香烟烟雾对大鼠肺组织及血清中抗菌肽LL-37表达及翻译后修饰的影响

Effects of cigarette smoke on expression and post-translational modification of cathelicidin LL-37 in lung tissue and serum of rats

目的 探讨香烟暴露对大鼠肺组织及血清中抗菌肽LL-37翻译后瓜氨酸化修饰的影响。方法 应用香烟暴露法建立大鼠动物模型,根据不同暴露时长分为低、中、高暴露组,应用ELISA法检测不同香烟暴露强度大鼠肺组织及血清中白介素-8 (interleukin-8,IL-8)和肿瘤坏死因子α (tumor necrosis factor-α,TNF-α)水平、抗菌肽和肽酰精氨酸脱亚氨酶(peptidylarginine deiminase,PAD)-2和PAD-4水平,应用比色法测定不同香烟暴露强度大鼠肺组织及血清中瓜氨酸化蛋白水平。结果 香烟暴露可诱导大鼠肺组织及血清中炎症因子IL-8和TNF-α及抗菌肽水平升高,且与香烟暴露强度呈正相关;香烟暴露可引起肺组织和血清中瓜氨酸化蛋白水平升高,但并未引起PAD2和PAD4表达水平升高。结论 香烟暴露加重肺组织和血清中的炎症反应,引起抗菌肽表达的升高,并可能同时使其瓜氨酸化水平升高。

Objective To investigate the effects of cigarette exposure on the post-translational citrullinated modification of cathelicidin LL-37 in lung tissue and serum of rats.Methods Rat model was established by cigarette exposure and they were divided into the low,medium and high degree exposure groups according to the exposure duration.The levels of interleukin-8(IL-8),tumor necrosis factor(TNF)-α,antibacterial peptide and peptidylarginine deiminase(PAD)-2 and PAD-4 levels in lung tissue and serum of rats were measured by ELISA.The citrullinated protein levels in lung tissue and serum of rats were determined by colorimetric method.Results Cigarette exposure induced increased levels of inflammatory cytokines(IL-8,TNF-α)and antimicrobial peptides in lung tissue and serum of rats,and there was a positive correlation with cigarette exposure duration.Cigarette exposure caused elevated levels of citrullinated protein in lung tissue and serum,but did not increase the expression of PAD2 and PAD4.Conclusions Cigarette exposure aggravates the inflammatory reaction in lung tissue and serum,causing an increase in the expression of antibacterial peptides,and it may also increase the citrullination level.