Acyl moieties modulate the effects of phospholipids on β‐carotene uptake by Caco‐2 cells

Abstract

The intestinal absorption of carotenoids is thought to be mediated by the carotenoid assembly in mixed micelles, followed by its transfer into the enterocytes and subsequent secretion to the lymph as chylomicron particles. In the present study we investigated the effects of phospholipids and lysophospholipids with diverse fatty acyl moieties on the uptake of beta-carotene solubilized in mixed micelles by Caco-2 cells. Compared with phospholipid-free mixed micelles (NoPL), those containing long-chain PC inhibited beta-carotene uptake (16:0,18:1-PC approximately equal to 16:0,18:2-PC < 14:0,14:0-PC approximately equal to 16:0, 14:0-PC < 16:0,16:0-PC < NoPL). However, mixed micelles containing medium-chain PC enhanced beta-carotene uptake (NoPL < 8:0,8:0-PC < 12:0,12:0-PC < 10:0,10:0-PC), and short-chain PC did not affect the uptake. Among the lysophosphatidylcholine (LysoPC) class, a marked increase of beta-carotene uptake by medium-to-long-chain LysoPC was observed (NoPL < 12:0-LysoPC < 14:0-LysoPC < 18:1-LysoPC < 16:0-LysoPC), although short-to-medium-chain LysoPC (6:0-LysoPC to 10:0-LysoPC) did not affect beta-carotene uptake. The long-chain 16:0,18:1-PC increased the beta-carotene efflux from cells and drastically changed the beta-carotene UV-visible absorbance spectrum, compared with those of NoPL micelles. The acyl moieties of long-chain PC may interact with the carotenoid in the micelle interior, shifting the beta-carotene partition toward the micellar phase. Medium-chain PC and long-chain LysoPC, which have nearly equivalent hydrophobicities, may enhance beta-carotene uptake through their interaction with the cell membrane.

Bioavailability of Dietary Carotenoids: Intestinal Absorption and Metabolism

“…The promoting effect of lysophosphatidylcholine was correlated with the chain length of fatty acid moiety, with longer chain species showing a higher promoting effect. Unlike ordinary phosphatidylcholine with a long-chain fatty acid, medium-chain phosphatidylcholine, which is not present in biological tissues, showed a promoting effect equivalent to long-chain lysophosphatidylcholine (Yonekura et al 2006). Medium-chain phosphatidylcholine has hydrophile-lipophile balance equivalent to long-chain lysophosphatidylcholine, but at a higher level than longchain phosphatidylcholine.…”

Effects of Mixed Micellar Lipids on Carotenoid Uptake by Human Intestinal Caco-2 Cells

“…12,13) We found that the uptake of carotenoids by human intestinal Caco-2 cells was correlated with their lipophilicity, 14) confirming the simple diffusion mechanism. Furthermore, we have found that various PLs such as longchain phosphatidylcholines (PCs), [14][15][16] medium-chain PCs, 15) and lysophospholipids (lysoPLs) with different polar head groups 16) in mixed micelles markedly affect the uptake of micellar carotenoid by Caco-2 cells. Dietary and biliary lipid components would affect carotenoid uptake by intestinal cells.…”

Fucoxanthin Derivatives: Synthesis and their Chemical Properties

“…We succeeded in inducing different micelle sizes merely based on whether the 3-OH of LF 5 was protected or not by the levulinyl group. The interaction between these compounds fucoxanthin 3 , LevLF 4 , and LF 5 and a bile acid sodium taurocholate was confirmed by the measurements of full width at half maximum FWHM 32 in Table 1. FWHM values of the micelles entries 3 to 8 increased in comparison with the ethanol solutions of each compound 3, 4, and 5 , indicating these compounds formed a complex in the micellar inside.…”