Negative regulation of SREBP-1/FAS signaling molecules activates the RIG-1/TBK1-mediated IFN-I pathway to inhibit BVDV replication

Antiviral Res. 2025 Jan:233:106054. doi: 10.1016/j.antiviral.2024.106054. Epub 2024 Dec 9.

Abstract

For many viruses, controlling the process of infection is largely dependent on the enzymes of the fatty acid synthesis (FAS) pathway. An appealing therapeutic target in antiviral research is fatty acid synthetase (FASN), a crucial enzyme in the FAS pathway. Bovine viral diarrhea, caused by the Bovine viral diarrhea virus (BVDV), is a significant viral infectious disease posing a substantial threat to global animal husbandry. Our study revealed that BVDV infection not only upregulates the expression of FAS-related enzymes in BT cells and the blood, liver, and spleen of mice but also markedly enhances the accumulation of lipid droplets, free fatty acids, and triglycerides. The FAS pathway plays a pivotal role throughout the entire BVDV replication cycle. Additionally, administration of the FASN inhibitor C75 and Acetyl CoA carboxylase-1 (ACC-1) inhibitor TOFA significantly reduced the viral content in both serum and organs of BVDV-infected mice, exhibiting inhibitory effects across diverse viral strains. Intriguingly, We found that RIG-1/TBK1-mediated IFN-I signaling inhibits SREBP-1/FAS and reduces BVDV replication. Conversely, targeting a few essential enzymes of SREBP-1/FAS also activates IFN-I signaling. More importantly, FASN inhibitor led to heightened expression of ISGs in mouse spleens by activating the RIG-1/TBK-1 pathway. These findings highlight that FASN inhibitors inhibit BVDV replication through the activation of the RIG-1/TBK-1 pathway to induce ISGs, and offering a novel therapeutic approach for combating BVDV. Thus, it is crucial to negatively regulate SREBP-1/FAS signaling molecules in order to create novel antiviral drugs that are safe, effective, and broad-spectrum.

Keywords: Antiviral drugs; Bovine viral diarrhea virus; Fatty acid synthetase; IFN-I; ISGs.

MeSH terms

  • Animals
  • Antiviral Agents / pharmacology
  • Bovine Virus Diarrhea-Mucosal Disease* / drug therapy
  • Bovine Virus Diarrhea-Mucosal Disease* / virology
  • Cattle
  • Cell Line
  • DEAD Box Protein 58 / metabolism
  • Diarrhea Viruses, Bovine Viral* / drug effects
  • Diarrhea Viruses, Bovine Viral* / physiology
  • Fatty Acid Synthases / antagonists & inhibitors
  • Fatty Acid Synthases / metabolism
  • Interferon Type I* / metabolism
  • Mice
  • Protein Serine-Threonine Kinases / metabolism
  • Signal Transduction* / drug effects
  • Sterol Regulatory Element Binding Protein 1* / metabolism
  • Virus Replication* / drug effects

Substances

  • Interferon Type I
  • Sterol Regulatory Element Binding Protein 1
  • Protein Serine-Threonine Kinases
  • DEAD Box Protein 58
  • Ddx58 protein, mouse
  • Fatty Acid Synthases
  • Antiviral Agents