Huang Jun-Long, Liu Wen-Wu, Manaenko Anatol, Sun Xue-Jun, Mei Qi-Yong, Hu Qin
Discipline of Neuroscience, Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine; Department of Navy Aviation Medicine, Faculty of Naval Medicine, the Naval Military Medical University; Department of Navy Aviation Medicine, Naval Medical center of PLA, the Naval Military Medical University, Shanghai, China.
Department of Diving Medicine, Faculty of Naval Medicine, the Naval Military Medical University, Shanghai, China.
Med Gas Res. 2019 Jul-Sep;9(3):127-132. doi: 10.4103/2045-9912.266987.
Microglia participate in bi-directional control of brain repair after stroke. Previous studies have demonstrated that hydrogen protects brain after ischemia/reperfusion (I/R) by inhibiting inflammation, but the specific mechanism of anti-inflammatory effect of hydrogen is poorly understood. The goal of our study is to investigate whether inhalation of high concentration hydrogen (HCH) is able to attenuate I/R-induced microglia activation. Eighty C57B/L male mice were divided into four groups: sham, I/R, I/R + HCH and I/R + N/O groups. Assessment of animals happened in "blind" matter. I/R was induced by occlusion of middle cerebral artery for one hour). After one hour, filament was withdrawn, which induced reperfusion. Hydrogen treated I/R animals inhaled mix of 66.7% H balanced with O for 90 minutes, starting immediately after initiation of reperfusion. Control animals (N/O) inhaled mix in which hydrogen was replaced with N for the same time (90 minutes). The brain injury, such as brain infarction and development of brain edema, as well as neurobehavioral deficits were determined 23 hours after reperfusion. Effect of HCH on microglia activation in the ischemic penumbra was investigated by immunostaining also 23 hours after reperfusion. mRNA expression of inflammation related genes was detected by PCR. Our results showed that HCH attenuated brain injury and consequently reduced neurological dysfunction after I/R. Furthermore, we demonstrated that HCH directed microglia polarization towards anti-inflammatory M2 polarization. This study indicates hydrogen may exert neuroprotective effects by inhibiting the microglial activation and regulating microglial polarization. This study was conducted in agreement with the Animal Care and Use Committee (IACUC) and Institutional Animal Care guidelines regulation (Shanghai Jiao Tong University, China (approval No. A2015-011) in November 2015.
小胶质细胞参与中风后脑修复的双向调控。以往研究表明，氢气通过抑制炎症反应对缺血/再灌注（I/R）后的脑起到保护作用，但氢气抗炎作用的具体机制尚不清楚。本研究旨在探讨吸入高浓度氢气（HCH）是否能够减轻I/R诱导的小胶质细胞活化。80只C57B/L雄性小鼠被分为四组：假手术组、I/R组、I/R + HCH组和I/R + N/O组。对动物的评估采用“盲法”进行。通过阻断大脑中动脉1小时诱导I/R（1小时后抽出栓线诱导再灌注）。氢气处理的I/R动物在再灌注开始后立即吸入含66.7%氢气与氧气平衡的混合气体90分钟。对照动物（N/O）吸入氢气被氮气替代的相同混合气体90分钟。再灌注23小时后测定脑损伤情况，如脑梗死和脑水肿的发展，以及神经行为缺陷。再灌注23小时后还通过免疫染色研究HCH对缺血半暗带小胶质细胞活化的影响。通过PCR检测炎症相关基因的mRNA表达。我们的结果表明，HCH减轻了I/R后的脑损伤，进而降低了神经功能障碍。此外，我们证明HCH使小胶质细胞向抗炎性M2极化方向转变。本研究表明氢气可能通过抑制小胶质细胞活化和调节小胶质细胞极化发挥神经保护作用。本研究遵循动物护理与使用委员会（IACUC）及机构动物护理指南规定（中国上海交通大学，批准号A2015 - 011）于2015年11月进行。
