Reduced hepatic expression of glutathione s-transferases in burned mice.

Abstract

BACKGROUND: Glutathione S-transferases (GSTs) contribute to liver homeostasis and are released into plasma after liver injury. This study investigates the hepatic expression of key GST enzyme subtypes after burn injury. METHODS: Mice were subjected to an 18% total body surface area burn. Expression of mGSTalpha3 and mGSTmu1 was analyzed by reverse-transcriptase polymerase chain reaction and Western blots on liver preparations from burned and control mice. GST catalytic activity was measured by conjugation assays. RESULTS: : In burned animals, mGSTalpha3 mRNA was only reduced at 1 day, whereas mGSTmu1 mRNA decreased at 1 day and at 3 days after injury. Total mGSTmu protein levels decreased at the same time points, whereas total mGSTalpha protein levels did not change. Also, by 3 days, total GST conjugation activity was reduced by 25% (p=0.05). CONCLUSION: Reduced expression of specific alpha and mu GST enzymes after burns correlates functionally with reduced GST activity. Altered GST expression may contribute to liver damage after systemic injury.