减重步行训练对不完全脊髓损伤大鼠脚桥核可塑性影响的研究

目的:探索减重步行训练对不完全脊髓损伤大鼠脚桥核可塑性的影响。方法:将雌性SD大鼠24只分为减重步行训练组、未训练组和假手术组,每组8只,用美国NYU脊髓冲击损伤仪制作大鼠T10脊髓不完全损伤模型。采用PET-CT、免疫荧光染色及BBB评分观察减重步行训练对不完全脊髓损伤(iSCI)大鼠中脑运动区(MLR)脚桥核可塑性变化和后肢运动功能的改善。结果:减重步行训练组大鼠的后肢运动功能BBB评分在造模后4周、7周两个时间点的分值均较未训练组高(P0.05)。假手术组大鼠在造模后1周、4周、7周3个时间点的BBB评分值均明显高于训练组和未训练组(P0.01)。虽然训练组18F-氟脱氧葡萄糖(18F-FDG)的标准摄取值(SUV)的平均值较未训练组增高,而且假手术组的SUV值最高,但三组SUV值的差异不具有显著性意义(P0.05)。神经元特异性核抗原(NeuN)免疫荧光染色检测显示训练组、未训练组、假手术组三组间大鼠脚桥核的神经元数量差异无显著性意义(P0.05),而脚桥核2型囊泡谷氨酸转运体(VGLUT2)的积分光密度值(IOD)比较,假手术组IOD表达最高,训练组较未训练组明显增强(P0.01)。结论:减重步行训练能够明显提高iSCI大鼠后肢运动功能及其脚桥核中谷氨酸能信号传递,而且iSCI后大鼠中脑脚桥核的整体代谢及神经元数量无明显改变。因此认为脚桥核的谷氨酸表达增强是减重步行训练使iSCI大鼠后肢步行功能改善的原因之一。减重步行训练能使脚桥核发生神经递质表达层面的可塑性变化。     

骨髓间充质干细胞对髋部骨折诱导的老年大鼠急性肺损伤的保护机制

目的　探讨骨髓间充质干细胞（bone marrow-derived mesenchymal stem cells,BMSCs）对老年单侧髋部骨折大鼠急性肺损伤（acute lung injury, ALI）的保护作用。 方法　将15月龄雌性WISTAR大鼠分为对照组（不做任何处理）、模型组（右髋部骨折+生理盐水）、治疗组（右髋部骨折+BMSCs）。治疗组于造模后经尾静脉注射1 ml BMSCs(2.5×106/ml),模型组给予等体积生理盐水。创伤后24 h进行肺组织病理评分,ELISA法检测检测肺组织MPO含量、肺及血液炎症因子（TNF-α、IL-6、IL-10）水平。 结果　与对照组相比,模型组肺部病理学评分、肺组织MPO水平、肺及血液炎症反应相关指标均明显升高（P<0.01）。BMSCs处理可明显降低肺组织病理学评分,肺组织MPO水平、肺及血液炎症反应相关指标下调,同时IL-10水平有更明显的增高（P<0.01）。 结论 髋部骨折可诱发老年大鼠急性肺损伤,BMSCs移植对老年髋部骨折大鼠肺损伤具有保护作用,其机制与缓解全身及肺部炎症反应有关。     

骨髓基质干细胞对熏烟暴露老年大鼠髋部骨折后急性肺损伤的保护作用

BACKGROUND:The elderly hip fracture patients with chronic obstructive pulmonary disease (COPD) have a higher postoperative mortality than those only with hip fractures. In recent years, it has become an issue of concerns. Because the mechanism is unknown, however, there are no effective clinical interventions for these patients. OBJECTIVE:To observe the effect of bone marrow stromal stem cells (BMSCs) on the level of pulmonary inflammation in aged rats with chronic obstructive pulmonary disease (COPD) after hip fractures. METHODS:Thirty male Sprague-Dawley rats, 12 months old, were exposed to smoking for 4 months and randomized into three groups, smoking, smoking+hip fracture+normal saline, smoking+hip fracture+ BMSCs groups. Animal models of hip fracture were made in the latter two groups. Twenty-four hours after hip fracture, the lower lobe and peripheral blood samples were taken from all rats in the three groups, to evaluate the pathological changes of lung tissue and detect levels of inflammatory factors in the lung tissue and peripheral blood. RESULTS AND CONCLUSION:After closed hip fracture, aged COPD rats exhibited inflammatory cell infiltration, mucus secretion, airway stenosis or occlusion; the levels of interleukin-6, tumor necrosis factor-α and interleukin-10 in the lung tissue and peripheral blood were increased. After intravenous injection of BMSCs, the pathological changes of the lung tissue were reduced, and the levels of pro-inflammatory factors, tumor necrosis factor-α and interleukin-6, decreased, but the level of anti-inflammatory factor interleukin-10 further increased, which were significantly different from those in the normal saline group (P < 0.05). These findings indicate that BMSCs can relieve acute lung injury in aged COPD rats with hip fractures．