Clayton P T, Whitfield P, Iyer K
Biochemistry Unit, Institute of Child Health, London, United Kingdom.
Nutrition. 1998 Jan;14(1):158-64. doi: 10.1016/s0899-9007(97)00233-5.
Long-term parenteral nutrition of infants who have had major gut resections is associated with a high incidence of cholestatic liver disease. Affected infants have high plasma concentrations of phytosterols--compounds that resemble cholesterol but have an alkylated side chain. The phytosterols that accumulate in patients receiving parenteral nutrition are derived from the soya oil and/or soya lecithin used to make the intravenous lipid emulsion. There is a striking association between phytosterolemia and cholestatic liver disease. This has led us to put forward the hypothesis that phytosterols can cause cholestasis in susceptible infants. Experiments using neonatal piglets indicate that phytosterols (given without any of the other components of parenteral nutrition) can indeed reduce bile flow. We suggest that increasing the content of phytosterols in cell membranes may interfere with the function of important transport proteins involved in the secretion of bile. Other factors that might contribute to cholestasis (such as inhibition of cholesterol 7 alpha-hydroxylase) are discussed.
接受大面积肠道切除的婴儿长期进行肠外营养与胆汁淤积性肝病的高发病率相关。受影响的婴儿血浆中植物甾醇浓度很高，植物甾醇是一种类似于胆固醇但具有烷基化侧链的化合物。接受肠外营养的患者体内积累的植物甾醇来源于用于制备静脉脂质乳剂的大豆油和/或大豆卵磷脂。植物甾醇血症与胆汁淤积性肝病之间存在显著关联。这使我们提出假说，即植物甾醇可导致易感婴儿发生胆汁淤积。使用新生仔猪进行的实验表明，植物甾醇（在没有肠外营养的任何其他成分的情况下给予）确实会减少胆汁流量。我们认为，增加细胞膜中植物甾醇的含量可能会干扰参与胆汁分泌的重要转运蛋白的功能。还讨论了可能导致胆汁淤积的其他因素（如抑制胆固醇7α-羟化酶）。
