Rotavirus is the main cause of viral gastroenteritis in young children. Therefore, the development of inexpensive antiviral products for the prevention and/or treatment of rotavirus disease remains a priority. Previously we have shown that a recombinant monovalent antibody fragment (referred to as Anti-Rotavirus Proteins or ARP1) derived from a heavy chain antibody of a llama immunised with rotavirus was able to neutralise rotavirus infection in a mouse model system.
View Article and Find Full Text PDFThe goal of the present study was to elucidate the mechanisms of immunoregulation by which dietary punicic acid (PUA) prevents or ameliorates experimental inflammatory bowel disease (IBD). The expression of PPARγ and δ, their responsive genes and pro-inflammatory cytokines was assayed in the colonic mucosa. Immune cell-specific PPARγ null, PPARδ knockout and wild-type mice were treated with PUA and challenged with 2·5 % dextran sodium sulphate (DSS).
View Article and Find Full Text PDFOur goal in this study was to determine the potential for dietary fibers to prevent gut inflammation in IL-10-deficient (IL-10(-/-)) mice. C57BL/6J wild-type (WT) mice (n = 90) and IL-10(-/-) mice (n = 185) were assigned to a control diet or diets supplemented with PROMITOR soluble corn fiber (SCF), STA-LITE III polydextrose (PDX), Biogum (BG), Pullulan (PI-20), PROMITOR resistant starch-75 (RS-75), SCF&BG, RS-75&BG, and inulin (4 g fiber/100 g diet). On d 47, spleen, mesenteric lymph nodes (MLN), duodenum, jejunum, ileum, and colon were macroscopically and histologically evaluated.
View Article and Find Full Text PDFExpression of the mucin MUC2, the structural component of the colonic mucus layer, is lowered in ulcerative colitis. Furthermore, interleukin (IL)-10 knockout (IL-10-/-) mice develop colitis and have reduced Muc2 levels. Our aim was to obtain insight into the role of Muc2 and IL-10 in epithelial protection.
View Article and Find Full Text PDFAppetite suppressants may be one strategy in the fight against obesity. This study evaluated whether Korean pine nut free fatty acids (FFA) and triglycerides (TG) work as an appetite suppressant. Korean pine nut FFA were evaluated in STC-1 cell culture for their ability to increase cholecystokinin (CCK-8) secretion vs.
View Article and Find Full Text PDFCyclooxygenases (COXs) play a significant role in many different viral infections with respect to replication and pathogenesis. Here we investigated the role of COXs in the mouse hepatitis coronavirus (MHV) infection cycle. Blocking COX activity by different inhibitors or by RNA interference affected MHV infection in different cells.
View Article and Find Full Text PDFIn the current study we aimed to gain insight into epithelial-mesenchymal cross-talk and progenitor compartment modulation during doxorubicin (DOX)-induced mucositis in mice. Intestinal segments were collected on various days after DOX treatment. DOX-induced damage at day 1-2 was characterized by increased epithelial proliferation and apoptosis and a decrease in the expression of epithelial differentiation markers.
View Article and Find Full Text PDFObjectives: Bowel segments distal to a congenital intestinal obstruction have been suggested to be immature. In other words, luminal components such as amniotic fluid (before birth) and/or enteral nutrition (after birth) may be required to activate intestinal epithelial protein expression, thereby influencing epithelial differentiation. We investigated cell-type-specific protein expression proximal and distal to jejunal and ileal atresias in human newborns.
View Article and Find Full Text PDFThe mucin Muc2 or Mycin2 (Muc2), which is the main structural component of the protective mucus layer, has shown to be upregulated during chemotherapy-induced mucositis. As Muc2 has shown to have protective capacities, upregulation of Muc2 may be a counter reaction of the intestine protecting against mucositis. Therefore, increasing Muc2 protein levels could be a therapeutic target in mucositis prevention or reduction.
View Article and Find Full Text PDFBackground & Aims: Expression of mucin MUC2, the structural component of the colonic mucus layer, is lowered in inflammatory bowel disease. Our aim was to obtain insight in the role of Muc2 in epithelial protection.
Methods: Muc2 knockout (Muc2(-/-)) and Muc2 heterozygous (Muc2(+/-)) mice were characterized and challenged by a colitis-inducing agent, dextran sulfate sodium (DSS).
Conjugated linoleic acid (CLA) is able to reduce adiposity by affecting lipid metabolism. In particular, CLA administration to mice reduces body fat mass with a concomitant lipid accumulation in the liver. We investigated the effects of CLA on the activity of the mitochondrial citrate carrier (CIC), which is implicated in hepatic lipogenesis.
View Article and Find Full Text PDFThe use of high doses of the anti-cancer drug methotrexate (MTX) is associated with intestinal damage. As a result, mucosal immune cells become increasingly exposed to a vast amount of microbial stimuli. We aimed at determining whether these cells are still functional during MTX treatment.
