Fig. 3. GATA4 mediates the regulation of SASP induced by progerin.

a After the introduction of GFP-progerin, GATA4 expression was detected using western blot analysis. b Western blot analysis of GATA4 was conducted in progerin-overexpressing MSCs after the treatment with caffeine (5 mM) for 2 h. c Quantitative PCR analysis of MCP-1 in progerin-overexpressing MSCs in the presence of caffeine (5 mM) for 2 h. d hMSCs were cultured with CM from control or progerin-expressing hMSCs in the presence of caffeine. After 4 days of CM culture, the indicated cells were fixed and stained for the SA-β-gal activity. e Control and progerin-overexpressing hMSCs were treated with bafilomycin A1 (200 nM) or rapamycin (0.68 μM) for 7 h. The abundance of GATA4 protein was analyzed by western blotting. f Immunoblotting of GATA4 and GFP immunoprecipitates from control or progerin-expressing hMSCs. hMSCs were treated with bafilomycin A1 for 7 h before sampling to block GATA4 degradation. Error bars represent means ± s.d. from three separate experiments. Student’s t-test was used for the statistical analysis