title: Effect of whole body vibration therapy on circulating serotonin levels in an ovariectomized rat model of osteoporosis.
abstract: OBJECTIVE
  Studies have reported that whole body vibration (WBV) played a vital role in bone remodeling. Circulating serotonin is also involved in negative regulating bone mass in rodents and humans. However, both WBV and inhibition of serotonin biosynthesis may suppress receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclastogenesis in vitro. The purpose of the current study was to investigate the effect of WBV therapy on the levels of serum serotonin in ovariectomized rats.
  
  
  METHODS
  Thirty-six-month-old female Sprague Dawley rats weighing 276.15±37.75 g were ovariectomized to induce osteoporosis, and another ten rats underwent sham operation to establish sham control (SHAM) group. After 3 months, ovariectomized rats were divided into three subgroups and then separately treated with WBV, Alendronate (ALN) and normal saline (OVX), SHAM group was given normal saline. After 6 weeks of treatment, rats were sacrificed. Serum serotonin, RANKL, bone turnover markers, and bone mineral density (BMD), bone strength were evaluated.
  
  
  RESULTS
  The serum serotonin level was significantly lower in WBV group than OVX and ALN groups (P<0.05 and P<0.001). RANKL levels significantly decreased in WBV and ALN groups compared to OVX group (P<0.001 for both). BMD and biomechanical parameters of femur significantly increased (P<0.05 for both) and bone turnover levels decreased (P<0.001 for both) in WBV group compared to OVX group.
  
  
  CONCLUSIONS
  These data indicated that WBV enhanced the bone strength and BMD in ovariectomized rats most likely by reducing the levels of circulating serotonin.
authors.affiliation: Department of Rehabilitation, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China.
authors.forename: Qiu-Shi
authors.initials: QS
authors.lastname: Wei
authors.affiliation: Department of Rehabilitation, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China.
authors.forename: Li
authors.initials: L
authors.lastname: Huang
authors.affiliation: Department of Rehabilitation, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China.
authors.forename: Xian-Hong
authors.initials: XH
authors.lastname: Chen
authors.affiliation: Key Laboratory of Orthopaedics & Traumatology, Guangzhou University of Traditional Chinese Medicine, Guangzhou, China.
authors.forename: Hai-Bin
authors.initials: HB
authors.lastname: Wang
authors.affiliation: Department of Rehabilitation, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China.
authors.forename: Wei-Shan
authors.initials: WS
authors.lastname: Sun
authors.affiliation: Key Laboratory of Orthopaedics & Traumatology, Guangzhou University of Traditional Chinese Medicine, Guangzhou, China.
authors.forename: Shao-Chuan
authors.initials: SC
authors.lastname: Huo
authors.affiliation: Key Laboratory of Orthopaedics & Traumatology, Guangzhou University of Traditional Chinese Medicine, Guangzhou, China.
authors.forename: Zi-Qi
authors.initials: ZQ
authors.lastname: Li
authors.affiliation: Department of Rehabilitation, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China.
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Deng
keywords: Osteoporosis; Ovariectomy; Serotonin; Whole body vibration