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1.
Int Immunopharmacol ; 90: 107213, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33296781

RESUMEN

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.


Asunto(s)
Antiinflamatorios/farmacología , Mucosa Gástrica/efectos de los fármacos , Gastritis/prevención & control , Glucósidos Iridoides/farmacología , Metaloproteinasa 10 de la Matriz/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Etanol , Femenino , Mucosa Gástrica/enzimología , Mucosa Gástrica/patología , Gastritis/inducido químicamente , Gastritis/enzimología , Gastritis/patología , Humanos , Mediadores de Inflamación/metabolismo , Metaloproteinasa 10 de la Matriz/genética , Ratones Endogámicos C57BL , Fosforilación , Transducción de Señal
3.
Oncogene ; 39(22): 4465-4474, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32350444

RESUMEN

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.


Asunto(s)
Adenocarcinoma/etiología , Daño del ADN , Gastritis/enzimología , Infecciones por Helicobacter/enzimología , Helicobacter pylori/patogenicidad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/fisiología , Espermina/metabolismo , Neoplasias Gástricas/etiología , Adenocarcinoma/microbiología , Animales , Transformación Celular Neoplásica , Gastritis/genética , Gastritis/microbiología , Gastritis/patología , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Organoides , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/deficiencia , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Proteoma , ARN Mensajero/biosíntesis , Transducción de Señal , Espermidina/biosíntesis , Neoplasias Gástricas/microbiología , beta Catenina/fisiología , Poliamino Oxidasa
4.
DNA Repair (Amst) ; 89: 102836, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32143126

RESUMEN

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.


Asunto(s)
Proteínas de Unión al ADN/genética , Endonucleasas/genética , Gastritis/genética , Infecciones por Helicobacter/complicaciones , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto/genética , Neoplasias Gástricas/genética , Adulto , Reparación de la Incompatibilidad de ADN , Reparación del ADN , Femenino , Gastritis/enzimología , Gastritis/etiología , Gastritis/microbiología , Regulación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Helicobacter pylori , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/etiología , Neoplasias Gástricas/microbiología
5.
Am J Physiol Gastrointest Liver Physiol ; 318(5): G931-G945, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32174134

RESUMEN

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.


Asunto(s)
Retículo Endoplásmico/enzimología , Células Epiteliales/enzimología , Mucosa Gástrica/enzimología , Gastritis/enzimología , Proteínas de Choque Térmico/metabolismo , Infecciones por Helicobacter/enzimología , Helicobacter pylori/patogenicidad , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Células Cultivadas , Retículo Endoplásmico/microbiología , Chaperón BiP del Retículo Endoplásmico , Estabilidad de Enzimas , Células Epiteliales/microbiología , Mucosa Gástrica/microbiología , Gastritis/genética , Gastritis/microbiología , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/microbiología , Interacciones Huésped-Patógeno , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Pliegue de Proteína , Proteolisis , ATPasa Intercambiadora de Sodio-Potasio/genética , Ubiquitinación
6.
J Pathol ; 247(1): 35-47, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30168144

RESUMEN

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.


Asunto(s)
Cadherinas/deficiencia , Proliferación Celular , Transformación Celular Neoplásica/metabolismo , Mucosa Gástrica/enzimología , Gastritis/enzimología , Fosfohidrolasa PTEN/deficiencia , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Neoplasias Gástricas/enzimología , Animales , Cadherinas/genética , Linaje de la Célula , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Cromosomas Artificiales Bacterianos , Mucinas Gástricas/genética , Mucinas Gástricas/metabolismo , Mucosa Gástrica/patología , Gastritis/genética , Gastritis/patología , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Integrasas/genética , Metaplasia , Ratones Transgénicos , Fosfohidrolasa PTEN/genética , Fenotipo , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Técnicas de Cultivo de Tejidos , Factor Trefoil-1/genética
7.
Gastroenterology ; 154(1): 140-153.e17, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28912017

RESUMEN

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.


Asunto(s)
Gastritis/etiología , Hipersensibilidad/etiología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Lesiones Precancerosas/enzimología , Neoplasias Gástricas/etiología , Animales , Linfocitos B/fisiología , Gastritis/enzimología , Gastritis/patología , Humanos , Hipersensibilidad/enzimología , Hipersensibilidad/patología , Metaplasia , Ratones , Ratones Endogámicos C57BL , Lesiones Precancerosas/patología , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/patología
8.
J Coll Physicians Surg Pak ; 27(11): 678-681, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29132476

RESUMEN

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.


