Long-term consequences of human alpha-synuclein overexpression in the primate ventral midbrain
Long-term consequences of human alpha-synuclein overexpression in the primate ventral midbrain
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DOI：
10.1093/brain/awl382
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发表时间：
2007-03-01
期刊：
影响因子：
14.5
通讯作者：
Kirik, Deniz
中科院分区：
文献类型：
--
作者：
Eslamboli, Andisheh;Romero-Ramos, Marina;Kirik, Deniz
利用重组腺相关病毒（rAAV）载体过表达人a-突触核蛋白（α -syn），为研究帕金森病和其他突触核蛋白病的神经退行性过程提供了一种新的工具。我们使用伪型rAAV2/5载体在灵长类动物腹侧中脑中表达人类野生型(wt) α -syn、A53T突变α -syn或绿色荧光蛋白（GFP）。24只成年普通狨猴（Callithrix jacchus）在转导后进行了1年的定期行为测试。α -syn过表达影响运动行为，使所有动物至少在9周内保持无症状，然后在15至27周期间，在表达wt- α -syn的动物中发现了包括头部位置偏差和全身旋转在内的运动偏差；在后期，过度表达A53T α -syn的动物表现出逐渐恶化的运动表现，运动协调错误增加。过表达wt或A53T α -syn的动物的组织学分析显示纹状体中多巴胺能纤维明显变性。然而，在腹侧中脑，多巴胺能神经变性在A53T组中比在WT组中更为突出，这表明这两种蛋白质在灵长类动物大脑中的毒性不同。在黑质中存活的细胞体及其过程被针对病理形式的α -syn的抗体染色，该α -syn在Ser位置129磷酸化。此外，我们首次在灵长类动物中脑中发现了α -syn过表达后含有泛素的聚集体。脑梗少突胶质细胞也有不同程度的损失。这些组织学和行为学数据表明，该模型为研究多巴胺能系统的进行性神经变性和α -syn和泛素的沉积提供了独特的机会，类似于帕金森病，并为神经保护策略测试新的治疗靶点。
Overexpression of human a-synuclein (alpha-syn) using recombinant adeno-associated viral (rAAV) vectors provides a novel tool to study neurodegenerative processes seen in Parkinson's disease and other synucleinopathies. We used a pseudotyped rAAV2/5 vector to express human wild-type (wt) alpha-syn, A53T mutated alpha-syn, or the green fluorescent protein (GFP) in the primate ventral midbrain. Twenty-four adult common marmosets (Callithrix jacchus) were followed with regular behavioural tests for 1 year after transduction. alpha-Syn overexpression affected motor behaviour such that all animals remained asymptomatic for at least 9 weeks, then motor bias comprising head position bias and full body rotations were seen in wt-alpha-syn expressing animals between 15 and 27 weeks; in the later phase, the animals overexpressing the A53T alpha-syn, in particular, showed a gradual worsening of motor performance, with increased motor coordination errors. Histological analysis from animals overexpressing either the wt or A53T alpha-syn showed prominent degeneration of dopaminergic fibres in the striatum. In the ventral midbrain, however, the dopaminergic neurodegeneration was more prominent in the A53T group than in the WT group suggesting differential toxicity of these two proteins in the primate brain. The surviving cell bodies and their processes in the substantia nigra were stained by antibodies to the pathological form of alpha-syn that is phosphorylated at Ser position 129. Moreover, we found, for the first time, ubiquitin containing aggregates after overexpression of alpha-syn in the primate midbrain. There was also a variable loss of oligodendroglial cells in the cerebral peduncle. These histological and behavioural data suggest that this model provides unique opportunities to study progressive neurodegeneration in the dopaminergic system and deposition of alpha-syn and ubiquitin similar to that seen in Parkinson's disease, and to test novel therapeutic targets for neuroprotective strategies.