背景:缺血区脑血管调节的恢复和脑血流的改善对于改善卒中后的临床预后至关重要。安公牛黄丸(AGNHW)是一种著名的传统复方中药,已用于治疗急性缺血性中风超过220年;然而,其在脑血流调节中的作用尚不清楚。本研究的目的是研究AGNHW对缺血性中风后脑血流量和微循环的调节作用,并阐明其相关机制。
方法:雄性C57BL/6小鼠接受远端大脑中动脉闭塞(dMCAO),并随机分配到假手术组,MCAO,或AGNHW团体。在dMCAO后1小时胃内给予AGNHW。用旋转杆试验评价行为功能;用TTC测定梗死体积;通过检测脑SOD水平评价缺血性损伤,MDA和NO。然后,使用激光散斑对比成像评估皮质灌注和乙酰唑胺诱导的脑血管反应性,使用双光子激光扫描显微镜检测皮质毛细血管中红细胞的速度和通量。此外,我们使用RNA-Seq鉴定基因表达谱的变异,并通过测量血管活性介质水平评估微循环功能障碍的内皮依赖性变化.
结果:AGNHW显著增加脑血流量,减少梗死体积,促进脑缺血后功能恢复。AGNHW增加了毛细血管中红细胞的速度和通量,并改善了缺血性皮质中的脑血管反应性。此外,AGNHW调节内皮依赖性微循环,内皮素(Edn1,Edn3和Ednrb)的表达降低以及脑和血清TXB2/6-酮-PGF1α和ET-1/CGRP的比率降低。
结论:AGNHW改善脑低灌注,调节脑血管反应性和减轻中风后缺血皮质内的微循环功能障碍。通过调节与血管内皮细胞功能相关的基因的表达和调节内皮依赖性血管活性介质来实现这一突出效果。
BACKGROUND: The restoration of cerebrovascular regulation and improvement of cerebral blood flow in ischaemic regions are crucial for improving the clinical prognosis after stroke. An-Gong-Niu-Huang-Wan (AGNHW) is a famous traditional compound Chinese medicine that has been used for over 220 years to treat acute ischaemic stroke; however, its role in the regulation of cerebral blood flow is still unclear. The aim of the present study was to investigate the regulatory effect of AGNHW on cerebral blood flow and microcirculation after ischaemic stroke and to elucidate the underlying mechanisms involved.
METHODS: Male C57BL/6 mice were subjected to distal middle cerebral artery occlusion (dMCAO) and randomly assigned to the sham, MCAO, or AGNHW groups. AGNHW was administered intragastrically 1 h after dMCAO. The rotarod test was utilized to evaluate behavioural function; TTC was used to determine the infarct volume; and ischaemic injury was assessed by detecting brain levels of SOD, MDA and NO. Then, cortical perfusion and acetazolamide-induced cerebrovascular reactivity were assessed using laser speckle contrast imaging, and the velocity and flux of red blood cells in cortical capillaries were detected using two-photon laser scanning microscopy. In addition, we employed RNA-Seq to identify variations in gene expression profiles and assessed endothelium-dependent changes in microcirculatory dysfunction by measuring vasoactive mediator levels.
RESULTS: AGNHW significantly increased cerebral blood flow, reduced the infarct volume, and promoted functional recovery after cerebral ischaemia. AGNHW increased the velocity and flux of red blood cells in capillaries and improved cerebrovascular reactivity in the ischaemic cortex. Furthermore, AGNHW regulated endothelium-dependent microcirculation, as evidenced by decreases in the expression of endothelins (Edn1, Edn3 and Ednrb) and the ratios of brain and serum TXB2/6-keto-PGF1α and ET-1/CGRP.
CONCLUSIONS: AGNHW improved cerebral hypoperfusion, regulated cerebrovascular reactivity and attenuated microcirculatory dysfunction within the ischaemic cortex after stroke. This outstanding effect was achieved by modulating the expression of genes related to vascular endothelial cell function and regulating endothelium-dependent vasoactive mediators.