View Article and Find Full Text PDFChemotherapy-induced intestinal damage is a very important dose-limiting side effect for which there is no definitive prophylaxis or treatment. This is in part due to the lack of understanding of its pathophysiology and impact on intestinal differentiation. The objective of this study was to investigate the gene expression of the small intestinal transcription factors HNF-1alpha, Cdx2, GATA-4 in an experimental model of methotrexate (MTX)-induced intestinal damage, and to correlate these alterations with histological damage, epithelial proliferation and differentiation.
View Article and Find Full Text PDFWe have investigated how gastric H. pylori infection affects antrum secretory cell types by studying the expression of secretory proteins in antrum epithelium. Antrum biopsy specimens were prospectively collected from 102 individuals (49 H.
View Article and Find Full Text PDFRotaviruses are the leading cause of severe viral gastroenteritis in young children. To gain insight in goblet cell homeostasis and intestinal mucin expression during rotavirus infection, 6-day-old mice were inoculated with murine rotavirus. To determine epithelial cell migration, mice were injected with BrdU just before inoculation.
View Article and Find Full Text PDFBackground: Studies in rodents and some studies in humans have shown that conjugated linoleic acid (CLA), especially its trans-10, cis-12 isomer, reduces body fat content. However, some but not all studies in mice and humans (though none in rats) have found that CLA promotes insulin resistance. The molecular mechanisms responsible for these effects are unclear, and there are conflicting reports on the effects of CLA on peroxisomal proliferator-activated receptor-gamma (PPARgamma) activation and expression.
View Article and Find Full Text PDFGerm-free (GF) interleukin 10-deficient (IL-10) mice develop chronic colitis after colonization by normal enteric bacteria. Muc2 is the major structural component of the protective colonic mucus. Our aim was to determine whether primary or induced aberrations in Muc2 synthesis occur in GF IL-10 mice that develop colitis after bacterial colonization.
View Article and Find Full Text PDFMUC2, the major mucin in the intestine, is expressed early during development and shows an altered expression pattern in intestinal bowel diseases. However, the mechanisms responsible for MUC2 expression in the intestine during these events are largely unknown. Having found putative GATA binding sites in the murine Muc2 promoter and that GATA-4 is expressed in Muc2-expressing goblet cells of the mouse small intestine, we undertook to study its regulation by this transcription factor.
View Article and Find Full Text PDFJ Pediatr Gastroenterol Nutr
October 2004
Background: Adult-type hypolactasia (AH) is the most common form of disaccharidase deficiency in humans, with a prevalence that varies among ethnic groups. In Brazil, the few available studies suggest a high prevalence of this condition. The objective of this study was to determine the prevalence of AH in Brazilian patients at the Ribeirão Preto University Hospital, and to study its morphologic and functional expression.
View Article and Find Full Text PDFElevated levels of prostaglandins (PGs), products of cyclooxygenases (COXs), are found in the plasma and stool of rotavirus-infected children. We sought to determine the role of COXs, PGs, and the signal transduction pathways involved in rotavirus infection to elucidate possible new targets for antiviral therapy. Human intestinal Caco-2 cells were infected with human rotavirus Wa or simian rotavirus SA-11.
View Article and Find Full Text PDFRotavirus is the most important cause of infantile gastroenteritis. Since in vivo mucosal responses to a rotavirus infection thus far have not been extensively studied, we related viral replication in the murine small intestine to alterations in mucosal structure, epithelial cell homeostasis, cellular kinetics, and differentiation. Seven-day-old suckling BALB/c mice were inoculated with 2 x 10(4) focus-forming units of murine rotavirus and were compared to mock-infected controls.
View Article and Find Full Text PDFThe nucleotide sequence of the pMS1 clone was submitted to the GenBank Nucleotide Sequence Database under accession number AF288076. Changes in the expression of mucin genes in gastrointestinal cancers is thought to contribute to the development of the disease. In our laboratory we have shown previously that MUC5AC is aberrantly expressed in rectosigmoid villous adenomas.
View Article and Find Full Text PDFBackground And Objectives: Helicobacter pylori shows a characteristic tropism for the mucus-producing gastric epithelium. In infected patients, H. pylori colocalizes in situ with the gastric secretory mucin MUC5AC.
View Article and Find Full Text PDFBackground And Aims: Severe gastrointestinal damage often complicates the use of chemotherapeutic agents such as methotrexate for anticancer treatment. Psychologic stress is known to be detrimental to normal intestinal physiology. We set out to determine if psychologic stress adds to the intestinal damage provoked by chemotherapy.
View Article and Find Full Text PDFThe origin of gastric metaplasia of the duodenum (GMD) remains enigmatic. We studied expression of mucins and trefoil peptides in GMD to gain insight into its phenotype and origin. We examined duodenal tissue of 95 patients (0 to 83 years old, 26 with gastric Helicobacter pylori infection) for the presence of GMD.
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