Changes in insulin and corticosterone levels may partly mediate the hypolipidemic effect of guar gum and low-molecular weight pectin in rats

The effects of guar gum and a low-molecular weight pectin (LMM-pectin) on g rowth-rates and postprandial plasma triacylglycerol (TAG), total cholestero l (TCh), glucose, insulin, glucagon and corticosterone levels were investig ated in rats. After 8 days of adaptation, rats were fed diets containing ei ther sucrose (Controls) or experimental fibers for three weeks. Compared wi th controls, rats fed soluble fibers showed a significant decrease of TAG, TCh and insulin concentrations without changes in postprandial blood glucos e levels. Glucagon was up-regulated. Compared to rats fed LMM-pectin, a sig nificant decrease (-61%) of postprandial corticosterone was observed in rat s fed guar gum. It is suggested that the decrease of corticosterone and ins ulin levels may partly explain the more important hypolipidemic effect obse rved in this group. (C) 2001 Elsevier Science Inc. All rights reserved.