Abstract

Lipopolysaccharide (LPS), the major component of the outer membran of Gram-negative bacteria, can reproduce neuroinflammation and leads to oxidative stress in brain. Becausetaurine exhibits antioxidative properties, in this study, we aimed to evaluate the protective effects of taurine at the subtoxic dose of lipopolysaccharide-induced lipid peroxidation and oxidative stress. We measured malondialdehyde (MDA), gluthathione (GSH) and nitrite + nitrate (NOx) levels of different brain regions in rats after the i.p administration of LPS and taurine. Wistar male rats (220 to 300 g) were divided into five groups: 1. Control; 2. Saline + LPS (500 μg/kg, i.p.); 3. LPS (500 μg/kg, i.p.) + LPS (500 μg/kg, i.p.); 4. LPS (500 μg/kg, i.p.) + taurine (500 mg/kg, i.p.); 5. Taurine (500 mg/kg, i.p.). i.p. LPS was administred 6 h before sacrification. Taurine was administered after 3 h of LPS injection and the animals sacrified after 3 h of taurine administration. Hippocampus, temporal cortex, frontal cortex, parietal cortex, basal forebrain, cerebellum and brain stem were dissected. MDA, GSH and NOx levels were assayed spectrophotometrically. MDA levels were found increased significantly in all mentioned brain regions after i.p. LPS (p<0.05) except basal forebrain. In LPS + taurine group, we found significantly decreased MDA levels in all mentioned brain regions except an insignificant decrease in cerebellum after i.p. LPS administaration. These results demonstrate that taurine administration with LPS protects brain against LPS-induced lipid peroxidation and oxidative stress.

Key words: Lipopolysaccaride, taurine, lipid peroxidation, nitric oxide, brain.