| First Author | Li G | Year | 2015 |
| Journal | PLoS One | Volume | 10 |
| Issue | 4 | Pages | e0122593 |
| PubMed ID | 25923694 | Mgi Jnum | J:235099 |
| Mgi Id | MGI:5792779 | Doi | 10.1371/journal.pone.0122593 |
| Citation | Li G, et al. (2015) PPARalpha Protein Expression Was Increased by Four Weeks of Intermittent Hypoxic Training via AMPKalpha2-Dependent Manner in Mouse Skeletal Muscle. PLoS One 10(4):e0122593 |
| abstractText | Peroxisome proliferator-activated receptor alpha (PPARalpha) is critical for muscle endurance due to its role in the regulation of fatty acid oxidation. The 5'-AMP-activated protein kinase (AMPK) is an energy sensor in cells, but its role in PPARalpha regulation in vivo remains unknown. In this study, we examined PPARalpha expression in the skeletal muscle of AMPKalpha2 overexpression (OE), knockout (KO) and wild-type (WT) mice after four weeks of exercise under intermittent hypoxia. WT, OE and KO mice were used at 40 mice/strain and randomly subdivided into four subgroups: control (C), running (R), hypoxia (H), and running plus hypoxia (R+H) at 10 mice/group. The treadmill running was performed at the speed of 12 m/min, 60 min/day with a slope of 0 degree for four weeks. The hypoxia treatment was performed in daytime with normobaric hypoxia (11.20% oxygen, 8 hours/day). In the R+H group, the treadmill running was conducted in the hypoxic condition. AMPKalpha2, phosphor-AMPKalpha (p-AMPKalpha) (Thr172), nuclear PPARalpha proteins were measured by Western blot and the medium chain acyl coenzyme A dehydrogenase (MCAD) mRNA, the key enzyme for fatty acid oxidation and one of the PPARalpha target genes, was also measured in skeletal muscles after the interventions. The results showed that nuclear PPARalpha protein was significantly increased by R+H in WT muscles, the increase was enhanced by 41% (p<0.01) in OE mice, but was reduced by 33% (p<0.01) in KO mice. The MCAD mRNA expression was increased after four weeks of R+H intervention. The change in MCAD mRNA followed a similar trend as that of PPARalpha protein in OE and KO mice. Our data suggest that the increase in nuclear PPARalpha protein by four-week exercise training under the intermittent hypoxia was dependent on AMPK activation. |
