TRPM2 enhances ischemic excitotoxicity by associating with PKCγ

Area of Science:

• Neuroscience
• Molecular Biology
• Pharmacology

Background:

• N-methyl-D-aspartate receptor (NMDAR)-mediated excitotoxicity is a key factor in ischemic neuronal death.
• Previous attempts to target NMDARs for brain injury mitigation have failed in clinical trials.

Purpose of the Study:

• To discover a novel therapeutic strategy for NMDAR-mediated excitotoxicity in ischemic stroke.
• To investigate the interaction between transient receptor potential melastatin 2 (TRPM2) and protein kinase Cγ (PKCγ) and its role in NMDAR potentiation.

Main Methods:

• Identification of the TRPM2-PKCγ interaction motif (M2PBM).
• Development of an interfering peptide (TAT-M2PBM) to disrupt the TRPM2-PKCγ association.
• Assessment of the peptide's efficacy in attenuating NMDAR-mediated excitotoxicity and ischemic brain injury.

Main Results:

• The TRPM2-PKCγ interaction facilitates Ca2+ influx, activating PKCγ and enhancing extrasynaptic NMDAR (esNMDAR) activity.
• Disruption of the TRPM2-PKCγ interaction using TAT-M2PBM reduced excitotoxic neuronal death.
• TRPM2-PKCγ uncoupling attenuated ischemic brain injury without compromising PKCγ function.

Conclusions:

• TRPM2-PKCγ uncoupling represents a promising therapeutic approach for ischemic stroke.
• Targeting the TRPM2-PKCγ interaction offers a novel strategy to mitigate NMDAR-mediated excitotoxicity.
• The findings provide a basis for developing new treatments for stroke-related brain damage.