College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, P. R. China.
Metallomics. 2020 Apr 1;12(4):562-571. doi: 10.1039/c9mt00302a. Epub 2020 Mar 3.
Multiple tissue necrosis is one of the morphological features of selenium deficiency-mediated injury. MicroRNA (miRNA) participates in the occurrence and development of necroptosis by regulating target genes. Necroptosis is a programmed form of necrosis, and it is closely related to lipopolysaccharide (LPS)-induced injury. Our aim was to investigate whether Se deficiency can promote tracheal injury caused by LPS through miRNA-induced necroptosis. By establishing models of tracheal injury in Se-deficient chickens, we verified the targeting relationship between chicken-derived miR-16-5p and PI3K through bioinformatics, qRT-PCR and WB analyses, and we measured the changes in the expression of genes related to the PI3K/AKT pathway, RIP3/MLKL pathway and MAPK pathway and of heat shock proteins. Under the condition of Se deficiency, the following results were observed: PI3K/AKT expression decreased with the upregulation of miR-16-5p, the expression of necroptosis-related factors (TNF-α, RIP1, FADD, RIP3 and MLKL) increased, and the expression of Caspase 8 significantly decreased (p < 0.05). Light microscopy observations indicated that cell necrosis was the main pathological change due to Se deficiency injury in the tracheal epithelium. The MAPK pathway was activated, and HSP expression was upregulated, indicating that the MAPK pathway and HSPs are both involved in Se deficiency-mediated necroptosis. In addition, Se deficiency promoted the expression of necroptosis-related genes in LPS-treated chickens (p < 0.05), and the pathological changes of cell necrosis were more obvious. In conclusion, we demonstrated that Se deficiency regulates the miR-16-5p-PI3K/AKT pathway and exacerbates LPS-induced necroptosis in chicken tracheal epithelial cells by activating necroptosis-related genes.
多组织坏死是硒缺乏介导损伤的形态学特征之一。MicroRNA（miRNA）通过调控靶基因参与细胞坏死的发生和发展。细胞坏死是一种程序性的坏死形式，与脂多糖（LPS）诱导的损伤密切相关。本研究旨在探讨硒缺乏是否通过 miRNA 诱导的细胞坏死促进 LPS 诱导的气管损伤。通过建立硒缺乏鸡气管损伤模型，我们通过生物信息学、qRT-PCR 和 WB 分析验证了鸡源性 miR-16-5p 与 PI3K 的靶向关系，并检测了与 PI3K/AKT 通路、RIP3/MLKL 通路和 MAPK 通路以及热休克蛋白相关的基因表达变化。在硒缺乏条件下，观察到以下结果：PI3K/AKT 表达下降，miR-16-5p 上调，坏死相关因子（TNF-α、RIP1、FADD、RIP3 和 MLKL）表达增加，Caspase 8 表达显著降低（p<0.05）。光镜观察表明，细胞坏死是由于硒缺乏损伤导致气管上皮细胞的主要病理变化。MAPK 通路被激活，HSP 表达上调，表明 MAPK 通路和 HSPs 均参与硒缺乏介导的细胞坏死。此外，硒缺乏促进 LPS 处理鸡中坏死相关基因的表达（p<0.05），细胞坏死的病理变化更加明显。综上所述，本研究表明，硒缺乏通过激活坏死相关基因调节 miR-16-5p-PI3K/AKT 通路，加剧 LPS 诱导的鸡气管上皮细胞坏死。
