Comparative Study on the Effect of Bone Marrow versus Adipose Tissue Derived Mesenchymal Stem Cells on Experimental Skeletal Muscle Injury in Rats

Abstract

Introduction: Skeletal muscle injury can result from a variety of mechanisms, including contusion, strain, laceration, or a combination of these mechanisms. Lesions originating by trauma are associated with loss of healthy muscular tissue and development of fibrous tissue scar with irreversible atrophy .Stem cells as a part regenerative therapy could overcome these limitations and improve skeletal muscle regeneration. Aim of the work: to compare between the effects of mesenchymal stem cells derived from the bone marrow versus those derived from the adipose tissue in treatment of skeletal muscle injury in female albino rats. Materials and Methods: Fifty adult female albino rats weighing 150-200gm were included in the study. They were divided into four groups: Group I (Control), Group II (untreated group) in which skeletal muscle laceration injury was induced and left for spontaneous healing,Group III in which the rats received a single dose of 106 BM-MSCs via IM at the site of injury, Group IV in which the rats received a single dose of 106ADSCs via IM at the site of injury. Skeletal muscle specimens were prepared for histological examination using H/E and Mallory trichrome stain. Also muscle specimens for detection of y chromosome in stem cells treated group by using PCR. Morphometric study and statistical analysis were performed. Results: Histological examination of the skeletal muscle laceration injury in the untreated group revealed a gap filled with granulation tissue. There was disruption of the muscle fibers with vacuolation in the cytoplasm and pyknotic nuclei. After 2 weeks, there was significant increase in the collagen fiber deposition in the interstitium. The BM-MSCs treated group showed better regeneration of the muscle fibers through the appearance of centronucleated regenerating myotubes but the interstitium also showed increased collagen deposition. Meanwhile, the ADSCs treated group showed significant increase in the regenerating centronucleated myotubes without an increase in the collagen fiber deposition.Conclusion: Inramuscular injection of ADSCs is preferable than BM-MSCs in the treatment of skeletal muscle laceration injury. Key words: Skeletal muscle laceration injury, BM-MSCs Bone marrow mesenchymal stem cells, ADSCs Adipose derived stem cells, Rat.