Department of Neurosurgery, Stanford University School of Medicine, 1050 Arastradero Road, Building A, Palo Alto, CA 94304-1334, USA.
BioTime Inc., 1010 Atlantic Ave, Suite 102, Alameda, CA 94501-1147, USA.
Int J Mol Sci. 2018 Nov 28;19(12):3782. doi: 10.3390/ijms19123782.
Ischemic stroke is a leading cause of death and disability worldwide. Potential therapeutics aimed at neural repair and functional recovery are limited in their blood-brain barrier permeability and may exert systemic or off-target effects. We examined the effects of brain-derived neurotrophic factor (BDNF), delivered via an extended release HyStem-C hydrogel implant or vehicle, on sensorimotor function, infarct volume, and neuroinflammation, following permanent distal middle cerebral artery occlusion (dMCAo) in rats. Eight days following dMCAo or sham surgery, treatments were implanted directly into the infarction site. Rats received either vehicle, BDNF-only (0.167 µg/µL), hydrogel-only, hydrogel impregnated with 0.057 µg/µL of BDNF (hydrogel + BDNF), or hydrogel impregnated with 0.167 µg/µL of BDNF (hydrogel + BDNF). The adhesive removal test (ART) and 28-point Neuroscore (28-PN) were used to evaluate sensorimotor function up to two months post-ischemia. The hydrogel + BDNF group showed significant improvements on the ART six to eight weeks following treatment and their behavioral performance was consistently greater on the 28-PN. Infarct volume was reduced in rats treated with hydrogel + BDNF as were levels of microglial, phagocyte, and astrocyte marker immunoexpression in the corpus striatum. These data suggest that targeted intracerebral delivery of BDNF using hydrogels may mitigate ischemic brain injury and restore functional deficits by reducing neuroinflammation.
缺血性脑卒中是全球范围内导致死亡和残疾的主要原因。潜在的旨在神经修复和功能恢复的治疗方法在血脑屏障通透性方面存在局限性,并且可能发挥全身或非靶向作用。我们研究了脑源性神经营养因子(BDNF)通过延长释放 HyStem-C 水凝胶植入物或载体,对永久性大脑中动脉闭塞(dMCAo)后大鼠感觉运动功能、梗死体积和神经炎症的影响。在 dMCAo 或假手术后 8 天,将治疗物直接植入梗死部位。大鼠接受载体、BDNF 单独(0.167 µg/µL)、水凝胶单独、水凝胶中浸渍有 0.057 µg/µL 的 BDNF(水凝胶+BDNF)或水凝胶中浸渍有 0.167 µg/µL 的 BDNF(水凝胶+BDNF)。采用粘附物去除试验(ART)和 28 点神经评分(28-PN)评估缺血后长达两个月的感觉运动功能。在治疗后 6 至 8 周,水凝胶+BDNF 组在 ART 上的表现显著改善,其行为表现始终在 28-PN 上更高。在接受水凝胶+BDNF 治疗的大鼠中,梗死体积减少,纹状体中的小胶质细胞、吞噬细胞和星形胶质细胞标志物免疫表达水平降低。这些数据表明,使用水凝胶进行靶向脑内 BDNF 传递可能通过减少神经炎症来减轻缺血性脑损伤并恢复功能缺陷。