Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland).
Department of Pathology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland).
Med Sci Monit. 2019 Jan 28;25:794-800. doi: 10.12659/MSM.908500.
BACKGROUND It is well documented that the Blood-Brain barrier (BBB) can be damaged by matrix metalloproteases (MMPs) after intracerebral hemorrhage (ICH), but little is known about the mechanism of this effect. MATERIAL AND METHODS We established an ICH model in rats by injecting collagenase VII into the striatum. Afterwards, intraperitoneal injection of these rats with 40 mg/kg GM6001 (a MMPs inhibitor). The effects of GM6001 on ICH were investigated by neurological severity score, brain water content, Evans blue staining, hematoxylin-eosin staining, immunohistochemical staining, and Western blot assays. RESULTS We demonstrated that the neurological damage caused by ICH was relieved at 5 and 7 days following administration of GM6001. The impaired BBB induced by ICH was improved in response to GM6001 treatment at around 3 days, as evidenced by alleviated cerebral edema, decreased Evans blue extravasation, and a reduction in inflammatory cellular infiltration. Mechanism analysis revealed that ICH induced the generation of β-dystroglycan cleavage, which could be suppressed by GM6001 treatment. Furthermore, we found that recombinant MMP2 and MMP9 triggered the cleavage of β-dystroglycan in vitro, and this action could be inhibited by GM6001 administration. CONCLUSIONS Taken together, our results suggest that MMPs-mediated cleavage on β-dystroglycan may play an important role in BBB after ICH.
大量文献证明,脑出血(ICH)后基质金属蛋白酶(MMPs)可损伤血脑屏障(BBB),但目前对于该作用机制知之甚少。
通过向纹状体注射胶原酶 VII,我们在大鼠中建立了 ICH 模型。随后,对这些大鼠进行腹腔内注射 40mg/kg GM6001(一种 MMPs 抑制剂)。通过神经功能严重程度评分、脑水含量、伊文思蓝染色、苏木精-伊红染色、免疫组织化学染色和 Western blot 分析,研究 GM6001 对 ICH 的影响。
GM6001 给药后 5 天和 7 天,ICH 引起的神经损伤得到缓解。GM6001 治疗可改善 ICH 引起的 BBB 受损,在大约 3 天内减轻脑水肿、减少伊文思蓝外渗和减少炎症细胞浸润。机制分析表明,ICH 诱导 β-肌联蛋白裂解,GM6001 治疗可抑制该作用。此外,我们发现重组 MMP2 和 MMP9 在体外引发β-肌联蛋白的裂解,GM6001 给药可抑制该作用。
综上所述,我们的结果表明 MMPs 介导的β-肌联蛋白裂解可能在 ICH 后 BBB 中发挥重要作用。