Lipid test meal

R17, Rose, H. G., and Juliano, J., Regulation of plasma lecithimcholesterol acyltransferase in man. III. Role of high density lipoprotein cholesteryl esters in the activating effect of a high-fat test meal. J. Lipid Res. 20, 399-407 (1979). 

Different complete test meals containing proteins, carbohydrates and lipids have been tested for measuring digestive hpase secretions and hpolysis levels in the CI tract. Shak Iso (initially from Sopharga Laboratories, later from Nestle Chnical Nutrition, France) was used as a complete hquid test meal. A standard 375 mL... 

The importance of the physical state of the lipids in the meal was demonstrated by measuring in vitro the specific activities of HGL and HPL on the triglycerides of the liquid and the mixed liquid-solid test meals. HPL was found to display a higher activity on the pre-emulsified TG of Shak Iso (43-47 U/mg) than on the TG found in the mixed hquid-solid meal (12-15 U/mg) (Carriere et al., 2000). As will be shown below (section 10.7), these observations were essential to understand the mechanism of hpolysis inhibition by the hpase inhibitor orhstat . 

Duodenal lipolysis level was deduced by subtracting fhe gastric hpolysis level from the overall hpolysis level. Duodenal hpolysis was also found to be lower wifh the solid meal (18.4%) than wifh fhe hquid meal (35.0 2.0% Tab. 10.6). The triglycerides of fhe hquid test meal therefore provided a better substrate for HGL and HPL, probably because they were pre-emusified and stabihzed in fhe form of a fine emulsion by fhe large amounts of phosphohpids present in fhe Shak Iso liquid test meal. In fhe solid meal, fhe physicochemical state of fhe lipids is more heterogeneous and most of fhe TG have to be emulsified in fhe course of the digestion process. 

Collection of duodenal contents through a duodenal tube after feeding a test meal containing a non-absorbable marker is a commonly used technique for studies of lipid digestion and absorption in man [55]. Using a multilumen tube, Simmonds et al. [56] were able to study in detail in man the absorption kinetics of cholesterol from a micellar solution. 

Test meal Emulsion containing test oil (dose of oil = 30 g/m ). Measurements Lipids in serum and remnant-like particles (RLP), apolipoproteins, and LPL protein. 

The best quality oil, low in phosphatides, free fatty acids, nonsaponifiable matter and pigments, is extracted first, while poorer quality lipids are extracted with more exhaustive extraction. The industry, however, strives for the most complete extraction possible. Residual oil contents of finished solvent-extracted soybean meal range 0.5-1.5% (toasting defatted soybean meal liberates oil, and toasted meal will test higher in oil content than do drained untoasted extracted flakes). Some have advocated doing less complete oil extraction to reduce refining costs, but not ail extraction plants have capabilities to alkali refine and, thus, there is little incentive to extraction plants to minimize refining loss. 

Numerous diets have been tested. The best results in A. japonicus were obtained when adults were fed 200-400 g kg protein with 20 g kg lipid (Seo and Lee, 2011). Various elements like soya beans,ground macrophytes, fish meals, mud, lees, yeast and bran are used in combination with mineral and vitamin supplements [developed for A. japonicus in China (Hulling et ah, 2004)]. Some facilities also use a supplement of Algamac (Bio-Marine, Inc., Aquafauna, Hawthorne, CA, USA), or residues from moribund phytoplankton cultures. Finally, the broodstock tanks should receive high quality water,preferably unfiltered, and be located to receive some sunlight and moonlight. When reared in covered tanks, I. fuscus was demonstrated to interrupt its natural lunar spawning cycle (Mercier et al., 2007). 

In humans, molar concentrations of chylomicron retinyl esters can exceed those of retinol-RBP by 3- to 4-fold during the 3 to 6 h following consumption of a bolus test dose of retinol [8] or of a retinol-rich meal [7]. For healthy humans, postprandial clearance of chylomicron retinoids normally occurs within 6 to 8 h [4, 8]. However, in some disease states in which clearance of postprandial lipids is delayed, the rate of chylomicron retinoid clearance can be much slower than that of healthy individuals. Chylomicron retinoid clearance in rats and mice is more rapid than in humans, with circulating chylomicron retinyl ester levels reaching a maximum within 2 to 4 h after consumption of retinol [30]. 

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