Association of plasma and heart homocysteine and blood malondialdehyde with cardiovascular diseases induced by acute selenium deficiency in lambs

The association between heart and plasma homocysteine, malondialdehyde status and whole blood and plasma selenium concentration were studied in lambs affected with the cardiac (n = 17) and the skeletal muscle (n = 28) form of nutritional muscular dystrophy and the results were compared with those in healthy lambs (n = 50). In the selenium-deficient lambs, the levels of plasma and heart tissue homocysteine were higher (P < 0.001) in the cardiac form and lower (P < 0.001) in the skeletal form of the disease. In comparison with results in the healthy lambs, the activity of creatine kinase, aldolase and catalase, and the concentrations of erythrocytes malondialdehyde were higher (P < 0.001) in the affected lambs. Heart tissue homocysteine concentration of the selenium-deficient lambs was correlated positively (P < 0.01) with erythrocyte glutathione peroxidase activity and blood selenium concentration. In addition, there was an inverse relationship between plasma homocysteine and whole blood selenium concentration in the lambs with the cardiac form of the disease (P < 0.01), conversely; a direct relationship was observed between these variables in the skeletal muscle form of the disease (P < 0.01). The results would suggest that in selenium-deficient lambs the increased concentration of homocysteine may have a role in myocardial damage by exacerbating the damaging effects of oxidative agents on heart tissue.