经皮迷走神经电刺激对骨髓炎大鼠骨破坏的影响及机制研究

Effects and mechanism of transcutaneous vagus nerve electrical stimulation on osteolytic destruction in rats with osteomyelitis

目的:观察经皮迷走神经电刺激(tVNS)对骨髓炎(OM)大鼠骨破坏的影响,探讨tVNS改善骨破坏的机制。方法:按照实验方法将大鼠分为阴性对照组(Control组)、伪刺激对照组(Sham-tVNS组)和实验组(tVNS组),每组15只。各组大鼠均以约含3×10^(8) CFU/ml金黄色葡萄球菌的10 μl PBS注入大鼠骨髓腔内制备OM模型,造模后根据分组情况予以相应的处理。通过小动物CT(Micro-CT)评估OM大鼠骨破坏情况,采用ELISA检测各组血浆中炎症因子水平及血浆和骨组织中乙酰胆碱含量,采用细菌培养法观察骨组织的感染情况。 结果:与Control组和Sham-tVNS组相比,tVNS组OM大鼠骨体积分数、骨小梁数量、骨密度增加,骨小梁分离度减小,血浆中炎症因子水平降低,血浆乙酰胆碱浓度和骨组织中乙酰胆碱含量增高,差异均有统计学意义( P<0.05);tVNS组OM大鼠骨组织培养形成的菌落数少于Sham-tVNS组及Control组,表明tVNS组骨组织中金黄色葡萄球菌被抑制。 结论:tVNS减小了OM大鼠骨破坏的范围,其机制可能与tVNS促进血浆与骨组织乙酰胆碱释放、抑制炎症反应及金黄色葡萄球菌生长有关。

ObjectiveTo observe the effect of transcutaneous vagus nerve electrical stimulation(tVNS)on osteolytic destruction in rats with osteomyelitis(OM),and to explore the mechanism of tVNS in ameliorating osteolytic destruction.MethodsThe rats were divided into three groups:negative control group(Control group),sham stimulation control group(Sham-tVNS group),and experimental group(tVNS group),with 15 rats in each.The OM model was established by injecting 3×10^(8) CFU/ml Staphylococcus aureus into rats’marrow cavity.After the models were successfully established,the rats in each group were treated according to the experiment design.Bone destruction of OM was evaluated by Micro-CT.The change of inflammatory factor levels in serum,and acetylcholine(Ach)content in serum and bone tissue in three groups were detected by ELISA.The infections in bone tissue were observed by agarose culture method.ResultsCompared with the rats in the Control group and the Sham-tVNS group,the OM rats in the tVNS group showed alleviated bone volume/total volume,trabecular number,and bone mineral density,reduced trabecular spacing,decreased serum inflammatory factor levels,and increased concentration of serum Ach and contents of Ach in bone tissues,with statistically significant differences(all P<0.05).The colonies of Staphylococcus aureus in bone tissue of the OM rats in the tVNS group was less than those in the Sham-tVNS and the Control group,indicating the Staphylococcus aureus in the tVNS group were inhibited.ConclusionThe tVNS can reduce the bone destruction in OM rats,and the mechanism was closely related to the tVNS promoting Ach release in plasma and bone tissue,and inhibiting inflammatory factors and the growth of Staphylococcus aureus.