Development of low-molecular-weight compound therapy for polyglutamine diseases

在这项研究中，我们阐明了成人发病的运动神经元疾病的病理生理学，并开发了基于发病机制的治疗方法。使用抗聚谷氨酰胺抗体1C2的免疫组织化学方法表明，突变AR的弥散性核积累远比NIs更频繁和广泛，分布在广泛的中枢神经系统核中，并且在更多的内脏器官中，比目前认为的要多。此外，突变AR在脊髓运动神经元的弥漫性核积累程度与CAG重复长度密切相关。因此，突变AR的弥漫性核积累显然是SBMA神经变性的主要发病机制。解剖标本中阴囊皮肤上皮细胞中AR突变体的积累程度与脊髓运动神经元中AR突变体的积累程度倾向于相关，且与CAG重复长度呈良好相关，与运动功能量表呈负相关。在一项随机双盲试验中，LHRH类似物治疗抑制突变AR蛋白在阴囊皮肤的积累，降低血清肌酸激酶水平，改善SBMA患者的吞咽功能。对于肌萎缩性侧索硬化症（ALS），我们证实了valosin-containing protein （VCP）直接与修饰ALS发病机制的蛋白Dorfin结合，并且VCP ATPase活性对Dorfin的E3活性有深远的影响。采用微阵列技术结合激光显微解剖技术，对散发性渐冻人尸体中分离的退行性脊髓运动神经元的基因表达谱进行了检测。下调的基因包括与细胞骨架/轴突运输、转录和细胞表面抗原/受体相关的基因。相反，细胞死亡相关基因大多上调。

In this study, we elucidated the pathophysiology of adult-onset motor neuron diseases, and developed pathogenesis-based therapy for them. Immunohistochemically using 1C2, an anti-polyglutamine antibody, demonstrated that diffuse nuclear accumulation of mutant AR was far more frequent and extensive than NIs being distributed in a wide array of CNS nuclei, and in more visceral organs than thus far believed. Furthermore, the extent of diffuse nuclear accumulation of mutant AR in spinal motor neurons was closely related to CAG repeat length. Thus, diffuse nuclear accumulation of mutant AR apparently is a cardinal pathogenesis underlying neurodegeneration in SBMA. The degree of mutant AR accumulation in scrotal skin epithelial cells tended to be correlated with that in the spinal motor neurons in autopsy specimens, and it was well correlated with CAG repeat length and inversely correlated with the motor functional scale. In a randomized double-blind trial, LHRH analog treatment inhibited mutant AR protein accumulation in the scrotal skin, reduced serum level of creatine kinase, and improved the swallowing function of SBMA patients.As for amyotrophic lateral sclerosis (ALS), we calrified that valosin-containing protein (VCP) directly binds to Dorfin, a protein modifying ALS pathogenesis, and that VCP ATPase activity profoundly contributes to the E3 activity of Dorfin. Using microarray technology combined with laser-captured microdissection, gene expression profiles of degenerating spinal motor neurons isolated from autopsied patients with sporadic ALS were examined. Downregulated genes included those associated with cytoskeleton/axonal transport, transcription, and cell surface antigens/receptors. In contrast, cell death-associated genes were mostly upregulated.