Vitamin D Is Necessary for Murine Gastric Epithelial Homeostasis.
Ontology highlight
ABSTRACT:
SUBMITTER: Ali II
PROVIDER: S-EPMC8389223 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The iron deficiency anaemia that often accompanies infection with Helicobacter pylori may reflect increased uptake of iron into gastric epithelial cells. Here we show an infection-associated increase in total intracellular iron levels was associated with the redistribution of the transferrin receptor from the cell cytosol to the cell surface, and with increased levels of ferritin, an intracellular iron storage protein that corresponded with a significant increase in lysosomal stores of labile iron. In contrast, the pool of cytosolic labile iron was significantly decreased in infected cells. These changes in intracellular iron distribution were associated with the uptake and trafficking of H. pylori through the cells, and enhanced in strains capable of expressing the cagA virulence gene. We speculate that degradation of lysosomal ferritin may facilitate H. pylori pathogenesis, in addition to contributing to bacterial persistence in the human stomach.
| S-EPMC5584798 | biostudies-literature
Project description:Opportunistic lung infection and inflammation is a hallmark of chronic recreational/clinical use of morphine. We show that early induction of IL17 from the bronchial epithelium, following pathogenic encounter is a protective response, which contributes to pathogenic clearance and currently attributed to TLR2 activation in immune cells. Concurrent activation of TLR2 and IL17R in bronchial epithelium results in the sequestration of MyD88 (TLR2 adapter) by Act1/CIKS (IL17R adapter), thereby turning off TLR2 signaling to restore homeostasis. Morphine inhibits the early IL17 release and interaction between Act1 and MyD88, leading to decreased pathogenic clearance and sustained inflammation. Hence, we propose that therapeutically targeting either TLR2 or IL17 in bronchial epithelia, in the context of morphine, can restore inflammatory homeostasis.
| S-EPMC4466887 | biostudies-other
Project description:Murine models of Helicobacter pylori infection are used to study host-pathogen interactions, but lack of severe gastritis in this model has limited its usefulness in studying pathogenesis. We compared the murine gastric epithelial cell line GSM06 to the human gastric epithelial AGS cell line to determine whether similar events occur when cultured with H. pylori.The lysates of cells infected with H. pylori isolates or an isogenic cagA-deficient mutant were assessed for translocation and phosphorylation of CagA and for activation of stress pathway kinases by immunoblot.Phosphorylated CagA was detected in both cell lines within 60 minutes. Phospho-ERK 1/2 was present within several minutes and distinctly present in GSM06 cells at 60 minutes. Similar results were obtained for phospho-JNK, although the 54 kDa phosphoprotein signal was dominant in AGS, whereas the lower molecular weight band was dominant in GSM06 cells.These results demonstrate that early events in H. pylori pathogenesis occur within mouse epithelial cells similar to human cells and therefore support the use of the mouse model for the study of acute CagA-associated host cell responses. These results also indicate that reduced disease in H. pylori-infected mice may be due to lack of the Cag PAI, or by differences in the mouse response downstream of the initial activation events.
| S-EPMC4965344 | biostudies-literature
Project description:The role of ROS in stem cell biology has not been fully illustrated and understood. Here we compared the different responses and investigated the mechanism underlying oxidative stress induced by hydrogen peroxide (H2O2) between murine corneal epithelial progenitor cell line (TKE2) and mature murine corneal epithelial cells (MCE). TKE2 showed a different homeostasis and strong resistance to H2O2. TKE2 reduced the production of ROS, inhibited ROS generation enzyme NADPH oxidase 4 (NOX4), and increased dual specificity phosphatase 6 (DUSP6). Furthermore, TKE2 activated nuclear factor (erythroid-derived 2)-like 2 (NRF2) signaling pathway, regulated miR-125B1 and miR-29B1, and elevated levels of antioxidants glutathione S-transferase P (GSTP) and superoxide dismutases (SOD). The association with ROS of the cells was also verified by RNA interference approach and pharmacological antagonization. In addition, TKE2 enhanced the autophagy after exposure to H2O2. The novel evidence suggests that TKE2 cells have different homeostasis and strong antioxidant properties against oxidative stress via the regulation of ROS formation and pathway.
