Influence of dietary conjugated linoleic Acid and fat source on body fat and apoptosis in mice.
OBJECTIVE
To determine whether altered dietary essential fatty acid (linoleic and arachidonic acid) concentrations alter sensitivity to conjugated linoleic acid (CLA)-induced body fat loss or DNA fragmentation.


METHODS
Mice were fed diets containing soy oil (control), coconut oil [essential fatty acid deficient (EFAD)], or fish oil (FO) for 42 days, and then diets were supplemented with a mixture of CLA isomers (0.5% of the diet) for 14 days. Body fat index, fat pad and liver weights, DNA fragmentation in adipose tissue, and fatty acid profiles of adipose tissue were determined.


RESULTS
The EFAD diet decreased (p < 0.05) linoleic and arachidonic acid in mouse adipose tissue but did not affect body fat. Dietary CLA caused a reduction (p < 0.05) in body fat. Mice fed the EFAD diet and then supplemented with CLA exhibited a greater reduction (p < 0.001) in body fat (20.21% vs. 6.94% in EFAD and EFAD + CLA-fed mice, respectively) compared with mice fed soy oil. Dietary FO decreased linoleic acid and increased arachidonic acid in mouse adipose tissue. Mice fed FO or CLA were leaner (p < 0.05) than control mice. FO + CLA-fed mice did not differ in body fat compared with FO-fed mice. Adipose tissue apoptosis was increased (p < 0.001) in CLA-supplemented mice and was not affected by fat source.


CONCLUSIONS
Reductions in linoleic acid concentration made mice more sensitive to CLA-induced body fat loss only when arachidonic acid concentrations were also reduced. Dietary essential fatty acids did not affect CLA-induced DNA fragmentation.
Department of Animal Science, University of Nebraska, C220 ANS, Lincoln, NE 68583, USA.
Kimberly M
KM
Hargrave
Brett J
BJ
Meyer
Changlong
C
Li
Michael J
MJ
Azain
Clifton A
CA
Baile
Jess L
JL
Miner
D000273:Adipose Tissue / Q000737:chemistry / Q000166:cytology; D000818:Animals; D017209:Apoptosis; D016718:Arachidonic Acid / Q000032:analysis; D001823:Body Composition; D000074263:Coconut Oil; D053938:DNA Fragmentation; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D005228:Fatty Acids, Essential / Q000172:deficiency; D005395:Fish Oils / Q000008:administration & dosage; D019787:Linoleic Acid / Q000032:analysis; D044243:Linoleic Acids, Conjugated / Q000008:administration & dosage*; D008099:Liver / Q000033:anatomy & histology; D051379:Mice; D009929:Organ Size; D010938:Plant Oils / Q000008:administration & dosage; D013024:Soybean Oil / Q000008:administration & dosage
D004042:Dietary Fats, Unsaturated; D005228:Fatty Acids, Essential; D005395:Fish Oils; D044243:Linoleic Acids, Conjugated; D010938:Plant Oils; D016718:Arachidonic Acid; D013024:Soybean Oil; D019787:Linoleic Acid; D000074263:Coconut Oil