Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.
College of Animal Science, Tarim University, Alar, Xinjiang, China.
J Cell Physiol. 2020 May;235(5):4766-4777. doi: 10.1002/jcp.29354. Epub 2019 Oct 31.
Endometritis is an inflammatory change in the structure of the endometrium due to various causes and is a common cause of infertility. Studies have confirmed that microRNAs (miRNAs) play a key regulatory role in various inflammatory diseases. However, the miRNA-mediated mechanism of endometrial inflammation induced by lipopolysaccharides (LPS) remains unclear. In this study, real-time quantitative polymerase chain reaction, Western blot analysis, immunofluorescence and Rac family small GTPase 1 (Rac1) interference were used to reveal the overexpression of miR-488 in the LPS-induced bovine uterus, and the effect of protein kinase B κ-light chain enhancement of the nuclear factor-activated B cells (AKT/NF-κB) pathway in intimal epithelial cells. The results showed that the expression of inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in the experimental group was significantly lower than that in the control group when miR-488 was overexpressed. Similar results were observed in the expression levels of p-AKT, p-IKK, and p-p65 proteins. In addition, the dual-luciferase reporter system confirmed that miRNA-488 may directly target the 3'-untranslated region of Rac1. In turn, the expression of Rac1 was inhibited. Moreover, the nuclear translocation of NF-κB was inhibited, and meanwhile, the accumulation of reactive oxygen species (ROS) in the cells was reduced. Thus, we provide basic data for the negative regulation of miR-488 in LPS-induced inflammation by inhibiting ROS production and the AKT/NF-kB pathway in intimal epithelial cells.
子宫内膜炎是由于各种原因引起的子宫内膜结构的炎症性改变，是导致不孕的常见原因。研究证实，微小 RNA（miRNA）在各种炎症性疾病中发挥着关键的调节作用。然而，脂多糖（LPS）诱导的子宫内膜炎症的 miRNA 介导机制尚不清楚。在本研究中，实时定量聚合酶链反应、Western blot 分析、免疫荧光和 Rac 家族小 GTPase 1（Rac1）干扰用于揭示 LPS 诱导的牛子宫中 miR-488 的过表达，以及蛋白激酶 B κ-轻链增强的核因子 B 细胞激活（AKT/NF-κB）通路在子宫内膜上皮细胞中的作用。结果表明，当 miR-488 过表达时，实验组中白细胞介素-1β（IL-1β）、IL-6 和肿瘤坏死因子-α等炎症细胞因子的表达明显低于对照组。p-AKT、p-IKK 和 p-p65 蛋白的表达水平也观察到了类似的结果。此外，双荧光素酶报告系统证实，miR-488 可能直接靶向 Rac1 的 3'-非翻译区。反过来，Rac1 的表达受到抑制。此外，NF-κB 的核转位受到抑制，同时细胞内活性氧（ROS）的积累减少。因此，我们为 miR-488 通过抑制 ROS 产生和 AKT/NF-kB 通路在子宫内膜上皮细胞中负调控 LPS 诱导的炎症提供了基础数据。