Asunto(s)
Factor de Transcripción CDX2/metabolismo , Mucosa Gástrica/microbiología , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/patogenicidad , Proteínas de Homeodominio/metabolismo , Intestinos/patología , Metaplasia/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Endoscopía , Femenino , Mucosa Gástrica/enzimología , Mucosa Gástrica/patología , Gastritis/enzimología , Gastritis/patología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/enzimología , Infecciones por Helicobacter/patología , Humanos , Mucosa Intestinal/metabolismo , Masculino , Metaplasia/microbiología , Metaplasia/patología , Persona de Mediana Edad , Lesiones Precancerosas/patología
9.
Pharm Biol ; 55(1): 2110-2115, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28874080

RESUMEN

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.


Asunto(s)
Aloe , Etanol/toxicidad , Metaloproteinasa 9 de la Matriz/biosíntesis , Extractos Vegetales/uso terapéutico , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/prevención & control , Animales , Inducción Enzimática/efectos de los fármacos , Inducción Enzimática/fisiología , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/enzimología , Gastritis/inducido químicamente , Gastritis/enzimología , Gastritis/prevención & control , Geles , Masculino , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Úlcera Gástrica/enzimología
10.
Oxid Med Cell Longev ; 2017: 1320241, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28744336

RESUMEN

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.


Asunto(s)
Complejo I de Transporte de Electrón/biosíntesis , Gastritis/enzimología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Infecciones por Helicobacter/enzimología , Helicobacter pylori , Proteínas de Neoplasias/biosíntesis , Fosforilación Oxidativa , Neoplasias Gástricas/enzimología , Femenino , Gastritis/patología , Infecciones por Helicobacter/patología , Humanos , Masculino , Neoplasias Gástricas/patología
11.
Infect Genet Evol ; 53: 167-174, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28577915

RESUMEN

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.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/metabolismo , Carbohidratos/química , Epistasis Genética , Infecciones por Helicobacter/genética , Helicobacter pylori/genética , Antígenos del Grupo Sanguíneo de Lewis/metabolismo , Sistema del Grupo Sanguíneo ABO/química , Sistema del Grupo Sanguíneo ABO/genética , Animales , Secuencia de Carbohidratos , Gastritis/enzimología , Gastritis/genética , Gastritis/microbiología , Gastritis/patología , Glicosilación , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Infecciones por Helicobacter/enzimología , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/crecimiento & desarrollo , Helicobacter pylori/metabolismo , Interacciones Huésped-Patógeno , Humanos , Antígenos del Grupo Sanguíneo de Lewis/química , Antígenos del Grupo Sanguíneo de Lewis/genética , Úlcera Péptica/enzimología , Úlcera Péptica/genética , Úlcera Péptica/microbiología , Úlcera Péptica/patología , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología
12.
Biomed Pharmacother ; 91: 338-349, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28463797

RESUMEN

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.


Asunto(s)
Antioxidantes/metabolismo , Gastritis/tratamiento farmacológico , Gastritis/enzimología , Inflamación/tratamiento farmacológico , Metanol/química , Olea/química , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Animales , Peso Corporal/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Etanol , Gastritis/inducido químicamente , Gastritis/patología , Ácido Clorhídrico , Inflamación/patología , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/patología , Pruebas de Toxicidad Aguda
13.
Am J Vet Res ; 77(7): 721-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27347825

RESUMEN

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.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Enfermedades de los Perros/enzimología , Enteritis/veterinaria , Eosinofilia/veterinaria , Gastritis/veterinaria , Fosfatasa Alcalina/biosíntesis , Animales , Colon/enzimología , Colon/patología , Enfermedades de los Perros/patología , Perros , Duodeno/enzimología , Duodeno/patología , Enteritis/enzimología , Enteritis/patología , Eosinofilia/enzimología , Eosinofilia/patología , Heces/enzimología , Femenino , Gastritis/enzimología , Gastritis/patología , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa
14.
J Ethnopharmacol ; 190: 251-60, 2016 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-27286918

RESUMEN

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.


