Moderate-Dose Exercise Protects Against Heart Failure via Apelin/NLRP3 Mediated Inflammation

Figures

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  Fig. 1.. Exercise increases cardiac function in mice with HF. (A) Exercise training protocol initiated 2 weeks after MI surgery. (B) Representative echocardiographic images of M-mode in mice of different groups after 8 weeks of exercise training. (C) Heart rate. (D) Left ventricular ejection fraction (LVEF). (E) Left ventricular fractional shortening (LVFS). (F) Left ventricular internal dimension at end-diastole (LVIDd) and (G) at end-systole (LVIDs). (H) Left ventricular stroke volume (LVSV). (I) Heart weight to tibia length ratio (HW/TL). **p < 0.01 compared with sham group; #p < 0.05, ##p < 0.01 compared with MI group; ††p < 0.01 compared with Ex30 group; One-way ANOVA followed by Tukey’s post hoc test. All data are mean ± standard deviation (SD). HF, heart failure; MI, myocardial infarction; ns, not significant.

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  Fig. 2.. Moderate-dose exercise alleviates ventricular remodeling in mice with HF. (A) Gross morphological changes of hearts after 8-week swimming training. (B) Representative HE-stained cardiac sections of different groups, Scale bars: 50 μm. (C,D) Representative sections for cardiomyocyte area (WGA-stained) and its mean data, Scale bars: 50 μm. (E,G) Interstitial fibrosis (Picrosirius red-stained) and its mean data, Scale bars: 100 μm. (F,H) Masson’s trichrome staining and its mean data, Scale bars: 50 μm. (I,J) Protein levels of α-SMA in hearts of mice from different groups and its mean data of protein immunoblots, n = 3/group. **p < 0.01 compared with sham group; #p < 0.05, ##p < 0.01 compared with MI group; †p < 0.05 compared with Ex30 group; One-way ANOVA followed by Tukey’s post hoc test. All data are mean ± SD. α-SMA, alpha-smooth muscle actin; HF, heart failure; ns, not significant; WGA, wheat germ agglutinin.

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  Fig. 3.. HF biomarkers were decreased in HF mice treated with moderate-dose exercise. (A) Immunohistochemical analysis of BNP and ANP with the heart tissues in HF mice from different groups, Scale bars: 50 μm. (B,C) Quantitation of BNP and ANP positive staining, n = 3/group. **p < 0.01 compared with sham group; #p < 0.05, ##p < 0.01 compared with MI group; †p < 0.05, ††p < 0.01 compared with Ex30 group; One-way ANOVA followed by Tukey’s post hoc test. All data are mean ± SD. ANP, atrial natriuretic peptide; BNP, B‑type natriuretic peptide; ns, not significant.

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  Fig. 4.. Moderate-dose exercise increases the collateral circulation in the infarction areas of the heart in HF mice. (A,B) Immunofluorescence staining to visualize the localization of CD31 and VEGFA in the myocardial infarction (MI) border zone of mouse hearts from different groups. Scale bars: 50 μm (white bars), 100 μm (red bars). CD31, Cluster of Differentiation 31; VEGFA, Vascular Endothelial Growth Factor A.

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  Fig. 5.. Moderate-dose exercise modulates lipid metabolism via Apelin pathway. (A,B) KEGG pathway enrichment analysis of differential molecules was performed for the sham vs. MI (A) and MI vs. moderate-dose exercise group (B) comparisons, respectively, showing the number of altered molecules within three core pathways at both the metabolome and transcriptome levels. (C,D) Bar charts display the p-values of KEGG enrichment for three core pathways at the metabolome and transcriptome levels in the sham vs. MI (C) and MI vs. moderate-dose exercise group (D) comparisons, respectively. (E,F) Protein levels of Apelin in the hearts of mice from different groups and their mean data of protein immunoblots, n = 3/group. **p < 0.01 compared with sham group; #p < 0.05 compared with MI group; One-way ANOVA followed by Tukey’s post hoc test. All data are mean ± standard deviation (SD).

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  Fig. 6.. Moderate-dose exercise modulates lipid metabolism and inflammation in mice with HF. (A) Heatmap of intra-group sample correlation analysis results. Colored bars from yellow to red represent the correlation coefficient from low to high. A correlation coefficient closer to 1 indicates higher similarity in expression patterns between samples. (B) Volcano plot analysis of 1840 DEGs between the 2 groups. Each dot represents a gene detected in both groups. Red and blue dots indicate genes with significantly upregulated and downregulated expression, respectively. Black dots represent genes that did not show significant differential expression between the MI vs Ex30 (filter criteria: FDR <0.05, |log2FC| >1). (C,D) The horizontal axis of the bubble plot represents the Rich Factor. Bubble plots show the KEGG pathway enrichment of down-regulated genes in the sham vs. MI group (D) comparison of up-regulated genes in the MI vs. moderate-dose exercise group (C), respectively; larger bubbles indicate a greater number of genes. Additionally, the color of the bubbles represents the significance of enrichment, measured by the Q-value, which is a p-value adjusted for FDR. DEGs, differentially…

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  Fig. 7.. Moderate-dose exercise suppresses inflammation in HF mice via the Nrf2 pathway. (A,B) Immunofluorescence staining of NLRP3 in the hearts of mice and quantitation of its positive staining. (C,D) Immunofluorescence staining of IL-1β in the hearts of mice and quantitation of its positive staining. Scale bars: 50 μm; n = 3/group. (E–G) Protein levels of NLRP3 and IL-1β in hearts of mice from different groups and their mean data of protein immunoblots, n = 3/group. (H–J) Protein levels of Nrf2 and HO-1 in the hearts of mice from different groups and their mean data of protein immunoblots, n = 3/group. **p < 0.01 compared with sham group; #p < 0.05, ##p < 0.01 compared with the MI group; One-way ANOVA followed by Tukey’s post hoc test. All data are mean ± SD. Nrf2, Nuclear factor erythroid 2-related factor 2; NLRP3, NOD-like receptor pyrin domain-containing 3; IL-1β, interleukin 1-beta; HO-1, heme oxygenase-1.