Wednesday, 31 October 2012

More metabolomics, amino acids, gut bacteria and autism

"Here he goes again" I hear you say as today's micro-post focuses on a rather interesting paper from Xue Ming and colleagues* which, and I quote, "detected abnormal amino acid metabolism, increased oxidative stress, and altered gut microbiomes in ASD".
Ur-inal or mine? @ Wikipedia  

The name of the game was a favourite -omics of mine, metabolomics (see this recent post for a brief overview) and in particular how the appliance of some really quite powerful science to urine specimens provided by children with autism and aysmptomatic controls, revealed some interesting differences.

A brief overview of the paper and results bearing in mind that I'm still pursuing the full-text paper:

  • Using a combination of both liquid- and gas chromatography based mass spectrometry, urine specimens were analysed for 48 children diagnosed with as autism spectrum disorder (ASD) and 53 age-matched not-autism controls.
  • Results: after some nifty statistical analysis, urinary amino acid output was one of the most important factors and in particular several amino acids presenting in lower, concentration controlled levels in the ASD group over controls. 
  • With shadows of the findings from Prof. Jeremy Nicholson a few years back (see this post), the authors conclude that "several gut bacterial metabolites were significantly altered in ASD children who had gastrointestinal dysfunction".

As indicated, this post is a preliminary one and I hope to fill in a few gaps when I get the full-text paper. Nevertheless, such work as this from Ming and colleagues is indeed important fodder for this blog. We've been here before both with autism and indeed conditions like schizophrenia too albeit not necessarily presenting with the same patterns of findings. Indeed, very much like the rising prominence of disciplines like metabolomics to conditions like schizophrenia - five serum and one urine metabolite for example - there is perhaps some important data to be derived from such studies, at least on the functional differences between autism and not-autism. That outside of the known metabolic disorders with a focus on amino acid chemistry that can present with autism or autism-like characteristics.

The gut bacteria-autism connection? Don't get me started again, as once more another study suggests some potential involvement from those trillions of bacterial masters. I haven't forgotten the old correlation does not equal causation mantra by the way, just pointing out that something seems a little bit unusual with gut bacteria in some cases of autism.

More to follow...


* Ming X. et al. Metabolic perturbance in autism spectrum disorders: a metabolomics study. J Proteome Res. October 2012.

---------- Ming X, Stein TP, Barnes V, Rhodes N, & Guo L (2012). Metabolic Perturbance in Autism Spectrum Disorders: A Metabolomics Study. Journal of proteome research PMID: 23106572