Evaluation of 18F-IAM6067 as a sigma-1 receptor PET tracer for neurodegeneration in vivo in rodents and in human tissue
| Autor: | Michael Green, Marie-Claude Asselin, Inga B. Fricke, Marco Mottinelli, Andreas H. Jacobs, Christopher R. McCurdy, Hervé Boutin, Andrew C Robinson, Michael Kassiou, David M. A. Mann, Samuel D. Banister, Matthias Vandesquille, Elizabeth Barnett, Christophe Mesangeau, Christian Prenant, Francois-Xavier Lepelletier |
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| Rok vydání: | 2020 |
| Předmět: |
Male
0301 basic medicine Fluorine Radioisotopes Parkinson's disease Medicine (miscellaneous) PET radiotracer Striatum 0302 clinical medicine Positron Emission Tomography Computed Tomography Pharmacology Toxicology and Pharmaceutics (miscellaneous) Aged 80 and over biology Chemistry Neurodegeneration Brain Human brain Middle Aged Alzheimer's disease Molecular Imaging Globus pallidus medicine.anatomical_structure Female medicine.symptom Research Paper medicine.medical_specialty Substantia nigra AMPA receptor Lesion 03 medical and health sciences Alzheimer Disease Internal medicine medicine Animals Humans Receptors sigma Animal model Parkinson Disease Secondary Rats Wistar Oxidopamine Aged animal model medicine.disease Rats Disease Models Animal 030104 developmental biology Endocrinology nervous system biology.protein Autoradiography Sigma 1 receptor Radiopharmaceuticals NeuN 030217 neurology & neurosurgery |
| Zdroj: | Theranostics Lepelletier, F-X, Vandesquille, M, Asselin, M-C, Prenant, C, Robinson, A, Mann, D, Green, M, Barnett, E, Banister, S D, Mottinelli, M, Mesangeau, C, McCurdy, C R, Fricke, I, Jacobs, A H, Kassiou, M & Boutin, H 2020, ' Evaluation of 18F-IAM6067 as a sigma-1 receptor PET tracer for neurodegeneration in vivo in rodents and in human tissue ', Theranostics, pp. 7938-7955 . https://doi.org/10.7150/thno.47585 Lepelletier, F-X, Vandesquille, M, Asselin, M-C, Prenant, C, Robinson, A C, Mann, D M A, Green, M, Barnett, E, Banister, S D, Mottinelli, M, Mesangeau, C, McCurdy, C R, Fricke, I B, Jacobs, A H, Kassiou, M & Boutin, H 2020, ' Evaluation of F-18-IAM6067 as a sigma-1 receptor PET tracer for neurodegeneration in vivo in rodents and in human tissue ', Theranostics, vol. 10, no. 18, pp. 7938-7955 . https://doi.org/10.7150/thno.47585 |
| ISSN: | 1838-7640 |
| Popis: | The sigma 1 receptor (S1R) is widely expressed in the CNS and is mainly located on the endoplasmic reticulum. The S1R is involved in the regulation of many neurotransmission systems and, indirectly, in neurodegenerative diseases. The S1R may therefore represent an interesting neuronal biomarker in neurodegenerative diseases such as Parkinson's (PD) or Alzheimer's diseases (AD). Here we present the characterisation of the S1R-specific 18F-labelled tracer 18F-IAM6067 in two animal models and in human brain tissue. Methods: Wistar rats were used for PET-CT imaging (60 min dynamic acquisition) and metabolite analysis (1, 2, 5, 10, 20, 60 min post-injection). To verify in vivo selectivity, haloperidol, BD1047 (S1R ligand), CM398 (S2R ligand) and SB206553 (5HT2B/C antagonist) were administrated for pre-saturation studies. Excitotoxic lesions induced by intra-striatal injection of AMPA were also imaged by 18F-IAM6067 PET-CT to test the sensitivity of the methods in a well-established model of neuronal loss. Tracer brain uptake was also verified by autoradiography in rats and in a mouse model of PD (intrastriatal 6-hydroxydopamine (6-OHDA) unilateral lesion). Finally, human cortical binding was investigated by autoradiography in three groups of subjects (control subjects with Braak ≤2, and AD patients, Braak >2 & ≤4 and Braak >4 stages). Results: We demonstrate that despite rapid peripheral metabolism of 18F-IAM6067, radiolabelled metabolites were hardly detected in brain samples. Brain uptake of 18F-IAM6067 showed differences in S1R anatomical distribution, namely from high to low uptake: pons-raphe, thalamus medio-dorsal, substantia nigra, hypothalamus, cerebellum, cortical areas and striatum. Pre-saturation studies showed 79-90% blockade of the binding in all areas of the brain indicated above except with the 5HT2B/C antagonist SB206553 and S2R ligand CM398 which induced no significant blockade, indicating good specificity of 18F-IAM6067 for S1Rs. No difference between ipsi- and contralateral sides of the brain in the mouse model of PD was detected. AMPA lesion induced a significant 69% decrease in 18F-IAM6067 uptake in the globus pallidus matching the neuronal loss as measured by NeuN, but only a trend to decrease (-16%) in the caudate putamen despite a significant 91% decrease in neuronal count. Moreover, no difference in the human cortical binding was shown between AD groups and controls. Conclusion: This work shows that 18F-IAM6067 is a specific and selective S1R radiotracer. The absence or small changes in S1R detected here in animal models and human tissue warrants further investigations and suggests that S1R might not be the anticipated ideal biomarker for neuronal loss in neurodegenerative diseases such as AD and PD. |
| Databáze: | OpenAIRE |
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