Helicobacter pylori induces matrix metalloproteinase-9 through activation of nuclear factor kappaB

Argel's stemmoside C as a novel natural remedy for mice with alcohol-induced gastric ulcer based on its molecular mechanistic pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Solenostemma argel is widely distributed in Africa & Asia with traditional usage in alleviating abdominal colic, aches, & cramps. This plant is rich in phytochemicals, which must be explored for its pharmacological effects.

PURPOSE

Peptic Ulcer Disease (PUD) is the digestion of the digestive tube. PUD not only interferes with food digestion & nutrient absorption, damages one of the largest defensive barriers against pathogenic micro-organisms, but also impedes drug absorption & bioavailability, rendering the oral route, the most convenient way, ineffective. Omeprazole, one of the indispensable cost-effective proton-pump inhibitors (PPIs) extensively prescribed to control PUD, is showing growing apprehensions toward multiple drug interactions & side effects. Hence, finding a natural alternative with Omeprazole-like activity & limited side effects is a medical concern.

STUDY DESIGN

Therefore, we present Stemmoside C as a new gastroprotective phytochemical agent isolated from Solenostemma argel to be tested in upgrading doses against ethanol-induced gastric ulcers in mice compared to negative, positive, & reference Omeprazole groups.

METHODS

We carried out in-depth pharmacological & histopathological studies to determine the possible mechanistic pathway.

RESULTS

Our results showed that Stemmoside C protected the stomach against ethanol-induced gastric ulcers parallel to Omeprazole. Furthermore, the mechanistic studies revealed that Stemmoside C produced its effect using an orchestrated array of different mechanisms. Stemmoside C stimulates stomach defense by increasing COX-2, PGE-2, NO, & TFF-1 healing factors, IL-10 anti-inflammatory cytokine, & Nrf-2 & HO-1 anti-oxidant pathways. It also suppresses stomach ulceration by inhibiting leucocyte recruitment, especially neutrophils, leading to subsequent inhibition of NF-κBp65, TNF-α, IL-1β, & iNOS pro-inflammatory cytokines & JAK-1/STAT-3 inflammation-induced carcinogenicity cascade in addition to MMP-9 responsible for tissue degradation.

CONCLUSION

These findings cast light on Stemmoside C's clinical application against gastric ulcer progression, recurrence, & tumorigenicity & concurrently with chemotherapy.

Combined effect of pantoprazole and mesenchymal stem cells on experimentally induced gastric ulcer: implication of oxidative stress, inflammation and apoptosis pathways

Gastric ulcer (GU) is one of the most common diseases of the upper gastrointestinal tract that affects millions of people worldwide. This study aimed to investigate the possible alleviating effect of a combined treatment of pantoprazole (PANTO) and adipose tissue-derived mesenchymal stem cells (ADSCs) in comparison with each treatment alone on the healing process of the experimentally induced GU in rats, and to uncover the involved pathways. Rats were divided into five groups: (1) Control, (2) GU, (3) PANTO, (4) ADSCs and (5) ADSCs + PANTO. Markers of oxidative stress, inflammation and apoptosis were assessed. The current data indicated that PANTO-, ADSCs- and ADSCs + PANTO-treated groups showed significant drop (p < 0.05) in serum advanced oxidation protein products (AOPPs) and advanced glycation end products (AGEPs) along with significant elevation (p < 0.05) in serum TAC versus the untreated GU group. Moreover, the treated groups (PANTO, ADSCs and ADSCs + PANTO) displayed significant down-regulation (p < 0.05) in gastric nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), tumor necrosis factor alpha (TNF-α), cyclooxygenase-2 (COX-2), intercellular adhesion molecule-1 (ICAM-1), matrix metallopeptidase 9 (MMP-9) and caspase-3 along with significant up-regulation (p < 0.05) in vascular endothelial growth factor (VEGF) and peroxisome proliferator-activated receptor gamma (PPARγ) genes expression compared to the untreated GU group. Immunohistochemical examination of gastric tissue for transforming growth factor β1 (TGF-β1), epidermal growth factor (EGF) and proliferating cell nuclear antigen (PCNA) showed moderate to mild and weak immune reactions, respectively in the PANTO-, ADSCs- and ADSCs + PANTO-treated rat. Histopathological investigation of gastric tissue revealed moderate to slight histopathological alterations and almost normal histological features of the epithelial cells, gastric mucosal layer, muscularis mucosa and submucosa in PANTO-, ADSCs- and ADSCs + PANTO-treated rats, respectively. Conclusively, the co-treatment with ADSCs and PANTO evidenced sententious physiological protection against GU by suppressing oxidative stress, inhibiting inflammation and reducing apoptosis with consequent acceleration of gastric tissue healing process.

A Structural Proteome Screen Identifies Protein Mimicry in Host-Microbe Systems

Host-microbe systems are evolutionary niches that produce coevolved biological interactions and are a key component of global health. However, these systems have historically been a difficult field of biological research due to their experimental intractability. Impactful advances in global health will be obtained by leveraging in silico screens to identify genes involved in mediating interspecific interactions. These predictions will progress our understanding of these systems and lay the groundwork for future in vitro and in vivo experiments and bioengineering projects. A driver of host-manipulation and intracellular survival utilized by host-associated microbes is molecular mimicry, a critical mechanism that can occur at any level from DNA to protein structures. We applied protein structure prediction and alignment tools to explore host-associated bacterial structural proteomes for examples of protein structure mimicry. By leveraging the Legionella pneumophila proteome and its many known structural mimics, we developed and validated a screen that can be applied to virtually any host-microbe system to uncover signals of protein mimicry. These mimics represent candidate proteins that mediate host interactions in microbial proteomes. We successfully applied this screen to other microbes with demonstrated effects on global health, Helicobacter pylori and Wolbachia , identifying protein mimic candidates in each proteome. We discuss the roles these candidates may play in important Wolbachia -induced phenotypes and show that Wobachia infection can partially rescue the loss of one of these factors. This work demonstrates how a genome-wide screen for candidates of host-manipulation and intracellular survival offers an opportunity to identify functionally important genes in host-microbe systems.

Immune evasion by proteolytic shedding of natural killer group 2, member D ligands in Helicobacter pylori infection

Background

Helicobacter pylori (H. pylori) uses various strategies that attenuate mucosal immunity to ensure its persistence in the stomach. We recently found evidence that H. pylori might modulate the natural killer group 2, member 2 (NKG2D) system. The NKG2D receptor and its ligands are a major activation system of natural killer and cytotoxic T cells, which are important for mucosal immunity and tumor immunosurveillance. The NKG2D system allows recognition and elimination of infected and transformed cells, however viruses and cancers often subvert its activation. Here we aimed to identify a potential evasion of the NKG2D system in H. pylori infection.

Methods

We analyzed expression of NKG2D system genes in gastric tissues of H. pylori gastritis and gastric cancer patients, and performed cell-culture based infection experiments using H. pylori isogenic mutants and epithelial and NK cell lines.

