Liu Yanfang, Li Yufeng, Zang Jiankun, Zhang Tianyuan, Li Yaojie, Tan Zefeng, Ma Dan, Zhang Tao, Wang Shiyong, Zhang Yusheng, Huang Lian, Wu Yousheng, Su Xuanlin, Weng Zean, Deng Die, Tsang Chi Kwan, Xu Anding, Lu Dan
Department of Neurology and Stroke Center (Y. Liu, Y. Li, J.Z., T.Z., Y.L., Z.T., Y.Z., L.H., Y.W., X.S., Z.W., D.D., A.X., D.L.), The First Affiliated Hospital of Jinan University, Guangzhou, China.
Clinical Neuroscience Institute (Y. Liu, Y. Li, J.Z., T.Z., Y.L., Z.T., Y.Z., L.H., Y.W., X.S., Z.W., D.D., C.K.T., A.X., D.L.), The First Affiliated Hospital of Jinan University, Guangzhou, China.
Circ Res. 2022 Mar 18;130(6):907-924. doi: 10.1161/CIRCRESAHA.121.319412. Epub 2022 Feb 22.
Acute ischemic stroke (AIS) is a leading cause of disability and mortality worldwide. Prediction of penumbra existence after AIS is crucial for making decision on reperfusion therapy. Yet a fast, inexpensive, simple, and noninvasive predictive biomarker for the poststroke penumbra with clinical translational potential is still lacking. We aim to investigate whether the CircOGDH (circular RNA derived from oxoglutarate dehydrogenase) is a potential biomarker for penumbra in patients with AIS and its role in ischemic neuronal damage.
CircOGDH was screened from penumbra of middle cerebral artery occlusion mice and was assessed in plasma of patients with AIS by quantitative polymerase chain reaction. Magnetic resonance imaging was used to examine the penumbra volumes. CircOGDH interacted with miR-5112 (microRNA-5112) in primary cortical neurons was detected by fluorescence in situ hybridization, RNA immunoprecipitation, and luciferase reporter assay. Adenovirus-mediated CircOGDH knockdown ameliorated neuronal apoptosis induced by (Gallus collagen, type IV, alpha IV) overexpression. Transmission electron microscope, nanoparticle tracking analysis, and Western blot were performed to confirm exosomes.
CircOGDH expression was dramatically and selectively upregulated in the penumbra tissue of middle cerebral artery occlusion mice and in the plasma of 45 patients with AIS showing a 54-fold enhancement versus noncerebrovascular disease controls. Partial regression analysis revealed that CircOGDH expression was positively correlated with the size of penumbra in patients with AIS. Sequestering of miR-5112 by CircOGDH enhanced expression to elevate neuron damage. Additionally, knockdown of CircOGDH significantly enhanced neuronal cell viability under ischemic conditions. Furthermore, the expression of CircOGDH in brain tissue was closely related to that in the serum of middle cerebral artery occlusion mice. Finally, we found that CircOGDH was highly expressed in plasma exosomes of patients with AIS compared with those in noncerebrovascular disease individuals.
These results demonstrate that CircOGDH is a potential therapeutic target for regulating ischemia neuronal viability, and is enriched in neuron-derived exosomes in the peripheral blood, exhibiting a predictive biomarker of penumbra in patients with AIS.
急性缺血性卒中（AIS）是全球致残和致死的主要原因。预测AIS后半暗带的存在对于决定再灌注治疗至关重要。然而，目前仍缺乏一种快速、廉价、简单且具有临床转化潜力的无创性预测生物标志物来评估卒中后的半暗带。我们旨在研究环状α-酮戊二酸脱氢酶（CircOGDH）是否为AIS患者半暗带的潜在生物标志物及其在缺血性神经元损伤中的作用。
从大脑中动脉闭塞小鼠的半暗带中筛选出CircOGDH，并通过定量聚合酶链反应在AIS患者的血浆中进行评估。采用磁共振成像检查半暗带体积。通过荧光原位杂交、RNA免疫沉淀和荧光素酶报告基因检测法检测CircOGDH与原代皮质神经元中微小RNA-5112（miR-5112）的相互作用。腺病毒介导的CircOGDH敲低可改善由IV型鸡胶原蛋白α4（Col4a4）过表达诱导的神经元凋亡。通过透射电子显微镜、纳米颗粒跟踪分析和蛋白质免疫印迹法来确认外泌体。
CircOGDH在大脑中动脉闭塞小鼠的半暗带组织以及45例AIS患者的血浆中显著且选择性地上调，与非脑血管疾病对照组相比增强了54倍。偏回归分析显示，AIS患者中CircOGDH的表达与半暗带大小呈正相关。CircOGDH对miR-5112的隔离增强了Col4a4的表达，从而加重神经元损伤。此外，CircOGDH敲低显著提高了缺血条件下神经元细胞的活力。此外，脑组织中CircOGDH的表达与大脑中动脉闭塞小鼠血清中的表达密切相关。最后，我们发现与非脑血管疾病个体相比，CircOGDH在AIS患者血浆外泌体中高表达。
这些结果表明，CircOGDH是调节缺血性神经元活力的潜在治疗靶点，在外周血中富含于神经元来源的外泌体中，是AIS患者半暗带的预测生物标志物。
