Emodin modulates gut microbial community and triggers intestinal immunity.

BACKGROUND: The gut microbiota (GM) plays an important role in human health and is being investigated as a possible target for new therapies. Although there are many studies showing that emodin can improve host health, emodin-GM studies are scarce. Here, the effects of emodin on the GM were investigated in vitro and in vivo. RESULTS: In vitro single bacteria cultivation showed that emodin stimulated the growth of beneficial bacteria Akkermansia, Clostridium, Roseburia, and Ruminococcus but inhibited major gut enterotypes (Bacteroides and Prevotella). Microbial community analysis from a synthetic gut microbiome model through co-culture indicated the consistent GM change by emodin. Interestingly, emodin stimulated Clostridium and Ruminococcus (which are related to Roseburia and Faecalibacterium) in a mice experiment and induced anti-inflammatory immune cells, which may correlate with its impact on specific gut bacteria. CONCLUSION: Emodin (i) showed similar GM changes in monoculture, co-culture, and in an in vivo mice experiment and (ii) simulated regulatory T-cell immune responses in vivo. This suggest that emodin may be used to modulate the GM and improve health. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Simulation of the mucosal environment in the re-construction of the synthetic gut microbial ecosystem.

Human gut surface-attached mucosal microbiota plays significant roles in human health and diseases. This study sought to simulate the mucosal environment using mucin-agar gel and synthetic mucosal microbial community in vitro. To select suitable culture media, microbial communities were assembled and cultured in seven different media at 37 °C for 36 h. Among the seven media, Bryant & Burkey (BB) and Gifu Anaerobic Media (GAM) were selected considering their microbial biomass and bacterial composition. The communities were again assembled and cultured in these two media with mucin-agar. The results showed that some bacterial genus such as Bifidobacterium, Collinsella, and Roseburia could efficiently colonize in the solid mucin-agar part while Enterococcus, Clostridium, and Veilonella dominated in the liquid part. Metabolic functional prediction for the microbial community in each medium part showed that the gene expression involved in metabolism and cell motility pathways were distinctively differentiated between the liquid and solid medium part, and the functional potential was highly related to the microbial composition. The current results demonstrate that the simulation of the gut microbial ecosystem in vitro can be beneficial to the mucosal environment mimicking and the study on the mechanistic potential of the human gut microbiota for easy translation of microbiome research to therapies.

Synthetic gut microbiome: Advances and challenges.

An exponential rise in studies regarding the association among human gut microbial communities, human health, and diseases is currently attracting the attention of researchers to focus on human gut microbiome research. However, even with the ever-growing number of studies on the human gut microbiome, translation into improved health is progressing slowly. This hampering is due to the complexities of the human gut microbiome, which is composed of >1,000 species of microorganisms, such as bacteria, archaea, viruses, and fungi. To overcome this complexity, it is necessary to reduce the gut microbiome, which can help simplify experimental variables to an extent, such that they can be deliberately manipulated and controlled. Reconstruction of synthetic or established gut microbial communities would make it easier to understand the structure, stability, and functional activities of the complex microbial community of the human gut. Here, we provide an overview of the developments and challenges of the synthetic human gut microbiome, and propose the incorporation of multi-omics and mathematical methods in a better synthetic gut ecosystem design, for easy translation of microbiome information to therapies.

Expression Patterns and Potential Biological Roles of Dip2a.

Disconnected (disco)-interacting protein 2 homolog A is a member of the DIP2 protein family encoded by Dip2a gene. Dip2a expression pattern has never been systematically studied. Functions of Dip2a in embryonic development and adult are not known. To investigate Dip2a gene expression and function in embryo and adult, a Dip2a-LacZ mouse model was generated by insertion of ß-Gal cDNA after Dip2a promoter using CRISPR/Cas9 technology. Dip2a-LacZ mouse was designed to be a lacZ reporter mouse as well as a Dip2a knockout mouse. Heterozygous mice were used to study endogenous Dip2a expression and homozygotes to study DIP2A-associated structure and function. LacZ staining indicated that Dip2a is broadly expressed in neuronal, reproductive and vascular tissues, as well as in heart, kidney, liver and lung. Results demonstrate that Dip2a is expressed in ectoderm-derived tissues in developing embryos. Adult tissues showed rich staining in neurons, mesenchymal, endothelial, smooth muscle cells and cardiomyocytes by cell types. The expression pattern highly overlaps with FSTL1 and supports previous report that DIP2A to be potential receptor of FSTL1 and its protective roles of cardiomyocytes. Broad and intense embryonic and adult expression of Dip2a has implied their multiple structural and physiological roles.