白藜芦醇对急性低压缺氧诱导的大鼠视网膜损伤的保护作用

目的　探讨白藜芦醇对急性低压缺氧诱导的大鼠视网膜损伤的保护作用及机制。方法　将72只健康SD大鼠随机分成3组:常氧对照组、低氧模型组、低氧+白藜芦醇（resveratrol，RES）干预组（RES干预组）。常氧对照组大鼠在常氧环境下喂养，低氧模型组及RES干预组大鼠置于低压氧舱内（模拟5000 m的海拔高度）喂养，RES干预组每日并给予腹腔注射30 mg·kg^-1 RES 1次。各组大鼠在不同处理7 d后剥离视网膜，免疫组织化学法观察大鼠视网膜组织中胶质纤维酸性蛋白（glial fibrillary acidic protein，GFAP）和缺氧诱导因子-1（hypoxia-inducible factor-1，HIF-1）的表达，RT-PCR检测核转录因子-kappaB（nuclear factor-kappa B，NF-κB）和脑源性神经营养因子（brain-derived neurotrophic factor，BDNF）mRNA的表达。结果　低氧模型组大鼠视网膜GFAP与HIF-1的表达较常氧对照组增加，BDNF mRNA（2.627±0.633）和NF-κB mRNA（1.712±0.198）的相对表达量较常氧对照组（2.000±0.518、1.053±0.483）上调（P= 0.013、0.008）。与低氧模型组对比，RES干预组视网膜受损程度减轻，GFAP与HIF-1的表达减少，BDNF mRNA相对表达量（2.053±0.938）显著下调，差异有统计学意义（P=0.024），而NF-κB mRNA相对表达量（1.481±0.397）与低氧模型组相比，差异无统计学意义（P=0.455）。结论　RES对高海拔缺氧诱导的视网膜损伤有保护作用，其机制可能与调节GFAP、HIF-1、BDNF以及NF-κB的表达有关。

Protective effects of resveratrol on acute hypobaric hypoxia-induced rat retinal impairment

Objective　To investigate the protective effects of resveratrol （RES） on rat retinal impairment induced by acute hypobaric hypoxia as well as the mechanism involved in the pathological process.Methods　Seventy-two Sprague-Dawley （SD） rats were randomly divided into control group，hypoxic model group，and RES intervention group．The control group was housed in normoxic condition.The hypoxic model group and the RES intervention group were maintained at a low-pressure oxygen cabin，as similar pressure as 5000 m above sea level.RES group was given intraperitoneal injection （30 mg·kg^-1，once a day）.Retinal tissue was obtained after rats were treated after 7 days.Expression levels of glial fibrillary acidic protein （GFAP） and hypoxia-inducible factor-1 （HIF-1） in retina were examined by immunohistochemistry.Nuclear factor-kappaB （NF-κB） and brain-derived neurotrophic factor （BDNF） mRNA expression levels were determined by quantitative real time PCR.Results　Increased immunohistochemical expression levels of GFAP and HIF-1 were found in the retinas of the hypoxic model group as compared to the control group.Hypobaric hypoxia upregulated the relative expression of BDNF （2.627±0.633） and NF-κB mRNA （1.712±0.198），compared with controls （2.000±0.518，1.053±0.483），respectively （P=0.013，0.008）.RES mitigated the retinal damage by the down-regulation of GFAP and HIF-1 expression in rat retinas；meanwhile，the administration of RES also down regulated mRNA level of BDNF （2.053±0.938） as compared to hypoxic model group，and there was a significant difference （P=0.024）.NF-κB mRNA expression （1.481±0.397） decreased in the RES-treated group，but no significant difference was seen when compared to hypoxic model group （P=0.455）.Conclusion　The intervention of RES plays a protective role in high altitude hypoxia-induced retinal damage through modulating the gene expression of GFAP，HIF-1，BDNF and NF-κB.