Caffeine and catechin towards prevention of drug induced oxidation of hemoglobin: A spectroscopic study.

Abstract

Administration of low doses of nitrates over prolonged periods in patients suffering from coronary heart disease may lead to chronic methemoglobinemia, a disease caused by oxidation of hemoglobin. Previous reports have shown that natural products like curcumin, vitamin E, vitamin C, resveratrol, etc., are capable of inhibition of nitrite induced oxidation of hemoglobin. Hence in this study we aimed to investigate the preventive role of antioxidants present in our diet, like caffeine and catechin hydrate which are commonly found in coffee and tea towards methemoglobin (met-Hb) formation. Our study revealed that when the hemolysate was pre-incubated with equimolar concentration of caffeine and its metabolite with respect to nitrite, the rate of the nitrite induced oxidation of HbA decreased from (7.33±0.54)×10-5min-1 to (7.09±1.05)×10-5min-1 and (2.98±0.06)×10-5min-1 respectively. Hence it was evident that the metabolite of caffeine, 1-methyluric acid, exhibited better efficiency at physiological concentration than its precursor. On the contrary, only 4mM catechin hydrate could enhance the rate of methemoglobin formation even in absence of nitrite and the rate of the reaction was (6.088±0.31)×10-5min-1 which is comparable with that of 400μM nitrite.