Aspirin impairs antioxidant system and causes peroxidation in human erythrocytes and guinea pig myocardial tissue

This study aims to investigate possible effects of aspirin treatment on cel lular oxidant/antioxidant system. In the first part of the study, 15 guinea pigs were given aspirin at three different doses (2200, 440 and 10 mg/kg/d ay) for 30 days and five were fed on the same diet without aspirin. After a month, animals were killed and their hearts were removed for use in analys es. In the other part, after fasting blood samples were obtained from 11 vo lunteer subjects, they were given aspirin (approximately 10 mg/kg/day) for 30 days and second blood samples were obtained after 1 month. Five voluntee r subjects also participated as placebo control. Oxidant/antioxidant parame ters, namely superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), c atalase (CAT), malondialdehyde (MDA), nonenzymatic superoxide scavenger act ivity (NSSA), susceptibility to oxidation (SO) and antioxidant potential (A OP) values, were assayed in the samples. Antioxidant system was found to be impaired in the heart tissue from guinea pigs and in the erythrocytes from volunteer subjects. AOP and NSSA values were lower and MDA higher after as pirin treatment in both heart tissues and erythrocytes. In guinea pig heart tissue, SO was lower, but GSH-Px and CAT were unchanged after aspirin trea tment. In human erythrocytes, SO was unchanged, but GSH-Px and CAT activiti es were increased after aspirin treatment. Changes in guinea pig heart tiss ues from animals treated with higher aspirin doses were more drastic relati ve to those of human erythrocytes, but no meaningful differences were obser ved between analysis parameters of control and lower-dose (10 mg/kg/day) as pirin-treated animals. Our results suggest that high-dose aspirin exerts si gnificant toxicity to guinea pig myocardium and normal dose aspirin may cau se peroxidation in the human erythrocytes due to its oxidant potential. We suppose that antioxidant supplementation may be beneficial for the people u sing aspirin for longer periods in order to prevent peroxidation damages.