miR-599靶向TLR2对支原体肺炎小鼠肺组织的保护作用及机制

Protective effect and mechanism of miR-599 targeting TLR2 on lung tissue of mice with mycoplasma pneumonia

目的 探究miR-599对支原体肺炎小鼠肺组织的保护作用及可能机制。方法 SPF级BALB/c小鼠60只随机分成对照组(Control组)、支原体肺炎组(MP组)和miR-599组(miR-599组),每组20只。HE染色观察肺组织形态学变化;ELISA法检测血清炎症因子水平;TUNEL法检测肺组织细胞凋亡;Real time-qPCR检测小鼠肺组织miR-599水平;双荧光素酶报告基因实验检测miR-599是否靶向TLR2;Western blot检测肺组织TLR2/4-MyD88-NF-κB信号通路蛋白表达。结果 miR-599过表达改善小鼠肺组织形态,降低肺组织细胞凋亡水平,抑制血清炎症因子IL-1β、TNF-α和IL-6水平,降低TLR2/4-MyD88-NF-κB信号通路蛋白表达。结论miR-599改善支原体肺炎小鼠肺组织损伤,其作用机制可能与靶向抑制TLR2调节TLR2/4-MyD88-NF-κB信号通路有关。

Objective To explore the protective effect and possible mechanism of miR-599 on the lung tissue of mice with mycoplasma pneumonia. Methods Sixty SPF BALB/c mice were randomly divided into Control group, MP group and miR-599 group, with 20 mice in each group. The morphological changes of lung tissue were detected by HE staining. The serum inflammatory cytokines levels were detected by ELISA. The apoptosis of lung tissues was detected by TUNEL assay. The level of miR-599 in lung tissues of mice was detected by Real time-qPCR. The dual luciferase reporter gene assay was used to detect whether miR-599 targeted TLR2. The expression of TLR2/4-MyD88-NF-κB signaling pathway related proteins in lung tissues were detected by Western blot. Results The overexpression of miR-599 improved the pathological injury of lung tissue, decreased the apoptosis level of lung tissue cells, inhibited the levels of serum inflammatory cytokines IL-1β, TNF-α and IL-6, and decreased the protein expression of TLR2/4-MyD88-NF-κB signaling pathway. Conclusion miR-599 improves lung tissue injury in mice with mycoplasma pneumonia, and its mechanism may be related to the regulation of TLR2/4-MyD88-NF-κB signaling pathway by targeting TLR2 inhibition.