{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T15:45:48Z","timestamp":1775490348770,"version":"3.50.1"},"reference-count":101,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,10]],"date-time":"2021-12-10T00:00:00Z","timestamp":1639094400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/121802\/2016"],"award-info":[{"award-number":["SFRH\/BD\/121802\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BPD\/115112\/2016"],"award-info":[{"award-number":["SFRH\/BPD\/115112\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BPD\/100948\/2014"],"award-info":[{"award-number":["SFRH\/BPD\/100948\/2014"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministerio de Ciencia e Innovaci\u00f3n","award":["PID2020-113788RB-I00"],"award-info":[{"award-number":["PID2020-113788RB-I00"]}]},{"DOI":"10.13039\/501100003176","name":"Ministerio de Educaci\u00f3n Cultura y Deporte","doi-asserted-by":"publisher","award":["BEAGAL18\/00142"],"award-info":[{"award-number":["BEAGAL18\/00142"]}],"id":[{"id":"10.13039\/501100003176","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Ageing is accompanied with a decline in several physiological systems. Frailty is an age-related syndrome correlated to the loss of homeostasis and increased vulnerability to stressors, which is associated with increase in the risk of disability, comorbidity, hospitalisation, and death in older adults. The aim of this study was to understand the relationship between frailty syndrome, immune activation, and oxidative stress. Serum concentrations of vitamins A and E were also evaluated, as well as inflammatory biomarkers (CRP and IL-6) and oxidative DNA levels. A group of Portuguese older adults (\u226565 years old) was engaged in this study and classified according to Fried\u2019s frailty phenotype. Significant increases in the inflammatory mediators (CRP and IL-6), neopterin levels, kynurenine to tryptophan ratio (Kyn\/Trp), and phenylalanine to tyrosine ratio (Phe\/Tyr), and significant decreases in Trp and Tyr concentrations were observed in the presence of frailty. IL-6, neopterin, and Kyn\/Trp showed potential as predictable biomarkers of frailty syndrome. Several clinical parameters such as nutrition, dependency scales, and polypharmacy were related to frailty and, consequently, may influence the associations observed. Results obtained show a progressive immune activation and production of pro-inflammatory molecules in the presence of frailty, agreeing with the inflammageing model. Future research should include different dimensions of frailty, including psychological, social, biological, and environmental factors.<\/jats:p>","DOI":"10.3390\/antiox10121975","type":"journal-article","created":{"date-parts":[[2021,12,10]],"date-time":"2021-12-10T08:17:58Z","timestamp":1639124278000},"page":"1975","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Exploring Early Detection of Frailty Syndrome in Older Adults: Evaluation of Oxi-Immune Markers, Clinical Parameters and Modifiable Risk Factors"],"prefix":"10.3390","volume":"10","author":[{"given":"Armanda","family":"Teixeira-Gomes","sequence":"first","affiliation":[{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas 135, 4050-600 Porto, Portugal"},{"name":"Environmental Health Department, National Institute of Health Doutor Ricardo Jorge, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"School of Medicine and Biomedical Sciences (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), Rua das Taipas 135, 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7649-2599","authenticated-orcid":false,"given":"Blanca","family":"Laffon","sequence":"additional","affiliation":[{"name":"Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Grupo DICOMOSA, Departamento de Psicolog\u00eda, Facultad de Ciencias de la Educaci\u00f3n, Campus Elvi\u00f1a s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Instituto de Investigaci\u00f3n Biom\u00e9dica de A Coru\u00f1a (INIBIC), AE CICA-INIBIC. Oza, 15071 A Coru\u00f1a, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5572-1089","authenticated-orcid":false,"given":"Vanessa","family":"Valdiglesias","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n Biom\u00e9dica de A Coru\u00f1a (INIBIC), AE CICA-INIBIC. Oza, 15071 A Coru\u00f1a, Spain"},{"name":"Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Grupo NanoToxGen, Departamento de Biolog\u00eda, Facultad de Ciencias, Campus A Zapateira s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1532-5177","authenticated-orcid":false,"given":"Johanna M.","family":"Gostner","sequence":"additional","affiliation":[{"name":"Institute of Medical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8266-5513","authenticated-orcid":false,"given":"Thomas","family":"Felder","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Paracelsus Medical University, 5020 Salzburg, Austria"}]},{"given":"Carla","family":"Costa","sequence":"additional","affiliation":[{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas 135, 4050-600 Porto, Portugal"},{"name":"Environmental Health Department, National Institute of Health Doutor Ricardo Jorge, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), Rua das Taipas 135, 4050-600 Porto, Portugal"}]},{"given":"Joana","family":"Madureira","sequence":"additional","affiliation":[{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas 135, 4050-600 Porto, Portugal"},{"name":"Environmental Health Department, National Institute of Health Doutor Ricardo Jorge, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), Rua das Taipas 135, 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1627-9563","authenticated-orcid":false,"given":"Dietmar","family":"Fuchs","sequence":"additional","affiliation":[{"name":"Institute of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8693-5250","authenticated-orcid":false,"given":"Jo\u00e3o Paulo","family":"Teixeira","sequence":"additional","affiliation":[{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas 135, 4050-600 Porto, Portugal"},{"name":"Environmental Health Department, National Institute of Health Doutor Ricardo Jorge, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), Rua das Taipas 135, 4050-600 Porto, Portugal"}]},{"given":"Solange","family":"Costa","sequence":"additional","affiliation":[{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas 135, 4050-600 Porto, Portugal"},{"name":"Environmental Health Department, National Institute of Health Doutor Ricardo Jorge, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), Rua das Taipas 135, 4050-600 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,10]]},"reference":[{"key":"ref_1","unstructured":"(2021, May 09). 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