Results

In biopsies of H. pylori gastritis patients, NKG2D receptor expression was reduced while NKG2D ligands accumulated in the lamina propria, suggesting NKG2D evasion. In vitro, H. pylori induced the transcription and proteolytic shedding of NKG2D ligands in stomach epithelial cells, and these effects were associated with specific H. pylori virulence factors. The H. pylori-driven release of soluble NKG2D ligands reduced the immunogenic visibility of infected cells and attenuated the cytotoxic activity of effector immune cells, specifically the anti-tumor activity of NK cells.

Conclusion

H. pylori manipulates the NKG2D system. This so far unrecognized strategy of immune evasion by H. pylori could potentially facilitate chronic bacterial persistence and might also promote stomach cancer development by allowing transformed cells to escape immune recognition and grow unimpeded to overt malignancy.

Expression of Matrix Metalloproteinases in the Circulating Immune Cells in Children with Helicobacter pylori Infection-Correlation with Clinical Factors

H. pylori gastritis is strongly associated with the upregulation of the expression of several matrix metalloproteinases (MMPs) in the gastric mucosa. However, the role of MMP-2 and MMP-9, and their inhibitors (tissue inhibitors of metalloproteinases -TIMPs) produced by immune cells in infected children have not been clearly defined. Moreover, the effects of H. pylori eradication therapy on MMPs and TIMPs production has not been evaluated. A total of 84 children were studied: 24-with newly diagnosed H. pylori gastritis, 25-after H. pylori eradication therapy (17 of them after successful therapy), 24-with H. pylori-negative gastritis, and 11-controls. Plasma levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 by ELISA; MMPs and TIMPs expression in lymphocytes; neutrophils and monocytes in peripheral blood by multiparameter flow cytometry; and mucosal mRNA expression levels of MMPs and TIMP-1 in gastric biopsies by RT-PCR were evaluated. Children with H. pylori-related gastritis showed the following: (1) increased MMP-2 and TIMP-2 plasma levels, (2) increased intracellular expression of MMP-2 in the circulating lymphocytes and neutrophils, (3) low frequencies of circulating TIMP-1+ and TIMP-2+ leukocytes, and (4) high expression of mRNA for MMP-9 along with low expression of mRNA for MMP-2 in the gastric mucosa. Unsuccessful H. pylori eradication was associated with the following: (1) high plasma levels of MMP-9 and TIMP-1, (2) increased pool of TIMP-1+ lymphocytes as well as high expression of MMP-9 in circulating lymphocytes, and (3) high expression of mRNA for MMP-9 in the gastric mucosa. Our data suggest that MMPs are important contributors to stomach remodelling in children with H. pylori-related gastritis. Unsuccessful H. pylori eradication is associated with increased MMP-9 in plasma, circulating lymphocytes, and gastric mucosa.

Induction of MMP-3 and MMP-9 expression during Helicobacter pylori infection via MAPK signaling pathways

BACKGROUND AND AIMS

Helicobacter pylori (H. pylori)-induced gastric pathology involves remodeling of extracellular matrix mediated by aberrant activity of matrix metalloproteinases (MMPs). We have previously shown that in vitro H. pylori infection leads to MMP-3 and MMP-9 overexpression, associated with phosphorylation of bacterial oncoprotein CagA. We extended these findings in an in vivo model of H. pylori infection and further assessed the involvement of MAPK pathways in MMP expression.

MATERIALS AND METHODS

C57BL/6 mice were infected with H. pylori strains HPARE, HPARE ΔCagA, and SS1, for 6 and 9 months. Transcriptional expression of Mmp-3 and Mmp-9 was evaluated via qPCR while respective protein levels in the gastric mucosa were determined immunohistochemically. Epithelial cell lines AGS and GES-1 were infected with H. pylori strain P12 in the presence of chemical inhibitors of JNK, ERK1/2, and p38 pathways, for 24 h. mRNA and protein expression of MMP-3 and MMP-9 were determined via qPCR and Western blot, respectively.

RESULTS

We observed transcriptional activation of Mmp-3 and Mmp-9 as well as aberrant MMP-3 and MMP-9 protein expression in murine gastric tissue following H. pylori infection. CagA expression was associated with MMP upregulation, particularly during the early time points of infection. We found that inhibition of ERK1/2 resulted in reduced mRNA and protein expression of MMP-3 and MMP-9 during H. pylori infection, in both cell lines. Expressed protein levels of both MMPs were also found reduced in the presence of JNK pathway inhibitors in both cell lines. However, p38 inhibition resulted in a more complex effect, probably attributed to the accumulation of phospho-p38 and increased phospho-ERK1/2 activity due to crosstalk between MAPK pathways.

CONCLUSIONS

H. pylori colonization leads to the upregulation of MMP-3 and MMP-9 in vivo, which primarily involves ERK1/2 and JNK pathways. Therefore, their inhibition may potentially offer a protective effect against gastric carcinogenesis and metastasis.

Helicobacter pylori regulates stomach diseases by activating cell pathways and DNA methylation of host cells

One of the most prevalent malignant tumors of the digestive tract is gastric cancer (GC). Age, high salt intake, Helicobacter pylori (H. pylori) infection, and a diet deficient in fruits and vegetables are risk factors for the illness. A significant risk factor for gastric cancer is infection with H. pylori. Infecting gastric epithelial cells with virulence agents secreted by H. pylori can cause methylation of tumor genes or carcinogenic signaling pathways to be activated. Regulate downstream genes' aberrant expression, albeit the precise mechanism by which this happens is unclear. Oncogene, oncosuppressor, and other gene modifications, as well as a number of different gene change types, are all directly associated to the carcinogenesis of gastric cancer. In this review, we describe comprehensive H. pylori and its virulence factors, as well as the activation of the NF-κB, MAPK, JAK/STAT signaling pathways, and DNA methylation following infection with host cells via virulence factors, resulting in abnormal gene expression. As a result, host-related proteins are regulated, and gastric cancer progression is influenced. This review provides insight into the H. pylori infection, summarizes a series of relevant papers, discusses the complex signaling pathways underlying molecular mechanisms, and proposes new approach to immunotherapy of this important disease.

Activation of Laminin γ2 by Helicobacter pylori Promotes Invasion and Survival of Gastric Cancer Cells With E-Cadherin Defects

BACKGROUND

Helicobacter pylori infection induces cellular phenotypes relevant for cancer progression, namely cell motility and invasion. We hypothesized that the extracellular matrix (ECM) could be involved in these deleterious effects.

METHODS

Microarrays were used to uncover ECM interactors in cells infected with H. pylori. LAMC2, encoding laminin γ2, was selected as a candidate gene and its expression was assessed in vitro and in vivo. The role of LAMC2 was investigated by small interference RNA (siRNA) combined with a set of functional assays. Laminin γ2 and E-cadherin expression patterns were evaluated in gastric cancer cases.

RESULTS

Laminin γ2 was found significantly overexpressed in gastric cancer cells infected with H. pylori. This finding was validated in vitro by infection with clinical isolates and in vivo by using gastric biopsies of infected and noninfected individuals. We showed that laminin γ2 overexpression is dependent on the bacterial type IV secretion system and on the CagA. Functionally, laminin γ2 promotes cell invasion and resistance to apoptosis, through modulation of Src, JNK, and AKT activity. These effects were abrogated in cells with functional E-cadherin.

