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Nature Communications Dec 2023Paneth cell metaplasia (PCM) typically arises in pre-existing gastrointestinal (GI) diseases; however, the mechanistic pathway that induces metaplasia and whether PCM is...
Paneth cell metaplasia (PCM) typically arises in pre-existing gastrointestinal (GI) diseases; however, the mechanistic pathway that induces metaplasia and whether PCM is initiated exclusively by disorders intrinsic to the GI tract is not well known. Here, we describe the development of PCM in a murine model of chronic myelogenous leukemia (CML) that is driven by an inducible bcr-abl oncogene. Mechanistically, CML induces a proinflammatory state within the GI tract that results in the production of epithelial-derived IL-33. The binding of IL-33 to the decoy receptor ST2 leads to IL-9 production by type 2 innate lymphoid cells (ILC2) which is directly responsible for the induction of PCM in the colon and tissue remodeling in the small intestines, characterized by goblet and tuft cell hyperplasia along with expansion of mucosal mast cells. Thus, we demonstrate that an extra-intestinal disease can trigger an ILC2/IL-9 immune circuit, which induces PCM and regulates epithelial cell fate decisions in the GI tract.
Topics: Animals; Mice; Paneth Cells; Interleukin-9; Immunity, Innate; Interleukin-33; Lymphocytes; Intestine, Small; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Metaplasia
PubMed: 38042840
DOI: 10.1038/s41467-023-43248-5 -
Frontiers in Cell and Developmental... 2023The intestinal epithelium is the first line of host defense, and its homeostasis is dependent on soluble factors that comprise the crypt niche. Antimicrobial proteins...
The intestinal epithelium is the first line of host defense, and its homeostasis is dependent on soluble factors that comprise the crypt niche. Antimicrobial proteins are one of the mediators to maintain gut homeostasis. Angiogenin-4 (Ang4) is a member of the ribonuclease A superfamily and plays a pivotal role in antimicrobial activity against gut microbiota. However, the functions of Ang4 within the intestinal crypt niche, particularly its involvement in the development of intestinal epithelial cells (IECs), remain unknown. Here, we demonstrate that Ang4 plays a significant role in maintaining Lgr5 intestinal stem cells (ISCs) and induces apoptosis of IECs in a concentration-dependent manner. We revealed that Ang4 is highly expressed by Paneth cells in the small intestine, as well as regenerating islet-derived family member-4 (Reg4) expressing goblet cells in the colon, and both cell subsets highly contribute to ISC maintenance. Functional analysis using intestinal organoids revealed that Ang4 induces Wnt and Notch signaling, increases Lgr5 stem cell expansion, and promotes organoid growth. Furthermore, high concentrations of Ang4 induced apoptosis in the IEC cell line and organoids. Collectively, we propose that Ang4 is a dual functional protein and is a novel member of the crypt niche factor that promotes the expansion of ISCs and induces apoptosis.
PubMed: 38020881
DOI: 10.3389/fcell.2023.1181145 -
Gut Microbes Dec 2023Classically, Axin1 is considered a regulator of Wnt/β-catenin signaling. However, Axin1's roles in host-microbial interactions have been unknown. Our recent study has...
Classically, Axin1 is considered a regulator of Wnt/β-catenin signaling. However, Axin1's roles in host-microbial interactions have been unknown. Our recent study has demonstrated that deletion of intestinal epithelial Axin1 in epithelial cells and Paneth cells protects the host against colitis by enhancing . Loss of intestinal epithelial or Paneth cell Axin1 results in increased Wnt/β-catenin signaling, proliferation, and cell migration. This is associated with morphologically altered goblet and Paneth cells, including increased Muc2 and decreased lysozyme. Axin1 deletion specifically enriched . in Axin1 knockout mice is the driver of protection against DSS-induced inflammation. Here, we feature several significant conceptual changes, such as differences between Axin1 and Axin2, Axin1 in innate immunity and microbial homeostasis, and Axin1 reduction of . We discuss an important trend in the field related to Paneth cells and tissue-specific Axin1 manipulation of microbiome in health and inflammation.