Asunto(s)
Proteínas Quinasas Dependientes de 3-Fosfoinosítido/antagonistas & inhibidores , Antiinflamatorios/farmacología , Gastritis/prevención & control , Macrófagos/efectos de los fármacos , Metanol/química , FN-kappa B/metabolismo , Extractos Vegetales/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal/efectos de los fármacos , Solventes/química , Xanthium/química , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/genética , Proteínas Quinasas Dependientes de 3-Fosfoinosítido/metabolismo , Animales , Antiinflamatorios/aislamiento & purificación , Ciclooxigenasa 2/metabolismo , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Etanol , Gastritis/inducido químicamente , Gastritis/enzimología , Gastritis/genética , Células HEK293 , Humanos , Ácido Clorhídrico , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/enzimología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , FN-kappa B/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fosforilación , Fitoterapia , Componentes Aéreos de las Plantas/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células RAW 264.7 , Factores de Tiempo , Transfección
15.
Gut Liver ; 10(5): 749-56, 2016 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-27172930

RESUMEN

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.


Asunto(s)
Envejecimiento/efectos de los fármacos , Gastritis/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Estómago/efectos de los fármacos , Animales , Antioxidantes/análisis , Ciclooxigenasa 2/análisis , Ensayo de Inmunoadsorción Enzimática , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Gastritis/enzimología , Interleucina-1beta/análisis , Masculino , Ratas , Ratas Endogámicas F344 , Estómago/enzimología , Factor de Necrosis Tumoral alfa/análisis
16.
World J Microbiol Biotechnol ; 32(6): 92, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27116958

RESUMEN

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.


Asunto(s)
Gastritis/genética , Infecciones por Helicobacter/genética , Helicobacter pylori/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Adenocarcinoma/genética , Adenocarcinoma/microbiología , Adulto , Anciano , Enfermedad Crónica , Metilación de ADN , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Egipto , Epigénesis Genética , Femenino , Gastritis/enzimología , Gastritis/microbiología , Gastritis/patología , Perfilación de la Expresión Génica , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/enzimología , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Mutación , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Proteínas Supresoras de Tumor/genética
17.
APMIS ; 124(4): 252-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26765960

RESUMEN

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.


Asunto(s)
Mucosa Gástrica/enzimología , Gastritis/diagnóstico , Gastritis/enzimología , Superóxido Dismutasa/genética , Anticuerpos/química , Estudios de Casos y Controles , Enfermedad Crónica , Mucosa Gástrica/patología , Gastritis/genética , Gastritis/patología , Gastroscopía , Expresión Génica , Humanos , Inmunohistoquímica , Pacientes Ambulatorios , Índice de Severidad de la Enfermedad , Superóxido Dismutasa/metabolismo
18.
J Immunol Res ; 2014: 762514, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25309933

RESUMEN

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.


Asunto(s)
Mucosa Gástrica/inmunología , Gastritis/inmunología , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Linfocitos/inmunología , Macrófagos/inmunología , Óxido Nítrico Sintasa de Tipo II/inmunología , Recuento de Células , Enfermedad Crónica , Mucosa Gástrica/enzimología , Mucosa Gástrica/microbiología , Gastritis/enzimología , Gastritis/microbiología , Infecciones por Helicobacter/enzimología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/fisiología , Interacciones Huésped-Patógeno/inmunología , Humanos , Inmunohistoquímica , Linfocitos/enzimología , Linfocitos/microbiología , Macrófagos/enzimología , Macrófagos/microbiología , Persona de Mediana Edad , Óxido Nítrico Sintasa de Tipo II/metabolismo
20.
Indian J Gastroenterol ; 33(4): 330-5, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24610583

RESUMEN

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.


Asunto(s)
Citocromo P-450 CYP2C19/genética , Gastritis/tratamiento farmacológico , Gastritis/microbiología , Infecciones por Helicobacter , Helicobacter pylori , Polimorfismo Genético , Amoxicilina/administración & dosificación , Niño , Claritromicina/administración & dosificación , Femenino , Gastritis/enzimología , Gastritis/genética , Humanos , Lansoprazol/administración & dosificación , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Inhibidores de la Bomba de Protones/administración & dosificación , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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