CONCLUSIONS

These data highlight laminin γ2 and its downstream effectors as potential therapeutic targets, and the value of H. pylori eradication to delay gastric cancer onset and progression.

Pathophysiological Role of Chymase-Activated Matrix Metalloproteinase-9

Chymase present in mast cells can directly form matrix metalloproteinase (MMP)-9 from proMMP-9. Chymase-activated MMP-9 has been reportedly closely related to the pathogenesis of various diseases, and inflammation-related diseases in particular. Upregulated chymase and MMP-9 have been observed in tissues from patients and animal models of aortic aneurysm, inflammatory gastrointestinal and hepatic diseases, acute pancreatic failure, atopic dermatitis and rheumatoid arthritis. Chymase at these regions is only derived from mast cells, while MMP-9 is derived from macrophages and neutrophils in addition to mast cells. Chymase inhibitors attenuate MMP-9 formation from pro-MMP-9, and ameliorate the development and progression of these disorders, along with reduction in inflammatory cell numbers. MMP-9 activated by chymase might also be involved in angiogenesis in the tumor environment. Development of angiogenesis around several cancers is closely related to the expression of chymase and MMP-9, and postoperative survival curves have revealed that patients with a higher number of chymase positive cells have lower survival rates. In this review, we wanted to clarify the role of chymase-activated MMP-9, which might become an important therapeutic target for various inflammatory disorders.

Bacterial Involvement in Progression and Metastasis of Adenocarcinoma of the Stomach

Simple Summary

Infectious bacteria influence primary gastric carcinogenesis, organotropism, and metastatic progression by altering the microenvironment at the primary and secondary tumors. Key species include Helicobacter pylori (H. pylori) and Mycoplasma hyorhinis (M. hyorhinis). Inflammation caused by H. pylori virulence factors, such as CagA, VacA, and oipA, disrupt epithelial integrity, which allows the primary tumor to progress through the metastatic process. Evidence supports the activation of aquaporin-5 by CagA-positive H. pylori infection, promoting epithelial–mesenchymal transition via the extracellular signal-regulated kinase/mitogen-activated protein kinase (MEK/ERK) pathway, thus laying the foundation for metastatic disease. M. hyorhinis has also been implicated in gastric neoplasia via β-catenin stabilization and subsequent activation of the WNT-signaling pathway, promoting gastric cancer cell motility and inciting cancer progression.

Abstract

Gastric cancer metastasis is a process in which the tumor microenvironment may carry significant influence. Helicobacter pylori (H. pylori) infection is well-established as a contributor to gastric carcinoma. However, the role that these bacteria and others may play in gastric carcinoma metastasis is a current focus of study. A review of the literature was conducted to elucidate the process by which gastric adenocarcinoma metastasizes, including its ability to utilize both the lymphatic system and the venous system to disseminate. Studies that investigate the tumor microenvironment at both the primary and secondary sites were assessed in detail. H. pylori and Mycoplasma hyorhinis (M. hyorhinis) were found to be important drivers of the pathogenesis of gastric adenocarcinoma by modifying various steps in cell metastasis, including epithelial–mesenchymal transition, cell migration, and cell invasion. H. pylori is also a known driver of MALT lymphoma, which is often reversible simply with the eradication of infection. M. hyorhinis has been implicated in gastric neoplasia via β-catenin stabilization and subsequent activation of the WNT-signaling pathway, promoting gastric cancer cell motility and inciting cancer progression. Fusobacterium nucleatum (F. nucleatum) and its association with worse prognosis in diffuse-type gastric adenocarcinoma are also reviewed. Recognition of the roles that bacteria play within the metastatic cascade is vital in gastrointestinal adenocarcinoma treatment and potential reoccurrence. Further investigation is needed to establish potential treatment for metastatic gastric carcinoma by targeting the tumor microenvironment.

Astaxanthin Inhibits Matrix Metalloproteinase Expression by Suppressing PI3K/AKT/mTOR Activation in Helicobacter pylori-Infected Gastric Epithelial Cells

Helicobacter pylori (H. pylori) increases production of reactive oxygen species (ROS) and activates signaling pathways associated with gastric cell invasion, which are mediated by matrix metalloproteinases (MMPs). We previously demonstrated that H. pylori activated mitogen-activated protein kinase (MAPK) and increased expression of MMP-10 in gastric epithelial cells. MMPs degrade the extracellular matrix, enhancing tumor invasion and cancer progression. The signaling pathway of phosphatidylinositol 3-kinase (PI3K)/serine/threonine protein kinase B (AKT)/mammalian target of rapamycin (mTOR) is associated with MMP expression. ROS activates PIK3/AKT/mTOR signaling in cancer. Astaxanthin, a xanthophyll carotenoid, shows antioxidant activity by reducing ROS levels in gastric epithelial cells infected with H. pylori. This study aimed to determine whether astaxanthin inhibits MMP expression, cell invasion, and migration by reducing the PI3K/AKT/mTOR signaling in H. pylori-infected gastric epithelial AGS cells. H. pylori induced PIK3/AKT/mTOR and NF-κB activation, decreased IκBα, and induced MMP (MMP-7 and -10) expression, the invasive phenotype, and migration in AGS cells. Astaxanthin suppressed these H. pylori-induced alterations in AGS cells. Specific inhibitors of PI3K, AKT, and mTOR reversed the H. pylori-stimulated NF-κB activation and decreased IκBα levels in the cells. In conclusion, astaxanthin suppressed MMP expression, cell invasion, and migration via inhibition of PI3K/AKT/mTOR/NF-κB signaling in H. pylori-stimulated gastric epithelial AGS cells.

NF-κB Regulation by Gut Microbiota Decides Homeostasis or Disease Outcome During Ageing

Human beings and their indigenous microbial communities have coexisted for centuries, which led to the development of co-evolutionary mechanisms of communication and cooperation. Such communication machineries are governed by sophisticated multi-step feedback loops, which typically begin with the recognition of microbes by pattern recognition receptors (PRRs), followed by a host transcriptional response leading to the release of effector molecules. Our gastrointestinal tract being the main platform for this interaction, a variety of host intestinal cells tightly regulate these loops to establish tolerance towards the microbial communities of the gut and maintain homeostasis. The transcription factor, nuclear factor kappa B (NF-κB) is an integral component of such a communication apparatus, which plays a critical role in determining the state of homeostasis or inflammation associated with dysbiosis in the host. Here we outline the crucial role of NF-κB in host response to microbial cues in the context of ageing and associated diseases.

The impact of oral ciprofloxacin on the structure and functions of rat gastric mucosa

Ciprofloxacin (CPX), is a fluoroquinolone antibiotic used to treat a number of gram-negative and gram-positive bacterial infections. Ciprofloxacin can cause severe side effects, ranging from tendon problems, nerve damage, to serious mood or behavior changes.

