FIGURE 6.
Effect of pEXOs from patients with different grade of reverse ventricular remodeling on cardiomyocytes size. The HL-1 cells were seeded at a concentration of 5,000 cells/cm2 and allowed to adhere for 24 h before treatment. To enlarge cardiomyocyte size, HL-1 cells were treated with ± 1-μM Angiotensin II (AngII, Sigma) in complete Claycomb medium for 48 h. A PBS suspension of pEXOs isolated at T0 or T1 from HiR- or LoR-REM group (N = 4 patients/group) was added to a final concentration of 1 × 109 particles/ml, 24 h after the beginning of the treatment, and the treatment was maintained for the remaining 24 h; PBS was employed as a control. The cell monolayer was stained with Phalloidin-Atto 550 as described in the methods. The images were acquired with a fluorescence microscope (Leica; 20× magnification); the cell areas were manually measured with ImageJ software (https://imagej.nih.gov/ij/) and expressed in pixels. Statistical significance of the differences between treatments was evaluated by one-way ANOVA. The symbol “+” represents the significance of the differences against PBS alone (+, p < 0.05; ++, p < 0.01; ++++, p < 0.0001); “#” against PBS + AngII (####p < 0.0001); and “*” between LoR-REM and HiR-REM pEXO treatment in presence of AngII (****p < 0.0001).