Bemelmans Alexis-Pierre, Husson Isabelle, Jaquet Muriel, Mallet Jacques, Kosofsky Barry E, Gressens Pierre
CNRS, UMR 7091, Bâtiment CERVI, Hôpital de la Pitié-Salpétrière, Paris, France.
J Neurosci Res. 2006 Jan;83(1):50-60. doi: 10.1002/jnr.20704.
Excitotoxicity may be a critical factor in the formation of brain lesions associated with cerebral palsy. When injected into the murine neopallium at postnatal day 5, the glutamatergic analog N-methyl-D-aspartate (NMDA) produces transcortical neuronal death and periventricular white matter cysts, which mimic brain damage observed in human term and preterm neonates at risk for developing cerebral palsy. We previously showed that intracerebral injection of brain-derived neurotrophic factor (BDNF) was neuroprotective in this model. Because BDNF does not easily cross the blood-brain barrier, alternative strategies to avoid repeated intracerebral injections of BDNF should be tested, particularly when the goal of such translational research is ultimately to achieve clinical application. The goal of the present study was to assess the protective role of lentiviral-mediated gene transfer of BDNF against excitotoxic lesions induced by NMDA in newborn mice. We first assessed the biological activity of BDNF gene transfer in vitro and determined the efficiency of gene transfer in our in vivo model. We next administered the BDNF-expressing vector by intracerebral injection in neonatal mice, 3 days before inducing NMDA lesions. When compared with a control green fluorescent protein-expressing lentiviral vector, administration of BDNF-expressing vector induced a significant protection of the periventricular white matter and cortical plate against the NMDA-mediated insult. Intraventricular delivery of the BDNF-expressing lentiviral vector was more efficient in terms of neuroprotection than the intraparenchymal route. Altogether, the present study shows that viral-mediated gene transfer of BDNF to newborn mouse brain is feasible and affords significant neuroprotection against an excitotoxic insult.
兴奋性毒性可能是与脑瘫相关的脑损伤形成的关键因素。在出生后第5天将谷氨酸能类似物N-甲基-D-天冬氨酸（NMDA）注射到小鼠新皮层时，会导致跨皮质神经元死亡和脑室周围白质囊肿，这与有患脑瘫风险的足月和早产新生儿中观察到的脑损伤相似。我们之前表明，在此模型中脑内注射脑源性神经营养因子（BDNF）具有神经保护作用。由于BDNF不易穿过血脑屏障，应测试避免重复脑内注射BDNF的替代策略，特别是当此类转化研究的目标最终是实现临床应用时。本研究的目的是评估慢病毒介导的BDNF基因转移对新生小鼠中NMDA诱导的兴奋性毒性损伤的保护作用。我们首先在体外评估了BDNF基因转移的生物学活性，并确定了我们体内模型中的基因转移效率。接下来，在诱导NMDA损伤前3天，通过脑内注射将表达BDNF的载体给予新生小鼠。与表达对照绿色荧光蛋白的慢病毒载体相比，给予表达BDNF的载体可显著保护脑室周围白质和皮质板免受NMDA介导的损伤。就神经保护而言，脑室内递送表达BDNF的慢病毒载体比脑实质内途径更有效。总之，本研究表明，将BDNF通过病毒介导的基因转移至新生小鼠脑内是可行的，并且对兴奋性毒性损伤具有显著的神经保护作用。
