摘要
目的:从沉默信息调节因子1(SIRT1)/腺苷酸活化蛋白激酶(AMPK)信号通路介导自噬角度,探讨白藜芦醇对大鼠膝关节骨性关节炎(KOA)软骨细胞凋亡的影响.方法:50只健康Wistar大鼠随机分为对照组、模型组、白藜芦醇组、白藜芦醇+SIRT1抑制剂组、自噬激活剂组,每组10只.除对照组外其余大鼠均通过注射弗氏完全佐剂造模法复制KOA大鼠模型,白藜芦醇组、白藜芦醇+AMPK抑制剂组、自噬激活剂组分别使用10 µmol/kg白藜芦醇、10 µmol/kg白藜芦醇+10 mg/kg EX527、2 mg/kg雷帕霉素进行干预,4周后,观察大鼠Lequesne MG膝关节级别;测定大鼠膝关节液中IL-6、肿瘤坏死因子β(TNF-β)水平;HE染色与TUNEL染色观测大鼠膝关节软骨组织形态及凋亡情况;透射电子显微镜观察大鼠软骨细胞自噬情况;Western blot法检测SIRT1、p-AMPK、AMPK、LC3、Beclin-1蛋白表达.结果:与对照组相比,模型组局部反应、步态反应、关节活动、关节肿胀程度加重(P<0.05);与模型组相比,白藜芦醇组、自噬激活剂组局部反应、步态反应、关节活动、关节肿胀程度减轻(P<0.05).与对照组相比,模型组大鼠软骨组织细胞排列紊乱,粗糙,存在纤维化变性、边缘丘状隆起,细胞器减少,可见空泡变性,自噬小体数目增多,膝关节液IL-6、TNF-β水平、软骨细胞凋亡率、Beclin-1和LC3B/A升高(P<0.05),软骨组织SIRT1、p-AMPK/AMPK降低(P<0.05);与模型组相比,白藜芦醇组、自噬激活剂组大鼠软骨组织细胞排列紊乱、边缘丘状隆起等现象有改善,自噬小体数目增多,膝关节液IL-6、TNF-β水平、软骨细胞凋亡率降低(P<0.05),软骨组织SIRT1、p-AMPK/AMPK、Beclin-1和LC3B/A水平升高(P<0.05);SIRT1抑制剂可逆转白藜芦醇组对大鼠软骨细胞的保护作用.结论:白藜芦醇可能是通过激活SIRT1/AMPK通路介导自噬KOA大鼠软骨细胞凋亡,SIRT1抑制剂可逆转此过程.
Abstract
Objective:To investigate the effect of resveratrol on apoptosis of chondrocytes in rats with knee osteoarthritis(KOA)through autophagy mediated by silent information regulator 1(SIRT1)/adenylate activated protein kinase(AMPK)signaling pathway.Methods:Fifty healthy Wistar rats were randomly separated into control group,model group,resveratrol group,resveratrol+ SIRT1 inhibitor group,and autophagy activator group,with 10 rats per group.Except for the control group,the other rats were injected with Freund's complete adjuvant to establish the KOA rat model,resveratrol group,resveratrol+AMPK inhibitor group,and autophagy activator group were treated with 10 µmol/kg resveratrol,10 µmol/kg resveratrol+10 mg/kg EX527,2 mg/kg rapamycin,respectively.After 4 weeks,the grade of Lequesne MG knee joint of rats were observed;the levels of IL-6 and tumor necrosis factor-β(TNF-β)in rat knee joint fluid were measured;HE staining and TUNEL staining were used to observe the morphology and apoptosis of rat knee cartilage;transmission electron microscope was used to observe the autophagy in rat chondrocytes;Western blot was performed to determine the protein expressions of SIRT1,p-AMPK,AMPK,LC3 and Beclin-1.Results:Compared with control group,the local reaction,gait reaction,joint activity,and joint swelling of model group were increased;compared with model group,the local response,gait response(P<0.05),joint activity,and joint swelling in resveratrol group and autophagy activator group were reduced(P<0.05).Compared with control group,the cartilage tissue cells in model group were disordered and rough,with fibrotic degeneration,marginal humeral bulge,reduced organelles,and vacuolar degeneration,the number of autophagosomes was increased,the levels of IL-6 and TNF-β in knee joint fluid,chondrocyte apoptosis rate,Beclin-1 and LC3B/A were increased(P<0.05),the SIRT1 and p-AMPK/AMPK in cartilage tissue were decreased(P<0.05);compared with model group,resveratrol group and autophagy activator group showed improvement in the disordered arrangement of cartilage tissue cells and the marginal humeral bulge,the number of autophago-somes was increased,the levels of IL-6 and TNF-β in knee joint fluid,and the apoptosis rate of chondrocytes were decreased(P<0.05),the levels of SIRT1,p-AMPK/AMPK,Beclin-1 and LC3B/A in cartilage tissue were increased(P<0.05);SIRT1 inhibitor could reverse the protective effect of resveratrol group on rat chondrocytes.Conclusion:Resveratrol maybe autophagic KOA rat chon-drocyte apoptosis mediated by activating SIRT1/AMPK pathway,which can be reversed by SIRT1 inhibitor.
基金项目
武汉市卫生健康委中医药科研项目(2021)(WZ20Z01)