02437nas a2200325 4500008004100000245014100041210006900182260001400251300001400265490000800279520142200287100002001709700001501729700002101744700003101765700002001796700002001816700002001836700002001856700001901876700002101895700002001916700002301936700001901959700002201978700002602000700001802026700001802044856004902062 2008 eng d00aOverexpression of vascular endothelial growth factor-B in mouse heart alters cardiac lipid metabolism and induces myocardial hypertrophy0 aOverexpression of vascular endothelial growth factorB in mouse h c2008/Oct/ a1018 - 260 v1033 aVascular endothelial growth factor (VEGF)-B is poorly angiogenic but prominently expressed in metabolically highly active tissues, including the heart. We produced mice expressing a cardiac-specific VEGF-B transgene via the alpha-myosin heavy chain promoter. Surprisingly, the hearts of the VEGF-B transgenic mice showed concentric cardiac hypertrophy without significant changes in heart function. The cardiac hypertrophy was attributable to an increased size of the cardiomyocytes. Blood capillary size was increased, whereas the number of blood vessels per cell nucleus remained unchanged. Despite the cardiac hypertrophy, the transgenic mice had lower heart rate and blood pressure than their littermates, and they responded similarly to angiotensin II-induced hypertension, confirming that the hypertrophy does not compromise heart function. Interestingly, the isolated transgenic hearts had less cardiomyocyte damage after ischemia. Significantly increased ceramide and decreased triglyceride levels were found in the transgenic hearts. This was associated with structural changes and eventual lysis of mitochondria, resulting in accumulation of intracellular vacuoles in cardiomyocytes and increased death of the transgenic mice, apparently because of mitochondrial lipotoxicity in the heart. These results suggest that VEGF-B regulates lipid metabolism, an unexpected function for an angiogenic growth factor.1 aKarpanen, Terhi1 aBry, Maija1 aOllila, Hanna, M1 aSeppänen-Laakso, Tuulikki1 aLiimatta, Erkki1 aLeskinen, Hanna1 aKivelä, Riikka1 aHelkamaa, Teemu1 aMerentie, Mari1 aJeltsch, Michael1 aPaavonen, Karri1 aAndersson, Leif, C1 aMervaala, Eero1 aHassinen, Ilmo, E1 aYlä-Herttuala, Seppo1 aOresic, Matej1 aAlitalo, Kari uhttp://view.ncbi.nlm.nih.gov/pubmed/18757827