|
|
||||||||
HORMONES AND SIGNALING
Department of Human Nutrition, The Ohio State University, Columbus, Ohio
Submitted 9 November 2006 ; accepted in final form 16 February 2007
Dysfunctional cross talk between adipose tissue and liver tissue results in metabolic and inflammatory disorders. As an insulin sensitizer, rosiglitazone (Rosi) improves insulin resistance yet causes increased adipose mass and weight gain in mice and humans. Conjugated linoleic acid (CLA) reduces adipose mass and body weight gain but induces hepatic steatosis in mice. We examined the combined effects of Rosi and CLA on adiposity, insulin sensitivity, and hepatic steatosis in high-fat-fed male C57Bl/6 mice. CLA alone suppressed weight gain and adipose mass but caused hepatic steatosis. Addition of Rosi attenuated CLA-induced insulin resistance and dysregulation of adipocytokines. In adipose, CLA significantly suppressed lipoprotein lipase and fatty acid translocase (FAT/CD36) mRNA, suggesting inhibition of fatty acid uptake into adipose; addition of Rosi completely rescued this effect. In addition, CLA alone increased markers of macrophage infiltration, F4/80, and CD68 mRNA levels, without inducing TNF-
in epididymal adipose tissue. The ratio of Bax to Bcl2, a marker of apoptosis, was significantly increased in adipose of the CLA-alone group and was partially prevented by treatment of Rosi. Immunohistochemistry of F4/80 demonstrates a proinflammatory response induced by CLA in epididymal adipose. In the liver, CLA alone induced microsteatotic liver but surprisingly increased the rate of very-low-density lipoprotein-triglyceride production without inducing inflammatory mediator-TNF-
and markers of macrophage infiltration. These changes were accompanied by significantly increased mRNA levels of stearoyl-CoA desaturase, FAT/CD36, and fatty acid synthase. The combined administration of CLA and Rosi reduced hepatic liver triglyceride content as well as lipogenic gene expression compared with CLA alone. In summary, dietary CLA prevented weight gain in Rosi-treated mice without attenuating the beneficial effects of Rosi on insulin sensitivity. Rosi ameliorated CLA-induced lipodystrophic disorders that occurred in parallel with rescued expression of adipocytokine and adipocytes-abundant genes.
This article has been cited by other articles:
![]() |
L. E Norris, A. L Collene, M. L Asp, J. C Hsu, L.-F. Liu, J. R Richardson, D. Li, D. Bell, K. Osei, R. D Jackson, et al. Comparison of dietary conjugated linoleic acid with safflower oil on body composition in obese postmenopausal women with type 2 diabetes mellitus Am. J. Clinical Nutrition, September 1, 2009; 90(3): 468 - 476. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Kennedy, S. Chung, K. LaPoint, O. Fabiyi, and M. K. McIntosh Trans-10, Cis-12 Conjugated Linoleic Acid Antagonizes Ligand-Dependent PPAR{gamma} Activity in Primary Cultures of Human Adipocytes J. Nutr., March 1, 2008; 138(3): 455 - 461. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. Cave, R. T. Hurt, T. H. Frazier, P. J. Matheson, R. N. Garrison, C. J. McClain, and S. A. McClave Obesity, Inflammation, and the Potential Application of Pharmaconutrition Nutr Clin Pract, February 1, 2008; 23(1): 16 - 34. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |