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1.
Int Immunopharmacol ; 90: 107213, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33296781

ABSTRACT

BACKGROUND: Excessive ethanol consumption results in gastric mucosa damage, which could further develop into chronic gastritis, peptic ulcer, and gastric cancer in humans. Gentiopicroside (GPS), a major active component of Gentianae Macrophyllae radix, was reported to play a critical role in anti-inflammation. In the study, we aimed to investigate the functional role and underlying mechanism of GPS in ethanol-induced gastritis. METHODS: A model of gastritis was created by ethanol in C57BL/6 mice. Enzyme-linked immunosorbent assay was used to determine the concentration of TNF-α, IL-1ß, IL-8, and IL-10. RESULTS: We found that GPS treatment significantly ameliorated ethanol-induced gastritis in mice, with lower production of pro-inflammatory cytokine TNF-α, IL-1ß, and IL-8 and higher levels of anti-inflammatory cytokine IL-10. The anti-inflammatory effect of GPS was further confirmed in vitro in ethanol-treated human gastric mucosal GES cells. Mechanistically, we demonstrated that GPS regulated matrix metallopeptidase expression and pERK1/2 signaling. Knockdown of matrix metallopeptidase 10 (MMP-10) greatly improved cell survival and suppressed inflammatory response in ethanol-treated GES cells. Moreover, inhibition of pERK1/2 signaling using U0126 decreased the expression of MMP-10 in ethanol-induced gastritis. U0126 treatment also suppressed the expression of TNF-α, IL-1ß, and IL-8, and enhanced IL-10 expression in mice gastric mucosa. CONCLUSIONS: Taken together, our findings suggest that GPS ameliorates ethanol-induced gastritis via regulating MMP-10 and pERK1/2 signaling, which might provide a promising therapeutic drug for ethanol-induced gastritis.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Gastric Mucosa/drug effects , Gastritis/prevention & control , Iridoid Glucosides/pharmacology , Matrix Metalloproteinase 10/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Animals , Apoptosis/drug effects , Cell Line , Cytokines/genetics , Cytokines/metabolism , Disease Models, Animal , Ethanol , Female , Gastric Mucosa/enzymology , Gastric Mucosa/pathology , Gastritis/chemically induced , Gastritis/enzymology , Gastritis/pathology , Humans , Inflammation Mediators/metabolism , Matrix Metalloproteinase 10/genetics , Mice, Inbred C57BL , Phosphorylation , Signal Transduction
3.
Oncogene ; 39(22): 4465-4474, 2020 05.
Article in English | MEDLINE | ID: mdl-32350444

ABSTRACT

Helicobacter pylori infection is the main risk factor for the development of gastric cancer, the third leading cause of cancer death worldwide. H. pylori colonizes the human gastric mucosa and persists for decades. The inflammatory response is ineffective in clearing the infection, leading to disease progression that may result in gastric adenocarcinoma. We have shown that polyamines are regulators of the host response to H. pylori, and that spermine oxidase (SMOX), which metabolizes the polyamine spermine into spermidine plus H2O2, is associated with increased human gastric cancer risk. We now used a molecular approach to directly address the role of SMOX, and demonstrate that Smox-deficient mice exhibit significant reductions of gastric spermidine levels and H. pylori-induced inflammation. Proteomic analysis revealed that cancer was the most significantly altered functional pathway in Smox-/- gastric organoids. Moreover, there was also less DNA damage and ß-catenin activation in H. pylori-infected Smox-/- mice or gastric organoids, compared to infected wild-type animals or gastroids. The link between SMOX and ß-catenin activation was confirmed in human gastric organoids that were treated with a novel SMOX inhibitor. These findings indicate that SMOX promotes H. pylori-induced carcinogenesis by causing inflammation, DNA damage, and activation of ß-catenin signaling.


Subject(s)
Adenocarcinoma/etiology , DNA Damage , Gastritis/enzymology , Helicobacter Infections/enzymology , Helicobacter pylori/pathogenicity , Oxidoreductases Acting on CH-NH Group Donors/physiology , Spermine/metabolism , Stomach Neoplasms/etiology , Adenocarcinoma/microbiology , Animals , Cell Transformation, Neoplastic , Gastritis/genetics , Gastritis/microbiology , Gastritis/pathology , Helicobacter Infections/genetics , Helicobacter Infections/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout , Organoids , Oxidoreductases Acting on CH-NH Group Donors/deficiency , Oxidoreductases Acting on CH-NH Group Donors/genetics , Proteome , RNA, Messenger/biosynthesis , Signal Transduction , Spermidine/biosynthesis , Stomach Neoplasms/microbiology , beta Catenin/physiology , Polyamine Oxidase
4.
DNA Repair (Amst) ; 89: 102836, 2020 05.
Article in English | MEDLINE | ID: mdl-32143126

