College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China.
College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Vet Microbiol. 2019 May;232:1-12. doi: 10.1016/j.vetmic.2019.03.028. Epub 2019 Mar 30.
Porcine epidemic diarrhea virus (PEDV) is a member of Coronavirus, which causes severe watery diarrhea in piglets with high morbidity and mortality. ROS and p53 play key roles in regulating many kinds of cell process during viral infection, however, the exact function in PEDV-induced apoptosis remains unclear. In this study, the pro-apoptotic effect of PEDV was examined in Vero cells and we observed that PEDV infection increased MDM2 and CBP, promoted p53 phosphorylation at serine 20 and, promoted p53 nuclear translocation, leading to p53 activation in Vero cells. Treatment with the p53 inhibitor PFT-α could significantly inhibit PEDV-induced apoptosis. We also observed PEDV infection induced time-dependent ROS accumulation. Treatment with antioxidants, such as pyrrolidine dithiocarbamate (PDTC) or N-acetylcysteine (NAC), significantly inhibited PEDV-induced apoptosis. Moreover, further inhibition tests were established to prove that p53 was regulated by ROS in PEDV-induced apoptosis. In addition, we also found that p38 MAPK and SAPK/JNK were activated in PEDV-infected Vero cells. However, treatment with the p38 MAPK inhibitor SB203580, and the SAPK/JNK inhibitor SP600125 reversed PEDV-induced apoptosis. Taken together, the results of this study demonstrate that activated p53 and accumulated ROS participated in PEDV-induced apoptosis and p53 could be regulated by ROS during PEDV infection. Activated p38 MAPK and SAPK/JNK exerted no influence on PEDV-induced apoptosis. These findings provide new insights into the function of p53 and ROS in the interaction of PEDV with Vero cells.
猪流行性腹泻病毒（PEDV）是冠状病毒科的一员，可引起仔猪严重的水样腹泻，发病率和死亡率都很高。ROS 和 p53 在病毒感染过程中对多种细胞过程的调节中起着关键作用，然而，其在 PEDV 诱导的细胞凋亡中的确切功能尚不清楚。在本研究中，我们在 Vero 细胞中检测了 PEDV 的促凋亡作用，观察到 PEDV 感染增加了 MDM2 和 CBP，促进了 p53 在丝氨酸 20 位的磷酸化，并促进了 p53 核转位，导致 Vero 细胞中的 p53 激活。用 p53 抑制剂 PFT-α处理可显著抑制 PEDV 诱导的细胞凋亡。我们还观察到 PEDV 感染诱导了时间依赖性的 ROS 积累。抗氧化剂如吡咯烷二硫代氨基甲酸盐（PDTC）或 N-乙酰半胱氨酸（NAC）处理可显著抑制 PEDV 诱导的细胞凋亡。此外，进一步的抑制试验证明了 p53 是由 ROS 调节的，参与了 PEDV 诱导的细胞凋亡。此外，我们还发现 p38 MAPK 和 SAPK/JNK 在 PEDV 感染的 Vero 细胞中被激活。然而，用 p38 MAPK 抑制剂 SB203580 和 SAPK/JNK 抑制剂 SP600125 处理可逆转 PEDV 诱导的细胞凋亡。总之，本研究的结果表明，激活的 p53 和积累的 ROS 参与了 PEDV 诱导的细胞凋亡，并且在 PEDV 感染过程中 p53 可以被 ROS 调节。激活的 p38 MAPK 和 SAPK/JNK 对 PEDV 诱导的细胞凋亡没有影响。这些发现为 p53 和 ROS 在 PEDV 与 Vero 细胞相互作用中的功能提供了新的见解。
