Zhuang Yuting, Li Tingting, Xiao Hongwen, Wu Jiaxu, Su Shuang, Dong Xue, Hu Xiaoxi, Hua Qi, Liu Junwu, Shang Wendi, Ju Jiaming, Sun Fei, Pan Zhenwei, Lu Yanjie, Zhang Mingyu
Department of Pharmacology (State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Medicine Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China.
China Northern Translational Medicine Research and Cooperation Center, Heilongjiang Academy of Medical Sciences, Harbin Medical University, Harbin, China.
Front Pharmacol. 2021 Feb 16;12:631835. doi: 10.3389/fphar.2021.631835. eCollection 2021.
Cardiomyocyte senescence is associated with a progressive decline in cardiac physiological function and the risk of cardiovascular events. lncRNA H19 (H19), a well-known long noncoding RNA (lncRNA), is involved in the pathophysiological process of multiple cardiovascular disease such as heart failure, cardiac ischemia and fibrosis. However, the role of H19 in cardiomyocyte senescence remains to be further explored. Senescence-associated β-galactosidases (SA-β-gal) staining was used to detect cardiomyocyte senescence. Western blot, qRT-PCR and luciferase reporter assay were employed to evaluate the role of H19 in cardiomyocyte senescence and its underling molecular mechanism. H19 level was significantly increased in high glucose-induced senescence cardiomyocytes and aged mouse hearts. Overexpression of H19 enhanced the number of SA-β-gal-positive cells, and the expression of senescence-related proteins p53 and p21, whereas H19 knockdown exerted the opposite effects. Mechanistically, H19 was demonstrated as a competing endogenous RNA (ceRNA) for microRNA-19a (miR-19a): H19 overexpression downregulated miR-19a level, while H19 knockdown upregulated miR-19a. The expression of SOSC1 was dramatically increased in senescence cardiomyocytes and aged mouse hearts. Further experiments identified SOCS1 as a downstream target of miR-19a. H19 upregulated SOCS1 expression and activated the p53/p21 pathway by targeting miR-19a, thus promoting the cardiomyocytes senescence. Our results show that H19 is a pro-senescence lncRNA in cardiomyocytes acting as a ceRNA to target the miR-19a/SOCS1/p53/p21 pathway. Our research reveals a molecular mechanism of cardiomyocyte senescence regulation and provides a novel target of the therapy for senescence-associated cardiac diseases.
心肌细胞衰老与心脏生理功能的逐渐衰退以及心血管事件风险相关。长链非编码RNA H19（H19）是一种著名的长链非编码RNA，参与多种心血管疾病如心力衰竭、心肌缺血和纤维化的病理生理过程。然而，H19在心肌细胞衰老中的作用仍有待进一步探索。采用衰老相关β-半乳糖苷酶（SA-β-gal）染色检测心肌细胞衰老。运用蛋白质免疫印迹法、实时定量聚合酶链反应和荧光素酶报告基因检测法评估H19在心肌细胞衰老中的作用及其潜在分子机制。在高糖诱导衰老的心肌细胞和老年小鼠心脏中，H19水平显著升高。H19过表达增加了SA-β-gal阳性细胞数量以及衰老相关蛋白p53和p21的表达，而敲低H19则产生相反的效果。机制上，H19被证明是微小RNA-19a（miR-19a）的竞争性内源性RNA（ceRNA）：H19过表达下调miR-19a水平，而敲低H19则上调miR-19a。衰老心肌细胞和老年小鼠心脏中细胞因子信号转导抑制因子1（SOCS1）的表达显著增加。进一步实验确定SOCS1是miR-19a的下游靶点。H19通过靶向miR-19a上调SOCS1表达并激活p53/p2l通路，从而促进心肌细胞衰老。我们的研究结果表明，H19是心肌细胞中一种促进衰老的lncRNA，作为ceRNA靶向miR-19a/SOCS1/p53/p21通路。我们的研究揭示了心肌细胞衰老调控的分子机制，并为衰老相关心脏疾病的治疗提供了新靶点。