ABSTRACT

Gastric cancers are the third leading cause of cancer mortality in the world. Helicobacter pylori causes over 60 % of all stomach cancers. Colonization of the gastric mucosa by H. pylori results in increased DNA damage. Repair of DNA damage may also be reduced by H. pylori infection. Reduced DNA repair in combination with increased DNA damage can cause carcinogenic mutations. During progression to gastric cancer, gastric epithelium goes through stages of increasing pathology. Determining the levels of DNA repair enzymes during progression to gastric cancer could illuminate treatment approaches. Our aim is to determine the level of gastric expression of DNA repair proteins ERCC1 (a nucleotide excision repair enzyme) and PMS2 (a mismatch repair enzyme) in the presence of H. pylori infection at successive stages of gastric pathology and in gastric cancers. We analyzed gastric tissues of 300 individuals, including 30 without dyspepsia, 200 with dyspepsia and 70 with gastric cancers. The presence of H. pylori, gastric pathology and expression of DNA repair proteins ERCC1 and PMS2 were evaluated. Infection by H. pylori carrying the common cagA gene reduced median nuclear expression of ERCC1 and PMS2 to less than 20 % and 15 % of normal, respectively, in all pathologic stages preceding cancer. ERCC1 and PMS2 nuclear expression was 0-5 % of normal in gastric cancers. H. pylori can cause deficiency of ERCC1 and PMS2 protein expression. These deficiencies are associated with gastric pathology and cancer. This reduction in DNA repair likely causes carcinogenic mutations. Substantially reduced ERCC1 and PMS2 expression appears to be an early step in progression to H. pylori-induced gastric cancer.


Subject(s)
DNA-Binding Proteins/genetics , Endonucleases/genetics , Gastritis/genetics , Helicobacter Infections/complications , Mismatch Repair Endonuclease PMS2/genetics , Stomach Neoplasms/genetics , Adult , DNA Mismatch Repair , DNA Repair , Female , Gastritis/enzymology , Gastritis/etiology , Gastritis/microbiology , Gene Expression Regulation , Gene Expression Regulation, Neoplastic , Helicobacter pylori , Humans , Male , Middle Aged , Stomach Neoplasms/enzymology , Stomach Neoplasms/etiology , Stomach Neoplasms/microbiology
5.
Am J Physiol Gastrointest Liver Physiol ; 318(5): G931-G945, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32174134

ABSTRACT

Helicobacter pylori infection always induces gastritis, which may progress to ulcer disease or cancer. The mechanisms underlying mucosal injury by the bacteria are incompletely understood. Here, we identify a novel pathway for H. pylori-induced gastric injury, the impairment of maturation of the essential transport enzyme and cell adhesion molecule, Na-K-ATPase. Na-K-ATPase comprises α- and ß-subunits that assemble in the endoplasmic reticulum (ER) before trafficking to the plasma membrane. Attachment of H. pylori to gastric epithelial cells increased Na-K-ATPase ubiquitylation, decreased its surface and total levels, and impaired ion balance. H. pylori did not alter degradation of plasmalemma-resident Na-K-ATPase subunits or their mRNA levels. Infection decreased association of α- and ß-subunits with ER chaperone BiP and impaired assembly of α/ß-heterodimers, as was revealed by quantitative mass spectrometry and immunoblotting of immunoprecipitated complexes. The total level of BiP was not altered, and the decrease in interaction with BiP was not observed for other BiP client proteins. The H. pylori-induced decrease in Na-K-ATPase was prevented by BiP overexpression, stopping protein synthesis, or inhibiting proteasomal, but not lysosomal, protein degradation. The results indicate that H. pylori impairs chaperone-assisted maturation of newly made Na-K-ATPase subunits in the ER independently of a generalized ER stress and induces their ubiquitylation and proteasomal degradation. The decrease in Na-K-ATPase levels is also seen in vivo in the stomachs of gerbils and chronically infected children. Further understanding of H. pylori-induced Na-K-ATPase degradation will provide insights for protection against advanced disease.NEW & NOTEWORTHY This work provides evidence that Helicobacter pylori decreases levels of Na-K-ATPase, a vital transport enzyme, in gastric epithelia, both in acutely infected cultured cells and in chronically infected patients and animals. The bacteria interfere with BiP-assisted folding of newly-made Na-K-ATPase subunits in the endoplasmic reticulum, accelerating their ubiquitylation and proteasomal degradation and decreasing efficiency of the assembly of native enzyme. Decreased Na-K-ATPase expression contributes to H. pylori-induced gastric injury.


Subject(s)
Endoplasmic Reticulum/enzymology , Epithelial Cells/enzymology , Gastric Mucosa/enzymology , Gastritis/enzymology , Heat-Shock Proteins/metabolism , Helicobacter Infections/enzymology , Helicobacter pylori/pathogenicity , Sodium-Potassium-Exchanging ATPase/metabolism , Cells, Cultured , Endoplasmic Reticulum/microbiology , Endoplasmic Reticulum Chaperone BiP , Enzyme Stability , Epithelial Cells/microbiology , Gastric Mucosa/microbiology , Gastritis/genetics , Gastritis/microbiology , Helicobacter Infections/genetics , Helicobacter Infections/microbiology , Host-Pathogen Interactions , Humans , Proteasome Endopeptidase Complex/metabolism , Protein Folding , Proteolysis , Sodium-Potassium-Exchanging ATPase/genetics , Ubiquitination
6.
J Pathol ; 247(1): 35-47, 2019 01.
Article in English | MEDLINE | ID: mdl-30168144

