Figure 1. Confocal analysis of SIRT1 localization in the heart of wild type and mIGF-1 transgenic mice.
(A) representative heart sections of a 3 months old wild type (WT, upper panel) and of a cardiac restricted mIGF-1 transgenic mouse (mIGF-1, lower panel), stained for cardiomyocyte specific marker sarcomeric myosin (red), SIRT1 (green). Nuclei are counterstained with DAPI (blue). (B) quantification of SIRT1 positive nuclei, as shown in A. Total DAPI positive nuclei considered for quantification of SIRT1 immunopositivity in WT = 2280, and in mIGF-1 Tg = 2053, in 4 independent preparations. (C) representative heart sections of a 3 months old WT (upper panel) and of a cardiac restricted mIGF-1 Tg mouse (lower panel), stained for vimentin (red), SIRT1 (green). Nuclei are counterstained with DAPI (blue). Mesenchymal cells cytoplasm (arrows) appeared positive for both vimentin (red) and SIRT1 (green). Whereas in other cell types, presumably cardiomyocytes due to nuclear localization of SIRT1 (green), vimentin is lacking in thecytoplasm (arrowheads). Scale Bars= 10 μm.