小檗碱抑制JAK2/STAT3信号通路改善糖尿病大鼠前额叶皮层神经元损伤

Berberine Improves Neuronal Cell Damage in Prefrontal Cortex of Diabetic Rats by Lnbibiting JAK2/STAT3 Signaling Pathway

目的探讨小檗碱(BBR)通过介导JAK2/STAT3信号通路对糖尿病大鼠前额叶皮层神经元损伤的作用。方法将48只8周龄的雄性Wistar大鼠分为对照组(Nor组)、糖尿病组(DM组)、小檗碱治疗组(BBR组)、二甲双胍治疗组(Met组)4组。DM模型通过给予高脂高糖饲料并联合尾静脉注射链脲佐菌素(25mg/kg)诱导造模,之后将小檗碱187.75mg/(kg·d)和二甲双胍184mg/(kg·d)以灌胃方式给药治疗,连续给药6周。取材后通过HE染色观察各组大鼠前额叶皮层区神经元形态的变化;通过免疫组化观察各组大鼠前额叶皮层区小胶质细胞的活化程度;通过Western blot法检测各组大鼠前额叶皮层中p JAK2/JAK2与p STAT3/STAT3的蛋白表达水平;通过免疫荧光检测各组大鼠前额叶皮层区Caspase 3的蛋白表达水平。结果与Nor组相比,DM组大鼠的前额叶皮层区神经元发生了变性,小胶质细胞过度活化,Iba 1蛋白表达水平明显升高,JAK2/STAT3信号通路显著激活和Caspase 3蛋白荧光强度明显增强;经BBR和Met治疗后,糖尿病大鼠的前额叶皮层区神经元均有不同程度的改善,小胶质细胞的活化程度、Iba 1蛋白的表达水平、JAK2/STAT3信号通路激活程度和Caspase 3蛋白荧光强度均明显降低。结论小檗碱可能通过抑制JAK2/STAT3信号通路来降低小胶质细胞的活化程度,从而减少炎症反应和细胞凋亡,最终改善糖尿病大鼠前额叶皮层中神经元损伤。

Objective This study was designed to explore the role of berberine in the damage of prefrontal cortex neurons in diabetic rats by mediating JAK2/STAT3 signaling pathway.Methods Forty eight male Wistar rats with eight week old were divided into control group(Nor group),diabetes group(DM group),berberine treatment group(BBR group),metformin treatment group(Met group).The DM model was induced by administering high fat and high sugar feed combined with tail vein injection of streptozotocin(25mg/kg),followed by oral administration of berberine[187.75mg/(Kg·d)]and metformin[184mg/(Kg·d)]for 6 weeks.After sampling,HE staining was used to observe the structural changes of neurons in the prefrontal cortex of rats in each group.Immunohistochemistry was used to observe the activation of microglia in prefrontal cortex.Western blot method was used to detect the protein expression levels of p JAK2/JAK2 and p STAT3/STAT3 in the prefrontal cortex of rats in each group.Immunofluorescence was used to detect the protein expression level of Caspase 3 in the prefrontal cortex of rats in each group.Results Compared with Nor group,neurons in the prefrontal cortex of DM group were denaturated,microglia were over activated,the expression level of Iba 1 protein was significantly increased,JAK2/STAT3 signaling pathway was significantly activated and the fluorescence intensity of Caspase 3 protein was significantly enhanced.After BBR and Met treatment,the neurons in the prefrontal cortex of diabetic rats were improved to varying degrees,and the activation degree of microglia,the expression level of Iba 1 protein,the activation degree of JAK2/STAT3 signaling pathway and the fluorescence intensity of Caspase 3 protein were significantly reduced.Conclusion Berberine may reduce the activation of microglia by inhibiting JAK2/STAT3 signaling pathway,thereby reducing inflammatory reaction and apoptosis,and ultimately improving neuronal damage in the prefrontal cortex of diabetic rats.