Search Results (235)

Hypoxic pulmonary hypertension (HPH) is a progressive vascular disease characterized by an abnormal increase in pulmonary arterial pressure resulting from pulmonary vasoconstriction and pulmonary vascular remodeling (PVR). Excessive proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) are key drivers of PVR. Caragana jubata (Pall.) Poir. (C. jubata), known as “zuomaoxing” in Tibetan medicine, is traditionally used to treat blood-related disorders. However, the potential preventive and therapeutic effects of C. jubata on HPH remain unclear. Here, we integrated in vivo pharmacology, serum pharmacochemistry, PASMC assays, DARTS-MS chemoproteomics, and pathway validation to investigate the effects of C. jubata ethanol extract (ECJ) on HPH-associated PVR and the effects of a serum-exposed candidate component on CoCl₂-induced PASMC activation. In HPH rats, ECJ reduced mean pulmonary arterial pressure and alleviated right ventricular hypertrophy and PVR. Serum pharmacochemistry detected 47 ECJ-derived serum-exposed features, including one prototype putatively annotated as ginkgolide J. Ginkgolide J attenuated CoCl₂-induced PASMC proliferation, Ki-67 positivity, and migration without significantly affecting PASMC viability. DARTS-MS identified 1235 ginkgolide J-associated protease-susceptibility candidate proteins, and pathway validation indicated that ginkgolide J suppressed CoCl₂-induced MEK1/ERK1/2 activation. These findings suggest that ECJ has potential value against HPH-associated PVR and that ginkgolide J is a candidate anti-proliferative compound in PASMCs. Full article

Background: Solriamfetol, a dopamine and norepinephrine reuptake inhibitor widely used in narcolepsy management, has not been thoroughly investigated for its anti-fibrotic and anti-inflammatory properties. Herein, we investigated its potential therapeutic applications and underlying mechanisms in both cellular and murine models of pulmonary fibrosis. Methods: To induce fibrosis, C57BL/6 male mice (six-week-old) were administered bleomycin via the intratracheal route. These animals subsequently received solriamfetol orally once per day at dosages of 3 or 10 mg/kg. Histological and immunohistochemical techniques were employed to evaluate inflammatory cell infiltration, collagen accumulation, and α-smooth muscle actin (α-SMA) expression in bronchoalveolar lavage samples and lung tissue sections. Cytokine levels were measured by ELISA, and gene/protein expression of pro-fibrotic markers, A_2A/A_2B adenosine receptors (ARs), adenylate cyclases (ACs), Epac, K_Ca3.1, and adenosine deaminase (ADA) were assessed via quantitative PCR and Western blot. Electrophysiological recordings evaluated K_Ca3.1 channel activity. Purified ADA and normal human lung fibroblasts (NHLFs) were treated with solriamfetol to assess effects on ADA activity and levels of cAMP and adenosine, respectively. Results: Solriamfetol significantly reduced inflammatory cell infiltration, collagen accumulation, and α-SMA expression in fibrotic lungs. Solriamfetol restored downregulated A_2AAR, A_2BAR, ACs, and Epac, while suppressing ADA expression and activity, resulting in elevated extracellular adenosine and intracellular cAMP. The intervention potentiated Epac signaling and inhibited fibroblast activation. Solriamfetol inhibited the K_Ca3.1 current in fibroblasts and reduced K_Ca3.1 protein expression levels in TGFβ-treated fibroblasts and lung tissues from bleomycin-challenged mice. Notably, these effects were abolished by A_2AAR or A_2BAR antagonists, implying that they occur through AR-mediated pathways. Conclusions: Solriamfetol inhibits ADA and reinforces adenosine–cAMP signaling, suppressing pathological fibroblast activation. These findings suggest its therapeutic utility as a novel anti-fibrotic compound for various fibrotic diseases, including pulmonary fibrosis. Full article

