Down-Regulation of IRF6 Protects Cortical Neurons Against Traumatic Neuronal Injury Through Activating Akt-eNOS...

Area of Science:

• Neuroscience
• Molecular Biology
• Cell Biology

Background:

• Interferon regulatory factor 6 (IRF6) is a transcription factor whose function is largely unknown.
• IRF6 expression increases after traumatic brain injury (TBI) and may promote neuronal apoptosis under oxidative stress.

Purpose of the Study:

• To investigate the role of IRF6 in traumatic neuronal injury (TNI) in primary mouse cortical neurons.
• To elucidate the molecular mechanisms underlying IRF6's function in neuronal injury.

Main Methods:

• Primary mouse cortical neurons were subjected to TNI.
• IRF6 expression was analyzed post-TNI.
• IRF6 was knocked down using small interfering RNA (siRNA).
• Neuronal viability, apoptosis (TUNEL staining, caspase-3 activity), lipid peroxidation, antioxidative enzyme activity, and inflammatory cytokine expression were assessed.
• Western blotting was used to evaluate the Akt-eNOS pathway.

Main Results:

• IRF6 expression significantly increased within 48 hours after TNI, peaking at 24 hours.
• IRF6 knockdown attenuated neuronal viability loss and lactate dehydrogenase release.
• IRF6 knockdown reduced neuronal apoptosis and caspase-3 activity.
• Downregulation of IRF6 inhibited lipid peroxidation, enhanced antioxidative enzyme activity, and modulated inflammatory cytokine expression.
• IRF6 knockdown increased Akt and eNOS phosphorylation.
• Inhibition of the Akt-eNOS pathway partially reversed the protective effects of IRF6 knockdown.

Conclusions:

• IRF6 plays a critical role in mediating neuronal damage after TNI.
• Downregulation of IRF6 confers neuroprotection against TNI.
• IRF6 knockdown exerts protective effects through Akt-eNOS pathway-mediated antioxidative and anti-inflammatory activities.