| Full text | |
| Author(s): Show less - |
Christoffolete, Marcelo Augusto
;
Silva, William Jose
;
Ramos, Gracielle Vieira
;
Bento, Mirella Ribeiro
;
Costa, Monique Oliveira
;
Ribeiro, Miriam Oliveira
;
Okamoto, Maristela Mitiko
;
Lohmann, Tania Helena
;
Machado, Ubiratan Fabres
;
Musaro, Antonio
;
Moriscot, Anselmo Sigari
Total Authors: 11
|
| Document type: | Journal article |
| Source: | BIOMED RESEARCH INTERNATIONAL; v. 2015, p. 8-pg., 2015-01-01. |
| Abstract | |
We characterized the metabolic profile of transgenic mice exhibiting enhanced muscle mass driven by increased mIGF-1 expression (MLC/mIGF-1). As expected, 6-month-old MLC/mIGF-1 mice were heavier than age-matched wild type (WT) mice (37.4 +/- 0.3 versus 31.8 +/- 0.6 g, resp.). MLC/mIGF-1 mice had higher respiratory quotient when compared to WT (0.9 +/- 0.03 versus 0.74 +/- 0.02, resp.) suggesting a preference for carbohydrate as the major fuel source. MLC/mIGF-1 mice had a higher rate of glucose disposal when compared to WT (3.25 +/- 0.14 versus 2.39 +/- 0.03%/min, resp.). The higher disposal rate correlated to similar to 2-fold higher GLUT4 content in the extensor digitorum longus (EDL) muscle. Analysis of mRNA content for the glycolysis-related gene PFK-1 showed similar to 3-fold upregulation in MLC/mIGF-1 animals. We also found a 50% downregulation of PGC1 alpha mRNA levels in MLC/mIGF-1 mouse EDL muscle, suggesting less abundant mitochondria in this tissue. We found no difference in the expression of PPAR alpha and PPAR beta/delta, suggesting no modulation of key elements in oxidative metabolism. These data together suggest a shift in metabolism towards higher carbohydrate utilization, and that could explain the increased insulin sensitivity of hypertrophied skeletal muscle in MLC/mIGF-1 mice. (AU) | |
| FAPESP's process: | 12/22488-2 - Expression of microRNAs in the skeletal muscle plasticity: the possible interrelationships with MuRFs effect in the regenerative process |
| Grantee: | William Jose da Silva |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |