Pathways affected by 3,5-diiodo-l-thyronine in liver of high fat-fed rats: evidence from two-dimensional electrophoresis, blue-native PAGE, and mass spectrometry.
3,5-Diiodo-l-thyronine (T2) powerfully reduces adiposity in rats fed a high-fat diet (HFD), stimulating (in the liver) fatty acid oxidation and mitochondrial uncoupling, and strongly counteracting steatosis, a condition commonly associated with diet-induced obesity. Proteomics offer unique possibilities for the investigation of changes in the levels and modifications of proteins. Here, combining 2D-E, mass spectrometry, and blue native (BN) PAGE, we studied how the subcellular hepatic phenotype responds to HFD and T2-treatment. By identifying differentially expressed proteins and analyzing their interrelation [using the Ingenuity Pathway Analysis (IPA) platform], we obtained an integrated view of the phenotypic/metabolic adaptations occurring in the liver proteome during HFD with or without T2-treatment. Interestingly, T2 counteracted several HFD-induced changes, mostly in mitochondria. BN-PAGE and subsequent in-gel activity analysis of OXPHOS complexes revealed a modified profile of individual complexes in HFD mitochondria vs. normal ones. This pattern was re-normalized in mitochondria from T2-treated HFD animals. These data indicate that in HFD rats, the effects of T2 on the liver proteome cause it to resemble that associated with a non-steatotic condition. The identified metabolic pathways (mainly at the mitochondrial level) may be responsible for the beneficial effects of T2 on liver adiposity and metabolism.
Silvestri
Elena
E
Dipartimento di Scienze Biologiche ed Ambientali, Università degli Studi del Sannio, Via Port'Arsa 11, 82100 Benevento, Italy.
Cioffi
Federica
F
Glinni
Daniela
D
Ceccarelli
Michele
M
Lombardi
Assunta
A
de Lange
Pieter
P
Chambery
Angela
A
Severino
Valeria
V
Lanni
Antonia
A
Goglia
Fernando
F
Moreno
Maria
M
D000818:Animals; D019295:Computational Biology; D003593:Cytoplasm / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage* / Q000494:pharmacology*; D004104:Diiodothyronines / Q000008:administration & dosage / Q000494:pharmacology*; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D005247:Feeding Behavior / Q000187:drug effects; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D040901:Proteomics; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013194:Staining and Labeling; D014280:Triglycerides / Q000378:metabolism
D004041:Dietary Fats; D004104:Diiodothyronines; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; D014280:Triglycerides; C030103:3,5-diiodothyronine