Altered gut microbial profile is associated with differentially expressed fecal microRNAs in patients with functional constipationOriginal 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 study explored the link between gut microbiota and fecal microRNAs in functional constipation, a connection not previously mapped. Researchers combined 16S rRNA gene sequencing with small RNA sequencing on stool. They identified differentially abundant bacteria and differentially expressed microRNAs, then ran correlation and co-occurrence network analyses between them. A random forest model tested the combined diagnostic value of these markers. Pathway analysis predicted the biological functions of the correlated microbes and microRNAs.
Who was studied?
The cohort was 30 patients with functional constipation and 30 matched healthy controls, recruited at a hospital in Chengdu, China, from February to December 2022. Both groups were mostly women, with median age around 30 years. Patients met Rome IV criteria, with two or fewer complete spontaneous bowel movements per week for over three months. Groups matched on age, sex, and body mass index. Constipation patients had lower stool frequency and Bristol scores and worse quality of life. MicroRNA sequencing used a stratified subset of six patients and six controls.
What were the most important findings?
Constipation patients showed higher gut alpha diversity across six indices and a distinct community. Oscillibacter, Escherichia-Shigella, and other genera rose, while Lachnospiraceae members fell. LEfSe flagged 29 differing microbes. Sequencing found 44 differentially expressed fecal microRNAs, 20 up and 24 down. A network tied 11 microRNAs to nine bacterial genera. A seven-marker panel, including Oscillibacter, Escherichia-Shigella, and miR-205-5p, predicted constipation with an AUC of 0.832 (95% CI 65.73 to 98.88). Correlated microRNAs were enriched in axon guidance and glycan biosynthesis pathways.
What are the greatest implications of this study?
The work offers the first systems-level map linking fecal microRNAs and gut microbes in functional constipation, suggesting microRNAs may help mediate host-microbe crosstalk. Enrichment of axon guidance and glycan pathways hints at a mechanism affecting gut motility. The combined marker panel is a promising, noninvasive diagnostic direction from stool alone. The sample was small, especially the 12-subject microRNA subset, and the study is correlational. The authors stress that causal links between specific microRNAs and bacteria still need experimental validation.