{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T05:04:16Z","timestamp":1775192656970,"version":"3.50.1"},"reference-count":138,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,10,25]],"date-time":"2025-10-25T00:00:00Z","timestamp":1761350400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o Grunenthal"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Fibromyalgia is a prevalent chronic pain disorder characterized by widespread musculoskeletal pain, fatigue, cognitive dysfunction, and sleep disturbances, with high impact in quality of life. Despite extensive research, the pathophysiological mechanisms of fibromyalgia remain partially understood, complicating the diagnosis and treatment. Some evidence underscores the central role of abnormal pain processing, particularly central sensitization and defective descending pain modulation pathways. This review synthesizes and discusses current findings on the neurobiological underpinnings of pain in fibromyalgia, with focus on descending inhibitory control mechanisms and on the role of biomarkers. We integrate data from neurochemical, neuroimaging, and clinical studies to explain how impaired descending modulation contributes to enhanced pain sensitivity and discuss the putative biomarkers associated with changes in descending modulation. A better understanding of descending pain modulation dysfunction in fibromyalgia and related biomarkers is crucial for improving clinical outcomes and developing novel and more effective treatments.<\/jats:p>","DOI":"10.3390\/diagnostics15212702","type":"journal-article","created":{"date-parts":[[2025,10,27]],"date-time":"2025-10-27T07:31:58Z","timestamp":1761550318000},"page":"2702","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Descending Pain Modulation in Fibromyalgia: A Short Review of Mechanisms and Biomarkers"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3434-2247","authenticated-orcid":false,"given":"Bruno Daniel","family":"Carneiro","sequence":"first","affiliation":[{"name":"Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal"},{"name":"Rheumatology Service, Unidade Local de Sa\u00fade do Alto Minho, Hospital Conde de Bertiandos, 4990-078 Ponte de Lima, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2009-1945","authenticated-orcid":false,"given":"Sandra","family":"Torres","sequence":"additional","affiliation":[{"name":"Unidade de Sa\u00fade Familiar S\u00e3o Jo\u00e3o, Unidade Local de Sa\u00fade de Entre Douro e Vouga, 3700-298 S\u00e3o Jo\u00e3o da Madeira, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5623-8531","authenticated-orcid":false,"given":"Jos\u00e9 Tiago","family":"Costa-Pereira","sequence":"additional","affiliation":[{"name":"Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal"},{"name":"Faculty of Nutrition and Food Sciences, University of Porto, 4150-180 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health and IBMC (i3S), University of Porto, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2119-4479","authenticated-orcid":false,"given":"Daniel Humberto","family":"Pozza","sequence":"additional","affiliation":[{"name":"Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health and IBMC (i3S), University of Porto, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5696-1239","authenticated-orcid":false,"given":"Isaura","family":"Tavares","sequence":"additional","affiliation":[{"name":"Unit of Experimental Biology, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health and IBMC (i3S), University of Porto, 4200-135 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1547","DOI":"10.1001\/jama.2014.3266","article-title":"Fibromyalgia: A Clinical Review","volume":"311","author":"Clauw","year":"2014","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"356","DOI":"10.1007\/s11916-013-0356-5","article-title":"Worldwide epidemiology of fibromyalgia","volume":"17","author":"Queiroz","year":"2013","journal-title":"Curr. 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