title: Multiple injections of human umbilical cord-derived mesenchymal stromal cells through the tail vein improve microcirculation and the microenvironment in a rat model of radiation myelopathy.
abstract: BACKGROUND
  At present, no effective clinical treatment is available for the late effects of radiation myelopathy. The aim of the present study was to assess the therapeutic effects of human umbilical cord-derived mesenchymal stromal cells (UC-MSCs) in a rat model of radiation myelopathy.
  
  
  METHODS
  An irradiated cervical spinal cord rat model was generated. UC-MSCs were injected through the tail vein at 90, 97, 104 and 111 days post-irradiation. Behavioral tests were performed using the forelimb paralysis scoring system, and histological damage was examined using Nissl staining. The microcirculation in the spinal cord was assessed using von Willebrand factor (vWF) immunohistochemical analysis and laser-Doppler flowmetry. The microenvironment in the spinal cord was determined by measuring the pro-inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the serum and the anti-inflammatory cytokines brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) in the spinal cord.
  
  
  RESULTS
  Multiple injections of UC-MSCs through the tail veil decreased the forelimb paralysis, decreased spinal cord histological damage, increased the number of neurons in the anterior horn of the spinal cord, increased the endothelial cell density and the microvessel density in the white matter and gray matter of the spinal cord, increased the relative magnitude of spinal cord blood flow, down-regulated pro-inflammatory cytokine expression in the serum, and increased anti-inflammatory cytokine expression in the spinal cord.
  
  
  CONCLUSIONS
  Multiple injections of UC-MSCs via the tail vein in a rat model of radiation myelopathy significantly improved the microcirculation and microenvironment through therapeutic paracrine effects.
authors.forename: Li
authors.initials: L
authors.lastname: Wei
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiu-Bin
authors.initials: XB
authors.lastname: Xiao
authors.forename: Hai-Xing
authors.initials: HX
authors.lastname: Mai
authors.forename: Ke
authors.initials: K
authors.lastname: Zheng
authors.forename: Wan-Liang
authors.initials: WL
authors.lastname: Sun
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Feng
authors.initials: F
authors.lastname: Liang
authors.forename: Zai-Liang
authors.initials: ZL
authors.lastname: Yang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Yan-Qing
authors.initials: YQ
authors.lastname: Wang
authors.forename: Zhi-Fang
authors.initials: ZF
authors.lastname: Li
authors.forename: Jia-Ning
authors.initials: JN
authors.lastname: Wang
authors.forename: Wei-Jing
authors.initials: WJ
authors.lastname: Zhang
authors.forename: Hua
authors.initials: H
authors.lastname: You
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D004195:Disease Models, Animal; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells; D008833:Microcirculation; D011833:Radiation Injuries, Experimental / Q000628:therapy*; D051381:Rats; D013116:Spinal Cord / Q000503:physiopathology; D013118:Spinal Cord Diseases / Q000628:therapy*; D013623:Tail / Q000098:blood supply*; D014470:Umbilical Cord / Q000166:cytology*; D014680:Veins