{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T16:08:29Z","timestamp":1791648509592,"version":"4.3.4"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T00:00:00Z","timestamp":1758153600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000646","name":"JSPS KAKENHI Grant-in-Aid for Scientific Research (C)","doi-asserted-by":"publisher","award":["22K10009"],"award-info":[{"award-number":["22K10009"]}],"id":[{"id":"10.13039\/501100000646","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000646","name":"JSPS KAKENHI Grant-in-Aid for Scientific Research (C)","doi-asserted-by":"publisher","award":["24K19929"],"award-info":[{"award-number":["24K19929"]}],"id":[{"id":"10.13039\/501100000646","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000646","name":"Grant in Aid for Early-Career Scientists","doi-asserted-by":"publisher","award":["22K10009"],"award-info":[{"award-number":["22K10009"]}],"id":[{"id":"10.13039\/501100000646","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000646","name":"Grant in Aid for Early-Career Scientists","doi-asserted-by":"publisher","award":["24K19929"],"award-info":[{"award-number":["24K19929"]}],"id":[{"id":"10.13039\/501100000646","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Hypoxia-induced oxidative stress and inflammation in the brain are critical contributors to neurological disorders. Hydrogen gas has emerged as a therapeutic agent with potent antioxidant and anti-inflammatory properties. In this study, we evaluated the protective effects of hydrogen against acute hypoxia-induced brain injuries in medaka. Fish were exposed to hypoxia and then recovered in water bubbled with air, hydrogen, or ozone. LOX-1 hypoxia probe imaging and HIF-1\u03b1 immunostaining showed persistent tissue hypoxia in the air and ozone groups, which was significantly reduced by hydrogen treatment. Histological analysis revealed extensive vascular congestion in the midbrain after hypoxia, which was markedly alleviated by hydrogen. TUNEL assay demonstrated that hydrogen suppressed hypoxia-induced neuronal apoptosis. Immunohistochemistry and ELISA showed elevated levels of 8-hydroxy-2\u2032-deoxyguanosine (8-OHdG) and proinflammatory markers (COX-2, IL-6, TNF-\u03b1) in the brains of air- and ozone-treated fish; these increases were significantly attenuated by hydrogen. ORAC assay confirmed that hydrogen restored brain antioxidant capacity. Behavioral analysis further demonstrated that hydrogen treatment improved locomotor activity and stabilized respiratory function. These results indicate that hydrogen protects medaka against hypoxia-induced oxidative and inflammatory injuries and may represent a promising therapeutic strategy for hypoxia-related neurological disorders.<\/jats:p>","DOI":"10.3390\/antiox14091130","type":"journal-article","created":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T12:24:25Z","timestamp":1758198265000},"page":"1130","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Hydrogen Gas Mitigates Acute Hypoxia-Induced Oxidative and Inflammatory Brain Injuries in Medaka (Oryzias latipes)"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-6269-5049","authenticated-orcid":false,"given":"Eriko","family":"Sato","sequence":"first","affiliation":[{"name":"Department of Physiology, School of Life Dentistry at Tokyo, The Nippon Dental University, 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan"},{"name":"Department of Dental Anesthesiology, School of Life Dentistry at Tokyo, The Nippon Dental University, Tokyo 102-8159, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2636-2152","authenticated-orcid":false,"given":"Naohiro","family":"Shimamura","sequence":"additional","affiliation":[{"name":"Department of Dental Anesthesiology, School of Life Dentistry at Tokyo, The Nippon Dental University, Tokyo 102-8159, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chikako","family":"Saiki","sequence":"additional","affiliation":[{"name":"Department of Physiology, School of Life Dentistry at Tokyo, The Nippon Dental University, 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katsuhisa","family":"Sunada","sequence":"additional","affiliation":[{"name":"Department of Dental Anesthesiology, School of Life Dentistry at Tokyo, The Nippon Dental University, Tokyo 