摘要
In this study,we investigate how Schwann cells and dorsal root ganglion(DRG)neurons response to direct low-intensity pulsed ultrasound(LIPUS)stimuli in vitro.Primary Schwann cells and DRG were isolated from rat sciatic nerve and spine,respectively.LIPUS with varied dose of intensity(low:250 mW/cm2,medium:500 m W/cm2,high:750 m W/cm2)were applied 5 min per time for every other day,and pro-myelination indicators of Schwann cell as well as neurite outgrowth of dorsal root ganglion neurons were analyzed.Our results demonstrated that LIPUS promoted Schwann cells activity and proliferation from day 3 at the highest intensity,and day 5 at all intensities.In addition,LIPUS boosted pro-myelination activities of Schwann cells,as evidenced by increased cell population that positive for immunohistochemical staining against S100,nerve growth factor receptor(NGFR)p75,glial fibrillary acidic protein(GFAP),myelin protein zero(P0),as well as up-regulation of GFAP,Protein 0,nerve growth factor(NGF),and brain derived neurotrophic factor(BDNF)genes.Furthermore,LIPUS significantly enhanced the neurite outgrowth of DRG,with the highest intensity exhibiting longest neurite outgrowth.Taken together,our results strongly improve the understanding of cellular mechanisms of ultrasonic therapies for peripheral nerve repair.
基金
Supported by the National Natural Science Foundation of China(81327003)