Experimental Study On The Correlation Between Creatine Kinase (CK) System And Knee Osteoarthritis

Objective.The etiology of OA disease is complex and unclear,and many factors are related to it.In recent years,studies have confirmed that Mitochondrial dysfunction caused by increased reactive oxygen species(ROS)of oxidative stress plays a critical role in the pathogenesis of osteoarthritis(OA).The classical related mitochondrial antioxidant enzyme SOD has been used as a serum evaluation factor and serum marker in OA,and has become an obvious quantitative index to reduce oxidative stress in the clinical treatment of OA disease.Creatine kinase system,which also has potential antioxidant activity,however,have not yet been investigated in OA,although they have been repeatedly mentioned in the study of heart disease.The purpose of our study was to evaluate the changes of CK and its isozyme activity in knee osteoarthritis(KOA)patients,assess their relationship to OA's radiographic grades.To understand the correlation between creatine kinase system and antioxidant enzyme SOD in KOA patients,and to explor whether CK system is related to OA disease and oxidative stress mechanism.Methods.A retrospective study of 100 healthy controls,103 knee OA patients was performed.All individuals' serum levels of CK-MB and CK were measured using the immunosuppressant rate method.The CK-MM,CK-MB to CK ratio,CK-MM to CK was then calculated.The Student t-test was used to compare mitochondrial related enzyme(CK-MB,CK-MM,CK,CK-MB/CK and CK-MM/CK)levels in OA patients with those of healthy controls,and the serum characteristics of KOA patients were analyzed.Serum SOD was determined by colorimetric method,and oxidative stress KOA population was modeled by changes of SOD activity.Then Pearson correlation test was used to investigate the correlation between CK system and SOD activity in knee OA patients,and the relationship between CK family and SOD index.The application value of each parameter in KOA severity grade was discussed by exploring the change trend of the mean value of each parameter in KOA group.Results.The results of this study show that significantly decreased CK-MM,CK and CK-MM/CK levels were observed in the OA patients [CK-MM:(t=2.869,P=0.004)P<0.05,CK:(t=2.596,P=0.010)P<0.05,CK-MM/CK:(t=5.900,P= 0.000)P<0.001respectively] on comparison with the healthy controls.Significantly increased CK-MB and CK-MB/CK levels were observed in the OA patients [CK-MB:(t=3.602,P=0.000)P<0.001,CK-MB/CK:(t=5.900,P=0.000)P<0.001 respectively] on comparison with the healthy controls.CK-MM,CK and CK-MM/CK levels also decreased in patients with a higher grade of OA progression [CK-MM:(t=3.569,P= 0.001)P<0.05,CK:(t=2.985,P=0.004)P<0.05,CK-MM/CK:(t=4.885,P=0.000)P<0.001,respectively].CK-MB/CK was shown to have a increasing trend(t=4.885,P= 0.000)P<0.001.CK-MB was not statistically significant.Compared with the control group,SOD activity was decreased in KOA patients:(t=8.176,P= 0.000)P<0.001.SOD levels also decreased in patients with a higher grade of OA progression:(t=5.771,P=0.000)P<0.001.In KOA patients,SOD was positively correlated with CK-MM,CK,CK-MM/CK.There was a negative correlation with CK-MB/CK,but no significant correlation with CK-MB.In KOA group,CK-MM,CK,CK-MM/CK and SOD had the same trend at KOA K-L(1-4)level,and CK-MM/CK and SOD had the closest trend.The severity of KOA could be effectively evaluated by using the above indicators.Conclusion.The study confirms that the creatine kinase system,which has long been considered a specific serological marker of the heart,is associated with KOA.The creatine kinase system is involved in the pathogenesis and development of KOA disease,and the creatine kinase system related indicators have decreased activity in KOA patients.The higher the severity of KOA,the more significant the activity decrease was.The reason may be that the oxidative mechanism of OA may cause damage to the creatine kinase system,resulting in its reduced activity.The correlation of the creatine kinase system with SOD in the serum of OA patients confirmed our hypothesis that the creatine kinase system may have an antioxidant activity similar to SOD,which is similar to the trend of SOD in KOA patients.Some neglected interdisciplinary serum indexes may play an important role in the pathogenesis of OA.In the future,creatine kinase system is expected to become another KOA serum evaluation index and serum marker after SOD.