Channels (Austin). 2026 Dec;20(1):2709185. doi: 10.1080/19336950.2026.2709185. Epub 2026 Jul 26.
ABSTRACT
Store-operated calcium entry (SOCE) mediated by STIM and Orai proteins is a fundamental Ca2+ influx mechanism that critically regulates intracellular calcium homeostasis and participates in cardiovascular pathophysiology. Upon endoplasmic reticulum Ca2+ store depletion, STIM1/2 activate plasma membrane Orai1/3 channels, initiating Ca2+ entry that drives vasoconstriction, smooth muscle proliferation, platelet activation, and cardiac hypertrophy. Dysregulated SOCE is closely associated with hypertension, atherosclerosis, pulmonary hypertension, and thromboembolic disorders. However, SOCE is not a simple binary pathway but operates within a complex regulatory network. Beyond the core STIM-Orai axis, auxiliary proteins including transient receptor potential canonical 1 (TRPC1), tetraspanin 18 (Tspan18), tropomyosin 3 (TPM3), SOCE-associated regulatory factor (SARAF), and A-kinase anchoring protein 79/150 (AKAP79/150) modulate SOCE amplitude, kinetics, and downstream signaling in a cell- and context-dependent manner. Moreover, the functional consequences of SOCE are highly heterogeneous: Orai1 protects adult cardiomyocytes but promotes pathological hypertrophy in neonatal cells, posing a therapeutic dilemma. Although preclinical studies have shown efficacy of SOCE inhibitors, clinical translation remains hindered by poor isoform selectivity, suboptimal pharmacokinetics, lack of tissue-specific delivery, disease-stage-dependent effects, and absence of validated biomarkers. Importantly, recent evidence has definitively ruled out amlodipine-induced CRAC channel activation at therapeutic concentrations, confirming it as an experimental artifact. This review systematically summarizes the molecular complexity, functional diversity, and translational barriers of STIM/Orai-mediated SOCE, aiming to inform precision therapeutic strategies for cardiovascular diseases.
PMID:42503223 | DOI:10.1080/19336950.2026.2709185