Lipid peroxidation and antioxidant status in experimental animals: Effects of aging and hypercholesterolemic diet

Effects of aging and hypercholesterolemic diet on lipid peroxidation and antioxidant status were investigated in rats. The rats were divided into four groups of ten: Group I; young rats receiving standard lab chow; Group II; young rats on hypercholesterolemic diet (0.4 g/rat/day); Group III; aged rats receiving standard lab chow; Group IV; aged rats on hypercholesterolemic diet (0.4 g/rat/day). Plasma lipid peroxidation end product level was determined as thiobarbutiric acid reactive substances (TEARS). Plasma cholesterol concentration was analyzed by a kinetic enzymatic method. Erythyocyte superoxide dismutase (CuZn SOD), glutathione peroxidase (GSH Pr) and glutathione (GSH) levels were determined spectrophotometrically. Cholesterol values were found to be significantly high (p p > 0.02) and GSH (p p > 0.02) was observed in aged rats. In young rats hyperchlesterolemic diet caused a significant increase in both GSH and CuZnSOD levels. Our results indicate an imbalance between radical production and destruction in favour of prooxidant conditions in the young rats and the induction by hypercholesterolemic diet of the antioxidative response in erythrocytes. (C) 1997 Elsevier Science B.V

The effect of iron supplementation on GSH levels, GSH-Px, and SOD activities of erythrocytes in L-thyroxine administration

Our aim was to study the effect of iron supplementation on the following aspects of erythrocyte metabolism in experimental hyperthyroidism: glutathione (GSH) levels, glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) activities. Hyperthyroidism induced by L-thyroxine administrations significantly raised erythrocyte GSH, GSH-Px and SOD levels of the rats (P < 0.001). Likewise, we observed that iron supplementation induced significant rises in erythrocyte GSH, GSH-Px and SOD levels (P < 0.001) as compared with the control group. The erythrocyte GSH, GSH-Px and SOD levels of hyperthyroidism-induced iron-supplemented animals were significantly higher when compared with either the iron-supplemented group (P < 0.001) or the only L-thyroxine-administered hyperthyroid group (P < 0.001, P < 0.05, P < 0.01, respectively). The results of this study show that L-thyroxine administration and/or iron supplementation increases GSH, GSH-Px and SOD levels of erythrocytes

Plasma AGE-peptides and C-peptide in early-stage diabetic nephropathy patients on thiamine and pyridoxine therapy

Aim. The aim of the study was to evaluate circulatory AGE-peptide levels in diabetic nephropathy and to observe the effects of thiamine (vitamin B1) and pyridoxine (vitamin B6) therapy

Could L-carnitine be an acute energy inducer in catabolic conditions?

Serum free carnitine levels in five children (aged between 2.5 months and 4 years) with the findings of septic shock without disseminated intravascular coagulopathy and seven children (aged between 1.5 and 6.5 years) with the first attack of idiopathic status epilepticus were compared with those of eight healthy children (aged between 2.5 months and 5 years). Serum free carnitine levels showed a statistically significant decrease in the sepsis (mean 51.5 +/- 19 mg/L) and status epilepticus groups (mean 4.1 +/- 12.4 mg/L) (P = 0.006 and P = 0.001, respectively)when compared with the controls (mean 90.8 +/- 17.2 mg/L)

Antioxidant status in experimental hyperthyrodism: Effect of vitamin E supplementation

Free radical-mediated oxidative stress has been implicated in the genesis and exacerbation of degenerative diseases. In view of the role of oxidative processes in hyperthyroidism, in this study, we investigated the antioxidant status of erythrocytes in experimental hyperthyroidism and the effect of vitamin E supplementation on defense systems. Our findings of significantly increased T-4 and T-3 and undetectable TSH values in thyroxine administered rats confirmed the establishment of hyperthyroidism. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione (GSH) values were found to be significantly increased in hyperthyroid rats in comparison to the control group. Vitamin E supplementation to hyperthyroid rats induced a significant decrease in GSH-Px activity and a significant increase in GSH level. These findings show that hyperthyroidism increases the components of the antioxidant system in the erythrocytes. Furthermore, vitamin E supplementation reduces the burden of oxidative stress in hyperthyroidism