Baohe pill decoction treats diarrhea induced by high-fat and high-protein diet by regulating lactase-producing bacteria in intestinal mucosa

Gut microbiota dysbiosis and intestinal barrier impairment in diarrhea caused by cold drink and high-fat diet

Cold drink and high-fat diet (CDHFD) are common diet patterns. However, the potential risks remain unclear. We investigated the effects of CDHFD in adult mice and explored the mechanisms of action. Twenty adult male mice were randomly divided into control and model groups, and the control group was fed a normal diet, whereas the model group was fed CDHFD for 28 days. We found that mice in the model group developed diarrhea symptoms accompanied by fatigue and weakness. Analysis of the intestinal flora revealed that the model group had a lower diversity and richness of microorganism species in the gut than the control group. Furthermore, the characteristic analysis indicated that CDHFD downregulated specific bacteria, such as norank_f_Muribaculaceae, Muribaculum, and Odoribacter, which are known to be associated with the systemic inflammatory response and mucosal barrier function. Blood tests showed that immune cells and inflammatory cytokines were significantly elevated in the model group, along with increased LPS induced by CDHFD. Pathological investigations demonstrated that CDHFD damages the intestinal mucosa while affecting the expression of tight junction proteins, including ZO-1, Claudin-1, Claudin-2, and Occludin, which may be attributed to the activation of the TRAF6/IκB/p65 signaling pathway. In conclusion, impaired gut microbial and mechanical barrier function is responsible for CDHFD-induced diarrhea. In this study, we constructed a model of diet-induced diarrhea by simulating human dietary patterns, evaluated the long-term effects of CDHFD on human intestinal barriers and immune systems, and revealed its mechanism of action based on chronic inflammation. This study validated the model's fit to provide an effective screening model for drug or functional food development.

The dysfunction in intestinal microorganisms and enzyme activity as significant contributors to diarrhea with kidney-yang deficiency syndrome

Object

To investigate the pathogenesis of diarrhea with kidney-yang deficiency syndrome by examining characteristic changes in intestinal microorganisms, enzyme activities, oxidative stress, and metabolism indices.

Methods

Twenty mice were randomly and equally divided into control group (NC) and model group (NM). Mice in NM group received adenine suspension at a dosage of 50 mg/(kg⋅day) by gavage, 0.4 mL/time, once a day for 14 days, and Folium sennae decoction at a dosage of 10 g/(kg⋅day) by gavage, 0.4 mL/time, once a day for 7 days, starting on 8th day. Mice in NC group were administered an equivalent amount of sterile water by gavage once a day for 7 days, and twice a day from the 8th day. After modeling, assessments encompassed microbial culture, organ index calculation, microbial and enzyme activity detection, malondialdehyde (MDA) content determination, superoxide dismutase (SOD) activity, blood biochemical tests, and observation of kidney tissue pathological changes.

Results

The results showed that in NM group, a reduction in the number of Lactobacillus and Bifidobacteria was noted, accompanied by an increase in the number of bacteria and E. coli. Xylanase activity in the intestinal contents and mucosa, protease activity in the intestinal mucosa, and intestinal mucosa microbial activity were diminished. Conversely, the activities of amylase, sucrase, and lactase increased in intestinal mucosa. Additionally, there was an elevation in the level of MDA. Renal tubular dilatation and inflammatory cell infiltration were observed in the renal interstitium.

Conclusion

These dysfunctions in intestinal microorganisms and enzyme activities suggest potential involvement in diarrhea with kidney-yang deficiency syndrome.

Gut microbiome and plasma metabolome alterations in myopic mice

Background

Myopia is one of the most common eye diseases leading to blurred distance vision. Inflammatory diseases could trigger or exacerbate myopic changes. Although gut microbiota bacteria are associated with various inflammatory diseases, little is known about its role in myopia.

Materials and methods

The mice were randomly divided into control and model groups, with the model group being attached-30D lens onto the eyes for 3 weeks. Then, mouse cecal contents and plasma were collected to analyze their intestinal microbiota and plasma metabolome.

Results

We identified that the microbial composition differed considerably between the myopic and non-myopic mice, with the relative abundance of Firmicutes phylum decreased obviously while that of Actinobacteria phylum was increased in myopia. Furthermore, Actinobacteria and Bifidobacterium were positively correlated with axial lengths (ALs) of eyeballs while negatively correlated with refractive diopters. Untargeted metabolomic analysis identified 141 differentially expressed metabolites, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed considerable enrichment mainly in amino acid metabolism pathways. Notably, pathways involved glutamate metabolism including "Glutamine and D-glutamate metabolism" and "Alanine, aspartate and glutamate metabolism" was changed dramatically, which presented as the concentrations of L-Glutamate and L-Glutamine decreased obviously in myopia. Interestingly, microbiome dysbiosis and metabolites alternations in myopia have a disrupting gut barrier feature. We further demonstrated that the gut barrier function was impaired in myopic mice manifesting in decreased expression of Occludin, ZO-1 and increased permeation of FITC-dextran.

Discussion

Myopic mice had obviously altered gut microbiome and metabolites profiles compared to non-myopic mice. The dysbiosis and plasma metabolomics shift in myopia had an interrupting gut barrier feature. Our study provides new insights into the possible role of the gut microbiota in myopia and reinforces the potential feasibility of microbiome-based therapies in myopia.