Cardiomyocyte Contractility and Autophagy in a Premature Senescence Model of Cardiac Aging

Figure 2

Cellular senescence in cultured, neonatal cardiomyocytes. Assessed were discriminative biomarkers of cellular senescence in murine cardiac myocytes at indicated time points post primary cell isolation. Relative mRNA expressions of (a) Ki-67, (b) PCNA, and (c) p16 were quantified via qPCR analyses ( mice). (d) Protein levels of p53 were determined by immunoblot analyses normalized to GAPDH, and representative blots are illustrated ( mice). (e) The signal of immunofluorescently stained p21 in cardiomyocyte nuclei and (f) autofluorescence per cardiac myocytes were microscopically quantified ( mice). (g) As validated biomarker of cellular senescence, the SA-β-Gal activity at pH 6 was measured qualitatively as positively stained cardiomyocytes per total number of heart muscle cells ( mice). Data are presented as . Statistical significance was assessed by one-way ANOVA (); ^areference day 6; ^breference day 9; ^creference day 13; ^dreference day 17.

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