The effect of feeding maltulose and lactulose on hepatic lipogenic enzyme activities in the rat

Abstract

The effect of feeding maltulose, lactulose, and sucrose (ketose disaccharides) and maltose and lactose (aldose disaccharides) on hepatic lipogenic enzyme activities in the rat was studied. Male Sprague-Dawley rats were starved for 2 days and refed for 2 days diets containing 45% total carbohydrate. Lactulose and lactose were fed at a level of 15% of the diet due to their poor digestibility. Activities of hepatic glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME) were measured. Hepatic G6PD and ME activities in rats fed maltulose were similar to rats fed maltose. Hepatic ME activity was lower in rats fed maltulose than sucrose. Rats fed lactulose had lower G6PD and ME activities than rats fed lactose. The atudy suggests that in the rat lactulose is less utilizable than lactose, and that maltulose is less lipogenic than sucrose.