title: Erythropoietin improves functional and histological recovery of traumatized skeletal muscle tissue.
abstract: Apart from its hematopoietic effect, erythropoietin (EPO) is known as pleiotropic cytokine with anti-inflammatory and anti-apoptotic properties. Here, we evaluated for the first time the EPO-dependent regeneration capacity in an in vivo rat model of skeletal muscle trauma. A myoblast cell line was used to study the effect of EPO on serum deprivation-induced cell apoptosis in vitro. A crush injury was performed to the left soleus muscle in 80 rats treated with either EPO or saline. Muscle recovery was assessed by analysis of contraction capacities. Intravital microscopy, BrdU/laminin double immunohistochemistry and cleaved caspase-3 immunohistochemistry of muscle tissue on days 1, 7, 14, and 42 posttrauma served for assessment of local microcirculation, tissue integrity, and cell proliferation. Serum deprivation-induced myoblast apoptosis of 23.9 +/- 1.5% was reduced by EPO to 17.2 +/- 0.8%. Contraction force analysis in the EPO-treated animals revealed significantly improved muscle strength with 10-20% higher values of twitch and tetanic forces over the 42-day observation period. EPO-treated muscle tissue displayed improved functional capillary density as well as reduced leukocytic response and consecutively macromolecular leakage over day 14. Concomitantly, muscle histology showed significantly increased numbers of BrdU-positive satellite cells and interstitial cells as well as slightly lower counts of cleaved caspase-3-positive interstitial cells. EPO results in faster and better regeneration of skeletal muscle tissue after severe trauma and goes along with improved microcirculation. Thus, EPO, a compound established as clinically safe, may represent a promising therapeutic option to optimize the posttraumatic course of muscle tissue healing.
authors.affiliation: Department of Trauma and Reconstructive Surgery, University of Rostock, 18055 Rostock, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Rotter
authors.forename: Marija
authors.initials: M
authors.lastname: Menshykova
authors.forename: Tobias
authors.initials: T
authors.lastname: Winkler
authors.forename: Georg
authors.initials: G
authors.lastname: Matziolis
authors.forename: Ioannis
authors.initials: I
authors.lastname: Stratos
authors.forename: Matthias
authors.initials: M
authors.lastname: Schoen
authors.forename: Thomas
authors.initials: T
authors.lastname: Bittorf
authors.forename: Thomas
authors.initials: T
authors.lastname: Mittlmeier
authors.forename: Brigitte
authors.initials: B
authors.lastname: Vollmar
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000494:pharmacology*; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D053580:Muscle Strength / Q000187:drug effects / Q000502:physiology; D018482:Muscle, Skeletal / Q000098:blood supply / Q000293:injuries* / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D017467:Receptors, Erythropoietin / Q000378:metabolism; D020127:Recovery of Function / Q000187:drug effects / Q000502:physiology; D012038:Regeneration / Q000187:drug effects* / Q000502:physiology*; D013997:Time Factors; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology
chemical_list: D017467:Receptors, Erythropoietin; D004921:Erythropoietin