Published online Mar 7, 2025. doi: 10.3748/wjg.v31.i9.102256
Revised: December 6, 2024
Accepted: January 2, 2025
Published online: March 7, 2025
Processing time: 127 Days and 23.4 Hours
Runchangningshen paste (RCNSP) is a paste made of four medicinal and edible homologous Chinese medicine mixed with honey. It is known for its ability to nourish yin and blood as well as to loosen the bowel to relieve constipation. The pathophysiology of functional constipation (FC) is associated with a reduction in mucin-2 (MUC2) secretion and microbial dysbiosis.
To investigate the underlying mechanism of RCNSP against FC through MUC2 and the gut mucosal microbiota.
Ultra-performance liquid chromatography tandem mass spectrometry characterized RCNSP composition to elucidate the material basis of action. FC model was induced via loperamide gavage (16 mg/kg) twice daily for 7 days. Applying defecation function and gastrointestinal motility to assess constipation severity. Hematoxylin and eosin and Alcian blue-periodic acid-schiff staining analyzed colonic mucosal morphology. Transmission electron microscope was used to observe the ultrastructure of goblet cells (GCs). Immunofluorescence colocalization, quantitative PCR, and western blot assessed the impact of RCNSP on gene and protein expression within the NLRP6/autophagy pathway. 16S rDNA was employed to sequence the gut mucosal microbiota.
RCNSP contained 12 components with potential laxative effects. It enhanced defecation function, accelerated gastrointestinal motility, and maintained colonic mucosal integrity. RCNSP treatment significantly increased GC abundance and MUC2 production while preserving GC ultrastructure. At the molecular level, RCNSP enhanced the colocalized expression of key regulatory proteins and modulated mRNA and protein expressions in the NLRP6/autophagy pathway. Through 16S rDNA sequencing analysis, RCNSP significantly altered the mucosal microbiota composition. Specifically, it increased beneficial bacterial strains while reducing harmful ones. Simultaneously, RCNSP reduced butyrate-producing bacteria like Proteobacteria, Enterobacteriaceae, Blautia, and Eubacterium and decreased hydrogen sulfide-producing species, such as Prevotellaceae. It also reduced bile acid-inhibiting species, such as g_Eubacter_coprostanoligenes_group and Erysipelotrichaceae while increasing bile acid-producing species, such as Colidextribacter.
Our findings suggested that RCNSP ameliorated constipation through a dual mechanism: It stimulated colonic MUC2 secretion by activating NLRP6 inflammasome-mediated autophagy and modulated the composition of the mucosal microbiota.
Core Tip: Runchangningshen paste (RCNSP) is used to treat functional constipation. Based on the ultra-performance liquid chromatography tandem mass spectrometry, animal experiments, and the gut microbiota sequencing, we found that RCNSP could activate the inflammasome-mediated autophagy pathway to promote mucin-2 secretion and modulate the mucosal microbiota. In addition, mucosal microbiota might also promote mucin-2 secretion by activating the NLRP6-mediated autophagy pathway. These findings offer valuable information on the therapeutic efficacy of RCNSP and enhance the theoretical basis of traditional Chinese medicine regarding the nourishment of yin and blood for treating functional constipation.