Iron is essential for life, but its safe use by the body depends on it being kept within tightly controlled compartments. When this compartmentalisation is disrupted—through haemolysis, saturation of scavenger proteins, or dysregulation of the hepcidin–ferroportin axis—damaging iron species accumulate in the circulation and within vascular cells, with potentially serious consequences for endothelial function. This review explores the mechanisms by which iron dysregulation compromises vascular endothelial cell biology across a range of disease states, including haemolytic anaemias, atherosclerosis, cerebrovascular disease, extracorporeal circulatory support, and iatrogenic iron loading. Common pathological themes emerge: depletion of nitric oxide bioavailability, oxidative stress, endothelial activation, and in chronic settings, vascular remodelling. The review subsequently focuses in depth on the pulmonary vasculature, where dysregulated iron compartmentalisation has emerged as a key contributor to the pathogenesis of pulmonary hypertension. Here, iron-driven mitochondrial dysfunction, smooth muscle cell proliferation, and iron-dependent lipid peroxidation via ferroptosis are discussed as mechanistic drivers of pulmonary vascular remodelling. The therapeutic implications of targeting iron handling in pulmonary hypertension are considered, including modulation of the hepcidin–ferroportin axis. Together, the evidence presented highlights disordered iron compartmentalisation as a unifying pathological thread across vascular disease and a compelling target for intervention. Full article

Cardiovascular remodeling, encompassing vascular remodeling, myocardial remodeling, and fibrosis-associated tissue remodeling, underlies atherosclerosis, pulmonary hypertension, myocardial infarction, myocardial fibrosis, and other cardiovascular diseases. Its regulation has traditionally been studied through transcriptional, inflammatory, metabolic, mechanical, and intercellular signaling mechanisms. Recent advances in epitranscriptomics have identified N6-methyladenosine (m⁶A) RNA methylation as an additional post-transcriptional layer that interacts with microRNA (miRNA) pathways during cardiovascular disease progression. This review summarizes current evidence for m⁶A-miRNA crosstalk in cardiovascular remodeling, focusing on epitranscriptomic checkpoints that regulate miRNA fate, feedback-like regulatory circuits involving miRNAs and the m⁶A machinery, and cell-type-specific programs across endothelial cells, vascular smooth muscle cells, fibroblasts, and cardiomyocytes. We further discuss emerging analytical technologies and translational implications of this regulatory axis. Future studies should clarify causal mechanisms, cell-type and disease-stage specificity, and translational feasibility. Together, this multilayered framework provides a systems-level perspective on how RNA regulatory networks may shape pathological remodeling in cardiovascular disease. Full article

Pulmonary arterial hypertension (PAH) is a progressive, fatal disease of the pulmonary vasculature characterized by obliterative remodeling of small pulmonary arteries, leading to sustained elevation of pulmonary vascular resistance, right ventricular failure, and premature death. The diagnostic gold standard remains right heart catheterization, requiring a mean pulmonary artery pressure greater than 20 mmHg at rest, a pulmonary arterial wedge pressure of 15 mmHg or below, and a pulmonary vascular resistance exceeding 2 Wood units. PAH is an autosomal dominant disorder with markedly incomplete penetrance of approximately 20–30%, indicating that germline mutations alone are insufficient to cause disease. Disease manifestation requires additional “second hits”, including chronic hypoxia, systemic inflammation, hemodynamic stress, hormonal influences, and common genetic modifiers such as single-nucleotide polymorphisms (SNPs). This genetic and environmental complexity underpins the broad clinical heterogeneity observed across PAH subtypes, which include idiopathic PAH, heritable PAH, and disease associated with connective tissue disorders, HIV infection, portal hypertension, congenital heart disease, schistosomiasis, and drug or toxin exposure. This review provides a comprehensive and critical appraisal of the molecular-genetic architecture of PAH. Thirty genes have now been implicated in disease pathogenesis, spanning seven functional categories: receptors of the TGF-β/BMP signaling family (BMPR2, ACVRL1, ENG, BMPR1B); circulating BMP ligands (GDF2, BMP10); transcription factors (TBX4, SOX17, KLF4, FOXF1, SMAD1, SMAD4, SMAD9); membrane and polyamine transporters (ATP13A3, AQP1); potassium channel regulators (KCNA5, KCNK3, ABCC8); metabolic and mitochondrial genes (EIF2AK4, NFU1, GGCX); signaling receptors and structural proteins (NOTCH3, KDR, CAV1, PLEKHH2); vasoactive and extracellular matrix regulators (KLK1, CBLN2, CD248); and epigenetic regulators (TET2, TOPBP1). Among these, BMPR2 is the dominant contributor, accounting for 53–86% of heritable PAH and 14–35% of idiopathic cases. The remaining genes each account for fewer than 5% of cases individually, collectively reflecting a broad landscape of rare and ultra-rare genetic contributions. For each gene, we critically evaluate the strength of genetic evidence, pathogenic mechanisms, degree of mechanistic resolution, and clinical relevance. We further discuss the contribution of emerging technologies, including whole-genome sequencing, single-cell and spatial transcriptomics, multi-omics integration, iPSC-derived vascular models, and artificial intelligence, to expanding the PAH genetic architecture beyond single-gene discovery. A key theme across this landscape is convergence: despite mechanistic diversity at the gene level, most PAH-associated variants ultimately impair endothelial quiescence, promote smooth muscle proliferation, and drive apoptosis resistance through disruption of BMP signaling amplitude, transcriptional stability, ion channel homeostasis, metabolic integrity, or epigenetic regulation. This convergence supports both a unified therapeutic rationale and a precision medicine framework for genotype-stratified intervention in PAH. Full article

