title: Dietary trans-vaccenic acid (trans11-18:1) increases concentration of cis9,transll-conjugated linoleic acid (rumenic acid) in tissues of lactating mice and suckling pups.
abstract: Lactating mice were fed trans-vaccenic acid (trans 11-18:1, TVA) to assess desaturation of TVA to cis9,trans11-conjugated linoleic acid (9/11CLA). Diets contained 30 g x kg(-1) 18:2n-6 (LA) or 20 g LA plus 10 g 18:0 (SA), TVA, or a CLA mixture (MCLA). Compared with SA, feeding TVA increased 9/11CLA concentrations in blood plasma phospholipid, triglyceride, and free fatty acid fractions. However, concentrations of 9/11CLA in plasma fractions were greater when MCLA was fed compared with SA or TVA. No 9/11CLA was detected in liver of mice fed SA, and it was only 1 mg x g(-1) of total fatty acids in the carcass. In contrast, 9/11CLA content of liver (5 mg x g(-1)) and carcass (6 mg x g(-1)) of mice fed TVA was similar to liver (5 mg x g(-1)) and carcass (7 mg x g(-1)) of mice fed MCLA. Mammary tissue of SA-fed mice had no detectable 9/11 CLA, compared with 5 or 14 mg x g(-1) for TVA or MCLA-fed mice. Stearoyl-CoA desaturase activity in mammary tissue from TVA-fed dams was 14% greater compared with SA. Activity of this enzyme in liver tissue was similar among treatments. In pups nursing TVA-fed dams, 9/1 ICLA accounted for 3 mg x g(-1) in liver but no 9/11CLA was detected in the carcass. In pups nursing MCLA-fed dams, however, 9/11CLA accounted for 8 and 6 mg x g(-1) in liver and carcass. Results indicated TVA desaturation enhanced 9/11CLA in tissues and milk fat.
authors.affiliation: Dairy Science Department, Virginia Tech, Blacksburg 24061-0315, USA. jloor@uxl.cso.uiuc.edu
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Loor
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Lin
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Herbein
mesh_terms: D000284:Administration, Oral; D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000833:Animals, Suckling; D004041:Dietary Fats / Q000008:administration & dosage / Q000378:metabolism*; D005260:Female; D007536:Isomerism; D007774:Lactation / Q000378:metabolism*; D019787:Linoleic Acid / Q000096:biosynthesis*; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D008892:Milk / Q000737:chemistry*; D009829:Oleic Acids / Q000008:administration & dosage / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D004041:Dietary Fats; D009829:Oleic Acids; D019787:Linoleic Acid; C050413:11-octadecenoic acid