ABSTRACT

Chronic inflammation and intestinal metaplasia are strongly associated with gastric carcinogenesis. Kras activation and Pten deletion are observed in intestinal-type gastric cancer, and Cdh1 mutation is associated with diffuse-type gastric cancer. Although various mouse models of gastric carcinogenesis have been reported, few mouse lines enable gene manipulation selectively in the stomach. Here we established a Tff1-Cre bacterial artificial chromosome transgenic mouse line in an attempt to induce gene modification specifically in the gastric pit lineage. In the stomach, Tff1-Cre-mediated recombination was most evident in the pit lineage in the corpus and in entire antral glands; recombination was also observed in a few gastric chief and parietal cells. Outside the stomach, recombination was patchy throughout the intestines, and particularly frequently in the duodenum (Brunner glands), cecum, and proximal colon. In the stomachs of Tff1-Cre;LSL-KrasG12D mice, proliferating cell clusters expanded throughout the corpus glands, with foveolar cell expansion with ectopic Alcian blue-positive mucins, oxyntic atrophy, and pseudopyloric changes with spasmolytic polypeptide-expressing metaplasia; however, gastric cancer was not observed even at 12 months of age. Corpus-derived organoids from Tff1-Cre;LSL-KrasG12D mice exhibited accelerated growth and abnormal differentiation with a loss of chief and parietal cell markers. Tff1-Cre;Ptenflox/flox mice displayed similar changes to those seen in Tff1-Cre;LSL-KrasG12D mice, both with aberrant ERK activation within 3 months. In contrast, Tff1-Cre;Cdh1flox/flox mice initially showed signet ring-like cells that were rapidly lost with disruption of the mucosal surface, and later developed gastric epithelial shedding with hyperproliferation and loss of normal gastric lineages. Eventually, the glandular epithelium in Tff1-Cre;Cdh1flox/flox mice was completely replaced by squamous epithelium which expanded from the forestomach. Tff1-Cre mice offer an additional useful tool for studying gastric carcinogenesis both in vivo and in vitro. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Subject(s)
Cadherins/deficiency , Cell Proliferation , Cell Transformation, Neoplastic/metabolism , Gastric Mucosa/enzymology , Gastritis/enzymology , PTEN Phosphohydrolase/deficiency , Proto-Oncogene Proteins p21(ras)/metabolism , Stomach Neoplasms/enzymology , Animals , Cadherins/genetics , Cell Lineage , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Chromosomes, Artificial, Bacterial , Gastric Mucins/genetics , Gastric Mucins/metabolism , Gastric Mucosa/pathology , Gastritis/genetics , Gastritis/pathology , Gene Deletion , Gene Expression Regulation, Neoplastic , Integrases/genetics , Metaplasia , Mice, Transgenic , PTEN Phosphohydrolase/genetics , Phenotype , Proto-Oncogene Proteins p21(ras)/genetics , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Tissue Culture Techniques , Trefoil Factor-1/genetics
7.
Gastroenterology ; 154(1): 140-153.e17, 2018 01.
Article in English | MEDLINE | ID: mdl-28912017

ABSTRACT

BACKGROUND & AIMS: Chronic gastrointestinal inflammation increases the risk of cancer by mechanisms that are not well understood. Indoleamine-2,3-dioxygenase 1 (IDO1) is a heme-binding enzyme that regulates the immune response via catabolization and regulation of tryptophan availability for immune cell uptake. IDO1 expression is increased during the transition from chronic inflammation to gastric metaplasia. We investigated whether IDO1 contributes to the inflammatory response that mediates loss of parietal cells leading to metaplasia. METHODS: Chronic gastric inflammation was induced in Ido1-/- and CB57BL/6 (control) mice by gavage with Helicobacter felis or overexpression of interferon gamma in gastric parietal cells. We also performed studies in Jh-/- mice, which are devoid of B cells. Gastric tissues were collected and analyzed by flow cytometry, immunostaining, and real-time quantitative polymerase chain reaction. Plasma samples were analyzed by enzyme-linked immunosorbent assay. Gastric tissues were obtained from 20 patients with gastric metaplasia and 20 patients without gastric metaplasia (controls) and analyzed by real-time quantitative polymerase chain reaction; gastric tissue arrays were analyzed by immunohistochemistry. We collected genetic information on gastric cancers from The Cancer Genome Atlas database. RESULTS: H felis gavage induced significantly lower levels of pseudopyloric metaplasia in Ido1-/- mice, which had lower frequencies of gastric B cells, than in control mice. Blood plasma from H felis-infected control mice had increased levels of autoantibodies against parietal cells, compared to uninfected control mice, but this increase was lower in Ido1-/- mice. Chronically inflamed stomachs of Ido1-/- mice had significantly lower frequencies of natural killer cells in contact with parietal cells, compared with stomachs of control mice. Jh-/- mice had lower levels of pseudopyloric metaplasia than control mice in response to H felis infection. Human gastric pre-neoplasia and carcinoma specimens had increased levels of IDO1 messenger RNA compared with control gastric tissues, and IDO1 protein colocalized with B cells. Co-clustering of IDO1 messenger RNA with B-cell markers was corroborated by The Cancer Genome Atlas database. CONCLUSIONS: IDO1 mediates gastric metaplasia by regulating the B-cell compartment. This process appears to be associated with type II hypersensitivity/autoimmunity. The role of autoimmunity in the progression of pseudopyloric metaplasia warrants further investigation.


