Li H, Liu T, Heinsberg LW, Lockwood MB, Wainwright DA, Jang MK, Doorenbos AZ. Systematic Review of the Kynurenine Pathway and Psychoneurological Symptoms Among Adult Cancer Survivors.
Biol Res Nurs 2020;
22:472-484. [PMID:
32602357 PMCID:
PMC7708728 DOI:
10.1177/1099800420938141]
[Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The co-occurrence of multiple psychoneurological symptoms, including pain, sleep disturbance, fatigue, depression, anxiety, and cognitive disturbance among adult cancer survivors led us to question which common biological mechanisms are shared among these conditions. Variances in tryptophan (Trp) levels and downstream metabolites of the kynurenine (Kyn) metabolic pathway are known to affect immune response and psychoneurological symptoms. The objective of this systematic review was to help us (a) better understand the role of the Kyn pathway in psychoneurological symptoms among adult cancer survivors and (b) identify common significant biomarkers across psychoneurological symptoms as a guide for future research. Some evidence has shown that decreased Trp levels and increased Kyn, Trp/Kyn ratio, and kynurenic acid/Trp ratio in parallel with immune activation are correlated with some psychoneurological symptoms among people undergoing cancer treatment, although discrepancies exist between studies. Kyn pathway activation could also be associated with psychoneurological symptoms among adult cancer survivors, but further research is needed to confirm its exact etiological role with respect to psychoneurological symptoms.
Collapse