Home › Research › Brain scans and imaging
Novel 18F-labeled arylquinoline derivatives for noninvasive imaging of tau pathology in Alzheimer disease
Okamura N, Furumoto S, Harada R, Tago T, Yoshikawa T, Fodero-Tavoletti M, Mulligan RS, Villemagne VL et al.. Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 2013-07-15
Topic: Disease mechanisms in lab and animal studies
Unlabelled Neurofibrillary tangles in Alzheimer disease (AD) brains are composed of the microtubule-associated protein tau. Noninvasive monitoring of tau protein aggregates in the living brain will provide useful information regarding tau pathophysiology in AD. However, no PET probes are currently available for selective detection of tau pathology in AD. We have previously reported (18)F-labeled THK-523 ((18)F-6-(2-fluoroethoxy)-2-(4-aminophenyl)quinoline) as a tau imaging radiotracer candidate for PET. After compound optimization, we developed novel (18)F-labeled arylquinoline derivatives, (18)F-THK-5105 and (18)F-THK-5117, for use as tau imaging PET tracers. Methods (18)F-labeled compounds were prepared from the corresponding tosylated precursors. The binding affinity of compounds to synthetic tau aggregates and tau-rich AD brain homogenates was determined by saturation and competition binding assays. The binding selectivity of compounds to tau pathology was evaluated by autoradiography of AD brain sections. The pharmacokinetics of compounds were assessed in biodistribution studies in normal mice. A 14-d toxicity study with intravenous administration of compounds was performed using rats and mice. Results In vitro binding assays demonstrated higher binding affinity of THK-5105 and THK-5117 than THK-523 to tau protein aggregates and tau-rich AD brain homogenates. Autoradiographic analyses of AD brain sections showed that these radiotracers preferentially bound to neurofibrillary tangles and neuropil threads, which colocalized with Gallyas-positive and immunoreactive tau protein deposits. The distribution of this radiotracer binding in AD brain sections was completely different from that of (11)C-Pittsburgh compound B, showing preferential binding to amyloid plaques. Furthermore, these derivatives demonstrated abundant initial brain uptake and faster clearance in normal mice than (18)F-THK-523 and other reported (18)F-labeled radiotracers. THK-5105 and THK-5117 showed no toxic effects related to the administration of these compounds in mice and rats and no significant binding for various neuroreceptors, ion channels, and transporters at 1-μM concentrations. Conclusion (18)F-labeled THK-5105 and THK-5117 are promising candidates as PET tau imaging radiotracers.
Key findings
- Results In vitro binding assays demonstrated higher binding affinity of THK-5105 and THK-5117 than THK-523 to tau protein aggregates and tau-rich AD brain homogenates.
- Autoradiographic analyses of AD brain sections showed that these radiotracers preferentially bound to neurofibrillary tangles and neuropil threads, which colocalized with Gallyas-positive and immunoreactive tau protein deposits.
- Furthermore, these derivatives demonstrated abundant initial brain uptake and faster clearance in normal mice than (18)F-THK-523 and other reported (18)F-labeled radiotracers.
- THK-5105 and THK-5117 showed no toxic effects related to the administration of these compounds in mice and rats and no significant binding for various neuroreceptors, ion channels, and transporters at 1-μM concentrations.
New to this subject? Start with our plain-English guide: Brain scans & tests →
Study details
- Evidence strengthLow
How this study scored 36/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 21 of the 58 points we could judge it on, which is 36 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Journal of nuclear medicine : official publication, Society of Nuclear Medicine) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2013 — within 20 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 23857514) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 21 / 58 | Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 21 of the 58 points we could judge it on is 36 out of 100. |
| Total | 36 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
Free copy unknown: no free-copy check has an answer for this record yet. That does not mean it is paywalled.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Okamura, N., Furumoto, S., Harada, R., Tago, T., Yoshikawa, T., Fodero-Tavoletti, M., et al. (2013). Novel 18F-labeled arylquinoline derivatives for noninvasive imaging of tau pathology in Alzheimer disease. Journal of nuclear medicine : official publication, Society of Nuclear Medicine. https://doi.org/10.2967/jnumed.112.117341
Vancouver
Okamura N, Furumoto S, Harada R, Tago T, Yoshikawa T, Fodero-Tavoletti M, et al. Novel 18F-labeled arylquinoline derivatives for noninvasive imaging of tau pathology in Alzheimer disease. Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2013. doi:10.2967/jnumed.112.117341. PMID: 23857514.
BibTeX
@article{okamura2013-23857514,
author = {Okamura, N. and Furumoto, S. and Harada, R. and Tago, T. and Yoshikawa, T. and Fodero-Tavoletti, M. and Mulligan, R. S. and Villemagne, V. L. and others},
title = {{Novel 18F-labeled arylquinoline derivatives for noninvasive imaging of tau pathology in Alzheimer disease}},
journal = {Journal of nuclear medicine : official publication, Society of Nuclear Medicine},
year = {2013},
doi = {10.2967/jnumed.112.117341},
pmid = {23857514},
url = {https://doi.org/10.2967/jnumed.112.117341}
}