摘要
目的检测Notch信号通路在激活和失活状态下,鼠膝骨关节软骨细胞中Notch1、Bax和Bcl-2基因的表达情况,探讨Notch信号通路在大鼠膝骨关节炎(osteoarthritis,OA)软骨细胞凋亡中的作用机制。方法选取34只无特定病原体级Sprague Dawley大鼠,其中32只使用Hulth方法制造右膝OA模型,余下2只正常饲养。4周后,造模大鼠随机选择2只以及正常饲养的2只大鼠全部处死,观察右膝软骨的形态变化,并进行病理检查证实造模成功,余下的30只大鼠随机分成激活组、抑制组、空白对照组,每组10只。于每周星期二、五行大鼠膝关节腔注射,其中激活组注射Nocth信号通路特异性激活剂Jagged1蛋白25 ng/kg,抑制组注射γ分泌酶抑制剂DAPT(GSI-IX)100 ng/kg,空白对照组注射同体积磷酸盐缓冲液。关节腔注射8周后全部处死大鼠,取右膝股骨髁关节骨软骨标本,大体观察3组大鼠膝关节软骨的退变程度,行光学显微镜下组织形态学观察及Mankin评分,并采用免疫组织化学检测各组软骨细胞中Notch1、Bax和Bcl-2蛋白的表达情况。结果关节腔注射8周后,抑制组、空白对照组、激活组Mankin评分分别为(3.40±0.84)、(6.70±0.95)、(11.10±1.37)分,组间两两比较差异均有统计学意义(P<0.05)。抑制组大鼠膝关节软骨的Notch1、Bax阳性率均低于空白对照组及激活组(P<0.05),Bcl-2阳性率高于空白对照组及激活组(P<0.05)。结论 Notch信号通路激活后可能通过凋亡途径上调Bax蛋白,下调Bcl-2蛋白,从而促进软骨细胞凋亡,加重OA;Notch信号通路抑制后可能通过凋亡途径下调Bax蛋白,上调Bcl-2蛋白,从而抑制软骨细胞凋亡,减轻OA发展。
Objective To detect the expression of Notch1, Bax, Bcl-2 genes in rat knee joint cartilage cells in a state of activation and inactivation of the Notch signaling pathway, and preliminarily study the mechanism of Notch signaling pathway on experimental rat knee osteoarthritis(OA) chondrocytes apoptosis. Methods A total of 34 speceficpathogen-free Sprague Dawley rats were selected, of which 32 were established the right knee OA models using Hulth method, and the other 2 were normally fed. Four weeks later, two randomly selected OA rats and the two normally fed rats were put to death, to observe the morphological changes of the right knee and ensure the OA models were successfully established by pathology examination. The remaining 30 rats were randomly divided into three groups with 10 in each.The rats were injected intra-articularly on each Tuesday and Friday, with Nocth signal pathway specific activator Jagged1 protein(25 ng/kg) in the activation group, γ-secretase inhibitor DAPT(GSI-IX)(100 ng/kg) in the inhibition group, and phosphate-buffered saline in the control group, respectively. The rats were sacrificed after 8 weeks of articular cavity injection. Taking the right knee articular cartilage speciments of femoral condyle, we observed the degeneration of articular cartilage of the three groups, observed the histomorphological changes by microscope, evaluated the Mankin scores, and used the immunohistochemistry to detect the expression of Notch1, Bax, Bcl-2 proteins. Results After the 8-week articular cavity injection, the Mankin scores in the activation group, the inhibition group, and the control group were 3.40±0.84, 6.70±0.95, 11.10±1.37, respectively, and the differences between the three groups were statistically significant(P〈0.05). The positive rates of Notch1 and Bax of chondrocyte in the inhibition group were lower than those in the control group and the activation group(P〈0.05), while the positive rate of Bcl-2 of chondrocyte in the inhibition group was higher than t
作者
吴绍军
刘俊才
左银龙
李忠
WU Shaojun;LIU Juncai;ZUO Yinlong;LI Zhong(Department of Bone and Joint Surgery,Affiliated Hospital of Southwest Medical University,Luzhou,Sichuan 646000,P.R.China;Department of Orthopaedics,Chongqing Dazu People's Hospital,Dazu,Chongqing 402360,P.R.China)
出处
《华西医学》
CAS
2018年第9期1162-1167,共6页
West China Medical Journal
基金
四川省教育厅课题(11ZA249)