Pterostilbene Attenuates Fructose-Induced Myocardial Fibrosis by Inhibiting ROS-Driven Pitx2c/miR-15b Pathway

Figure 5

Pterostilbene and allopurinol increase miR-15b expression to suppress p-p53-dependent TGF-β1/Smads signaling activation in fructose-exposed H9c2 cells. Cellular levels of p-p53 protein (a) and miR-15b expression (b) were determined in p53 siRNA-transfected H9c2 cells coincubated with 5 mM fructose, 10 μM pterostilbene, and 30 μM allopurinol (). The relative miR-15b expression levels were normalized to U6. Cellular p-p53 protein levels were determined in miR-15b mimic (c) or miR-15b inhibitor (d)-transfected H9c2 cells coincubated with 5 mM fructose, 10 μM pterostilbene, and 30 μM allopurinol, respectively. Protein levels of TGF-β1, p-Smad2/3, and Smad4 were determined in these cells ((e–h) miR-15b mimic; (i–l) miR-15b inhibitor) (), respectively. Relative protein levels of p-p53 were normalized to p53, of TGF-β1 and Smad4 were normalized to GAPDH, and of p-Smad2/3 were normalized to Smad2/3, respectively. Data are expressed as the ^#, ^##, and ^### vs. normal cell control group; , , and vs. fructose-vehicle cell group or fructose-vehicle+p53 siRNA or miR-15b mimic or miR-15b inhibitor control cell group.

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