Therapeutic Targeting of Endosome and Mitochondrial Reactive Oxygen Species Protects Mice From Influenza Virus Morbidity

Eunice E To; Jonathan R Erlich; Felicia Liong; Stella Liong; Raymond Luong; Osezua Oseghale; Mark A Miles; Paris C Papagianis; Kylie M Quinn; Steven Bozinovski; Ross Vlahos; Robert D Brooks; John J O'Leary; Doug A Brooks; Stavros Selemidis

doi:10.3389/fphar.2022.870156

Therapeutic Targeting of Endosome and Mitochondrial Reactive Oxygen Species Protects Mice From Influenza Virus Morbidity

Front Pharmacol. 2022 Mar 23:13:870156. doi: 10.3389/fphar.2022.870156. eCollection 2022.

Authors

Eunice E To^{1

2}, Jonathan R Erlich¹, Felicia Liong¹, Stella Liong¹, Raymond Luong³, Osezua Oseghale¹, Mark A Miles¹, Paris C Papagianis¹, Kylie M Quinn¹, Steven Bozinovski¹, Ross Vlahos¹, Robert D Brooks⁴, John J O'Leary^{5

6}, Doug A Brooks^{4

6}, Stavros Selemidis¹

Affiliations

¹ School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, Australia.
² F.M Kirby Neurobiology Centre, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States.
³ Department of Pharmacology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia.
⁴ Cancer Research Institute and School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia.
⁵ Sir Patrick Dun's Laboratory, Central Pathology Laboratory, Department of Histopathology Trinity College Dublin, Dublin, Ireland.
⁶ Molecular Pathology Laboratory, Coombe Women and Infants' University Hospital, Dublin, Ireland.

Abstract

There is an urgent need to develop effective therapeutic strategies including immunomodulators to combat influenza A virus (IAV) infection. Influenza A viruses increase ROS production, which suppress anti-viral responses and contribute to pathological inflammation and morbidity. Two major cellular sites of ROS production are endosomes via the NOX2-oxidase enzyme and the electron transport chain in mitochondria. Here we examined the effect of administration of Cgp91ds-TAT, an endosome-targeted NOX2 oxidase inhibitor, in combination with mitoTEMPO, a mitochondrial ROS scavenger and compared it to monotherapy treatment during an established IAV infection. Mice were infected with IAV (Hkx31 strain; 10⁴PFU/mouse) and 24 h post infection were treated with Cgp91ds-TAT (0.2 mg/kg), mitoTEMPO (100 μg) or with a combination of these inhibitors [Cgp91ds-TAT (0.2 mg/kg)/mitoTEMPO (100 μg)] intranasally every day for up to 2 days post infection (pi). Mice were euthanized on Days 3 or 6 post infection for analyses of disease severity. A combination of Cgp91ds-TAT and mitoTEMPO treatment was more effective than the ROS inhibitors alone at reducing airway and neutrophilic inflammation, bodyweight loss, lung oedema and improved the lung pathology with a reduction in alveolitis following IAV infection. Dual ROS inhibition also caused a significant elevation in Type I IFN expression at the early phase of infection (day 3 pi), however, this response was suppressed at the later phase of infection (day 6 pi). Furthermore, combined treatment with Cgp91ds-TAT and mitoTEMPO resulted in an increase in IAV-specific CD8⁺ T cells in the lungs. In conclusion, this study demonstrates that the reduction of ROS production in two major subcellular sites, i.e. endosomes and mitochondria, by intranasal delivery of a combination of Cgp91ds-TAT and mitoTEMPO, suppresses the severity of influenza infection and highlights a novel immunomodulatory approach for IAV disease management.

Keywords: NADPH oxidase; airway inflammation; endosome; inflammation; influenza A virus; lung inflammation; mitochondria; reactive oxygen.