中国神经再生研究(英文版) ›› 2023, Vol. 18 ›› Issue (6): 1300-1307.doi: 10.4103/1673-5374.358607

• 原著:退行性病与再生 • 上一篇    下一篇

阿尔茨海默病病理过程中Aβ沉积、鞘磷脂水平与P-糖蛋白表达和功能的关系

  

  • 出版日期:2023-06-15 发布日期:2023-01-05
  • 基金资助:
    国家重点研究与发展计划(2021yfc2701800;2021YFC2701805)和复旦大学基因工程国家重点实验室开放研究基金(SKLGE-2119)

The relationship among amyloid-β deposition, sphingomyelin level, and the expression and function of P-glycoprotein in Alzheimer’s disease pathological process

Zi-Kang Xing1, Li-Sha Du1, Xin Fang1, Heng Liang1, Sheng-Nan Zhang1, Lei Shi1, Chun-Xiang Kuang2, Tian-Xiong Han3, Qing Yang1, *   

  1. 1State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, Shanghai, China; 2Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai, China; 3Department of Traditional Chinese Medicine, Tenth People’s Hospital of Tongji University, Shanghai, China
  • Online:2023-06-15 Published:2023-01-05
  • Contact: Qing Yang, PhD, yangqing68@fudan.edu.cn.
  • Supported by:
    This work was supported by the National Key Research and Development Program of China, Nos. 2021YFC2701800 and 2021YFC2701805 (to QY) and Open Research Fund of State Key Laboratory of Genetic Engineering, Fudan University, No. SKLGE-2119 (to TXH and QY).

摘要:

在阿尔茨海默病中,转运体P-糖蛋白(P-gp)负责清除大脑中的淀粉样β蛋白(Aβ),Aβ似乎与鞘磷脂的代谢有关,而鞘磷脂参与P-糖蛋白的调节。有必要阐明P-糖蛋白和鞘磷脂随Aβ的变化,并阐明它们在阿尔茨海默病的病理过程中的潜在联系。实验首先使用了不同月龄的APP/PS1 阿尔茨海默病模型小鼠研究P-糖蛋白在阿尔茨海默病病理过程中的变化。发现WT和APP/PS1小鼠脑内P-糖蛋白的表达均随年龄的增长而增加,而3月龄和6月龄的APP/PS1小鼠的P-糖蛋白转运活性与WT小鼠相近,在9月龄时高于WT小鼠,在12月龄时显著低于WT小鼠。这可能是由于在9月龄时,Aβ沉积快速增加,导致APP/PS1小鼠脑中P-糖蛋白表达和功能代偿性地上调。在12月龄时,Aβ的过度沉积导致APP/PS1小鼠的P-糖蛋白表达上调,但清除Aβ的能力受损,转运活性降低。同时研究了鞘磷脂在阿尔茨海默病病理过程中的变化。发现9和12月龄的APP/PS1小鼠大脑中的鞘磷脂水平显著低于WT小鼠,神经酰胺水平和中性鞘磷脂酶1活性显著高于WT小鼠。之后,使用hCMEC/D3细胞人血脑屏障模型,使用不同浓度的Aβ处理细胞模拟不同的病理状态,发现了类似的结果:较高浓度的Aβ处理(5 和10 μM)上调中性鞘磷脂酶1的表达和活性,导致P-糖蛋白表达提高,但转运活性下降。说明在严重的阿尔茨海默病病理状态下,无论是高浓度Aβ处理的hCMEC/D3细胞,还是月龄较大的阿尔茨海默病后期APP/PS1小鼠,Aβ的积累都会导致中性鞘磷脂酶1的表达和活性上调,P-糖蛋白的转运功能受损。实验通过体外和体内结果共同揭示了阿尔茨海默病中P-糖蛋白、鞘磷脂和Aβ之间的关系,证明中性鞘磷脂酶1通过鞘磷脂/神经酰胺途径调节P-糖蛋白的表达和功能,为阿尔茨海默病治疗和药物开发提供了新策略。

https://orcid.org/0000-0003-4162-922X (Qing Yang)

Abstract: In Alzheimer’s disease, the transporter P-glycoprotein is responsible for the clearance of amyloid-β in the brain. Amyloid-β correlates with the sphingomyelin metabolism, and sphingomyelin participates in the regulation of P-glycoprotein. The amyloid cascade hypothesis describes amyloid-β as the central cause of Alzheimer’s disease neuropathology. Better understanding of the change of P-glycoprotein and sphingomyelin along with amyloid-β and their potential association in the pathological process of Alzheimer’s disease is critical. Herein, we found that the expression of P-glycoprotein in APP/PS1 mice tended to increase with age and was significantly higher at 9 and 12 months of age than that in wild-type mice at comparable age. The functionality of P-glycoprotein of APP/PS1 mice did not change with age but was significantly lower than that of wild-type mice at 12 months of age. Decreased sphingomyelin levels, increased ceramide levels, and the increased expression and activity of neutral sphingomyelinase 1 were observed in APP/PS1 mice at 9 and 12 months of age compared with the levels in wild-type mice. Similar results were observed in the Alzheimer’s disease mouse model induced by intracerebroventricular injection of amyloid-β1–42 and human cerebral microvascular endothelial cells treated with amyloid-β1–42. In human cerebral microvascular endothelial cells, neutral sphingomyelinase 1 inhibitor interfered with the changes of sphingomyelin metabolism and P-glycoprotein expression and functionality caused by amyloid-β1–42 treatment. Neutral sphingomyelinase 1 regulated the expression and functionality of P-glycoprotein and the levels of sphingomyelin and ceramide. Together, these findings indicate that neutral sphingomyelinase 1 regulates the expression and function of P-glycoprotein via the sphingomyelin/ceramide pathway. These studies may serve as new pursuits for the development of anti-Alzheimer’s disease drugs.

Key words: Alzheimer’s disease, amyloid-β, APP/PS1 mice, ceramide, ezrin-radixin-moesin, human cerebral microvascular endothelial cells, neutral sphingomyelinase 1, P-glycoprotein, sphingomyelin synthase, sphingomyelin