Evidence mapPaperPMID 41382255Full record

ArticleEndocrinology and metabolism (Seoul, Korea)2026

Higher Circulating Kynurenine Levels Linked to Higher Risk of Sarcopenia in Older Adults: A Cohort Study and UK Biobank Analysis.

June Yeon Kim, Yunju Jo, So Jeong Park, Ji Yeon Baek, Geonyoung Jang, Eunju Lee, Hyuk Sakong, Su Jung Kim, Sung-Jin Kim, Dongryeol Ryu and 2 more

Abstract read
In one paragraph

Article in Endocrinology and metabolism (Seoul, Korea), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing 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

1 citing paper in PubMed.

  1. Review
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

12 authors.

June Yeon Kim *Department of Oral Histology and Developmental Biology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea.
Yunju Jo *Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Korea.
So Jeong Park *Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Ji Yeon BaekDivision of Geriatrics, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Geonyoung JangDivision of Geriatrics, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Eunju LeeDivision of Geriatrics, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Hyuk SakongAsan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Su Jung KimDepartment of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Sung-Jin KimDepartment of Oral Histology and Developmental Biology, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea.
Dongryeol RyuDepartment of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Korea. dryu@gist.ac.kr.
Hyun Ju YooDepartment of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. yoohyunju@amc.seoul.kr.
Beom-Jun KimDivision of Endocrinology and Metabolism, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. umkbj0825@amc.seoul.kr.

Funding

Asan Institute for Life Sciences, Asan Medical Center 2022IP0036Korea Health Industry Development Institute RS-2024-00507256Korean Endocrine Society of KESMinistry of Health and Welfare RS-2024-00401934Ministry of Science and ICT RS-2023-NR077276National Research Foundation of Korea RS-2024-00399341
6 · The paper itself

Abstract

backgruoundWhile experimental studies show kynurenine, a tryptophan metabolite, drives muscle catabolism through pro-oxidative and inflammatory mechanisms, clinical evidence linking circulating kynurenine to sarcopenia in humans remains scarce.

methodsIn a cross-sectional study of 165 community-dwelling older adults, sarcopenia was diagnosed using Asian-specific criteria and serum kynurenine levels were measured by liquid chromatography-tandem mass spectrometry. Using UK Biobank datasets, plasma indoleamine 2,3-dioxygenase 1 (IDO1)-the enzyme converting tryptophan to kynurenine-was quantified via Olink proteomics, and Mendelian randomization was used to assess the causal effect of plasma IDO1 on sarcopenia risk based on genomewide association study data.

resultsIn multivariable adjusted analyses, older adults with sarcopenia, low muscle mass, or weak muscle strength had 21.3%-29.2% higher serum kynurenine concentrations than controls (P<0.001 to 0.010). Circulating kynurenine levels were inversely correlated with skeletal muscle index and grip strength (P=0.001 and 0.022, respectively). Each standard deviation increase in serum kynurenine was associated with a 1.80-2.97-fold increased risk for sarcopenia-related outcomes (P<0.001 to 0.010). In the UK Biobank, higher IDO1 activity was associated with reduced muscle mass and strength (P=0.007 and P=0.004, respectively), and Mendelian randomization indicated a significant causal relationship between plasma IDO1 levels and increased sarcopenia risk (P= 0.010, β=0.105).

conclusionThese findings extend previous experimental evidence to the clinical setting, suggesting that elevated kynurenine-driven by IDO1 activity-contributes to sarcopenia in older adults. Circulating kynurenine may serve as an exploratory biomarker candidate for identifying individuals at heightened risk for muscle deterioration, warranting further validation in future studies.

Indexed as

BiomarkersKynurenineSarcopeniaAgedBiological Specimen BanksCohort StudiesCross-Sectional StudiesFemaleHumansIndoleamine-Pyrrole 2,3,-DioxygenaseMaleRisk FactorsUK BiobankUnited KingdomBiomarkersIDO1 protein, humanIndoleamine-Pyrrole 2,3,-DioxygenaseKynurenineBiomarkersIndoleamine 2,3-dioxygenase 1KynurenineSarcopenia

Identifiers

PMID41382255
PMCPMC13341186

What Socratic holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

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 Socratic graph.