Validation of Hv₁ channel functions in BV2 microglial cells using small molecule modulators

Area of Science:

• Neuroscience
• Immunology
• Cell Biology

Background:

• Microglia are key brain immune cells with dual roles in damage and repair.
• Dysregulated microglial activation contributes to secondary brain injury.
• Voltage-gated proton channels (Hv1) are expressed in microglia and influence their activation state.

Purpose of the Study:

• To investigate the role of microglial Hv1 channels in neuroinflammation.
• To characterize the effects of a novel Hv1 activator (S-023-0515) and an inhibitor (YHV98-4).
• To validate Hv1 as a therapeutic target for inflammatory brain conditions.

Main Methods:

• Utilized lipopolysaccharide (LPS)-induced neuroinflammation model in BV2 microglial cells.
• Administered Hv1 inhibitor YHV98-4 and Hv1 activator S-023-0515.
• Assessed levels of proinflammatory cytokines (TNF-α, IL-6, iNOS), microglial polarization, phagocytosis, and reactive oxygen species (ROS).
• Analyzed the involvement of NF-κB signaling pathway.

Main Results:

• YHV98-4 treatment reduced proinflammatory mediators in LPS-stimulated microglia.
• S-023-0515 increased M1 polarization, proinflammatory mediators, phagocytosis, and mitochondrial ROS.
• Both compounds modulated NF-κB phosphorylation, indicating pathway involvement.
• Hv1 inhibition demonstrated neuroprotective effects, while activation was neurotoxic in this model.

Conclusions:

• Hv1 channels play a critical role in regulating microglial activation and inflammatory responses.
• Pharmacological modulation of Hv1 offers a potential strategy for managing neuroinflammatory diseases.
• Hv1 inhibition is neuroprotective, whereas Hv1 activation is neurotoxic in the context of neuroinflammation.