Neuroprotective effects of genistein on SH-SY5Y cells overexpressing A53T mutant α-synuclein

Genistein, a potent antioxidant compound, protects dopaminergic neurons in a mouse model of Parkinson＇s disease. However, the mecha- nism underlying this action remains unknown. This study investigated human SH-SYSY cells overexpressing the A53T mutant of α-synuclein. Four groups of cells were assayed： a control group （without any treatment）, a genistein group （incubated with 20 μM genistein）, a rote- none group （treated with 50 μM rotenone）, and a rotenone ＋ genistein group （incubated with 20 μM genistein and then treated with 50μM rotenone）. A lactate dehydrogenase release test confirmed the protective effect of genistein, and genistein remarkably reversed mitochondrial oxidative injury caused by rotenone. Western blot assays showed that BCL-2 and Beclin ! levels were markedly higher in the genistein group than in the rotenone group. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling revealed that genistein inhibited rotenone-induced apoptosis in SH-SYSY cells. Compared with the control group, the expression of NFE2L2 and HMOX1 was significantly increased in the genistein ＋ rotenone group. However, after treatment with estrogen receptor and NFE2L2 channel blockers （ICI-182780 and ML385, respectively）, genistein could not elevate NFE2L2 and HMOX1 expression. ICI-182780 effectively prevented genistein-mediated phosphorylation of NFE2L2 and remarkably suppressed phosphorylation of AKT, a protein downstream of the estrogen receptor. These findings confirm that genistein has neuroprotective effects in a cell model of Parkinson＇s dis- ease. Genistein can reduce oxidative stress damage and cell apoptosis by activating estrogen receptors and NFE2L2 channels.

Exendin-4 inhibits high-altitude cerebral edema by protecting against neurobiological dysfunction

The anti-inflammatory and antioxidant effects of exendin-4（Ex-4） have been reported previously.However,whether（Ex-4） has anti-inflammatory and antioxidant effects on high-altitude cerebral edema（HACE） remains poorly understood.In this study,two rat models of HACE were established by placing rats in a hypoxic environment with a simulated altitude of either 6000-or 7000-m above sea level（MASL） for 72 hours.An altitude of 7000 MASL with 72-hours of hypoxia was found to be the optimized experimental paradigm for establishing HACE models.Then,in rats where a model of HACE was established by introducing them to a 7000 MASL environment with 72-hours of hypoxia treatment,2,10 and,100 μg of Ex-4 was intraperitoneally administrated.The open field test and tail suspension test were used to test animal behavior.Routine methods were used to detect change in inflammatory cells.Hematoxylin-eosin staining was performed to determine pathological changes to brain tissue.Wet/dry weight ratios were used to measure brain water content.Evans blue leakage was used to determine blood-brain barrier integrity.Enzyme-linked immunosorbent assay（ELISA） was performed to measure markers of inflammation and oxidative stress including superoxide dismutase,glutathione,and malonaldehyde values,as well as interleukin-6,tumor necrosis factor-alpha,cyclic adenosine monophosphate levels in the brain tissue.Western blot analysis was performed to determine the levels of occludin,ZO-1,SOCS-3,vascular endothelial growth factor,EPAC1,nuclear factor-kappa B,and aquaporin-4.Our results demonstrate that Ex-4 preconditioning decreased brain water content,inhibited inflammation and oxidative stress,alleviated brain tissue injury,maintain blood-brain barrier integrity,and effectively improved motor function in rat models of HACE.These findings suggest that Ex-4 exhibits therapeutic potential in the treatment of HACE.