Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark; BRIDGE, Brain Research, Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
Neuropharmacology. 2019 May 15;150:100-111. doi: 10.1016/j.neuropharm.2019.02.035. Epub 2019 Mar 2.
Inhibition of postsynaptic density protein-95 (PSD-95) decouples N-methyl-d-aspartate (NMDA) receptor downstream signaling and results in neuroprotection after focal cerebral ischemia. We have previously developed UCCB01-144, a dimeric PSD-95 inhibitor, which binds PSD-95 with high affinity and is neuroprotective in experimental stroke. Here, we investigate the selectivity, efficacy and toxicity of UCCB01-144 and compare with the monomeric drug candidate Tat-NR2B9c. Fluorescence polarization using purified proteins and pull-downs of mouse brain lysates showed that UCCB01-144 potently binds all four PSD-95-like membrane-associated guanylate kinases (MAGUKs). In addition, UCCB01-144 affected NMDA receptor signaling pathways in ischemic brain tissue. UCCB01-144 reduced infarct size in young and aged male mice at various doses when administered 30 min after permanent middle cerebral artery occlusion, but UCCB01-144 was not effective in young male mice when administered 1 h post-ischemia or in female mice. Furthermore, UCCB01-144 was neuroprotective in a transient stroke model in rats, and in contrast to Tat-NR2B9c, high dose of UCCB01-144 did not lead to significant changes in mean arterial blood pressure or heart rate. Overall, UCCB01-144 is a potent MAGUK inhibitor that reduces neurotoxic PSD-95-mediated signaling and improves neuronal survival following focal brain ischemia in rodents under various conditions and without causing cardiovascular side effects, which encourages further studies towards clinical stroke trials.
抑制突触后密度蛋白-95（PSD-95）可使 N-甲基-D-天冬氨酸（NMDA）受体下游信号脱偶联，导致局灶性脑缺血后神经保护。我们之前开发了 UCCB01-144，一种二聚体 PSD-95 抑制剂，它与 PSD-95 具有高亲和力，并在实验性中风中具有神经保护作用。在这里，我们研究了 UCCB01-144 的选择性、疗效和毒性，并与单体药物候选物 Tat-NR2B9c 进行了比较。使用纯化蛋白进行荧光偏振和小鼠脑裂解物的下拉实验表明，UCCB01-144 可强力结合所有四种 PSD-95 样膜相关鸟苷酸激酶（MAGUK）。此外，UCCB01-144 影响缺血性脑组织中的 NMDA 受体信号通路。UCCB01-144 在雄性幼鼠和老年鼠中，在永久大脑中动脉闭塞后 30 分钟给予各种剂量时，可减少梗死面积，但在雄性幼鼠中，在缺血后 1 小时给予 UCCB01-144 或在雌性小鼠中，UCCB01-144 无效。此外，UCCB01-144 在大鼠短暂性中风模型中具有神经保护作用，与 Tat-NR2B9c 相反，高剂量的 UCCB01-144 不会导致平均动脉血压或心率发生显著变化。总体而言，UCCB01-144 是一种有效的 MAGUK 抑制剂，可减少神经毒性 PSD-95 介导的信号传递，并在各种条件下改善局灶性脑缺血后啮齿动物的神经元存活，而不会引起心血管副作用，这鼓励进一步进行临床试验。
