Trans-11 vaccenic acid reduces hepatic lipogenesis and chylomicron secretion in JCR:LA-cp rats.
Trans-11 vaccenic acid (VA) is the predominant trans isomer in ruminant fat and a major precursor to the endogenous synthesis of cis9,trans11-conjugated linoleic acid in humans and animals. We have previously shown that 3-wk VA supplementation has a triglyceride (TG)-lowering effect in a rat model of dyslipidemia, obesity, and metabolic syndrome (JCR:LA-cp rats). The objective of this study was to assess the chronic effect (16 wk) of VA on lipid homeostasis in both the liver and intestine in obese JCR:LA-cp rats. Plasma TG (P < 0.001), total cholesterol (P < 0.001), LDL cholesterol (P < 0.01), and nonesterified fatty acid concentrations, as well as the serum haptoglobin concentration, were all lower in obese rats fed the VA diet compared with obese controls (P < 0.05). In addition, there was a decrease in the postprandial plasma apolipoprotein (apo)B48 area under the curve (P < 0.05) for VA-treated obese rats compared with obese controls. The hepatic TG concentration and the relative abundance of fatty acid synthase and acetyl-CoA carboxylase proteins were all lower (P < 0.05) in the VA-treated group compared with obese controls. Following acute gastrointestinal infusion of a VA-triolein emulsion in obese rats that had been fed the control diet for 3 wk, the TG concentration was reduced by 40% (P < 0.05) and the number of chylomicron (CM) particles (apoB48) in nascent mesenteric lymph was reduced by 30% (P < 0.01) relative to rats infused with a triolein emulsion alone. In conclusion, chronic VA supplementation significantly improved dyslipidemia in both the food-deprived and postprandial state in JCR:LA-cp rats. The appreciable hypolipidemic benefits of VA may be attributed to a reduction in both intestinal CM and hepatic de novo lipogenesis pathways.
Wang
Ye
Y
Alberta Institute for Human Nutrition, University of Alberta, Edmonton, AB, Canada.
Jacome-Sosa
M Miriam
MM
Ruth
Megan R
MR
Goruk
Sue D
SD
Reaney
Martin J
MJ
Glimm
David R
DR
Wright
David C
DC
Vine
Donna F
DF
Field
Catherine J
CJ
Proctor
Spencer D
SD
D000103:Acetyl-CoA Carboxylase / Q000378:metabolism; D000818:Animals; D053283:Apolipoprotein B-48 / Q000097:blood; D001835:Body Weight / Q000187:drug effects; D002914:Chylomicrons / Q000187:drug effects* / Q000378:metabolism; D004032:Diet; D004655:Emulsions; D002149:Energy Intake; D064429:Fatty Acid Synthases / Q000378:metabolism; D007263:Infusions, Parenteral; D050155:Lipogenesis / Q000187:drug effects*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008196:Lymph / Q000502:physiology; D009765:Obesity / Q000378:metabolism; D009829:Oleic Acids / Q000008:administration & dosage / Q000494:pharmacology*; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000097:blood / Q000378:metabolism*; D014304:Triolein / Q000378:metabolism / Q000494:pharmacology
D053283:Apolipoprotein B-48; D002914:Chylomicrons; D004655:Emulsions; D009829:Oleic Acids; D014280:Triglycerides; D014304:Triolein; D064429:Fatty Acid Synthases; D000103:Acetyl-CoA Carboxylase; C050413:11-octadecenoic acid