ABSTRACT

1. Mycoplasma gallisepticum (MG) causes severe lung inflammation and cell damage by activating toll-like receptor (TLR) signalling, the nuclear factor-kappaB (NF-κB) pathway and pro-inflammatory cytokine gene expression. Baicalin (BA) is a flavonoid extracted from Scutellaria baicalensis, which possesses anti-inflammatory and anti-bacterial properties. This study investigated the effect of BA in MG-induced lung inflammation and its potential mechanism in MG-infected chicken embryo lungs and DF-1 cells.

2. The histopathological examination result showed that BA treatment alleviated MG-induced lung pathological changes. In addition, CCK-8 and cell cycle assays showed that BA treatment inhibited MG-induced cell proliferation and cell cycle progression in DF-1 cells.

3. The ELISA and RT-qPCR results demonstrated that BA treatment decreased the expression of interleukin-1beta (IL-1β), IL-6, and tumour necrosis factor-alpha (TNF-α) both in MG-infected chicken embryo lungs and DF-1 cells.

4. The results revealed that BA inhibited mRNA expression levels of toll-like receptor-6 (TLR6), myeloid differentiation primary response gene-88 (MyD88) and nuclear factor-κB (NF-κB), and the nuclear translocation of NF-κB-p65

5. In conclusion, the results showed that BA has a protective effect against MG-induced lung inflammation in chicken by inhibiting the TLR6-mediated NF-κB signalling.

抽象的

1.鸡毒支原体（MG）会引起严重的肺部炎症和通过激活Toll样受体（TLR）的信号，核因子-κB（NF-细胞损伤κ B）途径和促炎症细胞因子的基因表达。黄ical苷（BAicalin）是从黄cut提取的黄酮，具有抗炎和抗菌作用。这项研究调查了BA在MG诱导的肺部炎症中的作用及其在MG感染的鸡胚肺和DF-1细胞中的潜在机制。

2.组织病理学检查结果表明，BA治疗减轻了MG引起的肺部病理改变。此外，CCK-8和细胞周期试验表明，BA处理可抑制MG-1细胞中MG诱导的细胞增殖和细胞周期进程。

3. ELISA和RT-qPCR的结果表明，BA治疗白细胞介素-1β（IL-1的表达减少β），IL-6和肿瘤坏死因子-α（TNF- α）都在MG-感染的鸡胚胎肺和DF-1细胞。

4.结果表明BA抑制的mRNA表达水平的toll样受体6（TLR6），髓样分化初级应答基因88（MyD88的）和核因子κ B（NF- κ B），和核转NF- κ B-p65的

5.总之，结果表明，BA通过抑制TLR6介导的NF-κB信号传导对鸡的MG诱导的肺部炎症具有保护作用。