Hyperbaric oxygen suppresses hypoxic-ischemic brain damage in newborn rats.
The optimal therapeutic time-window and protective mechanism of hyperbaric oxygen in hypoxic-ischemic brain damage remain unclear. This study aimed to determine the neuroprotective effects of hyperbaric oxygen. Following hypoxic-ischemic brain damage modeling in neonatal rats, hyperbaric oxygen was administered at 6, 24, 48, and 72 hours and 1 week after hypoxia, respectively, once daily for 1 week. Fourteen days after hypoxic-ischemic brain damage, cell density and apoptosis rate, number of Fas-L+, caspase-8+, and caspase-3+ neuronal cells, levels of nitric oxide, malondialdehyde, and superoxide dismutase in hippocampus were examined. Morris water maze test was conducted 28 days after insult. Significant improvements were found in cell density, rate of apoptosis, oxidative stress markers, FasL, and caspases in rats treated with hyperbaric oxygen within 72 hours compared to hypoxic-ischemic injury. Similarly, time-dependent behavioral amelioration was observed in pups treated with hyperbaric oxygen. Our findings suggest that hyperbaric oxygen protects against hypoxic-ischemic brain damage by inhibiting oxidative stress and FasL-induced apoptosis, and optimal therapeutic time window is within 72 hours after hypoxic-ischemic brain damage.
Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China Department of Neurology and Rehabilitation, Nanjing Children's Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China.
Min
M
Zhu
Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China.
Mengru
M
Lu
Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China.
Qing-Jie
QJ
Li
Department of Neurology, Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, P. R. China.
Zhuo
Z
Zhang
Department of Neurology, Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, P. R. China.
Zheng-Zheng
ZZ
Wu
Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China Department of Neurology, Affiliated Yixing People's Hospital of Jiangsu University, Yixing City, Jiangsu, China.
Jie
J
Li
Department of Neurology, Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, P. R. China.
Lai
L
Qian
Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China Department of Neurology, Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, P. R. China xuyun20042001@aliyun.com.
Yun
Y
Xu
Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China Department of Neurology, Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, P. R. China wangzhngy@163.com.
Zhong-Yuan
ZY
Wang
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000502:physiology*; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D002452:Cell Count; D004195:Disease Models, Animal; D006624:Hippocampus / Q000473:pathology*; D006931:Hyperbaric Oxygenation / Q000379:methods*; D020925:Hypoxia-Ischemia, Brain / Q000473:pathology / Q000628:therapy*; D020287:In Situ Nick-End Labeling; D008315:Malondialdehyde; D018782:Maze Learning; D009474:Neurons / Q000473:pathology; D009569:Nitric Oxide / Q000378:metabolism; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
D009569:Nitric Oxide; D008315:Malondialdehyde; D013482:Superoxide Dismutase; D053148:Caspase 3; D053181:Caspase 8; D010751:Phosphopyruvate Hydratase
apoptosis; hippocampus; hyperbaric oxygen; hypoxic-ischemic brain damage; therapeutic window