lpl, Srebf1, Acaca) were downregulated through activation of the β3-AR signaling pathway. Conclusions: These findings suggest that catalpol and rhoifolin, key phytochemicals of YST, promote WAT browning and lipolysis. Our findings indicate that these compounds induce browning and modulate metabolism via the β3-AR pathway. These results serve as a cornerstone for natural anti-obesity therapy, pending further validation in vivo and clinical studies. Full article

Endometriosis is a chronic, estrogen-dependent inflammatory disease including aberrant local steroidogenesis, inflammation, angiogenesis, oxidative stress, and prostaglandin-mediated pain. Given the elevated adrenergic receptor expression in endometriotic lesions and the potential of terazosin to downregulate Steroidogenic Factor-1 (SF-1), this study aimed to evaluate terazosin as a non-hormonal therapy in a surgically induced rat endometriosis model. Forty female Wistar rats were randomized to sham, untreated endometriosis, leuprolide acetate or terazosin; two postoperative deaths yielded final group sizes of 10/9/10/9. Blinded histopathology verified successful lesion establishment. ELISA quantified SF-1, IL-6, IL-8, TNF-α, NF-κB, VEGF, HIF-1α, and PGE2 in lesion tissue, serum, and peritoneal lavage; oxidative status was assessed by TAS, TOS, and OSI. Compared with untreated endometriosis, terazosin significantly reduced SF-1, PGE2, IL-6, IL-8, TNF-α, VEGF and HIF-1α across compartments (all p < 0.001), comparable to leuprolide (p = 1.000). Terazosin also normalized oxidative stress by decreasing TOS/OSI and restoring TAS in tissue, serum, and peritoneal fluid (p < 0.001). NF-κB decreased in tissue and serum (p < 0.001) but not in peritoneal fluid (p = 0.206). Overall, terazosin produced leuprolide-like molecular benefits without hormonal suppression, supporting repurposing as a candidate non-hormonal therapy, while highlighting the need for longer-duration studies and randomized clinical trials given model and pain-assessment limitations. Full article

Hydrolyzed collagen (HC) derived from salmon skin is a promising source of bioactive peptides. In this study, the vasorelaxant effects and potential mechanisms of action of HC on isolated rat thoracic aorta rings were investigated using the organ bath technique. The vasorelaxant properties of HC were evaluated using aortic rings from Wistar rats pre-contracted with phenylephrine (PE) or potassium chloride (KCl). HC induced significant vasorelaxation in both endothelium-intact and endothelium-denuded rings, indicating that its mechanism of action was independent of the endothelium and involved direct effects on vascular smooth muscle cells. The vasorelaxant effect of HC was reduced when pre-contraction was induced by tetraethylammonium chloride (TEA). However, the vasodilatory effects of HC were not significantly inhibited by all K⁺ channel blockers, including glibenclamide, barium chloride (BaCl₂), or 4-aminopyridine (4-AP). Additionally, pre-incubation with prazosin, an α-adrenoceptor blocker, significantly reduced the vasorelaxation induced by HC, whereas propranolol, a β-adrenoceptor blocker, had no effect. In addition, HC inhibited CaCl₂-induced contractions induced by both PE and caffeine in a Ca²⁺-free solution. Therefore, HC exhibited the vasorelaxant effects through an endothelium-independent mechanism. The vasodilatory effects of HC were associated with the activation of K_Ca channels, suppression of PE-induced contraction via α₁-adrenergic receptor pathways, and inhibition of CaCl₂-induced contractions by modulating intracellular Ca²⁺ release and extracellular Ca²⁺ influx in vascular cells. Full article

