EVALUATION OF CYTOSOLIC ERYTHROCYTE CARBONIC ANHYDRASE IN FLUOROSIS

The present study examined cellular membrane aspects of fluoride exposure at high concentrations in human populations suffering from fluorosis. 500 patients of fluorosis and 120 controls were randomly selected from endemic high fluoride areas of Bathinda district, Punjab, India. The mean activity of carbonic anhydrase exhibited significant reduction (F = 4589.693, P<0.0001) in fluorotic patients than control. Pearson’s bivariate correlation and simple linear regression analysis showed significant negative relationships of increasing concentration of water fluoride (r = -0.992, R2 = 0.983, Y = 0.05-0.002 X, P<0.001) and serum fluoride (r = -0.98, R2 = 0.960, Y = 0.05-0.5 X, P<0.05) with activity of carbonic anhydrase. The concentration of bicarbonate ion was significantly (F = 2931.298, P<0.0001) lower in patients of all study groups in comparison to control. Pearson’s bivariate correlation and quadratic regression analysis revealed significant (P<0.05) negative association of water fluoride (r = -0.915, R2 = 0.961, Y = 16.22+0.09 X-0.02 X2) with bicarbonate ion concentration. The concentration of chloride ion showed significant (F = 11093.939, P<0.0001) decrease in fluorotic patients as compared to control. Pearson’s bivariate correlation and simple linear regression analysis demonstrated significant (P<0.05) negative relationship between water fluoride and chloride ions (r = -0.987, R2 = 0.973, Y = 5.19-0.09 X) as well as with serum fluoride (r = -0.972, R2 = 0.945, Y = 5.23-2.92 X). These results suggest disruption of carbonic anhydrase activity with subsequent depression of ionic homeostasis associated with fluoride toxicity, provide an intracellular mechanisms of interaction and important health implications for the widespread occurrence of fluorosis among people living in endemic fluoride areas.