Subject(s)
Gastritis/etiology , Hypersensitivity/etiology , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Precancerous Conditions/enzymology , Stomach Neoplasms/etiology , Animals , B-Lymphocytes/physiology , Gastritis/enzymology , Gastritis/pathology , Humans , Hypersensitivity/enzymology , Hypersensitivity/pathology , Metaplasia , Mice , Mice, Inbred C57BL , Precancerous Conditions/pathology , Stomach Neoplasms/enzymology , Stomach Neoplasms/pathology
8.
J Coll Physicians Surg Pak ; 27(11): 678-681, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29132476

ABSTRACT

OBJECTIVE: To assess whether helicobacter pylori was associated with CDX2 expression in intestinal metaplasia, atrophic gastritis, dysplasia and gastric cancer. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Department of Pathology, The First Hospital of Jilin University, Changchun, China, from August 2016 to January 2017. METHODOLOGY: CDX2 expression was evaluated in 62 gastric antral biopsies; including 32 cases of intestinal metaplasia (IM) and 10 cases each of atrophic gastritis (AG), dysplasia and gastric cancer. Hematoxylin and Eosin staining was used to detect H.pyloriand immunohistochemistry was performed to observe CDX2 in the samples. RESULTS: Of the 62 patients inducted in the study, CDX2 expression was observed in 53 (85.5%). Mean age of these patients was 59 years (s.d.:11.3; range: 38-87) and included 32 males (60.38%) and 21 females (39.62%). However, age and gender were not found to be significantly associated with expression of CDX2 (p >0.05). CDX2 was very frequently expressed in individuals with IM (90.6%). Most of the patients with IM were males (17/29) as compared to females (12/29). However, the difference was not statistically significant (p=0.568). Only 4 out of 29 IM CDX2 positive specimens tested positive for H.pylori(p=1.0). CONCLUSION: CDX2 is highly expressed along the atrophic gastritis-metaplasia-dysplasia-cancer sequential. Though CDX2 expression is quite dominant in IM, but its expression is not associated with H.pyloriinfection.


Subject(s)
CDX2 Transcription Factor/metabolism , Gastric Mucosa/microbiology , Gastritis/microbiology , Helicobacter Infections/microbiology , Helicobacter pylori/pathogenicity , Homeodomain Proteins/metabolism , Intestines/pathology , Metaplasia/metabolism , Adult , Aged , Aged, 80 and over , Biopsy , Endoscopy , Female , Gastric Mucosa/enzymology , Gastric Mucosa/pathology , Gastritis/enzymology , Gastritis/pathology , Helicobacter Infections/complications , Helicobacter Infections/enzymology , Helicobacter Infections/pathology , Humans , Intestinal Mucosa/metabolism , Male , Metaplasia/microbiology , Metaplasia/pathology , Middle Aged , Precancerous Conditions/pathology
9.
Pharm Biol ; 55(1): 2110-2115, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28874080

ABSTRACT

CONTEXT: Aloe has been used for the prevention and cure of various diseases and symptoms including burns, injuries, oedema and pain. OBJECTIVE: This study determines the specific inhibitory activity of matrix metalloproteinase (MMP)-9 induced by the low molecular-weight gel fraction of Aloe vera (L.) Burm.f. (lgfAv) on alcohol-induced acute gastric lesions. MATERIALS AND METHODS: We examined the protective effects of oral (p.o.) administration of lgfAv (molecular weight cutoff <50.0 kDa, 150.0 mg/kg body weight) in a Balb/c mouse model of alcohol-induced acute gastritis for 1 h exposure. By measuring ulcer index, we compared the antiulcerative activity of the fraction. mRNA expression and immunohistochemical analysis of various biomarkers were performed. RESULTS: The lgfAv-treated mice exhibited drastically fewer ulcer lesions than the untreated control mice did. It featured that lgfAv lessened the ulcer lesions than their relevant controls. Moreover, the transcriptional level of MMP-9 was completely alleviated by lgfAv treatment in alcohol-treated gastritis-induced mice. DISCUSSION: The transcriptional level of MMP-9 was significantly alleviated by lgfAv treatment of the model. However, reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry experiments revealed that lgfAv treatment in mucosal tissues had the potential to inhibit the mRNA and protein expression levels of MMP-9, respectively. The protein expression of MMP-9 was closely associated with lgfAv-induced gastroprotection against alcohol-induced gastric lesions. CONCLUSIONS: The present findings suggest that lgfAv has the potential to alleviate alcohol-induced acute gastric lesions, which is mediated in part, mainly by the suppression of the mRNA expression of MMP-9.


Subject(s)
Aloe , Ethanol/toxicity , Matrix Metalloproteinase 9/biosynthesis , Plant Extracts/therapeutic use , Stomach Ulcer/chemically induced , Stomach Ulcer/prevention & control , Animals , Enzyme Induction/drug effects , Enzyme Induction/physiology , Gastric Mucosa/drug effects , Gastric Mucosa/enzymology , Gastritis/chemically induced , Gastritis/enzymology , Gastritis/prevention & control , Gels , Male , Mice , Mice, Inbred BALB C , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Stomach Ulcer/enzymology
10.
Oxid Med Cell Longev ; 2017: 1320241, 2017.
Article in English | MEDLINE | ID: mdl-28744336

ABSTRACT

Switching of cellular energy production from oxidative phosphorylation (OXPHOS) by mitochondria to aerobic glycolysis occurs in many types of tumors. However, the significance of this switching for the development of gastric carcinoma and what connection it may have to Helicobacter pylori infection of the gut, a primary cause of gastric cancer, are poorly understood. Therefore, we investigated the expression of OXPHOS complexes in two types of human gastric carcinomas ("intestinal" and "diffuse"), bacterial gastritis with and without metaplasia, and chemically induced gastritis by using immunohistochemistry. Furthermore, we analyzed the effect of HP infection on several key mitochondrial proteins. Complex I expression was significantly reduced in intestinal type (but not diffuse) gastric carcinomas compared to adjacent control tissue, and the reduction was independent of HP infection. Significantly, higher complex I and complex II expression was present in large tumors. Furthermore, higher complex II and complex III protein levels were also obvious in grade 3 versus grade 2. No differences of OXPHOS complexes and markers of mitochondrial biogenesis were found between bacterially caused and chemically induced gastritis. Thus, intestinal gastric carcinomas, but not precancerous stages, are frequently characterized by loss of complex I, and this pathophysiology occurs independently of HP infection.


