Neuroinvasive virus facilitates viral replication by employing lipid droplets to reduce arachidonic acid-induced ferroptosis

Lipids have been previously implicated in the lifecycle of neuroinvasive viruses. However, the role of lipids in programmed cell death (PCD) and the relationship between PCD and lipid droplets (LDs) in neuroinvasive virus infection remains unclear. Here, we found that the infection of neuroinvasive virus, such as rabies virus (RABV) and encephalomyocarditis virus (EMCV) could enhance the LD formation in N2a cells, and decreasing LDs production by targeting diacylglycerol acyltransferase (DGAT) could suppress viral replication. The lipidomics analysis revealed that arachidonic acid (AA) was significantly increased after reducing LD formation by restricting DGAT, and AA was further demonstrated to induce ferroptosis to inhibit neuroinvasive virus replication. Moreover, lipid peroxidation and viral replication inhibition could be significantly alleviated by a ferroptosis inhibitor, ferrostatin-1, indicating that AA affected neuroinvasive virus replication mainly through inducing ferroptosis. Furthermore, AA was demonstrated to activate the Acyl-CoA synthetase long-chain family member 4 (ACSL4) - Lysophosphatidylcholine Acyltransferase 3 (LPCAT3) - Cytochrome P450 Oxidoreductase (POR) axis to induce ferroptosis. Our findings highlight novel cross-talks among viral infection, LDs and ferroptosis for the first time, providing a potential target for antiviral drug development.