An Imbalance in Tryptophan Breakdown Products Linked to Poor Cognitive Performance in Lupus
Breakdown of tryptophan by interferon-alpha in lupus may lead to an imbalance in substances that can negatively affect the brain. Updated molecular research by Lupus Foundation of America Gary S. Gilkeson Career Development Awardee Erik Anderson, MD, PhD, affirms an association between an imbalance of these two substances in the blood, quinolinic acid and kynurenic acid, and poor cognitive performance in people with lupus.
In the study, 74 people with lupus and 74 healthy volunteers underwent cognitive testing and had blood levels of tryptophan breakdown products measured: kynurenine, quinolinic acid, and kynurenic acid. Those with lupus performed worse than healthy volunteers on the majority of cognitive tests. Elevated quinolinic acid relative to kynurenic acid was associated with poor performance on a test of working memory and visuospatial processing in lupus. This association remained significant when controlling for many other characteristics that could potentially affect cognitive performance, such as lupus disease activity and medications.
“Cognitive dysfunction, such as memory difficulties, commonly affects lupus patients, and yet is often difficult to attribute to lupus. Further, therapies are lacking. We report a novel association between an imbalance in quinolinic acid relative to kynurenic acid and poor cognitive test performance in lupus. More work needs to be done to further understand this association, but if confirmed, may lead to a marker for cognitive dysfunction in lupus or a target for therapy,” said Dr. Anderson, lead study author and Gary S. Gilkeson Career Development Awardee with the Lupus Foundation of America.
Learn more about Dr. Anderson and his research efforts.