The purpose of this study was to investigate how ciprofloxacin affects gastric cell lines in rats with a distinctive emphasis on physiological, histopathological, and bacteriological changes. Male albino rats (n = 21) were distributed into three groups; control, CPX, and CPX-withdrawal groups. The treated rats were given CPX tablets (12.5 mg/kg) dissolved in carboxymethyl cellulose (CMC) 0.5% orally once daily via gavage for sixty consecutive days. Control rats received only the vehicle. The withdrawal group was treated for 60 days and the drug was withdrawn for another sixty days. After completion of the experiment, all rats were sacrificed and gastric tissues were treated for light, immunohistochemical, and scanning electron microscopic examination. Image J software was used to measure immune-labeled gastric epithelial cells. Blood samples were also collected for H. Pylori immunoglobulins IgM, IgA, and IgG. Results showed that treated rats acquired significantly strongly positive tumor necrosis factor (TNFα) and significant reduction of serum level of H. pylori IgM, IgA, and IgG in all the study groups. It could be concluded that prolonged oral CPX administration to albino rats changes the gastric mucosal architecture and bacteriology.

Proteolytic Landscapes in Gastric Pathology and Cancerogenesis

Gastric cancer is a leading cause of cancer-related death, and a large proportion of cases are inseparably linked to infections with the bacterial pathogen and type I carcinogen Helicobacter pylori. The development of gastric cancer follows a cascade of transformative tissue events in an inflammatory environment. Proteases of host origin as well as H. pylori-derived proteases contribute to disease progression at every stage, from chronic gastritis to gastric cancer. In the present article, we discuss the importance of (metallo-)proteases in colonization, epithelial inflammation, and barrier disruption in tissue transformation, deregulation of cell proliferation and cell death, as well as tumor metastasis and neoangiogenesis. Proteases of the matrix metalloproteinase (MMP) and a disintegrin and metalloproteinase domain-containing protein (ADAM) families, caspases, calpain, and the H. pylori proteases HtrA, Hp1012, and Hp0169 cleave substrates including extracellular matrix molecules, chemokines, and cytokines, as well as their cognate receptors, and thus shape the pathogenic microenvironment. This review aims to summarize the current understanding of how proteases contribute to disease progression in the gastric compartment.

Matrix Metalloproteinases in Helicobacter pylori-Associated Gastritis and Gastric Cancer

Gastric cancer is one of the leading causes of the cancer-related mortality worldwide. The etiology of this disease is complex and involves genetic predisposition and environmental factors, including Helicobacter pylori. Infection of the stomach with H. pylori leads to gastritis and gastric atrophy, which can progress stepwise to gastric cancer. Matrix metalloproteinases (MMPs) actively participate in the pathology development. The further progression of gastric cancer seems to be less dependent on bacteria but of intra-tumor cell dynamics. Bioinformatics data confirmed an important role of the extracellular matrix constituents and specific MMPs in stomach carcinoma invasion and metastasis, and revised their potential as predictors of the disease outcome. In this review, we describe, in detail, the impact of MMPs in H. pylori-associated gastritis and gastric cancer.

Identification of Desmoglein-2 as a novel target of Helicobacter pylori HtrA in epithelial cells

BACKGROUND

High temperature requirement A (HtrA) is an active serine protease secreted by the group-I carcinogen Helicobacter pylori (H. pylori). The human cell adhesion protein and tumor suppressor E-cadherin (hCdh1) expressed on the surface of gastric epithelial cells was identified as the first HtrA substrate. HtrA-mediated hCdh1 cleavage and subsequent disruption of intercellular adhesions are considered as important steps in H. pylori pathogenesis. In this study, we performed a proteomic profiling of H. pylori HtrA (HpHtrA) to decipher the complex mechanism of H. pylori interference with the epithelial barrier integrity.

RESULTS

Using a proteomic approach we identified human desmoglein-2 (hDsg2), neuropilin-1, ephrin-B2, and semaphorin-4D as novel extracellular HpHtrA substrates and confirmed the well characterized target hCdh1. HpHtrA-mediated hDsg2 cleavage was further analyzed by in vitro cleavage assays using recombinant proteins. In infection experiments, we demonstrated hDsg2 shedding from H. pylori-colonized MKN28 and NCI-N87 cells independently of pathogen-induced matrix-metalloproteases or ADAM10 and ADAM17.

CONCLUSIONS

Characterizing the substrate specificity of HpHtrA revealed efficient hDsg2 cleavage underlining the importance of HpHtrA in opening intercellular junctions. Video Abstract.

Expression of Matrix Metalloproteinase-9 in Gastric Cancer

Background Matrix-metalloproteinase-9 (MMP-9) is expressed by a wide range of cells and plays a significant role in the regulation of the tumor microenvironment of various cancers including gastric cancer. This study aims at the correlation of MMP-9 expression in gastric cancer with existing prognostic factors. Methods The MMP-9 expression in gastric cancer was identified by immunohistochemistry using a monoclonal antibody in paraffin-embedded sections, correlated with various clinicopathological parameters, and statistically analyzed. Results MMP-9 expression in gastric cancer was significantly correlated with the grade, depth of invasion, and TNM stage (p-value = 0.003, 0.019, and 0.025, respectively). A significant difference in expression between tumor tissue and adjacent gastric mucosa (p-value = 0.000) was also observed. 100% negative expression was found in well-differentiated tumors and early gastric carcinoma (T1). Conclusion The study results suggest that MMP-9 expression could be a potential biomarker of aggressive gastric cancer and candidates for the possible diagnostic and prognostic tool.

Association of the functionally significant polymorphisms of the MMP9 gene with H. pylori-positive gastric ulcer in the Caucasian population of Central Russia

Background and purpose

The study analyzed the association of functionally significant polymorphisms of matrix metalloproteinases (MMPs) genes with the development of gastric ulcer (GU) in Caucasians from Central Russia.

Methods

The 781 participants, including 434 patients with GU (196 Helicobacter pylori (H. pylori)-positive and 238 H. pylori-negative) and 347 controls (all H. pylori-negative) were recruited for the study. Ten SNPs of the MMP1 (rs1799750), MMP2 (rs243865), MMP3 (rs679620), MMP8 (rs1940475), and MMP9 (rs3918242, rs3918249, rs3787268, rs17576, rs17577, and rs2250889) genes were considered for association with GU using multiple logistic regression. The SNPs associated with GU and loci linked (r²≥0.8) to them were analyzed in silico for their functional assignments.

Results

The SNPs of the MMP9 gene were associated with H. pylori-positive GU: alleles C of rs3918249 (OR = 2.02, p_perm = 0.008) and A of rs3787268 (OR = 1.60–1.82, p_perm ≤ 0.016), and eight haplotypes of all studied MMP9 gene SNPs (OR = 1.85–2.04, p_perm ≤ 0.016) increased risk for H. pylori-positive GU. None of the analyzed SNPs was independently associated with GU and H. pylori-negative GU. Two haplotypes of the MMP9 gene (contributed by rs3918242, rs3918249, rs17576, and rs3787268) increased risk for GU (OR = 1.62–1.65, p_perm ≤ 0.006). Six loci of the MMP9 gene, which are associated with H. pylori-positive GU, and 65 SNPs linked to them manifest significant epigenetic effects, have pronounced eQTL (17 genes) and sQTL (6 genes) values.

Conclusion

SNPs of the MMP9 were associated with H. pylori-positive GU but not with H. pylori-negative GU in Caucasians of Central Russia.

