{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T11:53:49Z","timestamp":1777895629191,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T00:00:00Z","timestamp":1757030400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Buddhist Tzu Chi Medical Foundation","award":["TCRD111-048"],"award-info":[{"award-number":["TCRD111-048"]}]},{"name":"Buddhist Tzu Chi Medical Foundation","award":["TCMF-A 106-01-08"],"award-info":[{"award-number":["TCMF-A 106-01-08"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Indoxyl sulfate (IS), a gut microbiota-derived metabolite of tryptophan, is implicated in vascular dysfunction through oxidative stress and inflammation. This study evaluated the association between serum IS levels and aortic stiffness (AS) in patients with type 2 diabetes mellitus (T2DM). Materials and Methods: This cross-sectional study enrolled 80 patients with T2DM from a medical center in eastern Taiwan, excluding patients with malignancy, acute infection, heart failure, or recent cardiovascular events. Serum IS concentrations were quantified using liquid chromatography\u2013mass spectrometry. AS was assessed using carotid\u2013femoral pulse wave velocity (cfPWV), with values &gt; 10 m\/s indicating AS. Results: A total of 30 patients (37.5%) had AS. IS levels were significantly higher in the AS group than in the control group (p &lt; 0.001). After multivariate adjustment, IS remained an independent predictor of AS (odds ratio: 2.565, 95% confidence interval: 1.145\u20135.748, p = 0.022). Linear regression analysis confirmed IS as an independent contributor to cfPWV values (\u03b2 = 0.261, p = 0.019). Receiver operating characteristic analysis showed fair discriminatory ability (area under the curve = 0.739, p &lt; 0.001). Conclusions: In patients with T2DM, serum IS is an independent predictor of AS and may serve as a promising nontraditional biomarker for cardiovascular risk stratification.<\/jats:p>","DOI":"10.3390\/medicina61091607","type":"journal-article","created":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T12:18:18Z","timestamp":1757074698000},"page":"1607","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Serum Indoxyl Sulfate as a Potential Biomarker of Aortic Stiffness in Persons with Type 2 Diabetes Mellitus"],"prefix":"10.3390","volume":"61","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3021-0979","authenticated-orcid":false,"given":"I-Min","family":"Su","sequence":"first","affiliation":[{"name":"Department of Anesthesiology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi 62247, Taiwan"},{"name":"School of Medicine, Tzu Chi University, Hualien 97004, Taiwan"},{"name":"Institute of Medical Sciences, Tzu Chi University, Hualien 97004, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi-Yen","family":"Teng","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97004, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jer-Chuan","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97004, Taiwan"},{"name":"Division of Metabolism and Endocrinology, Buddhist Tzu Chi General Hospital, Hualien 97004, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8144-9146","authenticated-orcid":false,"given":"Chin-Hung","family":"Liu","sequence":"additional","affiliation":[{"name":"Graduate Institute of Clinical Pharmacy, School of Medicine, Tzu Chi University, Hualien 97004, Taiwan"},{"name":"School of Pharmacy, Tzu Chi University, Hualien 97004, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Du-An","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Medicine, Tzu Chi University, Hualien 97004, Taiwan"},{"name":"Department of Internal Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97004, Taiwan"},{"name":"Division of Metabolism and Endocrinology, Buddhist Tzu Chi General Hospital, Hualien 97004, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9364-4558","authenticated-orcid":false,"given":"Bang-Gee","family":"Hsu","sequence":"additional","affiliation":[{"name":"School of Medicine, Tzu Chi University, Hualien 97004, Taiwan"},{"name":"Institute of Medical Sciences, Tzu Chi University, Hualien 97004, Taiwan"},{"name":"Department of Internal Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97004, Taiwan"},{"name":"Division of Nephrology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97004, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1097\/XCE.0000000000000210","article-title":"Estimating life years lost to diabetes: Outcomes from analysis of National Diabetes Audit and Office of National Statistics data","volume":"9","author":"Heald","year":"2020","journal-title":"Cardiovasc. 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