Document Type : Original Article


1 Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran‎

2 Department of Pathobiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran‎

3 Department of Surgery and Diagnostic Imaging, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran‎

4 Department of Chemical Engineering, Sahand University of Technology, Tabriz, Iran‎


Skeletal muscle atrophy induced by denervation is one of the common disorders in traumatic nerve injuries. The aim of this study was the evaluation of histomorphometrical changes of extensor digitorum longus muscle after denervation and its regeneration by tissue engineering. Ninety adult male Wistar rats were randomly divided into six main groups (n = 15) in three time periods (2, 4 and 8 weeks; n = 5). Control group was treated without surgery, in transection (Tr) group left sciatic nerve was transected, in scaffold (S) group only collagen gel scaffold was used, in mast cell (MC) group mast cells were used, mesenchymal stem cell (MSC) group was treated with mesenchymal stem cells and in MC+MSC group, mast cells along with mesenchymal stem cells were used. In the cellular groups, the scaffold and cells were mixed and placed in the transected nerve gap. The average diameter of muscle fibers, ratio of the muscle fibers nuclei to the fibrocytes nuclei (mn/fn), ratio of the muscle fibers nuclei number to the muscle fibers number (mn/mf), the average ratio of blood vessels to muscle fibers number (v/mf) and muscles weight in Tr group were the lowest compared to the other groups; but, in cellular and S groups, amelioration was observed according to the time period. However, in MC+MSC group, there were the highest ameliorative results. This study revealed that simultaneous use of MCs and MSCs mixed with collagen gel scaffold can be considered as a suitable approach to improve denervated skeletal muscle atrophy associated with sciatic nerve injury.


