Role of free radicals and antioxidants in tuberculosis patients.

ABSTRACT

Background: Severe oxidative stress has been reported in TB patients because of malnutrition and poor immunity. The purpose of this study was to investigate the serum lipid peroxidation products and important free radical scavenging enzymes i.e. superoxide dismutase (SOD), catalase and antioxidant glutathione levels and total antioxidant status in TB patients. Methodology: The subjects for this study comprised of normal human volunteers (NHV,n=25), TB patients (n=100) – including untreated (TB1, n=55), under treatment (TB2, n=30) and after treatment (TB3, n = 15) with anti-tuberculosis therapy (ATT). Results: The levels of lipid peroxidation products malondialdehyde (MDA) were increased significantly in TB1 & TB2 (P<0.001) and also in TB3 (P<0.01); these levels gradually decreased with clinical improvement with ATT. SOD, catalase, glutathione levels and total antioxidant status were decreased significantly in TB1 & TB2 (P<0.001), TB3 (P<0.01) patients in comparison with NHV, these levels gradually increased with clinical improvement with ATT. Oxidative stress was observed in all the TB patients (TB1, TB2, TB3), irrespective of treatment status. Conclusions: The study showed that in TB patients free radical activity is quite high and antioxidant levels are low. A suitable antioxidant therapy may prove beneficial and nutritional antioxidant supplementation may represent a novel approach to fast recovery.