Postinfection Metabolic Reprogramming of the Murine Trigeminal Ganglion Limits Herpes Simplex Virus-1 Replication

Herpes simplex virus type-1 (HSV-1) infections are known to alter the host metabolism for efficient propagation in vitro. However, in vivo metabolic perturbations upon prolonged HSV-1 infection remain poorly understood. We used high-resolution liquid chromatography coupled with mass spectrometry (LC-MS) and functional assays to determine the state of the trigeminal ganglion (TG) tissue metabolism upon prolonged corneal HSV-1 infection in a murine model. The metabolomics data indicated significant alterations in the host metabolic profile. After HSV-1 infection, the TG microenvironment assumed downregulation of central carbon metabolism and nucleotide synthesis pathways. We validated our observations using in vitro and ex vivo models through targeted inhibition of crucial metabolic polyamine pathways identified in our metabolomics screen. Our findings collectively suggested that HSV-1 infection altered the host metabolic product regulations that limit the energy and macromolecular precursors required for viral replication. IMPORTANCE The more severe ocular pathologies associated with HSV-1 infection are significant vision loss, ocular morbidity, and herpetic keratitis. The current clinical landscape lacks curative drugs and vaccines against HSV-1, a heavy burden associated with this neurotropic, ubiquitous pathogen. The virus is notoriously successful in establishing latency in the host TG, where it remains dormant with periodic reactivations in response to various stimuli like stress and immunosuppression. Metabolic perturbations in tissue microenvironment likely aid the virus in establishing its latent state along with subsequent reactivations yet remain poorly characterized. Here, we used mass spectrometry coupled with statistical data analysis to study the host metabolome in the TG during HSV-1 infection and identify metabolites that likely regulate infection.