Macroeconomics

Amino acid

Neuroscience

Biology

Depression (economics)

Animal models of depression

Kynurenine

Receptor

Psychiatry

Kynurenine pathway

Economics

Biochemistry

Dopamine

Antidepressant

Drug

Indoleamine 2,3-dioxygenase

Immunology

Psychology

Hippocampus

Drug development

Inflammation

Glutamate receptor

Tryptophan

Internal medicine

Pharmacology

Mood

Medicine

Glutamatergic

Anhedonia

The International Journal of Neuropsychopharmacology

Inflammation and depression are closely inter-related; inflammation induces symptoms of depression and, conversely, depressed mood and stress favor an inflammatory phenotype. The mechanisms that mediate the ability of inflammation to induce symptoms of depression are intensively studied at the preclinical level. This review discusses how it has been possible to build animal models of inflammation-induced depression based on clinical data and to explore critical mechanisms downstream of inflammation. Namely, we focus on the ability of inflammation to increase the activity of the tryptophan-degrading enzyme, indoleamine 2,3 dioxygenase, which leads to the production of kynurenine and downstream neuroactive metabolites. By acting on glutamatergic neurotransmission, these neuroactive metabolites play a key role in the development of depression-like behaviors. An important outcome of the preclinical research on inflammation-induced depression is the identification of potential novel targets for antidepressant treatments, which include targeting the kynurenine system and production of downstream metabolites, altering transport of kynurenine into the brain, and modulating glutamatergic transmission.

Inflammation Models of Depression in Rodents: Relevance to Psychotropic Drug Discovery