Rift Valley fever virus activates multiple cell death pathways in neurons

Area of Science:

• Neuroscience
• Virology
• Immunology

Background:

• Viral encephalitis, including Rift Valley fever virus (RVFV) encephalitis, causes significant neuronal injury and death.
• Late-onset encephalitis due to RVFV is an understudied but critical outcome.
• Previous studies established a rodent model of lethal RVF encephalitis, highlighting immune dysregulation and blood-brain barrier breakdown.

Purpose of the Study:

• To investigate the specific mechanisms of neuronal cell death induced by RVFV infection.
• To identify the primary cell death pathways activated in neurons following RVFV exposure.
• To provide a foundation for developing neuroprotective therapeutics against RVFV encephalitis.

Main Methods:

• Utilized both in vivo (rodent model) and in vitro (primary cortical neurons) experimental systems.
• Analyzed brain tissue from infected animals for proteins associated with apoptosis, pyroptosis, and necroptosis.
• Employed immunoblotting, immunocytochemistry, and in-cell western assays on infected primary neurons.

Main Results:

• RVFV infection led to increased levels of proteins linked to apoptosis, pyroptosis, and necroptosis in the brains of deceased animals.
• Primary cortical neurons were highly susceptible to infection by both pathogenic and attenuated RVFV strains.
• RVFV infection activated multiple cell death pathways in neurons, resulting in cell death, even with an attenuated strain.

Conclusions:

• RVFV infection induces neuronal death through the activation of multiple programmed cell death pathways.
• These findings elucidate critical mechanisms of neuronal damage in RVFV encephalitis.
• This research is vital for designing targeted therapies to preserve neuronal integrity during viral encephalitis.