Respiratory viruses induce ferroptosis-like features in lung epithelial cells

During infection, viruses can modulate various regulated cell death (RCD) mechanisms to evade host immunity and enhance replication. However, less is known about how viruses alter the recently discovered RCD ferroptosis, which is characterized by an iron-dependent accumulation of lipid peroxidation and mitochondrial fragmentation. Influenza A virus (IAV) H1N1 and human adenovirus type C5 (HAdV-C5) are two common causes of respiratory infections of the upper and lower respiratory tract and can lead to severe illness. While IAV has been shown to induce ferroptosis to support its replication, less is known whether this is also true for HAdV-C5. Here we perform a comparative study investigating ferroptosis features during IAV H1N1 and HAdV-C5 infections using alveolar (A549) and bronchial (BEAS-2B) epithelial cells. Our data reveal that HAdV-C5, similar to H1N1, induces lipid peroxidation in a time-dependent manner, which is partially suppressed in the presence of the ferroptosis inhibitor ferrostatin-1 (Fer-1). Strikingly, HAdV-C5 infections do not lead to changes in ferritin protein levels, which is responsible for iron storage. Furthermore, both H1N1 and HAdV-C5 infections trigger a profound mitochondrial network remodeling, comparable to that induced by the ferroptosis inducer RSL3, with effects varying by cell type and infection stage. These findings suggest that HAdV-C5, just like H1N1, can activate ferroptosis-like processes, highlighting a potential role for lipid peroxidation and mitochondrial alterations in adenoviral pathogenesis. Understanding this mechanism may uncover new therapeutic targets for viral respiratory infections.