白藜芦醇对阿尔茨海默病模型大鼠海马组织CaMKⅡ及PKA C-β基因表达的实验研究

Effect of resveratrol on the gene expressions of CaMKⅡ and PKA C-β in hippocampus of AD rat model

目的探讨白藜芦醇对阿尔茨海默病（Alzheimer′s disease,AD）模型大鼠海马组织中CaMKⅡ及PKA C-β基因表达的影响。方法鼠龄4~5个月健康雌性Wistar大鼠60只,按体质量随机分为假手术对照组（Sham control）、AD模型组（Model）、白藜芦醇低剂量（Res 20mg/kg）、中剂量（Res 40mg/kg）、高剂量（Res 80mg/kg）干预组及戊酸雌二醇组（ERT）。每组10只大鼠,对后5组大鼠行双侧卵巢摘除术,假手术组大鼠只切除双侧卵巢附近等体积的脂肪。术后一周开始给予干预,干预持续12周,取3只大鼠海马组织石蜡包埋切片进行HE染色检测海马组织神经细胞数量。利用Real-time PCR方法进行其余大鼠海马组织中CaMKⅡ及PKA C-β基因表达的检测。结果 （1）海马组织锥体细胞形态的改变：与假手术对照组比较,AD模型组大鼠海马锥体细胞排列稀疏、紊乱,细胞体积缩小,胞核固缩,胞浆浓缩、深染;白藜芦醇干预后细胞排列较整齐、均匀,结构清晰。（2）海马组织中CaMKⅡ及PKA C-β基因表达的改变：与对照组比较,模型组大鼠海马中CaMKⅡ及PKA C-β基因表达显著降低（P〈0.05）;与模型组比较,白藜芦醇干预组及ERT组大鼠海马中上述两个基因表达显著升高（P〈0.05）。结论白藜芦醇可以升高AD模型大鼠海马组织中CaMKⅡ及PKA C-β基因的表达,可能是其改善AD模型大鼠记忆的机制之一。

Objective To explore the effect of resveratrol（Res）on the gene expressions of CaMK Ⅱ and PKA C-βin hippocampus of AD rats model. Methods AD rat model was established by ovariectomized combined with D-galactose injection.Res was intragastric administrated to rats by 20 mg/kg,40 mg/kg and80mg/kg,respectively for 12 weeks.Rats in estradiol group was treated with estradiol 0.8mg/kg and one group of rats served as sham controls.There were 10 rats in each group.Twelve weeks later,3rats in each group were randomly selected in vivo cardiac perfusion,the hippocampus was removed,formalin fixed,paraffin embedded and serial sections were prepared by HE staining.Gene expressions of CaMKⅡand PKA C-βin hippocampus of the rest 7rats in each group were determined by real-time PCR. Results HE staining showed that hippocampal pyramidal cells of rats with AD arranged in sparse and disordered manner,cells shrink with condensed nuclear and cytoplasm,while the morphology and structure of cells turned to normal after being treated with resveratrol.Compared with sham control rats,the gene expression levels of CaMKⅡand PKA C-βin hippocampus of AD rats decreased significantly（P〈0.05）.Meanwhile,compared with AD rats,CaMKⅡand PKA C-βlevels in hippocampus of rats treated with 40 and 80mg/kg Res increased significantly（P〈0.05）. Conclusions Resveratrol may improve the memory of AD rat model by up-regulating CaMKⅡ and PKA C-βgenes in hippocampus.