Nrf2激动剂EGCG对糖尿病伤口愈合障碍的治疗作用研究

Therapeutic effect of Nrf2 agonist EGCG on diabetic wound healing disorders

目的:建立糖尿病及糖尿病伤口愈合障碍动物模型,研究EGCG对糖尿病伤口愈合障碍的治疗作用,探讨相关的免疫学机制和分子生物学机制。方法:腹腔注射STZ,检测空腹血糖,建立糖尿病小鼠模型。高糖高脂饮食长期饲养,使其处于稳定的糖尿病状态。人工制造皮肤创口,动态观察伤口愈合率,建立糖尿病伤口愈合障碍动物模型。期间,按照分组要求,应用EGCG进行药物治疗,根据伤口愈合率研究治疗效果。治疗期满,取创面皮肤进行相关指标检测。应用Western blot技术检测Nrf2、HO-1、NQO1、ICAM-1、VCAM-1和Caspase12等蛋白质相对表达量;免疫组化技术检测3-NT;对各检测指标进行统计学分析,阐述EGCG治疗糖尿病伤口愈合障碍的作用机制。结果:糖尿病组伤口愈合率明显低于正常对照组(P<0.01),证明糖尿病伤口愈合障碍建模成功;糖尿病小鼠EGCG治疗组的伤口愈合率明显高于非治疗组(P<0.05)。糖尿病组的Nrf2、HO-1和NQO1蛋白表达量均低于正常对照组(P<0.05);ICAM-1、VCAM-1和Caspase12等蛋白表达量均高于正常对照组(P<0.05)。糖尿病小鼠中,EGCG治疗组Nrf2、HO-1和NQO1蛋白表达量均高于其非治疗组(P<0.05);ICAM-1、VCAM-1和Caspase12等蛋白表达量均低于其非治疗组(P<0.05)。免疫组化实验检测3-NT结果显示,糖尿病组3-NT阳性率明显高于Control组,证明糖尿病机体皮肤伤口处于较高水平的氧化应激状态。糖尿病小鼠EGCG治疗组3-NT阳性率明显少于其非治疗组(P<0.05)。结论:Nrf2是糖尿病并发症的关键保护性因子;上调机体Nrf2表达可有效减轻糖尿病并发症;EGCG作为Nrf2激动剂具有对抗糖尿病引起的氧化应激、炎症和细胞凋亡的作用,对DNHW有明显的治疗作用。

Objective:To establish an animal model of diabetes mellitus and diabetic wound healing disorder,study the therapeutic effect of EGCG on diabetic wound healing disorder,and explore the relevant immunological and molecular biological mechanisms.Methods:STZ was injected intraperitoneally to detect fasting blood glucose and establish a mouse model of diabetes.The mice were fed a high-sugar and high-fat diet for a long time to keep them in a stable state of diabetes.Skin wounds were made artificially,the wound healing rate was dynamically observed,and an animal model of diabetic wound healing disorder was established.During the treatment,EGCG was applied for drug treatment of mice according to the grouping requirements,and the treatment effect was studied according to the wound healing rate.At the expiration of the treatment period,the wound skin was taken for relevant index detection.Western blot was used to detect the relative expression of proteins such as Nrf2,HO-1,NQO1,ICAM-1,VCAM-1,and Caspase12.Immunohistochemistry was used to detect 3-NT.The statistical analysis of each detection index was performed to explain the mechanism of EGCG in the treatment of diabetic wound healing disorders.Results:The wound healing rate of the diabetic group was significantly lower than that of the normal control group(P<0.01),indicating that the modeling of diabetic wound healing disorder was successful.The wound healing rate of diabetic mice treated with EGCG was significantly higher than that of non-treated mice(P<0.05),proving that EGCG had a therapeutic effect on diabetic wound healing disorders.The protein expressions of Nrf2,HO-1 and NQO1 in the diabetic group were lower than those in the normal control group(P<0.05).The expression levels of ICAM-1,VCAM-1 and Caspase12 were higher than that of the control group(P<0.05).In diabetic mice,Nrf2,HO-1 and NQO1 protein expressions in the EGCG-treated group were higher than those in the non-treated group(P<0.05).The expression levels of ICAM-1,VCAM-1 and Caspase12 were all lower than that of the non-treatment group(P<0.05).Immunohistochemical test showed that the 3-NT positive rate in the diabetes group was significantly higher than that in the control group,indicating that the skin wound of the diabetic body was under a higher level of oxidative stress.Diabetic mice in the EGCG-treated group had significantly less 3-NT positive regions than those in the non-treated group(P<0.05).Conclusion:Nrf2 is a key protective factor for diabetic complications.Upregulated Nrf2 expression can effectively reduce diabetic complications.As a Nrf2 agonist,EGCG,has the effect of combating oxidative stress,inflammation and apoptosis caused by diabetes,and has an obvious therapeutic effect on DNHW.