Dietary 1-monoolein decreases postprandial GIP release by reducing jejunal transport of glucose and fatty acid in rodents

Abstract

-Postprandial secretion of insulin and glucose-dependent insulinotropic polypeptide (GIP) is differentially regulated by not only dietary carbohydrate but also fat. Recent studies have shown that the ingestion of diacylglycerol (DAG) results in lower postprandial insulin and GIP release than that of triacylglycerol (TAG), suggesting a possible mechanism for the antiobesity effect of DAG. The structural and metabolic characteristics of DAG are believed to be responsible for its beneficial effects. This study was designed to clarify the effect of 1-monoacylglycerol [oleic acid-rich (1-MO)], the characteristic metabolite of DAG, on postprandial insulin and GIP secretion, and the underlying mechanism. Dietary 1-MO dose dependently stimulated whole body fat utilization, and reduced high-fat diet-induced body weight gain and visceral fat accumulation in mice, both of which are consistent with the physiological effect of dietary DAG. Although glucose-stimulated insulin and GIP release was augmented by the addition of fat, coingestion of 1-MO reduced the postprandial hormone release in a dose-dependent manner. Either glucose or fatty acid transport into the everted intestinal sacs and enteroendocrine HuTu-80 cells was also reduced by the addition of 1-MO. Reduction of either glucose or fatty acid transport or the nutrient-stimulated GIP release by 1-MO was nullified when the intestine was pretreated with sodium-glucose cotransporter-1 (SGLT-1) or fatty acid translocase (FAT)/CD36 inhibitor. We conclude that dietary 1-MO attenuates postprandial GIP and insulin secretion by reducing the intestinal transport of the GIP secretagogues, which may be mediated via SGLT-1 and FAT/CD36. Reduced secretion of these anabolic hormones by 1-MO may be related to the antiobesity effect of DAG.FAT/CD36; indirect calorimetry; insulin; intestinal transport; SGLT-1 THE WIDESPREAD PREVALENCE of obesity is now a worldwide health problem. Excess adiposity, especially excess abdominal fat accumulation, increases the risk of morbidity from a number of diseases, including diabetes, hypertension, and cardiovascular diseases and is also associated with a greater risk for certain cancers (25). Therefore, improvement of lifestyle, particularly dietary content, is often recommended for the primary prevention and treatment of these diseases. Diacylglycerol (DAG), which consists of 1,3-DAG and 1,2(2,3)-DAG is contained in natural edible oils at a level of 2-10% (8) and is consumed in the daily human diet. Prior studies in animals and humans have shown that dietary DAG oil composed mainly of 1,3-DAG leads to the suppression of body fat accumulation, body weight loss, improved glucose tolerance, and lower postprandial lipemia compared with that of triacylglycerol (TAG), which has a similar fatty acid composition (32, 39). Recent studies have shown that the ingestion of a 1,3-DAG-rich diet results in a lower postprandial insulin response than that of TAG oil in humans (33, 40). Since a high-level postprandial insulin response has been shown to be associate...

Triterpene alcohols and sterols from rice bran lower postprandial glucose-dependent insulinotropic polypeptide release and prevent diet-induced obesity in mice

“…The ablation of GIP-secreting K cells enhanced energy expenditure and reduced HF diet-in- duced obesity in mice (3). Our recent study showed that RS4-type resistant starches and 1-monoolein reduced postprandial GIP and insulin responses, resulting in an increase in fat utilization and reduced HF diet-induced obesity in mice (36,37). The present results are consistent with the findings of previous studies and suggest that the reduction in postprandial blood GIP levels by TASP enhanced fat utilization, thereby preventing HF diet-induced obesity.…”

“…In contrast, we previously demonstrated that the increase in blood GIP levels induced by the chronic administration of GIP decreased fat utilization in high-fat diet-fed mice (37). Our previous studies also revealed that the administration of dietary components that lowered postprandial blood GIP levels, such as diacylglycerol (35), 1-monoolein (36), and RS4-type resistant starch (37) increased fat catabolism and prevented high-fat diet-induced obesity in mice. Postprandial fat utilization was higher with the intake of either diacylglycerol (35) or RS4 (37) than with its equivalent control oil or carbohydrate in humans.…”

“…The human intestinal epithelial cell line, HuTu-80 cells (Cell Lines Service, Eppelheim, Germany) transfected with human SGLT-1 (36), was used in the present study. Cells were seeded into 12-well plates at 5 ϫ 10 5 cells/well and grown to 95-100% confluence.…”

Comparative in vitro intestinal digestion of 1,3-diglyceride and 1-monoglyceride rich oils and their mixtures

“…On the other hand, the use of MG as a regulator in postprandial insulin level has been patented (Takeno, Shimotoyodome, & Meguro, 2009). Recently, Shimotoyodome et al (2012) reported that dietary 1-monoolein stimulated fat utilization, and attenuated induced obesity, postprandial lipemia and insulin response in mice.…”

Dietary steamed wheat bran increases postprandial fat oxidation in association with a reduced blood glucose-dependent insulinotropic polypeptide response in mice

“…In contrast, intravenous administration of GIP to healthy lean men lowers resting energy expenditure (REE) [26]. In our previous study, we found that the dietary components that control GIP secretion, such as diacylglycerol [27], 1-monoolein [28], and RS4-type-resistant starch [29], increase postprandial fat utilization and prevent high-fat diet-induced obesity in mice. Reduction of postprandial GIP secretion can increase postprandial energy catabolism and prevent obesity.…”