Modulation of Quinone Reductase, Alcohol Dehydrogenase and Cytochrome P450 2E1 Activities in Rat Liver by Aloe arborescens var. natalensis (Kidachi aloe)

We examined the modulating effects of freeze-dried whole-leaf Aloe arborescens var. natalensis (hereinafter called ALOE) on the hepatic activities of quinine reductase (QR), alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH) and cytochrome P450 (CYP) 2E1-mediated p-nitrophenol (PNP) hydroxylase in rats. Male F344 rats (4 weeks old) were fed a basal diet or experimental diets containing 5%ALOE for 5 weeks. Dietary administration of ALOE significantly enhanced the activities of QR and ADH compared with controls. In contrast, the PNP hydroxylase activity was significantly reduced in rats fed the ALOE diet. On the other hand, no significant changes were observed in the ALDH activity in the ALOE-treated rats. These results indicate that ALOE may have beneficial effects on ethanol metabolism and toxicity.