The Effect Of Genipin On Oxidative Stress Injury In H9c2 Cell Line Subjected To Hypoxia/reoxygenation

OBJECTIVE To investigate the protective effect and mechanism of genipin on oxidative stress injury in H9c2 cell line subjected to hypoxia/reoxygenation.METHODS For mimicking myocardial ischemia/reperfusion(I/R) injury, H9c2 cells were cultured in vitro and established hypoxia/reoxygenation induced oxidative stress injury model. H9c2 cells were divided into six groups: Control group, H/R group, H/R+0.5μmol·L-1 Genipin group, H/R+1.25μmol·L-1 Genipin group, H/R+2.5μmol·L-1 Genipin group and H/R+10μmol·L-1 Genipin group. Cell viability was detected by cell counting kit-8 assay(CCK-8). The levels of lactate dehydrogenase(LDH), intracellular total superoxide dismutase(SOD) and malondialdehyde(MDA) were assessed using microplate reader. Confocal laser scanning microscope was performed to examine the production of reactive oxygen species and reactive nitrogen species(ROS and RNS) and the level of mitochondrial calcium([Ca2+]m) as well as the depolarization ratio of mitochondrial membranes potential(ΔΨm). The protein expression of cytochrome-c was detected by western-blot.RESULTS Comparing to Control group, the cell viability of H/R group was significantly decreased(P<0.01). Low concentration(1.25μmol·L-1~40μmol·L-1) of genipin could improve cell viability exposed to H/R treatment(P<0.05), on the contrary, high concentration(80μmol·L-1~320μmol·L-1) of genipin remarkably reduced the cell viability(P<0.05). In compared with H/R group, the levels of LDH release, MDA production, ROS and RNS production, the level of [Ca2+]m, depolarization ratio of ΔΨm and the protein expression of cytochrome-c in H/R+(1.25μmol·L-1~10μmol·L-1) genipin groups were notably lessened, while the level of SOD was increased(P<0.01 or P<0.05).CONCLUSIONS Genipin could protect H/R-induced H9c2 cell injury. The mechanism might be connected with anti-oxidative stress and improving mitochondrial dysfunction.