Trial reportMolecular psychiatry2005
IDO and interferon-alpha-induced depressive symptoms: a shift in hypothesis from tryptophan depletion to neurotoxicity.
Trial report in Molecular psychiatry, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 202 papers, 5 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
202 citing papers in PubMed, 5 syntheses or guidelines pooled it, 440 citations in OpenAlex.
- Effect of immune activation on the kynurenine pathway and depression symptoms - A systematic review and meta-analysis.Neuroscience and biobehavioral reviews · 2020Pooled it
- Effects of inflammation on the kynurenine pathway in schizophrenia - a systematic review.Journal of neuroinflammation · 2020Pooled it
- Pathogenetic and Therapeutic Applications of Tumor Necrosis Factor-α (TNF-α) in Major Depressive Disorder: A Systematic Review.International journal of molecular sciences · 2016Pooled it
- Ketamine as a potential treatment for suicidal ideation: a systematic review of the literature.Drugs in R&D · 2015Pooled it
- Side effects of interferon-alpha therapy.Pharmacy world & science : PWS · 2005Pooled it
- Trial
- Acute administration of ibuprofen increases serum concentration of the neuroprotective kynurenine pathway metabolite, kynurenic acid: a pilot randomized, placebo-controlled, crossover study.Psychopharmacology · 2022Trial
- [Interferon α therapy in patients with chronic hepatitis C infection: biopsychosocial consequences].Der Nervenarzt · 2012Trial
- No increase in depression with low-dose maintenance peginterferon in prior non-responders with chronic hepatitis C.Journal of affective disorders · 2011Trial
- Functional polymorphisms in the interleukin-6 and serotonin transporter genes, and depression and fatigue induced by interferon-alpha and ribavirin treatment.Molecular psychiatry · 2009Trial
- Pathogenesis and therapeutic strategies for neuropsychiatric lupus centered on innate immune activation.Human cell · 2026Review
- Environmental and genetic risk factors of depression converge on neuronal dysfunction driven by changes in cholesterol homeostasis.Developmental cell · 2026Article
- Burden of psychiatric disease inversely correlates with Alzheimer's age at onset.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2025Article
- Plasma and Visceral Organ Kynurenine Metabolites Correlate in the Multiple Sclerosis Cuprizone Animal Model.International journal of molecular sciences · 2025Article
- Possible antidepressant mechanism of acupuncture: targeting neuroplasticity.Frontiers in neuroscience · 2025Review
- Decoding serotonin: the molecular symphony behind depression.Frontiers in cellular neuroscience · 2025Review
- Untangling Depression in Schizophrenia: The Role of Disorganized and Obsessive-Compulsive Symptoms and the Duration of Untreated Psychosis.Biomedicines · 2024Article
- Serotonin Availability Shapes the Effects of Phenelzine on Inflammatory Response and Gene Expression in Macrophages.Cureus · 2024Article
- Kynurenines and Inflammation: A Remarkable Axis for Multiple Sclerosis Treatment.Pharmaceuticals (Basel, Switzerland) · 2024Review
- Multi-omics analysis of the gut microbiome and metabolites associated with the psychoneurological symptom cluster in children with cancer receiving chemotherapy.Journal of translational medicine · 2024Article
142 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Studies show that administration of interferon (IFN)-alpha causes a significant increase in depressive symptoms. The enzyme indoleamine 2,3-dioxygenase (IDO), which converts tryptophan (TRP) into kynurenine (KYN) and which is stimulated by proinflammatory cytokines, may be implicated in the development of IFN-alpha-induced depressive symptoms, first by decreasing the TRP availability to the brain and second by the induction of the KYN pathway resulting in the production of neurotoxic metabolites. Sixteen patients with chronic hepatitis C, free of psychiatric disorders and eligible for IFN-alpha treatment, were recruited. Depressive symptoms were measured using the Montgomery Asberg Depression Rating Scale (MADRS). Measurements of TRP, amino acids competing with TRP for entrance through the blood-brain barrier, KYN and kynurenic acid (KA), a neuroprotective metabolite, were performed using high-performance liquid chromatography. All assessments were carried out at baseline and 1, 2, 4, 8, 12 and 24 weeks after treatment was initiated. The MADRS score significantly increased during IFN-alpha treatment as did the KYN/TRP ratio, reflecting IDO activity, and the KYN/KA ratio, reflecting the neurotoxic challenge. The TRP/CAA (competing amino acids) ratio, reflecting TRP availability to the brain, did not significantly change during treatment. Total MADRS score was significantly associated over time with the KYN/KA ratio, but not with the TRP/CAA ratio. Although no support was found that IDO decreases TRP availability to the brain, this study does support a role for IDO activity in the pathophysiology of IFN-alpha-induced depressive symptoms, through its induction of neurotoxic KYN metabolites.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.