Project description:The chicken gastrointestinal tract (GIT) harbours a complex microbial community, involved in several physiological processes such as host immunomodulation and feed digestion. Other studies were already performed to define the chicken gut metagenome and its fecal metaproteome. For the first time, the present study analysed dietary effects on the protein inventory of the microbiota in crop and ceca of broilers. We performed quantitative label-free metaproteomics by using 1D-gel electrophoresis coupled with LC-MS/MS to identify the structural and functional changes triggered by diets supplied with varying amount of mineral phosphorus (P) and microbial phytase (MP). Phylogenetic assessment based on label-free quantification (LFQ) values of the proteins identified Lactobacillaceae as the major family in the crop section regardless of the diet, whereas proteins belonging to the family Veillonellaceae increased with the P supplementation. Within the ceca section, proteins of Bacteroidaceae were more abundant in the P-supplied diets, whereas proteins of Eubacteriaceae decreased with the P-addition. Proteins of the Ruminococcaceae increasedraised with the amount of MP while proteins of Lactobacillaceae werewas more abundant in the MP-lacking diets. Classification of the identified proteins into COGs and KEGG pathways underlined a diverse microbiota activity depending on the dietary regimen, indicating a thriving microbial community in the case of P and MP supplementation, and stressed microbial community when no P and MP were supplied. Insights oninto the identified KEGG pathways, as well as comparison between the GIT sections, dietary treatments, and the bacterial families encoding for the pathways of interest are provided. T) harbours a complex microbial community, involved in several physiological processes such as host immunomodulation and feed digestion. Other studies were already performed to define the chicken gut metagenome and its fecal metaproteome. For the first time, the present study analysed dietary effects on the protein inventory of the microbiota in crop and ceca of broilers. We performed quantitative label-free metaproteomics by using 1D-gel electrophoresis coupled with LC-MS/MS to identify the structural and functional changes triggered by diets supplied with varying amount of mineral phosphorus (P) and microbial phytase (MP). Phylogenetic assessment based on label-free quantification (LFQ) values of the proteins identified Lactobacillaceae as the major family in the crop section regardless of the diet, whereas proteins belonging to the family Veillonellaceae increased with the P supplementation. Within the ceca section, proteins of Bacteroidaceae were more abundant in the P-supplied diets, whereas proteins of Eubacteriaceae decreased with the P-addition. Proteins of the Ruminococcaceae increasedraised with the amount of MP while proteins of Lactobacillaceae werewas more abundant in the MP-lacking diets. Classification of the identified proteins into COGs and KEGG pathways underlined a diverse microbiota activity depending on the dietary regimen, indicating a thriving microbial community in the case of P and MP supplementation, and stressed microbial community when no P and MP were supplied. Insights oninto the identified KEGG pathways, as well as comparison between the GIT sections, dietary treatments, and the bacterial families encoding for the pathways of interest are provided.
Project description:The enteric nervous system (ENS), which is derived from enteric neural crest cells (ENCCs) during gut development, represents the neuronal innervation of the gastrointestinal tract and is critical for regulating normal intestinal function. Compromised ENCC migration can lead to Hirschsprung Disease, which is characterized by an aganglionic distal bowel. We find that removal of the ceca, a paired structure present at the midgut-hindgut junction in avian intestine, leads to severe hindgut aganglionosis, suggesting that the ceca are required for ENS development. To test this, we replaced the ceca of embryonic day 6 (E6) wild-type chicks with ceca from transgenic GFP chicks. Interestingly, the entire hindgut ENS arises from the GFP+ ceca-derived ENCC population. Comparative transcriptome profiling of the cecal buds compared to the interceca region shows that the non-canonical Wnt signaling pathway is preferentially expressed within the ceca. Specifically, Wnt11 is highly expressed in the ceca, as confirmed by RNA in situ hybridization, leading us to hypothesize that cecal expression of Wnt11 is important for ENCC colonization of the hindgut. Organ cultures were prepared using E6 avian intestine, when ENCCs are migrating through the ceca, and showed that Wnt11 inhibits enteric neuronal differentiation. These results reveal an essential role for the ceca during hindgut ENS formation and highlight an important function for non-canonical Wnt signaling in regulating ENCC differentiation and thereby promoting their migration into the colon.
Project description:Pancreatic cancer is the 3rd most prevalent cause of cancer related deaths in United states alone, with over 55000 patients being diagnosed in 2019 alone and nearly as many succumbing to it. Late detection, lack of effective therapy and poor understanding of pancreatic cancer systemically contributes to its poor survival statistics. Obesity and high caloric intake linked co-morbidities like type 2 diabetes (T2D) have been attributed as being risk factors for a number of cancers including pancreatic cancer. Studies on gut microbiome has shown that lifestyle factors as well as diet has a huge effect on the microbial flora of the gut. Further, modulation of gut microbiome has been seen to contribute to effects of intensive insulin therapy in mice on high fat diet. In another study, abnormal gut microbiota was reported to contribute to development of diabetes in Db/Db mice. Recent studies indicate that microbiome and microbial dysbiosis plays a role in not only the onset of disease but also in its outcome. In colorectal cancer, Fusobacterium has been reported to promote therapy resistance. Certain intra-tumoral bacteria have also been shown to elicit chemo-resistance by metabolizing anti-cancerous agents. In pancreatic cancer, studies on altered gut microbiome have been relatively recent. Microbial dysbiosis has been observed to be associated with pancreatic tumor progression. Modulation of microbiome has been shown to affect response to anti-PD1 therapy in this disease as well. However, most of the studies in pancreatic cancer and microbiome have remained focused om immune modulation. In the current study, we observed that in a T2D mouse model, the microbiome changed significantly as the hyperglycemia developed in these animals. Our results further showed that, tumors implanted in the T2D mice responded poorly to Gemcitabine/Paclitaxel (Gem/Pac) standard of care compared to those in the control group. A metabolomic reconstruction of the WGS of the gut microbiota further revealed that an enrichment of bacterial population involved in drug metabolism in the T2D group.