New insights into BDNF function in depression and anxiety.

Area of Science:

• Neuroscience
• Molecular Biology
• Psychiatry

Background:

• The 'neurotrophin hypothesis of depression' links stress and antidepressant treatment to brain-derived neurotrophic factor (BDNF) levels.
• Genetic studies show BDNF pathway disruption affects antidepressant efficacy but not depression onset.

Purpose of the Study:

• To explore the complex role of BDNF in mood disorders.
• To investigate the differential functions of proBDNF and mature BDNF (mBDNF).

Main Methods:

• Review of existing literature on BDNF cell biology, genetics, and mood disorders.
• Analysis of BDNF signaling pathways and its receptor, TrkB.
• Consideration of proBDNF processing and its impact on neuronal function.

Main Results:

• BDNF appears to be a target for antidepressants, not the sole mediator of depression or anxiety.
• Advances in understanding BDNF transcription, trafficking, and secretion offer new insights.
• ProBDNF and mBDNF exert opposing cellular effects, influencing mood regulation.

Conclusions:

• BDNF's role in depression is complex, involving differential actions of its precursor and mature forms.
• Understanding BDNF cell biology is crucial for novel therapeutic strategies for mood disorders.
• Opposing effects of proBDNF and mBDNF on synaptic plasticity may explain their dichotomous impact on stress and reward systems.