Metabolic Profiling Identifies 1-MetHis and 3-IPA as Potential Diagnostic Biomarkers for Patients With Acute and Chronic Heart Failure With Reduced Ejection Fraction

Figures

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  Figure 1.. Overview of differences in metabolomics parameters between different groups of patients. A, Acylcarnitines (ACs). B, Fatty acids (FAs). C, Diacyglycerols (DGs). D, Triglycerides (TGs). E, Cholesteryl ester (CE). F, Phosphatidylcholines (PCs). G, Sphingomyelins (SMs). H, Carboxylic acids (CAs). I, Amino acid related (AR). J, Amino acids (AAs). K, Biogenic amines (BAs). L, Bile acid (BL). Each value of the specific metabolite species within a metabolic group was added for every patient. Each point represents 1 patient of the respective patient cohort. Metabolite concentration is shown for patients with acute decompensated heart failure (ADHF), chronic heart failure (CHF), dilated cardiomyopathy (DCM), and ischemic cardiomyopathy (ICM) as a boxplot overlapped with a dot plot. The box represents the 25th to 75th percentiles. Whiskers indicate the lowest and highest values of the respective quartile, and dots present the added values of a single patient. Significances were calculated with either 1-way ANOVA (P<0.05) or Kruskal-Wallis test (P<0.05). A Bonferroni correction was applied post hoc.

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  Figure 2.. Differences in metabolomics parameters between control vs acute decompensated heart failure (ADHF) and control vs chronic heart failure (CHF). A, Principal component analysis (PCA) between control (red) and ADHF (green). Each point represents an individual with all of the 57 altered metabolites. The scheme shows the score plot of the top 2 principal components (PCs). PC 1 accounts for 52.1%, and PC 2 for 7.6% of the variance. The ellipses represent the 95% confidence region. B, Volcano plot depicts unstandardized signal (log2[fold change (FC)]) against noise-adjusted signal (−log10[P]) of control vs ADHF. The dots represent the altered metabolites using the Bonferroni-corrected P value (P≤0.05). FC thresholds were selected at −1 and 1. Grey dots did not pass the significance threshold. Black dots passed the significance threshold but not the FC threshold. Blue dots are decreased metabolites in ADHF with ≤0.5 FC (log2[0.5]=−1). Red dots are increased metabolites in ADHF with ≥2.0 FC (log2[2]=1). The significance threshold is 1.3 (−log10[0.05]). C, PCA between control (red) and CHF (green). Each point represents an individual with all of the 48 altered metabolites. The scheme shows…

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  Figure 3.. Differences in metabolomics parameters between control vs dilated cardiomyopathy (DCM) and control vs ischemic cardiomyopathy (ICM). A, Principal component analysis (PCA) between control (red) and DCM (green). Each point represents an individual with all of the 35 altered metabolites. The scheme shows the score plot of the top 2 principal components (PCs). PC 1 accounts for 44.4%, and PC 2 for 9.7% of the variance. The ellipses represent the 95% CI region. B, Volcano plot depicts unstandardized signal (log2[fold change (FC)]) against noise-adjusted signal (−log10[P]) of control vs DCM. The dots represent the altered metabolites using the Bonferroni-corrected P value (P≤0.05). FC thresholds were selected at −1 and 1. Grey dots did not pass the significance threshold. Black dots passed the significance threshold but not the FC threshold. Blue dots are decreased metabolites in DCM with ≤0.5 FC (log2[0.5]=−1). Red dots are increased metabolites in DCM with ≥2.0 FC (log2[2]=1). The significance threshold is 1.3 (−log10[0.05]). C, PCA between control (red) and ICM (green). Each point represents an individual with all of the 48 altered metabolites. The scheme shows the score plot of the…

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  Figure 4.. Area under the curve–receiver operating characteristic (AUC-ROC) analysis performed for 3-indolepropionic acid (3-IPA) and 1-methyl histidine (1-MetHis). A, AUC-ROC curve for control vs acute decompensated heart failure (ADHF). Dotted diagonal line represents a random guess. AUC (3-IPA), 0.93 (corrected AUC, 0.93; optimism, −0.003). AUC (1-MetHis), 0.89 (corrected AUC, 0.89; optimism, −0.002). B, AUC-ROC curve for control vs CHF. The dotted diagonal line represents a random guess. AUC (3-IPA), 0.82 (corrected AUC, 0.82; optimism, 0.001). AUC (1-MetHis), 0.86 (corrected AUC, 0.86; optimism, −0.002). C, AUC-ROC curve for control vs DCM. The dotted diagonal line represents a random guess. AUC (3-IPA), 0.80 (corrected AUC, 0.80; optimism, −0.001). AUC (1-MetHis), 0.81 (corrected AUC, 0.81; optimism, 0.002). D, AUC-ROC curve for control vs ICM. The dotted diagonal line represents a random guess. AUC (3-IPA), 0.83 (corrected AUC, 0.82; optimism, 0.009). AUC (1-MetHis), 0.91 (corrected AUC, 0.81; optimism, 0.001). BNP indicates brain natriuretic peptide.

