Xia Li1, Xiaoli Kang1, Yali Di1, Shuxian Sun1, Liming Yang1, Bin Wang1, Zheng Ji2. 1. Department I of Cardiology, Tangshan Gongren Hospital, No. 27 Wenhua Road, Tangshan, 063000, Hebei, China. 2. Department I of Cardiology, Tangshan Gongren Hospital, No. 27 Wenhua Road, Tangshan, 063000, Hebei, China. mnradc@163.com.
Abstract
BACKGROUND: Aberrant expression of circular RNA (circRNA) has been demonstrated to be related to atherosclerosis (AS) formation. However, the mechanism of circCHMP5 (also known as hsa_circ_0003575) in AS formation remains unclear. METHODS: Oxidized low-density lipoprotein (ox-LDL) was used to treat human umbilical vein endothelial cells (HUVECs) to construct a cell injury model. The expression level of circCHMP5, miR-532-5p, and Rho-associated protein kinase 2 (ROCK2) was measured using quantitative real-time PCR. Cell cycle, apoptosis, proliferation, and angiogenesis were determined by flow cytometry, 5-ethynyl-2'-deoxyuridine (EdU) assay, and tube formation assay. In addition, the protein expression of apoptosis markers, inflammation factors, and ROCK2 was detected by western blot analysis. The interaction between miR-532-5p and circCHMP5 or ROCK2 was assessed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. RESULTS: Our results indicated that circCHMP5 was overexpressed in ox-LDL-induced HUVECs. CircCHMP5 knockdown promoted cell cycle, proliferation, and angiogenesis while inhibiting apoptosis and inflammation in ox-LDL-induced HUVECs. MiR-532-5p could be sponged by circCHMP5, and its inhibitor reversed the negative regulation of si-circCHMP5 on ox-LDL-induced HUVECs injury. ROCK2, a target of miR-532-5p, reversed the inhibition effect of miR-532-5p on ox-LDL-induced HUVECs injury. Furthermore, we confirmed that circCHMP5 upregulated ROCK2 by sponging miR-532-5p. CONCLUSION: To sum up, our data showed that circCHMP5 regulated the miR-532-5p/ROCK2 axis to accelerate ox-LDL-induced HUVECs injury, confirming that circCHMP5 might be a potential target for AS treatment.
BACKGROUND: Aberrant expression of circular RNA (circRNA) has been demonstrated to be related to atherosclerosis (AS) formation. However, the mechanism of circCHMP5 (also known as hsa_circ_0003575) in AS formation remains unclear. METHODS: Oxidized low-density lipoprotein (ox-LDL) was used to treat human umbilical vein endothelial cells (HUVECs) to construct a cell injury model. The expression level of circCHMP5, miR-532-5p, and Rho-associated protein kinase 2 (ROCK2) was measured using quantitative real-time PCR. Cell cycle, apoptosis, proliferation, and angiogenesis were determined by flow cytometry, 5-ethynyl-2'-deoxyuridine (EdU) assay, and tube formation assay. In addition, the protein expression of apoptosis markers, inflammation factors, and ROCK2 was detected by western blot analysis. The interaction between miR-532-5p and circCHMP5 or ROCK2 was assessed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. RESULTS: Our results indicated that circCHMP5 was overexpressed in ox-LDL-induced HUVECs. CircCHMP5 knockdown promoted cell cycle, proliferation, and angiogenesis while inhibiting apoptosis and inflammation in ox-LDL-induced HUVECs. MiR-532-5p could be sponged by circCHMP5, and its inhibitor reversed the negative regulation of si-circCHMP5 on ox-LDL-induced HUVECs injury. ROCK2, a target of miR-532-5p, reversed the inhibition effect of miR-532-5p on ox-LDL-induced HUVECs injury. Furthermore, we confirmed that circCHMP5 upregulated ROCK2 by sponging miR-532-5p. CONCLUSION: To sum up, our data showed that circCHMP5 regulated the miR-532-5p/ROCK2 axis to accelerate ox-LDL-induced HUVECs injury, confirming that circCHMP5 might be a potential target for AS treatment.