102-8159, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8224-912X","authenticated-orcid":false,"given":"Nobuhiko","family":"Miwa","sequence":"additional","affiliation":[{"name":"Incorporated Association Hydrogen Medical Institute, Minatojima Minamicho 1-6-4, ChuOh-Ku, Kobe 650-0047, Japan"},{"name":"Faculty of Life Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3053-4930","authenticated-orcid":false,"given":"Li","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Physiology, School of Life Dentistry at Tokyo, The Nippon Dental University, 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,18]]},"reference":[{"key":"ref_1","unstructured":"Lacerte, M., Hays Shapshak, A., and Mesfin, F.B. (2025, June 11). Hypoxic Brain Injury, StatPearls [Internet], Available online: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK537310\/."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"151228","DOI":"10.1016\/j.scitotenv.2021.151228","article-title":"Hypoxia causes mitochondrial dysfunction and brain memory disorder in a manner mediated by the reduction of Cirbp","volume":"806","author":"Liu","year":"2022","journal-title":"Sci. Total Environ."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Chen, R., Lai, U.H., Zhu, L., Singh, A., Ahmed, M., and Forsyth, N.R. (2018). Reactive oxygen species formation in the brain at different oxygen levels: The role of hypoxia inducible factors. Front. Cell Dev. Biol., 6.","DOI":"10.3389\/fcell.2018.00132"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Mukandala, G., Tynan, R., Lanigan, S., and O\u2019Connor, J.J. (2016). The effects of hypoxia and inflammation on synaptic signaling in the CNS. Brain Sci., 6.","DOI":"10.3390\/brainsci6010006"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1401","DOI":"10.1016\/j.jnutbio.2015.08.001","article-title":"The complexity of the Nrf2 pathway: Beyond the antioxidant response","volume":"26","author":"Huang","year":"2015","journal-title":"J. Nutr. Biochem."},{"key":"ref_6","unstructured":"Gillam-Krakauer, M., Shah, M., and Gowen, C.W. (2025, June 11). Birth Asphyxia, StatPearls [Internet], Available online: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK430782\/."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"101343","DOI":"10.1016\/j.arr.2021.101343","article-title":"Hypoxia and brain aging: Neurodegeneration or neuroprotection?","volume":"68","author":"Burtscher","year":"2021","journal-title":"Ageing Res. Rev."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e13258","DOI":"10.14814\/phy2.13258","article-title":"Chronic intermittent hypoxia induces oxidative stress and inflammation in brain regions associated with early-stage neurodegeneration","volume":"5","author":"Snyder","year":"2017","journal-title":"Physiol. Rep."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2824","DOI":"10.1210\/en.2015-1738","article-title":"Effects of oxidative stress and testosterone on pro-inflammatory signaling in a female rat dopaminergic neuronal cell line","volume":"157","author":"Holmes","year":"2016","journal-title":"Endocrinology"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1016\/j.brainresrev.2009.09.006","article-title":"The role and regulation of hypoxia-inducible factor-1\u03b1 expression in brain development and neonatal hypoxic-ischemic brain injury","volume":"62","author":"Fan","year":"2009","journal-title":"Brain Res. Rev."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1125","DOI":"10.1038\/s41419-018-1180-y","article-title":"Brain injury induces HIF-1\u03b1-dependent transcriptional activation of LRRK2 that exacerbates brain damage","volume":"9","author":"Bae","year":"2018","journal-title":"Cell Death Dis."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Choi, Y.K. (2024). Detrimental roles of hypoxia-inducible factor-1\u03b1 in severe hypoxic brain diseases. Int. J. Mol. Sci., 25.","DOI":"10.3390\/ijms25084465"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"601","DOI":"10.1074\/jbc.272.1.601","article-title":"Hypoxia induces cyclooxygenase-2 via the NF-\u03baB p65 transcription factor in human vascular endothelial cells","volume":"272","author":"Schmedtje","year":"1997","journal-title":"J. Biol. