基于核磁共振T2 mapping定量评价温针灸对早期兔膝关节骨关节炎软骨损伤的修复作用

Quantitative evaluation of warm acupuncture-moxibustion in improvement of cartilage damage in rabbits with early knee osteoarthritis based on MR T2 mapping

目的:探讨核磁共振(MR) T2 mapping成像定量评价温针灸对早期膝关节骨关节炎(KOA)家兔软骨退变修复作用的应用价值及T2值与软骨细胞中基质金属蛋白酶(MMP)-1、MMP-13表达的相关性。方法:新西兰家兔随机分为空白组、模型组、温针灸组,每组10只。采用右后肢伸直位石膏管型固定法制备早期KOA模型。温针灸组选取右后肢“鹤顶”“内膝眼”“外膝眼”“足三里”给予温针灸治疗15 min,1次/d,连续治疗2周。干预结束后对各组家兔行膝关节MR T2 mapping成像;HE染色及Mankin评分评价各组家兔膝关节软骨病理形态学改变;TUNEL法观察各组家兔膝关节软骨细胞凋亡情况;免疫组织化学法检测各组家兔膝关节软骨中MMP-1、MMP-13的表达;分析各组家兔膝关节软骨T2值与MMP-1、MMP-13表达的相关性。结果:与空白组比较,模型组软骨细胞排列紊乱,软骨层变薄,Mankin评分、软骨细胞凋亡指数、T2值及软骨组织中MMP-1、MMP-13蛋白表达均升高(P<0.01);与模型组比较,温针灸组软骨细胞排列整齐,结构清晰,Mankin评分、软骨细胞凋亡指数、T2值及软骨组织中MMP-1、MMP-13蛋白表达均降低(P<0.01)。T2值与MMP-1、MMP-13的表达水平均呈正相关(P<0.01)。结论:温针灸可降低早期KOA兔关节软骨中T2值,与降低软骨细胞外基质中MMP-1、MMP-13蛋白表达呈正相关,T2值对评估温针灸修复KOA兔早期软骨退变有一定的应用价值。

Objective To observe the application value of MR T2 mapping for evaluating the effect of warm acupuncture-moxibustion on articular cartilage degeneration,and to observe the relationship between T2 value and ex⁃pression of matrix metalloproteinases(MMP)-1 and MMP-13 of chondrocytes in rabbits with early knee osteoarthritis(KOA).Methods Thirty male New Zealand rabbits were randomly divided into blank control,KOA model and warm acupuncture-moxibustion groups,with 10 rabbits in each group.The early KOA model was established by right hind limb tubular plaster extension fixation method for 2 weeks.The rabbits of the warm acupuncture-moxibustion group re⁃ceived warm acupuncture-moxibustion stimulation at“Heding”(EX-LE2),“Neixiyan”(EX-LE4),“Waixiyan”(EX-LE5)and“Zusanli”(ST36)on the right hind limb for 15 min,once a day for 2 weeks.After intervention,MR T2 mapping of the right knee joint was performed in each group.The H.E.staining was used to evaluate the histopathological changes of cartilage,followed by giving a score according to the standards of Mankin scoring.The TUNEL method was used to analyze the apoptosis state of chondrocytes,and the positive expressions of MMP-1 and MMP-13 in the articular carti⁃lage were detected by immunohistochemical staining.Results Compared with the blank control group,the Mankin score,chondrocyte apoptosis index,T2 value and the positive expressions of MMP-1 and MMP-13 in the cartilage tissue were significantly increased in the model group(P<0.01).Compared with the model group,the Mankin score,chondrocyte apoptosis index,T2 value and the positive expressions of MMP-1 and MMP-13 in the cartilage tissue were markedly decreased in the warm acupuncture-moxibustion group(P<0.01).The T2 value was positively correlated with the expression levels of MMP-1 and MMP-13(P<0.01).H.E.staining showed disordered arrangement of chondrocytes and thinner cartilage layer in the model group,and a clear and relative ordered arrangement of chondrocyte in the warm acupuncture-moxibustion group.Conclusion Warm acupuncture-moxibustion can reduce the T2 value of articular car⁃tilage in early KOA rabbits,which is positively correlated with the decreased expression of MMP-1 and MMP-13 in the extracellular matrix of cartilage.The MR T2 mapping has certain value in evaluating the effect of warm acupuncturemoxibustion on KOA rabbits with early cartilage degeneration.