Article

Traumatic brain injury (TBI) can affect bone by influencing the
production/actions of pituitary hormones and neuropeptides that play significant
regulatory roles in bone metabolism. Previously, we demonstrated that
experimental TBI exerted a negative effect on the skeleton. Since mild TBI (mTBI)
accounts for the majority of TBI cases, this study was undertaken to evaluate TBI
effects using a milder impact model in female mice. Repetitive mTBI caused
microhemorrhaging, astrocytosis, and increased anti-inflammatory protective
actions in the brain of the impacted versus control mice 2 wk after the first
impact. Serum levels of growth regulating insulin-like growth factor 1 (IGF-I)
were reduced by 28.9%. Bone mass was reduced significantly in total body as well
as individual skeletons. Tibial total cortical density was reduced by 7.0%, which
led to weaker bones, as shown by a 31.3% decrease in femoral size adjusted peak
torque. A 27.5% decrease in tibial trabecular bone volume per total volume was
accompanied by a 34.3% (p = 0.07) decrease in bone formation rate (BFR) per total
area. Based on our data, we conclude that repetitive mTBI exerted significant
negative effects on accrual of both cortical and trabecular bone mass in mice
caused by a reduced BFR.

Langue : ANGLAIS