Effects of dihydromyricetin on myocardial oxidative damage in exhaustive exercise mice
Objective To investigate the effect of dihydromyricetin(DMY)on myocardial oxidative damage in exhaustive exercise mice.Methods C57BL/6 mice were divided into control group,model group,positive control group and low,medium and high dose experimental groups and with 10 mice in each group.Mice in control group and model group were intragastricated with distilled water;20,40 and 80 mg·kg-1 dihydromyricetin were given by gavage in low,medium and high dose experimental groups,while mice in positive control group were intragastricated with 100 mg·kg-1 Vitamin C once a day for 4 weeks.After administration,superoxide dismutase(SOD),malondialdehyde(MDA)and lactate dehydrogenase(LDH)were detected by the kit.The expression of nuclear factor E2-related factor 2(Nrf2)and heme oxygenase-1(HO-1)protein were detected by Western blot.Results SOD levels in control group,model group and low,medium,high dose experimental groups and positive control group were(57.81±6.92),(26.85±2.74),(33.68±4.52),(39.74±3.95),(48.97±4.26)and(39.22±3.54)U·mg-1;MDA were(4.72±0.36),(10.48±1.68),(8.75±0.82),(6.43±0.71),(5.11±0.48)and(6.36±0.64)nmol·mg-1;LDH were(268.71±23.94),(726.58±81.26),(621.32±47.59),(479.12±50.24),(337.91±34.99)and(486.15±50.98)U·L-1;Nrf2 protein expression were 0.75±0.06,0.19±0.02,0.30±0.04,0.47±0.05,0.63±0.06 and 0.49±0.06;the protein expression of HO-1 were 0.83±0.08,0.27±0.05,0.39±0.04,0.52±0.03,0.77±0.07 and 0.55±0.06,respectively.There were statistically significant differences between control group and model group(all P<0.05);there were statistically significant differences in the above indexes between model group and positive control group,low dose experimental group,medium dose experimental group,high dose experimental group(all P<0.05).Conclusion Dihydromyricetin can delay myocardial oxidative injury in exhaustive exercise mice,which may be related to Nrf2/HO-1 pathway.