Fig. 5.

Intraosseous DEC (1 × 10⁶ and 5 × 10⁶) administration results in reduced fibrosis in the heart, diaphragm, and gastrocnemius muscle at 180 days after transplant. (A) Picro-Sirius staining of heart cross-sections assessing fibrosis after DEC therapy compared to vehicle and WT controls; fibrotic collagenous tissue (red), muscle fibers (yellow). Magnification 20x, scale bar = 50 µm, n = 3/group, 12 ROI/organ/mouse. (B) In the cardiac muscle, significant reduction of fibrosis was observed in both DEC-injected groups compared to vehicle-injected controls. Trichrome stained cross-sections of diaphragm (C) and gastrocnemius muscle (E) confirmed significantly reduced fibrosis in both DEC-injected mice compared to vehicle-injected controls. Blue-stained areas represent collagenous tissue (fibrosis) and red-stained areas represent muscle fibers. Magnification 20x, scale bars = 100 µm. (D) In the diaphragm sections, significant, dose-dependent reduction of fibrosis was observed in both DEC-injected but not vehicle- injected mice. (F) In gastrocnemius muscle, significant decrease of fibrosis was observed in both DEC-injected groups compared to vehicle-injected controls. Fibrosis was measured and normalized to total tissue area. Data presented as mean ± SEM. Two sample t-test assuming unequal variances. Abbreviations: *p < 0.05, **p < 0.01, *** p < 0.001, **** p < 0.0001