Project description:The gut microbiota, immune system, and enteric nervous system interact to regulate adult gut physiology. Yet the mechanisms establishing gut physiology during development remain unknown. We report that in developing zebrafish, enteroendocrine cells produced IL-22 in response to microbial signals before lymphocytes populate the gut. In larvae, IL-22 shaped the gut microbiota, increased Lactobacillaceae abundance and ghrelin expression to promote gut motility. Impaired motility and ghrelin expression were restored in il22-/- zebrafish by transfer of microbiota from wild-type zebrafish or by monoassociation with Lactobacillus plantarum. IL-22-deficient mice had impaired gut motility and reduced ghrelin expression in early life too, indicating a conserved function. Thus, before immune system maturation, enteroendocrine cells regulate early-life gut function by controlling the microbiota via IL-22.
Project description:We compared gene expression in the small intestine (ileum) of mice that were either (i) germ-free, (ii) colonized with a conventional mouse cecal microbiota, (iii) colonized with a conventional zebrafish gut microbiota, or (iv) colonized with Pseudomonas aeruginosa PAO1. Experiment Overall Design: Adult germ-free NMRI mice were colonized with either (i) a conventional mouse cecal microbiota harvested from adult Swiss-Webster mice (5 biological replicates), (ii) a conventional zebrafish intestinal microbiota harvested from adult C32 zebrafish (3 biological replicates), or (iii) a culture of Pseudomonas aeruginosa PAO1 (5 biological replicates). 14 days after colonization, total RNA was prepared from the ileum of each animal, with total RNA prepared from adult germ-free NMRI mouse ileum serving as negative controls (5 biological replicates). RNA was used as template to generate cRNA for hybridization to Affymetrix 430 v2 Mouse GeneChips.
Project description:Animals host symbiotic microbial communities that shape gut health. However, how the host immune system and microbiota interact to regulate epithelial homeostasis, particularly during early development, remains unclear. Human interleukin-26 (IL-26) is associated with gut inflammation and has intrinsic bactericidal activity in vitro, yet its in vivo functions are largely unknown, primarily due to its absence in rodents. To examine the role of IL-26 in early life, we used zebrafish and found that gut epithelial cells in il26-/- larvae exhibited increased proliferation, faster turnover, elevated and DNA damage response, and altered cell population abundance. This epithelial dysregulation occurred independently of the IL-26 canonical receptor and resulted from dysbiosis in il26-/-. Moreover, IL-26 bactericidal activity was conserved in zebrafish, suggesting a potential role of this property in regulating microbiota composition. We further identified innate lymphoid cells (ILCs) as the primary source of IL-26 at this developmental stage. These findings establish IL-26 as a central player in a regulatory circuit linking the microbiota, ILCs, and intestinal epithelial cells to maintain gut homeostasis during early life.
Project description:Animals host symbiotic microbial communities that shape gut health. However, how the host immune system and microbiota interact to regulate epithelial homeostasis, particularly during early development, remains unclear. Human interleukin-26 (IL-26) is associated with gut inflammation and has intrinsic bactericidal activity in vitro, yet its in vivo functions are largely unknown, primarily due to its absence in rodents. To examine the role of IL-26 in early life, we used zebrafish and found that gut epithelial cells in il26-/- larvae exhibited increased proliferation, faster turnover, elevated and DNA damage response, and altered cell population abundance. This epithelial dysregulation occurred independently of the IL-26 canonical receptor and resulted from dysbiosis in il26-/-. Moreover, IL-26 bactericidal activity was conserved in zebrafish, suggesting a potential role of this property in regulating microbiota composition. We further identified innate lymphoid cells (ILCs) as the primary source of IL-26 at this developmental stage. These findings establish IL-26 as a central player in a regulatory circuit linking the microbiota, ILCs, and intestinal epithelial cells to maintain gut homeostasis during early life.
Project description:Animals host symbiotic microbial communities that shape gut health. However, how the host immune system and microbiota interact to regulate epithelial homeostasis, particularly during early development, remains unclear. Human interleukin-26 (IL-26) is associated with gut inflammation and has intrinsic bactericidal activity in vitro, yet its in vivo functions are largely unknown, primarily due to its absence in rodents. To examine the role of IL-26 in early life, we used zebrafish and found that gut epithelial cells in il26-/- larvae exhibited increased proliferation, faster turnover, elevated and DNA damage response, and altered cell population abundance. This epithelial dysregulation occurred independently of the IL-26 canonical receptor and resulted from dysbiosis in il26-/-. Moreover, IL-26 bactericidal activity was conserved in zebrafish, suggesting a potential role of this property in regulating microbiota composition. We further identified innate lymphoid cells (ILCs) as the primary source of IL-26 at this developmental stage. These findings establish IL-26 as a central player in a regulatory circuit linking the microbiota, ILCs, and intestinal epithelial cells to maintain gut homeostasis during early life.
Project description:Animals host symbiotic microbial communities that shape gut health. However, how the host immune system and microbiota interact to regulate epithelial homeostasis, particularly during early development, remains unclear. Human interleukin-26 (IL-26) is associated with gut inflammation and has intrinsic bactericidal activity in vitro, yet its in vivo functions are largely unknown, primarily due to its absence in rodents. To examine the role of IL-26 in early life, we used zebrafish and found that gut epithelial cells in il26-/- larvae exhibited increased proliferation, faster turnover, elevated and DNA damage response, and altered cell population abundance. This epithelial dysregulation occurred independently of the IL-26 canonical receptor and resulted from dysbiosis in il26-/-. Moreover, IL-26 bactericidal activity was conserved in zebrafish, suggesting a potential role of this property in regulating microbiota composition. We further identified innate lymphoid cells (ILCs) as the primary source of IL-26 at this developmental stage. These findings establish IL-26 as a central player in a regulatory circuit linking the microbiota, ILCs, and intestinal epithelial cells to maintain gut homeostasis during early life.
Project description:We compared gene expression in the small intestine (ileum) of mice that were either (i) germ-free, (ii) colonized with a conventional mouse cecal microbiota, (iii) colonized with a conventional zebrafish gut microbiota, or (iv) colonized with Pseudomonas aeruginosa PAO1. Keywords: response to microbial colonization
Project description:In this study we investigated whether gut microbiota profile of Italian healthy volunteers could differ based on their geaographical origin. To this purpose, fecal samples were collected from 31 healthy individuals living in 3 different italian regions (Lombardy, North; Lazio, Center; Apulia, South) and their respective microbiota profiles were analyzed employing 16S metagenomic sequencing method. This study identifies differences in the gut microbiota content and richness among individuals with the same ethnicity coming from three different Italian regions.
Project description:We have previously demonstrated that the gut microbiota can play a role in the pathogenesis of conditions associated with exposure to environmental pollutants. It is well accepted that diets high in fermentable fibers such as inulin can beneficially modulate the gut microbiota and lessen the severity of pro-inflammatory diseases. Therefore, we aimed to test the hypothesis that hyperlipidemic mice fed a diet enriched with inulin would be protected from the pro-inflammatory toxic effects of PCB 126.