Department of General Practice, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China.
Guangxi Key Laboratory of Diabetic Systems Medicine, Guilin Medical University, Guilin, Guangxi, China.
Cell Commun Signal. 2024 Oct 11;22(1):492. doi: 10.1186/s12964-024-01859-5.
Endothelial cell (EC) senescence and vascular aging are important hallmarks of chronic metabolic diseases. An improved understanding of the precise regulation of EC senescence may provide novel therapeutic strategies for EC and vascular aging-related diseases. This study examined the potential functions of Spinster homolog 2 (SPNS2) in EC senescence and vascular aging. We discovered that the expression of SPNS2 was significantly lower in older adults, aged mice, hydrogen peroxide-induced EC senescence models and EC replicative senescence model, and was correlated with the expression of aging-related factors. in vivo experiments showed that the EC-specific knockout of SPNS2 markedly aggravated vascular aging by substantially, impairing vascular structure and function, as evidenced by the abnormal expression of aging factors, increased inflammation, reduced blood flow, pathological vessel dilation, and elevated collagen levels in a naturally aging mouse model. Moreover, RNA sequencing and molecular biology analyses revealed that the loss of SPNS2 in ECs increased cellular senescence biomarkers, aggravated the senescence-associated secretory phenotype (SASP), and inhibited cell proliferation. Mechanistically, silencing SPNS2 disrupts pyruvate metabolism homeostasis via pyruvate kinase M (PKM), resulting in mitochondrial dysfunction and EC senescence. Overall, SPNS2 expression and its functions in the mitochondria are crucial regulators of EC senescence and vascular aging.
内皮细胞(EC)衰老和血管老化是慢性代谢性疾病的重要标志。深入了解 EC 衰老的确切调控机制可能为 EC 和血管老化相关疾病提供新的治疗策略。本研究探讨了 Spnster 同源物 2(SPNS2)在内皮细胞衰老和血管老化中的潜在作用。我们发现 SPNS2 的表达在老年人、老年小鼠、过氧化氢诱导的 EC 衰老模型和 EC 复制性衰老模型中显著降低,且与衰老相关因子的表达相关。体内实验表明,内皮细胞特异性敲除 SPNS2 可通过显著加重血管老化,损害血管结构和功能,从而导致衰老因子异常表达、炎症增加、血流减少、病理性血管扩张和胶原水平升高,这在自然衰老小鼠模型中得到了证实。此外,RNA 测序和分子生物学分析表明,EC 中 SPNS2 的缺失增加了细胞衰老生物标志物,加重了衰老相关分泌表型(SASP),并抑制了细胞增殖。机制上,沉默 SPNS2 通过丙酮酸激酶 M(PKM)破坏了丙酮酸代谢平衡,导致线粒体功能障碍和 EC 衰老。总之,SPNS2 的表达及其在线粒体中的功能是 EC 衰老和血管老化的重要调节因子。