Antioxidant effects of methionine, alpha-lipoic acid, N-acetylcysteine and homocysteine on lead-induced oxidative stress to erythrocytes in rats

Lead, widely used in industry, is a great environmental health problem. Many studies have examined its effects on the health of both humans and animals. Experimental studies have shown that sulphur-containing antioxidants have beneficial effects against the detrimental properties of lead. The present study was designed to investigate markers of oxidative stress (hemoglobin (Hb) in whole blood, malondialdehyde (MDA) in sera; superoxidase dismutase (SOD) and glutathione peroxidise (GSH-Px) in erythrocyte hemolysate and vitamins A and E in plasma) in rats given lead (2000ppm) with or without sulphur-containing antioxidants (L-methionine (Met) (100 mg/kg/day), N-acetylcysteine (NAC) (800 mg/kg/day), L-homocysteine (Hey) (25 mg/kg/day), lipoic acid (LA) (50 mg/kg/day)) in their water for 5 weeks. In the lead group, Hb and plasma vitamin E levels were significantly lower whereas MDA levels were significantly higher compared to controls (p<0.05). Hb levels in lead-methionine and lead-LA groups were significantly higher than the lead group (p<0.01). MDA levels were reduced in all groups compared to the lead group (p<0.01). There was a decrease below control values in erythrocyte SOD (p<0.01) and GSH-Px (p<0.05) levels in the lead-LA group. Plasma vitamin A levels were significantly high in lead-methionine group compared to lead group (p<0.01). In conclusion, the data suggests that oxidative stress induced by lead is reduced by sulphur-containing compounds. (C) 2008 Elsevier GmbH. All rights reserved

Selenium prevents lipid peroxidation in liver and lung tissues of rats in acute swimming exercise

PubMed ID: 25773950Background: Selenium, which is critical for human health, is necessary for various metabolic processes, including thyroid hormone metabolism, protection against oxidative stress, and immune function. Objective: The present study aims to examine how selenium administration affects lipid peroxidation in liver and lung tissues of rats subjected to acute swimming exercise. Methods: The study included 32 Spraque-Dawley adult male rats divided into Group 1 (general control), Group 2 (selenium-administered), Group 3 (swimming), and Group 4 (selenium-administered swimming). MDA and GSH levels were determined in liver and lung tissues. Results: The highest MDA values in the liver and lung tissues were found in group 3 in the study. MDA value in group 4 was higher than those in groups 1 and 2. Group 4 had the highest liver and lung GSH levels. GSH levels in Group 3 were higher than those in groups 1 and 2. Conclusion: Results of the study indicate that acute swimming exercise causes lipid peroxidation in liver and lung tissues, while selenium administration prevents free radical formation by increasing antioxidant activity (Tab. 2, Ref. 26). Text in PDF www.elis.sk

Study of the effect of antiviral therapy on homocysteinemia in hepatitis C virus- infected patients

<p>Abstract</p> <p>Background</p> <p>Hepatitis C virus (HCV) infection is one of the leading causes of chronic liver disease (CLD). About 80% of those exposed to the virus develop a chronic infection. Hyperhomocysteinemia, which is an independent risk factor for atherosclerotic vascular disease and thromboembolism, may develop in HCV-infected patients although altered alanine amino transferase (ALT) enzyme levels are generally associated with damage to liver cells. The gold standard therapy for chronic hepatitis C patients is pegylated interferon combined with an anti-viral drug (ribavirin). The current study aimed to investigate the effect of antiviral therapy on plasma homocysteine (Hcy) levels in HCV patients in addition to other parameters.</p> <p>Methods</p> <p>532 HCV-infected patients and 70 healthy controls were recruited for the study. All patients were subjected to laboratory investigations including HCV-RNA levels, complete blood cell counts, serum levels of homocysteine, ALT, alkaline phosphatase (ALP), lipid profile and liver ultrasonographic examination. The outcome of treatment with pegylated interferon α plus ribavirin treatment and sustained virologic response (SVR) was determined 6–9 months post-therapy.</p> <p>Results</p> <p>Hyperhomocysteinemia was found in 91.35% of HCV-infected patients. The difference in plasma Hcy concentrations reached statistical significance between the patient and control groups. ALT, cholesterol and triglycerides (TGs) levels were found higher than normal in the patients group. After receiving a combined therapy for 24 weeks, 43.66% patients showed an SVR (responders); 30.98% patients were non-responders while 25.35% patients initially responded to therapy but again retrieved positive status of HCV infection six months post-therapy (relapse-cirrhotic patients). The mean levels of plasma Hcy, ALT and ALP were significantly reduced in responders within 10 weeks of therapy when compared with non-responders and relapse-cirrhotic patients.</p> <p>Conclusion</p> <p>Elevated homocysteine levels in serum due to HCV infection can be reduced to normal range with the standard interferon α plus ribavirin treatment. This study highlights the significance of the measurement of serum homocysteine levels in the diagnosis and monitoring of HCV infection treatment in addition to other laboratory parameters.</p