Postprandial Serum Lipids and TissueLipoprotein Lipase are Acutely Altered in Rats by the α-Glucosidase Inhibitor Acarbose

Abstract

The purpose of this study was to evaluate the consequences of the acarbose-induced attenuation of postprandial glycemia and insulinemia on plasma lipid concentrations and on tissue lipoprotein lipase (LPL) activity. Rats were fed a high-sucrose diet ad libitum for two weeks. On the day of the experiment, half of the animals were given a high-sucrose meal, whereas the other half were given acarbose (10 mg/kg body weight) mixed with the meal. Serum lipids and tissue LPL activity were assessed in samples collected one hour after meal intake. Glycemia was comparable in both groups, whereas serum insulin in acarbose-fed rats was half that of control animals. The main effects of acarbose on postprandial lipids consisted of a lowering of triacylglycerols (- 50 %) and non-high density lipoprotein cholesterol. LPL was not altered by acarbose in white and brown adipose tissues, but was higher in the heart (+ 33%). The effects of acarbose on postprandial serum lipids are consistent with a slower rate of de novo lipogenesis from carbohydrate precursors and a consequent lowering of very-low density lipoprotein secretion into the circulation. In addition, the acarbose-induced dampening of the postprandial excursion of insulin may have maintained higher LPL activity in the heart, which would be liable to participate in the hypotriacylglycerolemic action of the inhibitor.