A Specific Circulating MicroRNA Cluster Is Associated to Late Differential Cardiac Response to Doxorubicin-Induced Cardiotoxicity In Vivo

Figures

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  Figure 1. Experimental design. Treatment protocol for our animal model of DOX-induced cardiotoxicity. Arrows indicate single 4 mg/kg intraperitoneal DOX/saline injections. The horizontal blue bars indicate experimental endpoints when echocardiography was conducted. Each group was composed of ten animals.

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  Figure 2. Differential cardiac response to doxorubicin treatment. Unsupervised clustering based on cardiac functional parameters at T0 (a) and T42 (b). At T0, all animals were grouped together. At T42, a cluster of drug-treated animals was clearly separated (Tox) from those unaffected (NoTox) by doxorubicin and CTRLs. Cardiac functional parameters: LVEF: left ventricular ejection fraction; LVFS: left ventricular fractional shortening; LVDD: left ventricular diastolic diameter; LVSD: left ventricular systolic diameter; LVDV: left ventricular diastolic volume; LVSV: left ventricular systolic volume.

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  Figure 3. Cardiac dysfunction assessment. Cardiac parameter variation between baseline and T42 analyzed in each animal group: CTRL (blue), NoTox (green) and Tox (red). LVEF: left ventricular ejection fraction; LVFS: left ventricular fractional shortening; LVSV: left ventricular systolic volume; LVDV: left ventricular diastolic volume; LVSD: left ventricular internal systolic diameter; LVDD: left ventricular internal diastolic diameter. # p < 0.05, ## p < 0.01, ### p < 0.001 Tox vs. CTRL; ∗ = p < 0.05; ∗∗ = p < 0.01, ∗∗∗ = p < 0.001 Tox vs. NoTox; §§§ = p < 0.001 Tox T42 vs. Tox T0. CTRL n = 10; NoTox n = 5; Tox n = 4.

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  Figure 4. Plasma miRNAs are regulated upon doxorubicin treatment. Eight miRNAs showed dysregulated expression upon DOX treatment (vs. CTRL). Data are depicted as scatter plots and expressed as mean fold change ± SD vs. CTRL, arbitrarily set to 1. Controls: blue dots, NoTox: green dots, Tox: red dots. ∗ p < 0.05. CTRL n = 10; NoTox n = 5; Tox n = 4.

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  Figure 5. Plasma miRNAs can be used to identify doxorubicin response in treated animals. Multidimensional scaling analysis was used to investigate whether the expression of regulated plasma miRNAs could be used to correctly identify treated animals showing different cardiac responses to doxorubicin. (a) All Tox miRNAs were used for unsupervised clustering. A good accuracy was observed in separating the three groups of animals. (b) We identified a restricted miRNA cluster (miR-1-3p, miR-34a-5p, miR-133a-3p, and miR-499a-5p) correctly separating Tox/NoTox mice. Blue: CTRL; green: NoTox; red: Tox. aSI: average silhouette index. CTRL n = 10; NoTox n = 5; Tox n = 4.