Histological Study of the Effect of Adipose Tissue Derived Stem Cells on the Regeneration of Injured Skeletal Muscle in Albino Rat Model

Muscle injuries in sport activities can pose challenging problems in sports medicine. The best treatment for muscle injury has not been clearly established except for the conservative treatment that is routinely performed. The aim of the present study was to investigate whether adipose-derived stem cells could contribute to skeletal muscle healing. Thirty two adult male albino rats were included in the present study. They were classified into the following groups. Group1: served as control (sham) group. Group II; in which laceration was induced in the triceps muscle and rats were sacrificed 2, 4 weeks later (group IIa, IIb) respectively. Group III; stem cell treated group in which ADSCs were injected at the site of laceration at a dose of one million cells for each rat and sacrificed and sacrificed 2,4 weeks later (group IIIa,IIIb). Sections from skeletal muscle were stained with H& E stain, Masson’s trichrome stain, Prussian blue stain and immunohistochemical staining for CD-90 (stem cell marker) and VEGF. The number of centronucleated muscle fibers, the area% of collagen and VEGF immunoreactivity were measured using the image analyser. The results were statistically analyzed. Two weeks after stem cell injection, the mean numbers of centronucleated regenerating myofibers were significantly higher in ADSC treated group than they were in lacerated group. However no significant difference could be detected at 4 weeks. ADSCs treatment didn’t decrease collagen deposition. CD90 positive ADSCs could be detected in muscle tissue 2 weeks after injection but not after 4 weeks. VEGF immunoreactivity was significantly increased in stem cell treated group (IIIa).It could be concluded that ADSCs therapy may accelerate muscle repair and improve the histological structure of skeletal muscle after injury.