中国神经再生研究(英文版) ›› 2025, Vol. 20 ›› Issue (4): 1090-1091.doi: 10.4103/NRR.NRR-D-24-00246

• 观点:退行性病与再生 • 上一篇    下一篇

转运体蛋白与神经退行性变:阿尔茨海默病的启示

  

  • 出版日期:2025-04-15 发布日期:2024-07-01

Translocator protein and neurodegeneration: insights from Alzheimer’s disease

Arpit Kumar Pradhan* , Rainer Rupprecht, Gerhard Rammes   

  1. Klinik für Anaesthesiologie und Intensivmedizin der Technischen Universität München, Klinikum rechts der Isar, Munich, Germany (Pradhan AK, Rammes G)
    Graduate School of Systemic Neurosciences, Ludwig-Maximilians-Universität München, Martinsried, Germany (Pradhan AK)
    Department of Psychiatry and Psychotherapy, University Regensburg, Regensburg, Germany (Rupprecht R)
  • Online:2025-04-15 Published:2024-07-01
  • Contact: Arpit Kumar Pradhan, PhD,arpitgudu@gmail.com.
  • Supported by:
    This work was supported by the German Research Foundation (Deutsche Forschungsgemeinschaft) (DFG), project number 422179811 to RR and RA 689/12-1 to GR.

摘要: https://orcid.org/0000-0003-4047-7615 (Arpit Kumar Pradhan)

Abstract:

The 18 kDa translocator protein (TSPO) located on the outer mitochondrial membrane regulates several key cellular processes including mitochondrial homeostasis, cholesterol transport, apoptosis, cell proliferation, and maintenance of mitochondrial health (Rupprecht et al., 2022, 2023). TSPO is expressed in both peripheral organs and the central nervous system, with a more pronounced expression in tissues that produce steroids. The main reason why TSPO has garnered so much attention is because it plays a key role in neurosteroidogenesis by transferring cholesterol from the outer to the inner mitochondrial membrane, which is the rate-limiting step in neurosteroid synthesis. A cholesterol-recognizing amino acid consensus domain has been identified in the cytosolic C terminus of the TSPO protein by both in vitro and site-directed mutagenesis experiments (Li et al., 2001). However, the role of TSPO in the process of neurosteroid synthesis has been challenged by several studies, particularly TSPO knockout models, which suggest that TSPO removal does not affect the phenotype or the system’s viability (Tu et al., 2014). However, ligands targeting TSPO have been shown to enhance levels of neurosteroids which suggests that neurosteroidogenesis is one of the major functional roles mediated by the TSPO protein. It is interesting to note that several polymorphisms have been identified in the TSPO gene and studied in humans. Among these, the rs6971 polymorphism has been shown to alter the TSPO-ligand binding affinity (Nutma et al., 2021). Furthermore, this polymorphism is recognized for its role in decreasing pregnenolone and adrenocorticotropic hormone-induced corticosteroid levels, which may contribute to the progression of bipolar disorders (Nutma et al., 2021).