Effect of glucose-cysteine adduct on cysteine desulfuration in guinea pig tissues

Effect of intraperitoneal administration (12 mmol/kg of body weight) of glucose-cysteine adduct 2-(D-gluco-pentahydroxypentyl)-thiazolidine-4-carboxylate, (glc-cys) on the rhodanese, gamma-cystathionase and 3-mercaptopyruvate sulfurtransferase (MPST) activity levels in guinea pig tissues was studied. The rhodanese activity value in liver increased by 41%, 3-mercaptopyruvate sulfurtransferase by 24%, and gamma-cystathionase by 12% after three successive days of the administration. In the kidney, on the contrary, glc-cys administration resulted in about 18% decrease in the gamma-cystathionase activity value, whereas no changes in MPST and rhodanese activity values were observed. In the case of the brain, rhodanese and gamma-cystathionase did not change their activity but the activity of MPST decreased by 21%. MPST level did not change substantially in whole blood after glc-cys treatment. The results seem to indicate that in guinea pig liver but not in kidney and brain, glc-cys has a potential to activate the desulfuration pathway of L-cysteine metabolism.