{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T23:27:50Z","timestamp":1787614070156,"version":"build-2736575974"},"reference-count":50,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T00:00:00Z","timestamp":1774569600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>N-acetylcysteine (NAC) is a glutathione precursor with established antioxidant and anti-inflammatory properties that has been investigated as a neuroprotective agent across multiple neurological conditions. This systematic review systematically mapped the clinical evidence for NAC across seven neurological disorders. PubMed and Cochrane Library were searched for studies published between 1 January 1995 and 31 December 2025. Twenty-three studies were included: traumatic brain injury (TBI, n = 6), Alzheimer\u2019s disease (AD, n = 5), Parkinson\u2019s disease (PD, n = 5), multiple sclerosis (n = 4), amyotrophic lateral sclerosis (n = 2), and migraine (n = 1); no eligible epilepsy studies were identified. The strongest evidence emerged for acute mild TBI, where early NAC administration significantly improved symptom resolution, and for PD, where combined intravenous\/oral NAC improved dopamine transporter binding. In AD, nutraceutical formulations including NAC and other active compounds showed trends toward cognitive stabilization. Most included studies had a high or serious risk of bias, and only eight of 23 assessed oxidative stress biomarkers. NAC demonstrated a favorable safety profile across all conditions. Despite fragmented and heterogeneous evidence, the encouraging signals identified warrant large-scale randomized controlled trials with a standardized biomarker assessment.<\/jats:p>","DOI":"10.3390\/ijms27073076","type":"journal-article","created":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T15:45:42Z","timestamp":1774626342000},"page":"3076","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["N-Acetylcysteine in Neurological Disorders: A Systematic Review of Clinical and Translational Evidence Across Seven Disorders"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-3140-2274","authenticated-orcid":false,"given":"Robert","family":"M\u00eendreanu","sequence":"first","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4991-0032","authenticated-orcid":false,"given":"Irina Camelia","family":"Chi\u0219","sequence":"additional","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra","family":"Sevastre-Berghian","sequence":"additional","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cezar","family":"Login","sequence":"additional","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adina","family":"Stan","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teodora","family":"Stan","sequence":"additional","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0046-0803","authenticated-orcid":false,"given":"Simona","family":"Clichici","sequence":"additional","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2208-5132","authenticated-orcid":false,"given":"\u0218oimi\u021ba","family":"Suciu","sequence":"additional","affiliation":[{"name":"Department of Physiology, Iuliu Ha\u021bieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1016\/S1474-4422(18)30499-X","article-title":"Global, Regional, and National Burden of Neurological Disorders, 1990\u20132016: A Systematic Analysis for the Global Burden of Disease Study 2016","volume":"18","author":"Feigin","year":"2019","journal-title":"Lancet Neurol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1634","DOI":"10.1111\/j.1471-4159.2006.03907.x","article-title":"Oxidative Stress and Neurodegeneration: Where Are We Now?","volume":"97","author":"Halliwell","year":"2006","journal-title":"J. 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