Bronchial asthma is a common chronic respiratory disease with a complex etiology, wherein the interaction between genetic and environmental factors plays a critical role in its pathogenesis. The β-2 adrenergic receptor gene (ADRB2) is pivotal in regulating airway smooth muscle relaxation. Its genetic polymorphisms have been extensively studied and are closely associated with asthma susceptibility, clinical phenotypes, and drug responses. Recently, the relationship between major single-nucleotide polymorphisms (SNPs) of the ADRB2 gene and bronchodilator efficacy, alongside its transcriptional regulation and epigenetic modification mechanisms, has been progressively elucidated. Furthermore, ADRB2 genotype-guided therapeutic strategies have shown potential clinical and economic value in selected studies, but they remain exploratory and have not yet been incorporated into routine guideline-based asthma management algorithms. This review summarizes recent advances in the role of the ADRB2 gene concerning genetic susceptibility, disease phenotyping, environmental interactions, and immune regulation in asthma, aiming to provide theoretical support and clinical guidance for precision diagnosis and treatment. Full article

Venlafaxine, a serotonin–norepinephrine reuptake inhibitor, shows analgesic effects in rodents, but its efficacy and pharmacological profile in acute stimulus-evoked nociception may depend on the nociceptive test used and the pharmacological context. The aim of this review was to identify the receptors implicated in venlafaxine antinociceptive effects and to examine which molecular processes most consistently explain its acute antinociceptive profile. We reviewed in vivo rodent studies testing venlafaxine in acute nociceptive assays (writhing, tail-flick, hot-plate, and other eligible acute tests) as monotherapy or associated with other pharmacologically active substances. PubMed/MEDLINE and Web of Science were searched from 1993 to 5 January 2026, and reference lists were also screened. Outcomes were synthesized and stratified by type of nociceptive test and interaction class. Fourteen studies were identified as relevant to the scope of this review. Venlafaxine produced dose-dependent antinociception across tests, reducing writhing and increasing thermal withdrawal latency. Central administration generally yielded effects at lower absolute doses than systemic routes. Interaction studies most consistently supported modulation of opioid receptors (e.g., leftward opioid dose–response shifts and attenuation of morphine tolerance in repeated-exposure designs), with convergent evidence implicating opioid and α₂-adrenergic mechanisms and context-dependent serotonergic contributions. Additional pathways were variably implicated, including nitric oxide—cyclic guanosine monophosphate (NO–cGMP) signaling and oxidative/mitochondrial processes in opioid tolerance paradigms. Preclinical evidence supports venlafaxine as a modulator of acute nociceptive control with notable opioid-interaction potential. Standardized pharmacodynamic reporting and translationally oriented studies are needed. Full article

The escalating crisis of plastic pollution has positioned microplastics (MPs) as globally pervasive environmental contaminants, with a documented presence across aquatic, terrestrial, and atmospheric ecosystems, as well as within biological organisms. A growing body of evidence suggests that MPs not only threaten ecological integrity but may also induce multifaceted neurotoxic effects in humans, particularly targeting the functional architecture of the prefrontal cortex (PFC). As the central regulator of cognition, emotional processing, and behavioral control, PFC dysfunction has been hypothesized to be associated with cognitive deficits, emotional dysregulation, and behavioral abnormalities. In this comprehensive review, we synthesize the current understanding of MP-mediated neurotoxicity through three interconnected pathways: (1) structural and functional impairment of PFC neural networks, (2) disruption of neurotransmitter homeostasis, and (3) potential associations with neuropsychiatric pathogenesis. By integrating these mechanistic insights, this work aims to provide a scientific foundation for risk assessment frameworks and evidence-based environmental health policies. Full article

