Zhang Min, Fu Yi-Hao, Luo Yao-Wen, Gou Mao-Rong, Zhang Lei, Fei Zhou, Gao Da-Kuan
College of Life Sciences, Northwest University, Xi'an, Shaanxi, China; Department of Neurosurgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi, China.
Department of Neurosurgery, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi, China.
Neurosci Lett. 2023 Jan 10;793:137000. doi: 10.1016/j.neulet.2022.137000. Epub 2022 Dec 5.
Ischemic stroke is an acute brain disease with a high mortality rate. Currently, the only effective method is to restore the blood supply. But the inflammation and oxidative stress induced by this approach can damage the integrity of the endothelial system, which hampers the patient's outcome. d-allose has the biological activity to protect against ischemia-reperfusion injury, however, the underlying mechanism remains unclear. Here, brain microvascular endothelial cells (RBMECs) were used as the study material to establish an IR-injury model. Cell viability of RBMECs was suppressed after hypoxia/reoxygenation (H/R) treatment and significantly increased after d-allose supplementation. RNAseq results showed 180 differentially expressed genes (DEGs) between the therapy group (H/R + Dal) and the model group (H/R), of which 151 DEGs were restored to control levels by d-allose. Enrichment analysis revealed that DEGs were mainly involved in protein processing in endoplasmic reticulum. 6 DEGs in the unfolded protein response (UPR) pathway were verified by qRT-PCR. All of them were significantly down-regulated by d-allose, indicating that endoplasmic reticulum stress (ERS) was relieved. In addition, d-allose significantly inhibited the phosphorylation level of eIF2α, a marker of ERS. The downstream molecules of Phosphorylation of eIF2α, Gadd45a and Chac1, which trigger cycle arrest and apoptosis, respectively, were also significantly inhibited by d-allose. Thus, we conclude that d-allose inhibits the UPR pathway, attenuates eIF2α phosphorylation and ERS, restores the cell cycle, inhibits apoptosis, and thus enhances endothelial cell tolerance to H/R injury.
缺血性中风是一种死亡率很高的急性脑疾病。目前，唯一有效的方法是恢复血液供应。但这种方法所诱导的炎症和氧化应激会损害内皮系统的完整性，从而妨碍患者的预后。D-阿洛酮具有预防缺血再灌注损伤的生物活性，然而，其潜在机制仍不清楚。在此，以脑微血管内皮细胞（RBMECs）作为研究材料建立缺血再灌注损伤模型。缺氧/复氧（H/R）处理后RBMECs的细胞活力受到抑制，补充D-阿洛酮后显著增加。RNA测序结果显示治疗组（H/R + Dal）和模型组（H/R）之间有180个差异表达基因（DEG），其中151个DEG通过D-阿洛酮恢复到对照水平。富集分析显示DEG主要参与内质网中的蛋白质加工。通过qRT-PCR验证了未折叠蛋白反应（UPR）途径中的6个DEG。它们均被D-阿洛酮显著下调，表明内质网应激（ERS）得到缓解。此外，D-阿洛酮显著抑制了ERS标志物eIF2α的磷酸化水平。分别触发细胞周期停滞和凋亡的eIF2α磷酸化的下游分子Gadd45a和Chac1也被D-阿洛酮显著抑制。因此，我们得出结论，D-阿洛酮抑制UPR途径，减弱eIF2α磷酸化和ERS，恢复细胞周期，抑制细胞凋亡，从而增强内皮细胞对H/R损伤的耐受性。
