Fig. 3
Protein expression of SGLT1, and activation of ERK1/2 and AMPKα. a Relative protein expression of left ventricular (LV) sodium-glucose cotransporter 1 (SGLT1) in controls and in patients with heart failure (HF). A representative blot is shown. b The ratio of LV phosphorylated extracellular signal-regulated kinase 1/2 (P-ERK1/2) versus total ERK1/2 (t-ERK1/2) in controls and in patients with HF. A representative blot is shown. c The ratio of LV phosphorylated adenosine-monophosphate-activated protein kinase α catalytic subunit (P-AMPKα) versus total AMPKα (t-AMPKα) in controls and in patients with HF. A representative blot is shown. d Correlation between LV end-diastolic diameter (LVEDD), ejection fraction (EF) and SGLT1 relative protein expression. e Correlation between LVEDD, EF and P-ERK1/2 / t-ERK1/2 relative protein expression. f Correlation between LVEDD, EF and P-AMPKα / t- AMPKα relative protein expression. g Correlation between P-ERK1/2 / t-ERK1/2 and SGLT1 relative protein expressions. h Correlation between P- AMPKα / t-AMPKα and SGLT1 relative protein expressions. For easier interpretation, expression values are normalized to that of Controls (i.e. mean of Control group = 1.00). To compare means of five groups, one-way analysis of variance (ANOVA) was performed with Welch’s correction followed by Dunnett T3 post hoc test to compute intergroup differences relative to the Control group. Statistical significance according to the post hoc test (relative to Control) is highlighted as follows: *P < 0.05, **P < 0.01. For zero-order correlation analysis, Spearman’s rho (rs) was computed. For all correlation coefficients, bias-corrected and accelerated (BCa) 95% confidence intervals (CI) are reported based on n = 1000 bootstrap samples. AMPKα adenosine-monophosphate-activated protein kinase α catalytic subunit, DCM dilated cardiomyopathy, EF ejection fraction, ERK1/2 extracellular signal-regulated kinase 1/2, f. c. fold change, HCM hypertrophic cardiomyopathy, LVEDD left ventricular end-diastolic diameter, IHD ischemic heart disease, IHD-T2DM IHD and type 2 diabetes mellitus, rs Spearman’s rho (correlation coefficient), SGLT1 sodium-glucose cotransporter 1