Activated Src kinases interact with the N-methyl-D-aspartate receptor after neonatal brain ischemia
Activated Src kinases interact with the N-methyl-D-aspartate receptor after neonatal brain ischemia
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DOI：
10.1002/ana.21365
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发表时间：
2008-05-01
影响因子：
11.2
通讯作者：
Ferriero, Donna M.
中科院分区：
文献类型：
--
作者：
Jiang, Xiangning;Mu, Dezhi;Ferriero, Donna M.
目的：新生儿脑卒中与n -甲基- d -天冬氨酸受体（NMDAR）介导的兴奋性毒性脑损伤有关。Src家族激酶（SFKs）被认为是NMDAR调控的分子中枢。我们确定了新生儿缺氧缺血（HI）后SFKs激活与NMDAR Lyrosine磷酸化之间的关系，并研究了选择性SFKs抑制剂PP2（4-氨基-5-（4-氯苯基）-7-（t-丁基）吡唑啉[3,4 -d]锥体啶）对新生儿脑缺血损伤的神经保护潜力。方法：采用Rice-Vannucci模型对出生第7天的CD1小鼠进行新生儿HI损伤。Western blot检测突触后密度SFKs活性。通过共免疫沉淀法确定NMDAR酪氨酸磷酸化及其与SFKs的关联。用PP2或其无活性类似物PP3处理的动物的大脑，用甲酚紫和铁染色进行组织学检查，以评估损伤程度。结果：新生儿HI导致NMDAR亚基NR2A和NR2B酪氨酸磷酸化快速和短暂增加。这种上调与Fyn和Src与NR2A和NR2B的增强关联相关。在HI后突触后密度中，SFKs被激活。PP2抑制SFKs可减轻新生儿HI后的脑损伤，而PP3不能保护大脑免受HI损伤。解释：SFKs可能在新生儿HI后nmdar介导的兴奋性毒性和导致神经元死亡的下游事件中发挥重要作用。抑制SFKs可能对新生儿中风提供保护。在发育中的大脑HI后，与其阻断NMDAR，不如在突触后密度上操纵NMDAR信号复合体的成分可能更安全、更有益。
Objective: Neonatal stroke is associated with the N-methyl-D-aspartate receptor (NMDAR)-mediated excitotoxic brain injury. Src family kinases (SFKs) are considered to be the molecular hub for NMDAR regulation. We determined the relationship between SFKs activation and NMDAR Lyrosine phosphorylation after neonatal hypoxia-ischemia (HI) and investigated the neuroprotective potential of a selective SFKs inhibitor, PP2 (4-amino-5-(4-chlorophenyl)-7-(t-butyl) pyrazolo [3, 4-d] pyramidine), against neonatal brain ischemic injury.Methods: The Rice-Vannucci model was adapted for neonatal HI injury in postnatal day 7 CD1 mice. SFKs activity in the postsynaptic densities was measured by Western blot. NMDAR tyrosine phosphorylation and their association with SFKs were determined by coimmunoprecipitation. Brains from animals treated with PP2 or its inactive analog, PP3, were examined histologically with cresyl violet and iron stain to assess the degree of damage.Results: Neonatal HI resulted in a rapid and transient increase in tyrosine phosphorylation of NMDAR subunits NR2A and NR2B. This upregulation correlated with the enhanced association of Fyn and Src with NR2A and NR2B. SFKs were activated in the postsynaptic densities after HI. Inhibition of SFKs with PP2 attenuated brain injury after neonatal HI, whereas PP3 did not protect the brain from the HI insult.Interpretation: SFKs may play an important role in NMDAR-mediated excitotoxicity and downstream events leading to neuronal death after neonatal HI. Inhibition of SFKs may provide protection against neonatal stroke. Rather than blockade of NMDAR after HI in the developing brain, it may be safer and more beneficial to manipulate components of the NMDAR signaling complex at the postsynaptic density.