Subject(s)
Electron Transport Complex I/biosynthesis , Gastritis/enzymology , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Helicobacter Infections/enzymology , Helicobacter pylori , Neoplasm Proteins/biosynthesis , Oxidative Phosphorylation , Stomach Neoplasms/enzymology , Female , Gastritis/pathology , Helicobacter Infections/pathology , Humans , Male , Stomach Neoplasms/pathology
11.
Infect Genet Evol ; 53: 167-174, 2017 09.
Article in English | MEDLINE | ID: mdl-28577915

ABSTRACT

Helicobacter pylori infect millions of people around the world. It occupies a niche in the human gastrointestinal tract characterized by high expression of a repertoire of carbohydrates. ABO and Lewis histo-blood group systems are controlled by genes coding for functional glycosyltransferases which synthesize great diversity of related fucosylated carbohydrate in different tissues, including gastrointestinal mucosa, and exocrine secretions. The structural diversity of histo-blood group carbohydrates is highly complex and depends on epistatic interactions among gene-encoding glycosyltransferases. The histo-blood group glycosyltransferases act in the glycosylation of proteins and lipids in the human gastrointestinal tract allowing the expression of a variety of potential receptors in which H. pylori can adhere. These oligosaccharide molecules are part of the gastrointestinal repertoire of carbohydrates which act as potential receptors for microorganisms, including H. pylori. This Gram-negative bacillus is one of the main causes of the gastrointestinal diseases such as chronic active gastritis, peptic ulcer, and cancer of stomach. Previous reports showed that some H. pylori strains use carbohydrates as receptors to adhere to the gastric and duodenal mucosa. Since some histo-blood group carbohydrates are highly expressed in one but not in others histo-blood group phenotypes it has pointed out that quantitative differences among them influence the susceptibility to diseases caused by H. pylori. Additionally, some experiments using animal model are helping us to understand how this bacillus explore histo-blood group carbohydrates as potential receptors, offering possibility to explore new strategies of management of infection, disease treatment, and prevention. This text highlights the importance of structural diversity of ABO and Lewis histo-blood group carbohydrates as facilitators for H. pylori infection.


Subject(s)
ABO Blood-Group System/metabolism , Carbohydrates/chemistry , Epistasis, Genetic , Helicobacter Infections/genetics , Helicobacter pylori/genetics , Lewis Blood Group Antigens/metabolism , ABO Blood-Group System/chemistry , ABO Blood-Group System/genetics , Animals , Carbohydrate Sequence , Gastritis/enzymology , Gastritis/genetics , Gastritis/microbiology , Gastritis/pathology , Glycosylation , Glycosyltransferases/genetics , Glycosyltransferases/metabolism , Helicobacter Infections/enzymology , Helicobacter Infections/microbiology , Helicobacter Infections/pathology , Helicobacter pylori/growth & development , Helicobacter pylori/metabolism , Host-Pathogen Interactions , Humans , Lewis Blood Group Antigens/chemistry , Lewis Blood Group Antigens/genetics , Peptic Ulcer/enzymology , Peptic Ulcer/genetics , Peptic Ulcer/microbiology , Peptic Ulcer/pathology , Stomach Neoplasms/enzymology , Stomach Neoplasms/genetics , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology
12.
Biomed Pharmacother ; 91: 338-349, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28463797

ABSTRACT

Gastritis is preponderantly characterized by inflammation of the lining epithelial layer and the chronic gastritis is considered as a pre-cancer lesion. For many centuries olive (Olea europaea) leaf has been used for its putative health potential, nonetheless, to date, the gastroprotective effects of olive leaves have not been studied yet. Hence, in this study we investigated whether olive leaf extract (OLE) could protect gastric mucosa against HCl/ethanol-induced gastric mucosal damage in rats. Hcl/ethanol administration caused significant damage to the gastric mucosa, as confirmed by gastric ulcer index and histological evaluation. However, this damage was largely prevented by pre-administering 20mg/kg omeprazole or 100mg/kg OLE. Interestingly, the damage was completely prevented by pre-administering 200 and 300mg/kg OLE. Moreover, OLE attenuated the inflammatory response by decreasing nuclear factor-κB (NF-κB), cycloxygenase-2 (COX-2) and tumor necrosis factor-α (TNF-α) expressions, and down-regulating inducible nitric oxide synthase (iNOS) and interleukin-1ß (IL-1ß) in gastric mucosa. The gastroprotective mechanism of OLE involved the promotion of enzymatic and nonenzymatic molecules (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione reduced form), promoting nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression, halting lipid peroxidation and preventing the overproduction of nitric oxide. Together, our findings clearly demonstrated that OLE could prevent HCl/ethanol-induced gastritis by attenuating inflammation and oxidant/antioxidant imbalance. Indeed, OLE could potentially be useful as a natural therapy for gastritis.


