| First Author | Habets DD | Year | 2009 |
| Journal | Biochim Biophys Acta | Volume | 1791 |
| Issue | 3 | Pages | 212-9 |
| PubMed ID | 19159696 | Mgi Jnum | J:148739 |
| Mgi Id | MGI:3846293 | Doi | 10.1016/j.bbalip.2008.12.009 |
| Citation | Habets DD, et al. (2009) Crucial role for LKB1 to AMPKalpha2 axis in the regulation of CD36-mediated long-chain fatty acid uptake into cardiomyocytes. Biochim Biophys Acta 1791(3):212-9 |
| abstractText | Enhanced contractile activity increases cardiac long-chain fatty acid (LCFA) uptake via translocation of CD36 to the sarcolemma, similarly to increase in glucose uptake via GLUT4 translocation. AMP-activated protein kinase (AMPK) is assumed to mediate contraction-induced LCFA utilization. However, which catalytic isoform (AMPKalpha1 versus AMPKalpha2) is involved, is unknown. Furthermore, no studies have been performed on the role of LKB1, a kinase with AMPKK activity, on the regulation of cardiac LCFA utilization. Using different mouse models (AMPKalpha2-kinase-dead, AMPKalpha2-knockout and LKB1-knockout mice), we tested whether LKB1 and/or AMPK are required for stimulation of LCFA and glucose utilization upon treatment of cardiomyocytes with compounds (oligomycin/AICAR/dipyridamole) which induce CD36 translocation similar to that seen upon contraction. In AMPKalpha2- kinase-dead cardiomyocytes, the stimulating effects of oligomycin and AICAR on palmitate and deoxyglucose uptake and palmitate oxidation were almost completely lost. Moreover, in AMPKalpha2- and LKB1-knockout cardiomyocytes, oligomycin-induced LCFA and deoxyglucose uptake were completely abolished. However, the stimulatory effect of dipyridamole on palmitate uptake and oxidation was preserved in AMPKalpha2-kinase-dead cardiomyocytes. In conclusion, in the heart there is a signaling axis consisting of LKB1 and AMPKalpha2 which activation results in enhanced LCFA utilization, similarly to enhanced glucose uptake. In addition, an unknown dipyridamole-activated pathway can stimulate cardiac LCFA utilization by activating signaling components downstream of AMPK. |
