Ⅰ型干扰素信号通路在N-乙酰半胱氨酸抗仔猪流行性腹泻病毒感染中的作用研究

Nowadays, intestinal injury caused by various factors brings about great losses of pig industry, thereinto, porcine epidemic diarrhea virus (PEDV) infection is of great harm. Our recent study shows that N-acetylcysteine (NAC) has antiviral effects on PEDV and could induce expressions of IFN-α/β and several antiviral proteins, but the related molecular mechanisms are still unclear. In this study, using weaned piglets as animal model, expressions of key molecules and genes of typeⅠinterferon signaling are assayed with Western blot and qPCR. Through these experiments, we study NAC’s roles in activating typeⅠinterferon-mediated JAK/STAT signaling pathway and inner links between typeⅠinterferon signaling and NAC’s effects against PEDV infection, thereby to explore the role of typeⅠinterferon signaling in the protective effects of NAC on PEDV infection in piglets. Novel academic viewpoints are expected to form in regard to the linkage among NAC- typeⅠinterferon signaling - anti-PEDV action. These results will provide theoretical basis for establishing new disease-resistance nutrition technologies in piglets and confer new clues for the prevention of porcine epidemic diarrhea.

当前，各种因素导致的猪肠道损伤给养猪业造成了巨大损失，其中猪流行性腹泻病毒（PEDV）感染危害极大。我们前期的研究显示，N-乙酰半胱氨酸（NAC）体外具有抗PEDV作用、并可诱导IFN-α/β与几种抗病毒蛋白表达，但有关分子机制尚不清楚。项目以断奶仔猪为动物模型，使用Western blot和实时定量PCR技术检测Ⅰ型干扰素信号通路关键分子及其基因的表达，研究NAC 在Ⅰ型干扰素介导的JAK/STAT信号通路激活中的作用、Ⅰ型干扰素信号通路与NAC抗PEDV感染的内在关系，探讨Ⅰ型干扰素信号通路在NAC抗仔猪流行性腹泻病毒感染中的作用，以期在NAC—Ⅰ型干扰素信号通路—抗PEDV感染的联系方面形成新的学术观点，为建立仔猪抗病营养新技术、防控猪流行性腹泻提供理论依据。

当前，各种因素导致的猪肠道损伤给养猪业造成了巨大损失，其中猪流行性腹泻病毒（PEDV）感染危害极大。我们前期的研究显示，N-乙酰半胱氨酸（NAC）体外具有抗PEDV作用、并可诱导IFN-α/β与几种抗病毒蛋白表达，但有关分子机制尚不清楚。项目采用猪小肠上皮细胞体外培养实验与以断奶仔猪为动物模型的体内实验相结合、使用Western blot和实时定量PCR技术检测Ⅰ型干扰素信号通路关键分子及其基因的表达、利用特异性抑制剂靶向阻断Ⅰ型干扰素信号通路等方法，研究NAC在Ⅰ型干扰素信号通路中的作用。研究结果表明，NAC促进PEDV感染IPEC-1的生长，调控PEDV感染IPEC-1细胞的生长、增殖、炎症反应等相关基因的表达，并通过激活I型干扰素信号通路抑制PEDV对IPEC-1细胞的感染。口服PEDV可以提高仔猪腹泻率，降低生长性能。灌服NAC可以改善PEDV感染仔猪肠道的吸收功能，缓解PEDV感染导致的肠黏膜损伤。通过调节小肠IFN-α和IFN-β基因表达，上调小肠I-FABP和villin，下调小肠OAS1、OAS2、IFIT1、IFIT2、IFIT3、MX1和GCNT3基因表达，对PEDV感染仔猪肠道完整性和吸收功能发挥保护作用。为建立仔猪抗病营养新技术、防控猪流行性腹泻提供理论依据。