title: The fraction of α-linolenic acid present in the sn-2 position of structured triacylglycerols decreases in lymph chylomicrons and plasma triacylglycerols during the course of lipid absorption in rats.
abstract: Little is known about the ability of α-linolenic acid (Ln) to remain in the sn-2 position of TG during the absorption process. The goal of this study was to determine the Ln distribution in the lymph (Study 1) and plasma (Study 2) TG of rats fed a single i.g. load of structured TG [300 mg/rat of either oleic acid (O)/Ln/O TG (OLnO) or Ln/O/O TG (LnOO), n = 7 rats]. In an early fraction (3-4 h) of lymph (OLnO group; 100% Ln in the sn-2 position), 46 ± 2% Ln was maintained in this position in lymph TG. There was even less (29 ± 6%) in the last fraction (7-24 h) (P < 0.05). Ln was also found (9 ± 3%) in the sn-2 position of lymph TG in the LnOO group. The Ln content in lymph phospholipids was twice as high in rats when they were fed LnOO (4.2 ± 0.1%) than OLnO (2.3 ± 0.2%) (P < 0.005). Six hours postprandially (Study 2), 21 ± 3% of the Ln incorporated into plasma TG was located in the sn-2 position in the OLnO group compared to 13 ± 2% in the LnOO group (P < 0.001). Overall, these results indicate that the amount of Ln that moved from the sn-2 position of structured TG to the sn-1(3) position of lymph TG increased during absorption. This may account for a substantial hydrolysis of the 2-monolinolenylglycerols in enterocytes, leading to the intramolecular redistribution of Ln in lymph TG and, consequently, in plasma TG.
authors: ITERG, Unité de Nutrition, Métabolisme et Santé, Talence, France.
authors: Leslie
authors: L
authors: Couëdelo
authors: Carole
authors: C
authors: Vaysse
authors: Emilie
authors: E
authors: Vaique
authors: Alexandre
authors: A
authors: Guy
authors: Isabelle
authors: I
authors: Gosse
authors: Thierry
authors: T
authors: Durand
authors: Sandra
authors: S
authors: Pinet
authors: Maud
authors: M
authors: Cansell
authors: Nicole
authors: N
authors: Combe
mesh_terms: D000818:Animals; D002914:Chylomicrons / Q000378:metabolism*; D050356:Lipid Metabolism; D008196:Lymph / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014280:Triglycerides / Q000097:blood / Q000737:chemistry* / Q000378:metabolism; D017962:alpha-Linolenic Acid / Q000032:analysis* / Q000378:metabolism
chemical_list: D002914:Chylomicrons; D014280:Triglycerides; D017962:alpha-Linolenic Acid