The intestinal bioavailability of vaccenic acid and activation of peroxisome proliferator-activated receptor-α and -γ in a rodent model of dyslipidemia and the metabolic syndrome

Authors

  • Ye Wang,

    1. Metabolic and Cardiovascular Disease Laboratory, Molecular and Cell Biology of Lipids Group, Alberta Diabetes and Mazankowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
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  • Maria M. Jacome-Sosa,

    1. Metabolic and Cardiovascular Disease Laboratory, Molecular and Cell Biology of Lipids Group, Alberta Diabetes and Mazankowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
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  • Megan R. Ruth,

    1. Department of Agricultural, Food and Nutritional Science, Alberta Institute for Human Nutrition, University of Alberta, Edmonton, AB, Canada
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  • Yan Lu,

    1. Faculty of Pharmacy, Canadian Centre for Agri-Food Research in Health and Medicine, St. Boniface General Hospital Research Centre, University of Manitoba, Winnipeg, MB, Canada
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  • Jianheng Shen,

    1. Department of Plant Science, University of Saskatchewan, Saskatoon, SK, Canada
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  • Martin J. Reaney,

    1. Department of Plant Science, University of Saskatchewan, Saskatoon, SK, Canada
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  • Shannon L. Scott,

    1. Brandon Research Center, Agriculture and Agri-Food Canada, Brandon, MB, Canada
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  • Michael E. R. Dugan,

    1. Lacombe Research Centre, Agriculture and Agri-Food Canada, Lacombe, AB, Canada
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  • Hope D. Anderson,

    1. Faculty of Pharmacy, Canadian Centre for Agri-Food Research in Health and Medicine, St. Boniface General Hospital Research Centre, University of Manitoba, Winnipeg, MB, Canada
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  • Catherine J. Field,

    1. Department of Agricultural, Food and Nutritional Science, Alberta Institute for Human Nutrition, University of Alberta, Edmonton, AB, Canada
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  • Spencer D. Proctor,

    1. Metabolic and Cardiovascular Disease Laboratory, Molecular and Cell Biology of Lipids Group, Alberta Diabetes and Mazankowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
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  • Donna F. Vine

    Corresponding author
    • Metabolic and Cardiovascular Disease Laboratory, Molecular and Cell Biology of Lipids Group, Alberta Diabetes and Mazankowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
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Correspondence: Dr. Donna F. Vine, Metabolic and Cardiovascular Disease Laboratory, Molecular and Cell Biology of Lipids Group, Alberta Diabetes and Mazankowski Heart Institutes, 4-002H Li Ka Shing Centre for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada

E-mail: donna.vine@ualberta.ca

Fax: 1-780-492–9270

Abstract

Scope

Evidence suggests a neutral to beneficial role of certain trans fatty acids (TFA) from natural ruminant sources. Trans11–18:1 (vaccenic acid, VA), the most predominant ruminant TFA and a precursor to conjugated linoleic acid, has been shown to improve atherogenic dyslipidemia and symptoms of hepatic steatosis in animal models. The objective of this study was to assess the intestinal bioavailability of various VA sources including synthetic free fatty acid (FFA) and natural ruminant triglyceride forms, as well as the mechanistic pathways that mediate VA's bioactivity.

Methods and results

VA acts as a partial agonist to both peroxisome proliferator-activated receptors (PPAR)-α and PPAR-γ in vitro, with similar affinity compared to commonly known PPAR agonists. It was further confirmed that VA at 30 and 100 μM concentrations suppressed cardiomyocyte hypertrophy vitro in a PPAR-α- and PPAR-γ-dependent manner. In vivo, feeding of VA (1%, w/w) resulted in increased mRNA and protein expression of PPAR-γ in the mucosa of JCR:LA-cp rats, a model of the metabolic syndrome (p < 0.01 and p < 0.05, respectively) compared to control. In addition, VA from a triglyceride source had greater intestinal bioavailability in vivo compared to VA provided in an FFA form (p < 0.01).

Conclusion

The activation of PPAR-α- and PPAR-γ-dependent pathways provides a mechanistic explanation of how VA improves blood lipids and related metabolic disorders during conditions of hyperlipidemia. This report also supports the consideration of differential reporting of industrially produced versus natural TFA on food nutrient labels.

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