Antioxidant effect of simvastatin throught oxidative imbalance caused by lisdexamfetamine dimesylate.

The present study aims to directly investigate the behavioral and antioxidant effects of simvastatin in a model of bipolar mania induced by lisdexamfetamine dimesylate. Wistar rats were treated for 30 days with simvastatin. On the 24th day after the start of treatment, each rat was administered lisdexamfetamine dimesylate for 7 days. The results suggest that simvastatin combined with lisdexamfetamine dimesylate induced a significant increased locomotion and lisdexamfetamine dimesylate administration causes an oxidative imbalance determined by an increment in lipid peroxidation, protein oxidation and alterations in the activities of antioxidant enzymes in brain areas; moreover, in the presence of simvastatin, most of these effects were prevented. These findings contribute to a better understanding of the critical roles of lisdexamfetamine dimesylate in the treatment of neuropsychiatric disorders, associated with increased oxidative stress and changes in antioxidant enzymatic defense. In view of the central role played by lisdexamfetamine dimesylate, the established antioxidant effect of simvastatin therapy is of major interest.

Hypoxanthine induces oxidative stress in kidney of rats: protective effect of vitamins E plus C and allopurinol.

In the present study, we investigated the in vitro effect of hypoxanthine on the activities of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase, as well as on thiobarbituric-acid-reactive substances (TBA-RS), in the renal cortex and medulla of rats. Results showed that hypoxanthine, at a concentration of 10.0 µM, enhanced the activities of CAT and SOD in the renal cortex of 15-, 30- and 60-day-old rats, enhanced SOD activity in the renal medulla of 60-day-old rats and enhanced TBA-RS levels in the renal medulla of 30-day-old rats, as compared with controls. Furthermore, we also verified the influence of allopurinol (an inhibitor of xanthine oxidase), as well as of the antioxidants, trolox and ascorbic acid on the effects elicited by hypoxanthine on the parameters tested. Allopurinol and/or administration of antioxidants prevented most alterations caused by hypoxanthine in the oxidative stress parameters evaluated. Data suggest that hypoxanthine alters antioxidant defences and induces lipid peroxidation in the kidney of rats; however, in the presence of allopurinol and antioxidants, some of these alterations in oxidative stress were prevented. Our findings lend support to a potential therapeutic strategy for this condition, which may include the use of appropriate antioxidants for ameliorating the damage caused by hypoxanthine.

Protective effect of green tea extract against proline-induced oxidative damage in the rat kidney.

We investigated, in vivo (acute and chronic), the effects of proline on thiobarbituric acid-reactive substances (TBA-RS) and on the activities of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in renal tissues (cortex and medulla) of rats. For acute administration, 29-day-old rats received a single subcutaneous injection of proline (18.2µmol/g body weight) or an equivalent volume of 0.9% saline solution and were sacrificed 1h later. For chronic treatment, proline was injected subcutaneously in the rats twice a day from the 6th to the 28th day of age, and the animals were killed 12h after the last injection. The results showed that acute administration of proline enhanced CAT, SOD and GSH-Px activities, as well as, TBARS in the cortex and decreased CAT activity in the medulla, while chronic treatment increased the activities of SOD in the cortex and increased CAT, SOD and GSH-Px in the medulla of rats. Furthermore, the green tea extract treatment for one week or from the 6th to the 28th day of age prevented the alterations caused by acute and chronic, respectively, proline administration. Herein, we demonstrated that proline alters antioxidant defenses and induces lipid peroxidation in the kidney of rats and the green tea extract was capable to counteract the proline-induced alterations.