Elsevier

The Journal of Nutrition

Volume 138, Issue 11, November 2008, Pages 2117-2122
The Journal of Nutrition

Trans-11 Vaccenic Acid Dietary Supplementation Induces Hypolipidemic Effects in JCR:LA-cp Rats12

https://doi.org/10.3945/jn.108.091009Get rights and content
Under an Elsevier user license
open archive

Abstract

Trans-11 vaccenic acid [VA; 18:1(n-9)] is a positional and geometric isomer of oleic acid and is the precursor to conjugated linoleic acid (CLA) in humans. Despite VA being the predominant trans monoene in ruminant-derived lipids, very little is known about its nutritional bioactivity, particularly in conditions of chronic metabolic disorders, including obesity, insulin resistance, and/or dyslipidemia. The aim of this study was to assess the potential of VA to improve dyslipidemia, insulin sensitivity, or inflammatory status in obese and insulin-resistant JCR:LA-cp rats. The obese rats and age-matched lean littermates were fed a control diet or a control diet supplemented with 1.5% (wt:wt) VA for a period of 3 wk. The incorporation of VA and subsequent conversion to CLA in triglyceride was measured in adipose tissue. Glucose and insulin metabolism were assessed via a conscious adapted meal tolerance test procedure. Plasma lipids as well as serum inflammatory cytokine concentrations were measured by commercially available assays. VA supplementation did not result in any observable adverse health effects in either lean or obese JCR:LA-cp rats. After 3 wk of feeding, body weight, food intake, and glucose/insulin metabolism did not differ between VA-supplemented and control groups. The incorporation of VA and CLA into adipose triglycerides in obese rats fed VA increased by 1.5-fold and 6.5-fold, respectively, compared with obese rats fed the control diet. The most striking effect was a 40% decrease (P < 0.05) in fasting triglyceride concentrations in VA-treated obese rats relative to obese controls. Serum Il-10 concentration was decreased by VA, regardless of genotype (P < 0.05). In conclusion, short-term dietary supplementation of 1.5% VA did not result in any detrimental metabolic effects in JCR:LA-cp rats. In contrast, dietary VA had substantial hypo-triglyceridemic effects, suggesting a new bioactivity of this fatty acid that is typically found in ruminant-derived food products.

Abbreviations used:

ALA
α-linolenic acid
AUC
area under the curve
CLA
conjugated linoleic acid
CVD
cardiovascular disease
LA
linoleic acid
MTT
meal tolerance test
VA
trans-11 vaccenic acid

Cited by (0)

1

Supported by the Beef Information Centre (Canada) and the Dairy Farmers of Canada, the Alberta Livestock Industry Development Fund in association with the CLA Network (Canada).

2

Author disclosures: Y. Wang, J. Lu, M. Ruth, S. Goruk, M. Reaney, D. Glimm, D. Vine, C. Field, and S. Proctor, no conflicts of interest.