Subject(s)
Antioxidants/metabolism , Gastritis/drug therapy , Gastritis/enzymology , Inflammation/drug therapy , Methanol/chemistry , Olea/chemistry , Plant Extracts/therapeutic use , Plant Leaves/chemistry , Animals , Body Weight/drug effects , Chromatography, High Pressure Liquid , Ethanol , Gastritis/chemically induced , Gastritis/pathology , Hydrochloric Acid , Inflammation/pathology , Male , Oxidative Stress/drug effects , Rats, Wistar , Stomach Ulcer/chemically induced , Stomach Ulcer/drug therapy , Stomach Ulcer/pathology , Toxicity Tests, Acute
13.
J Ethnopharmacol ; 190: 251-60, 2016 Aug 22.
Article in English | MEDLINE | ID: mdl-27286918

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Xanthium strumarium L. (Asteraceae) has traditionally been used to treat bacterial infections, nasal sinusitis, urticaria, arthritis, chronic bronchitis and rhinitis, allergic rhinitis, edema, lumbago, and other ailments. However, the molecular mechanisms by which this plant exerts its anti-inflammatory effects are poorly characterized. Here we studied the immunopharmacological activities of the methanolic extract of the aerial parts of this plant (Xs-ME) and validated its pharmacological targets. MATERIALS AND METHODS: To evaluate the anti-inflammatory activity of Xs-ME, we employed lipopolysaccharide (LPS)-treated macrophages and an HCl/EtOH-induced mouse model of gastritis. We also used HPLC to identify the potentially active anti-inflammatory components of this extract. The molecular mechanisms of its anti-inflammatory activity were studied by kinase assays, reporter gene assays, immunoprecipitation analysis, and overexpression of target enzymes. RESULTS: The production of nitric oxide (NO) and prostaglandin E2 (PGE2) were both suppressed by Xs-ME. Moreover, orally administered Xs-ME ameliorated HCl/EtOH-induced gastric lesions. Furthermore, this extract downregulated the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 and reduced the nuclear levels of NF-κB. Signaling events upstream of NF-κB translocation, such as phosphorylation of AKT and the formation of PDK1-AKT signaling complexes, were also inhibited by Xs-ME. Moreover, Xs-ME suppressed the enzymatic activity of PDK1. Additionally, PDK1-induced luciferase activity and Akt phosphorylation were both inhibited by Xs-ME. We also identified the polyphenol resveratrol as a likely active anti-inflammatory component in Xs-ME that targets PDK1. CONCLUSION: Xs-ME exerts anti-inflammatory activity in vitro and in vivo by inhibiting PDK1 kinase activity and blocking signaling to its downstream transcription factor, NF-κB.


Subject(s)
3-Phosphoinositide-Dependent Protein Kinases/antagonists & inhibitors , Anti-Inflammatory Agents/pharmacology , Gastritis/prevention & control , Macrophages/drug effects , Methanol/chemistry , NF-kappa B/metabolism , Plant Extracts/pharmacology , Protein Kinase Inhibitors/pharmacology , Signal Transduction/drug effects , Solvents/chemistry , Xanthium/chemistry , 3-Phosphoinositide-Dependent Protein Kinases/genetics , 3-Phosphoinositide-Dependent Protein Kinases/metabolism , Animals , Anti-Inflammatory Agents/isolation & purification , Cyclooxygenase 2/metabolism , Dinoprostone/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Ethanol , Gastritis/chemically induced , Gastritis/enzymology , Gastritis/genetics , HEK293 Cells , Humans , Hydrochloric Acid , Inflammation Mediators/metabolism , Lipopolysaccharides/pharmacology , Macrophages/enzymology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , NF-kappa B/genetics , Nitric Oxide/metabolism , Nitric Oxide Synthase Type II/metabolism , Phosphorylation , Phytotherapy , Plant Components, Aerial/chemistry , Plant Extracts/isolation & purification , Plants, Medicinal , Proto-Oncogene Proteins c-akt/metabolism , RAW 264.7 Cells , Time Factors , Transfection
14.
Am J Vet Res ; 77(7): 721-9, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27347825

ABSTRACT

OBJECTIVE To compare expression, activity, and fecal concentration of intestinal alkaline phosphatase (IAP) between healthy dogs and dogs with chronic enteropathy (CE). ANIMALS 9 healthy university-owned Beagles and 109 healthy client-owned dogs (controls) and 28 dogs with CE (cases). PROCEDURES Cases were defined as dogs with persistent (> 3 weeks) gastrointestinal signs that failed to respond to antimicrobials and anti-inflammatory doses of prednisolone or dietary trials, did not have mechanical gastrointestinal abnormalities as determined by abdominal radiography and ultrasonography, and had a diagnosis of lymphoplasmacytic enteritis or eosinophilic gastroenteritis on histologic examination of biopsy specimens. Duodenal and colonic mucosa biopsy specimens were obtained from the 9 university-owned Beagles and all cases for histologic examination and determination of IAP expression (by real-time quantitative PCR assay) and activity (by enzyme histochemical analysis). Fecal samples were obtained from all dogs for determination of fecal IAP concentration by a quantitative enzyme reaction assay. RESULTS For dogs evaluated, IAP expression and activity were localized at the luminal side of epithelial cells in the mucosa and intestinal crypts, although both were greater in the duodenum than in the colon. Active IAP was detected in the feces of all dogs. Intestinal alkaline phosphatase expression and activity were lower for cases than for controls, and fecal IAP concentration for dogs with moderate and severe CE was lower than that for dogs with mild CE. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs with CE had impaired IAP expression and activity. Additional research is necessary to elucidate the role of IAP in the pathogenesis of CE.


