Trans-11 Vaccenic Acid Favourably Remodels Whole Body Energy and Endocannabinoid Metabolism During Conditions of Dyslipidemia

  • Author / Creator
    Jacome Sosa, Maria Miriam
  • Introduction: Trans 11-18:1 (vaccenic acid, VA) is the predominant ruminant-derived trans fatty acid (TFA) in the food chain and is also the precursor to endogenous synthesis of cis-9, trans-11 conjugated linoleic acid (CLA). Literature documents numerous health benefits associated with CLA, which is a minor component of natural TFA. A few recent studies have reported hypolipidemic properties of VA. However, independent bioactive properties of VA during dyslipidemia and insulin resistance remain elusive. Objectives: To determine whether VA can enhance the putative hypolipidemic effects of CLA. To investigate whether enriching dairy fat with VA can favourably modulate whole body energy use/storage. Methods and Results: Hypolipidemic effects of dietary supplementation with CLA on dyslipidemia were enhanced by the addition of VA in a rat model of metabolic syndrome (the JCR:LA-cp rat). VA was also found to reduce total body fat (-6%) while stimulating adipose tissue re-distribution (reduced mesenteric fat (-17%) while increasing inguinal fat mass (29%)). VA fortification increased metabolic rate concomitantly with an increased preference for whole body glucose utilization for oxidation and increased insulin sensitivity (lower HOMA-IR index (-59%)). Additionally, VA re-equilibrated intestinal and hepatic lipid homeostasis (reduced TG secretion) while exerting differential transcriptional regulation in both organs. Targeted lipidomic analyses revealed that VA can regulate concentrations of endocannabinoids in a tissue-specific manner. Conclusions: VA has hypolipidemic effects independent of CLA and can favorably modulate whole body energy metabolism and lipid homeostasis when added to a dairy-derived diet. The regulatory effect of VA on the endocannabinoid system may have potential therapeutic applications. Based on these results, enriching dairy products with VA (either naturally or by fortification) may maximize the health value of dairy-derived fats. Findings also support the need for nutrition guidelines focused on eliminating industrial forms of TFA from processed foods, as opposed to all TFA per se.

  • Subjects / Keywords
  • Graduation date
  • Type of Item
  • Degree
    Doctor of Philosophy
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
    • Department of Agricultural, Food, and Nutritional Science
  • Specialization
    • Nutrition and Metabolism
  • Supervisor / co-supervisor and their department(s)
    • Proctor, Spencer D. (Agricultural, Food and Nutritional Science)
    • Vine, Donna F. (Agricultural, Food and Nutritional Science)
  • Examining committee members and their departments
    • Field, Catherine J. (Agricultural, Food and Nutritional Science)
    • Chan, Catherine B. (Agricultural, Food and Nutritional Science)
    • Banni, Sebastiano (Biomedical Sciencer, University of Cagliari)