The Hypocholesterolemic Effects of Eryngium carlinae F. Delaroche Are Mediated by the Involvement of the Intestinal Transporters ABCG5 and ABCG8

Abstract

Hypercholesterolemia is a metabolic disorder characterized by a high concentration of cholesterol in the blood. Eryngium carlinae is a medicinal plant used to treat lipid diseases. The goal of this work was to evaluate, in a model of hypercholesterolemia in mice, the hypocholesterolemic effect of a hydroalcoholic extract of E. carlinae and its main metabolite, D-mannitol. Biochemical analyses of serum lipids and hepatic enzymes were performed by photocolorimetry. We performed histopathological studies of the liver and the expression of the intestinal cholesterol transporters Abcg5 and Abcg8 was determined by standard western blot method. Our results showed that hydroalcoholic extract at doses of 100 mg/kg and D-mannitol at doses of 10 mg/kg reduced the concentration of both total cholesterol and non-HDL cholesterol, without altering the concentration of HDL cholesterol and without damage to hepatocytes. Treatment with the extract increased Abcg8 intestinal transporter expression, while D-mannitol decreased the expression of the two Abcg5/Abcg8 transporters, compared with the hypercholesterolemic group. Considering that Abcg5/Abcg8 transporters perform cholesterol efflux, our results demonstrate that the lipid-lowering effect of the hydroalcoholic extract may be associated with the increase of Abcg8 expression, but the hypocholesterolemic effect of D-mannitol is independent of overexpression of these intestinal transporters and probably they have another mechanism of action.