Neuroprotective effects of targeting BET proteins for degradation with dBET1 in aged mice subjected to ischemic stroke
Neuroprotective effects of targeting BET proteins for degradation with dBET1 in aged mice subjected to ischemic stroke
复制标题
DOI：
10.1016/j.neuint.2019.03.004
复制
发表时间：
2019-07-01
影响因子：
4.2
通讯作者：
Candelario-Jalil, Eduardo
中科院分区：
文献类型：
--
作者：
DeMars, Kelly M.;Yang, Changjun;Candelario-Jalil, Eduardo
中风后的神经炎症显著促进神经元细胞死亡。布罗莫结构域和额外末端结构域（BET）蛋白对于炎性基因转录是必需的。BET蛋白（BRD 2、BRD 3、BRD 4和BRDT）具有不同的作用，包括染色质重塑、组蛋白乙酰转移酶活性，并作为招募转录因子的支架;它们将染色质重塑与转录偶联。BRD 2/4对中风诱导的神经炎症特别感兴趣，其有助于延迟细胞死亡，因为它们是NF-κ B依赖性基因转录所需的。我们假设用dBET 1（一种结合了高选择性BET抑制剂JQ 1和cereblon E3泛素连接酶配体的蛋白水解靶向嵌合体（PROTAC））靶向BET蛋白降解将减少缺血性卒中中的脑损伤。使雄性老龄小鼠（18-20月龄）经受大脑中动脉的永久闭塞，并接受媒介物或dBET 1（10 mg/kg; i. p.）在中风后的不同时间。在卒中诱导前（基线）和卒中诱导后24和48小时进行神经行为测试。在48 h时定量测定血小板体积。数据显示，BET降解显著降低了老年小鼠永久性局灶性脑缺血的梗死体积，这与促炎介质（包括TNF-α、CXCL 1、CXCL 10、CCL 2和基质金属蛋白酶-9）的脑水平降低有关。用dBET 1治疗显著减少了血脑屏障损伤和中性粒细胞向缺血脑中的浸润。重要的是，用BET降解剂dBET 1治疗导致中风引起的神经功能缺损显著改善。总的来说，这些数据表明BET蛋白是缺血性卒中神经保护的新靶点。
Neuroinflammation after stroke significantly contributes to neuronal cell death. Bromodomain and Extra Terminal Domain (BET) proteins are essential to inflammatory gene transcription. BET proteins (BRD2, BRD3, BRD4, and BRDT) have varied effects including chromatin remodeling, histone acetyltransferase activity, and as scaffolds to recruit transcription factors; they couple chromatin remodeling with transcription. BRD2/4 are of particularly interest to stroke-induced neuroinflammation that contributes to delayed cell death as they are required for NF-kappa B-dependent gene transcription. We hypothesized that targeting BET proteins for degradation with dBET1, a proteolysis targeting chimera (PROTAC) that combines the highly selective BET inhibitor JQ1 and a ligand for cereblon E3 ubiquitin ligase, will reduce brain injury in ischemic stroke. Male aged mice (18-20 months old) were subjected to permanent occlusion of the middle cerebral artery and received either vehicle or dBET1 (10 mg/kg; i.p.) at various times after stroke. Neurobehavioral tests were performed before (baseline) and at 24 and 48 h after stroke induction. Infarct volume was quantified at 48 h. Data showed that BET degradation significantly reduced infarct volume in permanent focal cerebral ischemia in aged mice, and this was associated with reduced brain levels of pro-inflammatory mediators including TNF-alpha, CXCL1, CXCL10, CCL2, and matrix metalloproteinase-9. Treatment with dBET1 significantly reduced blood-brain barrier damage and infiltration of neutrophils into the ischemic brain. Importantly, treatment with the BET degrader dBET1 resulted in a significant improvement in stroke-induced neurological deficits. Collectively, these data indicate that BET proteins are a novel target for neuroprotection in ischemic stroke.