Objectives: Complex regional pain syndrome (CRPS) is a heterogeneous pain disorder with incompletely understood immunoinflammatory features. This study investigated whether autonomic receptor autoantibodies differentiate CRPS from other chronic pain conditions and healthy controls. Methods: We conducted a cross-sectional analysis of serum samples from patients referred with suspected CRPS. Patients were subsequently classified as having either CRPS or another chronic pain condition, based on the Budapest criteria. Healthy controls were included for comparison. Serum levels of autoantibodies targeting the muscarinic M2 receptor (M2R), β1-adrenergic receptor (β1AR), and the β2-adrenergic receptor (β2AR) were assessed using enzyme-linked immunosorbent assay. All analyses were performed blinded to group assignment. Results: Seventy participants were analyzed (CRPS = 22, other chronic pain = 25, healthy controls = 23). M2R autoantibody levels were higher in both CRPS and other chronic pain compared with healthy controls (mean difference [MD] = 0.37, 95%CI 0.22–0.51; and MD = 0.31 95%CI 0.19–0.44, respectively). β2AR levels were higher in other chronic pain compared with healthy controls (MD = 0.29, 95%CI 0.04–0.54), whereas no significant difference was observed in CRPS (MD = 0.21 95%CI −0.01–0.42). No meaningful differences were observed between CRPS and other chronic pain for any receptor. β1AR levels did not differ between groups. Seropositivity for any autoantibody was 55% in CRPS, 44% in other chronic pain, and 22% in healthy controls. Conclusions: Elevated autonomic receptor autoantibody levels were observed across chronic pain conditions but were not specific for CRPS. Full article

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide, with blast TBI (bTBI) particularly affecting military personnel and individuals exposed to explosive environments, yet there are no available curative treatments to date. While adrenergic receptor antagonists have shown promise in reducing neuroinflammation and improving TBI mortality rates, systemic administration of these drugs can have deleterious effects including bradycardia and hypotension. Here, we introduce a polymeric nanoparticle system for the delivery of adrenergic receptor antagonists, which allows for size-based targeting of the injured blood–brain barrier (BBB). These nanoparticles consist of chitosan-coated polylactic co-glycolic acid encapsulating the β-adrenergic receptor antagonist propranolol and/or the α-adrenergic receptor antagonist phenoxybenzamine. Particles designed with a 200 nm hydrodynamic diameter showed a 20–24% increase in permeability on an in vitro contact co-culture BBB model exposed to a 23 or 35 PSI acoustic blast when compared to uninjured controls, whereas 100 nm particles show no difference, suggesting blast injury induces BBB damage that enables the accumulation of larger particles. Treatment of blast-injured human brain microvascular cells with our nanoformulation reduced extracellular inflammatory cytokine levels and reduced the expression of pro-inflammatory markers in microglia. Moreover, these particles mitigated the upregulation of extracellular TNFα induced by free phenoxybenzamine in injured and uninjured microglia, suggesting nanoparticle drug encapsulation can reduce adverse drug reactions in the brain. Together, these findings provide proof-of-concept for size-based targeting and the potential anti-inflammatory effects of CS-PLGA nanoparticles containing adrenergic receptor antagonists for treatment of TBI and bTBI. Full article

Background/Objectives: Rho-associated protein kinase inhibitors reduce intraocular pressure (IOP) by enhancing aqueous humor outflow through the trabecular meshwork–Schlemm’s canal pathway. However, it remains unclear whether the fixed-dose combination of ripasudil hydrochloride hydrate and brimonidine tartrate (GLAALPHA) enhances conventional aqueous outflow in vivo. Methods: This single-center randomized clinical trial included healthy adult volunteers who received GLAALPHA, a brimonidine tartrate–brinzolamide fixed-dose combination (Ailamide), or brimonidine tartrate monotherapy (Aiphagan) in a crossover sequence. The aqueous column width in the episcleral veins was assessed at baseline and at 2 h (primary outcome) and 8 h using hemoglobin video imaging. Results: Among 24 participants, analyses included 23 GLAALPHA-treated eyes, 21 Ailamide-treated eyes, and 22 Aiphagan-treated eyes. Two hours after instillation, the aqueous column width significantly increased from baseline only in the GLAALPHA group (p = 0.002). The percent increase in the aqueous column width at 2 h was significantly greater with GLAALPHA than with Ailamide (p = 0.039) and not significantly different between GLAALPHA and Aiphagan (p = 0.114). At 8 h, the aqueous column width did not differ from the baseline in any groups. Conclusions: In healthy adult eyes, GLAALPHA significantly increased the aqueous column width in the episcleral veins 2 h after instillation, indicating enhanced conventional aqueous outflow. These findings provide evidence that GLAALPHA promotes trabecular outflow beyond the effects of brimonidine tartrate-containing comparators and offer mechanistic insights into its action. Full article

