Publications by authors named "Francois Boudreau"

The esophagus is protected from the hostile environment by a stratified epithelium, which renews rapidly. Homeostasis of this epithelium is ensured by a rare population of stem cells in the basal layer: Keratin 15+ (Krt15+) cells. However, little is known about the molecular mechanisms regulating their distinct features, namely self-renewal, potency and epithelial regeneration.

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Background: Many adults with type 1 (T1D) and type 2 diabetes (T2D) have inadequate sleep increasing their risk of hyperglycemia and developing complications. The objective was to identify psychosocial determinants of healthy sleep habits (HSH) among adults with T1D and T2D.

Methods: The two HSH were: avoiding screen use in bed and having sleep regularity.

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Hepatocyte nuclear factor 4-alpha (HNF4α) is a master regulator gene belonging to the nuclear receptor superfamily and is involved in regulating a wide range of critical biological processes in different organs. Structurally, the HNF4A locus is organized into two independent promoters and is subjected to alternative splicing to produce twelve distinct isoforms. However, little is known about the biological impact of each isoform and the mechanisms by which they regulate transcription.

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Background & Aims: The intestinal epithelium intrinsically renews itself ex vivo via the proliferation of Lgr5 intestinal stem cells, which is sustained by the establishment of an epithelial stem cell niche. Differentiated Paneth cells are the main source of epithelial-derived niche factor supplies and produce Wnt3 as an essential factor in supporting Lgr5 stem cell activity in the absence of redundant mesenchymal Wnts. Maturation of Paneth cells depends on canonical Wnt signaling, but few transcriptional regulators have been identified to this end.

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The transcription factor hepatocyte nuclear factor 4 A (HNF4A) controls the metabolic features of several endodermal epithelia. Both HNF4A and HNF4G are redundant in the intestine and it remains unclear whether HNF4A alone controls intestinal lipid metabolism. Here we show that intestinal HNF4A is not required for intestinal lipid metabolism per se, but unexpectedly influences whole-body energy expenditure in diet-induced obesity (DIO).

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FoxL1-Telocytes (TC) are subepithelial cells that form a network underneath the epithelium. We have shown that without inflammatory stress, mice with loss of function in the BMP signalling pathway in TC () initiated colonic neoplasia. Although TC are modulated in IBD patients, their specific role in this pathogenesis remains unclear.

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NCOR1 is a corepressor that mediates transcriptional repression through its association with nuclear receptors and specific transcription factors. Some evidence supports a role for NCOR1 in neonatal intestinal epithelium maturation and the maintenance of epithelial integrity during experimental colitis in mice. We hypothesized that NCOR1 could control colorectal cancer cell proliferation and tumorigenicity.

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Maintenance of intestinal epithelium homeostasis is a complex process because of the multicellular and molecular composition of the gastrointestinal wall and the involvement of surrounding interactive signals. The complex nature of this intestinal barrier system poses challenges in the detailed mechanistic understanding of intestinal morphogenesis and the onset of several gut pathologies, including intestinal inflammatory disorders, food allergies, and cancer. For several years, the gut scientific community has explored different alternatives in research involving animals and models consisting of cultured monolayers derived from the immortalized or cancerous origin cell lines.

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The elevated expression of the splicing regulator SRSF10 in metastatic colorectal cancer (CRC) stimulates the production of the pro-tumorigenic splice variant. We discovered a group of small molecules with an aminothiazole carboxamide core (GPS167, GPS192 and others) that decrease production of . While additional alternative splicing events regulated by SRSF10 are affected by GPS167/192 in HCT116 cells (e.

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Background: The primary objective of this study was to determine the effectiveness of a 3-month web-based computer-tailored intervention on moderate-to-vigorous physical activity (MVPA) in adults.

Methods: A total of 242 Canadian adults aged between 35 and 70 years were randomized to an experimental group receiving the intervention or a waiting list control group. The fully automated web-based computer-tailored physical activity intervention consists of seven 10- to 15-min sessions over an 8-week period.

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We have previously reported that histone deacetylase epigenetic regulator and deletion in intestinal epithelial cells (IEC) disrupts mucosal tissue architecture and barrier, causing chronic inflammation. In this study, proteome and transcriptome analysis revealed the importance of signaling pathways induced upon genetic IEC- and deletion. Indeed, Gene Ontology biological process analysis of enriched deficient IEC RNA and proteins identified common pathways, including lipid metabolic and oxidation-reduction process, cell adhesion, and antigen processing and presentation, related to immune responses, correlating with dysregulation of major histocompatibility complex (MHC) class II genes.

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Background & Aims: Recent evidence has suggested that the intact intestinal epithelial barrier protects our body from a range of immune-mediated diseases. The epithelial layer has an impressive ability to reconstitute and repair upon damage and this process of repair increasingly is seen as a therapeutic target. In vitro models to study this process in primary intestinal cells are lacking.

