当归多糖对D-半乳糖致衰老模型小鼠的影响

Effect of angelica sinensis polysaccharide on D-galactose-induced aging model mice

目的探究当归多糖(ASP)通过调节c-Jun氨基末端激酶(JNK)/转录因子NF-E2相关因子2(Nrf2)/抗氧化反应元件(ARE)(JNK/Nrf2/ARE)信号通路对D-半乳糖致衰老模型小鼠的影响。方法用皮下注射D-半乳糖溶液125 mg·kg^(-1),每日1次,连续6周,建立小鼠衰老模型;ICR小鼠120只,随机分为对照组、模型组及低、高剂量实验组,各30只。造模成功后,低、高剂量实验组小鼠分别每日腹腔注射100,200 mg·kg^(-1)ASP,对照组与模型组注射等量生理盐水,连续干预4周。用试剂盒测定脑组织总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量;用蛋白质免疫印迹法检测脑组织中JNK、Nrf2和ARE蛋白表达水平;用免疫组织化学法检测脑组织衰老相关β-半乳糖苷酶(SA-β-Gal)表达情况。结果对照组、模型组、低、高剂量实验组小鼠脑组织T-AOC活性分别为(4.95±0.38),(0.69±0.71),(2.98±0.17),(3.76±0.21)U·mg-1;SOD活性分别为(84.21±2.62),(49.33±2.15),(60.76±2.42),(71.23±2.51)U·mg-1;GSH-Px活性分别为(45.56±2.84),(16.23±2.92),(25.97±1.31),(34.43±2.11)U·mg-1;MDA含量分别为(3.54±1.02),(9.21±2.83),(6.13±2.60),(4.86±1.25)nmol·mg-1;脑组织JNK蛋白相对表达量分别为0.95±0.05,0.23±0.06,0.41±0.11,0.68±0.12;Nrf2蛋白相对表达量分别为0.92±0.07,0.09±0.05,0.32±0.07,0.70±0.11;ARE蛋白相对表达量分别为0.90±0.06,0.13±0.07,0.30±0.08,0.62±0.09。低、高剂量实验组分别与模型组比较,差异均有统计学意义(均P<0.05)。结论ASP可通过抑制氧化应激损伤,同时下调SA-β-Gal表达,发挥抗衰老作用,其作用机制可能与激活JNK/Nrf2/ARE抗氧化信号通路的信号转导有关。

Objective To explore the effect of Angelica polysaccharide(ASP)on D-galactose-induced aging model mice by regulating cJun N-terminal kinase(JNK)/transcription factor NF-E2 related factor 2(Nrf2)/antioxidant response element(ARE)signaling pathway.Methods The aging model of mice was established by subcutaneous injection of D-galactose 125 mg·kg^(-1)once daily for 6 weeks.A total of 120 ICR mice were randomly assigned to control group(n=30),model group(n=30),exp-L group(n=30)and exp-H group(n=30).After successful modeling,mice in exp-L group and exp-H group were intraperitoneally injected with 100 mg kg^(-1)ASP and 200mg·kg^(-1)ASP once daily,respectively,while mice in control group and model group were injected with the same amount of normal saline for 4 weeks.The activities of total antioxidant capacity(T-AOC),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and malondialdehyde(MDA)content in brain tissue were detected by ELISA;the expression levels of JNK,Nrf2 and are protein in brain tissue were detected by Western blot;the expression of aging relatedβ-galactosidase(SA-β-Gal)in brain tissue was detected by immunohistochemistry.Results In the control group,model group,exp-L group and exp-H group,the activities of T-AOC were(4.95±0.38),(0.69±0.71),(2.98±0.17),(3.76±0.21)U·mg-1;the activities of SOD were(84.21±2.62),(49.33±2.15),(60.76±2.42),(71.23±2.51)Umg-1;the activities of GSH-Px were(45.56±2.84),(16.23±2.92),(25.97±1.31),(34.43±2.11)U·mg-1;the level of MDA were(3.54±1.02),(9.21±2.83),(6.13±2.60),(4.86±1.25)nmol·mg-1;the relative expressions of JNKprotein were 0.95±0.05,0.23±0.06,0.41±0.11,0.68±0.12;the relative expressions of Nrf2 protein were0.92±0.07,0.09±0.05,0.32±0.07,0.70±0.11;the relative expressions of are protein were 0.90±0.06,0.13±0.07,0.30±0.08,0.62±0.09.There were statistically significant differences between the exp-L/-Hgroup and the model group(P<0.05).Conclusion ASP can inhibit oxidative stress injury,down regulate the expression of SA-β-Gal,and play an anti-aging role.Its mechanism may be related to the activation of JNK/Nrf2/signal transduction pathway.