  1. Wiberg M, Terenghi Will it be possible to produce peripheral nerves? Surg technol Int 2003; 11: 303-310.
  2. Whitlock EL, Tuffaha SH, Luciano JP, et al. Processed allografts and type I collagen conduits for repair of peripheral nerve gaps. Muscle Nerve 2009; 39(6): 787-799.
  3. Cheng XL, Wang P, Sun B, et al. The longitudinal epineural incision and complete nerve transection method for modeling sciatic nerve injury. Neural Regen Res 2015; 10(10): 1663-1668.
  4. McKenna CF, Fry CS. Altered satellite cell dynamics accompany skeletal muscle atrophy during chronic illness, disuse, and aging. Curr Opin Clin Nutr Metab Care 2017; 20(6): 447-452.
  5. Canu M-H, Garnier C, Lepoutre F-X, et al. A 3D analysis of hind limb motion during treadmill locomotion in rats after a 14-day episode of simulated microgravity. Behav Brain Res. 2005; 157(2): 309-321.
  6. Baldwin KM, Haddad F, Pandorf CE, et al. Alterations in muscle mass and contractile phenotype in response to unloading models: role of transcriptional/ pretranslational mechanisms. Front Physiol 2013; 4: 284. doi: 10.3389/fphys.2013.00284.
  7. Zeman RJ, Zhao J, Zhang Y, et al. Differential skeletal muscle gene expression after upper or lower motor neuron transection. Pflugers Arch 2009; 458(3): 525-535.
  8. Carlson BM. The biology of long-term denervated skeletal muscle. Eur J Trans Myol 2014; 24(1): 3293. doi: 10.4081/ejtm.2014.3293.
  9. Rochkind S, Geuna S, Shainberg A. Chapter 25: Phototherapy in peripheral nerve injury: effects on muscle preservation and nerve regeneration. Int Rev Neurobiol 2009; 87: 445-464.
  10. Frattini F, Pereira Lopes FR, Almeida FM, et al. Mesenchymal stem cells in a polycaprolactone conduit promote sciatic nerve regeneration and sensory neuron survival after nerve injury. Tissue Eng Part A 2012; 18(19-20): 2030-2039.
  11. Arentson-Lantz EJ, English KL, Paddon-Jones D, et al. Fourteen days of bed rest induces a decline in satellite cell content and robust atrophy of skeletal muscle fibers in middle-aged adults. J Appl Physiology (1985) 2016; 120(8): 965-975.
  12. Nakanishi R, Hirayama Y, Tanaka M, et al. Nucleoprotein supplementation enhances the recovery of rat soleus mass with reloading after hindlimb unloading-induced atrophy via myonuclei accretion and increased protein synthesis. Nutr Res 2016; 36(12): 1335-1344.
  13. Yehya M, Torbey MT. The role of mast cells in intracerebral hemorrhage. Neurocrit Care 2018; 28(3): 288-295.
  14. Undem BJ, Myers AC, Weinreich D: Antigen-induced modulation of autonomic and sensory neurons in vitro. Int Arch Allergy Appl Immunol 1991; 94(1-4): 319-324.
  15. Ratzlaff RE, Cavanaugh VJ, Miller GW, et al. Evidence of a neurogenic component during IgE-mediated inflammation in mouse skin. J Neuroimmunol 1992; 41(1): 89-96.
  16. Murphy PG, Borthwick LS, Johnston RS, et al. Nature of the retrograde signal from injured nerves that induces interleukin-6 mRNA in neurons. J Neurosci 1999; 19(10): 3791-3800.
  17. van der Kleij HPM, Bienenstock J. Significance of conversation between mast cells and nerves. Allergy Asthma Clin Immunol. 2005; 1(2): 65-80.
  18. Nazari M, Ni NC, Lüdke A, et al. Mast cells promote proliferation and migration and inhibit differentiation of mesenchymal stem cells through PDGF. JMol Cell Cardiol 2016; 94: 32-42.
  19. Nakamura T, Inada Y, Fukuda S, et al. Experimental study on the regeneration of peripheral nerve gaps through a polyglycolic acid–collagen (PGA–collagen) tube. Brain Res 2004; 1027(1-2): 18-29.
  20. Ao Q, Fung CK, Tsui AYP, et al. The regeneration of transected sciatic nerves of adult rats using chitosan nerve conduits seeded with bone marrow stromal cell-derived Schwann cells. Biomaterials 2011; 32(3): 787-796.
  21. Batt JAE, Bain JR. Tibial nerve transection-a standardized model for denervation-induced skeletal muscle atrophy in mice. J Vis Exp 2013;(81): e50657. doi: 10.3791/50657.
  22. Rigon F, Horst A, Kucharski LC, et al. Effects of sciatic nerve transection on glucose uptake in the presence and absence of lactate in the frog dorsal root ganglia and spinal cord. Braz J Biol 2014; 74(3: S1): S191-S198.
  23. Humason GL. Annual tissue techniques. 4th San Francisco, USA: W H Freeman 1979; 35-47, 119-120.
  24. Mortaz E, Redegeld FA, Nijkamp FP, et al. Dual effects of acetylsalicylic acid on mast cell degranulation, expression of cyclooxygenase- 2 and release of pro-inflammatory cytokines. Biochem Pharmacol. 2005; 69(7): 1049-1057.
  25. Ginis I, Grinblat B, Shirvan MH. Evaluation of bone marrow-derived mesenchymal stem cells after cryo-preservation and hypothermic storage in clinically safe medium. Tissue Eng Part C Methods 2012; 18(6): 453-463.
  26. Schmidt MM, Dornelles RC, Mello RO, et al. Collagen extraction process. International Food Research Journal 2016; Aug 1: 23(3).
  27. Brooks SV, Faulkner JA. Skeletal muscle weakness in old age: underlying mechanisms. Med Sci Sports and Exerc 1994; 26(4): 432-439.
  28. Siu PM, Alway SE. Mitochondria‐associated apoptotic signalling in denervated rat skeletal muscle. J Physiol 2005; 565(Pt 1): 309-323.
  29. Tews DS. Apoptosis and muscle fibre loss in neuromuscular disorders. Neuromuscul Disord 2002; 12(7-8): 613-622.
  30. Pellegrino C, Franzini C. An electron microscope study of denervation atrophy in red and white skeletal muscle fibers. J Cell Biol 1963; 17(2): 327-349.
  31. Cea LA, Cisterna BA, Puebla C, et al. De novo expression of connexin hemichannels in denervated fast skeletal muscles leads to atrophy. Proc Natl Acad Sci U S A 2013; 110(40): 16229-16234.
  32. Salzer JL, Bunge RP. Studies of Schwann cell proliferation. I. An analysis in tissue culture of proliferation during development, Wallerian degeneration, and direct injury. J Cell Biol 1980; 84(3): 739-752.
  33. Reidy PT, McKenzie AI, Brunker P, et al. Neuromuscular electrical stimulation combined with protein ingestion preserves thigh muscle mass but not muscle function in healthy older adults during 5 days of bed rest. Rejuvenation Res 2017; 20(6): 449-461.
  34. Xing H, Zhou M, Assinck P, et al. Electrical stimulation influences satellite cell differentiation after sciatic nerve crush injury in rats. Muscle Nerve 2015; 51(3): 400-411.
  35. Liu W, Wei-LaPierre L, Klose A, et al. Inducible depletion of adult skeletal muscle stem cells impairs the regeneration of neuromuscular junctions. Elife 2015; 4: e09221. doi: 10.7554/eLife.09221.
  36. Wagoner LE, Merrill W, Jacobs J, et al. Abstract 2048: Angiogenesis protein therapy with human fibroblast growth factor (fgf-1): results of a phase I open label, dose escalation study in subjects with CAD not eligible for PCI or CABG. Circulation 2007; 116(Suppl_16): 443.
  37. Hiromatsu Y, Toda S. Mast cells and angiogenesis. Microsc Res Tech 2003; 60(1): 64-69.
  38. Leon A, Buriani A, Dal Toso R, et al. Mast cells synthesize, store, and release nerve growth factor. Proc Natl Acad Sci USA 1994; 91(9): 3739-3743.
  39. Carmeliet P, Tessier-Lavigne M. Common mechanisms of nerve and blood vessel wiring. Nature 2005; 436(7048):193-200.
  40. Hudlicka O, Brown M, Egginton S. Angiogenesis in skeletal and cardiac muscle. Physiol Rev 1992; 72(2): 369-417.
  41. Borisov AB, Huang SK, Carlson BM. Remodeling of the vascular bed and progressive loss of capillaries in denervated skeletal muscle. Anat Rec 2000; 258(3): 292-304.
  42. Giusti G, Willems WF, Kremer T, et al. Return of motor function after segmental nerve loss in a rat model: comparison of autogenous nerve graft, collagen conduit, and processed allograft (AxoGen). J Bone Joint Surg Am 2012; 94(5): 410-417.