Investigation of antioxidant effects of some sulfur-containing compounds on various tissues: oxidative stress induced by lead acetate in rats

2. ABSTRACTINVESTIGATION OF ANTIOXIDANT EFFECTS OF SOME SULFUR-CONTAINING COMPOUNDS ON VARIOUS TISSUES: OXIDATIVE STRESSINDUCED BY LEAD ACETATE IN RATSEmrah ÇAYLAKLead causes a great environmental problem because it is being widely used in theindustry. Several studies focusing its effects on human and animals have been carried out.Sulfur containing antioxidants have been observed to have beneficial effects against lead?sdetrimental properties in experimental studies.Evaluation of antioxidant effects of some sulfur-containing compounds in rats whereoxidative stress was induced by lead acetate was the aim of our study. In addition to controlgroup (n=10), Wistar-Albino male rats were given 2000 ppm lead acetate alone (n=10), orwith daily oral 100 mg/kg L-methionine (n=10), or with 800 mg/kg N-acetylcysteine (n=10),or with 50 mg/kg L-homocysteine (n=10), or with i.p. 25 mg/kg α-lipoic acid (LA) (n=8)during five weeks. Hemoglobin (Hb) levels were analyzed by the cyanomethemoglobinmethod using Drabkin reagent in whole blood whereas superoxide dismutase (SOD) andglutathione peroxidase (GSH-Px) enzyme activities were assayed with commercially availablekits in hemolysate. Malondialdehyde (MDA) levels were determined with method of Satoh-Yagi in sera whereas vitamin A (Vit-A) and vitamin E (Vit-E) levels were determined withHPLC UV detector in plasma. Total antioxidant capacity (TAC) levels in tissue homogenateswere assayed with ABTS.+ method.In lead group Hb and plasma Vit-E levels were determined to be significantly lowwhereas MDA levels were significantly high compared to controls (p<0.01). Hb levels inlead-methionine, lead-LA groups were significantly low compared to lead group (p<0.05).MDA levels were reduced in all groups compared to lead group (p<0.01) whereas there wasan increase over control values in erythrocyte SOD (p<0.01), and GSH-Px (p<0.05) levels inlead-LA group. Plasma Vit-A levels were significantly high in lead-methionine groupcompared to lead group (p<0.01). In all lead-antioxidants groups liver TAC levels weredetermined to be slightly lower compared to lead group while brain?s levels were higher.Kidney TAC levels in lead-methionine, and lead-LA groups were significantly high (p<0.01).In conclusion, in the light of these findings it is believed that oxidative stress inducedby lead is reduced by sulfur-containing compounds.Key words: Lead, oxidative stress, sulfur-containing compounds.