Topics: Animals; Mice; Axin Protein; beta Catenin; Colitis; Gastrointestinal Microbiome; Inflammation; Microbiota; Paneth Cells
PubMed: 38010886
DOI: 10.1080/19490976.2023.2286674 -
Journal of Translational Medicine Nov 2023Mammalian intestinal epithelium constantly undergoes rapid self-renewal and regeneration sustained by intestinal stem cells (ISCs) within crypts. Inducible nitric oxide...
BACKGROUND
Mammalian intestinal epithelium constantly undergoes rapid self-renewal and regeneration sustained by intestinal stem cells (ISCs) within crypts. Inducible nitric oxide synthase (iNOS) is an important regulator in tissue homeostasis and inflammation. However, the functions of iNOS on ISCs have not been clarified. Here, we aimed to investigate the expression pattern of inducible nitric oxide synthase (iNOS) within crypts and explore its function in the homeostatic maintenance of the ISC niche.
METHODS
Expression of iNOS was determined by tissue staining and qPCR. iNOS and Lgr5 transgenic mice were used to explore the influence of iNOS ablation on ISC proliferation and differentiation. Enteroids were cultured to study the effect of iNOS on ISCs in vitro. Ileum samples from wild-type and iNOS mice were collected for RNA-Seq to explore the molecular mechanisms by which iNOS regulates ISCs.
RESULTS
iNOS was physiologically expressed in Paneth cells. Knockout of iNOS led to apparent morphological changes in the intestine, including a decrease in the small intestine length and in the heights of both villi and crypts. Knockout of iNOS decreased the number of Ki67 or BrdU proliferative cells in crypts. Loss of iNOS increased the number of Olfm4 ISCs but inhibited the differentiation and migration of Lgr5 ISCs in vivo. iNOS depletion also inhibited enteroid formation and the budding efficiency of crypts in vitro. Moreover, iNOS deficiency altered gluconeogenesis and the adaptive immune response in the ileum transcriptome.
CONCLUSION
Paneth cell-derived iNOS is required to maintain a healthy ISC niche, and Knockout of iNOS hinders ISC function in mice. Therefore, iNOS represents a potential target for the development of new drugs and other therapeutic interventions for intestinal disorders.
Topics: Animals; Mice; Homeostasis; Intestinal Mucosa; Intestines; Mammals; Mice, Knockout; Mice, Transgenic; Nitric Oxide Synthase Type II; Paneth Cells; Receptors, G-Protein-Coupled; Stem Cell Niche
PubMed: 38007452
DOI: 10.1186/s12967-023-04744-w -
Science Advances Nov 2023The mammalian intestine is one of the most rapidly self-renewing tissues, driven by stem cells residing at the crypt bottom. Paneth cells form a major element of the...
The mammalian intestine is one of the most rapidly self-renewing tissues, driven by stem cells residing at the crypt bottom. Paneth cells form a major element of the niche microenvironment providing various growth factors to orchestrate intestinal stem cell homeostasis, such as Wnt3. Different Wnt ligands can selectively activate β-catenin-dependent (canonical) or -independent (noncanonical) signaling. Here, we report that the Dishevelled-associated activator of morphogenesis 1 (Daam1) and its paralogue Daam2 asymmetrically regulate canonical and noncanonical Wnt (Wnt/PCP) signaling. Daam1/2 interacts with the Wnt inhibitor RNF43, and Daam1/2 double knockout stimulates canonical Wnt signaling by preventing RNF43-dependent degradation of the Wnt receptor, Frizzled (Fzd). Single-cell RNA sequencing analysis revealed that Paneth cell differentiation is impaired by Daam1/2 depletion because of defective Wnt/PCP signaling. Together, we identified Daam1/2 as an unexpected hub molecule coordinating both canonical and noncanonical Wnt, which is fundamental for specifying an adequate number of Paneth cells.
Topics: Animals; Wnt Signaling Pathway; Paneth Cells; Intestines; Cell Differentiation; Stem Cells; Mammals
PubMed: 38000028
DOI: 10.1126/sciadv.adh9673 -
Microbiome Nov 2023Intestinal epithelial cell (IEC) mitochondrial dysfunction involvement in inflammatory bowel diseases (IBD), including Crohn's disease affecting the small intestine, is...