| S-EPMC5090348 | biostudies-literature
Project description:Vitamin D (VD) deficiency can result from insufficiency of either light exposure or VD intake. We investigated the biological effects of VD deficiency for 7 months on the mouse gastric glands. Varying degrees of VD deficiency were induced in C57BL/6 mice by keeping them on standard diet with constant-dark conditions (SDD) or VD deficient diet with constant-dark conditions (VDD). Samples of serum, glandular stomach, and gastric contents were collected for LCMS/MS, RT-PCR, immunohistochemistry, and acid content measurements. Both SDD and VDD mice had a significant decline in 25OHVD metabolite, gastric epithelial cell proliferation, and mucin 6 gene expression. These effects were enhanced with the severity of VD deficiency from SDD to VDD. Besides and compared to the control group, SDD mice only displayed a significant increase in the number of zymogenic cells (p ≤ 0.0001) and high expression of the adiponectin (p ≤ 0.05), gastrin (p ≤ 0.0001), mucin 5AC (*** p ≤ 0.001) and the Cyclin-dependent kinase inhibitor 1A (**** p ≤ 0.0001). These phenotypes were unique to SDD gastric samples and not seen in the VDD or control groups. This study suggests that the body reacts differently to diverse VD deficiency sources, light or diet.
| S-EPMC10649607 | biostudies-literature
Project description:To quantify the potential benefit of adjuvant chemotherapy (ACT) with respect to survival, and to identify factors for predicting prognoses in early gastric cancer patients. Patients with pT1 gastric cancer (GC) who underwent radical resection with D2 lymphadenectomy were retrospectively analyzed. Based on lymph node metastasis (LNM) status and treatment regimens, patients were classified into groups, and clinicopathological variables, overall survival (OS), and disease-specific survival (DSS) were compared. Of 1,050 enrolled patients, 151 patients (14.4%) had a positive LNM status. Submucosal invasion, undifferentiated state, tumor size > 2 cm, ulceration, and lymphovascular invasion were independent risk factors for LNM using multivariate analyses. The 5-year OS of all patients was 96.4%. HER2 positive, perineural invasion, and LNM were independent factors for worse survival. Patients with pT1N3 GC had a worse 5-year OS and DSS than pT1N0, pT1N1, and pT1N2 patients (P < 0.001). The 5-year OS and DSS for pT1N1 patients showed no significant difference between ACT and surgery only patients. For pT1N2 patients, the 5-year OS and DSS showed no significant difference between S-1 and Xelox treatments. For pT1N3 patients, 7 (36.8%) received S-1, while 12 (63.2%) received Xelox treatment. Patients receiving Xelox treatment showed a better 5-year OS (75.0% vs. 14.3%) and DSS (81.8% vs. 20.0%) than patients receiving S-1 (P < 0.05). Curative surgery only was adequate for patients with pT1N0 and pT1N1. Xelox showed no survival benefits for pT1N2 patients. Therefore, S-1 is the optimal choice for pT1N2 patients, when considering adverse effects. Xelox is recommended for pT1N3 patients.
| S-EPMC9088187 | biostudies-literature
Project description:Alanyl-glutamine (Ala-Gln) has recently been shown to enhance catch-up growth and gut integrity in undernourished children from Northeast Brazil. We hypothesized that the intestinal epithelial effects of Ala-Gln in malnourished weanling mice and mouse small intestinal epithelial (MSIE) cells would include modulation of barrier function, proliferation, and apoptosis. Dams of 10-day-old suckling C57BL/6 pups were randomized to a standard diet or an isocaloric Northeast Brazil "regional basic diet," moderately deficient in protein, fat, and minerals. Upon weaning to their dam's diet on day of life 21, pups were randomized to Ala-Gln solution or water. At 6 wk of age, mice were killed, and jejunal tissue was collected for morphology, immunohistochemistry, and Ussing chamber analysis of transmucosal resistance and permeability. Proliferation of MSIE cells in the presence or absence of Ala-Gln was measured by MTS and bromodeoxyuridine assays. MSIE apoptosis was assessed by annexin and 7-amino-actinomycin D staining. Pups of regional basic diet-fed dams exhibited failure to thrive. Jejunal specimens from undernourished weanlings showed decreased villous height and crypt depth, decreased transmucosal resistance, increased permeability to FITC-dextran, increased claudin-3 expression, and decreased epithelial proliferation and increased epithelial apoptosis (as measured by bromodeoxyuridine and cleaved caspase-3 staining, respectively). Undernourished weanlings supplemented with Ala-Gln showed improvements in weight velocity, villous height, crypt depth, transmucosal resistance, and epithelial proliferation/apoptosis compared with unsupplemented controls. Similarly, Ala-Gln increased proliferation and reduced apoptosis in MSIE cells. In summary, Ala-Gln promotes intestinal epithelial homeostasis in a mouse model of malnutrition-associated enteropathy, mimicking key features of the human disease.
