骨关节炎大鼠关节软骨中YKL-40与Ⅲ型胶原的相关性

摘要

目的 分析骨关节炎(OA)大鼠关节软骨中YKL-40与Ⅲ型胶原的相关性,探讨YKL-40在OA发病过程中的意义.方法 56只健康SD大鼠随机分为7组,每组8只.随机选取一侧膝关节为手术侧,行前交叉韧带离断,建立OA模型.分别于手术当天,手术后2、4、8、12、16、20周随机处死1组大鼠,收集不同时间段手术侧关节软骨标本,行HE染色和番红O/固绿染色,并根据改良Mankin评分对OA标本进行病理分期.免疫组化染色检测YKL-40、Ⅲ型胶原在各期OA关节软骨中的表达,根据平均光密度分析各指标的表达情况,分析YKL-40与Ⅲ型胶原在OA发病过程中的相关性.结果 随着OA病情加重,YKL-40、Ⅲ型胶原表达均逐渐增多,在OA早、中、晚期间差异有统计学意义(P<0.05).YKL-40与Ⅲ型胶原表达呈正相关(rs=0.630,P＜0.05).结论 随着OA病情加重,关节软骨细胞去分化增多.YKL-40高表达与软骨细胞去分化呈正相关,可能是关节软骨对局部退变过程的一种保护性反应.%Objective To investigate the correlation between YKL -40 and type III collagen in knee cartilage of SD rats with osteoarthritis ( OA). Methods Fifty - six SD rats, of which each one random knee was selected for anterior cruciate ligment transaction , were randomly divided into 7 groups ( n = 8). At the end of surgery , the 2nd, 4th, 8th, 12th, 16th and 20th weekend , each random group was sacrificed for collection of femoral condyle cartilages of the operated knees. HE staining and safranin O/fast green staining were applied for pathological observation . Meanwhile , the improved Mankin score was assessed for pathological grading . The expression of YKL - 40 and type Ⅲ collagen in the cartilage were demonstrated by immunohistochemistry method , and were quantified by average optical density . The correlation between YKL - 40 and type Ⅲ collagen was analyzed. Results The expression of YKL - 40 and type Ⅲ collagen increased gradu -ally, as the aggravation of OA with significant differences among phases ( P < 0. 05 ). Meanwhile, the expression of YKL - 40 was significantly positively correlated with type Ⅲ collagen ( r, =0. 630, P < 0. 05). Conclusion Chondrocyte dedifferentiation increases with the aggravation of OA . The up - regulation of YKL - 40 is positively correlated with chon -drocyte dedifferentiation , which may provide protective effects.