Bell JG, Sargent JR, Tocher DR, Dick JR. (2000) Prostaglandins Leukotrienes and Essential Fatty Acids 63(1-2) 21-5
The fatty acid compositions of red blood cell (RBC) phospholipids from a patient with autistic spectrum disorder (ASD) had reduced percentages of highly unsaturated fatty acids (HUFA) compared to control samples.
The percentage of HUFA in the RBC from the autistic patient was dramatically reduced (up to 70%) when the sample was stored for 6 weeks at -20 degrees C. However, only minor HUFA reductions were recorded in control samples stored similarly, or when the autistic sample was stored at -80 degrees C.
A similar instability in RBC HUFA compositions upon storage at -20 degrees C has been recorded in schizophrenic patients. In a number of other neurodevelopmental conditions, including attention deficit hyperactivity disorder (ADHD) and dyslexia, reduced concentrations of RBC HUFA have been recorded.
The extent and nature of these aberrations require further assessment to determine a possible common biochemical origin of neurodevelopmental disorders in general. To facilitate this, a large scale assessment of RBC fatty acid compositions in patients with ASD, and related disorders, should be performed as a matter of urgency.
Supplementing cells in culture with the tryptophan metabolite indole acrylic acid (IAA) affected the levels of cellular HUFA and prostaglandin production. Indole acroyl glycine (IAG), a metabolite of IAA excreted in urine, is found in high concentrations in patients with neurodevelopmental disorders including ASD, ADHD, dyslexia, Asperger's syndrome and obsessive compulsive disorder.
Dr Gordon Bell is the UK's leading expert on fatty acids in the autistic spectrum, and these are pioneering findings, on which he and his colleagues have continued to build since this paper was published. Further studies involving more subjects have supported these initial observations. As expected, they have also shown individual variability within the autistic spectrum. However, this kind of biochemical approach offers real hope of discovering some of the underlying causes of autistic behaviours, which will undoubtedly vary between individuals.
The reasons for this unusually rapid loss of HUFA in blood samples from autistic subjects are not yet known, but may include over-activity of certain enzymes and/or poor antioxidant defences. We agree with the authors that this issue requires urgent large-scale investigation.