The yak (Bos grunniens), a unique bovine species that is endemic to the Qinghai–Tibet Plateau and adjacent mountainous regions, exhibits remarkable adaptations to chronic high-altitude hypoxia. However, the molecular mechanisms underlying yaks’ adaptation to this extreme environment remain poorly understood. This study aimed to elucidate the spatiotemporal expression dynamics of hypoxia-inducible factor 1α (HIF-1α) and 2α (HIF-2α) in major tissues of yaks across developmental stages (0.5, 1.5, 2.5, and 4.5 years; n = 3 per group). The tissues (heart, liver, spleen, lungs, kidneys, blood vessels and skeletal muscles) were analyzed using hematoxylin and eosin (H&E) staining and immunohistochemistry. The results revealed significant differences in the expression levels of HIF-1α and HIF-2α between tissues and at different ages. In cardiac tissue, both HIF-1α and HIF-2α are localized to the myocardial interstitium, with HIF-1α expression peaking at 1.5–2.5 years and HIF-2α expression reaching its maximum at 2.5 years. Hepatic HIF-1α showed perivenous hepatocytes enrichment and peaked at 2.5 years (p < 0.01 vs. other ages), while HIF-2α was uniformly distributed across lobules without age-related changes. Splenic HIF-1α and HIF-2α levels increased progressively with age, both peaking at 4.5 years (p < 0.01), and age was strongly correlated with expression levels (HIF-1α: r = 0.430; HIF-2α: r = 0.493). In pulmonary tissues, HIF-1α in bronchial smooth muscle peaked at 2.5 years, whereas alveolar septal HIF-2α peaked at 1.5 years (p < 0.05). In the kidney, HIF-1α was primarily localized to tubular epithelial cells and HIF-2α was diffusely distributed in the glomerular interstitium; neither factor showed significant variation across ages. In vascular tissues, HIF-1α expression remained stable across all ages and was predominantly observed in the smooth muscle layer, while HIF-2α exhibited a significant peak in endothelial cells at 2.5 years (p < 0.01). These findings suggest that HIF-1α predominates during early development stages, while HIF-2α becomes dominant as yaks approach maturity. Full article

Pulmonary arterial hypertension (PAH) is a severe and progressive cardiopulmonary disorder with limited treatment options. Camellia petelotii (Merr.) Sealy (CP) contains multiple flavonoids and other phytochemicals, but its active compounds and molecular mechanisms in PAH remain unclear. Active compounds of CP were screened by comprehensive literature mining and absorption, distribution, metabolism, and excretion (ADME) evaluation. PAH-related hub targets were identified from transcriptomic data using weighted gene co-expression network analysis (WGCNA), machine learning, and external validation. Functional enrichment, immune infiltration, and single-cell RNA-sequencing analyses were performed to characterize their biological roles and cellular localization. Molecular docking and molecular dynamics simulations assessed compound–target interactions. The effects of CP were further evaluated in hypoxia-induced rat pulmonary artery smooth muscle cells (RPASMCs). Five core bioactive compounds were identified, among which luteolin and quercetin were prioritized for further analysis. HSP90AA1 and ROCK2 were screened as hub targets. Bioinformatic analyses suggested that these targets were mainly associated with the “Lipid and atherosclerosis” pathway, metabolic reprogramming, and modulation of the immune microenvironment. Single-cell analysis showed broad expression of HSP90AA1 and enrichment of ROCK2 in fibroblasts and endothelial cells. Molecular docking and molecular dynamics simulations supported stable binding of luteolin to HSP90AA1. In vitro, CP extract inhibited hypoxia-induced hyperproliferation of RPASMCs and reduced HSP90AA1 protein expression. HSP90AA1 may represent a candidate molecular mediator of CP in PAH, and CP inhibited hypoxia-induced RPASMC proliferation in association with downregulation of HSP90AA1. Full article