Neuroblastoma (NB) represents a paradigmatic developmental malignancy in which lineage specification, oncogenic signalling, and epigenetic regulation converge to define tumour behaviour. Among the molecular axes shaping NB heterogeneity, neurotrophin receptors of the tropomyosin receptor kinase (Trk) family (TrkA, TrkB, and TrkC) and the p75NTR occupy a central position at the intersection between neuronal differentiation programs and malignant plasticity. While high TrkA and TrkC expression is associated with adrenergic identity, differentiation competence, and favourable clinical outcome, TrkB, frequently sustained by BDNF-driven autocrine loops, characterises mesenchymal-like, therapy-resistant states enriched in metabolic and inflammatory adaptations. Importantly, in NB, the dysregulation of neurotrophin signalling rarely arises from recurrent genetic alterations of neurotrophic tyrosine receptor kinase (NTRK) loci. Instead, Trk receptor expression is dynamically shaped by promoter methylation, polycomb repressive complex 2/Enhancer of Zeste homolog 2 (PRC2/EZH2)-dependent chromatin repression, MYCN-driven transcriptional silencing, enhancer rewiring, and microRNA-mediated control. These epigenetic mechanisms govern reversible transitions along the adrenergic–mesenchymal (ADRN–MES) continuum, enabling tumour cells to adapt to microenvironmental and therapeutic stress. Single-cell and spatial multi-omics approaches have further revealed that Trk-associated phenotypes are embedded within complex regulatory circuits integrating receptor tyrosine kinase (RTK) networks, cytokine signalling, metabolic remodelling, and stromal reinforcement. Here, we provide a comprehensive synthesis of the epigenetic and microenvironmental mechanisms regulating neurotrophin receptors in NB, with particular emphasis on how chromatin plasticity and cell-state transitions reshape Trk-dependent signalling outputs. We discuss advanced three-dimensional and organoid-based models that recapitulate niche-specific regulation of the Trk axis and evaluate emerging therapeutic strategies combining epigenetic modulators, differentiation-inducing agents, and RTK-targeted compounds. Understanding the temporal and spatial dynamics of Trk signalling may open new opportunities to therapeutically stabilise differentiation states and disrupt adaptive resistance programs in high-risk NB. Full article

Objectives: Obesity remains a global health challenge, and promoting white adipose tissue browning has emerged as a promising anti-obesity strategy. This study aimed to investigate the anti-obesity effects of denatonium benzoate (DB) and elucidate its underlying mechanisms. Methods: In order to study the anti-obesity effects of DB and its mechanisms, we used in vivo and in vitro obesity models to study whether DB has anti-obesity effects by participating in fat browning. We investigated the role of DB in high-fat diet (HFD)-induced obese C57BL/6J mice using 36 male animals (8 weeks old, 25 ± 2 g), and evaluated the expression of the adipogenic marker genes Fatty acid-binding protein 4 (Fabp4) and Peroxisome Proliferator-Activated Receptor gamma (PPAR-γ); the thermogenic genes uncoupling protein 1 (Ucp1), Transcription Factor A, Mitochondrial (TFAM), Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-Alpha (Pgc1α), and Adrenergic receptor beta 3 (Adrb3); as well as the adipose browning marker genes Deiodinase, Iodothyronine, Type II (Dio2), PR domain containing 16 (PRDM16), and Peroxisome Proliferator-Activated Receptor alpha (PPAR-α) in 3T3-L1 cells and primary adipocytes with DB treatment. Conclusions: These results indicate that the anti-obesity effects of DB may be related to the browning of white fat, providing a novel potential candidate for anti-obesity drug development. Full article

