Ricerc@Sapienza

Background and Aims. Recent evidence implicates gut microbiota
(GM) and immune alterations in autism spectrum disorders (ASD). We assess
GM profile and peripheral levels of immunological, neuronal and bacterial
molecules in ASD children and controls. Alarmin HMGB1 was explored as a
non-invasive biomarker to monitor gastrointestinal (GI) symptoms.
Methods.Thirty ASD children and 14 controls entered into the study. GM
metagenomic analysis was performed for 16 ASD patients and 7 controls. GM
functional profile was assessed by GO term analysis. Blood levels of IL-
1beta, TNFalpha, TGFbeta, IL-10, INFgamma, IL-8, lipopolysaccharide,
Neurotensin, Sortilin1 and GSSG/GSH ratio were analyzed in all subjects
by ELISA. Fecal HMGB1 was analyzed by western blot.
Results. We observed a significant decrease in bacterial diversity.
Furthermore, 82 GO terms underrepresented in ASD. Four of them pointed at
3,3 phenylpropionate catabolism and were imputable to Escherichia coli
group. Serum levels of TNFalpha, TGFbeta, NT and SORT-1 increased in ASD
patients. Fecal levels of HMGB1 correlated with GI signs severity in ASD
children.
Conclusions. We suggest that a decrease of E. coli might affect the
propionate catabolism in ASD. We report occurrence of peripheral
inflammation in ASD children. We propose fecal HMGB1 as non-invasive
biomarker to detect GI symptoms.