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Fat Digestion (fat + digestion)
Selected AbstractsPancreatic enzyme replacement therapy: exocrine pancreatic insufficiency after gastrointestinal surgeryHPB, Issue 2009J. Enrique Domínguez-Muñoz Abstract Exocrine pancreatic insufficiency (EPI) and resultant maldigestion occurs in up to 80% of patients following gastric, duodenal or pancreatic surgery. Accurate diagnosis is required to determine the appropriate intervention, but the conventional method of faecal fat quantification is time-consuming and not always readily available. The optimized 13C-mixed triglyceride (13C-MTG) breath test is an accurate alternative post-surgery. Pancreatic enzyme replacement therapy (PERT) is indicated post-surgery in patients with clinically evident steatorrhoea, weight loss or maldigestion-related symptoms. Given its favourable safety profile, PERT is also appropriate in asymptomatic patients with high faecal fat excretion as such patients are at high risk for nutritional deficits. However, published data evaluating PERT in this setting are limited. Uncoated powder preparations may be preferred in cases of low gastric acidity and partial or total gastric resection. In clinical studies, enteric-coated microspheres were associated with greater weight gain after surgery vs. uncoated preparations. This was confirmed in a recent study using the 13C-MTG breath test; fat absorption increased from <40% without therapy to almost 60% with enteric-coated minimicrospheres (40 000 lipase units/meal), with >60% of patients achieving normal breath test results (i.e. normal fat digestion) during PERT. A therapeutic algorithm for the treatment of EPI after surgery is also discussed. [source] Effect of sodium phytate supplementation on fat digestion and cholesterol metabolism in female ratsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 11-12 2005C. Yuangklang Summary The effects of sodium phytate supplementation on fat digestion and cholesterol metabolism were investigated in female rats. On the basis of an in vitro experiment showing that phytate raised the solubility of bile acids, it was predicted that phytate feeding would depress faecal bile acid excretion, raise apparent fat digestibility and elevate serum cholesterol concentrations. The experimental diets with or without sodium phytate were either cholesterol-free or cholesterol-rich and had a normal calcium concentration. Rats fed on the cholesterol-rich diet with sodium phytate showed enhanced faecal bile acid excretion, but there was no effect on fat digestibility. In rats fed the cholesterol-free diets, phytate did neither affect fat digestion nor bile acid excretion. Sodium phytate inclusion in the cholesterol-rich diet raised serum cholesterol concentrations, but reduced liver cholesterol concentration. Thus, the in vivo data do not agree with the in vitro observations. Both phytate and cholesterol feeding influenced mineral and trace element metabolism. Liver zinc concentrations were raised by phytate feeding. Cholesterol consumption reduced hepatic concentrations of copper, iron and zinc. Both phytate and cholesterol feeding reduced the apparent absorption of calcium, magnesium and phosphorus. [source] Advantages of deuterium-labelled mixed triacylglycerol in studies of intraluminal fat digestionRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 2 2006Christine Slater The 13C-mixed triacylglcerol (MTG, 1,3-distearyl, 2-[1- 13C]octanoyl glycerol) breath test is a non-invasive measure of intraluminal fat digestion. Recovery of 13C in breath CO2 is incomplete (<50%) owing to sequestration of 13C into organic molecules via the tricarboxylic acid (TCA) cycle. In addition lack of knowledge of CO2 production rate (VCO2) during the test leads to errors in the calculated percentage dose recovered (PDR). 2H sequestration into organic molecules is low (,4%) and is not influenced by factors that affect VCO2 such as food intake or physical activity. After oxidation of 2H-labelled macromolecules, the label appears in body water, which can be sampled non-invasively in urine or saliva. After an overnight fast, two healthy adults consumed [2H]MTG (1,3-distearyl, 2-[2H15]octanoyl glycerol) and [13C]MTG (1,3 distearyl, 2-[1- 13C]octanoyl glycerol) simultaneously. Total body water (TBW) was measured by 18O dilution and also estimated from height and weight. Urine and saliva were sampled at baseline and for 10,h after consumption of the test meal. The abundance of 2HOH and H218O in urine and saliva was measured by continuous-flow isotope-ratio mass spectrometry. Cumulative PDR of 2H and 18O was calculated from the plateau enrichment, which was reached by 6,h in both saliva and urine. Recovery of 2H calculated using measured TBW was compared with that using an estimated value of TBW. Mean recovery of 2H in saliva was 99.3% and in urine was 96.4%. Errors introduced by estimating TBW were <5%. [2H]MTG could provide a simpler, more robust, indirect test of intraluminal fat digestion compared with the 13C-breath test. Further studies are required in pancreatic insufficient patients. Copyright © 2005 John Wiley & Sons, Ltd. [source] The inhibitory effects of berry polyphenols on digestive enzymesBIOFACTORS, Issue 4 2005Gordon J. Mcdougall Abstract The evidence for the effect of polyphenol components of berries on digestive enzymes is reviewed. Anthocyanins inhibit ,-glucosidase activity and can reduce blood glucose levels after starch-rich meals, a proven clinical therapy for controlling type II diabetes. Ellagitannins inhibit ,-amylase activity and there is potential for synergistic effects on starch degradation after ingestion of berries such as raspberries and strawberries, which contain substantial amounts of ellagitannins and anthocyanins. A range of berry polyphenols (e.g. flavonols, anthocyanidins, ellagitannins and proanthocyanidins) can inhibit protease activities at levels which could affect protein digestion in the gastrointestinal tract. In contrast, potential for the inhibition of gastrointestinal lipase activity, a proven therapeutic target for the control of obesity through reduced fat digestion, may be limited to proanthocyanidins. Taking into account the manifold possible synergies for inhibition of starch, protein and/or lipid digestion by the spectrum of polyphenol components present within berry species, the inhibition of digestive enzymes by dietary polyphenols may represent an under-reported mechanism for delivering some of the health benefits attributed to a diet rich in fruit and vegetables. [source] Effect of fat digestion on superior mesenteric artery blood flow in humansCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2007T. Symersky Summary Background and aim:, Intraluminal nutrients stimulate superior mesenteric artery (SMA) blood flow. Of the macronutrients, especially fat affects the magnitude of the SMA blood flow response to a meal. Little is known however on the influence of fat hydrolysis on SMA flow. Methods:, We compared in eight healthy volunteers the SMA flow response (Doppler ultrasonography) to continuous intraduodenal fat perfusion (LCT, 240 kCal h,1) during conditions with normal hydrolysis (placebo, control), increased hydrolysis (pancreatic enzyme supplementation; 50 kU lipase) and impaired hydrolysis (orlistat 240 mg). Results:, Intraduodenal LCT significantly (P<0·01) increased SMA flow in all experiments over basal. The SMA flow response to fat during pancreatic enzyme supplementation (1·49 ± 0·1 l min,1) was significantly (P<0·05) higher compared with placebo (1·11 ± 0·16 l min,1). Lipase inhibition with orlistat did not significantly affect fat stimulated SMA flow compared with placebo: 0·89 ± 0·08 l min,1 versus 1·11 ± 0·16 l min,1. Conclusions:, Administration of pancreatic enzymes significantly increases fat stimulated SMA flow. Fat digest products in the intestinal lumen contribute to the regulation of SMA blood flow. [source] | |||||||||||||