With raising prevalence of obesity, the regulation of human body fat is increasingly relevant. The modulation of fatty acid uptake by enterocytes represents a promising target for body weight maintenance. Recent results demonstrated that the trigeminal active compounds capsaicin, nonivamide, and trans-pellitorine dose-dependently reduce fatty acid uptake in differentiated Caco-2 cells as a model for the intestinal barrier. However, non-pungent alternatives have not been investigated and structural determinants for the modulation of intestinal fatty acid uptake have not been identified so far. Thus, based on the previous results, we synthesized 23 homovanillic acid esters in addition to the naturally occurring capsiate and screened them for their potential to reduce intestinal fatty acid uptake using the fluorescent fatty acid analog Bodipy-C12 in differentiated Caco‑2 cells as an enterocyte model. Whereas pre-incubation with 100 µM capsiate did not change fatty acid uptake by Caco-2 enterocytes, a maximum inhibition of −47% was reached using 100 µM 1‑methylpentyl-2-(4-hydroxy-3-methoxy-phenyl)acetate. Structural analysis of the 24 structural analogues tested in the present study revealed that a branched fatty acid side chain, independent of the chain length, is one of the most important structural motifs associated with inhibition of fatty acid uptake in Caco-2 enterocytes. The results of the present study may serve as an important basis for designing potent dietary inhibitors of fatty acid uptake.
随着肥胖症的普遍增加,对人体脂肪的调节变得越来越重要。肠细胞对脂肪酸摄取的调节代表着一个有前途的目标,用于维持体重。最近的研究结果表明,三叉神经活性化合物辣椒素、非辣椒素和反-佩里托林能够剂量依赖性地减少不同化的Caco-2细胞中的脂肪酸摄取,作为肠屏障的模型。然而,尚未研究非辣椒类替代品,也尚未确定调节肠道脂肪酸摄取的结构决定因素。因此,基于先前的结果,我们合成了23种顺酐酸酯,另外还有自然存在的辣椒素,并对它们进行筛选,以评估它们减少肠道脂肪酸摄取的潜力,使用荧光脂肪酸类似物Bodipy-C12在不同化的Caco-2细胞中作为肠细胞模型。虽然预先孵育100 µM辣椒素不会改变Caco-2肠细胞的脂肪酸摄取,但使用100 µM 1-甲基戊基-2-(4-羟基-3-甲氧基-苯基)乙酸酯达到了最大的抑制效果,抑制率为-47%。在本研究中测试的24种结构类似物的结构分析显示,一个分支的脂肪酸侧链,无论链长如何,都是与抑制Caco-2肠细胞脂肪酸摄取相关的最重要的结构基序之一。本研究的结果可能为设计有效的膳食脂肪酸摄取抑制剂提供重要依据。