Subject(s)
Alkaline Phosphatase/metabolism , Dog Diseases/enzymology , Enteritis/veterinary , Eosinophilia/veterinary , Gastritis/veterinary , Alkaline Phosphatase/biosynthesis , Animals , Colon/enzymology , Colon/pathology , Dog Diseases/pathology , Dogs , Duodenum/enzymology , Duodenum/pathology , Enteritis/enzymology , Enteritis/pathology , Eosinophilia/enzymology , Eosinophilia/pathology , Feces/enzymology , Female , Gastritis/enzymology , Gastritis/pathology , Male , Real-Time Polymerase Chain Reaction
15.
Gut Liver ; 10(5): 749-56, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27172930

ABSTRACT

BACKGROUND/AIMS: The aim of this study was to evaluate the effect of the synthetic S-allyl-L-cysteine (SAC) PMK-S005 on gastric acid secretion, inflammation, and antioxidant enzymes in aging rats. METHODS: The rats were divided into four groups at 31 weeks of age and were continuously fed a diet containing a vehicle control, PMK-S005 (5 or 10 mg/kg), or lansoprazole (5 mg/kg). Gastric acid secretion and connective tissue thickness of the lamina propria were evaluated at 74 weeks and 2 years of age. Tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and COX-2 levels were measured by using enzyme-linked immunosorbent assays (ELISAs) or Western blot assays. Levels of antioxidant enzymes, including heme oxyganase 1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO-1), were also measured. RESULTS: As the rats aged, gastric acid secretion significantly decreased, and the connective tissue of the lamina propria increased. However, 74-week-old rats in the PMK-S005 group exhibited greater levels of gastric acid secretion than those of the control and lansoprazole groups. The increase of TNF-α, IL-1ß, and COX- 2 expression in 74-week and 2-year-old control rats were inhibited by PMK-S005. In addition, the decrease in HO-1 and NQO-1 protein expression that occurred with aging was inhibited by PMK-S005 in the 74-week-old rats. CONCLUSIONS: These results suggest that PMK-S005 has therapeutic potential as an antiaging agent to ameliorate age-related gastric acid secretion, inflammation, and oxidative stress in the stomach.


Subject(s)
Aging/drug effects , Gastritis/drug therapy , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Stomach/drug effects , Animals , Antioxidants/analysis , Cyclooxygenase 2/analysis , Enzyme-Linked Immunosorbent Assay , Gastric Acid/metabolism , Gastric Mucosa/metabolism , Gastritis/enzymology , Interleukin-1beta/analysis , Male , Rats , Rats, Inbred F344 , Stomach/enzymology , Tumor Necrosis Factor-alpha/analysis
16.
World J Microbiol Biotechnol ; 32(6): 92, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27116958

ABSTRACT

UNLABELLED: We aimed to study MLH1 and MGMT methylation status in Helicobacter pylori-associated chronic gastritis in Egyptian patients with and without gastric cancer. 39 patients were included in our study. They were divided into 2 groups; patients without (group I) and with gastric adenocarcinoma (group II). Patients were subjected to clinical examination, abdominal ultrasound and upper endoscopy for gastric biopsy. Biopsies were subjected to urease test, histological examination, and DNA purification. H. pylori, Braf, Kras, MLH1 and MGMT methylation were assessed by quantitative PCR. DNA sequencing was performed to assess Braf and Kras genes mutation. qPCR of H. pylori was significantly higher in patients with adenocarcinoma (group II) than those without adenocarcinoma (group I); with a p < 0.001 as well as in patients with age above 50 years with a p value = 0.008. By applying logistic regression analysis it was reported that the H. pylori qPCR is a significant predictor to the adenocarcinoma with OR = 1.025 (95 % CI: 1. 002-1.048), with sensitivity of 90 % and specificity of 100 %. Adenocarcinoma patients had a significantly higher mean age and levels of H. Pylori, Braf, K-ras, methylated MGMT and methylated MLH1 than those of gastritis patients. DNA sequence analysis of Braf (codon 12) and Kras (codon 600) had genes mutation in gastric adenocarcinoma versus chronic gastritis. CONCLUSION: H. pylori may cause epigenetic changes predisposing the patients to cancer stomach. Estimation of H. pylori by qPCR can be a good predictor to adenocarcinoma. Braf and Kras genes mutation were reveled in gastritis and adenocarcinoma patients.


Subject(s)
Gastritis/genetics , Helicobacter Infections/genetics , Helicobacter pylori/genetics , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Adenocarcinoma/genetics , Adenocarcinoma/microbiology , Adult , Aged , Chronic Disease , DNA Methylation , DNA Modification Methylases/genetics , DNA Repair Enzymes/genetics , Egypt , Epigenesis, Genetic , Female , Gastritis/enzymology , Gastritis/microbiology , Gastritis/pathology , Gene Expression Profiling , Helicobacter Infections/diagnosis , Helicobacter Infections/enzymology , Helicobacter Infections/microbiology , Humans , Male , Middle Aged , MutL Protein Homolog 1/genetics , Mutation , Stomach Neoplasms/enzymology , Stomach Neoplasms/genetics , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology , Tumor Suppressor Proteins/genetics
17.
APMIS ; 124(4): 252-6, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26765960