Emerging therapeutic targets for gastric cancer from a host-Helicobacter pylori interaction perspective

INTRODUCTION

Gastric cancer (GC) has the higher genetic, cytologic, and architectural heterogeneity compared to other gastrointestinal cancers. By inducing gastric inflammation, Helicobacter pylori (HP) may lead to GC through combining bacterial factors with host factors. In this regard, identification of the major therapeutic targets against the host-HP interactions plays a critical role in GC prevention, diagnosis, and treatment.

AREAS COVERED

This study offers new insights into the promising therapeutic targets against the angiogenesis, invasion, or metastasis of GC from a host-HP interaction perspective. To this end, MEDLINE, EMBASE, LILACS, AIM, and IndMed databases were searched for relevant articles since 1992.

EXPERT OPINION

Wnt signaling and COX pathway have a well-documented history in the genesis of GC by HP and might be considered as the most promising targets for early GC treatment. Destroying HP may decrease the risk of GC, but it cannot fully hinder the GC development induced by HP infection. Therefore, targeting HP-activated pathways, especially COX-2/Wnt/beta-catenin/VEGF, TLR2/TLR9/COX-2, COX2-PGE2, and NF-κB/COX-2, as well as EPHA2, MMPs, and miR-543/SIRT1 axis, can be an effective measure in the early treatment of GC. However, different clinical trials and large, multi-center cohorts are required to validate these potentially effective targets for GC therapy.

Functionally significant polymorphisms of the MMP-9 gene are associated with peptic ulcer disease in the Caucasian population of Central Russia

This study analyzed the association of functionally significant SNPs of matrix metalloproteinase (MMP) genes in the development of peptic ulcer disease (PUD) in Caucasians from Central Russia. Ten SNPs of the MMP-1, MMP-2, MMP-3, MMP-8, and MMP-9 genes were analyzed for association with PUD in a cohort of 798 patients with PUD (including 404 H. pylori-positive and 394 H. pylori-negative) and 347 H. pylori-negative controls using logistic regression and assuming the additive, recessive, and dominant genetic models. The variants of MMP-1, MMP-2, MMP-3, and MMP-8 did not manifest any significant associations with the diseases. Five SNPs of the MMP-9 gene demonstrated such association. Allele G of the rs17576 MMP-9 locus conferred a higher risk for PUD (OR_adj = 1.31, p_perm = 0.016), haplotype AACG of loci rs17576-rs3787268-rs2250889-rs17577 of the MMP-9 gene decreased risk for PUD (OR_adj = 0.17, p_perm = 0.003). Also, allele C of rs3918249, allele G of rs17576 and haplotype CG of rs3918249-rs17576 of the MMP-9 gene increased risk for H. pylori-positive PUD (OR_adj = 1.82, p_perm = 0.002; OR_adj = 1.53–1.95 p_perm = 0.001–0.013 and OR_adj = 1.49 p_perm = 0.009 respectively). The above loci and 50 linked to them possess significant regulatory effects and may affect the alternative splicing of four genes and the expression of 17 genes in various organs and tissues related to the PUD pathogenesis.

Matrix Metalloproteinase-9 (MMP-9) induced disruption of intestinal epithelial tight junction barrier is mediated by NF-κB activation

BACKGROUND

Matrix Metalloproteinase-9 (MMP-9) has been shown to play a key role in mediating inflammation and tissue damage in inflammatory bowel disease (IBD). In patients with IBD, the intestinal tight junction (TJ) barrier is compromised as characterized by an increase in intestinal permeability. MMP-9 is elevated in intestinal tissue, serum and stool of patients with IBD. Previous studies from our laboratory showed that MMP-9 causes an increase in intestinal epithelial TJ permeability and that the MMP-9 induced increase in intestinal permeability is an important pathogenic factor contributing to the development of intestinal inflammation in IBD. However, the intracellular mechanisms that mediate the MMP-9 modulation of intestinal barrier function remain unclear.

AIMS

The main aim of this study was to further elucidate the molecular mechanisms involved in MMP-9 induced increase in intestinal epithelial TJ permeability using Caco-2 monolayers as an in-vitro model system.

RESULTS

MMP-9 induced increase in Caco-2 TJ permeability was associated with activation and cytoplasmic-to-nuclear translocation of NF-κB p65. Knocking-down NF-κB p65 by siRNA transfection prevented the MMP-9 induced expression of the NF-κB target gene IL-8, myosin light chain kinase (MLCK) protein expression, and subsequently prevented the increase in Caco-2 TJ permeability. In addition, the effect of MMP-9 on Caco-2 intestinal epithelial TJ barrier function was not mediated by apoptosis or necrosis.

CONCLUSION

Our data show that the MMP-9 induced disruption of Caco-2 intestinal epithelial TJ barrier function is regulated by NF-κB pathway activation of MLCK.

β-Carotene Inhibits Expression of Matrix Metalloproteinase-10 and Invasion in Helicobacter pylori-Infected Gastric Epithelial Cells

Matrix metalloproteinases (MMPs), key molecules of cancer invasion and metastasis, degrade the extracellular matrix and cell–cell adhesion molecules. MMP-10 plays a crucial role in Helicobacter pylori-induced cell-invasion. The mitogen-activated protein kinase (MAPK) signaling pathway, which activates activator protein-1 (AP-1), is known to mediate MMP expression. Infection with H. pylori, a Gram-negative bacterium, is associated with gastric cancer development. A toxic factor induced by H. pylori infection is reactive oxygen species (ROS), which activate MAPK signaling in gastric epithelial cells. Peroxisome proliferator-activated receptor γ (PPAR-γ) mediates the expression of antioxidant enzymes including catalase. β-Carotene, a red-orange pigment, exerts antioxidant and anti-inflammatory properties. We aimed to investigate whether β-carotene inhibits H. pylori-induced MMP expression and cell invasion in gastric epithelial AGS (gastric adenocarcinoma) cells. We found that H. pylori induced MMP-10 expression and increased cell invasion via the activation of MAPKs and AP-1 in gastric epithelial cells. Specific inhibitors of MAPKs suppressed H. pylori-induced MMP-10 expression, suggesting that H. pylori induces MMP-10 expression through MAPKs. β-Carotene inhibited the H. pylori-induced activation of MAPKs and AP-1, expression of MMP-10, and cell invasion. Additionally, it promoted the expression of PPAR-γ and catalase, which reduced ROS levels in H. pylori-infected cells. In conclusion, β-carotene exerts an inhibitory effect on MAPK-mediated MMP-10 expression and cell invasion by increasing PPAR-γ-mediated catalase expression and reducing ROS levels in H. pylori-infected gastric epithelial cells.