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Ha, J.S., Choi, H.R., Kim, I.S., Kim, E.A., Cho, S.W., and Yang, S.J. (2021). Hypoxia-induced S100A8 expression activates microglial inflammation and promotes neuronal apoptosis. Int. J. Mol. Sci., 22.","DOI":"10.3390\/ijms22031205"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3453059","DOI":"10.1155\/2016\/3453059","article-title":"Cox-2 inhibition protects against hypoxia\/reoxygenation-induced cardiomyocyte apoptosis via Akt-dependent enhancement of iNOS expression","volume":"2016","author":"Pang","year":"2016","journal-title":"Oxid. Med. Cell. Longev."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1180","DOI":"10.2174\/1570159X18666200429004242","article-title":"MicroRNAs in the blood-brain barrier in hypoxic-ischemic brain injury","volume":"18","author":"Shen","year":"2020","journal-title":"Curr. Neuropharmacol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1749","DOI":"10.1007\/s12035-022-03175-w","article-title":"Molecular hydrogen: An emerging therapeutic medical gas for brain disorders","volume":"60","author":"Wu","year":"2023","journal-title":"Mol. Neurobiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1016\/j.brainres.2014.09.030","article-title":"Inhalation of hydrogen gas attenuates brain injury in mice with cecal ligation and puncture via inhibiting neuroinflammation, oxidative stress and neuronal apoptosis","volume":"1589","author":"Liu","year":"2014","journal-title":"Brain Res."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Liu, L., Wang, S., Jiang, L., Wang, J., Chen, J., Zhang, H., and Wang, Y. (2025). Molecular hydrogen mitigates traumatic brain injury-induced lung injury via NLRP3 inflammasome inhibition. BMC Chem., 19.","DOI":"10.1186\/s13065-025-01513-2"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"101907","DOI":"10.1016\/j.eclinm.2023.101907","article-title":"Efficacy of inhaled hydrogen on neurological outcome following brain ischaemia during post-cardiac arrest care (HYBRID II): A multi-centre, randomised, double-blind, placebo-controlled trial","volume":"58","author":"Tamura","year":"2023","journal-title":"EClinicalMedicine"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1260","DOI":"10.1007\/s10646-014-1269-8","article-title":"Hypoxia turns genotypic female medaka fish into phenotypic males","volume":"23","author":"Cheung","year":"2014","journal-title":"Ecotoxicology"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"12114","DOI":"10.1038\/ncomms12114","article-title":"Hypoxia causes transgenerational impairments in reproduction of fish","volume":"7","author":"Wang","year":"2016","journal-title":"Nat. Commun."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Lai, K.P., Tam, N., Wang, S.Y., Tse, W.K.F., Lin, X., Chan, T.F., Tong, Y., Zhang, J.W., Au, D.W.T., and Wu, R.S.S. (2021). Proteomic response of the brain to hypoxic stress in marine medaka fish (Oryzias melastigma). Front. Mar. Sci., 8.","DOI":"10.3389\/fmars.2021.618489"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Xiao, L., Sato, E., Ide, R., Shimamura, N., Saiki, C., and Miwa, N. (2025). Comparative Analysis of Davidson and Glyoxal Fixatives on Autofluorescence and Immunolabeling in Medaka (Oryzias latipes) Tissues. Biomedicines, 13.","DOI":"10.3390\/biomedicines13082002"},{"key":"ref_25","first-page":"2126","article-title":"Intraperitoneal injection into adult zebrafish","volume":"42","author":"Kinkel","year":"2010","journal-title":"J. Vis. Exp."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"12564","DOI":"10.1073\/pnas.0914191107","article-title":"Loss of human Greatwall results in G2 arrest and multiple mitotic defects due to deregulation of the cyclin B-Cdc2\/PP2A balance","volume":"107","author":"Burgess","year":"2010","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2270","DOI":"10.4103\/1673-5374.285000","article-title":"Enzyme-digested Colla Corii Asini (E\u2019jiao) prevents hydrogen peroxide-induced cell death and accelerates amyloid beta clearance in neuronal-like PC12 cells","volume":"15","author":"Xiao","year":"2020","journal-title":"Neural Regen. Res."