Chronic stress is defined as a prolonged state of emotional disturbance and psychological strain resulting from an inability to maintain internal homeostasis. It is recognized as a significant risk factor for breast cancer, primarily through the chronic activation of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis. This neuroendocrine activation leads to elevated systemic levels of epinephrine, norepinephrine, and glucocorticoids. By binding to their respective adrenergic and glucocorticoid receptors, these hormones disrupt immune homeostasis and exacerbate oxidative stress within the tumor microenvironment. Such physiological shifts promote critical oncogenic processes, including angiogenesis and tumor cell proliferation, thereby driving the development, progression, and distant metastasis of breast cancer. Mastication, or the act of chewing, serves as a practical and effective behavioral strategy for modulating the deleterious effects of chronic psychological stress. Recent animal studies have provided compelling evidence that chewing can attenuate excessive stress responses. Specifically, it has been shown to mitigate stress-induced breast cancer progression and metastasis by modulating the expression of stress hormones, their corresponding receptors, and key downstream signaling pathways. These findings suggest that the rhythmic activity of chewing may exert a protective effect against stress-related tumor exacerbation. Consequently, further clinical research is warranted to determine whether chewing interventions can serve as a viable complementary strategy alongside conventional breast cancer prevention and treatment protocols. Full article

Bitter taste receptors (TAS2Rs) are G protein-coupled receptors best known for detecting bitter compounds in the oral cavity. However, their expression patterns and physiological roles in the liver remain largely unexplored. Here, we employed molecular and immunohistochemical approaches to demonstrate that multiple TAS2Rs are expressed in human Hep3B cells and mouse primary hepatocytes (MPHs) and co-localized with β-adrenergic receptors (βARs) at the bile canaliculi. Bioluminescence resonance energy transfer (BRET), cAMP assays, and Western blot analyses revealed that certain TAS2Rs exhibit ligand-dependent coupling preferences for the G protein subunits Gαi1, Gαi2, and Gαi3. This coupling leads to inhibition of cAMP production and a reduction in protein kinase A (PKA) substrate phosphorylation. Biochemical assays further showed that TAS2R activation significantly attenuates βAR-mediated lipolysis, as well as the production of glycerol and free fatty acid in both Hep3B cells and MPHs. These effects were partially reversed by small interfering RNA (siRNA)-mediated knockdown of TAS2Rs. Moreover, studies using a steatotic mouse model demonstrated that bitter compounds inhibit lipid droplet degradation, resulting in hepatic triacylglycerol accumulation. Collectively, these findings reveal a role for TAS2Rs in modulating hepatic lipid metabolism and highlight their potential as therapeutic targets for the prevention and treatment of liver diseases. Full article

Novel pharmacological approaches advocate developing multitarget drugs, that is, molecules capable of simultaneously acting on two or more pharmacological targets to produce synergistic effects from a single compound in each disease. This strategy may help reduce required doses and prevent drug–drug interactions typically associated with polypharmacy. Coumarins are natural products with diverse pharmacological activities, including antioxidant, anti-inflammatory, anticancer, neuroprotective, cardioprotective, and antithrombotic effects. The pleiotropic actions of these molecules suggest that modifying the coumarin structure could yield new multi-target antiplatelet agents with greater efficacy and safety than those currently available in clinical practice. In this work, we began with a theoretical approach using molecular docking and designed three coumarins that simultaneously inhibited platelet aggregation induced by epinephrine, collagen, and ADP. Experimentally, we evaluated the structure activity relationship of three coumarins: (A) 6,7-dimethoxy-3-(1H-pyrrol-1-yl)-2H-chromen-2-one, (B) 7,8-dimethoxy-3-(1H-pyrrol-1-yl)-2H-chromen-2-one, and (C) 3-(1H-imidazol-1-yl)-6,7-dimethoxy-2H-chromen-2-one. In silico studies suggest that compounds B and C may exhibit antagonistic interactions at the α₂-adrenergic, GPVI collagen, and P₂Y₁₂ ADP receptors. Additionally, molecular docking indicates essential interactions between the compounds and the GPIIb/IIIa fibrinogen receptor. Full article