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  Figure 5.. Uniquely altered metabolites between control vs acute decompensated heart failure (ADHF) and control vs chronic heart failure (CHF). A, Heatmap with the significantly and uniquely changed metabolites between control and ADHF. Columns depict 1 patient. Rows show the respective metabolite. B, Bar chart of the binary logistic regression (BLR) of all uniquely altered metabolites with their respective odds ratio between control and ADHF. The odds ratio threshold was set at 1.0. An odds ratio ≤1.0 indicates an increased probability of control. An odds ratio ≥1.0 indicates an increased probability for ADHF. Missing metabolites were not significant and removed from the graph. C, Area under the curve–receiver operating characteristic (AUC-ROC) curves for the metabolites with an odds ratio >1.0. The dotted diagonal line represents a random guess. AUC (C3-DC [C4-OH])=0.93 (corrected AUC, 0.93; optimism, 0.0002), AUC (SDMA), 0.89 (corrected AUC, 0.89; optimism, −0.002), AUC (C6 [C4:1-DC])=0.86 (corrected AUC, 0.85; optimism, 0.002), AUC (C18:1)=0.78 (corrected AUC, 0.78; optimism, 0.0006). D, Heatmap with the significantly and uniquely changed metabolites between control and CHF. Columns…

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  Figure 6.. Metabolic differences between acute decompensated heart failure (ADHF) vs chronic heart failure (CHF), ADHF vs dilated cardiomyopathy (DCM), and ADHF vs ischemic cardiomyopathy (ICM). A, Volcano plot depicts unstandardized signal (log2[fold change (FC)]) against noise-adjusted signal (−log10[P]) of ADHF vs CHF. The dots represent the altered metabolites using the Bonferroni-corrected P value (P≤0.05). FC thresholds were selected at −1 and 1. Grey dots did not pass the significance threshold. Black dots passed the significance threshold but not the FC threshold. Blue dots are decreased metabolites in ADHF with ≤0.5 FC (log2[0.5]=−1). The significance threshold is 1.3 (−log10[0.05]). B, Volcano plot depicts unstandardized signal (log2[FC]) against noise-adjusted signal (−log10[P]) of ADHF vs DCM. The dots represent the altered metabolites using the Bonferroni-corrected P value (P≤0.05). FC thresholds were selected at −1 and 1. Grey dots did not pass the significance threshold. Black dots passed the significance threshold but not the FC threshold. Blue dots are decreased metabolites in ADHF with ≤0.5 FC (log2[0.5]=−1). C, Volcano plot depicts unstandardized signal (log2[FC]) against…

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  Figure 7.. Differences in metabolic parameters between dilated cardiomyopathy (DCM) vs ischemic cardiomyopathy (ICM). A through H, Left, Depicted are significantly altered metabolites between DCM and ICM as a box plot. The box represents the 25th to 75th percentiles. Whiskers indicate the lowest and highest values of the respective quartile, and dots present the single measured value. Significance was calculated with a t test (P<0.05). A through H, Right, receiver operating characteristic (ROC) curves and area under the curve (AUC) of altered metabolites of DCM vs ICM. A, Serine (Ser; corrected AUC, 0.75; optimism, 0.0003). B, Lysophosphatidylcholine a C26:1 (corrected AUC, 0.78; optimism, 0.003). C, Cholesteryl ester (CE [16:0]; corrected AUC, 0.75; optimism, −0.008). D, CE (18:1; corrected AUC, 0.74; optimism, 0.005). E, CE (18:3; corrected AUC, 0.78; optimism, −0.001). F, CE (20:3; corrected AUC, 0.73; optimism, −0.002). G, CE (20:4; corrected AUC, 0.79; optimism, −0.005). H, CE (22:5; corrected AUC, 0.76; optimism, −0.001). The dotted diagonal line represents a random guess. BNP indicates brain natriuretic peptide.