Fig. 4. Dapa targets NHE1 hence regulating MAPK/AP-1 pathway to protect cardiomyocytes.
a Direct binding of Dapa and NHE1 protein was shown by SPR assay. Ka binding constant, Kd dissociation constant, KD equilibrium dissociation constant. b Molecular docking of Dapa with NHE1. c–h H9c2 cells were transfected with NHE1 siRNA or HA-NHE1 plasmid, and were then treated with Dapa and PA. Cell lysates from knockdown (c) or overexpression (d) assay were collected and proteins of p-ERK, p-JNK, and p-p38 were detected with total proteins as loading control. H9c2 cells after knockdown of NHE1 were stained with rhodamine-phalloidin (e) or TUNEL kit (f), and counterstained with DAPI. Representative images were shown. g, h H9c2 cells after overexpression of NHE1 were stained with TUNEL kit, and counterstained with DAPI (e, g, scale bar = 50 μm; f, h, scale bar = 100 μm). Representative images were shown. n = 3; Means ± SEM; One-way ANOVA followed by Turkey post-hoc tests.