GPR68 (OGR1) Modulators for Neurodegeneration

GPR68 (OGR1) Modulators for Neurodegeneration

Introduction

<table class="infobox infobox-therapeutic">
<tr>
<th class="infobox-header" colspan="2">GPR68 (OGR1) Modulators for Neurodegeneration</th>
</tr>
<tr>
<td class="label">Approach</td>
<td>Development Stage</td>
</tr>
<tr>
<td class="label">Small molecule agonists</td>
<td>Preclinical</td>
</tr>
<tr>
<td class="label">Positive allosteric modulators</td>
<td>Discovery</td>
</tr>
<tr>
<td class="label">pH-modulating therapies</td>
<td>Adjunct approach</td>
</tr>
<tr>
<td class="label">Target</td>
<td>GPR68 (OGR1, GPR68)</td>
</tr>
<tr>
<td class="label">Drug Class</td>
<td>Proton-sensing GPCR modulator</td>
</tr>
<tr>
<td class="label">Endogenous Activator</td>
<td>Protons (H⁺)</td>
</tr>
<tr>
<td class="label">Signaling</td>
<td>Gq-coupled</td>
</tr>
</table>

GPR68, also known as OGR1 (Ovarian Cancer G-Protein Coupled Receptor 1), is a proton-sensing G-protein coupled receptor that plays important roles in cellular pH homeostasis and stress responses. As a pH sensor in the brain, GPR68 is activated by extracellular acidosis that occurs during neuroinflammation, ischemia, and neurodegeneration, making it a potential therapeutic target for neurodegenerative diseases. [@lp2018]

GPR68 Biology

GPR68 is encoded by the [GPR68](/genes/gpr68) gene and belongs to the proton-sensing GPCR family (including GPR4, GPR65, GPR132). Key features include:

GPR68 (OGR1) Modulators for Neurodegeneration

Introduction

<table class="infobox infobox-therapeutic">
<tr>
<th class="infobox-header" colspan="2">GPR68 (OGR1) Modulators for Neurodegeneration</th>
</tr>
<tr>
<td class="label">Approach</td>
<td>Development Stage</td>
</tr>
<tr>
<td class="label">Small molecule agonists</td>
<td>Preclinical</td>
</tr>
<tr>
<td class="label">Positive allosteric modulators</td>
<td>Discovery</td>
</tr>
<tr>
<td class="label">pH-modulating therapies</td>
<td>Adjunct approach</td>
</tr>
<tr>
<td class="label">Target</td>
<td>GPR68 (OGR1, GPR68)</td>
</tr>
<tr>
<td class="label">Drug Class</td>
<td>Proton-sensing GPCR modulator</td>
</tr>
<tr>
<td class="label">Endogenous Activator</td>
<td>Protons (H⁺)</td>
</tr>
<tr>
<td class="label">Signaling</td>
<td>Gq-coupled</td>
</tr>
</table>

GPR68, also known as OGR1 (Ovarian Cancer G-Protein Coupled Receptor 1), is a proton-sensing G-protein coupled receptor that plays important roles in cellular pH homeostasis and stress responses. As a pH sensor in the brain, GPR68 is activated by extracellular acidosis that occurs during neuroinflammation, ischemia, and neurodegeneration, making it a potential therapeutic target for neurodegenerative diseases. [@lp2018]

GPR68 Biology

GPR68 is encoded by the [GPR68](/genes/gpr68) gene and belongs to the proton-sensing GPCR family (including GPR4, GPR65, GPR132). Key features include:

• pH-Sensitive: Activated by extracellular acidosis (optimal pH ~6.5)
• Gq-coupled: Activates phospholipase C, increases IP3/DAG
• Brain Expression: Neurons, astrocytes, microglia, endothelial cells
• Tissue Distribution: Highest in brain, also in bone, kidney, heart

Mechanism of Action

GPR68 modulators work through acid-sensing and pro-survival signaling:

Key Mechanisms

Therapeutic Potential

Alzheimer's Disease

GPR68 modulators may benefit AD through:

• Protection against acidic microenvironments
• Support of neuronal survival during inflammation
• Potential modulation of amyloid processing
• Enhanced cellular stress responses

Parkinson's Disease

GPR68 is relevant for PD:

• Acidic environments in substantia nigra during degeneration
• Protection of dopaminergic neurons
• Modulation of microglial responses
• Support of cellular metabolism

Other Applications

• Stroke and cerebral ischemia [@ch2021]
• Traumatic brain injury
• [Multiple Sclerosis](/diseases/multiple-sclerosis)
• [Amyotrophic Lateral Sclerosis](/diseases/amyotrophic-lateral-sclerosis)

Drug Development

GPR68 remains an early-stage target. Approaches include:

Drug Properties

Research Status

GPR68 is an emerging target with key challenges:

• Developing selective brain-penetrant compounds
• Understanding tissue-specific effects
• Context-dependent signaling outcomes
• Limited knowledge of synthetic ligands

References

Related Pages

• [Proton-Sensing GPCRs](/therapeutics/gpr65-modulators-neurodegeneration)
• [Acid-Sensing Ion Channels](/therapeutics/amiloride)
• [Neuroprotection](/therapeutics/neuroprotection)
• [GPR68 Gene](/genes/gpr68)