Rett Syndrome: A Focus on Gut Microbiota

Abstract

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder affecting 1 in 10,000 live female births. Changes in microbiota composition, as observed in other neurological disorders such as autism spectrum disorders, may account for several symptoms typically associated with RTT. We studied the relationship between disease phenotypes and microbiome by analyzing diet, gut microbiota, and short-chain fatty acid (SCFA) production. We enrolled eight RTT patients and 10 age- and sex-matched healthy women, all without dietary restrictions. The microbiota was characterized by 16S rRNA gene sequencing, and SCFAs concentration was determined by gas chromatographic analysis. The RTT microbiota showed a lower α diversity, an enrichment in Bacteroidaceae, Clostridium spp., and Sutterella spp., and a slight depletion in Ruminococcaceae. Fecal SCFA concentrations were similar, but RTT samples showed slightly higher concentrations of butyrate and propionate, and significant higher levels in branched-chain fatty acids. Daily caloric intake was similar in the two groups, but macronutrient analysis showed a higher protein content in RTT diets. Microbial function prediction suggested in RTT subjects an increased number of microbial genes encoding for propionate and butyrate, and amino acid metabolism. A full understanding of these critical features could offer new, specific strategies for managing RTT-associated symptoms, such as dietary intervention or pre/probiotic supplementation.

Drosophila Histone Demethylase KDM5 Regulates Social Behavior through Immune Control and Gut Microbiota Maintenance

“…Increasing evidence suggests that the gut microbiota can affect the symptoms of intellectual disability (ID) and autism spectrum disorder (ASD) diseases (Borghi et al, 2017;Caracciolo et al, 2014;Mayer et al, 2014). It is clear that host genes influence the composition of gut microbiota (Wang et al, 2016;Snijders et al, 2016), but the molecular mechanisms that regulate hostcommensal microbiota homeostasis in normal and disease states remain largely unknown.…”

Antenatal microbial colonisation of mammalian gut

“…Sequencing reads were processed, filtered and analysed following similar procedures described in Borghi et al [48]. Briefly, read pairs were merged together by PandaSeq software [49] discarding fragments of length <300 bases or >900 bases, as well as non-overlapping sequences.…”

Akkermansia Muciniphila and Environmental Enrichment Reverse Cognitive Impairment Associated With High-fat High-cholesterol Consumption Through the Gut-brain Axis

“…In this regard, some microorganisms, such as bacteroides or Clostridia members, are able to produce BCFAs from the proteolytic metabolism of branched-chain amino acids. The higher levels of Bacteroidaceae or Peptostreptococcaceae observed in the HFHC group could be related to the higher levels of BCFAs observed, as found in other diseases related to the gut-brain axis, such as obesity [65], Rett syndrome [66], or anorexia nervosa [67]. On the other hand, there is evidence in mice that acetate can alter the levels of glutamate, glutamine, and GABA [68], and some studies have shown that SCFAs and their metabolites can stimulate vagus nerve signaling [69,70].…”