ABSTRACT
The aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) contribute to the development of neointima formation in vascular restenosis. This study aims to explore the function of the long noncoding RNA H19 in neointima formation. A mouse carotid ligation model was established, and human vascular smooth muscle cells (VSMCs) were used as a cell model. lncRNA H19 overexpression promoted VSMC proliferation and migration. Moreover, miR-125a-3p potentially bound to lncRNA H19, and Fms-like tyrosine kinase-1 (FLT1) might be a direct target of miR-125a-3p in VSMCs. Upregulation of miR-125a-3p alleviated lncRNA H19-enhanced VSMC proliferation and migration. Furthermore, rescue experiments showed that enhanced expression of miR-125a-3p attenuated lncRNA H19-induced FLT1 expression in VSMCs. In addition, the overexpression of lncRNA H19 significantly exacerbated neointima formation in a mouse carotid ligation model. In summary, lncRNA H19 stimulates VSMC proliferation and migration by acting as a competing endogenous RNA (ceRNA) of miR-125a-3p. lncRNA H19 may be a therapeutic target for restenosis.
ABSTRACT
ABSTRACT: The high level of oxidative stress induced by angiotensin II (AngII) is the main pathophysiological process that promotes the proliferation and migration of vascular smooth muscle cells (VSMCs) and induces vascular remodeling. LncRNA Metastasis-related lung adenocarcinoma transcript 1 (MALAT1) has been determined to play an important role in the modulation of oxidative stress and the development of cardiovascular diseases. Nevertheless, the function and underlying mechanism of MALAT1 in restenosis induced by hypertensive angioplasty remain unclear. AngII increased the expression of MALAT1 in VSMCs. We found that anti-sense oligonucleotide lncRNA MALAT1 (ASO-MALAT1) could inhibit AngII induced reactive oxygen species (ROS) production and VSMCs proliferation and migration by inducing the expression of glutathione peroxidase 4 (GPX4), which can be reversed by siRNA-GPX4. And GPX4 overexpression can inhibit the proliferation and migration of VSMCs induced by AngII. In addition, we found that the process by which MALAT1 knockdown induces GPX4 expression involves nuclear factor erythrocyte 2 related factor 2 (Nrf2). Overexpression of Nrf2 can increase the expression of GPX4, and down-regulation of GPX4 by ML385 (Nrf2 inhibitor) blocked the protective effect of ASO-MALAT1 on AngII-induced proliferation and migration of VSMCs. Ferrostatin-1 (Fer-1, ip 5mg/kg per day for 2 weeks), a GPX4 agonist, significantly inhibited neointimal formation in spontaneously hypertensive rat (SHR) by the inhibition of oxidative stress. In conclusion, these data imply that ASO-MALAT1 suppresses the AngII-induced oxidative stress, proliferation and migration of VSMCs by activating Nrf2/GPX4 antioxidant signaling. GPX4 may be a potential target for the therapeutic intervention of hypertensive vascular restenosis.