title: Conjugated linoleic acids (CLA) as precursors of a distinct family of PUFA.
abstract: One of the possibilities for distinct actions of c9,t11- and the t10,c12-conjugated linoleic acid (CLA) isomers may be at the level of metabolism since the conjugated diene structure gives to CLA isomers and their metabolites a distinct pattern of incorporation into the lipid fraction and metabolism. In fact, CLA appears to undergo similar transformations as linoleic acid but with subtle isomer differences, which may account for their activity in lowering linoleic acid metabolites in those tissues rich in neutral lipids where CLA is preferentially incorporated. Furthermore, c9,t11 and t10,c12 isomers are metabolized at a different rate in the peroxisomes, where the shortened metabolite from t10,c12 is formed at a much higher proportion than the metabolite from c9,t11. This may account for the lower accumulation of t10,c12 isomer into cell lipids. CLA isomers may therefore be viewed as a "new" family of polyunsaturated fatty acids (PUFA) producing a distinct range of metabolites using the same enzymatic system as the other (i.e., n-3, n-6 and n-9) PUFA families. It is likely that perturbation of PUFA metabolism by CLA will have an impact on eicosanoid formation and metabolism, closely linked to the biological activities attributed to CLA.
authors.affiliation: Università degli Studi di Cagliari, Dipartimento di Biologia Sperimentale, Cittadella Universitaria, Cagliari, Italy. banni@unica.it
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Banni
authors.forename: Anna
authors.initials: A
authors.lastname: Petroni
authors.forename: Milena
authors.initials: M
authors.lastname: Blasevich
authors.forename: Gianfranca
authors.initials: G
authors.lastname: Carta
authors.forename: Lina
authors.initials: L
authors.lastname: Cordeddu
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Murru
authors.forename: Maria Paola
authors.initials: MP
authors.lastname: Melis
authors.forename: Anne
authors.initials: A
authors.lastname: Mahon
authors.forename: Martha A
authors.initials: MA
authors.lastname: Belury
mesh_terms: D000818:Animals; D006801:Humans; D007536:Isomerism; D019787:Linoleic Acid / Q000737:chemistry / Q000378:metabolism; D044243:Linoleic Acids, Conjugated / Q000737:chemistry / Q000145:classification* / Q000378:metabolism*; D015227:Lipid Peroxidation; D020675:Peroxisomes / Q000378:metabolism
chemical_list: D044243:Linoleic Acids, Conjugated; D019787:Linoleic Acid
references.citation: Prog Lipid Res. 2001 Jul;40(4):283-98
references.pmid: 11412893
references.citation: J Biol Chem. 1994 Apr 1;269(13):9514-20
references.pmid: 8144536
references.citation: Nutr Cancer. 2002;43(1):52-8
references.pmid: 12467135
references.citation: Annu Rev Nutr. 2001;21:193-230
references.pmid: 11375435
references.citation: Biochim Biophys Acta. 2004 Jun 1;1682(1-3):120-7
references.pmid: 15158763
references.citation: Annu Rev Nutr. 2002;22:505-31
references.pmid: 12055356
references.citation: J Clin Invest. 1980 May;65(5):1003-12
references.pmid: 6767738
references.citation: J Lipid Res. 2001 Oct;42(10):1521-42
references.pmid: 11590208
references.citation: J Lipid Res. 2001 Jul;42(7):1056-61
references.pmid: 11441132
references.citation: Carcinogenesis. 1999 Jun;20(6):1019-24
references.pmid: 10357782
references.citation: Lipids. 2001 Jun;36(6):575-82
references.pmid: 11485160
references.citation: Arch Biochem Biophys. 1987 Jan;252(1):269-76
references.pmid: 2880562
references.citation: J Nutr. 2003 Jan;133(1):257S-260S
references.pmid: 12514304
references.citation: Curr Opin Lipidol. 2002 Jun;13(3):261-6
references.pmid: 12045395
references.citation: J Biol Chem. 1990 Mar 15;265(8):4369-73
references.pmid: 2307669
references.citation: J Biol Chem. 1999 Jan 15;274(3):1313-9
references.pmid: 9880501
references.citation: J Clin Invest. 1990 Apr;85(4):1173-81
references.pmid: 2318972
references.citation: Biochim Biophys Acta. 1997 Mar 10;1345(1):5-10
references.pmid: 9084496
references.citation: J Biol Chem. 1994 Feb 11;269(6):4103-9
references.pmid: 8307970
references.citation: J Lipid Res. 1995 Nov;36(11):2433-43
references.pmid: 8656081
references.citation: Biochim Biophys Acta. 1988 Sep 2;962(1):122-30
references.pmid: 3416002