Microbiota in anorexia nervosa: The triangle between bacterial species, metabolites and psychological testsOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This case-control study integrated gut microbiome data with clinical, dietary, and psychological measures in anorexia nervosa (AN). It aimed to probe the microbiota-gut-brain axis in the disorder. Fecal microbiota was profiled by 16S rRNA gene sequencing on Illumina MiSeq, with Methanobrevibacter smithii quantified by real-time PCR. Short chain fatty acids in stool and serum were measured by gas chromatography. Psychopathology was assessed with standardized questionnaires.
Who was studied?
The study enrolled 15 women with anorexia nervosa and 15 age-, sex-, and ethnicity-matched healthy controls in Milan, Italy. AN patients had restrictive behavior and a very low body mass index (under 14 kg/m2 at enrollment). Mean BMI was 13.9 in AN versus 22.1 in controls. AN subjects had lower energy, fat, and carbohydrate intake, plus higher ALT and AST. All AN participants were female adults or adolescents.
What were the most important findings?
The AN gut was significantly enriched in Enterobacteriaceae and the archaeon Methanobrevibacter smithii compared with controls. The genera Roseburia, Ruminococcus, and Clostridium were depleted. Fecal total short chain fatty acids, butyrate, and propionate were significantly lower in AN (p below 0.05). Butyrate inversely correlated with anxiety and depression scores. BMI negatively correlated with a Bacteroidetes-phylum species and with psychopathology scores. Propionate directly correlated with insulin and with Roseburia inulinivorans abundance.
What are the greatest implications of this study?
The findings support the idea that gut dysbiosis participates in the neurobiology of anorexia nervosa. Reduced butyrate-producing bacteria and their metabolites tracked with worse anxiety and depression. This hints that microbial modulation, such as probiotics or prebiotics, might complement AN treatment. Because the low-calorie content fits AN care, the authors see it as feasible. Causality was not proven, and the small 15-versus-15 sample limits the conclusions.