title: Mechanical-tactile stimulation (MTS) intervention in a neonatal stress model improves long-term outcomes on bone.
abstract: OBJECTIVE
  Neonatal stress impairs postnatal bone mineralization. Evidence suggests that mechanical tactile stimulation (MTS) in early life decreases stress hormones and improves bone mineralization. Insulin-like growth factor (IGF1) is impacted by stress and essential to bone development. We hypothesized that MTS administered during neonatal stress would improve bone phenotype in later life. We also predicted an increase in bone specific mRNA expression of IGF1 related pathways.
  
  
  METHODS
  Neonatal stress (STRESS) and MTS (STRESS+10 min of MTS) were given from D6 to D10 of rat life and tissue was harvested on D60 of life. Dual energy x-ray absorptiometry (DXA), bone morphometry, serum osteocalcin, type I procollagen N-terminal propeptide (PINP), tartrate-resistant acid phosphatase (TRAP), and bone and liver mRNA levels of IGF1, IGF1 receptor (IGF1R), and growth hormone receptor (GHR) were measured.
  
  
  RESULTS
  Stress resulted in reduced bone area and bone mineral content (BMC) compared to naive control (CTL). MTS intervention increased BMC and tibial growth plate width compared to STRESS. MTS also resulted in higher osteocalcin, and, in males, lower TRAP (p<0.05). MTS resulted in three-fold, two-fold, and six-fold higher bone specific IGF1, IGF1R, and GHR, respectively (p ≤ 0.001) compared to STRESS.
  
  
  CONCLUSIONS
  MTS in early postnatal life improves long-term bone mineralization. IGF1 and related pathways may explain improved BMC.
authors: Center for Pediatric Nutrition Research, University of Utah, Salt Lake City, Utah.
authors: S
authors: S
authors: Haley
authors: S
authors: S
authors: O'Grady
authors: K
authors: K
authors: Gulliver
authors: B
authors: B
authors: Bowman
authors: R
authors: R
authors: Baldassarre
authors: S
authors: S
authors: Miller
authors: R H
authors: RH
authors: Lane
authors: L J
authors: LJ
authors: Moyer-Mileur
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001846:Bone Development / Q000502:physiology*; D001862:Bone Resorption / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D010812:Physical Stimulation / Q000379:methods; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013315:Stress, Psychological / Q000150:complications / Q000503:physiopathology* / Q000628:therapy*; D014110:Touch / Q000502:physiology*