耐力运动对关节炎大鼠氧化应激与软骨炎性表达及CHRNA7信号的影响

Effects of oxidative stress,chondroinflammatory expression and CHRNA7 signal in endurance exercise arthritis rats

目的探讨耐力运动对关节炎大鼠氧化应激、软骨炎性表达及CHRNA7信号表达的影响。方法将50只SD大鼠随机分为健康组、关节炎组、低耐力组、中耐力组、高耐力组,每组10只。检测各组大鼠行为学及氧化应激水平差异性;采用热板致痛阈值(PWTL)及机械性撤足阈值(PWT);酶联免疫法检测各组大鼠炎性因子水平;采用Western Blot法检测滑膜组织中a7nAChR、STAT3表达情况;HE染色观察大鼠膝关节软骨组织的形态。结果HE染色结果显示,健康组大鼠膝关节软骨表面平整光滑,无裂缝或缺损;关节炎组大鼠膝关节软骨的表面不平整,有缺损;低耐力组大鼠膝关节软骨的表面比较光滑、平整;中、高耐力组大鼠膝关节软骨的表面平整,软骨细胞排列较为整齐。与健康组相比,关节炎组TNF-α、IL-1水平升高(P<0.05);与关节炎组相比,低耐力组、中耐力组和高耐力组TNF-α、IL-1水平降低明显(P<0.05);与低耐力相比,中耐力组TNF-α、IL-1降低明显(P<0.05);与中耐力组相比,高耐力组TNF-α、IL-1水平升高(P<0.05)。与健康组相比,关节炎组大鼠PWTL、PWT、SOD、GSH-Px、α7nAChR、STAT3表达水平明显降低,MDA水平升高(P<0.05);与关节炎组大鼠相比,低、中和高耐力组大鼠PWTL、PWT、SOD、GSH-Px、α7nAChR、STAT3水平升高,MDA水平降低(P<0.05);与低耐力组相比,中耐力组PWTL、PWT、SOD、GSH-Px、α7nAChR、STAT3水平升高,MDA水平降低(P<0.05);与中耐力组相比,高耐力组PWTL、PWT、SOD、GSH-Px、α7nAChR、STAT3水平下降,MDA水平升高(P<0.05)。结论中强度耐力运动可抑制TNF-α、IL-1炎性水平,改善疼痛水平及氧化应激反应,对关节起到保护作用,其机制可能与调控α7nAChR/STAT3蛋白表达有关。

Objective To investigate the effects of endurance exercise on oxidative stress,chondroinflammatory expression and expression of CHRNA7 signal in rats with arthritis.Methods Fifty SD rats were randomly divided into healthy group,arthritis group,low endurance group,medium endurance group and high endurance group,with 10 rats in each group.The levels of behavioral and oxidative stress were detected.Hot plate pain threshold(PWTL)and mechanical withdrawal threshold(PWT)were used.The levels of inflammatory factors were detected by enzyme-linked immunosorbent assay.Western blot was used to detect the expression of a7nAChR and STAT3 in synovial tissues.HE staining was used to observe the morphology of knee cartilage in rats.Results The results of HE staining showed that the cartilage surface of the knee joints in the healthy group was smooth,without cracks or defects.The surface of the knee cartilage of rats in the arthritis group is uneven and defective,while the surface of the knee cartilage of rats in the low endurance group is relatively smooth and flat.The surface of the knee cartilage in the middle and high-dose groups was smooth,and the chondrocytes were arranged more neatly.Compared with the healthy group,the levels of TNF-αand IL-1 in the arthritis group were increased(P<0.05).Compared with the arthritis group,the levels of TNF-αand IL-1 in the low endurance group,the middle endurance group and the high endurance group were increased.The level decreased significantly(P<0.05),Compared with the low endurance group,TNF-αand IL-1 levels in the middle endurance group were significantly reduced(P<0.05).Compared with the middle endurance group,the levels of TNF-αand IL-1 in the high endurance group increased(P<0.05).Compared with the healthy group,the expression levels of hot plate pain-sensitive PWTL,mechanical withdrawal threshold PWT,SOD,GSH-Px,α7nAChR,and STAT3 in the arthritis group significantly decreased,and the MDA level increased(P<0.05).Compared with rats in the arthritis group,the levels of PWTL,PWT,SOD,GSH-Px,α7nAChR,and STAT3 in the low,medium and high endurance groups increased,and the MDA level decreased(P<0.05),Compared with the low endurance group,the PWTL value,PWT,SOD,GSH-Px,α7nAChR,and STAT3 levels in the middle endurance group increased,and the MDA level decreased(P<0.05),Compared with the middle endurance group,the high endurance group PWTL,PWT,SOD,GSH-Px,α7nAChR,STAT3 levels decreased,and MDA levels increased(P<0.05).Conclusion Moderate endurance exercise can inhibit inflammatory levels of TNF-αand IL-1,improve pain levels and oxidative stress,and protect joints.The mechanism may be related to the regulation ofα7nAChR/STAT3 protein expression.