Pulmonary arterial hypertension (PAH) is a complex condition involving genetic, molecular, and inflammatory factors. Recent studies have identified genetic abnormalities, particularly in the BMPR2 gene, as a key contributor to PAH. BMPR2 is part of the TGF-β superfamily and plays a critical role in vascular cell function. Mutations in BMPR2 are associated with hereditary PAH, and its loss leads to impaired signaling, contributing to vascular remodeling and hypertension. Other factors, such as inflammation, oxidative stress, and altered metabolism, also play significant roles in the pathogenesis of PAH. PAH is characterized by abnormal vascular remodeling, including muscularization of distal pulmonary arteries, thickening of vessel walls, and neointimal formation. These changes are driven by dysregulated endothelial and smooth muscle cell function, including increased proliferation and migration. Endothelial dysfunction, reduced nitric oxide production, and altered microRNA processing are key features of PAH. Inflammation and immune mechanisms are also central to PAH pathogenesis. Inflammatory mediators, such as S100A4 and fractalkine, contribute to vascular remodeling and SMC proliferation. Immune cells, including macrophages and T cells, are present in the vessel wall, further exacerbating the disease. Additionally, estrogen metabolism and gender differences influence PAH susceptibility. Emerging therapeutic strategies target various pathways, including BMPR2 signaling, inflammation, and metabolic dysregulation. Approaches such as gene therapy, PPARγ agonists, and inhibitors of PDGF and TGF-β signaling show promise in treating PAH. Additionally, targeting serotonin receptors and improving vascular regeneration through endothelial progenitor cells are being explored. The molecular pathogenesis of PAH involves a complex interplay between genetic predisposition, inflammation, and metabolic changes. Understanding these mechanisms is crucial for developing effective therapies. Current research highlights the importance of targeting multiple pathways to address the multifaceted nature of PAH.Pulmonary arterial hypertension (PAH) is a complex condition involving genetic, molecular, and inflammatory factors. Recent studies have identified genetic abnormalities, particularly in the BMPR2 gene, as a key contributor to PAH. BMPR2 is part of the TGF-β superfamily and plays a critical role in vascular cell function. Mutations in BMPR2 are associated with hereditary PAH, and its loss leads to impaired signaling, contributing to vascular remodeling and hypertension. Other factors, such as inflammation, oxidative stress, and altered metabolism, also play significant roles in the pathogenesis of PAH. PAH is characterized by abnormal vascular remodeling, including muscularization of distal pulmonary arteries, thickening of vessel walls, and neointimal formation. These changes are driven by dysregulated endothelial and smooth muscle cell function, including increased proliferation and migration. Endothelial dysfunction, reduced nitric oxide production, and altered microRNA processing are key features of PAH. Inflammation and immune mechanisms are also central to PAH pathogenesis. Inflammatory mediators, such as S100A4 and fractalkine, contribute to vascular remodeling and SMC proliferation. Immune cells, including macrophages and T cells, are present in the vessel wall, further exacerbating the disease. Additionally, estrogen metabolism and gender differences influence PAH susceptibility. Emerging therapeutic strategies target various pathways, including BMPR2 signaling, inflammation, and metabolic dysregulation. Approaches such as gene therapy, PPARγ agonists, and inhibitors of PDGF and TGF-β signaling show promise in treating PAH. Additionally, targeting serotonin receptors and improving vascular regeneration through endothelial progenitor cells are being explored. The molecular pathogenesis of PAH involves a complex interplay between genetic predisposition, inflammation, and metabolic changes. Understanding these mechanisms is crucial for developing effective therapies. Current research highlights the importance of targeting multiple pathways to address the multifaceted nature of PAH.