Numerous avenues of inquiry suggest a relationship between immune dysfunction and psychiatric disorders, including schizophrenia, autism spectrum disorders, and depression. There is robust evidence for increased circulating concentrations of proinflammatory cytokines before the onset of illness.
Patients with mental disorders show a range of differences in structural brain measures compared with healthy controls, but the cause of these differences remains uncertain. Interleukin 6 (IL-6) and its receptor IL-6R could be of particular interest as it is able to cross the blood-brain barrier and increase its permeability, drawing in further local inflammatory actors,11 and may be related to treatment resistance and poor functional outcome.
In a recently published study, researchers have found a potential link between this inflammation and the structure of specific brain regions. The study appears in the journal JAMA Psychiatry.
Study Results
For the study the researchers from the University of Birmingham hypothesized that genetically predicted increased IL-6 and IL-6R activity would be associated with reduced gray matter volume and cortical thickness (CT) in areas highly relevant to neuropsychiatric disorders, including schizophrenia, autism spectrum disorder, and depression.
The study included 20,688 participants from the UK Biobank sample, which includes clinical, genomic, and neuroimaging data, and 6 postmortem brains from neurotypical individuals in the Allen Human Brain Atlas (AHBA).
They were able to show strong links between IL-6 and brain structure particularly in the temporal and frontal regions. Further analysis using the Allen Human Brain Atlas, showed that genes overexpressed in these areas are associated with conditions such as epilepsy, cognitive dysfunction, and schizophrenia.
The researchers believe that with this information, new treatment options could be developed, targeting IL-6, and that it could be the first new target for severe mental illness including schizophrenia identified in more than 60 years.
Sources:
Emily Henderson, B.Sc. (2022, Mar 30). Researchers discover potential link between inflammation and structure of specific brain regions. News Medical & Life Sciences. Retrieved from:
Image from:
Photo by Robina Weermeijer on Unsplash