Effect of Resistant Maltodextrin on Digestion and Absorption of Lipids

Abstract

In order to confirm the mechanism how postprandial elevation of triacylglycerol is suppressed by resistant maltodextrin (Fibersol-2), we conducted the following experiments. Firstly, Rats were fed a high-fat diet with resistant maltodextrin at 0% (control), 2.5% or 5% for 5 weeks to determine the lipid amount excreted in the feces of the last three days. The total lipid and triacylglycerol excreted in rat feces were significantly increased in a dose-dependent manner by the ingestion of resistant maltodextrin. Secondly, 10 healthy adult subjects were administrated a beverage containing 5 g resistant maltodextrin or placebo for 10 days, and crossed over after an 11-day washout. Total lipid excreted in feces was determined by collecting all the feces for the last three days. Fecal weight and fecal lipid amount of the subjects increased significantly with the ingestion of resistant maltodextrin compared to the placebo ingestion. Thirdly, oil emulsion prepared with resistant maltodextrin was assessed for its hydrolysis rate by lipase. The hydrolysis rate of lipid by lipase was not affected by resistant maltodextrin. Lastly, micelle emulsion was prepared with or without resistant maltodextrin, and their stability was compared. Resistant maltodextrin inhibited the decomposition of micelles and stabilized micellar structure. From these results, it was suggested that resistant maltodextrin suppresses lipid absorption and promotes the excretion of lipid into feces by delaying the release of fatty acids from micelles in the lipid absorption process. No inhibitory effect on lipase activity was observed by resistant maltodextrin.

Resistant Maltodextrin Decreases Micellar Solubility of Lipids and Diffusion of Bile Salt Micelles and Suppresses Incorporation of Micellar Fatty Acids into Caco-2 Cells

“…Glycerin was purchased from Wako Pure Chemical Industries, Ltd. (Tokyo, Japan). [1][2][3][4][5][6][7][8][9][10][11][12][13][14] C]Oleic acid was purchased from Amersham Pharmacia Biotech (Tokyo, Japan). High oleic safflower oil is a product of Nisshin Oillio (Tokyo, Japan).…”

“…During semiconfluence, the cells were reseeded on a presoaked membrane filter coated with collagen (Transwell-COL, Corning Costar) and grown to full confluence, according to the method in our previous study (13). A bile salt micellar solution containing 0.5 mm MO, 1 mm oleic acid, [1][2][3][4][5][6][7][8][9][10][11][12][13][14] C] oleic acid, 0.6 mm PC, 0.1 mm cholesterol, 6.6 mm sodium taurocholate, alone (control) or plus 40 mg/ mL RMD was prepared in DMEM by sonication. After filtration through a 0.22-mm filter, 1.5 mL of the micellar solution supplemented with 10% FBS was added to the apical side of differentiated Caco-2 cells and 2.5 mL DMEM was added to the basolateral side.…”

“…8, the incorporation of [1][2][3][4][5][6][7][8][9][10][11][12][13][14] C] oleic acid into Caco-2 cells was significantly smaller in the RMD-containing micelles than that in the control micelles after both 30-and 60-min incubation. Less than 0.65% of the radioactivity added as micellar solutions was secreted to the basolateral side, and no difference was observed between the control and RMD-containing micelles.…”

“…Recently, Kishimoto et al (5) reported that postprandial blood TAG elevation is significantly suppressed in rats treated orally with a fat emulsion containing RMD and in humans given RMD after a meal. They also showed that dietary RMD increases fecal excretion of fat in rats and humans without inhibiting pancreatic lipase activity (6). The results suggest that RMD suppresses lipid absorption in rats and humans.…”

“…When the diffusion rate of bile salt micelles through a filter membrane was investigated in vitro, bile salt micelles containing RMD diffused more slowly than those without RMD. Incorporation of [1][2][3][4][5][6][7][8][9][10][11][12][13][14] C] oleic acid into Caco-2 cells from the RMD-containing bile salt micelles was significantly smaller than that from the control micelles (without RMD). These results show that RMD suppresses intestinal absorption of lipids by decreasing their micellar solubility and the diffusion rate of bile salt micelles.…”