Puerarin inhibits NHE1 activity by interfering with the p38 pathway and attenuates mitochondrial damage induced by myocardial calcium overload in heart failure rats

Figure 1 Pue prevented the progression of myocardial fibrosis and improved left ventricular function in ADR-induced HF rats (A) HE staining. (B) Normal cardiomyocyte ratio of HE-stained cells. (C) Gomori silver staining. (D) Quantitative analysis of the reticular fiber area in the myocardial tissue of each group. (E) Masson staining. (F) Quantitative analysis of collagen fiber area in each group. (G,I) Representative two-dimensional and M-mode short-axis echocardiographic images of left ventricular function. (H,J) Quantitative analysis of echocardiography parameters (EF% and SV) in each group. Data were analyzed by using one-way ANOVA. All data are expressed as the mean±SEM (n=5 for B,D,F; n=6 for panels H,J). *P<0.05 vs the Con group; #P<0.05 vs the ADR group.

Figure 2 Pue reduced intracellular free sodium and calcium ion concentrations and attenuated mitochondrial damage caused by calcium overload Representative immunofluorescence images of [Na+]i (A) and [Ca2+]i (C) in single ventricular heart cells of each group. (B) Quantitation of cytoplasmic Na+ fluorescence. (D) Quantitation of cytoplasmic Ca2+ fluorescence. (E) Mitochondrial transmission electron microscopy. (F) Quantitative analysis of mitochondrial structure. Data are presented as the mean±SEM. *P<0.05 vs the Con group; #P<0.05 vs the ADR group, one-way ANOVA (n=4 for panels A,C; n=6 for E).

Figure 3 Effects of Pue on NHE1 expression in myocardial tissue of ADR-induced HF rats (A) Overall effect diagram of Pue and NHE 1 docking. (B) Immunohistochemistry images of NHE1 in myocardial tissues of each group. (C) Quantitative data of the positive expression of NHE1. (D) Representative western blots of NHE1 expression. (E) Statistical analysis of the protein expression of NHE1. Data are presented as the mean±SEM. *P<0.05 vs the Con group; #P<0.05 vs the ADR group, one-way ANOVA (n=5 for panel B; n=4 for D).

Figure 4 Pue inhibited p38 activation and reduced cardiac fibrosis and proinflammatory cytokine production in the myocardial tissue of ADR-induced HF rats (A) The mRNA levels of IL-Iβ, IL-6, TNF-αand TGF-β in the myocardial tissue of each group. (B) Representative western blots of p-p38 expression. (C) Statistical analysis of the ratio of p-p38/p38. (D) Immunofluorescence staining of p-p38 in myocardial tissues of each group. (E) Quantitative analysis of p-p38. Data are presented as the mean±SEM. *P<0.05 vs the Con group; #P<0.05 vs the ADR group, one-way ANOVA (n=4).