| BACKGROUND Type 2 diabetes is a disease which is characterized by a coordinating effect of both genetic and environmental factors. The pathogenesis behind Type 2 diabetes is a deranged pancreatic islet cell function (insulin deficiency and glucagons excess) and impaired insulin sensitivity (i.e. insulin resistance). The latter is due to several factors as abnormal body fat distribution and obesity. The current concept is based upon the fact that one of the key factors leading to insulin resistance is high level of free fatty acids (FFAs), which may come from fat ingestion and from body lipolysis. Since meals in Asia consist of an increasing fat content, it is pivotal to gain further insight into the influence of so-called "westernized" high fat diet on glucose and lipid homeostasis in type 2 diabetes. Such knowledge will further elucidate aspects of the pathogenesis of the disease and may deliver some possible evidence for clinical treatment.OBJECTIVE To assess the influence of short-term high—fat diet (HFD) on circulating levels of hormones, peptides and substrates during daily life conditions in type 2 diabetes. SUBJECTS AND METODS Nine middle-aged men with solely diet or diet and metformin treated type 2 diabetes participated in the study. The design was an unblinded cross-over design. Each of the subjects randomly received one from two types of isocalorie (2100Kcal/d) standard diet for three consecutive days on two occasions, with a 6-week wash out period in between. The component ratio of fat: carbohydrate: protein was 50%:35%:15% vs. 25% :60%:15% in the (high fat diet)HFD vs. the high carbohydrate diet (HCD). Blood samples from 24 hr during the third day were collected. On the forth day morning, an intravenous glucose tolerance test (IVGTT) was conducted using 25g of glucose.RESULTS According to the determination of 24hrs profile samples, HFD resulted in a markedly increased circulating level of NEFA as compared to HCD (p<0.001). In HFD, almost significant highr (p=0.056) FPG was observed after 72 hour. While circulating insulin levels were comparable between the two diets. HFD was also observed with a higher HDL-C (p<0.05). As assessed by the IVGTT, the first phase insulin response (AIRg) tended to be increased after the HFD (p=0.06), and a trend was also observed in terms of a higher glucose peak in HFD (p=0.144). Prebreakfast and presupper values of serum ghrelin were significantly lower during HFD. Fasting glucagon-like peptide-1 (GLP-1) and glucagon were substantially higher during HFD (p<0.05). The increased response of GLP-1 during breakfast period (shown as incremental area under the curve, Δ AUG) was significantly lower than that of HCD (p=0.01), while Δ AUG of glucagon at the same period conversely tended to be higher in HCD (p=0.11). Fasting levels of adiponectin were unaltered during the two dietary regimens. Fasting IL-10 was higher during HFD (p=0.03), and with less suppressed during the breakfast period (p=0.08). CONCLUSION Three—day high fat diet resulting in significantly increased serum NEFA,...
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