Study of glutathione metabolism oxidative stress and the effect of vitamin E supplementation in COPD .

Abstract

Oxidative stress has bseen recognized as a central feature of smoke induced chronic obstructive pulmonary disease (COPD). Imbalance between oxidant and glutathione redox cycle is also an established fact in these patients. 60 patients with chronic bronchitis and 60 with Emphysema were include in the study. Their base line clinical examination , malondialdehyde (MDA), alpha tochopherol and glutathione peroxidase (GPx) and glutathione reductase levels were measured. 100 healthy non-smokers were served as controls. All the above parameters were repeated after 8 weeks of supplementation with 400 IU of vitamin E twice daily with regular treatment and without regular treatment. The mean malondialdehyde levels in the patients at base line were high (P< 0.001) than Controls . Plasma alpha-tocopherol , glutathione peroxidase, glutathione reductase levels were low (P<0.001)in the patients compared to controls. Exogenous vitamin E (400 IU twice daily) supplementation along with regular treatment shows slight increase in the enzymes of glutathione redox cycle and vitamin E than regular treatment . The present study shows that initially the plasma lipid peroxide (MDA) levels were high & antioxidants were low in patients with lung disorders. Exogenous supplementation with vitamin E brings down the levels of MD showing attenuation of further damage. Our results suggest the presence of oxidative stress and the augmentation of antioxidant defenses as shown by slight increase in enzymes of redox cycle. However supplementation with vitamin E for longer periods with higher doses may throw more light on free radical injury & protective effects of antioxidants.