Combined administration of taurine and meso 2,3–dimercaptosuccinic acid in the treatment of chronic lead intoxication in rats

Abstract

The present study describes the dose–dependent effect of taurine, an amino acid and a known antioxidant, either alone or in combination with meso 2,3–dimercaptosucci–nic acid (DMSA) in the treatment of subchronic lead intoxication in male rats. The effects of these treatments in influencing the lead–induced alterations in haem synthesis, hepatic, renal or brain oxidative stress and lead concentration from soft tissues were investigated. Exposure to lead produced a significant inhibition of blood–aminolevulinic acid dehydratase (ALAD) activity, reduction in glutathione (GSH) and an increase in zinc protoporphyrin (ZPP) suggesting an altered haem synthesis pathway. Only DMSA was able to increase the activity of ALAD, while both taurine and DMSA were able to significantly increase GSH level towards normal. Animals treated with taurine significantly reduced the alterations in some of the biochemical parameters indicative of oxidative stress. Thiobarbituric acid reactive substance (TBARS) levels reduced significantly in liver, kidney and red blood cells, while GSH level increased. Activity of superoxide dismutase (SOD) also showed an increase in blood and brain in animals treated with taurine. The data also provided a promising role of taurine during chelation of lead by potentiating the depletion of blood, liver and brain lead compared to DMSA alone. It can thus be concluded from the study that concomitant administration of an antioxidant could play a significant and important role in abating a number of toxic effects of lead when administered along with the thiol chelators.