A novel gastroprotective effect of zeaxanthin against stress-induced gastritis in male rats targeting the expression of HIF-1α, TFF-1 and MMP-9 through PI3K/Akt/JNK signaling pathway

Stress-induced gastritis is a common problem in the intensive care unit. Zeaxanthin (ZE), a non-provitamin A carotenoid has been known to exert antioxidant and anti-inflammatory effects. In this study, we examined the effect of ZE on water avoidance stress (WAS)-induced gastritis in rats. 24 Sprague' Dawley male rats were divided into four groups; control, ZE, WAS and WAS+ZE. In the stressed rats, treatment with ZE effectively downregulated the gastric levels of total oxidant status (TOS), myeloperoxidase (MPO) and malondialdehyde (MDA), with significant upregulation of the antioxidant enzymes' activities and gastric levels of prostagladin-E2 (PGE2) as compared to the untreated stressed one. As noticed in the present study, ZE significantly decrease the gastric levels of interleukin-1 β (IL-1β) and IL-6 as well as suppression of nuclear transcription factor kappa-B (NF-κB) immunohistochemical expression together with upregulation of trefoil factor-1 (TFF-1) gene expression. Moreover, in the untreated WAS-induced gastritis group, gastrin and corticosterone levels were significantly increased together with upregulation of the gene expression of hypoxia inducible factor-1α (HIF-1α), matrix metalloproteinase-9 (MMP-9), PI3K, Akt and JNK in the gastric tissues, which significantly improved by ZE administration. These all positive effects of ZE reflected on reduction of microscopic gastric mucosal damage and inflammatory cell infiltration with improvement of ulcer score. Our results discover that ZE has a new gastroprotective effect against stress-induced gastritis in rats, primarily through its antioxidative and anti-inflammatory effects, which are expressed in the regulation of the MMP-9 and HIF-1α signaling pathways.

Dobera glabra (Forssk.) Poir. (Salvadoraceae); phenolic constituents of the aqueous leaves extract and evaluation of its anti-inflammatory, analgesic activities

BACKGROUND

The plant kingdom is considered one of the most common sources for structural and biological diversity. In particular, the wild category acquires our attention to investigate the phytochemical and the biological evaluations.

METHODS

Dobera glabra was exposed to phytochemical examination using HPLC-ESI-MS analysis. Furthermore, the anti-inflammatory activity was evaluated using carrageenan-induced rat paw edema model, whereas both the central and peripheral analgesic activities were tested via hot plate test in rats and acetic acid-induced writhing in mice, respectively.

RESULTS

Twenty phenolic compounds of D. glabra aqueous leaves extract were emphasized by liquid chromatography coupled with mass spectrometry. Moreover, D. glabra exhibited both anti-inflammatory and peripheral analgesic activities. Furthermore, D. glabra significantly decreased the immune expression of MMP-9, TNF-α and TGF-β1 in the hind paw of rats.

CONCLUSION

D. glabra possess peripheral anti-nociceptive and anti-inflammatory effects in rats mediated through its anti-oxidant and anti-inflammatory activities. The activity of D. glabra leaves extract might be attributed to the presence of hydroxy and keto structures.

Carnosine Suppresses Human Colorectal Cell Migration and Intravasation by Regulating EMT and MMP Expression

Carnosine is an endogenous dipeptide found in the vertebrate skeletal muscles that is usually obtained through the diet. To investigate the mechanism by which carnosine regulates the migration and intravasation of human colorectal cancer (CRC) cells, we used cultured HCT-116 cells as an experimental model in this study. We examined HCT-116 cell migratory and intravasive abilities and expression of epithelial-mesenchymal transition (EMT)-associated molecules and matrix metalloproteinases (MMPs) after carnosine treatment. The results showed that both migration and invasion were inhibited in cells treated with carnosine. We found significant decreases in Twist-1 protein levels and increases in E-cadherin protein levels in HCT-116 cells after carnosine exposure. Although plasminogen activator (uPA) and MMP-9 mRNA and protein levels were decreased, TIMP-1 mRNA and protein levels were increased. Furthermore, the cytosolic levels of phosphorylated I κ B (p-I κ B) and NF- κ B DNA-binding activity were reduced after carnosine treatment. These results indicate that carnosine inhibits the migration and intravasation of human CRC cells. The regulatory mechanism may occur by suppressing NF- κ B activity and modulating MMP and EMT-related gene expression in HCT-116 cells.

Involvement of microRNAs-MMPs-E-cadherin in the migration and invasion of gastric cancer cells infected with Helicobacter pylori

It has been found that Helicobacter pylori （H. pylori）is not only the main cause of gastric cancer, but also closely related to its metastasis. E-cadherin cleavage induced by matrix metalloproteinases (MMPs) plays an important role in the tumor metastasis. In the present study, we investigated the role of microRNAs-MMPs-E-cadherin in migration and invasion of gastric cancer cells treated with H. pylori. The results showed that H. pylori induced migration and invasion of SGC-7901 cells with a down-regulation of E-cadherin expression, which were abolished by MMPs knock down, E-cadherin overexpression, mimics of miR128 and miR148a. MiR128/miR148a inhibitors restored MMP-3/MMP-7 expression, down-regulated E-cadherin level, and accelerated cellular migration and invasion. This study suggests that H. pylori induces migration and invasion of gastric cancer cells through reduction of E-cadherin function by activation of MMP-3, - 7. The present results also suggest that the activated MMPs/E-cadherin pathway is related with down-regulation of miR128/miR148a in the human gastric cancer cells infected with H. pylori.

A Novel Role of Irbesartan in Gastroprotection against Indomethacin-Induced Gastric Injury in Rats: Targeting DDAH/ADMA and EGFR/ERK Signaling

The advent of angiotensin II type 1 receptor blockers (ARBs) as intriguing gastroprotective candidates and the superior pharmacokinetics and pharmacodynamics displayed by irbesartan compared to many other ARBs raised the interest to investigate its gastroprotective potential in a rat model of gastric injury. Irbesartan (50 mg/Kg) was orally administered to male Wistar rats once daily for 14 days; thereafter gastric injury was induced by indomethacin (60 mg/Kg, p.o). Irbesartan reduced gastric ulcer index, gastric acidity, and ameliorated indomethacin-induced gastric mucosal apoptotic and inflammatory aberrations, as demonstrated by hampering caspase-3, prostaglandin E₂ and tumor necrosis factor-alpha levels and cyclooxygenase-2 mRNA expression. This ARB increased mucosal dimethylarginine dimethylaminohydrolase-1 (DDAH-1) gene expression and decreased elevated levels of matrix metalloproteinase-9, asymmetric dimethylarginine (ADMA), epidermal growth factor receptor (EGFR) mRNA and phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2). Histopathological evaluation corroborated biochemical findings. Overall efficacy of irbesartan was comparable to ranitidine, the widely used H₂ receptor blocker. In conclusion, irbesartan exerts significant gastroprotection against indomethacin-induced mucosal damage via acid-inhibitory, anti-inflammatory, anti-apoptotic and extracellular matrix remodeling mechanisms that are probably mediated, at least partly, by down-regulating DDAH/ADMA and EGFR/ERK1/2 signaling.

