Pediatric Neurology, Chengdu Women's and Children's Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610091, P.R. China.
Department of Neurology, Xiamen Children's Hospital of Fujian Province, Xiamen, Fujian 361006, P.R. China.
Mol Med Rep. 2021 Jan;23(1). doi: 10.3892/mmr.2020.11702. Epub 2020 Nov 20.
S100a8 serves an important role in cell differentiation and is abnormally expressed in common tumors, but there are few studies on the association between S100a8 and brain I/R injury. The present study aimed to investigate the role of S100a8 in oxygen‑glucose deprivation and reoxygenation (OGD/R)‑induced BV2 microglia cell injury, and to elucidate the potential underlying molecular mechanisms. BV2 cells were exposed to OGD/R to mimic ischemia/reperfusion (I/R) injury . S100a8 expression was detected via reverse transcription‑quantitative PCR and western blot analyses. Following transfection with short hairpin RNAs targeting S100a8, the levels of inflammatory cytokines and oxidative stress‑related factors were determined using commercial kits. Apoptosis was assessed using flow cytometric analysis and the expression levels of apoptosis‑related proteins were determined using western blot analysis. Subsequently, the mRNA and protein levels of Grb2‑associated binder 1 (GAB1) were assessed following S100a8 silencing. Immunoprecipitation (IP) was performed to verify the association between S100a8 and GAB1. The levels of inflammation, oxidative stress and apoptosis were assessed following GAB1 silencing, along with S100a8 silencing in BV2 cells subjected to OGD/R. The results indicated that exposure to OGD/R markedly upregulated S100a8 expression in BV2 cells. S100a8 silencing inhibited inflammation, oxidative stress and apoptosis, accompanied by changes in the expression of related proteins. The IP assay revealed a strong interaction between GAB1 and S100a8. In addition, GAB1 silencing reversed the inhibitory effects of S100a8 silencing on inflammation, oxidative stress and apoptosis in OGD/R‑stimulated BV2 cells. Taken together, the results of the present study demonstrated that S100a8 silencing alleviated inflammation, oxidative stress and the apoptosis of BV2 cells induced by OGD/R, partly by upregulating the expression of GAB1. Thus, these findings may potentially provide a novel direction to develop therapeutic strategies for cerebral I/R injury.
S100a8 在细胞分化中起着重要作用，并且在常见肿瘤中异常表达，但关于 S100a8 与脑 I/R 损伤之间的关系的研究较少。本研究旨在探讨 S100a8 在氧葡萄糖剥夺和再氧合（OGD/R）诱导的 BV2 小胶质细胞损伤中的作用，并阐明潜在的分子机制。通过氧葡萄糖剥夺模拟缺血/再灌注（I/R）损伤，将 BV2 细胞暴露于 OGD/R 中。通过逆转录定量 PCR 和 Western blot 分析检测 S100a8 的表达。用靶向 S100a8 的短发夹 RNA 转染后，使用商业试剂盒测定炎症细胞因子和氧化应激相关因子的水平。通过流式细胞术分析评估细胞凋亡，通过 Western blot 分析测定凋亡相关蛋白的表达水平。随后，沉默 S100a8 后评估 Grb2 相关结合物 1（GAB1）的 mRNA 和蛋白水平。进行免疫沉淀（IP）以验证 S100a8 与 GAB1 之间的关联。沉默 GAB1 后，评估 BV2 细胞中炎症、氧化应激和细胞凋亡的水平，同时评估 OGD/R 刺激下沉默 S100a8 后细胞中炎症、氧化应激和细胞凋亡的水平。结果表明，OGD/R 暴露可显著上调 BV2 细胞中 S100a8 的表达。沉默 S100a8 可抑制炎症、氧化应激和细胞凋亡，并伴有相关蛋白表达的变化。免疫沉淀试验显示 GAB1 和 S100a8 之间存在强烈的相互作用。此外，沉默 GAB1 可逆转 S100a8 沉默对 OGD/R 刺激的 BV2 细胞中炎症、氧化应激和细胞凋亡的抑制作用。综上所述，本研究结果表明，沉默 S100a8 可减轻 OGD/R 诱导的 BV2 细胞的炎症、氧化应激和细胞凋亡，部分是通过上调 GAB1 的表达。因此，这些发现可能为开发脑 I/R 损伤的治疗策略提供新的方向。