ABSTRACT

Human gastric diseases have shown significant changes in the activity and expression of superoxide dismutase (SOD) isoforms. The aim of this study was to detect Mn-SOD activity and expression in the tissue of gastric mucosa, primarily in chronic gastritis (immunohistochemical Helicobacter pylori-negative gastritis, without other pathohistological changes) and to evaluate their possible connection with pathohistological diagnosis. We examined 51 consecutive outpatients undergoing endoscopy for upper gastrointestinal symptoms. Patients were classified based on their histopathological examinations and divided into three groups: 51 patients (archive samples between 2004-2009) with chronic immunohistochemical Helicobacter pylori-negative gastritis (mononuclear cells infiltration were graded as absent, moderate, severe) divided into three groups. Severity of gastritis was graded according to the updated Sydney system. Gastric tissue samples were used to determine the expression of Mn-SOD with anti-Mn-SOD Ab immunohistochemically. The Mn-SOD expression was more frequently present in specimens with severe and moderate inflammation of gastric mucosa than in those with normal mucosa. In patients with normal histological finding, positive immunoreactivity of Mn-SOD was not found. Our results determine the changes in Mn-SOD expression occurring in the normal gastric mucosa that had undergone changes in the intensity of chronic inflammatory infiltrates in the lamina propria.


Subject(s)
Gastric Mucosa/enzymology , Gastritis/diagnosis , Gastritis/enzymology , Superoxide Dismutase/genetics , Antibodies/chemistry , Case-Control Studies , Chronic Disease , Gastric Mucosa/pathology , Gastritis/genetics , Gastritis/pathology , Gastroscopy , Gene Expression , Humans , Immunohistochemistry , Outpatients , Severity of Illness Index , Superoxide Dismutase/metabolism
18.
J Immunol Res ; 2014: 762514, 2014.
Article in English | MEDLINE | ID: mdl-25309933

ABSTRACT

Helicobacter pylori is one of the most common causes of chronic gastritis. With the development of the disease cellular inflammatory infiltrates composed of lymphocytes, plasma cells, and macrophages are formed in epithelium and lamina propria of the stomach. These cells are capable of secreting a number of active substances, including inducible nitric oxide synthase (iNOS). We examined the relationship between H. pylori and secretion of iNOS by cells of inflammatory infiltrates in chronic gastritis by light microscopy and immunohistochemistry. The data obtained indicate that stimulation of H. pylori immune system cells of the host organism during development of chronic gastritis causes increase in number of macrophages and lymphocytes in the inflammatory infiltrate of the gastric mucosa. This is accompanied with increased expression of inducible NO-synthase with excess free radicals in the tissues, which leads to secondary alterations and exacerbates the inflammation with impaired regeneration processes.


Subject(s)
Gastric Mucosa/immunology , Gastritis/immunology , Helicobacter Infections/immunology , Helicobacter pylori/immunology , Lymphocytes/immunology , Macrophages/immunology , Nitric Oxide Synthase Type II/immunology , Cell Count , Chronic Disease , Gastric Mucosa/enzymology , Gastric Mucosa/microbiology , Gastritis/enzymology , Gastritis/microbiology , Helicobacter Infections/enzymology , Helicobacter Infections/microbiology , Helicobacter pylori/physiology , Host-Pathogen Interactions/immunology , Humans , Immunohistochemistry , Lymphocytes/enzymology , Lymphocytes/microbiology , Macrophages/enzymology , Macrophages/microbiology , Middle Aged , Nitric Oxide Synthase Type II/metabolism
20.
Indian J Gastroenterol ; 33(4): 330-5, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24610583

ABSTRACT

OBJECTIVES: This study was done in order to investigate the effect of CYP2C19 genetic polymorphism on the cure rate of children who received proton pump inhibitors (PPI)-based triple therapy for treating Helicobacter pylori (H. pylori) infection. METHODS: Participants included 100 children with H. pylori-positive gastritis diagnosed by endoscopy and biopsy in addition to H. pylori stool antigen test. Cure rate was assessed after 1 month of completion of a triple treatment course for 14 days. CYP2C19 polymorphism was analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: Results showed that cases with a CYP2C19 genotypic status consistent with the heterozygote extensive metabolizers (HetEMs) had a higher cure rate of H. pylori when compared with the homozygote extensive metabolizers (HomEMs) although it was statistically nonsignificant (84.6 vs. 69.2). In addition, the poor metabolizers (PMs) had a higher cure rate compared with those of the HomEMs which was also statistically nonsignificant (77.8 vs. 69.2). The cure rate was also higher among both the groups of HetEMs and PMs combined together compared to the HomEMs (OR = 2.15, p > 0.05). Comparing cases regarding their age, gender, and severity of H. pylori gastritis revealed a better cure rate in the age group >10 years, in females and in mild and moderate cases than other cases although statistically nonsignificant. CONCLUSION: The higher cure rate of H. pylori infection using the triple therapy for 2 weeks among HetEMs and PMs cases compared to the HomEMs might warrant a need for a therapy augmentation or modification for the HomEMs.


Subject(s)
Cytochrome P-450 CYP2C19/genetics , Gastritis/drug therapy , Gastritis/microbiology , Helicobacter Infections , Helicobacter pylori , Polymorphism, Genetic , Amoxicillin/administration & dosage , Child , Clarithromycin/administration & dosage , Female , Gastritis/enzymology , Gastritis/genetics , Humans , Lansoprazole/administration & dosage , Male , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Proton Pump Inhibitors/administration & dosage , Severity of Illness Index , Treatment Outcome
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