School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands; Department of Pediatrics, Maastricht University Medical Center+, Maastricht, The Netherlands.
Exp Neurol. 2013 Dec;250:293-303. doi: 10.1016/j.expneurol.2013.09.026. Epub 2013 Oct 8.
Hypoxic-ischemic encephalopathy (HIE) is common in preterm infants, but currently no curative therapy is available. Cell-based therapy has a great potential in the treatment of hypoxic-ischemic preterm brain injury. Granulocyte-colony stimulating factor (G-CSF) is known to mobilize endogenous hematopoietic stem cells (HSC) and promotes proliferation of endogenous neural stem cells. On these grounds, we hypothesized that systemic G-CSF would be neuroprotective in a large translational animal model of hypoxic-ischemic injury in the preterm brain. Global hypoxia-ischemia (HI) was induced by transient umbilical cord occlusion in instrumented preterm sheep. G-CSF treatment (100μg/kg intravenously, during five consecutive days) was started one day before the global HI insult to ascertain mobilization of endogenous stem cells within the acute phase after global HI. Mobilization of HSC and neutrophils was studied by flow cytometry. Brain sections were stained for microglia (IBA-1), myelin basic protein (MBP) and myeloperoxidase (MPO) to study microglial proliferation, white matter injury and neutrophil invasion respectively. Electrographic seizure activity was analyzed using amplitude-integrated electroencephalogram (aEEG). G-CSF effectively mobilized CD34-positive HSC in the preterm sheep. In addition, G-CSF caused marked mobilization of neutrophils, but did not influence enhanced invasion of neutrophils into the preterm brain after global HI. Microglial proliferation and hypomyelination following global HI were reduced as a result of G-CSF treatment. G-CSF did not cause a reduction of the electrographic seizure activity after global HI. In conclusion, G-CSF induced mobilization of endogenous stem cells which was associated with modulation of the cerebral inflammatory response and reduced white matter injury in an ovine model of preterm brain injury after global HI. G-CSF treatment did not improve neuronal function as shown by seizure analysis. Our study shows that G-CSF treatment has neuroprotective potential following hypoxic-ischemic injury in the preterm brain.
缺氧缺血性脑病（HIE）在早产儿中很常见，但目前尚无有效的治疗方法。细胞疗法在治疗缺氧缺血性早产儿脑损伤方面具有巨大潜力。粒细胞集落刺激因子（G-CSF）可动员内源性造血干细胞（HSC）并促进内源性神经干细胞增殖。基于这些原因，我们假设全身 G-CSF 在缺氧缺血性损伤的大型转化动物模型中对早产儿脑具有神经保护作用。通过仪器化的早产羊脐带短暂结扎诱导全脑缺氧缺血（HI）。在全脑 HI 损伤前一天开始 G-CSF 治疗（100μg/kg 静脉内，连续 5 天），以确定在全脑 HI 后急性期内动员内源性干细胞。通过流式细胞术研究 HSC 和中性粒细胞的动员。用小胶质细胞（IBA-1）、髓鞘碱性蛋白（MBP）和髓过氧化物酶（MPO）染色脑切片，分别研究小胶质细胞增殖、白质损伤和中性粒细胞浸润。使用振幅整合脑电图（aEEG）分析电发作活动。G-CSF 可有效动员早产羊的 CD34 阳性 HSC。此外，G-CSF 导致中性粒细胞明显动员，但不会影响全脑 HI 后中性粒细胞侵入早产儿脑。全脑 HI 后 G-CSF 治疗可减少小胶质细胞增殖和少突胶质细胞脱髓鞘。G-CSF 不会导致全脑 HI 后电发作活动减少。总之，G-CSF 诱导内源性干细胞动员，与调节大脑炎症反应和减少全脑 HI 后早产儿脑白质损伤有关。如癫痫分析所示，G-CSF 治疗并未改善神经元功能。我们的研究表明，G-CSF 治疗在早产儿脑缺氧缺血性损伤后具有神经保护潜力。
