The investigation of the relationship between the carbonic anhydrase I and II autoantibodies and the oxidative stress parameters in the patients with hypothyroidism and hyperthyroidism

Autoimmunity is the immune response of an organism against its own tissue antigens and the disease that results from such an aberrant immune response is termed as an autoimmune disease. The mechanisms of these diseases are not well known and, determinaton of autoantibodies towards their own tissues are used for their diagnosis.Carbonic anhydrase, CA, (E.C.4.2.1.1) is a zinc containing metalloenzyme which is widely distributed among all types of organisms and has the physiological function of hydration of CO2 and dehydration of H2CO3. CA autoantibodies have been shown in many autoimmune based diseases.Oxidative stress is the pathological situation which appears as the result of the reactions of the reactive oxygen species with biomolecules. The correlation between oxidative stress and autoimmune diseases is very important.In this study, it was aimed to determine the presence of any correlation between anti-CA I and anti-CA II levels and oxidative stress markers after determining their levels in thyroid diseases and also to see if these parameters could be used for diagnosis of this disease.Total 108 patients of which 39 with hypothyroid and 69 with hyperthyroid were included to this study. Our control group consisted 52 healthy persons. In the sera of these groups the levels of anti-CA I, anti-CA II, total antioxidant, total oxidant status (TAS, TOS) oxidative stress index (OSI), protein carbonyl group and for erythrocyte hemolysates superoxide dismutase and catalase were measured.The anti-CA I, anti-CA II, TOS, OSI, SOD levels of the both groups with hypothyrid and hyperthyroid were found to be higher than the control group. The difference between these groups were statistically significant (p<0.001). In addition, for both hypothyrid and hyperthyroid groups an important positive corelation between anti-CA I and CA II values (p=0.0001) were found. In the hypotyroid group a negative correlation between protein carbonyl group levels and anti-CA I and anti-CA II values were seen.In conclusion, in early diagnosis of thyroid diseases, anti-CA I and anti-CA II values could be used as a marker, whereas, oxidative stress parameters could not be used for this purpose.