title: Solubility in and affinity for the bile salt micelle of plant sterols are important determinants of their intestinal absorption in rats.
abstract: Intestinal absorption of various plant sterols was investigated in thoracic duct-cannulated normal rats. Lymphatic recovery was the highest in campesterol, intermediate in brassicasterol and sitosterol, and the lowest in stigmasterol and sitostanol. Higher solubility in the bile salt micelle was observed in sitosterol, campesterol, and sitostanol than in brassicasterol and stigmasterol. The solubility of the latter two sterols was extremely low. When the affinity of plant sterols for the bile salt micelle was compared in an in vitro model system, which assessed sterol transfer from the micellar to the oil phase, the transfer rate was the highest in brassicasterol, intermediate in campesterol and stigmasterol, and lowest in sitosterol and sitostanol. Although no significant correlations between lymphatic recovery of plant sterols and their micellar solubility or transfer rate from the bile salt micelle were observed, highly positive correlation was obtained between the lymphatic recovery and the multiplication value of the micellar solubility and the transfer rate. These observations strongly suggest that both solubility in and affinity for the bile salt micelle of plant sterols are important determinants of their intestinal absorption in rats.
authors.affiliation: Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan. tadateru@agr.kyushu-u.ac.jp
authors.forename: Tadateru
authors.initials: T
authors.lastname: Hamada
authors.forename: Hitomi
authors.initials: H
authors.lastname: Goto
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamahira
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugawara
authors.forename: Katsumi
authors.initials: K
authors.lastname: Imaizumi
authors.forename: Ikuo
authors.initials: I
authors.lastname: Ikeda
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000378:metabolism*; D002775:Cholestadienols / Q000493:pharmacokinetics; D002784:Cholesterol / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D007408:Intestinal Absorption / Q000502:physiology*; D008196:Lymph / Q000378:metabolism; D008297:Male; D008823:Micelles; D008954:Models, Biological; D010840:Phytosterols / Q000737:chemistry / Q000302:isolation & purification / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D012855:Sitosterols / Q000493:pharmacokinetics; D012995:Solubility; D013265:Stigmasterol / Q000493:pharmacokinetics; D014304:Triolein / Q000378:metabolism
chemical_list: D001647:Bile Acids and Salts; D002775:Cholestadienols; D008823:Micelles; D010840:Phytosterols; D012855:Sitosterols; D014304:Triolein; C003532:brassicasterol; C021273:campesterol; C025473:gamma-sitosterol; D002784:Cholesterol; D013265:Stigmasterol