Gum Arabic extracts protect against hepatic oxidative stress in alloxan induced diabetes in rats

Gum Arabic (GA) from Acacia seyal and Acacia senegal is a branched-chain polysaccharide which has strong antioxidant properties, and has been used to reduce the experimental toxicity. Yet, the effects of GA on oxidative stress in type I diabetic rats have not been reported. The aim of the study was to investigate the effects of GA on oxidative stress in Alloxan induced diabetes in rats. The rats were divided into 3 groups (n=20 of each): control group, diabetic group injected with allaoxan, and diabetic group given 15% GA in drinking water for 8 weeks. Oxidative damage to liver tissue was evaluated by measurement of key hepatic enzymes, lipid peroxidation, antioxidant enzymes and expression of oxidative stress genes. Activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were significantly (P<0.05) increased in GA group compared to diabetic and control groups. Treatment of GA decreased liver malondialdehyde (MDA), and increased glutathione (GSH). In addition, GA was significantly (P<0.05) reduced the activities of key liver enzymes, including alanine transaminase (ALT) and aspartate transaminase (AST). SOD, GPx and heat shock protein 70 (HSP70) mRNA were significantly increased in GA group compared to control and diabetic groups. Liver of all diabetic rats showed marked degeneration whereas slight degeneration was observed in GA treated rats compared to control. The results suggest that GA may protect liver by modulating the expression of oxidative stress genes, and thus can improve antioxidant status.