{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T05:47:26Z","timestamp":1785822446730,"version":"3.56.0"},"reference-count":117,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013317","name":"Key Research and Development Program of Shanxi Province","doi-asserted-by":"publisher","award":["2025ZD056"],"award-info":[{"award-number":["2025ZD056"]}],"id":[{"id":"10.13039\/501100013317","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Fundamental Research Program of Shanxi Province","award":["202403021211175"],"award-info":[{"award-number":["202403021211175"]}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>Cognitive impairment is a major sequela following aneurysmal subarachnoid hemorrhage (aSAH), severely influencing patients\u2019 long-term quality of life. Its mechanism of occurrence is complex and has not been fully clarified to date. In recent years, the role of the gut microbiota in neurological diseases has gradually been revealed, providing a compelling theoretical framework for exploring the gut-brain axis in aSAH-induced cognitive impairment. Recognizing the limitations of current cross-sectional evidence, this review explicitly aims to propose testable hypotheses rather than establish definitive causation. In this study, we propose the novel \u201cgut-derived secondary hit\u201d hypothesis, aiming to explore how secondary gut microbiota dysbiosis, triggered by primary central nervous system injury following aSAH, may act as a potential modulator contributing to long-term cognitive impairment through altered shifts in the metabolite profile. In this review, we outline the clinical manifestations and pathological mechanisms of aSAH-induced cognitive impairment, as well as the observed shifts in gut microbial composition. We further deeply explore the complex pathways through which the gut microbiome and its derived metabolites may be associated with cognitive impairment. In addition, incorporating recent advances, we discuss prospective microbiome-targeted therapeutic strategies, providing a translational perspective for future mechanistic studies and the clinical prevention and treatment of aSAH-induced cognitive impairment.<\/jats:p>","DOI":"10.3389\/fmicb.2026.1841330","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T05:38:35Z","timestamp":1785821915000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Gut microbiota and metabolites as potential modulators of cognitive impairment after aneurysmal subarachnoid hemorrhage: a hypothesis-driven review"],"prefix":"10.3389","volume":"17","author":[{"given":"Wentian","family":"Zhang","sequence":"first","affiliation":[{"name":"The First Clinical School of Medicine, Shanxi Medical University","place":["Taiyuan, China"]},{"name":"Department of Neurosurgery, Cardiovascular Hospital Affiliated to Shanxi Medical University","place":["Taiyuan, China"]},{"name":"Shanxi Key Laboratory of Heart Failure Precision Medicine","place":["Taiyuan, China"]},{"name":"Department of Neurosurgery, The First Hospital of Shanxi Medical University","place":["Taiyuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miaomiao","family":"Chen","sequence":"additional","affiliation":[{"name":"Academy of Medical Sciences, Shanxi Medical University","place":["Taiyuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tingyu","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Public Health, Shanxi Medical University","place":["Taiyuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongqin","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, The First Hospital of Shanxi Medical University","place":["Taiyuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ning","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Cardiovascular Hospital Affiliated to Shanxi Medical University","place":["Taiyuan, China"]},{"name":"Shanxi Key Laboratory of Heart Failure Precision Medicine","place":["Taiyuan, China"]},{"name":"Department of Neurosurgery, The First Hospital of Shanxi Medical University","place":["Taiyuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,4]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"lnad017","DOI":"10.1093\/lifemedi\/lnad017","article-title":"A framework of biomarkers for brain aging: a consensus statement by the aging biomarker consortium","volume":"2","author":"Jia","year":"2023","journal-title":"Life Med."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"370","DOI":"10.1038\/jcbfm.2009.223","article-title":"Cyclooxygenase-1 and -2 differentially modulate lipopolysaccharide-induced blood-brain barrier disruption through matrix metalloproteinase activity","volume":"30","author":"Aid","year":"2010","journal-title":"J. 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