| First Author | Akasaka Y | Year | 2010 |
| Journal | Biochim Biophys Acta | Volume | 1801 |
| Issue | 10 | Pages | 1115-22 |
| PubMed ID | 20601111 | Mgi Jnum | J:165456 |
| Mgi Id | MGI:4837322 | Doi | 10.1016/j.bbalip.2010.06.009 |
| Citation | Akasaka Y, et al. (2010) Direct evidence for leptin-induced lipid oxidation independent of long-form leptin receptor. Biochim Biophys Acta 1801(10):1115-22 |
| abstractText | Leptin administration has been shown to enhance muscle lipid oxidation in relation to the energy expenditure. Both long-form (Ob-R(L)) and short-form leptin receptors (Ob-R(S)) are expressed in skeletal muscle, but the role of Ob-R(S) is unclear. In the present study, the role of Ob-R(S) in leptin-induced lipid oxidation in skeletal muscles was investigated using primary murine myotubes from m/m and db/db mice. Primary myotubes were treated with leptin (0.1, 1, 10, 100nM) for 24h. Lipid oxidation was determined by (14)CO(2) production rate from [1-(14)C] palmitate. Leptin was found to increase lipid oxidation in a dose- and time-dependent manner in db/db myotubes as well as in m/m myotubes. Leptin significantly increased phosphorylation of JAK2 and STAT3 in both types of myotube. Leptin-induced lipid oxidation was abolished by STAT3 siRNA. To investigate the mechanism underlying leptin-induced lipid oxidation, the effects of pharmacological inhibitors were examined. JAK2 or p38 MAPK inhibitor suppressed leptin-induced lipid oxidation and decreased STAT3 phosphorylation in both types of myotube, respectively. Leptin significantly increased phosphorylation of p38 MAPK, and leptin-induced lipid oxidation was abolished by treatment with p38 MAPK siRNA in both types of myotube. These results suggest that leptin induces lipid oxidation in skeletal muscle through the JAK2/p38 MAPK/STAT3 signaling pathway via not only Ob-R(L) but also Ob-R(S). |
