{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T13:12:28Z","timestamp":1782306748816,"version":"3.54.5"},"reference-count":57,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T00:00:00Z","timestamp":1767571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bulgarian Ministry of Education and Science under the National Program \u201cYoung Scientists and Postdoctoral Students\u20132\u201d"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Chronic kidney disease (CKD) is associated with chronic inflammation and metabolic dysregulation. While endothelin-1 (ET-1) has been extensively studied, the role of endothelin-2 (ET-2) in CKD remains poorly understood. This cross-sectional study included 76 participants, 12 healthy controls and 64 CKD patients, stratified into three groups based on estimated glomerular filtration rate (eGFR): Group 1 (eGFR \u2265 90 mL\/min\/1.73 m2), Group 2 (eGFR 45\u201389 mL\/min\/1.73 m2), and Group 3 (eGFR 15\u201344 mL\/min\/1.73 m2). Serum concentrations of ET-1, ET-2, ET-3, uric acid (UA), and inflammatory markers (hsCRP and IL-6) were measured. ET-2 levels were significantly higher in the advanced CKD group (median 24.49 pg\/mL) compared to controls (median 19.32 pg\/mL; p = 0.030). No significant differences were observed for ET-1 or ET-3 across groups. ET-2 levels positively correlated with UA (rho = 0.243, p = 0.036), hsCRP (rho = 0.241, p = 0.039), and IL-6 (rho = 0.244, p = 0.038). These findings suggest that ET-2 may represent a potential biomarker reflecting metabolic and inflammatory dysregulation in CKD and highlight its possible relevance in disease severity assessment.<\/jats:p>","DOI":"10.3390\/ijms27010540","type":"journal-article","created":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T13:35:47Z","timestamp":1767620147000},"page":"540","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Endothelin-2 and Its Association with Uric Acid Levels and Systemic Inflammation: Relevance to Chronic Kidney Disease Progression"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0092-9488","authenticated-orcid":false,"given":"Alexander Bozhidarov","family":"Blazhev","sequence":"first","affiliation":[{"name":"Department of Biology, Medical University\u2014Pleven, 1 Kliment Ohridski Str., 5800 Pleven, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2464-353X","authenticated-orcid":false,"given":"Krasimir","family":"Kostov","sequence":"additional","affiliation":[{"name":"Department of Physiology and Pathophysiology, Medical University\u2014Pleven, 1 Kliment Ohridski Str., 5800 Pleven, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0325-6162","authenticated-orcid":false,"given":"Borislav Ivanov","family":"Ignatov","sequence":"additional","affiliation":[{"name":"Department of Physiology and Pathophysiology, Medical University\u2014Pleven, 1 Kliment Ohridski Str., 5800 Pleven, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tsvetelina","family":"Eftimova","sequence":"additional","affiliation":[{"name":"Hemodialysis Unit, St. Marina Hospital, 5800 Pleven, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2307-1229","authenticated-orcid":false,"given":"Tatyana Nedkova","family":"Simeonova","sequence":"additional","affiliation":[{"name":"Department of Physiology and Pathophysiology, Medical University\u2014Pleven, 1 Kliment Ohridski Str., 5800 Pleven, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6870-941X","authenticated-orcid":false,"given":"Svetla Ognyanova","family":"Blazheva","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory, Allergology and Clinical Immunology, Medical University\u2014Pleven, 5800 Pleven, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1038\/s41581-024-00820-6","article-title":"Chronic kidney disease and the global public health agenda: An international consensus","volume":"20","author":"Francis","year":"2024","journal-title":"Nat. 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