Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: The contrasting roles of PPARδ and PPARg in regulating the metabolic switch between oxidation and storage of fats in white adipose tissue. | Roberts et al. Genome Biology 2011 12 R75 http 2011 12 8 R75 Genome Biology RESEARCH Open Access The contrasting roles of PPARỖ and PPARg in regulating the metabolic switch between oxidation and storage of fats in white adipose tissue 3 3 1 4 Lee D Roberts 1 Andrew J Murray David Menassa Tom Ashmore Andrew W Nicholls and Julian L Griffin1 2 5 6 Abstract Background The nuclear receptors peroxisome proliferator-activated receptor g PPARg and peroxisome proliferator-activated receptor ỗ PPARS play central roles in regulating metabolism in adipose tissue as well as being targets for the treatment of insulin resistance. While the role of PPARg in regulating insulin sensitivity has been well defined research into PPARỖ has been limited until recently due to a scarcity of selective PPARỖ agonists. Results The metabolic effects of PPARg and PPARỖ activation have been examined in vivo in white adipose tissue from ob ob mice and in vitro in cultured 3T3-L1 adipocytes using 1H nuclear magnetic resonance spectroscopy and mass spectrometry metabolomics to understand the receptors contrasting roles. These steady state measurements were supplemented with 13C-stable isotope substrate labeling to assess fluxes in addition to respirometry and transcriptomic microarray analysis. The metabolic effects of the receptors were readily distinguished with PPARg activation characterized by increased fat storage synthesis and elongation while PPARỖ activation caused increased fatty acid p-oxidation tricarboxylic acid cycle rate and oxidation of extracellular branch chain amino acids. Stimulated glycolysis and increased fatty acid desaturation were common pathways for the agonists. Conclusions PPARg and PPARỖ restore insulin sensitivity through varying mechanisms. PPARỖ activation increases total oxidative metabolism in white adipose tissue a tissue not traditionally thought of as oxidative. However the increased metabolism of branch chain amino acids may provide a .
