Intraventricular Administration Of Bmp-7 In Stroke

中风和相关血管事件可引起中枢神经系统（CNS）的广泛损伤，并导致严重的运动和认知障碍。有研究表明，营养因子治疗可以减轻损伤程度，恢复损伤后的神经元。我们之前已经测试了骨形态发生蛋白-7 （BMP-7）在局灶性脑缺血损伤中的作用，BMP-7是生长因子转化因子- b超家族的一员。我们发现脑室内给药后BMP-7具有深远的神经保护作用。我们现在已经开始测试它在缺血脑中的分布，以确定BMP-7通过脑实质扩散的速度。我们还确定了它是否在损伤后短期内对神经元中中间丝的表达有影响，作为其恢复活性的部分基础。最后，我们检查了中风后对运动行为的影响。成年雄性Sprague-Dawley大鼠右大脑中动脉闭塞60分钟，24小时后，向同侧侧脑室注射25 ul （1 ug/ul）剂量的BMP-7或载药。在给药后1、3、6和24小时处死动物。在脑实质定位方面，我们发现BMP-7在注射后1小时主要存在于室管膜，而在注射后3小时扩展到邻近的少数神经元。然而，6小时组和24小时组在神经元中都有显著的bmp -7免疫反应标记，主要是纹状体和丘脑。在接受载体注射的动物中，注射侧的神经丝表达似乎相当弱，而在注射BMP-7后6和24小时，观察到神经丝染色明显上调。24小时观察到显著的神经突生长，具有明显的生长锥体，特别是在腹侧纹状体和伏隔体。这些结果表明，注射BMP-7可能有助于缺血性损伤后中间神经元纤维的表达，而且注射的因子可以被纳入距离侧脑室几毫米的神经元中。用水合氯醛麻醉成年sd大鼠。大脑中动脉（MCA）被通过右颈内动脉插入的细丝短暂阻塞。缺血60分钟后取出纤维，进行再灌注。部分动物在MCA闭塞（MCAo）后24小时处死，检测BMP-7 mRNA表达。其他动物在MCA闭塞后24小时接受单剂量静脉注射BMP-7或载药，并用于随后的行为研究和BMP-7免疫染色。未处理动物MCAo后24小时BMP-7 mRNA表达上调。静脉注射BMP-7的动物在MCAo后第6天，缺血侧海马/齿状体的BMP-7免疫反应性呈剂量依赖性增加。在MCAo后第7天至第14天，接受BMP-7治疗的动物也表现出身体不对称的减少，第14天的运动活动增加。我们的数据表明，脑卒中后静脉注射BMP-7可以通过缺血侧的血脑屏障，并在较长的测试时间内诱导脑卒中动物的行为恢复。

Stroke and related vascular events can cause widespread damage to the central nervous system (CNS) and result in significant motor and cognitive impairments. It has been suggested that trophic factor treatment may reduce the extent of damage and restore damaged neurons following the injury. We have previously tested the effects of bone morphogenetic protein-7 (BMP-7), a member of the transforming growth factor-B superfamily of growth factors, in focal brain ischemic injury. We found BMP-7 to have profound neuroprotective effects after intraventricular administration. We have now proceeded to test its distribution in the ischemic brain, in order to determine how rapidly BMP-7 may diffuse through brain parenchyma. We also determined whether it has effects on expression of intermediate filaments in neurons short-term after the injury as a partial basis for its restorative activity. Finally we examined effects on motor behavior after stroke. Adult male Sprague-Dawley rats were subjected to a 60-minute occlusion of the right middle cerebral artery, and 24 hours thereafter, injections of BMP-7 or vehicle into the lateral ventricle on the ipsilateral side, at a dose of 25 ul (1 ug/ul), were performed. The animals were sacrificed 1, 3, 6, and 24 hours following the BMP-7 administration. In terms of localization in the brain parenchyma, we found that BMP-7 was mostly present in the ependyma 1 hour following injection, while it extended to a few adjacent neurons at 3 hours post-injection. However, the 6- and 24-hour groups both had significant BMP-7-immunoreactive labeling in neurons, primarily in the striatum and thalamus. Neurofilament expression appeared to be fairly weak on the injected side in animals that had received the vehicle injection, whereas a significant upregulation in neurofilament staining was observed at 6- and 24 hours post-injection of BMP-7. Significant neurite outgrowth, with obvious growth cones, was observed at 24 hours, particularly in the ventral striatum and accumbens. These results suggest that BMP-7 injection may aid in the expression of intermediate neuronal filaments following an ischemic injury, and furthermore that the injected factor can become incorporated into neurons located several millimeters from the lateral ventricle. Adult Sprague-Dawley rats were anesthetized with chloral hydrate. The middle cerebral artery (MCA) was transiently occluded by a filament, inserted through the right internal carotid artery. The filament was removed after 60-min ischemia to allow reperfusion. Some animals were killed 24 hours after MCA occlusion (MCAo) to examine BMP-7 mRNA expression. Other animals received a single dose of intravenous BMP-7 or vehicle at 24 hours after MCA occlusion and were used for subsequent behavioral studies and BMP-7 immunostaining. BMP-7 mRNA was upregulated 24 hours after MCAo in non-treated animals. BMP-7-immunoreactivity was dose-dependently increased on the ischemic side hippocampus/dentate on the 6th day after MCAo in animals receiving intravenous injection of BMP-7. Animals receiving BMP-7 also showed a decrease in body asymmetry from days 7 to day 14 and an increase in locomotor activity on day 14 after MCAo. Our data indicate that BMP-7, given parenterally after stroke, can pass through the blood brain barrier on the ischemic side and induce behavioral recovery in stroke animals at longer testing times.