BACKGROUND
Intestinal epithelial cell (IEC) mitochondrial dysfunction involvement in inflammatory bowel diseases (IBD), including Crohn's disease affecting the small intestine, is emerging in recent studies. As the interface between the self and the gut microbiota, IECs serve as hubs of bidirectional cross-talk between host and luminal microbiota. However, the role of mitochondrial-microbiota interaction in the ileum is largely unexplored. Prohibitin 1 (PHB1), a chaperone protein of the inner mitochondrial membrane required for optimal electron transport chain function, is decreased during IBD. We previously demonstrated that mice deficient in PHB1 specifically in IECs (Phb1) exhibited mitochondrial impairment, Paneth cell defects, gut microbiota dysbiosis, and spontaneous inflammation in the ileum (ileitis). Mice deficient in PHB1 in Paneth cells (epithelial secretory cells of the small intestine; Phb1) also exhibited mitochondrial impairment, Paneth cell defects, and spontaneous ileitis. Here, we determined whether this phenotype is driven by Phb1 deficiency-associated ileal microbiota alterations or direct effects of loss of PHB1 in host IECs.
RESULTS
Depletion of gut microbiota by broad-spectrum antibiotic treatment in Phb1 or Phb1 mice revealed a necessary role of microbiota to cause ileitis. Using germ-free mice colonized with ileal microbiota from Phb1-deficient mice, we show that this microbiota could not independently induce ileitis without host mitochondrial dysfunction. The luminal microbiota phenotype of Phb1 mice included a loss of the short-chain fatty acid butyrate. Supplementation of butyrate in Phb1-deficient mice ameliorated Paneth cell abnormalities and ileitis. Phb1-deficient ileal enteroid models suggest deleterious epithelial-intrinsic responses to ileal microbiota that were protected by butyrate.
CONCLUSIONS
These results suggest a mutual and essential reinforcing interplay of gut microbiota and host IEC, including Paneth cell, mitochondrial health in influencing ileitis. Restoration of butyrate is a potential therapeutic option in Crohn's disease patients harboring epithelial cell mitochondrial dysfunction. Video Abstract.
Topics: Humans; Animals; Mice; Crohn Disease; Gastrointestinal Microbiome; Ileitis; Inflammation; Inflammatory Bowel Diseases; Paneth Cells; Butyrates; Mitochondria; Intestinal Mucosa
PubMed: 37978573
DOI: 10.1186/s40168-023-01686-9 -
Proceedings of the National Academy of... Nov 2023To mediate critical host-microbe interactions in the human small intestine, Paneth cells constitutively produce abundant levels of α-defensins and other antimicrobials....
To mediate critical host-microbe interactions in the human small intestine, Paneth cells constitutively produce abundant levels of α-defensins and other antimicrobials. We report that the expression profile of these antimicrobials is dramatically askew in human small intestinal organoids (enteroids) as compared to that in paired tissue from which they are derived, with a reduction of α-defensins to nearly undetectable levels. Murine enteroids, however, recapitulate the expression profile of Paneth cell α-defensins seen in tissue. WNT/TCF signaling has been found to be instrumental in the regulation of α-defensins, yet in human enteroids exogenous stimulation of WNT signaling appears insufficient to rescue α-defensin expression. By stark contrast, forkhead box O (FOXO) inhibitor AS1842856 induced the expression of α-defensin mRNA in enteroids by >100,000-fold, restoring and to levels comparable to those found in primary human tissue. These results newly identify FOXO signaling as a pathway of biological and potentially therapeutic relevance for the regulation of human Paneth cell α-defensins in health and disease.
Topics: Humans; Animals; Mice; alpha-Defensins; Intestines; Intestine, Small; Paneth Cells; Anti-Infective Agents; Organoids
PubMed: 37956278
DOI: 10.1073/pnas.2312453120 -
Stem Cells and Development Jan 2024The homeostasis of the intestinal epithelium heavily relies on the self-renewal and differentiation of intestinal stem cells (ISCs). Although the orchestration of these...
