Zhao Fan, Xi Guohua, Liu Wenqaun, Keep Richard F, Hua Ya
Department of Neurosurgery, University of Michigan, 5018 BSRB, Ann Arbor, MI, 48109-2200, USA.
Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China.
Acta Neurochir Suppl. 2016;121:361-5. doi: 10.1007/978-3-319-18497-5_62.
Iron plays an important role in brain injury after intracerebral hemorrhage (ICH). Our previous study found minocycline reduces iron overload after ICH. The present study examined the effects of minocycline on the subacute brain injury induced by iron. Rats had an intracaudate injection of 50 μl of saline, iron, or iron + minocycline. All the animals were euthanized at day 3. Rat brains were used for immunohistochemistry (n = 5-6 per each group) and Western blotting assay (n = 4). Brain swelling, blood-brain barrier (BBB) disruption, and iron-handling proteins were measured. We found that intracerebral injection of iron resulted in brain swelling, BBB disruption, and brain iron-handling protein upregulation (p < 0.05). The co-injection of minocycline with iron significantly reduced iron-induced brain swelling (n = 5, p < 0.01). Albumin, a marker of BBB disruption, was measured by Western blot analysis. Minocycline significantly decreased albumin protein levels in the ipsilateral basal ganglia (p < 0.01). Iron-handling protein levels in the brain, including ceruloplasmin and transferrin, were reduced in the minocycline co-injected animals. In conclusion, the present study suggests that minocycline attenuates brain swelling and BBB disruption via an iron-chelation mechanism.
铁在脑出血(ICH)后的脑损伤中起重要作用。我们之前的研究发现米诺环素可减轻脑出血后的铁过载。本研究检测了米诺环素对铁诱导的亚急性脑损伤的影响。大鼠尾状核内注射50μl生理盐水、铁或铁+米诺环素。所有动物在第3天安乐死。大鼠脑用于免疫组织化学(每组n = 5 - 6)和蛋白质印迹分析(n = 4)。检测脑肿胀、血脑屏障(BBB)破坏及铁处理蛋白。我们发现脑内注射铁导致脑肿胀、BBB破坏及脑铁处理蛋白上调(p < 0.05)。米诺环素与铁共同注射显著减轻了铁诱导的脑肿胀(n = 5,p < 0.01)。通过蛋白质印迹分析检测血脑屏障破坏标志物白蛋白。米诺环素显著降低同侧基底神经节中的白蛋白蛋白水平(p < 0.01)。在共同注射米诺环素的动物中,脑中包括铜蓝蛋白和转铁蛋白在内的铁处理蛋白水平降低。总之,本研究表明米诺环素通过铁螯合机制减轻脑肿胀和血脑屏障破坏。