艳山姜挥发油调控p62/Keap1/Nrf2信号改善糖尿病小鼠胰腺损伤

The protective effect of essential oil from fructus alpiniae zerumbet on T2DM induced pancreatic injury in mice based on p62/Keap1/Nrf2 signaling pathway

目的探讨艳山姜挥发油(essential oils from Fructus Alpiniae zerumbet,EOFAZ)对2型糖尿病小鼠胰腺损伤的保护作用及作用机制。方法高糖高脂(HFS)饲料饲养C57 BL/6小鼠形成胰岛素抵抗,腹腔注射链脲佐菌素(STZ,120 mg·kg^(-1))建立2型糖尿病小鼠模型,将糖尿病小鼠随机分成糖尿病组(DM)、DM+EOFAZ低剂量组(90 mg·kg^(-1))、DM+EOFA高剂量组(180 mg·kg^(-1))、DM+二甲双胍组(250 mg·kg^(-1)),另取健康小鼠随机分为正常对照组、EOFAZ毒性组(180 mg·kg^(-1))。EOFAZ组、二甲双胍组分别灌胃EOFAZ和二甲双胍的同时,正常组和DM组以等体积生理盐水灌胃,每日一次,连续灌胃8周后,血糖仪检测血糖。采用HE染色对胰腺进行病理形态学观察;蛋白免疫印迹法分析胰腺组织中p62、Keap1、Nrf2、HO-1、Bcl-2及Bax的表达。免疫组织化学分析胰腺组织中Nrf2的表达水平。结果与模型组相比较,给予EOFAZ后,可明显改善胰岛的病理形态;明显下调Keap1、Bax蛋白表达,并上调p62、Nrf2、Ho-1及Bcl-2蛋白的表达(P<0.05)。结论EOFAZ对糖尿病诱导的胰腺损伤具有明显的改善作用,其作用可能与激活p62/Keap1/Nrf2信号通路,抑制凋亡信号相关。

Aim To investigate the protective effect of essential oil from Fructus Alpiniae Zerumbet(EOFAZ)on type 2 diabetes-induced pancreatic injury in mice and its mechanism.Methods After C57 BL/6 mice fed with high-sugar and high-fat(HFS)feed developed insulin resistance,streptozotocin(STZ,120 mg·kg^(-1))was injected intraperitoneally to establish type 2 diabetes model(DM),then DM mice were randomly divided into:diabetes group(DM),EOFAZ low-dose group(90 mg·kg^(-1)),EOFAZ high-dose group(180 mg·kg^(-1)),and metformin group(250 mg·kg^(-1)).Healthy mice were randomly divided into:normal group and EOFAZ toxicity group(180 mg·kg^(-1)).EOFAZ group and metformin group were given EOFAZ and metformin,while normal group and DM group were given an equal volume of normal saline once daily.After eight weeks of continuous intragastric administration,the mice were sacrificed,and the blood was collected to measure fasting blood glucose.HE staining was used to observe the pathological morphology of the pancreas;Western blot was used to analyze the expression of p62,Kelch-like epichlorohydrin-related protein 1(Keap1),nuclear factor E2-related factor 2(Nrf2),and heme oxygenase-1(HO-1),anti-apoptotic protein(Bcl-2)and pro-apoptotic protein(Bax).Immunohistochemistry was used to analyze the expression of Nrf2 in pancreatic tissue.Results Compared with DM group,after administration of EOFAZ,the pathological morphology of pancreas was significantly improved;Keap1,Bax protein expressions were significantly down-regulated and p62,Nrf2,Ho-1,Bcl-2 protein expressions were up-regulated(P<0.05).Conclusions EOFAZ has a significant improvement effect on pancreatic injury induced by diabetes,and its effect may be related to the activation of p62/Keap1/Nrf2 to regulate apoptotic response.