Proventive effect and mechanism of microRNA-124-3p on hypoxia/reoxygenation injury in cardiomyocytes through targeting inhibiting RIPK1 expression

Wang Luqing; Jiang Hua; Zheng Sheng

doi:10.3969/j.issn.1674-4055.2019.11.11

Abstract：investigate the preventive effect of microRNA-124-3p (miR-124-3p) on hypoxia/reoxygenation (H/R) injury in cardiomyocytes through regulating receptor-interacting protein kinases1 (RIPK1). Methods Rat cardiomyocytes were divided randomly into Con group, H/R group, H/R+miR-124-3p group, H/R+miR-NC group H/R+si-RIPK1, H/R+siNC group, H/R+miR-124-3p+pcDNA group and H/R+miR-124-3p+pcDNA-RIPK1 group. The mRNA expressions of miR-124-3p and RIPK1 were detected by using qRT-PCR, and protein expression of RIPK1 was detected by using Western blotting assay. The targeting relationship between miR-124-3p and RIPK1 was detected by using dual-luciferase reporter gene assay. The apoptosis ability was detected by using flow cytometry (FCM), and protein expressions of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) were detected by using Western blotting assay. The activity of lactic dehydrogenase (LDH) and content of malondialdehyde (MDA) and superoxide dismutase (SOD) were detected. Results The expression of miR-124-3p was significantly lower (P<0.05) and mRNA and protein expressions of RIPK1 were significantly higher (P<0.05) in H/R group than those in Con group. LDH activity and levels of MDA and Bax were significantly higher (P<0.05), apoptosis rate was significantly higher (P<0.05), and levels of SOD and Bcl-2 were significantly lower (P<0.05) in H/R than those in Con group. The overexpression of miR-124-3p and inhibition of RIPK1 expression decreased apoptosis, LDH activity and levels of MDA and Bax, and increased levels of SOD and Bcl-2. The results of dual-luciferase reporter gene assay showed that RIPK1 was the targeting gene of miR-124-3p, and overexpression of RIPK1 reversed the damage effect of overexpression of miR-124-3p on H/R cardiomyocytes. Conclusion The overexpression of MiR-124-3p can relieve H/R injury in cardiomyocytes through down-regulating RIPK1 expression, and play a protective role to cardiomyocytes.