| S-EPMC3191556 | biostudies-literature
Project description:Gastric epithelial stem cells are responsible for constant epithelial self-renewal, which is accelerated by infection with the gastric pathogen Helicobacter pylori. However, the mechanism that regulates stem cell turnover in the stomach remains unknown. Here we show that signaling by R-spondin 3 and Wnt hierarchically organizes the stem cell compartment in the antrum, producing two Wnt-responsive populations, which are either Lgr5+ve or Axin2 +ve. The positional identity of the Axin2+ve population relies on R-spondin 3 produced by stromal myofibroblasts. Increased availability of R-spondin induces hyperproliferation through specific expansion of Axin2+ve but not Lgr5+ve cells. Similarly, infection with H. pylori induces an increase in stromal R-spondin 3 expression, resulting in hyperplasia as well as shedding of bacteria that have entered the gland. This identifies a role for stromal cells in environmental sensing to orchestrate epithelial homeostasis via Wnt signaling.
2017-06-30 | GSE79494 | GEO
Project description:Vitamin E (VitE) deficiency results in embryonic lethality. Knockdown of the gene ttpa encoding for the VitE regulatory protein [?-tocopherol transfer protein (?-TTP)] in zebrafish embryos causes death within 24 h post-fertilization (hpf). To test the hypothesis that VitE, not just ?-TTP, is necessary for nervous system development, adult 5D strain zebrafish, fed either VitE sufficient (E+) or deficient (E-) diets, were spawned to obtain E+?and E- embryos, which were subjected to RNA in situ hybridization and RT-qPCR. Ttpa was expressed ubiquitously in embryos up to 12 hpf. Early gastrulation (6 hpf) assessed by goosecoid expression was unaffected by VitE status. By 24 hpf, embryos expressed ttpa in brain ventricle borders, which showed abnormal closure in E- embryos. They also displayed disrupted patterns of paired box 2a (pax2a) and SRY-box transcription factor 10 (sox10) expression in the midbrain-hindbrain boundary, spinal cord and dorsal root ganglia. In E- embryos, the collagen sheath notochord markers (col2a1a and col9a2) appeared bent. Severe developmental errors in E- embryos were characterized by improper nervous system patterning of the usually carefully programmed transcriptional signals. Histological analysis also showed developmental defects in the formation of the fore-, mid- and hindbrain and somites of E- embryos at 24 hpf. Ttpa expression profile was not altered by the VitE status demonstrating that VitE itself, and not ttpa, is required for development of the brain and peripheral nervous system in this vertebrate embryo model.
| S-EPMC7506018 | biostudies-literature
Project description:The lymphatic vascular system mediates fluid homeostasis, immune defense, and tumor metastasis. Only a handful of genes are known to affect the development of the lymphatic vasculature, and even fewer represent therapeutic targets for lymphatic diseases. Adrenomedullin (AM) is a multifunctional peptide vasodilator that transduces its effects through the calcitonin receptor-like receptor (calcrl) when the receptor is associated with a receptor activity-modifying protein (RAMP2). Here we report on the involvement of these genes in lymphangiogenesis. AM-, calcrl-, or RAMP2-null mice died mid-gestation after development of interstitial lymphedema. This conserved phenotype provided in vivo evidence that these components were required for AM signaling during embryogenesis. A conditional knockout line with loss of calcrl in endothelial cells confirmed an essential role for AM signaling in vascular development. Loss of AM signaling resulted in abnormal jugular lymphatic vessels due to reduction in lymphatic endothelial cell proliferation. Furthermore, AM caused enhanced activation of ERK signaling in human lymphatic versus blood endothelial cells, likely due to induction of CALCRL gene expression by the lymphatic transcriptional regulator Prox1. Collectively, our studies identify a class of genes involved in lymphangiogenesis that represent a pharmacologically tractable system for the treatment of lymphedema or inhibition of tumor metastasis.
| S-EPMC2147672 | biostudies-literature