Department of Neurosurgery, The Second Hospital of Hebei Medical University, 215 Heping West Road, 050000, Shijiazhuang, Hebei, China.
Institute of Military Cognition and Brain Science Research, Academy of Military Medical Sciences, Beijing, China.
Genes Genomics. 2022 Apr;44(4):477-486. doi: 10.1007/s13258-021-01210-z. Epub 2022 Jan 10.
Microglia are important immune cells, which can be induced by lipopolysaccharide (LPS) into M1 phenotype that express pro-inflammatory cytokines. Some studies have shown that microRNAs play critical roles in microglial activation.
This study was designed to investigate the role of miR-200c-3p in regulating inflammatory responses of LPS-treated BV2 cells.
The expression of miR-200c-3p in BV2 cells was detected by real-time PCR. Receptor-interacting protein 2 (RIP2) was predicted as a target gene of miR-200c-3p. Their relationship was verified by dual-luciferase reporter assay. The function of miR-200c-3p and RIP2 in microglial polarization and NF-κB signaling was further evaluated.
LPS treatment reduced miR-200c-3p expression in a dose-dependent and time-dependent manner in BV2 cells. LPS treatment increased the expression of M1 phenotype markers inducible nitric oxide synthase (iNOS) and major histocompatibility complex class (MHC)-II, promoted the release of pro-inflammatory cytokines interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α, and enhanced the nuclear translocation and phosphorylation of nuclear factor-kappaB (NF-κB) p65. Reversely, miR-200c-3p mimics down-regulated the levels of these inflammatory factors. Furthermore, RIP2 was identified to be a direct target of miR-200c-3p. RIP2 knockdown had a similar effect to miR-200c-3p mimics. Overexpression of RIP2 eliminated the inhibitory effect of miR-200c-3p on LPS-induced M1 polarization and NF-κB activation in BV2 cells.
MiR-200c-3p mimics suppressed LPS-induced microglial M1 polarization and NF-κB activation by targeting RIP2. MiR-200c-3p/RIP2 might be a potential therapeutic target for the treatment of neuroinflammation-associated diseases.
小胶质细胞是重要的免疫细胞，可被脂多糖（LPS）诱导为表达促炎细胞因子的 M1 表型。一些研究表明，microRNAs 在小胶质细胞激活中发挥关键作用。
本研究旨在探讨 miR-200c-3p 在调节 LPS 处理的 BV2 细胞炎症反应中的作用。
通过实时 PCR 检测 BV2 细胞中 miR-200c-3p 的表达。预测受体相互作用蛋白 2（RIP2）是 miR-200c-3p 的靶基因。通过双荧光素酶报告基因检测验证它们之间的关系。进一步评估 miR-200c-3p 和 RIP2 对小胶质细胞极化和 NF-κB 信号通路的作用。
LPS 处理以剂量和时间依赖的方式降低 BV2 细胞中 miR-200c-3p 的表达。LPS 处理增加了诱导型一氧化氮合酶（iNOS）和主要组织相容性复合体（MHC）-II 等 M1 表型标志物的表达，促进了促炎细胞因子白细胞介素（IL）-1β、IL-6 和肿瘤坏死因子（TNF）-α的释放，并增强了核因子-kappaB（NF-κB）p65 的核转位和磷酸化。相反，miR-200c-3p 模拟物下调了这些炎症因子的水平。此外，鉴定出 RIP2 是 miR-200c-3p 的直接靶标。RIP2 敲低具有与 miR-200c-3p 模拟物相似的作用。RIP2 的过表达消除了 miR-200c-3p 对 LPS 诱导的 BV2 细胞 M1 极化和 NF-κB 激活的抑制作用。
miR-200c-3p 模拟物通过靶向 RIP2 抑制 LPS 诱导的小胶质细胞 M1 极化和 NF-κB 激活。miR-200c-3p/RIP2 可能是治疗神经炎症相关疾病的潜在治疗靶点。