The homeostasis of the intestinal epithelium heavily relies on the self-renewal and differentiation of intestinal stem cells (ISCs). Although the orchestration of these processes by signaling pathways such as the Wnt, BMP, Notch, and MAPK signals has been extensively studied, the dynamics of their regulation remains unclear. Our study explores how the Wnt signaling pathway temporally regulates the differentiation of ISCs into various cell types in an intestinal organoid system. We report that the duration of Wnt exposure following Notch pathway inactivation significantly influences the differentiation direction of intestinal epithelial cells toward multiple secretory cell types, including goblet cells, enteroendocrine cells (EECs), and Paneth cells. This temporal regulation of Wnt signaling adds another layer of complexity to the combination of niche signals that govern cell fate. By manipulating this temporal signal, we have developed optimized protocols for the efficient in vitro differentiation of ISCs into EECs and goblet cells. These findings provide critical insights into the dynamic regulation of ISC differentiation and offer a robust platform for future investigations into intestinal biology and potential therapeutic applications.
Topics: Intestines; Cell Differentiation; Intestinal Mucosa; Stem Cells; Wnt Signaling Pathway; Organoids
PubMed: 37897075
DOI: 10.1089/scd.2023.0186 -
American Journal of Physiology.... Jan 2024Concentrated animal feeding operations (CAFOs) are responsible for the production of global greenhouse gases and harmful environmental pollutants including hydrogen...
Concentrated animal feeding operations (CAFOs) are responsible for the production of global greenhouse gases and harmful environmental pollutants including hydrogen sulfide, ammonia, and particulate matter. Swine farmers are frequently exposed to organic dust that is proinflammatory in the lung and are thus at greater risk of developing pneumonia, asthma, and other respiratory conditions. In addition to respiratory disease, air pollutants are directly associated with altered gastrointestinal (GI) physiology and the development of GI diseases, thereby highlighting the gut-lung axis in disease progression. Instillation of hog dust extract (HDE) for 3 wk has been reported to promote the development of chronic airway inflammation in mice, however, the impact of HDE exposure on intestinal homeostasis is poorly understood. We report that 3-wk intranasal exposure of HDE is associated with increased intestinal macromolecule permeability and elevated serum endotoxin concentrations in C57BL/6J mice. In vivo studies also indicated mislocalization of the epithelial cell adhesion protein, E-cadherin, in the colon as well as an increase in the proinflammatory cytokine, , in the proximal colon. Moreover, mRNA expression of the Paneth cell-associated marker, , was increased the proximal colon, whereas the expression of the goblet cell marker, , was unchanged in the epithelial cells of the ileum, cecum, and distal colon. These results demonstrate that airway exposure to CAFOs dusts promote airway inflammation and modify the gastrointestinal tract to increase intestinal permeability, induce systemic endotoxemia, and promote intestinal inflammation. Therefore, this study identifies complex physiological consequences of chronic exposure to organic dusts derived from CAFOs on the gut-lung axis. Agricultural workers have a higher prevalence of occupational respiratory symptoms and are at greater risk of developing respiratory diseases. However, gastrointestinal complications have also been reported, yet the intestinal pathophysiology is understudied. This work is novel because it emphasizes the role of an inhaled environmental pollutant on the development of intestinal pathophysiological outcomes. This work will provide foundation for other studies evaluating how agricultural dusts disrupts host physiology and promotes debilitating gastrointestinal and systemic disorders.
Topics: Mice; Animals; Swine; Dust; Tumor Necrosis Factor-alpha; Endotoxemia; Mice, Inbred C57BL; Inflammation
PubMed: 37874654
DOI: 10.1152/ajpgi.00297.2022 -
BioRxiv : the Preprint Server For... Nov 2023According to conventional views, colon cancer originates from stem cells. However, inflammation, a key risk factor for colon cancer, was shown to suppress intestinal...
According to conventional views, colon cancer originates from stem cells. However, inflammation, a key risk factor for colon cancer, was shown to suppress intestinal stemness. Here, we employed Paneth cells (PCs) as a model to assess the capacity of differentiated lineages to trigger tumorigenesis in the context of inflammation. Upon inflammation, PC-specific Apc mutations led to intestinal tumors reminiscent not only of those arising in inflammatory bowel disease (IBD) patients but also of a larger fraction of sporadic colon cancers. The latter is likely due to the inflammatory consequences of Western-style dietary habits, the major colon cancer risk factor. Computational methods designed to predict the cell-of-origin of cancer confirmed that, in a substantial fraction of sporadic colon cancers the cells-of-origin are secretory lineages and not stem cells.
PubMed: 37873142
DOI: 10.1101/2023.10.02.560432