Department of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Wulumuqi Zhong Rd, Shanghai 200040, China.
Neurochem Res. 2012 Sep;37(9):2025-32. doi: 10.1007/s11064-012-0823-0. Epub 2012 Jun 17.
Accumulation of α-synuclein (α-Syn) is a common pathology for both familiar and sporadic Parkinson's disease (PD), enhancing its clearance might be a promising strategy for treating PD. To assess the potential of trehalose in this regard, we investigated its effect on the PC12 cells overexpressing wild type (WT) or A53T mutant α-Syn and the implicated pathway it might mediated. We observed that trehalose promoted the clearance of A53T α-Syn but not WT α-Syn in PC12 cells, and confirmed the increased LC3 and Lysotracker RED positive autolysosomes by using lysotracker and LC3 staining, the enhanced expression of LC3-II in Western blot, and more autophagosomes under Transmission Electron Microscope in a dose dependent manner after the trehalose treatment. The activation of autophagy can be alleviated by applying macroautophagy inhibitor 3-methyladenine (3-MA). In addition, degradation of A53T and WT α-Syn was blocked after Ubiquitin Proteasome System (UPS) inhibitor (MG132) was applied in those PC12 cells overexpressing A53T or WT α-Syn, suggesting that A53T α-Syn could be degraded by both UPS and macroautophagy. But the effect of trehalose on A53T α-Syn is mainly mediated through the macroautophagy pathway, which is not a dominant way for WT α-Syn clearance. Further in vivo research will be needed to verify the effectiveness of trehalose in treating PD.
α-突触核蛋白（α-Syn）的积累是家族性和散发性帕金森病（PD）的共同病理学特征，增强其清除可能是治疗 PD 的一种有前途的策略。为了评估海藻糖在这方面的潜力，我们研究了它对过表达野生型（WT）或 A53T 突变型 α-Syn 的 PC12 细胞的影响及其可能介导的途径。我们观察到，海藻糖促进了 A53T α-Syn 的清除，但不能促进 WT α-Syn 的清除，并且通过使用溶酶体追踪和 LC3 染色、Western blot 中 LC3-II 的增强表达以及透射电子显微镜下更多的自噬体，证实了溶酶体追踪和 LC3 染色，Western blot 中 LC3-II 的增强表达以及透射电子显微镜下更多的自噬体在剂量依赖性方式下，在海藻糖处理后，自噬体的清除增加。自噬的激活可以通过应用巨自噬抑制剂 3-甲基腺嘌呤（3-MA）来缓解。此外，在用泛素蛋白酶体系统（UPS）抑制剂（MG132）处理过表达 A53T 或 WT α-Syn 的 PC12 细胞后，A53T 和 WT α-Syn 的降解被阻断，这表明 A53T α-Syn 可以通过 UPS 和巨自噬途径降解。但海藻糖对 A53T α-Syn 的作用主要是通过巨自噬途径介导的，而不是 WT α-Syn 清除的主要途径。需要进一步的体内研究来验证海藻糖在治疗 PD 中的有效性。