Objectives: Downregulation of the endogenous gasotransmitter hydrogen sulfide (H₂S) contributes to the pathogenesis of pulmonary arterial hypertension (PAH). While prophylactic H₂S supplementation prevents PAH initiation in different rat models, its ability to reverse fully established PAH and pulmonary vascular structural remodeling is unknown. In this study, we aimed to test whether H₂S donor therapy can reverse the existing PAH in a chronic-hypoxia rat model. Methods: After 3 weeks of hypoxia exposure, rats with established hypoxia-induced pulmonary hypertension (HPH) were randomized to receive either continued hypoxia alone or hypoxia plus the H₂S donor NaHS (56 μmol/kg·d, ip) for an additional 6 weeks. Pulmonary artery pressure, pulmonary artery muscularization, and right ventricular hypertrophy were assessed. Furthermore, the cell proliferation (Ki-67 and PCNA), ERK1/2 phosphorylation, and persulfidation of the endothelin type A receptor (ETAR) were examined and detected in rat lung tissues and pulmonary artery smooth muscle cells (PASMCs). Results: H₂S therapy effectively reversed established HPH and pulmonary artery structural remodeling, reducing RVSP, mPAP, and the proportion of fully muscularized small pulmonary arteries by 13.8%, 12.0%, and 62.7%, respectively. Moreover, the PAT/PET ratio was normalized to normoxic levels. The right ventricular hypertrophy index decreased by 29.2%. Mechanistically, H₂S therapy suppressed PASMC proliferation, reduced ERK1/2 phosphorylation, and enhanced ETAR persulfidation. Furthermore, dithiothreitol-mediated reduction of ETAR persulfidation abrogated these antiproliferative effects of H₂S therapy, establishing persulfidation as an obligatory mechanism. Conclusions: H₂S donor therapy effectively reverses established HPH and pulmonary vascular structural remodeling by inhibiting PASMC proliferation, which is linked to enhanced ETAR persulfidation. These data provide preclinical proof-of-concept for H₂S-based interventions in patients with manifest PAH. Full article

The vitamin D receptor (VDR) acts as both a nuclear transcription factor and a non-genomic mediator that regulates a broad spectrum of physiological processes beyond calcium and phosphate homeostasis. VDR plays an important role in the modulation of ion channels across multiple tissues, including osteoblasts, renal and intestinal epithelial cells, neurons, and vascular smooth muscle. These regulatory mechanisms encompass genomic actions through vitamin D response elements in target genes—such as TRPV5, TRPV6, KCNK3, and KCNH1—as well as rapid, non-genomic actions at the plasma membrane involving protein disulfide isomerase A3 and associated signaling cascades. VDR-mediated transcriptional control of calcium, potassium, and chloride channels contributes to the fine-tuning of cellular excitability, calcium transport, and mitochondrial function. Evidence also implicates VDR–ion channel crosstalk in various pathological contexts, including renal cell carcinoma, breast and cervical cancers, pulmonary arterial hypertension, and osteoporosis. Understanding the molecular interplay between VDR and ion channels provides new perspectives on the pleiotropic effects of vitamin D and offers promising therapeutic opportunities in oncology, cardiovascular disease, and skeletal disorders. This review synthesizes previous and current evidence on the genomic and non-genomic mechanisms underlying VDR–ion channel regulation and highlights novel frontiers in vitamin D signaling relevant to human health and disease. Full article

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease characterized by irreversible fibrosis. Aberrant cell differentiation plays a crucial role in the development of IPF. Although recent studies have suggested that mitochondrial dysfunction may play a role in IPF, its direct impact on fibrosis remains unclear. This study aimed to clarify the role of mitochondria in lung cell differentiation and pulmonary fibrosis development by employing mito-mice ND6^M, in which the activity of respiratory chain complex I is decreased due to a mitochondrial DNA mutation (G13997A). Pulmonary fibrosis was induced by administering bleomycin (BLM) to both wild-type and mito-mice ND6^M. Bone marrow-derived macrophages and primary lung fibroblasts, generated from both types of mice, were analyzed to evaluate M1/M2 polarization and myofibroblast differentiation, respectively. Compared to wild-type mice, mito-mice ND6^M exhibited more severe fibrosis and lower survival rates following BLM inoculation. Lactate production in the lungs after BLM administration was significantly higher in mito-mice ND6^M than in wild-type mice. TGF-β1-treated fibroblasts from mito-mice ND6^M exhibited increased α-smooth muscle actin expression. While type I collagen expression was not different between these mice, TGF-β1-induced expression of phosphoserine phosphatase and serine hydroxymethyltransferase2, two of the enzymes involved in the serine–glycine pathway, was significantly higher in mito-mice ND6^M than in wild-type mice. On the other hand, mitochondrial dysfunction had a small effect on pulmonary inflammation and on M1/M2 macrophage polarization. In conclusion, mitochondrial dysfunction promotes TGF-β1-induced myofibroblast differentiation and BLM-induced pulmonary fibrosis. Mitochondria-dependent metabolic reprogramming may therefore represent a promising therapeutic target in IPF. Full article

