| 1. |
- Forsberg, A., et al.
(författare)
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Disease activity in rheumatoid arthritis is inversely related to cerebral TSPO binding assessed by [C-11]PBR28 positron emission tomography
- 2019
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Ingår i: Journal of Neuroimmunology. - : Elsevier BV. - 0165-5728 .- 1872-8421. ; 334
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Tidskriftsartikel (refereegranskat)abstract
- Reumatoid Arthritis (RA) is an autoimmune disorder characterized by peripheral joint inflammation. Recently, an engagement of the brain immune system has been proposed. The aim with the current investigation was to study the glial cell activation marker translocator protein (TSPO) in a well characterized cohort of RA patients and to relate it to disease activity, peripheral markers of inflammation and autonomic activity. Fifteen RA patients and fifteen healthy controls matched for age, sex and TSPO genotype (rs6971) were included in the study. TSPO was measured using Positron emission tomography (PET) and the radioligand [C-11] PBR28. The outcome measure was total distribution volume (V-T) estimated using Logan graphical analysis, with grey matter (GM) as the primary region of interest. Additional regions of interest analyses as well as voxel-wise analyses were also performed. Clinical evaluation of disease activity, symptom assessments, serum analyses of cytokines and heart rate variability (HRV) analysis of 24 h ambulatory ECG were performed in all subjects. There were no statistically significant group differences in TSPO binding, either when using the primary outcome V-T or when normalizing V-T to the lateral occipital cortex (p > 0.05). RA patients had numerically lower V-T values than healthy controls (Cohen's D for GM = -0.21). In the RA group, there was a strong negative correlation between [C-11]PBR28 V-T in GM and disease activity (DAS28)(r = -0.745, p = 0.002, corrected for rs6971 genotype). Higher serum levels of IFN gamma and TNF-alpha were found in RA patients compared to controls (p < 0.05) and several measures of autonomic activity showed significant differences between RA and controls (p < 0.05). However, no associations between markers of systemic inflammation or autonomic activity and cerebral TSPO binding were found. In conclusion, no statistically significant group differences in TSPO binding as measured with [C-11]PBR28 PET were detected. Within the RA group, lower cerebral TSPO binding was associated with higher disease activity, suggesting that cerebral TSPO expression may be related to disease modifying mechanisms in RA. In light of the earlier confirmed neuro-immune features of RA, these results warrant further investigations regarding neuro-immune joint-to-CNS signalling to open up for potentially new treatment strategies.
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| 2. |
- Johnson, Allan E., et al.
(författare)
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AZD2184: a radioligand for sensitive detection of beta-amyloid deposits
- 2009
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Ingår i: Journal of Neurochemistry. - : Wiley. - 0022-3042 .- 1471-4159. ; 108:5, s. 1177-1186
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Tidskriftsartikel (refereegranskat)abstract
- The presence of beta-amyloid plaques in brain is a hallmark of Alzheimer's disease (AD) and serves as a biomarker for confirmation of diagnosis postmortem. Positron emission tomography (PET) radioligands such as Pittsburgh compound B ([(11)C]-2-(3-fluoro-4-methylamino-phenyl)-benzothiazol-6-ol) (PIB) binds selectively to beta-amyloid and are promising new tools supporting the clinical diagnoses of AD. In addition, such methodology may be useful for evaluation of new drugs aiming at reduction of amyloid plaque load. The objective of this study is to develop a new amyloid selective PET radioligand with higher signal-to-background ratio when compared with existing amyloid PET ligands. The lead compound, AZD2184, (2-[6-(methylamino)pyridin-3-yl]-1,3-benzothiazol-6-ol) was found to have high affinity for amyloid fibrils in vitro (K(d): 8.4 +/- 1.0 nM). Two minutes after i.v. administration in rats, about 1% of the dose was in brain. In vitro autoradiography on cortical brain sections from amyloid-beta precursor protein/presenilin 1 (APP/PS1) mice and AD patients showed that while [(3)H]AZD2184 and [(3)H]PIB are mutually displaceable, [(3)H]AZD2184 displays a higher signal-to-background ratio primarily by virtue of lower background binding levels. The ratio of binding ability in prefrontal cortex (high plaque load) to subcortical white matter (background) was 4.5 for [(3)H]AZD2184 and 0.8 for [(3)H]PIB at 1 nM. In adjacent cortical sections from APP/PS1 mouse as well as from AD cortical tissue, [(3)H]AZD2184 and antibodies to human beta-amyloid labeled identical structures. In vivo administration of [(3)H]AZD2184 to APP/PS1 mice further showed that [(3)H]AZD2184 labels amyloid deposits with low non-specific background binding. Taken together, the pre-clinical profile of AZD2184 in relation to the reference ligand PIB, suggests that (11)C-labeled AZD2184 is a potential radioligand for PET-visualization of beta-amyloid deposits in the living human brain.
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| 3. |
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| 4. |
- Larsson, Maria, et al.
(författare)
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Age-related loss of olfactory sensitivity : Association to dopamine transporter binding in putamen
- 2009
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Ingår i: Neuroscience. - : Elsevier Ltd.. - 0306-4522 .- 1873-7544. ; 161:2, s. 422-426
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Tidskriftsartikel (refereegranskat)abstract
- The relationship between age-related reductions in the binding potential for the striatal dopamine transporter (DAT) and age-related deficits in olfactory sensitivity was examined in 12 subjects ranging from 36 to 82 years of age. Positron emission tomography (PET) and the radioligand [11C]β-CIT-FE were used to determine DAT binding in two striatal regions, the caudate and the putamen. The results showed age-related losses of DAT binding from early to late adulthood of similar size for caudate and putamen, and there was a pronounced age deterioration in olfactory sensitivity. Importantly, the age-related olfactory deficit was associated with reductions in DAT binding in putamen, but not caudate. Also, DAT binding in putamen added systematic variance in odor threshold after controlling for age. The findings indicate that DAT binding in putamen is related to age-related olfactory deficits, as well as to odor sensitivity independently of age.
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