Insulin-like growth factor binding protein-1 (IGFBP-1) upregulated by Helicobacter pylori and is associated with gastric cancer cells migration

Insulin-like growth factor binding protein-1 (IGFBP-1), a secreted protein, implicated of various cells in mediating the proliferation, migration, invasion, adhesion, survival and so on. In this study, we assessed the expression and release of IGFBP-1 from gastric cancer cells with H. pylori 26695 infection and the biological functions of IGFBP-1 in gastric cancer cells. The results showed that the expression and release of IGFBP-1 were increased in gastric cancer cells (MGC-803, BGC-823, SGC-7901) infected with H. pylori 26695. In addition, the upregulation of IGFBP-1 was dose-dependent in BGC-823 cells infected with H. pylori 26695 but not time-dependent. The upregulation of IGFBP-1 got to peak at 12h after H. pylori 26695 infection and then decreased over time. Subsequently, we measured its functions by silencing and overexpressing IGFBP1 which suggested that overexpression of IGFBP-1 could inhibit the migration of BGC-823 and SGC-7901 cells. However, knocking down the IGFBP-1 could increase the migration of BGC-823 and SGC-7901 cells. Functional findings illustrated that IGFBP-1 was implicated in H. pylori 26695-induced MMP-9 expression in BGC-823 cells. In addition, overexpressing IGFBP1 reduce the promoting effect of MMP-9 on the BGC-823 cells migration. In summary, we demonstrated that IGFBP-1 suppress the migration of BGC-823 cells and play a protective role in the process of H. pylori-induced gastric cancer.

Proteolysis in Helicobacter pylori-Induced Gastric Cancer

Persistent infections with the human pathogen and class-I carcinogen Helicobacter pylori (H. pylori) are closely associated with the development of acute and chronic gastritis, ulceration, gastric adenocarcinoma and lymphoma of the mucosa-associated lymphoid tissue (MALT) system. Disruption and depolarization of the epithelium is a hallmark of H. pylori-associated disorders and requires extensive modulation of epithelial cell surface structures. Hence, the complex network of controlled proteolysis which facilitates tissue homeostasis in healthy individuals is deregulated and crucially contributes to the induction and progression of gastric cancer through processing of extracellular matrix (ECM) proteins, cell surface receptors, membrane-bound cytokines, and lateral adhesion molecules. Here, we summarize the recent reports on mechanisms how H. pylori utilizes a variety of extracellular proteases, involving the proteases Hp0169 and high temperature requirement A (HtrA) of bacterial origin, and host matrix-metalloproteinases (MMPs), a disintegrin and metalloproteinases (ADAMs) and tissue inhibitors of metalloproteinases (TIMPs). H. pylori-regulated proteases represent predictive biomarkers and attractive targets for therapeutic interventions in gastric cancer.

Helicobacter pylori-elicited induction in gastric mucosal matrix metalloproteinase-9 (MMP-9) release involves ERK-dependent cPLA2 activation and its recruitment to the membrane-localized Rac1/p38 complex

Matrix metalloproteinases (MMPs) are a family of endopeptidases implicated in a wide rage of degenerative and inflammatory diseases, including Helicobacter pylori-associated gastritis, and gastric and duodenal ulcer. As gastric mucosal inflammatory responses to H. pylori are characterized by the rise in MMP-9 production, as well as the induction in mitogen-activated protein kinase (MAPK) and Rac1 activation, we investigated the role of Rac1/MAPK in the processes associated with the release of MMP-9. We show that H. pylori LPS-elicited induction in gastric mucosal MMP-9 release is associated with MAPK, ERK and p38 activation, and occurs with the involvement of Rac1 and cytosolic phospholipase A2 (cPLA2). Further, we demonstrate that the LPS-induced MMP-9 release requires ERK-mediated phosphorylation of cPLA2 on Ser(505) that is essential for its membrane localization with Rac1, and that this process necessitates p38 participation. Moreover, we reveal that the activation and membrane translocation of p38 to the Rac1-GTP complex plays a pivotal role in cPLA2-dependent enhancement in MMP-9 release. Hence, our findings provide a strong evidence for the role of ERK/cPLA2 and Rac1/p38/cPLA2 cascade in H. pylori LPS-induced up-regulation in gastric mucosal MMP-9 release.

MMP2 and MMP7 at the invasive front of gastric cancer are not associated with mTOR expression

Background

Regulation of MMP expression by activation of mTOR signalling has been demonstrated for several tumor types, but has thus far not been confirmed in gastric cancer.

Findings

The study compromised 128 patients who underwent gastric resection for cancer (66.4 % male; 86 intestinal, 42 diffuse type). Immunohistochemical staining of MMPs was performed to analyse the topographical pattern of MMP expression at the tumor center and the invasive front, respectively. MMP2 showed higher expression at the invasive front compared to the tumor center, whereas MMP7 staining scores were higher in the tumor center, and there was no difference for MMP9. The expression of p-mTOR was higher in the tumor center than at the invasive front, with a similar trend for mTOR. For intestinal type gastric cancer there was a weak correlation of MMP9 with expression of mTOR in the tumor center. Otherwise, there was no correlation of the MMPs with mTOR. By treatment of MKN45 gastric cancer cells with rapamycin, a reduction of p-mTOR in the Western blot was achieved; however, expression of MMPs remained unaffected.

Conclusions

Expression of MMP2 and MMP7 in gastric cancer is not associated with mTOR, MMP9 expression might be related to mTOR signalling in a subset of tumors.

Electronic supplementary material

The online version of this article (doi:10.1186/s13000-015-0449-z) contains supplementary material, which is available to authorized users.

Helicobacter pylori CagA protein induces factors involved in the epithelial to mesenchymal transition (EMT) in infected gastric epithelial cells in an EPIYA- phosphorylation-dependent manner

As a result of Helicobacter pylori adhesion to gastric epithelial cells, the bacterial effector cytotoxin-associated gene A (CagA) is translocated intracellularly, and after hierarchical tyrosine phosphorylation on multiple EPIYA motifs, de-regulates cellular polarity and contributes to induction of an elongation and scattering phenotype that resembles the epithelial to mesenchymal transition (EMT). Stromelysin-1/matrix metalloproteinase-3 (MMP-3) has been reported to induce a sequence of molecular alterations leading to stable EMT transition and carcinogenesis in epithelial cells. To identify the putative role of CagA protein in MMP-3 induction, we exploited an experimental H. pylori infection system in gastric epithelial cell lines. We utilized isogenic mutants expressing CagA protein with variable numbers of EPIYA and phosphorylation-deficient EPIFA motifs, as well as cagA knockout and translocation-deficient cagE knockout strains. Increased levels of MMP-3 transcriptional activation were demonstrated by quantitative real time-PCR for strains with more than two terminal EPIYA phosphorylation motifs in CagA. MMP-3 expression in total cell lysates and the corresponding culture supernatants was associated with CagA expression and translocation and was dependent on CagA phosphorylation. A CagA EPIYA phosphorylation-dependent increase in gelatinase and caseinolytic activity was also detected in culture supernatants by zymography. A significant increase in the transcriptional activity of the mesenchymal markers Vimentin, Snail and ZEB1 and the stem cell marker CD44 was observed in the case of CagA containing phosphorylation-functional EPIYA motifs. Our data suggest that CagA protein induces EMT through EPIYA phosphorylation-dependent up-regulation of MMP-3. Moreover, no significant increase in EMT and stem cell markers was observed following infection with H. pylori strains that cannot effectively translocate CagA protein.

