Dose-Responsive Effect of Sub-acute Lead Exposure on Alteration of Carbohydrate Metabolism in Murine Model

Abstract

The dose-responsive effect of sub-acute lead exposure on carbohydrate metabolism was evaluated. Five groups of Swiss albino male mice were formed; a control group and other lead-treated groups; Group A (5 mg/kg body weight), Group B (10 mg/kg body weight), Group C (15 mg/kg body weight) and Group D (20 mg/kg body weight). Lead exposure caused significant reduction in blood and hepatic glucose levels as well as liver glycogen content in a dose-dependent manner; the most remarkable effect was noted in group D. All of the treated groups experienced a considerable decline in glucose 6-phosphatase activity. Dose-dependent increase in pyruvic acid content was found to be associated with decrease in pyruvate dehydrogenase, malate dehydrogenase and transaminase enzyme activities. Additionally, increased free amino acid nitrogen in liver after lead exposure may provide more substrates for gluconeogenesis. So, an adaptive mechanism was initiated by stimulating glycogenolytic and retarding glycolytic activity in liver to recover from the toxic effect of lead.