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Translocator protein (18 kDa) positron emission tomography imaging as a biomarker of neuroinflammation in epilepsy

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Abstract

Increasing evidence indicate that neuroinflammation triggered by glial cells plays a significant role in epileptogenesis. To this effect, the overexpression of translocator protein 18 kDa (TSPO) in activated microglia and astrocytes has been identified as an inflammatory biomarker in epilepsy. It is now possible to quantify neuroinflammation using non-invasive positron emission tomography (PET) imaging of TSPO. With the advancement of radiotracers, TSPO PET has become an innovative tool in elucidating the "neuroinflammatory machinery" of drug-resistant epilepsy. Furthermore, TSPO PET has demonstrated potential in detecting MRI-negative epileptogenic zones (EZ) and provided an innovative perspective in epileptic medical treatment. This manuscript presents a comprehensive exploration of the neuroinflammatory mechanisms of epilepsy, alongside a thorough review of TSPO PET studies conducted in clinical and preclinical settings. The primary objective is to deepen our understanding of epilepsy progression and to establish TSPO PET as an effective monitoring tool for treatment efficacy.

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Data Availability

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

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Acknowledgements

We are grateful for funding from National Key Research and Development Program of China, Grant No. 2022YFC2503804, from National Natural Science Foundation of China, Grant Nos. 82071461, 82271503, and from Natural Science Foundation of Hunan Province, Grant No. 2021JJ31060. We further thank anonymous reviewers for constructive feedback.

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Authors and Affiliations

  1. Department of Neurology, National Clinical Research Center for Geriatric Disorders, **angya Hospital, Central South University, Changsha, 410008, Hunan, China

    Li Qin, Haoyue Zhu, Yangsa Du & Li Feng

  2. Department of Nuclear Medicine, **angya Hospital, Central South University, Changsha, 410008, Hunan, China

    Ling **ao & Yongxiang Tang

  3. National Clinical Research Center for Geriatric Disorders, **angya Hospital, Central South University, Changsha, 410008, Hunan, China

    Li Feng

  4. Department of Neurology, **angya Hospital, Central South University (Jiangxi Branch), Nanchang, 330000, Jiangxi, China

    Li Feng

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Qin, L., **ao, L., Zhu, H. et al. Translocator protein (18 kDa) positron emission tomography imaging as a biomarker of neuroinflammation in epilepsy. Neurol Sci (2024). https://doi.org/10.1007/s10072-024-07648-9

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