Xanthine oxidoreductase polymorphisms: influence in blood pressure and oxidative stress levels

OBJECTIVESOxidative stress can modulate blood pressure levels in different models. Xanthine oxidoreductase is one of the enzymes producing free radicals in the cardiovascular system, and it can contribute to the increment of the oxidative stress and, consequently, blood pressure. We analyzed the association between the −337GA and 565+64CT polymorphisms of the xanthine oxidoreductase gene with blood pressure and oxidative stress levels. METHODSThese polymorphisms were studied in a case–control study (185 patients with hypertension and 385 normotensive controls), we found that these polymorphisms were related to blood pressure levels. This association was high in patients with hypertension and showed an additive effect but did not increase the risk of developing hypertension. We studied an additional and independent sample of patients with hypertension (n=100) to know the association of these polymorphisms with oxidative stress levels. RESULTSWe found that these polymorphisms were related to blood pressure levels. This association was high in hypertensive patients and showed an additive effect, but does not increase the risk of developing hypertension. We have found that the same alleles related with higher blood pressure−337A and 565+64C were related with increased oxidative stress in patients with hypertension. CONCLUSIONSOur results suggest that polymorphisms −337GA and 565+64CT of xanthine oxidoreductase gene are related with blood pressure and oxidative stress in hypertension, adding evidence to the role of xanthine oxidoreductase and oxidative stress in blood pressure.