Roseburia intestinalis Modulates PYY Expression in a New a Multicellular Model including Enteroendocrine Cells

Abstract

The gut microbiota contributes to human health and disease; however, the mechanisms by which commensal bacteria interact with the host are still unclear. To date, a number of in vitro systems have been designed to investigate the host–microbe interactions. In most of the intestinal models, the enteroendocrine cells, considered as a potential link between gut bacteria and several human diseases, were missing. In the present study, we have generated a new model by adding enteroendocrine cells (ECC) of L-type (NCI-H716) to the one that we have previously described including enterocytes, mucus, and M cells. After 21 days of culture with the other cells, enteroendocrine-differentiated NCI-H716 cells showed neuropods at their basolateral side and expressed their specific genes encoding proglucagon (GCG) and chromogranin A (CHGA). We showed that this model could be stimulated by commensal bacteria playing a key role in health, Roseburia intestinalis and Bacteroides fragilis, but also by a pathogenic strain such as Salmonella Heidelberg. Moreover, using cell-free supernatants of B. fragilis and R. intestinalis, we have shown that R. intestinalis supernatant induced a significant increase in IL-8 and PYY but not in GCG gene expression, while B. fragilis had no impact. Our data indicated that R. intestinalis produced short chain fatty acids (SCFAs) such as butyrate whereas B. fragilis produced more propionate. However, these SCFAs were probably not the only metabolites implicated in PYY expression since butyrate alone had no effect. In conclusion, our new quadricellular model of gut epithelium could be an effective tool to highlight potential beneficial effects of bacteria or their metabolites, in order to develop new classes of probiotics.

Digestibility of starch

“…has increased with reports showing that the abundance of these bacteria is also reduced in individuals affected by inflammatory diseases and colorectal cancers. it was found that R. intestinalis supernatant induced a significant increase in peptide tyrosine tyrosine (PYY) and compared with B. fragilis, R. intestinalis produced more butyrate whereas B. fragilis secreted more propionate and acetate [75].…”

“…resistant starch) and endogenous intestinal mucus supports the growth of specialist microbes that produce short chain fatty acids (SCFAs) and gases, causing the lowering of the pH and inhibiting pathogens [77]. Bacteroides spp., which constitute up to 30% of colonic microbiota, produce a variety of SCFAs [75]. SCFAs are vital metabolites primarily synthesized by anaerobic bacteria in the colon through the process of fermenting dietary fiber, and the type and concentration of SCFAs in the colon vary depending on the specific food consumed and the composition of the gut microbiome [1].…”

“…According to Du et al [80] and Yuan et al [81] native beans, winter squash, and pumpkin starches are the RS sources in formulations with desired fiber-like benefits like a lower digestibility. Butyrate has received particular attention for its beneficial effects on both cellular energy metabolism and intestinal homeostasis [75].…”

Complexification of In Vitro Models of Intestinal Barriers, A True Challenge for a More Accurate Alternative Approach

“…Caco-2/HT29-MTX/NCI-H716/Raji-B: One quadricellular model representing the different cell types contributing to the protection of the intestinal barrier has been recently reported [ 158 ]. This model is complex since the addition of cells has to be performed in a certain order and at certain timepoints.…”

“…The expression of MUC2, sucrase-isomaltase (SI), Matrix Metalloproteinase 15 (MMP15) and glucagon (GCG) can be assessed to confirm the presence and differentiation of the different cell types. However, little information was provided about this model for assessing its technical and functional relevance [ 158 ].…”