脂肪干细胞对膝骨关节炎疼痛及软骨修复的影响

Effects of adipose-derived stem cells on pain and cartilage renovation in knee osteoarthritis

目的观察脂肪干细胞(ADSCs)对膝骨关节炎(KOA)大鼠关节疼痛和软骨修复的作用。方法从大鼠腹股沟抽取脂肪制备培养ADSCs,以碘乙酸法复制大鼠KOA疼痛模型。将40只SD大鼠随机分为空白组、KOA模型组、ADSCs低浓度治疗组、ADSCs中浓度治疗组、ADSCs高浓度治疗组,每组8只。采用低(1×10^6个/ml)、中(1×10^7个/ml)、高(1×10^8个/ml)3种浓度的ADSCs对大鼠进行双侧关节腔注射干预,每周注射1次,定期观察大鼠的生理行为并评价疼痛指标,注射4次后取大鼠膝关节进行组织病理学观察及Mankin's评分。结果压痛实验结果表明,模型复制后第2和4周时,5组大鼠的压痛阈值比较结果:①不同时间点大鼠压痛阈值有差异(P<0.05);②5组间大鼠压痛阈值无差异(P>0.05);③5组间的压痛阈值变化趋势有差异(P<0.05)。热痛实验结果表明,模型复制后第2和4周时,5组大鼠的热痛阈值比较结果:①不同时间点大鼠热痛阈值有差异(P<0.05);②5组间大鼠热痛阈值无差异(P>0.05);③5组的热痛阈值变化趋势无差异(P>0.05)。病理学结果表明,与空白组比较,KOA模型组大鼠膝关节软骨表面缺损,缺损处软骨细胞丢失,蛋白聚糖降解,软骨下骨呈现纤维化退变;低、中、高浓度ADSCs对大鼠膝关节均有改善作用。其中ADSCs低浓度治疗组仍可见软骨表面缺损、软骨细胞缺失和肥大化表型;ADSCs中浓度治疗组软骨细胞存活,但仍有表面缺损和细胞肥大化退变;ADSCs高浓度治疗组软骨基本恢复正常,软骨面增厚,仅有少量肥大软骨细胞。KOA模型组的Mankin's评分均高于空白组、ADSCs低浓度治疗组、ADSCs中浓度治疗组和ADSCs高浓度治疗组(P<0.05)。结论ADSCs可改善KOA大鼠关节疼痛,并修复软骨损伤。该技术可用于临床KOA的辅助治疗。

Objective To observe the effect of adipose-derived stem cells(ADSCs)on pain and cartilage renovation in knee osteoarthritis(KOA).Methods The ADSCs with different concentration(1×10^6/ml,1×10^7/ml,1×10^8/ml)were obtained from fats in SD rats,and the pain models of KOA in rats were established by iodoacetic acid method.40 SD rats were selected and were randomly divided into blank group,KOA model group,ADSCs low-concentration group,ADSCs middle-concentration group and ADSCs high-concentration group,8 cases in each group.The rats in ADSCs low-concentration group,ADSCs middle-concentration group and ADSCs highconcentration group were administrated with intra-articular injection of low-concentration ADSCs,middleconcentration ADSCs and high concentration ADSCs in bilateral knee joint,once a week for consecutive 4 weeks.Pressure-pain threshold,Paw withdrawal latency(PWL)and Mankin's scoring of knee joint were performed regularly,and pathological results were observed after 4 injections.Results At the 2nd and 4th week after the model replication,the results of the tenderness experiment showed that the comparison results of the tenderness thresholds of the five groups were as follows:there were differences in the tenderness thresholds at different time points(P<0.05);there was no difference in the tenderness thresholds among the five groups(P>0.05);there were differences in the change trend of the tenderness thresholds among the five groups(P<0.05).Meanwhile,the results of the hot pain experiment showed that the hot pain thresholds of the five groups were different at different time points(P<0.05);there was no difference in hot pain thresholds among the five groups(P>0.05);there was no difference in the change trend of the hot pain thresholds among the five groups(P>0.05).Compared with the blank group,the pathological results showed that the KOA model group had the defect of articular cartilage surface,the loss of chondrocytes,proteoglycan degradation,fibrosis and degeneration of subchondral bone;low,medium and high concentration ADSCs had the improvement effect on the articular cartilage.Among them,cartilage surface defect,chondrocyte deletion and hypertrophic phenotype were still found in the low concentration ADSCs treatment group;chondrocytes survived in the middle concentration ADSCs treatment group,but there were still surface defects and cell hypertrophic degeneration;cartilage in the high concentration ADSCs treatment group basically returned to normal,cartilage surface thickened,and only a small number of hypertrophic chondrocytes were found.The Mankin's score of KOA model group was higher than that of blank group,ADSCs low concentration treatment group,ADSCs medium concentration treatment group and ADSCs high concentration treatment group(P<0.05).Conclusion ADSCs can ameliorate joint pain in KOA rats and repair cartilage damage,suggesting this technique can be used for adjuvant treatment of clinical KOA.