P16^INK4a Regulates ROS-Related Autophagy and CDK4/6-Mediated Proliferation: A New Target of Myocardial Regeneration Therapy

Figure 4

Overexpression p16^INK4a inhibits myocardial regeneration and repair after AR in neonatal mice. (a, b) Western blot and qRT-PCR were used to detect the expression of p16^INK4a in ventricular muscle after specific overexpression of p16^INK4a at 6 dpr (). (c, d) The proliferation proportion of cardiomyocytes in the heart at 6 dpr was counted by Ki67 and pH 3 immunofluorescence after myocardial injection of NC or INK4a in neonatal mice (). Scale bar: 20 μm, 50 μm. (e) Cardiac function was detected by echocardiography at 1 dpr and 28 dpr after AR (). (f) Comparison of scar size by Masson staining between the NC and INK4a groups at 28 days after AR (). Scale bar: 50 μm, 500 μm. (g) Overall survival rate of neonatal mice in the P1-P28 stage after myocardial injection in situ of NC or INK4a after AR () (data are presented as ; NS: no statistical difference, , , ).

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