The Cholinergic Pathway and MitoK_ATP Induce UCP4 Expression Involved in Neuroprotection of FN Stimulation in Rats.

Area of Science:

• Neuroscience
• Cell Biology
• Biochemistry

Background:

• Electrical stimulation of the cerebellar fastigial nucleus (FN) reduces infarct size in rat models of middle cerebral artery occlusion.
• FN stimulation offers long-lasting brain injury protection, but the underlying mechanisms remain unclear.
• This study investigates the neuroprotective mechanism of FN stimulation, focusing on its role in brain injury recovery.

Purpose of the Study:

• To elucidate the neuroprotective mechanism of FN stimulation.
• To determine if FN stimulation involves cholinergic pathways and reactive oxygen species (ROS) production.
• To investigate the role of mitochondrial K⁺ _ATP channels and uncoupling protein 4 (UCP4) in FN-induced neuroprotection.

Main Methods:

• FN stimulation was applied to rats for 1 hour.
• UCP4 protein and mRNA levels were quantified using western blot, dot blot, and in situ hybridization.
• Carbachol and diazoxide were used to stimulate cholinergic pathways and open mitochondrial K⁺ _ATP channels, respectively, in cell cultures and in vivo.

Main Results:

• FN stimulation significantly increased UCP4 protein and mRNA levels.
• Carbachol administration induced UCP4 expression, which was attenuated by atropine, indicating cholinergic pathway involvement.
• Diazoxide-induced opening of mitochondrial K⁺ _ATP channels increased ROS production, leading to enhanced UCP4 expression and reduced ROS generation.

Conclusions:

• FN stimulation confers neuroprotection through the activation of cholinergic pathways.
• This activation increases ROS production via mitochondrial K⁺ _ATP channels.
• Increased ROS subsequently upregulates the expression of the neuroprotective protein UCP4.