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- Mackey, Scott, et al.
(författare)
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Direct intranigral administration of an ubiquitin proteasome system inhibitor in rat: Behavior, positron emission tomography, immunohistochemistry
- 2013
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Ingår i: Experimental Neurology. - : Elsevier BV. - 0014-4886. ; 247, s. 19-24
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Tidskriftsartikel (refereegranskat)abstract
- Several independent lines of research suggest that disruption of the ubiquitin proteasome system (UPS) may play a role in the pathophysiology of Parkinson's disease. Direct intracerebral injection of UPS inhibitors (e.g. lactacystin) in animals has consistently produced important features of the disease. In this study, a range of lactacystin doses (0.5, 1, 2, 10 and 20 mu g) were injected into the right substantia nigra in rats to determine the ideal dose required to produce a robust and specific lesion of the dopamine nigro-striatal system and motor deficits. Motor behavior, assessed with the tapered ledged beam task, was severely affected in animals that received high doses (10 and 20 mu g) but only mild, impairments were observed in animals that received low doses (0.5, I, and 2 mu g). Positron emission tomography was performed with a dedicated small animal scanner on the rats following the injection of the radio-labeled tracer (+/-)[C-11]dihydrotetrabenazine (DTBZ) which labels vesicular monoamine transporter type 2. Severe loss of [C-11]DTBZ binding in the ipsilateral striatum was observed in the higher dose groups and mild loss was observed in the low dose groups. Stereological cell counting of tyrosine hydroxylase immunoreactive cells in the substantia nigra and the ventral tegmental area indicated a dose dependent loss of dopaminergic neurons. Significant correlations were found between the behavioral motor deficits, striatal [C-11]DTBZ binding and cell counts of tyrosine hydroxylase immunoreactive cells. Taken together these results indicate that intranigral injection of lactacystin produces dose dependent effects on the dopamine nigro-striatal system and a dose of 10 mu g will produce a consistent severe lesion. Published by Elsevier Inc.
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| 2. |
- Perez-Soriano, Alexandra, et al.
(författare)
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PBB3 Imaging in Parkinsonian disorders: Evidence for binding to abnormally aggregated proteins in addition to tau proteins
- 2017
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Ingår i: Movement Disorders. - : Wiley. - 1531-8257 .- 0885-3185. ; 32:Suppl 2, s. 585-587
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Konferensbidrag (refereegranskat)abstract
- Objective: To study selective regional binding for tau pathology in vivo, using PET with [11C]PBB3 ([11C]methylamino pyridin-3-yl buta-1,3-dienyl benzo[d]thiazol-6-ol) in tauopathies, and in conditions not typically associated with tauopathy. Background: Tau imaging is a promising tool to study the link between tau and neurodegeneration. The specificity of tracers in vivo however remains uncertain, and off target binding is frequently present, limiting its use in parkinsonian disorders. Methods: Dynamic PET scans were obtained for 70 min after the bolus injection of [11C]PBB3 (mean dose 518.97MBq) in five PSP subjects, 1 subject with DCTN1 mutation and PSP phenotype,3 asymptomatic SNCA duplication carriers, 1 MSA subject, and 7 healthy controls of similar age. The occipital cortex was used as reference region for the PSP , the DCTN1 mutation and the MSA subjects. The cerebellar white matter was used as a reference region for the SNCA duplication carriers. Tissue reference Logan analysis was applied to each region of interest (ROI) using the appropriate reference region. Results: In PSP subjects, the highest retention of [11C]PBB3 was observed in putamen, midbrain, globus pallidus and substantia nigra. Longer disease duration and more advanced clinical severity were generally associated with higher tracer retention. The DCTN1/PSP phenotype case showed increased binding in putamen, parietal lobe, and globus pallidus. In SNCA duplication carriers there was a significant increase of [11C] PBB3 binding compared to controls in globus pallidus, putamen, thalamus, ventral striatum, substantia nigra, and pedunculopontine nucleus. The MSA case showed increased binding in comparison to the control group in frontal lobe, globus pallidus, midbrain, parietal lobe, putamen, temporal lobe, substantia nigra, thalamus and ventral striatum. Conclusions: All PSP patients showed increased retention of the tracer in the basal ganglia, as clinically expected. However, binding was also present in asymptomatic SNCA duplication carriers as well as the subject with MSA, which are not typically associated with pathological tau deposition. This suggests the possibility that [11C]PBB3 binds to alpha-synuclein or other proteins involved in neurodegeneration.
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| 3. |
- Perez-Soriano, Alexandra, et al.
(författare)
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PBB3 imaging in Parkinsonian disorders : Evidence for binding to tau and other proteins
- 2017
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Ingår i: Movement Disorders. - : Wiley. - 0885-3185. ; 32:7, s. 1016-1024
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND OBJECTIVES: To study selective regional binding for tau pathology in vivo, using PET with [(11) C]PBB3 in PSP patients, and other conditions not typically associated with tauopathy.METHODS: Dynamic PET scans were obtained for 70 minutes after the bolus injection of [(11) C]PBB3 in 5 PSP subjects, 1 subject with DCTN1 mutation and PSP phenotype, 3 asymptomatic SNCA duplication carriers, 1 MSA subject, and 6 healthy controls of similar age. Tissue reference Logan analysis was applied to each region of interest using a cerebellar white matter reference region.RESULTS: In comparison to the control group, PSP subjects showed specific uptake of [(11) C]PBB3 in putamen, midbrain, GP, and SN. Longer disease duration and more advanced clinical severity were generally associated with higher tracer retention. A DCTN1/PSP phenotype case showed increased binding in putamen, parietal lobe, and GP. In SNCA duplication carriers, there was a significant increase of [(11) C] PBB3 binding in GP, putamen, thalamus, ventral striatum, SN, and pedunculopontine nucleus. The MSA case showed increased binding in frontal lobe, GP, midbrain, parietal lobe, putamen, temporal lobe, SN, thalamus, and ventral striatum.CONCLUSIONS: All PSP patients showed increased retention of the tracer in the basal ganglia, as expected. Binding was also present in asymptomatic SNCA duplication carriers and in an MSA case, which are not typically associated with pathological tau deposition. This suggests the possibility that [(11) C]PBB3 binds to alpha-synuclein. © 2017 International Parkinson and Movement Disorder Society.
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