title: Low-frequency vibration treatment of bone marrow stromal cells induces bone repairin vivo.
abstract: OBJECTIVE
  To study the effect of low-frequency vibration on bone marrow stromal cell differentiation and potential bone repairin vivo.
  
  
  METHODS
  Forty New Zealand rabbits were randomly divided into five groups with eight rabbits in each group. For each group, bone defects were generated in the left humerus of four rabbits, and in the right humerus of the other four rabbits. To test differentiation, bones were isolated and demineralized, supplemented with bone marrow stromal cells, and implanted into humerus bone defects. Varying frequencies of vibration (0, 12.5, 25, 50, and 100 Hz) were applied to each group for 30 min each day for four weeks. When the bone defects integrated, they were then removed for histological examination. mRNA transcript levels of runt-related transcription factor 2, osteoprotegerin, receptor activator of nuclear factor κ-B ligan, and pre-collagen type 1 α were measured.
  
  
  RESULTS
  Humeri implanted with bone marrow stromal cells displayed elevated callus levels and wider, more prevalent, and denser trabeculae following treatment at 25 and 50 Hz. The mRNA levels of runt-related transcription factor 2, osteoprotegerin, receptor activator of nuclear factor κ-B ligand, and pre-collagen type 1 α were also markedly higher following 25 and 50 Hz treatment.
  
  
  CONCLUSIONS
  Low frequency (25-50 Hz) vibrationin vivocan promote bone marrow stromal cell differentiation and repair bone injury.
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Shengwei
authors.initials: S
authors.lastname: He
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Wenzhi
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Lidong
authors.initials: L
authors.lastname: Mi
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Guangyu
authors.initials: G
authors.lastname: Du
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Chuanxiu
authors.initials: C
authors.lastname: Sun
authors.affiliation: Department of Orthopedics, Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province, 116031, P. R. China.
authors.forename: Xuegang
authors.initials: X
authors.lastname: Sun
keywords: Bone injury; Bone marrow stromal cells; Pre-Col1a; RUNX2