First Author | Suzuki J | Year | 2001 |
Journal | Am J Physiol Endocrinol Metab | Volume | 281 |
Issue | 4 | Pages | E857-66 |
PubMed ID | 11551864 | Mgi Jnum | J:72103 |
Mgi Id | MGI:2151731 | Doi | 10.1152/ajpendo.2001.281.4.E857 |
Citation | Suzuki J, et al. (2001) Absence of cardiac lipid accumulation in transgenic mice with heart-specific HSL overexpression. Am J Physiol Endocrinol Metab 281(4):E857-66 |
abstractText | Hormone-sensitive lipase (HSL) hydrolyzes triglyceride (TG) in adipose tissue. HSL is also expressed in heart. To explore the actions of cardiac HSL, heart-specific, tetracycline (Tc)-controlled HSL-overexpressing mice were generated. Tc-responsive element-HSL transgenic (Tg) mice were generated and crossed with myosin heavy chain (MHC)alpha-tTA Tg mice, which express the Tc-responsive transactivator (tTA) in the heart. The double-Tg mice (MHC-HSL) were maintained with doxycycline (Dox) to suppress Tg HSL. Upon removal of Dox, cardiac HSL activity and protein increased 12- and 8-fold, respectively, and the expression was heart specific. Although cardiac TG content increased twofold in control mice after an overnight fast, it did not increase in HSL-induced mice. Electron microscopy showed numerous lipid droplets in the myocardium of fasted control mice, whereas fasted HSL-induced mice showed virtually no droplets. Microarray analysis showed altered expression of cardiac genes for fatty acid oxidation, transcription factors, signaling molecules, cytoskeletal proteins, and histocompatibility antigens in HSL-induced mice. Thus cardiac HSL plays a role in controlling accumulation of triglyceride droplets and can affect the expression of a number of cardiac genes. |