NMN Maintains Intestinal Homeostasis by Regulating the Gut Microbiota
Pan Huang et al. · Frontiers in Nutrition · 2021
Evidence type: Preclinical mechanistic studyInterpretive weight: Mechanistic contextResearch area: Gut microbiome and intestinal barrier
DesignPreclinical long-term mouse feeding study with 16S rDNA microbiome profiling, fecal metabolomics and intestinal-barrier assays
PopulationC57BL/6J mice
SampleMultiple dietary NMN groups; see publication for group sizes
InterventionDifferent concentrations of NMN administered long term in drinking water/feed regimen
EndpointsGut microbiota diversity and composition; Fecal metabolites and bile acids; Goblet cells and mucus thickness; Tight-junction proteins; Intestinal mucosal permeability
What the publication reported
This mouse study examined whether long-term NMN changes the gut microbiome and intestinal barrier.
NMN altered the abundance of multiple bacterial groups and fecal bile-acid-related metabolites. The treated mice also showed changes in goblet cells, mucus thickness, tight-junction proteins and intestinal permeability.
Microbiome findings are highly context dependent, and mouse gut ecology differs from humans. The study therefore provides mechanistic context rather than evidence that NMN improves human gut health.
Key findings
NMN altered gut microbial composition in the treated mice.
Several butyrate-associated and other bacterial taxa increased while some taxa decreased.
Fecal bile-acid-related metabolites changed.
Intestinal mucus and tight-junction measures were altered in a direction interpreted as improved barrier function.
What it cannot establish
Mouse study only.
Microbiome composition is strongly affected by housing, diet and laboratory conditions.
Changes in bacterial abundance do not automatically imply a health benefit.
No human gastrointestinal outcomes were tested.
HealthspanX claim boundary: This study does not establish that NMN improves the human microbiome, digestion, intestinal permeability or gastrointestinal health.
