Triggering neurotrophic factor actions through adenosine A2A receptor activation: implications for neuroprotection

Area of Science:

• Neuroscience
• Molecular Biology
• Pharmacology

Background:

• G protein-coupled receptors (GPCRs) and tropomyosin-related kinase (Trk) receptors possess distinct structures and signaling mechanisms.
• Cross-talk between these receptor families was initially unexpected.
• Accumulating evidence suggests a critical role for adenosine A2A receptor activity in mediating neurotrophic factor functions.

Purpose of the Study:

• To review and discuss the evidence for tonic adenosine A2A receptor activity enabling neurotrophic factor actions.
• To explore the implications of this cross-talk in synaptic transmission, plasticity, and neuroprotection.
• To consider therapeutic strategies for neurodegenerative diseases based on these findings.

Main Methods:

• Literature review and synthesis of existing research.
• Analysis of experimental data on receptor interactions and signaling pathways.
• Discussion of the physiological and pathological relevance of adenosine A2A receptor modulation.

Main Results:

• Tonic adenosine A2A receptor activity is essential for synaptic actions of neurotrophic factors, including brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF).
• Enhanced A2A receptor activity in aging may compensate for TrkB receptor loss, potentially preserving BDNF's facilitatory effects and offering neuroprotection.
• A2A receptors facilitate neurotrophic factor signaling at both pre- and post-synaptic levels, influencing synaptic transmission and plasticity.

Conclusions:

• Tonic adenosine A2A receptor activity is a fundamental requirement for neurotrophic factor-mediated neuronal functions.
• This receptor cross-talk presents potential therapeutic targets for mitigating age-related neurodegeneration.
• Understanding these mechanisms is vital for developing novel strategies against neurodegenerative diseases.