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HNF4α is a nuclear receptor produced as 12 isoforms from two promoters by alternative splicing. To characterize the transcriptional capacities of all 12 HNF4α isoforms, stable lines expressing each isoform were generated. The entire transcriptome associated with each isoform was analyzed as well as their respective interacting proteome.

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When developing an innovative intervention, its acceptability to patients, health care professionals and managers must be considered to ensure the implementation into practice. This study aims to identify factors influencing the acceptability of a computer-tailored and pedometer-based socio-cognitive intervention for patients with heart disease. Focus group interviews were conducted in two outlying regions of the province of Quebec (Canada).

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Hepatocyte nuclear factor 4α (HNF4α) is a transcription factor that acts as a master regulator of genes for several endoderm-derived tissues, including the intestine, in which it plays a central role during development and tumorigenesis. To better define the mechanisms by which HNF4α can influence these processes, we identified proteins interacting with HNF4α using stable isotope labelling with amino acids in cell culture (SILAC)-based quantitative proteomics with either immunoprecipitation of green fluorescent protein (GFP) or with proximity-dependent purification by the biotin ligase BirA (BioID), both fused to HNF4α. Surprisingly, these analyses identified a significant enrichment of proteins characterized with a role in DNA repair, a so far unidentified biological feature of this transcription factor.

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Both HDAC1 and HDAC2 are class I deacetylases acting as erasers of lysine-acetyl marks on histones and non-histone proteins. Several histone deacetylase inhibitors, either endogenous to the cell, such as the ketogenic β-hydroxybutyrate metabolite, or exogenous, such as butyrate, a microbial-derived metabolite, regulate HDAC activity. Different combinations of intestinal epithelial cell (IEC)-specific Hdac1 and/or Hdac2 deletion differentially alter mucosal homeostasis in mice.

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Mutations in the HNF4A gene cause MODY1 and are associated with an increased risk of Type 2 diabetes mellitus. On the other hand, incretins are hormones that potentiate reductions in blood glucose levels. Given the established role of incretin-based therapy to treat diabetes and metabolic disorders, we investigated a possible regulatory link between intestinal epithelial HNF4α and glucose-dependent insulinotropic polypeptide (GIP), an incretin that is specifically produced by gut enteroendocrine cells.

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HNF4α is a key nuclear receptor for regulating gene expression in the gut. Although both P1 and P2 isoform classes of HNF4α are expressed in colonic epithelium, specific inhibition of P1 isoforms is commonly found in colorectal cancer. Previous studies have suggested that P1 and P2 isoforms might regulate different cellular functions.

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Colorectal tumors are immersed in an array of tumor-promoting factors including extracellular nucleotides such as uridine 5'‑diphosphate (UDP). UDP is the endogenous agonist of the G protein-coupled P2Y receptor (P2YR), which may contribute to the formation of a tumor-promoting microenvironment by coordinating resistance to apoptosis. Colorectal cancer (CRC) was chemically induced in P2ry6 knockout (P2ry6) mice using azoxymethane and dextran sulfate sodium challenges.

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Physical activity plays a crucial role in the prevention and treatment of type 2 diabetes. Therefore, it is important to understand why so few adults with type 2 diabetes regularly engage in physical activity. The role of self-regulation in the context of health-related behavior adherence, especially in terms of physical activity engagement and adherence, has largely been reviewed based on the strength energy model.

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Intestinal epithelial cells form a protective barrier in limiting gut luminal content potentially harmful to the host. Upon gut epithelium injury, several signals instruct epithelial cells to undergo a rapid healing process. Defects in this process induce inflammatory responses and can further evolve into chronic gut inflammatory diseases.

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Article Synopsis
  • The development of 3D cell cultures into organoids offers a more realistic model for studying organ function and physiology compared to traditional methods.
  • Organoids can be derived from various organs like the intestine, brain, and liver, allowing researchers to investigate cellular organization at a systems level using advanced profiling technologies.
  • Recent advances enable detailed characterization of organoids, aiding in understanding disease mechanisms and cellular responses in conditions that closely mimic in vivo environments.
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Purpose: Hepatocyte nuclear factor 1 alpha (HNF1α) defects cause Mature Onset Diabetes of the Young type 3 (MODY3), characterized by defects in beta-cell insulin secretion. However, HNF1α is involved in many other metabolic pathways with relevance for monogenic or polygenic type 2 diabetes. We aimed to investigate gut hormones, lipids, and insulin regulation in response to a meal test in HNF1α defect carriers (MODY3) compared to non-diabetic subjects (controls) and type 2 diabetes (T2D).

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Shp-1 (Src homology region 2 domain-containing protein tyrosine phosphatase-1) is a phosphatase that is highly expressed in hematopoietic and epithelial cells. Whereas its function is largely characterized in hematopoietic cells, its role in epithelial cells, such as intestinal epithelial cells (IECs), is not well known. Here, we generated mice with an IEC-specific knockout of (Src homology region 2 domain-containing phosphatase-1; ).

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