Berberine alleviates myocardial ischemia-reperfusion injury by inhibiting inflammatory response and oxidative stress: the key function of miR-26b-5p-mediated PTGS2/MAPK signal transduction

Context Berberine has myocardial protective effects. Objectives The protective effects of berberine on heart ischemia-reperfusion (I/R) injury were explored. Materials and methods Human cardiomyocytes were divided into control group, oxygen-glucose deprivation/re-oxygen (OGD/R) (2 h OGD with 24 h reoxygenation) group, OGD/R + low group (5 mu M berberine for 24 h) and OGD/R + high group (10 mu M berberine for 24 h). Twenty-four Wistar rats were divided into sham group, I/R group (45 min occlusion with 2 h reperfusion), I/R + berberine group (50 mg/kg berberine 1 h before I/R surgery) and I/R + berberine + antagomir (intraperitoneally injected with miR-26b-5p antagomir). MicroRNA profile, effects of berberine on I/R or OGD/R-induced injuries, and the role of miR-26b-5p in the function of berberine were explored. Results OGD/R treatment suppressed viability (0.41 +/- 0.05 vs. 0.87 +/- 0.13, p< 0.05), while induced apoptosis (6.6 +/- 1.0% vs. 26.3 +/- 4.8%, p< 0.05) in cardiomyocytes, which was restored by berberine (viability: 0.64 +/- 0.01 for 5 mu M and 0.72 +/- 0.01 for 10 mu M, p< 0.05; apoptosis: 10.9 +/- 2.2 for 5 mu M and 7.9 +/- 1.3 for 10 mu M). Berberine induced miR-26b-5p and inhibited PTGS2/MAPK pathway. MiR-26b-5p inhibition counteracted the protective function of berberine. In rats, berberine (50 mg/kg) improved heart histological structure and suppressed inflammatory response, which was impaired by miR-26b-5p inhibition. Discussion and conclusions Berberine exerted anti-I/R function in heart by inducing miR-26b-5p and suppressing the PTGS2/MAPK pathway. These data promote the application of berberine as an anti-I/R agent.