[Sanshentongmai Mixture Improves Oxidative Damage in Rat Cardiomyocytes H9C2 via Upregulation of microRNA-146a].

Abstract

Objective: To investigate the effect of Sanshentongmai (SSTM) mixture on the regulation of oxidative damage to rat cardiomyocytes (H9C2) through microRNA-146a and its mechanism.

Methods: H9C2 were cultured in vitro, H₂O₂ was used as an oxidant to create an oxidative damage model in H9C2 cells. SSTM intervention was administered to the H9C2 cells. Then, the changes in H₂O₂-induced oxidative damage in H9C2 cells and the expression of microRNA-146a were observed to explore the protective effect of SSTM on H9C2 and its mechanism. H9C2 cells cultured i n vitro were divided into 3 groups, including a control group, a model group of H₂O₂-induced oxidative damage (referred to hereafter as the model group), and a group given H₂O₂ modeling plus SSTM intervention at 500 μg/L for 72 h (referred to hereafter as the treatment group). The cell viability was measured by CCK8 assay. In addition, the levels of N-terminal pro-brain natriuretic peptide (Nt-proBNP), nitric oxide (NO), high-sensitivity C-reactive protein (Hs-CRP), and angiotensin were determined by enzyme-linked immunosorbent assay (ELISA). The expression level of microRNA-146a was determined by real-time PCR (RT-PCR).

Result: H9C2 cells were pretreated with SSTM at mass concentrations ranging from 200 to 1500 μg/L. Then, CCK8 assay was performed to measure cell viability and the findings showed that the improvement in cell proliferation reached its peak when the mass concentration of SSTM was 500 μg/L, which was subsequently used as the intervention concentration. ELISA was performed to measure the indicators related to heart failure, including Nt-proBNP, NO, Hs-CRP, and angiotensin Ⅱ. Compared with those of the control group, the expressions of Nt-proBNP and angiotensin Ⅱ in the treatment group were up-regulated (P<0.05), while the expression of NO was down-regulated (P<0.05). There was no significant difference in the expression of Hs-CRP between the treatment group and the control group. These findings indicate that SSTM could effectively ameliorate oxidative damage in H9C2 rat cardiomyocytes. Finally, according to the RT-PCR findings for the expression of microRNA-146a in each group, H₂O₂ treatment at 15 μmol/L could significantly reduce the expression of microRNA-146a, and the expression of microRNA-146a in the treatment group was nearly doubled compared with that in the model group. There was no significant difference between the treatment group and the control group.

Conclusion: SSTM can significantly resist the H₂O₂-induced oxidative damage of H9C2 cells and may play a myocardial protective role by upregulating microRNA-146a.