天山堇菜提取物基于NLRP3/caspase-1/IL-1β信号通路改善哮喘小鼠气道炎症的作用及机制

Effect of Viola tianshanica Maxim extract on airway inflammation in asthmatic mice by NLRP3/caspase-1/IL-1βsignaling pathway and its mechanism

目的探究天山堇菜提取物(Viola tianshanica Maxim extract,VTME)改善哮喘小鼠气道炎症的作用及机制。方法BALB/c雌性小鼠,随机分为正常对照组、卵清白蛋白(OVA)模型组、VTME低、中、高剂量(80、160、320 mg·kg^(-1))组、阳性对照药地塞米松组(Dex,80 mg·kg^(-1))组。采用OVA致敏、激发的方法诱导哮喘模型。收集小鼠肺泡灌洗液(BALF)并对炎症细胞进行分类计数;采用ELISA法检测BALF中调节活化的正常T细胞表达和分泌因子(RANTES)、IFN-γ及TNF-α含量,肺组织中TNF-α、MCP-1、IFN-γ、IL-17含量以及血清中IgE、嗜酸性粒细胞趋化因子(eotaxin)水平;采用HE染色观察肺组织病理改变;采用qRT-PCR法和Western blot法分别检测肺组织NLRP3 mRNA表达水平及GSDMD、caspase-1、IL-1β、NLRP3蛋白表达水平。结果VTME能明显降低哮喘小鼠BALF中各类炎症细胞数量及TNF-α、IFN-γ、Rantes的含量,降低肺组织MCP-1、IFN-γ、IL-17的含量以及血清Eotaxin水平;改善哮喘小鼠肺组织病理状态;降低肺组织NLRP3 mRNA水平以及caspase-1、GSDMD、IL-1β和NLRP3蛋白表达水平。结论VTME可能通过抑制NLRP3/caspase-1/IL-1β信号通路对OVA诱导的哮喘小鼠模型发挥保护作用。

Aim To investigate the effect of Viola tianshanica Maxim extract(VTME)on airway inflammation in asthmatic mice and the underlying mechanism.Methods BALB/c mice were divided into the OVA model group,VTME groups(80,160 and 320 mg·kg^(-1)),Dex group(dexamethasone,80 mg·kg^(-1))and the control group.OVA and aluminum hydroxide suspension were adopted to induce asthma models.Mouse alveolar lavage fluid(BALF)was collected,then the inflammatory cells in BALF were sorted and numbered.The concentrations of TNF-α,IFN-γand Rantes in BALF,the contents of TNF-α,IFN-γ,IL-17 and MCP-1 in lung,and the concentrations of IgE and Eotaxin in serum were examined by Elisa methods seperately.The pathological changes of lung tissue were inspected by HE staining.The levels of NLRP3 mRNA expression and caspase-1,GSDMD,IL-1βand NLRP3 protein expression in lung tissue were determined by qRT-PCR and Western blot.Results VTME obviously inhibited the number of total cells and the production of NEU,EOS,LYM,Mon and Bas in BALF.VTME also obviously decreased the levels of TNF-α,IFN-γand Rantes in BALF,the contents of inflammatory factors MCP-1,IFN-γand IL-17 in lung tissue and the levels of IgE and eotaxin in serum.The pathological status of lung tissue was obviously improved.In lung tissue,the level of NLRP3 mRNA expression obviously declined,and the contents of NLRP3,caspase-1,GSDMD and IL-1βprotein expression were also obviously reduced.Conclusions VTME has a notable protective effect on asthmatic mice,and its mechanism is likely due to the restriction of NLRP3/caspase-1/IL-1βsignaling pathway.