Cholestane-3β,5α,6β-Triol Inhibits Acid-Sensing Ion Channels and Reduces Acidosis-Mediated Ischemic Brain Injury

Area of Science:

• Neuroscience
• Pharmacology
• Biochemistry

Background:

• Acid-sensing ion channels (ASICs) activation by acidosis contributes to ischemic brain injury.
• Cholestane-3β,5α,6β-triol (Triol), a cholesterol metabolite, is an endogenous neuroprotectant with an unknown mechanism.
• This study investigates if Triol's neuroprotection involves ASIC inhibition.

Purpose of the Study:

• To determine if Triol inhibits ASICs.
• To elucidate the mechanism of Triol's neuroprotective effects.
• To evaluate Triol's therapeutic potential for stroke.

Main Methods:

• Whole-cell patch-clamp electrophysiology on cells expressing ASICs.
• Primary cultured mouse cortical neurons and ASIC knockout mice models.
• Middle cerebral artery occlusion (MCAO) model for ischemic brain injury.

Main Results:

• Triol inhibits ASIC1a and ASIC3, but not ASIC1β or ASIC2a.
• Inhibition is subunit-dependent, use-dependent, and pH/voltage-independent.
• Triol protects against acidosis-induced neuronal injury and MCAO-induced brain injury in an ASIC1a-dependent manner.

Conclusions:

• Triol is a novel inhibitor of ASICs.
• Triol demonstrates potential as a pharmacological tool for ASIC research.
• Triol may be developed as a therapeutic agent for stroke treatment.