C. Toskulkao et al., INHIBITORY EFFECT OF STEVIOL, A METABOLITE OF STEVIOSIDE, ON GLUCOSE-ABSORPTION IN EVERTED HAMSTER INTESTINE IN-VITRO, Toxicology letters, 80(1-3), 1995, pp. 153-159
The effects of stevioside and steviol (a product of enzymatic hydrolys
is of stevioside) on intestinal glucose absorption were examined in ha
mster jejunum. By using the everted sac technique, we found that stevi
oside (1 and 5 mM) had no inhibitory effect on glucose absorption. In
contrast, glucose absorption was inhibited 29% by 1 mM steviol. The in
hibition of glucose absorption by steviol was related to steviol conce
ntration and incubation time. The possible mechanism of steviol inhibi
tory action of glucose absorption was also investigated. Reductions in
the intestinal mucosal ATP content and absorptive surface area were r
esponsible for the inhibition of glucose absorption by steviol. The de
crease in the intestinal mucosal ATP content was accompanied by a decr
ease in the activities of mitochondrial NADH cytochrome c reductase an
d cytochrome oxidase. Morever, no inhibitory effects of steviol on the
activity of intestinal Na+,K+-ATPase and glucose uptake in the intest
inal brush-border membrane vesicles were seen. These results suggest t
hat inhibition of intestinal glucose absorption by steviol in hamsters
is due to the reduction in mucosal ATP content and an alteration of t
he morphology of the intestinal absorptive cells.