TY - JOUR T1 - Dietary lipid level affects fatty acid composition and hydrolase activities of intestinal brush border membrane in seabass A1 - Cahu,Chantal A1 - Zambonino-Infante,Jose-Luis A1 - Corraze,Genevieve A1 - Coves,Denis AD - IFREMER, Unite Mixte INRA IFREMER Nutr Poissons, F-29280 Plouzane, France. AD - INRA, Unite Mixte INRA IFREMER Nutr Poissons, F-64310 St Pee Sur Nivelle, France. AD - IFREMER, Stn Expt Aquaculture, F-34250 Palavas Les Flots, France. UR - https://archimer.ifremer.fr/doc/00000/901/ DO - 10.1023/A:1007807324809 KW - Membrane lipid KW - Intestine KW - Fish KW - Fatty acids KW - Dietary lipids KW - Brush border hydrolases N2 - Triplicate groups of juvenile seabass (initial weight of 241 g) were fed during 13 weeks three isonitrogenous experimental diets containing different lipid levels, 12% (LL group), 21% (ML group) and 30% (HL group). At the end of the experiment, fish weight gain was similar among the 3 dietary groups. Intestinal brush border membranes were purified for each dietary group; one part of the brush border fraction was dedicated to enzyme assays, the remaining fraction being used for lipid extraction followed by fatty acid analysis. The fatty acid composition of the brush border membrane differed among the 3 groups, although the 3 experimental diets had the same fatty acid composition. The increase in dietary lipid level resulted in a lowering in (n-3) polyunsaturated fatty acid (PUFA) paralleled with an increase in monounsaturated fatty acid. A significant reduction in the brush border enzyme activities, namely alkaline phosphatase, aminopeptidase N, gamma -glutamyl transpeptidase and maltase, was also observed with the elevation of the dietary lipid level. The change in activity of intestinal digestive enzymes, which are membrane-bound proteins, could be attributed to the modification of fatty acid composition and fluidity of the brush border membranes (BBM). Such lowering in PUFA and increase in monounsaturated fatty acid in BBM, concomitant with a decline in membrane enzymatic activity, has been described as a malnutrition indicator in mammals. It raises the question of possible disorders of gut functions in fish fed increasing lipid levels. Y1 - 2000/08 PB - Kluwer JF - Fish Physiology and Biochemistry SN - 0920-1742 VL - 23 IS - 2 SP - 165 EP - 172 ID - 901 ER -