神经元中的构成性内分泌体穿孔允许通过内部化预先形成的纤维来诱导α-Synuclein聚合
Anwesha Sanyal1,2, Gustavo Scanavachi1,2, Elliott Somerville2
1Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA.
bioRxiv : the preprint server for biology
|January 23, 2024
概括
神经元具有自然穿孔的内分泌体,在帕金森病模型中促进α-synuclein聚合和细胞死亡. 抑制PIKfyve激酶可以减少这些穿孔,并防止疾病的进展.
科学领域:
- 细胞生物学 细胞生物学
- 神经科学是一个神经科学.
- 病理学 病理学 病理学
背景情况:
- 内细胞通路对于细胞吸收至关重要,但可以被病原体和有毒聚合物利用.
- 阿尔法-同核素 (α-syn) 聚合和细胞间传播是帕金森病 (PD) 的标志.
- 内化α-syn预形成纤维素 (PFFs) 可以诱导神经元死亡,特别是在特定的神经元模型中.
研究的目的:
- 在人类诱导的神经元模型 (iNs) 中研究PFF诱导的神经元死亡的机制.
- 识别促进α-syn聚合的神经元中的细胞漏洞.
- 探索同核蛋白病变的潜在治疗点.
主要方法:
- 利用了人类诱导的多能干细胞衍生神经元 (iN) 和父母的iPSC.
- 采用生物传感器的活细胞光学显微镜来检测内溶酶体受伤.
- 应用体积聚焦离子束扫描电子显微镜 (FIB-SEM) 进行超结构分析.
- 研究了PIKfyve激酶抑制 (Apilimod,Vacuolin-1) 对α-syn聚合和神经元死亡的影响.
主要成果:
- 在INs中,晚期内分体和溶解体的一个子集表现出自发的穿孔,与父母iPSC或非神经元细胞不同.
- 这些穿孔,通过FIB-SEM在NN和小鼠神经元中观察到,与类似纳米孔的损伤有关.
- 抑制PIKfyve激酶显著降低了PFF诱导的α-syn聚合和iN死亡,尽管继续吸收PFF.
结论:
- 神经元具有内在穿孔的内分泌体,作为细胞质α-syn与内化PFF相互作用的主要入口点.
- 这种内在的脆弱性是启动神经元中有毒α-syn聚合的关键因素.
- PIKfyve激酶抑制是一种有前途的治疗策略,通过稳定内分泌体膜来抵消同核蛋白病变.
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