Intestinal fatty acid binding protein may favor differential apical fatty acid binding in the intestine
Intestinal fatty acid binding protein may favor differential apical fatty acid binding in the intestine
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DOI：
10.1016/s1388-1981(99)00200-0
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发表时间：
2000-01-31
影响因子：
4.8
通讯作者：
DeSchryver-Kecskemeti, K
中科院分区：
文献类型：
--
作者：
Alpers, DH;Bass, NM;DeSchryver-Kecskemeti, K
当肠粘膜呈现于内腔膜或基底外侧膜时，肠粘膜代谢脂肪酸的方式不同。肝脏和肠道脂肪酸结合蛋白（L-和I-FABP）在肠细胞中的独特表达为这种现象提供了可能的解释。使用器官外植体系统来分析脂肪酸与每种蛋白质的相对结合。无论在哪一侧添加脂肪酸，与L-FABP结合的脂肪酸多于与I-FABP结合的脂肪酸（28% vs. 6%的细胞溶质放射性）。然而，在顶端添加棕榈酸或油酸后，观察到与肠壁结合的脂肪酸增加2-3倍。当顶部加入油酸时，在来自慢性脂肪喂养大鼠的粘膜中观察到与I-FABP结合的1.4倍增加，与先前观察到的该蛋白质含量增加50%一致。两种FABP在体内的免疫细胞化学定位表明，在禁食状态下顶端细胞质定位，脂肪喂养后重新分布到整个细胞质。这些数据是一致的假设，I-FABP可能有助于顶端提出的脂肪酸在肠道中的代谢区室化。(C)2000 Elsevier Science B. V.保留所有权利。
The intestinal mucosa metabolizes fatty acids differently when presented to the lumenal or basolateral membrane. Expression of both liver and intestinal fatty acid binding proteins (L- and I-FABPs) uniquely in the enterocyte offers a possible explanation of this phenomenon. An organ explant system was used to analyze the relative binding of fatty acids to each protein. More fatty acid was bound to L-FABP than to I-FABPs (28% vs. 6% of cytosolic radioactivity), no matter on which side the fatty acid was added. However, a 2-3-fold increase in fatty acid binding to the intestinal paralog was noted after apical addition of palmitic or oleic acid in mucosa from chow fed rats. When oleic acid was added apically, a 1.4-fold increase in binding to I-FABP was observed in mucosa derived from chronically fat fed rats, consistent with the previously observed 50% increase in the content of that protein. Immunocytochemical localization of both FABPs in vivo demonstrated an apical cytoplasmic localization in the fasting state, and redistribution to the entire cytoplasm after fat feeding. These data are consistent with the hypothesis that I-FABP may contribute to the metabolic compartmentalization of apically presented fatty acids in the intestine. (C) 2000 Elsevier Science B.V. All rights reserved.