Zengye decoction induces alterations to metabolically active gut microbiota in aged constipated ratsOriginal 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?
The study examined how Zengye decoction (ZYD), a traditional Chinese medicinal formula, affects the gut microbiota and host metabolites in aged rats with constipation. Researchers used 16S rRNA gene sequencing to characterize the fecal microbiome and then predicted the metabolic function of the altered bacterial community. They paired this with 1H NMR profiling of urine and fecal samples to verify the metabolic changes suggested by the sequencing data. The overall goal was to clarify the mechanisms by which ZYD works, since these had remained unclear despite its clinical use for constipation and skin dryness syndrome.
Who was studied?
The subjects were aged rats divided randomly into three groups of ten animals each: a control group, a recovery group, and a ZYD-treated group. An aged constipation model was established in both the recovery and ZYD groups before treatment began. Urinary and fecal samples were collected from each animal for microbiome and metabolite analysis, so no human cohort was involved; this was an animal model study.
What were the most important findings?
ZYD reduced the abundance of harmful gut bacteria, including Desulfovibrio, Ruminococcus, and Prevotella, in the aged constipated rats. Desulfovibrio is a sulfate-reducing genus capable of generating hydrogen sulfide, so its reduction points to a shift in sulfur-related metabolic activity within the gut community. These bacterial changes were accompanied by alterations in metabolically active gut microbiota and were reflected in the host metabolite profiles measured by NMR in urine and feces. The convergence of sequencing-based predictions and NMR-based metabolite verification supports a genuine link between the microbiota shift and host metabolic changes.
What are the greatest implications of this study?
The findings suggest that ZYD's therapeutic effect on constipation may work partly by remodeling the gut microbiota, including suppressing sulfate-reducing organisms like Desulfovibrio, rather than acting solely through direct host pathways. This supports a microbiota-mediated mechanism for a traditional medicinal formula that had previously lacked clear mechanistic explanation. It also suggests that gut bacteria capable of hydrogen sulfide production may be relevant targets when evaluating treatments for age-related constipation. Further work would be needed to confirm these mechanisms and their relevance to human patients.