Ikeda I, Tanabe Y, Sugano M
Laboratory of Nutrition Chemistry, Kyushu University School of Agriculture, Fukuoka, Japan.
J Nutr Sci Vitaminol (Tokyo). 1989 Aug;35(4):361-9. doi: 10.3177/jnsv.35.361.
The influence of sitosterol and sitostanol on the solubility of cholesterol in mixed bile salt micelles in vitro and in vivo was investigated to examine the mechanism by which sitostanol inhibits cholesterol absorption more than does sitosterol. Both sitosterol and sitostanol decreased micellar solubility of cholesterol to a similar extent, when determined with the turbidity. Also, these sterols reduced the concentration of cholesterol in micelles, both in vitro and in vivo. The extent of the reduction of micellar solubility of cholesterol by these sterols was almost the same in vitro, whereas sitostanol tended to reduce the solubility more effectively than sitosterol in vivo. Thus, the interference with cholesterol solubilization in vivo may be responsible for effective inhibition of cholesterol absorption by sitostanol. Since the effect of sitostanol was not observed in vitro, there is a possibility that another factor(s) not included in the in vitro system might affect the action of sitostanol on micellar solubility of cholesterol in vivo.
研究了谷甾醇和谷甾烷醇对胆固醇在混合胆盐微团中体外及体内溶解度的影响，以探究谷甾烷醇比谷甾醇更能抑制胆固醇吸收的机制。用浊度法测定时，谷甾醇和谷甾烷醇均使胆固醇的微团溶解度降低至相似程度。此外，这些甾醇在体外和体内均降低了微团中胆固醇的浓度。这些甾醇在体外降低胆固醇微团溶解度的程度几乎相同，而在体内谷甾烷醇比谷甾醇更倾向于更有效地降低溶解度。因此，在体内对胆固醇溶解的干扰可能是谷甾烷醇有效抑制胆固醇吸收的原因。由于在体外未观察到谷甾烷醇的作用，有可能体外系统中未包含的其他因素可能会影响谷甾烷醇对体内胆固醇微团溶解度的作用。
