Table_1_Hemorrhagic Stroke Induces a Time-Dependent Upregulation of miR-150-5p and miR-181b-5p in the Bloodstream.XLSX

To date, the only effective pharmacological treatment for ischemic stroke is limited to the clinical use of recombinant tissue plasminogen activator (rtPA), although endovascular therapy has also emerged as an effective treatment for acute ischemic stroke. Unfortunately, the benefit of this treatment is limited to a 4.5-h time window. Most importantly, the use of rtPA is contraindicated in the case of hemorrhagic stroke. Therefore, the identification of a reliable biomarker to distinguish hemorrhagic from ischemic stroke could provide several advantages, including an earlier diagnosis, a better treatment, and a faster decision on ruling out hemorrhage so that tPA may be administered earlier. microRNAs (miRNAs) are stable non-coding RNAs crucially involved in the downregulation of gene expression via mRNA cleavage or translational repression. In the present paper, taking advantage of three preclinical animal models of stroke, we compared the miRNA blood levels of animals subjected to permanent or transient middle cerebral artery occlusion (MCAO) or to collagenase-induced hemorrhagic stroke. Preliminarily, we examined the rat miRNome in the brain tissue of ischemic and sham-operated rats; then, we selected those miRNAs whose expression was significantly modulated after stroke to create a list of miRNAs potentially involved in stroke damage. These selected miRNAs were then evaluated at different time intervals in the blood of rats subjected to permanent or transient focal ischemia or to hemorrhagic stroke. We found that four miRNAs—miR-16-5p, miR-101a-3p, miR-218-5p, and miR-27b-3p—were significantly upregulated in the plasma of rats 3 h after permanent MCAO, whereas four other different miRNAs—miR-150-5p, let-7b-5p, let-7c-5p, and miR-181b-5p—were selectively upregulated by collagenase-induced hemorrhagic stroke. Collectively, our study identified some selective miRNAs expressed in the plasma of hemorrhagic rats and pointed out the importance of a precise time point measurement to render more reliable the use of miRNAs as stroke biomarkers.

迄今为止，缺血性脑卒中唯一有效的药物治疗手段仅限重组组织型纤溶酶原激活剂（recombinant tissue plasminogen activator, rtPA）的临床应用，尽管血管内治疗也已成为急性缺血性脑卒中的有效治疗方案。遗憾的是，该治疗的获益仅局限于4.5小时的时间窗内。尤为关键的是，rtPA的使用在出血性脑卒中患者中属于禁忌证。因此，识别可区分出血性与缺血性脑卒中的可靠生物标志物，将具备多重优势，包括更早的诊断、更优化的治疗方案，以及更快做出排除出血的决策，从而能够更早给予tPA治疗。微RNA（microRNAs, miRNAs）是一类稳定的非编码RNA，通过mRNA裂解或翻译抑制在基因表达下调过程中发挥关键调控作用。在本研究中，我们借助三种脑卒中临床前动物模型，对比了接受永久性或暂时性大脑中动脉闭塞（middle cerebral artery occlusion, MCAO）或胶原酶诱导出血性脑卒中的动物的血液miRNA水平。我们首先初步检测了缺血性脑卒中大鼠与假手术大鼠脑组织中的大鼠miRNA组；随后筛选出脑卒中后表达显著失调的miRNA，构建出潜在参与脑卒中损伤的miRNA列表。将这些筛选得到的miRNA在不同时间节点下，于接受永久性或暂时性局灶性脑缺血，或出血性脑卒中的大鼠血液中进行检测。我们发现，在永久性大脑中动脉闭塞术后3小时的大鼠血浆中，有4种miRNA——miR-16-5p、miR-101a-3p、miR-218-5p及miR-27b-3p——显著上调；而另有4种不同的miRNA——miR-150-5p、let-7b-5p、let-7c-5p及miR-181b-5p——仅在胶原酶诱导的出血性脑卒中大鼠中出现上调。综上，本研究鉴定出了出血性脑卒中大鼠血浆中特异性表达的部分miRNA，并指出精准测量时间节点对于提升miRNA作为脑卒中生物标志物的应用可靠性至关重要。