Prevention of bone loss by injection of insulin-like growth factor-1 after sciatic neurectomy in rats.

Objective: Injection of insulin-like growth factor-1 (IGF-1) can prevent bone loss in sciatic nerve transaction rats. We try to investigate the action mechanism of IGF-1 on bone formation.

Methods: A total of 40 adult male Spragne-Dawley rats were divided into two groups (experimental group and control group) with 20 animals in each.

Substance P stimulates differentiation of mice osteoblast through up-regulating Osterix expression.

Objective: To investigate the molecular pathway of substance P (SP) to induce osteoblastic differentiation.

Methods: Mesenchymal stem cells were isolated and cultured. The cultures were divided into four groups with Group A (control group) cultured without any factors, Group B cultured with SP, Group C cultured with SP and SP receptor neurokinin-1 (NK1) antagonist, and Group D cultured with SP NK1 antagonist respectively to induce osteoblastic cells differentiation.