Positional distribution on n−3 fatty acids in triacylglycerols from rat adipose tissue during fish oil feeding

Lipids ◽  
1993 ◽  
Vol 28 (4) ◽  
pp. 279-284 ◽  
Author(s):  
Claude Leray ◽  
Thierry Raclot ◽  
René Groscolas
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fish Oil ◽  
Positional Distribution ◽  
Rat Adipose Tissue

scholarly journals Triacylglycerol biosynthesis in rat adipose-tissue homogenates

1976 ◽  
Vol 159 (3) ◽  
pp. 571-577 ◽  
Author(s):  
W W Christie ◽  
M L Hunter ◽  
R G Vernon
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Oleic Acid ◽  
Linoleic Acid ◽  
Stearic Acid ◽  
Palmitic Acid ◽  
Positional Distribution ◽  
Triacylglycerol Biosynthesis ◽  
Tissue Homogenates ◽  
Rat Adipose Tissue

The optimum cofactor requirements for triacylglycerol biosynthesis in rat adipose-tissue homogenates containing mitochondrial, microsomal and cytosolic fractions were investigated. In general the optimum concentrations of cofactors for triacylglycerol biosynthesis were found to differ from those for total fatty acid esterification. The results provided further evidence for the key role of phosphatidate phosphohydrolase in the regulation of triacylglycerol biosynthesis. Albumin was included in the incubation medium to permit the use of concentrations of added fatty acids that would swamp the effects of endogenous fatty acids. The addition of albumin had little effect on the incorporation of palmitic acid and stearic acid into lipids including triacylglycerols. By contrast, a critical concentration of albumin (about 60 μM) was required before incorporation of oleic acid or linoleic acid into triacylglycerols occurred. The system was used to study the incorporation of different 1-14C-labelled fatty acids from a mixture of unesterified fatty acids [palmitic acid 30%; stearic acid 10%; oleic acid 40%; linoleic acid 20% (molar percentages)] separately into the positions 1,2 and 3 of triacyl-sn-glycerols. In general the stereo-specific distribution of the labelled fatty acids incorporated into triacylglycerols paralleled the normal distribution of fatty acids within rat adipose-tissue triacylglycerols, suggesting that the specificities of the relevant acyltrasferases have the major role in determining the positional distribution of fatty acids within triacylglycerols.

The effects of fat source and breed on the fatty acid composition of lamb muscle and adipose tissue

1999 ◽  
Vol 1999 ◽  
pp. 115-115 ◽  
Author(s):  
A.M. Wachira ◽  
L.A. Sinclair ◽  
R.G. Wilkinson ◽  
G. Demirel ◽  
M. Enser ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Vitamin E ◽  
Fish Oil ◽  
Acid Composition ◽  
Previous Experiment ◽  
Dietary Pufa ◽  
Long Chain

The benefits of long chain polyunsaturated fatty acids (PUFA) to human health, especially those of the n-3 series are now widely recognised. In a previous experiment (Wachira et al. 1998) supplementing diets with whole linseed or fish oil increased n-3 fatty acid levels in lamb muscle. To raise these further the whole linseed can be treated with formaldehyde to increase protection in the rumen. Dietary antioxidants such as vitamin E can control lipid oxidation but information on their effects on lamb performance and fatty acid composition is limited. The current experiments investigated the effects of different dietary PUFA sources and vitamin E levels on growth and fatty acid composition in two sheep breeds. Detailed results of the effects of vitamin E are presented in the accompanying abstract by Enser et al.

Perfusion of rat adipose tissue

1963 ◽  
Vol 205 (2) ◽  
pp. 405-412 ◽  
Author(s):  
André Robert ◽  
Robert O. Scow
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Protein Composition ◽  
Fat Pad ◽  
Edema Formation ◽  
Fatty Acid Release ◽  
Flow Through ◽  
Acid Release ◽  
Rat Adipose Tissue ◽  
Fasted Rats

A technique is described for perfusing the parametrial fat pad of the rat. The rate of flow through the tissue was dependent on temperature, pressure, and the protein composition of the perfusing fluid. The latter also had a pronounced effect on the rate of edema formation in the tissue. The rate of fatty acid release by perfused adipose tissue was affected by the nutritional state of the fat donor and by the composition of the perfusing fluid. Tissue from fed rats did not release fatty acids. Adipose tissue from fasted rats released fatty acids when the tissue was perfused with diluted blood (1.10) or 4% albumin solution but not when perfused with 8% albumin. Perfused tissue released fatty acids at a much faster rate than did incubated tissue. Diluted blood and serum inhibited the release of fatty acids by incubated adipose tissue.

