Evidence map›Paper›PMID 41876924›Full record

ArticleClinical oral investigations2026

Periodontal inflammation and tryptophan-kynurenine metabolism in Parkinson's disease.

Melis Yilmaz, Aslihan Bakici, Rumeysa Parlat, İpek N Akpinar, Rabia Karaaslan, Nur Balci, Hilal Toygar, Şivge Kurgan, Muhittin A Serdar, Alpdoğan Kantarcı

Registry-linked trialAbstract read
In one paragraph

Article in Clinical oral investigations, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT07272564 (Periodontal Inflammation and Tryptophan-Kynurenine Metabolism in Parkinson's Disease), which is not on this 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.

NCT07272564 nacompletednot on this map

Periodontal Inflammation and Tryptophan-Kynurenine Metabolism in Parkinson's Disease

TypeinterventionalSponsorMedipol UniversityRan2022 to 2023Enrolled60ConditionsPeriodontal Diseases, InflammationArmsSaliva and serum sampling, Saliva, serum and GCF sampling
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

10 authors.

Melis YilmazDepartment of Periodontology, Faculty of Dentistry, Medipol University, İstanbul, Turkey.
Aslihan BakiciDepartment of Periodontology, Faculty of Dentistry, Medipol University, İstanbul, Turkey.
Rumeysa ParlatDepartment of Periodontology, Faculty of Dentistry, Medipol University, İstanbul, Turkey.
İpek N AkpinarDepartment of Periodontology, Faculty of Dentistry, Ankara University, Ankara, Turkey.
Rabia KaraaslanDepartment of Periodontology, Faculty of Dentistry, Ankara University, Ankara, Turkey.
Nur BalciDepartment of Periodontology, Faculty of Dentistry, Medipol University, İstanbul, Turkey.
Hilal ToygarDepartment of Periodontology, Faculty of Dentistry, Medipol University, İstanbul, Turkey.
Şivge KurganDepartment of Periodontology, Faculty of Dentistry, Ankara University, Ankara, Turkey.
Muhittin A SerdarDepartment of Medical Biochemistry, School of Medicine, Acibadem University, Ankara, Turkey.
Alpdoğan KantarcıSchool of Dental Medicine, Department of Developmental and SurgicalSciences, University of Minnesota, Minneapolis, MN, USA. kantarci@umn.edu.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveThe kynurenine pathway(KP) of tryptophan catabolism is a major regulator of the immune response. Metabolites of this pathway may have protective or degenerative effects on the nervous system. Based on our recent studies, we tested the hypothesis that KP metabolites play a role in the pathogenesis of the link between Parkinson’s disease (PAD) and Periodontitis (PD). MATERIALS AND

methodsSaliva and serum samples were collected from Stage III, Grade B periodontitis patients with PAD (Parkinson+periodontitis group, n = 20) and without PAD (periodontitis group, n = 24), and 24 periodontally and systemically healthy individuals (control group). Salivary and serum concentrations of tryptophan-kynurenine pathway metabolites, including tryptophan, kynurenine, kynurenine/tryptophan ratio, kynurenic acid, 3-hydroxykynurenine, picolinic acid, and quinolinic acid, were quantified using liquid chromatography–mass spectrometry. Periodontal status was assessed by recording plaque index, probing pocket depth, clinical attachment loss, and bleeding on probing according to standard clinical procedures.

resultsClinical parameters were significantly higher in the PD groups than in the control group (p < 0.001). The control group had the lowest BOP (3.54 ± 2.52), followed by the Parkinson+periodontitis (52.00 ± 14.91) and the periodontitis groups (70.46 ± 25.09). Salivary TRP, KYN, KYNA, PA, and QA levels were significantly higher in the Parkinson+periodontitis group than in the control. The salivary KYN/TRP ratio was significantly higher in the Parkinson+periodontitis group than in the other groups (p < 0.05). Serum TRP levels were significantly higher in the periodontitis group compared to the other groups. The serum KYN/TRP ratio was significantly higher in the Parkinson+ periodontitis group than in the control group (p < 0.05).

conclusionsThe data suggest that the metabolic regulation of immune responses via the tryptophan-kynurenine pathway may play a pathogenetic role in the link between Parkinson’s disease and periodontitis. CLINICAL RELEVANCE: Altered tryptophan–kynurenine metabolism in patients with both Parkinson’s disease and periodontitis suggests a shared inflammatory pathway linking the two conditions. Clinical Trials ID: NCT07272564.

Indexed as

KynurenineParkinson DiseasePeriodontitisTryptophanAgedChromatography, LiquidFemaleHumansMaleMass SpectrometryMiddle AgedSalivaKynurenineTryptophanInflammationKynurenine pathwayParkinson's diseasePeriodontitisTryptophan metabolism

Identifiers

PMID41876924
PMCPMC13013110

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

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.