{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T12:08:16Z","timestamp":1767960496736,"version":"3.49.0"},"reference-count":58,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T00:00:00Z","timestamp":1767916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Secretar\u00eda de Educaci\u00f3n, Ciencia, Tecnolog\u00eda e Innovaci\u00f3n (SECTEI) de la Ciudad de M\u00e9xico","award":["SECTEI\/158\/2024"],"award-info":[{"award-number":["SECTEI\/158\/2024"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: Obesity is characterized by chronic low-grade inflammation and metabolic disturbances, including an altered tryptophan (Trp) catabolism through the kynurenine pathway (KP). Since the KP is closely linked to immune activity, energy metabolism, and hepatic function, modulating its flux through lifestyle interventions has gained interest as a potential therapeutic strategy. Objective: This exploratory study aimed to investigate the impact of a structured 12-week weight loss program (WLP) on serum KP metabolites in a sample of Mexican women with obesity. Methods: This study involved a pre\u2013post-intervention design conducted in twenty-four women with clinically diagnosed obesity from the Mexican Navy who underwent a structured 12-week weight loss program combining a hypocaloric diet with moderate-intensity aerobic exercise; no control group was included. Anthropometric parameters, serum biochemistry, and circulating levels of Trp, kynurenine (KYN), kynurenic acid (KYNA), and 3-hydroxykynurenine (3-HK) were assessed before and after intervention. Psychological assessments of anxiety and depression were also conducted in a subset of participants. Results: The WLP significantly reduced body weight, BMI, fat mass, fasting insulin, and C-reactive protein levels. Serum concentrations of Trp, KYN, and KYNA decreased, while 3-HK showed a non-significant upward trend. Enzymatic indexes revealed a significant increase in the 3-HK\/KYN ratio and a decrease in the KYNA\/3-HK ratio, suggesting a shift toward kynurenine monooxygenase (KMO) branch. Notably, higher KYNA-related ratios were inversely associated with depressive symptoms. Conclusions: These findings position the KP as a responsive metabolic interface potentially linking improvements in body composition, liver function, and psychological status during structured weight loss efforts.<\/jats:p>","DOI":"10.3390\/nu18020211","type":"journal-article","created":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T10:35:52Z","timestamp":1767954952000},"page":"211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Modulation of the Kynurenine Pathway in Obese Mexican Navy Women Following a Structured Weight Loss Program: A Pre\u2013Post-Intervention Study"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4268-2279","authenticated-orcid":false,"given":"Laura","family":"S\u00e1nchez-Chapul","sequence":"first","affiliation":[{"name":"Neuromuscular Diseases Laboratory, Clinical Neurosciences Division, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8610-7404","authenticated-orcid":false,"given":"Daniela","family":"Ram\u00edrez-Ortega","sequence":"additional","affiliation":[{"name":"Neurobiochemistry and Behavior Laboratory, National Institute of Neurology and Neurosurgery \u201cManuel Velasco Su\u00e1rez\u201d, Mexico City 14269, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6121-0675","authenticated-orcid":false,"given":"Mar\u00eda Alejandra","family":"Samudio-Cruz","sequence":"additional","affiliation":[{"name":"Clinical Neurosciences Division, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-9638-3638","authenticated-orcid":false,"given":"Elizabeth","family":"Cabrera-Ruiz","sequence":"additional","affiliation":[{"name":"Basic Neurosciences Division, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6815-8945","authenticated-orcid":false,"given":"Alexandra","family":"Luna-Angulo","sequence":"additional","affiliation":[{"name":"Neuromuscular Diseases Laboratory, Clinical Neurosciences Division, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4268-0142","authenticated-orcid":false,"given":"Gonzalo","family":"P\u00e9rez de la Cruz","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Faculty of Sciences, Universidad Nacional Aut\u00f3noma de M\u00e9xico (UNAM), Mexico City 04510, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jes\u00fas F.","family":"Valencia-Le\u00f3n","sequence":"additional","affiliation":[{"name":"Direcci\u00f3n General Adjunta de Sanidad Naval, Secretar\u00eda de Marina Armada de M\u00e9xico, Mexico City 04830, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3178-7016","authenticated-orcid":false,"given":"Paul","family":"Carillo-Mora","sequence":"additional","affiliation":[{"name":"Clinical Neurosciences Division, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0680-8516","authenticated-orcid":false,"given":"Carlos","family":"Landa-Sol\u00eds","sequence":"additional","affiliation":[{"name":"Tissue Engineering, Cell Therapy and Regenerative Medicine Unit, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4741-1793","authenticated-orcid":false,"given":"Edgar","family":"Rangel-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Cell Reprogramming Laboratory, National Institute of Neurology and Neurosurgery \u201cManuel Velasco Su\u00e1rez\u201d, Mexico City 14269, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8245-7271","authenticated-orcid":false,"given":"Abril","family":"Morraz-Varela","sequence":"additional","affiliation":[{"name":"Neuromuscular Diseases Laboratory, Clinical Neurosciences Division, National Institute of Rehabilitation \u201cLuis Guillermo Ibarra Ibarra\u201d, Mexico City 14389, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marco Tulio","family":"Romero-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Center for Research in Applied Biotechnology, National Polytechnic Institute, Santa In\u00e9s Tecuexcomac 90700, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1451-8754","authenticated-orcid":false,"given":"Ver\u00f3nica","family":"P\u00e9rez de la Cruz","sequence":"additional","affiliation":[{"name":"Neurobiochemistry and Behavior Laboratory, National Institute of Neurology and Neurosurgery \u201cManuel Velasco Su\u00e1rez\u201d, Mexico City 14269, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,9]]},"reference":[{"key":"ref_1","unstructured":"(2025, May 22). 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