The kynurenine pathway: a finger in every pie

Area of Science:

• Neuroscience
• Immunology
• Biochemistry

Background:

• The kynurenine pathway (KP) generates nicotinamide adenine dinucleotide (NAD+), essential for cellular energy.
• KP activity increases during immune responses, highlighting its role in immune regulation.
• Kynurenines are neuroactive, influencing neuroplasticity and NMDA receptor signaling.

Purpose of the Study:

• To review the mechanistic pathways linking kynurenines to psychiatric disorders.
• To explore the kynurenine pathway's interaction with endocrine, metabolic, and hormonal systems.
• To discuss novel therapeutic strategies targeting the kynurenine pathway.

Main Methods:

• Literature review of preclinical and clinical studies.
• Analysis of mechanistic pathways involving kynurenine metabolism.
• Synthesis of findings on kynurenine involvement in psychiatric conditions.

Main Results:

• Kynurenines are implicated in depression and schizophrenia-like cognitive deficits.
• The KP interacts with systems commonly disrupted in psychiatric disorders.
• Kynurenine metabolites show potential as biomarkers for treatment response.

Conclusions:

• The kynurenine pathway significantly impacts emotion, cognition, and metabolic function, influencing psychiatric disorder risk.
• Therapeutic interventions targeting the KP offer novel treatment possibilities.
• Alterations in kynurenine metabolism by therapies like ECT and ketamine suggest biomarker utility.