Investigation of Some Vitamin Type Inhibition on Human Cord Blood Carbonic Anhydrase I and II

Objective: Human cord blood, a specialized blood tissue, contains many substances including several enzymes which act by different biochemical reactions. Carbonic anhydrase (CA) isoenzymes are one of the most important enzyme family which are crucial for living organisms to survive. However, there is limited data regarding the effect of vitamins on CA isoenzymes. The aim of this study is to test the inhibitory effect of some widely used vitamins on human cord blood CA I and II (hcbCA I and hcbCA II). Methods: We purified hcbCA I and hcbCA II from human cord blood erythrocytes by Sepharose-4B-l-tyrosine-sulfanilamide affinity gel chromatography. The inhibitory effects of vitamin A (retinol), vitamin B12 (cyanocobalamin) and vitamin K (menadione sodium bisulfate, k3) on two isoenzyme were checked using IC50 values. Result: IC 50 values for vitamin A, vitamin B12 and vitamin K were found to be 44, 90, and 31 μM for hcbCA I and of 51, 62, and 21 μM for hcbCA II; respectively. All these substances were found to be non-competitive inhibitors. Conclusion: Vitamins are vitally important for continuation of life and activity of some of enzymes. While the physicans recommend pregnant women to take vitamins during pregnancy, we suggest that the findings obtained in this study be taken into consideration. (JAREM 2013; 3: 79-83)