Homocysteine Thiolactone Induces Cardiac Dysfunction: Role of Oxidative Stress

This study investigates the cardiac functioning in male Wistar rats after treatments with methionine and homocysteine thiolactone (HcyT). the rats were distributed into 3 groups and treated for 8 weeks. Group I was the control (CO) group, given water, group II was treated with methionine, and group III with HcyT (100 mg/kg). Morphometric and functional cardiac parameters were evaluated by echocardiography. Superoxide dismutase (SOD), catalase, and glutathione S-transferase activities, chemiluminescence, thiobarbituric acid reactive substances, and immunocontent were measured in the myocardium. Hyperhomocysteinemia was observed in rats submitted to the both treatments. the results showed diastolic function was compromised in HcyT group, seen by the increase of E/A (peak velocity of early (E) and late (A) diastolic filling) ratio, decrease in deceleration time of E wave and left ventricular isovolumic relaxation time. Myocardial performance index was increased in HcyT group and was found associated with increased SOD immunocontent. HcyT group demonstrated an increase in SOD, catalase, and glutatione S-transferase activity, and chemiluminescence and thiobarbituric acid reactive substances. Overall, these results indicated that HcyT induces a cardiac dysfunction and could be associated with oxidative stress increase in the myocardium.Univ São Paulo, Inst Coracao, Dept Hipertensao Expt, Unidade Hipertensao, BR-09500900 São Paulo, BrazilUniv Fed Rio Grande do Sul, Dept Fisiol, Lab Fisiol Cardiovasc, Inst Ciencias Basicas Saude, Porto Alegre, RS, BrazilUniv São Paulo, Inst Coracao, Unidade Clin Miocardiopatia, BR-09500900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biociencias, São Paulo, BrazilUniv Fed Ciencias Saude Porto Alegre, Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Dept Biociencias, São Paulo, BrazilWeb of Scienc