Gender and environmental brain-derived neurotrophic effects on regional factor expression after experimental traumatic brain injury
Gender and environmental brain-derived neurotrophic effects on regional factor expression after experimental traumatic brain injury
复制标题
DOI：
10.1016/j.neuroscience.2005.05.041
复制
发表时间：
2005-01-01
期刊：
影响因子：
3.3
通讯作者：
Wagner, AK
中科院分区：
文献类型：
--
作者：
Chen, X;Li, Y;Wagner, AK
据报道，创伤性脑损伤后多个脑区的脑源性神经营养因子表达发生了急性变化，然而，损伤和损伤后环境丰富均未显示出长期损伤后雄性大鼠海马脑源性神经营养因子基因表达的影响。研究表明，雌性大鼠脑外伤后具有与激素相关的神经保护作用，雌激素和运动都会影响脑源性神经营养因子的水平。尽管最近的研究表明，创伤后脑损伤暴露于丰富的环境中可以改善雄性大鼠的认知恢复，但我们已经证明，环境丰富介导的空间学习改善具有性别特异性，并且仅对雄性大鼠产生积极影响。因此，本研究的目的是评估性别和环境丰富对慢性损伤后皮质和海马脑源性神经营养因子蛋白表达的影响。在受控皮质冲击或假手术后，将 Sprague-Dawley 雄性和骑自行车的雌性大鼠放入环境富集或标准住房中。手术后四周，使用蛋白质印迹检查海马和额叶皮层脑源性神经营养因子的表达。结果显示，男性损伤同侧额叶皮质中脑源性神经营养因子表达显着增加（P=0.03）。环境富集并没有增强这种效应。环境富集和损伤均未显着影响女性皮质脑源性神经营养因子的表达。在损伤同侧的海马中，雄性和雌性的脑源性神经营养因子表达均为标准环境中假手术中观察到的一半（分别为 49% 和 51%）。对于受伤的男性，该区域有一种环境富集的趋势，可以将脑源性神经营养因子水平恢复到假值。然而，与放置在标准住房中的假手术和受伤雌性相比，在环境富化中，受伤雌性损伤同侧的海马脑源性神经营养因子表达显着增加（P
Alterations in brain-derived neurotrophic factor expression have been reported in multiple brain regions acutely after traumatic brain injury, however neither injury nor post-injury environmental enrichment has been shown to affect hippocampal brain-derived neurotrophic factor gene expression in male rats chronically post-injury. Studies have demonstrated hormone-related neuroprotection for female rats after traumatic brain injury, and estrogen and exercise both influence brain-derived neurotrophic factor levels. Despite recent studies suggesting that exposure post-traumatic brain injury to environmental enrichment improves cognitive recovery in male rats, we have shown that environmental enrichment mediated improvements with spatial learning are gender specific and only positively affect males. Therefore the purpose of this study was to evaluate the effect of gender and environmental enrichment on chronic post-injury cortical and hippocampal brain-derived neurotrophic factor protein expression. Sprague-Dawley male and cycling female rats were placed into environmental enrichment or standard housing after controlled cortical impact or sham surgery. Four weeks post-surgery, hippocampal and frontal cortex brain-derived neurotrophic factor expression were examined using Western blot. Results revealed significant increases in brain-derived neurotrophic factor expression in the frontal cortex ipsilateral to injury for males (P=0.03). Environmental enrichment did not augment this effect. Neither environmental enrichment nor injury significantly affected cortical brain-derived neurotrophic factor expression for females. In the hippocampus ipsilateral to injury brain-derived neurotrophic factor expression for both males and females was half (49% and 51% respectively) of that observed in shams housed in the standard environment. For injured males, there was a trend in this region for environmental enrichment to restore brain-derived neurotrophic factor levels to sham values. However, there were robust increases in hippocampal brain-derived neurotrophic factor expression ipsilateral to the injury for injured females in environmental enrichment compared with both sham and injured females placed in standard housing (P