Abstract Objective To explore the role and mechanism of different concentrations of resveratrol in the neurological function and the expression of HSP20 of cerebrally injured rats with ischemia-reperfusion. Methods We divided 150 healthy adult male SD rats by random number table into 5 groups: sham operation group, model group, low dose resveratrol (2.5 mg/kg) group, middle dose resveratrol (5 mg/kg) group, high dose resveratrol (10 mg/kg) group, with 30 rats in each group. MCAO surgery was performed in the rats to establish cerebral ischemia reperfusion model. Normal saline or different concentrations of resveratrol were intraperitoneally injected 20 minutes before the reperfusion. Neurological deficit scores were evaluated 6 h, 24 h, 48 h, 72 h, and 7 d after the operation. Cerebral infarction volume was calculated and compared among the five groups after TTC staining of brain tissues; tumor necrosis factor HSP20 around the area of ischemia brain tissues was detected by immunohistochemistry, and compared among the five groups. Results ①Comparison of neurological deficit scores: The intervention of different concentrations of resveratrol significantly improved the neurological deficit of rats, meanwhile, the higher the dose of resveratrol was, the more obvious the improvement of rats′ neurological deficit has got, which meant the improvement of high dose resveratrol group > middle dose resveratrol group > low dose resveratrol group (P<0.05), and it was in a dose-dependent manner. ②Comparison of cerebral infarction focus volumes: The intervention of different concentrations of resveratrol significantly reduced the cerebral infarction volumes of rats in different groups (P<0.05), and the higher the dose of resveratrol was, the larger the volume of reduced cerebral infarction was, which meant the reduced cerebral infarction volume of high dose resveratrol group>middle dose resveratrol group > low dose resveratrol group (P<0.05), and it was in a dose-dependent manner. ③Comparison of immunohistochemistry and western blots of tissues surrounding the cerebral ischemia areas: At different hours, the numbers of HSP20 positive cells in the brain tissues surrounding the rats′ cerebral ischemia area were: high dose resveratrol group> middle dose resveratrol group> low dose resveratrol group> model group> sham operation group (P<0.05), and the higher the dose of resveratrol was, the larger the number of HSP20 positive cells were (P<0.05), which was in a dose-dependent manner. The higher the dose of resveratrol was, the larger the expression quantity of HSP20 were (P<0.05), which was in a dose-dependent manner.Conclusion ① In the process of cerebral ischemia-reperfusion injury, resveratrol can reduce cerebral infarction volume and improve neurological deficit scores in a dose-dependent manner. It can also promote the expression of HSP20 through some kind of mechanism. ② The protective effect of resveratrol on cerebral ischemia reperfusion injury shows a significant dose-dependent manner.
|