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by the pathological accumulation of collagen-rich extracellular matrix, resulting in irreversible lung remodeling and respiratory failure. The incomplete understanding of IPF pathogenesis has hindered the development of effective therapeutics. Here, we investigate the mechanism by which the actin-related protein 2/3 complex subunit 2 (ARPC2) contributes to the fibrotic response in lung fibroblasts. Modulating of ARPC2 expression levels altered the expression of profibrotic genes, including α-smooth muscle actin (ACTA2), in TGF-β1-treated MRC-5 cells at the transcriptional level. We further show that ARPC2 regulates the TGF-β1-mediated nuclear translocation of myocardin-related transcription factor-A (MRTFA), a central driver of fibrotic gene induction. Our data indicate that ARPC2 plays a distinct role in profibrotic gene expression and MRTFA nuclear localization, distinguishing its function from other components of the actin-related protein 2/3 (ARP2/3) complex. Furthermore, ARPC2 appears to modulate the TGF-β1-dependent formation of MRTFA/G-actin complexes. Finally, transcriptomic analysis of cells depleted of ARPC2, ACTR2, or MRTFA revealed that ARPC2 and MRTFA co-regulate a specific repertoire of fibrotic genes. These observations support a profibrotic function for ARPC2 during fibroblast-to-myofibroblast transition (FMT), highlighting it as a potential therapeutic target for IPF. Full article

Pulmonary arterial hypertension (PAH) is characterized by dysfunction and remodeling of the pulmonary artery endothelium and smooth muscle. In heritable PAH, heterozygous loss-of-function mutations in the type II Bone Morphogenetic Protein (BMP) receptor gene (BMPR2) are the most common genetic cause. However, the mechanisms by which reduced BMPR2 levels alter endothelial signaling to drive PAH pathogenesis remain incompletely understood. To determine how BMPR2 levels govern signaling output and endothelial functional responses, we modulated BMPR2 expression in human pulmonary artery endothelial cells (PAECs) and assessed ligand-dependent SMAD1/5/8 signaling, proliferation, and caspase-3/7 activity. We found that BMP9 and BMP10 robustly activated SMAD1/5/8 signaling and promoted proliferation in PAECs, whereas the other ligands in this panel did not elicit a comparable signaling or proliferative response under these assay conditions. A moderate (~50%) reduction in BMPR2 protein levels (an in vitro approximation of haploinsufficiency) attenuated BMP9/10-induced SMAD1/5/8 activation, abolished proliferative responses, and was associated with a modest increase in caspase-3/7 activity, consistent with caspase pathway activation and early stress/injury signaling. Under BMPR2-limiting conditions, BMP9/10 responses became sensitive to Activin type II receptor blockade by bimagrumab, consistent with a context-dependent contribution of Activin type II receptors. Conversely, BMPR2 overexpression enhanced BMP9/10-dependent SMAD signaling and proliferation. Together, these findings support a receptor–dosage model where physiological BMPR2 expression is required to sustain homeostatic BMP9/10 signaling in pulmonary artery endothelium. This framework provides a basis for interpreting context-dependent pathway effects in PAH. Full article

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by endothelial dysfunction, vascular remodeling, and a sustained increase in pulmonary vascular resistance, causing cardiopulmonary damage. The apelin receptor (APJ), a member of the G protein-coupled receptor family, has emerged as an essential modulator of vascular homeostasis. Clinical and preclinical studies have demonstrated that its activation exerts beneficial effects on the progression of PAH. Its main actions include the restoration of endothelial function, reactivation of the BMPR2/SMAD axis, induction of nitric oxide-mediated vasodilation, inhibition of autophagy and the migration of the pulmonary artery smooth muscle cells (PASMCs). Furthermore, its expression and functionality are modulated by epitranscriptomic mechanisms, particularly by microRNAs involved in the post-transcriptional regulation of key genes for vascular homeostasis. These findings position the APJ as a relevant therapeutic target in PAH. However, the clinical application of its agonists still faces pharmacokinetic limitations that restrict their therapeutic use. Therefore, the aim of this review is to gather current information on APJ in the pathophysiology of PAH and focus attention on its potential as a therapeutic target. Full article

