Cross-sectional evaluation of gut microbial-host cometabolites in patients with chronic pancreatitis

Gut bacteria facilitate nutrient metabolism and generate small molecules that form part of the broader "metabolome". It is unclear whether these metabolites are disturbed in chronic pancreatitis (CP). This study aimed to evaluate the gut microbial-host cometabolites and their relationship in patients with CP.

Fecal samples were collected from 40 patients with CP and 38 healthy family members. Each sample was examined with 16S rRNA gene profiling and gas chromatography time-of-flight mass spectrometry to estimate the relative abundances of specific bacterial taxa between the two groups and to profile any changes in the metabolome, respectively. Correlation analysis was used to evaluate the differences in metabolites and gut microbiota between the two groups.

The abundance of Actinobacteria was lower at the phylum level, and that of Bifidobacterium was lower at the genus level in the CP group. Eighteen metabolites had significantly different abundances and the concentrations of 13 metabolites were significantly different between the two groups. Oxoadipic acid and citric acid levels were positively correlated with Bifidobacterium abundance (r = 0.306 and 0.330, respectively, both P < 0.05), while the 3-methylindole concentration was negatively correlated with Bifidobacterium abundance (r = -0.252, P = 0.026) in CP.

Gut microbiome and host microbiome metabolic products might be altered in patients with CP. Evaluating gastrointestinal metabolite levels may further enhance our understanding of the pathogenesis and/or progression of CP.