Roles Of The Expression Of Caspase-1 And Chondropotosis In Pathogenesis Of Human Osteoarthritis And Correlative Study

Objective To observe the expression of Caspase-1 and apoptotic percentage of chondrocyte in human osteoarthritic articular cartilage. To explore the possible involvement of Caspase-1 and chondropotosis in the pathogenesis and progression of human osteoarthritis (OA) respectively, and make a pilot study on the correlation between the expression of Caspase-1 and chondrocyte apoptotic percentage as to give a theoretical evidence for diagnosis and treatment of OA.Methods Thirty-six femoral heads and tibial plateaus were obtained after total hip arthroplasty or amputation, which divided into four groups namely control group, mild OA group, moderate OA group and severe OA group according to a modified Mankin scoring system, through HE staining and Safranin O staining. Meanwhile, the expression of Caspase-1 and apoptotic cell percentage of articular cartilage were investigated by immulohistochemical analysis and TUNEL method. All data were analyzed by SPSS 15.0 statistical software. The mean gray of Caspase-1 and apoptotic cell percentage of each group were analyzed by t-test and one-way ANOVA; the correlation between the mean gray, apopotic percentage and Mankin pathological score respectively, and the correlation between the mean gray and apoptotic percentage were evaluated by Pearson correlative analysis, the statistic significance was set atα=0.05.Results (1) The mean gray of the control group and OA group were 188.022±16.429 and 143.247±29.848, respectively, there was a significant difference (p<0.01); among which, the mean gray of mild, moderate and severe OA group were 164.570±11.553, 156.507±18.263 and 111.546±23.880, respectively, all the inter-group difference were significant except between mild group and moderate group (p>0.05); furthermore, the mean gray of Caspase-1 was negative correlative with Mankin pathological score (r=-0.761, p<0.05), in other word, the expression of Caspase-1 was positive correlative with Mankin score instead. (2) The mean apoptotic cell percentage of the control group and OA group were 0.026±0.025 and 0.311±0.173, respectively, there was a significant difference (p < 0.01); among which, the mean apoptotic percentage of mild, moderate and severe OA group were 0.153±0.056, 0.296±0.124 and 0.514±0.061, respectively, all the inter-group difference were significant (p<0.05); furthermore, the apoptotic percentage was positive correlative with Mankin pathological score (r-0.935, p<0.05). (3) There are no significant correlation between the mean gray of Caspase-1 and apoptotic cell percentage (p>0.05).Conclusions (1) Caspase-1 take a certain role in the pathogenesis and progression of OA, which could reflect the severity of the OA. (2)Chondroptosis is a possible pathogenesis in OA, and apoptotic percentage could impact the progression of OA. (3) Caspase-1 does not participate in the apoptotic event directly, the expression of which could not be correlative with the percentage of chondroptosis..