Effects of miRNA-499a-5p targeting CD38 on hydrogen peroxide-induced cardiomyocyte injury and the possible mechanism / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To investigate the effects of miRNA-499a-5p targeting CD38 on cardiomyocyte injury induced by hydrogen peroxide (H 2O 2) and the possible mechanism. Methods:H9c2 cardiomyocytes were cultured in vitro and induced with H 2O 2 to establish the cardiomyocyte injury model. Four groups including control, H 2O 2, H 2O 2+ negative control (NC) and H 2O 2+ miRNA-499a-5p groups were set up. Real-time quantitative PCR (RT-qPCR) and Western blot were used to detect the expression of miRNA-499a-5p and CD38 in cardiomyocytes, respectively. MTT assay was used to measure the survival rates of cardiomyocytes. The levels of reactive oxygen species (ROS) and the activity of lactate dehydrogenase (LDH) were analyzed with test kits. Annexin V-FITC/PI double staining method was used to detect the apoptosis rates of cardiomyocytes. Western blot was used to detect the expression of B-cell lymphoma/leukemia-2 (Bcl-2), Bcl-2-related X protein (Bax), phosphoinositide 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt) and phosphorylated Akt (p-Akt). Dual luciferase reporter assay was used to detect the targeting relationship between miRNA-499a-5p and CD38. Results:Compared with the control group, the expression of miRNA-499a-5p, Bcl-2, p-PI3K and p-Akt and the survival rate of cardiomyocytes were significantly reduced in the H 2O 2 group ( P<0.05), while the expression of CD38 and Bax, ROS level, LDH activity and the apoptosis rate were significantly increased ( P<0.05). Compared with the H 2O 2 group, the expression of miRNA-499a-5p, Bcl-2, p-PI3K and p-Akt and the survival rate of cardiomyocytes were significantly increased in the H 2O 2+ miRNA-499a-5p group ( P<0.05), while the expression of CD38 and Bax, ROS level, LDH activity and the apoptosis rate were significantly decreased ( P<0.05). Dual luciferase reporter assay confirmed that CD38 was a target gene of miRNA-499a-5p. Conclusions:miRNA-499a-5p could alleviate H 2O 2-induced cardiomyocyte injury by inhibiting the expression of CD38 and the PI3K/Akt signaling pathway might be involved.