title: Translocator Protein-18 kDa (TSPO) Positron Emission Tomography (PET) Imaging and Its Clinical Impact in Neurodegenerative Diseases.
abstract: In vivo exploration of activated microglia in neurodegenerative diseases is achievable by Positron Emission Tomography (PET) imaging, using dedicated radiopharmaceuticals targeting the translocator protein-18 kDa (TSPO). In this review, we emphasized the major advances made over the last 20 years, thanks to TSPO PET imaging, to define the pathophysiological implication of microglia activation and neuroinflammation in neurodegenerative diseases, including Parkinson's disease, Huntington's disease, dementia, amyotrophic lateral sclerosis, multiple sclerosis, and also in psychiatric disorders. The extent and upregulation of TSPO as a molecular biomarker of activated microglia in the human brain is now widely documented in these pathologies, but its significance, and especially its protective or deleterious action regarding the disease's stage, remains under debate. Thus, we exposed new and plausible suggestions to enhance the contribution of TSPO PET imaging for biomedical research by exploring microglia's role and interactions with other cells in brain parenchyma. Multiplex approaches, associating TSPO PET radiopharmaceuticals with other biomarkers (PET imaging of cellular metabolism, neurotransmission or abnormal protein aggregates, but also other imaging modalities, and peripheral cytokine levels measurement and/or metabolomics analysis) was considered. Finally, the actual clinical impact of TSPO PET imaging as a routine biomarker of neuroinflammation was put into perspective regarding the current development of diagnostic and therapeutic strategies for neurodegenerative diseases.
authors.affiliation: CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France. ac.dupont@chu-tours.fr.|Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France. ac.dupont@chu-tours.fr.
authors.forename: Anne-Claire
authors.initials: AC
authors.lastname: Dupont
authors.affiliation: CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France. berenger.largeau@etu.univ-tours.fr.
authors.forename: Bérenger
authors.initials: B
authors.lastname: Largeau
authors.affiliation: CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France. maria.ribeiro@univ-tours.fr.|Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France. maria.ribeiro@univ-tours.fr.
authors.forename: Maria Joao
authors.initials: MJ
authors.lastname: Santiago Ribeiro
authors.affiliation: CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France. denis.guilloteau@univ-tours.fr.|Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France. denis.guilloteau@univ-tours.fr.
authors.forename: Denis
authors.initials: D
authors.lastname: Guilloteau
authors.affiliation: Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France. claire.tronel@univ-tours.fr.
authors.forename: Claire
authors.initials: C
authors.lastname: Tronel
authors.affiliation: CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France. nicolas.arlicot@univ-tours.fr.|Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France. nicolas.arlicot@univ-tours.fr.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Arlicot
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D042241:Early Diagnosis; D006801:Humans; D017628:Microglia / Q000378:metabolism; D019636:Neurodegenerative Diseases / Q000000981:diagnostic imaging* / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000494:pharmacology*; D018079:Receptors, GABA / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D019275:Radiopharmaceuticals; D018079:Receptors, GABA; C499229:TSPO protein, human
keywords: PET; TSPO; microglial activation; neurodegenerative diseases; neuroinflammation; psychiatric disorders; radiopharmaceutical