Effect of early psychosine accumulation in Krabbe Disease on CNS progenitor cells

描述（由申请人提供）：在原发性中枢神经系统（CNS）祖细胞群体中，特别是那些负责适当髓鞘形成的少突胶质谱系中，尚未研究克拉布病早期精神素积累的分子效应。当早发克拉布病患者出现神经系统症状时，由于早期异常水平的精神素积累及其在关键发育时期对脆弱祖细胞群体的影响，对中枢神经系统的损害可能是不可修复的。初步数据表明，生理上相关浓度的精神碱激活了原代少突胶质细胞/ 2型星形胶质细胞祖细胞（O-2A/OPCs）中的[13]氧化还原/Fyn/c-Cbl通路。该通路在正常O-2A/OPC增殖和迁移中起重要作用。对这一途径的进一步研究将更好地确定精神毒素毒性的细胞和分子机制。此外，fda批准的药物将在NINDS II文库中进行筛选，以确定哪些药物可以改善或加剧精神病的毒性作用。快速体外筛选将使用自动贴壁细胞计数系统进行。候选药物将在早发性克拉伯病小鼠模型，抽搐小鼠中进一步进行体内测试。发育影响将通过脑和脊髓切片的免疫组织化学染色和Western blot分析来确定。行为和运动功能测试，寿命和症状严重程度将作为药物治疗的功能读数进行。目的是通过药物治疗干预，保护早发Krabbe患者的早期中枢神经系统发育免受内源性精神素积累的影响，最终在与基因和酶替代疗法联合使用时提高疗效。

DESCRIPTION (provided by applicant): The molecular effect of early psychosine accumulation in Krabbe disease has not been studied in primary central nervous system (CNS) progenitor cell populations, specifically those of the oligodendroglial lineage responsible for proper myelination. By the time early onset Krabbe disease patients have presented with neurological symptoms, damage to the CNS may be irreparable due to early accumulation of abnormal levels of psychosine and its effect on vulnerable progenitor populations during critical developmental periods. Preliminary data suggests that physiologically relevant concentrations of psychosine are activating the previously described [13] redox/Fyn/c-Cbl pathway in primary oligodendrocyte/type-2 astrocyte progenitor cells (O-2A/OPCs). This pathway plays an important role in normal O-2A/OPC proliferation and migration. Further investigations on this pathway will better define cellular and molecular mechanisms of psychosine toxicity. Moreover, FDA-approved drugs in the NINDS II library will be screened to identify those that either ameliorate or exacerbate the toxic effects of psychosine. Rapid in vitro screening will be conducted using an automated adherent cell cytometry system. Candidate drugs will be further tested in vivo in the early onset Krabbe disease mouse model, the twitcher mouse. Developmental effects will be identified through immunohistochemical staining of brain and spinal cord sections and Western blot analysis. Behavioral and motor function tests, lifespan and symptom severity will be conducted as functional readouts of drug treatment. The goal is to protect early CNS development from effects of endogenous psychosine accumulation in early onset Krabbe patients through drug treatment intervention, ultimately to enable increased efficacy when used in combination with genetic and enzymatic replacement therapies.