Hypoxic pulmonary vasoconstriction (HPV) is a rapid and reversible constrictor response of the pulmonary vasculature, and especially its small muscular precapillary arteries, which is initiated by episodes of local alveolar hypoxia. Acting as a protective homeostatic vasomotor mechanism, HPV enables maximal gas exchange by diverting blood from poorly ventilated alveoli into those rich in oxygen, thereby optimizing oxygen uptake and the ventilation–perfusion (V/Q) ratio so as to maintain the arterial oxygen partial pressure (P_aO₂) within the physiological range. HPV is an intrinsic mechanism of pulmonary artery smooth muscle cells (PASMCs), and requires an O₂ sensor which acts through mediator(s) to trigger effector mechanisms within these cells to evoke constriction. Whereas HPV effector mechanisms are reasonably well defined, the nature of the O₂ sensor and mediators remains in dispute, and a number of proposals have been developed to account for these. Some (but not all) of these share a focus on the concept that hypoxia activates effector mechanisms by inducing a change in the PASMC cytoplasmic redox state. Of these, the Redox Theory, first proposed by Kenneth Weir and Stephen Archer in 1995, proposes that hypoxia inhibits mitochondrial production of reactive oxygen species (ROS), thereby causing the cytoplasm to become more reduced. This inhibits ongoing vasorelaxation maintained by the opening of voltage-gated K⁺ channels. In contrast, according to the Mitochondrial ROS hypothesis, introduced by Paul Schumacker and Naveen Chandel in 2001, hypoxia increases mitochondrial ROS production, causing an oxidizing shift in the cytoplasmic redox state that activates several vasoconstricting pathways. In a third redox-based scenario, developed by Michael Wolin and Sachin Gupte, hypoxia evokes contraction by causing a fall in H₂O₂ production by NADPH oxidase and by activating the pentose phosphate pathway. These effects inhibit basal vasorelaxation maintained by the guanylate cyclase and protein kinase G and also stimulate vasoconstricting mechanisms. In this comprehensive review, we first provide a detailed summary of the key studies contributing to the development of these proposals and then subject the evidence supporting them to a critical appraisal, based in part on how well they accord with the wider literature and recent developments in our understanding of how cells shape and deploy redox mechanisms in order to regulate cell function. Full article

Pulmonary hypertension (PH) is a progressive disorder characterized by elevated pulmonary arterial pressure and the extensive remodeling of pulmonary vasculature. Chronic intermittent hypoxia (CIH), a hallmark of obstructive sleep apnea (OSA), is a well-established contributor to the pathogenesis of PH. OSA is defined by repetitive episodes of upper airway obstruction during sleep, leading to cycles of hypoxia and reoxygenation that trigger a cascade of deleterious events including oxidative stress, inflammation, endothelial dysfunction, and vascular remodeling. Growing evidence underscores the critical role of transient receptor potential canonical (TRPC) channels in mediating hypoxia-induced vascular alterations that contribute to the development of PH. TRPC channels are non-selective cation channels that regulate calcium influx in response to mechanical stimuli, pro-inflammatory cytokines, oxidative stress, and hypoxia. These channels are expressed in both pulmonary arterial smooth muscle cells (PASMCs) and pulmonary artery endothelial cells (PAECs), where they modulate key processes such as proliferation, migration, apoptosis, endothelial permeability, and vasoconstriction. Under hypoxic conditions, the upregulation of TRPC1, TRPC3, TRPC4, and TRPC6 has been implicated in dysregulation of calcium homeostasis and activation of pathological signaling pathways that contribute to increased pulmonary arterial pressure. In this review, we propose that upregulation and functional modulation of TRPC channels under CIH represents a central pathogenic mechanism linking OSA to PH. We hypothesize that TRPC1, TRPC3, TRPC4, and TRPC6 act as critical molecular effectors mediating hypoxia-driven calcium influx and downstream signaling pathways that lead to pulmonary vascular remodeling, endothelial dysfunction, and increased pulmonary arterial pressure. This framework allows us to integrate mechanistic insights from molecular, cellular, and translational studies, and to evaluate the therapeutic potential of targeting TRPC channels in OSA-associated PH. Full article