氧化应激对PRRSV致PAM细胞TLR3/NF-κB分子转录的影响

Effect of Oxidative Stress on Transcription of TLR3/NF-κB Molecules in PRRSV Infected PAM

为探讨氧化应激对猪繁殖与呼吸综合征病毒(PRRSV)感染猪肺泡巨噬细胞(PAM)TLR3/NF-κB信号分子转录的影响,体外分离培养PAM,分为对照组、PRRSV感染组、抗氧化剂NAC+PRRSV组,促氧化剂H2O2+RRRSV组。分别在培养6、12、24、48、72h收集细胞,观察各组的细胞病变、real-time PCR检测PRRSV、TLR3、TRIF和NF-κB mRNA转录量的变化。结果显示,PRRSV感染组PRRSV、TLR3、TRIF及NF-κB mRNA的转录量与对照组相比随感染时间的延长显著升高(P<0.05),48h达到最大值;NAC处理接毒组各信号分子mRNA的转录量比PRRSV感染组同时间点略低;H_2O_2处理接毒组比PRRSV感染组的略高。结果表明,氧化应激可增强PRRSV致PAM细胞TLR3/NF-κB分子mRNA的转录量,NF-κB的活化可能是PRRSV导致细胞损伤的机制之一。

To explore the effect of oxidative stress on transcription of TLR3/NF-κB signaling pathway induced by porcine reproductive and respiratory syndrome virus（PRRSV）infected pulmonary alveolar macrophage（PAM）.The PAM were isolated aseptically and divided into four groups,pretreated PAM with oxidants and antioxidants before PRRSV infection groups,PRRSV-infected group and the uninfected PAM as control group and cultured in vitro.The PAM were collected at 6,12,24,48 and 72hours after infection.The cell pathogenic effect（CPE）was observed in the experimental groups and the control group at all time points;the mRNA transcription of PRRSV,TLR3,TRIF and NF-κB in different groups were detected by real-time PCR.The results showed that the mRNA levels of PRRSV,TLR3,TRIF and NF-κB in PRRSVinfected group were significantly higher compared with the control group over time（P〈0.05）and the maximum was 48hpi;In NAC treated group,the mRNA levels of PRRSV,TLR3,TRIF and NF-κB were slightly lower than that in PRRSV-infection group;pretreatment oxidative stress with specific agonist H2O2,the mRNA transcription of PRRSV,TLR3,TRIF and NF-κB were higher.The results indicated that oxidative stress augments the mRNA levels of TLR3/NF-κB molecule in PAM infected with PRRSV,the activation of NF-κB may be one of the significant aspect of PRRSV pathogenesis.