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1007\/s13577-016-0150-x","article-title":"Hydrogen-rich water achieves cytoprotection from oxidative stress injury in human gingival fibroblasts in culture or 3D-tissue equivalents, and wound-healing promotion, together with ROS-scavenging and relief from glutathione diminishment","volume":"30","author":"Xiao","year":"2017","journal-title":"Hum. Cell"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1637","DOI":"10.21873\/invivo.11955","article-title":"A new method for testing filtration efficiency of mask materials under sneeze-like pressure","volume":"34","author":"Xiao","year":"2020","journal-title":"In Vivo"},{"key":"ref_30","first-page":"88","article-title":"Zebrafish as an alternative model for hypoxic-ischemic brain damage","volume":"3","author":"Yu","year":"2011","journal-title":"Int. J. Physiol. Pathophysiol. Pharmacol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"926","DOI":"10.1126\/science.1156401","article-title":"Spreading dead zones and consequences for marine ecosystems","volume":"321","author":"Diaz","year":"2008","journal-title":"Science"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1429","DOI":"10.1089\/neu.2014.3445","article-title":"Alterations in cholinergic pathways and therapeutic strategies targeting cholinergic system after traumatic brain injury","volume":"32","author":"Shin","year":"2015","journal-title":"J. Neurotrauma"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"3915","DOI":"10.1007\/s10571-023-01413-w","article-title":"The impact of cerebral ischemia on antioxidant enzymes activity and neuronal damage in the hippocampus","volume":"43","author":"Sadeghzadeh","year":"2023","journal-title":"Cell. Mol. Neurobiol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"113457","DOI":"10.1016\/j.expneurol.2020.113457","article-title":"Animal models for neonatal brain injury induced by hypoxic ischemic conditions in rodents","volume":"334","author":"Hamdy","year":"2020","journal-title":"Exp. Neurol."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Guan, P., Sun, Z.M., Luo, L.F., Zhao, Y.S., Yang, S.C., Yu, F.Y., Wang, N., and Ji, E.S. (2019). Hydrogen gas alleviates chronic intermittent hypoxia-induced renal injury through reducing iron overload. Molecules, 24.","DOI":"10.3390\/molecules24061184"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1016\/bs.mie.2014.11.038","article-title":"Molecular hydrogen as a novel antioxidant: Overview of the advantages of hydrogen for medical applications","volume":"555","author":"Ohta","year":"2015","journal-title":"Methods Enzymol."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Sim, M., Kim, C.S., Shon, W.J., Lee, Y.K., Choi, E.Y., and Shin, D.M. (2020). Hydrogen-rich water reduces inflammatory responses and prevents apoptosis of peripheral blood cells in healthy adults: A randomized, double-blind, controlled trial. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-68930-2"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Xiao, L., and Miwa, N. (2021). Hydrogen nano-bubble water suppresses ROS generation, adipogenesis, and interleukin-6 secretion in hydrogen-peroxide- or PMA-stimulated adipocytes and three-dimensional subcutaneous adipose equivalents. Cells, 10.","DOI":"10.3390\/cells10030626"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"350","DOI":"10.1016\/j.bbrc.2011.05.024","article-title":"Hydrogen-rich medium protects human skin fibroblasts from high glucose or mannitol induced oxidative damage","volume":"409","author":"Yu","year":"2011","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Cheng, D., Long, J., Zhao, L., and Liu, J. (2023). Hydrogen: A Rising Star in Gas Medicine as a Mitochondria-Targeting Nutrient via Activating Keap1-Nrf2 Antioxidant System. Antioxidants, 12.","DOI":"10.20944\/preprints202310.1953.v1"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/j.bbrc.2011.04.008","article-title":"Hydrogen inhalation reduced epithelial apoptosis in ventilator-induced lung injury via a mechanism involving nuclear factor-kappa B activation","volume":"408","author":"Huang","year":"2011","journal-title":"Biochem. Biophys. Res. Commun."}],"container-title":["Antioxidants"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-3921\/14\/9\/1130\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:47:51Z","timestamp":1760035671000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-3921\/14\/9\/1130"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,18]]},"references-count":41,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["antiox14091130"],"URL":"https:\/\/doi.org\/10.3390\/antiox14091130","relation":{},"ISSN":["2076-3921"],"issn-type":[{"value":"2076-3921","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,18]]}}}