Abstract
This study examines the incorporation of highly unsaturated n−3 fatty acids (HUFA) into triacylglycerols (TAG) of brown adipose tissue (BAT), and their effect on the positional distribution of saturated (SFA) and of unsaturated (UFA) 16- or 18-carbon fatty acids. To this end, rats were fed a fish oil diet for up to four weeks. The stereospecific analysis of TAG was based on generation ofsn-1,2- andsn-2,3-acylglycerols by Grignard degradation, followed by synthesis of phosphatidic acid and specific hydrolysis with phospholipase A2. From the end of the first week of fish oil feeding, a steady-state in the fatty acid composition of TAG in BAT was reached. HUFA concentration increased 30-fold, mainly at the expense of n−9 UFA and of SFA. The amount of SFA decreased selectively at position 3, where these fatty acids were progressively replaced by n−3 HUFA. By contrast, the amount of UFA decreased at all positions, and their positional distribution was not affected. About 60% of HUFA was incorporated at position 3. Nearly twice as much 22∶6n−3 was incorporated into TAG than had been previously observed in white adipose tissue (WAT) [Leray, C., Raclot, T., and Groscolas, R. (1993)Lipids 28, 279–284]. At the steady-state, the distribution of HUFA was characterized by high proportions of 22∶6n−3 and 20∶5n−3 in position 3. Moreover, in each position of TAG, a steady level was reached rapidly (within 1 wk). It is concluded that, during fish-oil feeding, fatty acids in TAG of BAT show characteristic time-course changes that lead to a characteristic composition and a tissue-specific positional distribution. This suggests that adipose tissue has its own specificity in controlling the build-up of TAG stores, which is likely to be regulated by the specificity of acylating enzymes as well as molecular rearrangements.
Similar content being viewed by others
Abbreviations
- BAT:
-
brown adipose tissue
- HUFA:
-
20- and 22-highly unsaturated fatty acids
- SFA:
-
saturated fatty acids
- TAG:
-
triacylglycerols
- UFA:
-
16- and 18-unsaturated fatty acids
- WAT:
-
white adipose tissue
References
Hübscher G. (1970) inLipid Metabolism (Wakil, S.J., ed.), pp. 279–370, Academic Press, New York.
Leray, C., Raclot, T., and Groscolas, R. (1993)Lipids 28, 279–284.
Jandacek, R.J., Hollenbach, E.J., Holcombe, B.N., Kuehlthau, C.M., Peters, J.C., and Taulbee, J.D. (1991)J. Nutr. Biochem. 2, 142–149.
Herzberg, G.R. (1991)Can. J. Physiol. Pharmacol. 69, 1637–1647.
Lands, W.E.M. (1992)FASEB J. 6, 2532–2536.
Simopoulos, A.P. (1991)Am. J. Clin. Nutr. 54, 438–463.
Belzung, F., Raclot, T., and Groscolas, R. (1993)Am. J. Physiol. 264, R1111-R1118.
Masoro, E.J. (1977)Ann. Rev. Physiol. 39, 301–321.
Bukowiecki, L.J. (1985)Int. J. Obesity 9 (Suppl. 2), 31–42.
Folch, J., Lees, M., and Sloane-Stanley, G.H. (1957)J. Biol. Chem. 226, 497–509.
Morrison, W.R., and Smith, L.M. (1964)J. Lipid Res. 5, 600–608.
Lands, W.E.M., Morris, A., and Libelt, B. (1990)Lipids 25, 505–516.
Christie, W.W., Moore, J.H., and Gottenbos, J.J. (1974)Lipids 9, 201–207.
Brockerhoff, H., Hoyle, R.J., and Wolmark, N. (1966)Biochim. Biophys. Acta 116, 67–72.
Brockerhoff, H., Hoyle, R.J., and Hwang, P.C. (1967)Biochim. Biophys. Acta 144, 541–548.
Henderson, R.J., Christie, W.W., and Moore, J.H. (1979)Biochim. Biophys. Acta 574, 8–17.
Bjerve, K.S., Daae, L.N.W., and Bremer, J. (1976)Biochem. J. 158, 249–254.
Raclot, T., and Groscolas, R. (1994)Am. J. Clin. Nutr. 60, 72–78.
Fredrikson, G., and Belfrage, P. (1983)J. Biol. Chem. 258, 14253–14256.
Gavino, V.C., and Gavino, G.R. (1992)Lipids 27, 950–954.
Stokes, G.B., Poteat, L.W., and Tove, S.B. (1975)Biochim. Biophys. Acta 380, 245–256.
Coleman, R., and Bell, R.M. (1976)J. Biol. Chem. 251, 4537–4543.
Bugaut, M. (1989)Lipids 24, 193–203.
Chen, Z.Y., and Cunnane, S.C. (1991)FEBS Lett. 280, 393–396.
Raclot, T., and Groscolas, R. (1993)J. Lipid Res. 34, 1515–1526.
Rothwell, H.J., and Stock, M.J. (1979)Nature. London 281, 31–35.
Mercer, S.W., and Trayhurn, P. (1987)J. Nutr. 117, 2147–2153.
Himms-Hagen, J. (1989)Prog. Lipid Res. 28, 67–115.
Cannon, B., and Nedergaard, J. (1985) inNew Perspectives in Adipose Tissue: Structure, Function and Development (Cryer, A., and Van, R.R., eds.) pp. 223–270, Butterworths, London.
Yamazaki, R.K., Shen, T., and Schade, G.B. (1987)Biochim. Biophys. Acta 920, 62–67.
Zhang, Z.J., Wilcox, H.G., Elam, M.B., Castellani, L.W., and Heimberg, M. (1991)Lipids 26, 504–511.
Rustan, A.C., Christiansen, E.N., and Drevon, C.A. (1992)Biochem. J. 283, 333–339.
Willumsen, N., Skorve, J., Hexeberg,S., Rustan, A.C., and Berge, R.K. (1993)Lipids 28, 683–690.
Leyton, J., Drury, P.D., and Crawford, M.A. (1987)Br. J. Nutr. 57, 383–393.
Slakey, P.M., and Lands, W.E.M. (1968)Lipids 3, 30–36.
Author information
Authors and Affiliations
About this article
Cite this article
Raclot, T., Groscolas, R. & Leray, C. Composition and structure of triacylglycerols in brown adipose tissue of rats fed fish oil. Lipids 29, 759–764 (1994). https://doi.org/10.1007/BF02536697
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02536697