Microsomal glycerolphosphate acyltransferase inactivation by fatty acids

1990 ◽  
Vol 68 (9) ◽  
pp. 1255-1260 ◽  
Author(s):  
V. Durocher ◽  
M. Miller ◽  
M. A. Rodriguez
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Serum Albumin ◽  
Membrane Lipids ◽  
Lipid Synthesis ◽  
Acyltransferase Activity ◽  
Molar Ratios ◽  
Rat Adipose Tissue

Glycerolphosphate acyltransferase activity in microsomes from rat adipose tissue is shown to decrease with time upon incubation with adipose tissue cytosolic fraction. The inactivation can be prevented with serum albumin and seems to be caused by an increase in endogenous free fatty acid as a consequence of the action of cytosolic lipase(s) on the membrane lipids. Similar inactivation can be observed after short incubation of microsomes with oleic acid at micromolar concentrations. Diacylglycerol acyltransferase is also inhibited by oleic acid, although to a lesser degree. In contrast, glucose-6-phosphatase and NADPH – cytochrome reductase activities are not changed. The oleic acid effect appears to occur upon binding to the microsomal membranes and can be prevented by bovine serum albumin at protein/fatty acid molar ratios above one. These results suggest that free fatty acids may be involved in the modulation of triacylglycerol synthetic enzymes.Key words: glycerolphosphate acyltransferase, fatty acids, microsomal enzymes, lipid synthesis.

scholarly journals Effects of dietary n-3 polyunsaturated fatty acids, breed and dietary vitamin E on the fatty acids of lamb muscle, liver and adipose tissue

2004 ◽  
Vol 91 (4) ◽  
pp. 551-565 ◽  
Author(s):  
G. Demirel ◽  
A. M. Wachira ◽  
L. A. Sinclair ◽  
R. G. Wilkinson ◽  
J. D. Wood ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Vitamin E ◽  
Fish Oil ◽  
Live Weight ◽  
Dietary Fatty Acids ◽  
Polar Lipids ◽  
Dietary Vitamin ◽  
Lipid Fractions

The effect of feeding n-3 PUFA on the fatty acid composition of muscle, adipose tissue and liver of lambs was investigated. Groups of eight ram lambs per breed, Suffolk×Lleyn (24kg live weight) and Scottish Blackface (18kg live weight), were each fed one of six diets containing one of three fat sources (50g fatty acids/kg DM; Megalac® (calcium soap of palm fatty acid distillate; Volac Ltd, Royston, Herts., UK) and formaldehyde-treated whole linseed (Trouw Nutrition UK, Northwich, Ches., UK) either alone or with fish oil (1:1, w/w) and either 100 or 500mg α-tocopheryl acetate/kg DM. Feed was offered ad libitum until slaughter at approximately half breed mature live weight. The type of dietary fat had no effect on intake, growth rate or feed conversion ratio. The 3·0-fold higher concentration of 18:3n-3 in the linseed compared with the Megalac® diet approximately doubled (P<0·001) the concentration in the neutral and polar lipid fractions of musculus semimembranosus and liver, and in adipose tissue it increased 2·5-fold. Feeding protected linseed also increased (P<0·001) concentrations of 20:5n-3 and 22:5n-3 in muscle polar lipids and both lipid fractions of liver. The linseed–fish oil raised the 20:5n-3 concentrations above those for the linseed diet and also increased 22:6n-3. Scottish Blackface lambs had lower concentrations of 18:3n-3 in all lipids compared with Suffolk x Lleyn lambs, but more 20:5n-3 in the polar lipids of muscle and liver. High levels of dietary vitamin E were associated with small decreases in the concentration of monounsaturated fatty acids and increases in PUFA. Linseed raised the PUFA:saturated fatty acid ratios in liver and adipose tissue but not in muscle, and improved the n-6:n-3 fatty acid ratio, as did the linseed–fish oil. Different combinations of dietary fatty acids and better protection against rumen biohydrogenation are required to improve muscle PUFA:saturated fatty acids ratios.

Sign in / Sign up

Export Citation Format

Share Document