Altered gut microbe metabolites in patients with AONFH: an integrated omics analysis

Background Alcohol-induced osteonecrosis of the femoral head (AONFH) is caused by excessive alcohol consumption. The gut microbiota (GM) participates in regulating host health, and its composition can be altered by alcohol. The aim of this study was to improve our understanding of the GM and its metabolites in patients with AONFH. Methods The GM of AONFH patients and normal controls (NCs) was characterized by analyzing fecal samples using 16S rDNA and metabolomic sequencing via liquid chromatography-mass spectrometry. To identify whether GM changes at the species level are associated with gut bacteria genes or functions in AONFH patients, metagenomic sequencing of fecal samples was performed. Results The abundance of 58 genera differed between the NC group and the AONFH group. Klebsiella, Holdemanella, Citrobacter, and Lentilactobacillus were significantly more abundant in the AONFH group than in the NC group. Metagenomic sequencing indicated that most of the species that exhibited significantly different abundance in AONFH subjects belonged to the genus Pseudomonas. Fecal metabolomic analysis identified several metabolites that were present at significantly different concentrations in the AONFH group and the NC group; these metabolites were involved in vitamin B6 metabolism, retinol metabolism, pentose and glucuronate interconversions, and glycerophospholipid metabolism. Furthermore, we found that these differences in metabolite levels were associated with altered abundances of specific bacterial species. Conclusions Our study provides a comprehensive landscape of the GM and metabolites in AONFH patients and substantial evidence for interplay between the gut microbiome and metabolome in AONFH pathogenesis.