Evidence map›Paper›PMID 41927845›Full record

ArticleScientific reports2026

Association of tear fluid glutathione synthetase and glutathione levels with amyloid positivity.

Nienke van de Sande, Saleh Ahmed, Ward van Deuse, Willemijn J Jansen, Anouk den Braber, Pieter Jelle Visser, Frans R J Verhey, Michelle Thach, Frank D Verbraak, Femke H Bouwman and 5 more

Abstract read
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In one paragraph

Article in Scientific reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

15 authors.

Nienke van de SandeUniversity Eye Clinic, Maastricht University Medical Center+, Maastricht, the Netherlands.
Saleh AhmedCenter for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA.
Ward van DeuseUniversity Eye Clinic, Maastricht University Medical Center+, Maastricht, the Netherlands.
Willemijn J JansenMental Health and Neuroscience Research Institute, Maastricht University, Maastricht, The Netherlands.
Anouk den BraberDepartment of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.
Pieter Jelle VisserMental Health and Neuroscience Research Institute, Maastricht University, Maastricht, The Netherlands.
Frans R J VerheyMental Health and Neuroscience Research Institute, Maastricht University, Maastricht, The Netherlands.
Michelle ThachAlzheimer Center Amsterdam, Department of Neurology, Amsterdam University Medical Center, Maastricht, Netherlands.
Frank D VerbraakOphthalmology Department, Amsterdam UMC Location VUmc, Amsterdam, Netherlands.
Femke H BouwmanAlzheimer Center Amsterdam, Department of Neurology, Amsterdam University Medical Center, Maastricht, Netherlands.
Rudy M M A NuijtsUniversity Eye Clinic, Maastricht University Medical Center+, Maastricht, the Netherlands.
Inez H G B RamakersMental Health and Neuroscience Research Institute, Maastricht University, Maastricht, The Netherlands.
Carroll A B WebersUniversity Eye Clinic, Maastricht University Medical Center+, Maastricht, the Netherlands.
Ashok SharmaCenter for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA.
Marlies GijsUniversity Eye Clinic, Maastricht University Medical Center+, Maastricht, the Netherlands. marlies.gijs@mumc.nl.

Funding

NWO (Dutch Research Council) Veni Fellowship 09150161810102
6 · The paper itself

Abstract

Tear fluid is a promising source of biomarkers for Alzheimer’s disease (AD). This study characterized the tear fluid proteome across AD and dementia stages. Tear fluid was collected from 60 participants, cognitively normal (CN) individuals (n = 32), patients with mild cognitive impairment (n = 14), and dementia (n = 14). Of these, 27 were amyloid PET-negative and 33 PET-positive. The proteome was analyzed using label-free mass spectrometry, followed by targeted validation immunoassays of key findings. In total, 703 proteins were reliably identified. A notable upregulated protein in dementia compared with CN was glutathione synthetase (GSS) (1.7-fold, p = 0.02). Validation revealed elevated GSS (2-fold) and its enzymatic product glutathione (1.7-fold) in tear fluid of amyloid PET–positive participants. Incorporating GSS and glutathione as pre-screeners could reduce the need for PET scans by up to 75%. Tear fluid shows promise as a non-invasive source for AD biomarkers, offering novel disease insights, and potential utility for pre-screening prior to PET imaging.

Indexed as

Alzheimer DiseaseAmyloidGlutathioneGlutathione SynthaseTearsAgedAged, 80 and overBiomarkersCognitive DysfunctionDementiaFemaleHumansMalePositron-Emission TomographyProteomeAmyloidBiomarkersGlutathioneGlutathione SynthaseProteomeAlzheimer’s diseaseamyloid PETBiomarkersDementiaDiagnosisGlutathione synthetaseImmunoassayProteomicsTear fluid

Identifiers

PMID41927845
PMCPMC13233852

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.