Efficacy of some non-conventional herbal medications (sulforaphane, tanshinone IIA, and tetramethylpyrazine) in inducing neuroprotection in comparison with interleukin-10 after spinal cord injury: A meta-analysis

CONTEXT

Inflammation after spinal cord injury (SCI) may be responsible for further neural damages and therefore inhibition of inflammatory processes may exert a neuroprotection effect.

OBJECTIVES

To assess the efficacy of some non-conventional herbal medications including sulforaphane, tanshinone IIA, and tetramethylpyrazine in reducing inflammation and compare them with a known effective anti-inflammatory agent (interleukin-10 (IL-10)).

METHODS

We searched relevant articles in Ovid database, Medline (PubMed) EMBASE, Google Scholar, Cochrane, and Scopus up to June 2013. The efficacy of each treatment and study powers were compared using random effects model of meta-analysis. To our knowledge, no conflict of interest exists.

RESULTS

Eighteen articles entered into the study. The meta-analysis revealed that exogenous IL-10 was more effective in comparison with the mentioned herbal extracts. The proposed pathways for each medication's effect on reducing the inflammation process are complex and many overlaps may exist.

CONCLUSION

IL-10 has a strong effect in the induction of neuroprotection and neurorecovery after SCI by multiple pathways. Tetramethylpyrazine has an acceptable influence in reducing inflammation through the up-regulation of IL-10. Outcomes of sulforaphane and tanshinone IIA administration are acceptable but still weaker than IL-10.

Helicobacter pylori induces cell migration and invasion through casein kinase 2 in gastric epithelial cells

BACKGROUND

Chronic infection with Helicobacter pylori (H. pylori) is causally linked with gastric carcinogenesis. Virulent H. pylori strains deliver bacterial CagA into gastric epithelial cells. Induction of high motility and an elongated phenotype is considered to be CagA-dependent process. Casein kinase 2 plays a critical role in carcinogenesis through signaling pathways related to the epithelial mesenchymal transition. This study was aimed to investigate the effect of H. pylori infection on the casein kinase 2-mediated migration and invasion in gastric epithelial cells.

MATERIALS AND METHODS

AGS or MKN28 cells as human gastric epithelial cells and H. pylori strains Hp60190 (ATCC 49503, CagA(+)) and Hp8822 (CagA(-)) were used. Cells were infected with H. pylori at multiplicity of infection of 100 : 1 for various times. We measured in vitro kinase assay to examine casein kinase 2 activity and performed immunofluorescent staining to observe E-cadherin complex. We also examined β-catenin transactivation through promoter assay and MMP7 expression by real-time PCR and ELISA.

RESULTS

H. pylori upregulates casein kinase 2 activity and inhibition of casein kinase 2 in H. pylori-infected cells profoundly suppressed cell invasiveness and motility. We confirmed that casein kinase 2 mediates membranous α-catenin depletion through dissociation of the α-/β-catenin complex in H. pylori-infected cells. We also found that H. pylori induces β-catenin nuclear translocation and increases MMP7 expressions mediated through casein kinase 2.

CONCLUSIONS

We show for the first time that CagA(+) H. pylori upregulates cellular invasiveness and motility through casein kinase 2. The demonstration of a mechanistic interplay between H. pylori and casein kinase 2 provides important insights into the role of CagA(+) H. pylori in the gastric cancer invasion and metastasis.

NF-κB activation and severity of gastritis in Helicobacter pylori-infected children and adults

BACKGROUND

In contrast to adults, Helicobacter pylori gastritis in children is reported as milder and ulcer disease as uncommon, but unequivocal data are lacking.

OBJECTIVES

To compare the frequency of gastro-duodenal ulcers in children and adults as well as the proportion of Helicobacter pylori infection in these patients and to study the effect of chronological age on NF-κB activation and on severity of gastritis.

DESIGN

Patients referred in one pediatric and one adult facility for upper GI endoscopy were included. Gastric biopsies were obtained in consecutive Helicobacter pylori-infected patients and age-matched negative controls for immunohistochemistry and electrophoresis mobility shift assay. Three age groups were defined: younger than 8 years, 8-17 years, and adults.

RESULTS

Peptic ulcer disease was less frequent in children and less frequently associated with Helicobacter pylori infection. When comparing infected subjects to controls, densities of neutrophils and CD20 cells in the lamina propria increased in all age groups, CD3 cells increasing only in patients older than 8 years and CD8 cells only in adults. NF-κB-p65-positive cells were also increased only in infected adults as well as NF-κB-binding activity. A positive correlation was found between age and densities of neutrophils and CD3, but not of CD8 or CD20 cells.

CONCLUSION

Peptic ulcer disease was less frequent in children and less frequently caused by Helicobacter pylori infection. The different clinical outcome of the infection in children can be the consequence of the lower mucosal immune response.

The association between CD14-260C/T polymorphism and malignant tumor risk: a meta-analysis of 5,603 participants

The CD14-260C/T polymorphism has been implicated to be in association with malignant tumor. However, a number of studies have reported inconclusive results. The aim of this study was to investigate the relationship of CD14-260C/T polymorphism and malignant tumor risk by meta-analysis. A search was performed in PubMed, Embase, the Chinese Journals Full-text Database (CNKI), and Wanfang databases up to August 2013. Odds ratio (OR) and 95 % confidence interval (95 % CI) were used to assess the association. Statistical analysis was calculated by STATA 11.0 software. The polymorphism was identified from 11 articles (12 case-control studies), involving 2,660 cases and 2,943 controls. Overall, no significant association between CD14-260C/T polymorphism and malignant tumor risk was found in the dominant model (TT + TC vs. CC: OR = 0.86, 95 % CI = 0.67-1.11). In the subgroup analysis by malignant tumor types, we found that the heterozygote model (TC vs. CC) might reduce the risk of malignant tumor, especially hematological malignance and prostate cancer (OR = 0.67, 95 % CI = 0.47-0.95), but not associated with gastrointestinal cancer susceptibility. In the subgroup analysis by ethnicity, no significant associations were found among different ethnicities. The study suggested that CD14-260C/T polymorphism might be a protective factor for hematological malignance and prostate tumor susceptibility but not an independent risk factor for gastrointestinal cancer susceptibility. To further evaluate the association between the polymorphism and malignant tumor susceptibility, more studies involving thousands of patients are required.

Induction of premalignant host responses by cathepsin x/z-deficiency in Helicobacter pylori-infected mice

Helicobacter pylori are responsible for the induction of chronic gastric inflammation progressing to atrophy, metaplasia, and gastric cancer. The overexpression of Cathepsin X/Z (Ctsz) in H. pylori-infected mucosa and gastric cancer is mediated predominantly by an augmented migration of ctsz^−/−positive macrophages and the up-regulation of Ctsz in tumor epithelium. To explore the Ctsz-function in the context of chronic inflammation and the development of preneoplastic lesions, we used Ctsz-deficient mice in a H. pylori gastritis model. Ctsz^−/− and wild-type (wt) mice were infected with H. pylori strain SS1. The mice were sacrificed at 24, 36, and 50 weeks post infection (wpi). The stomach was removed, and gastric strips were snap-frozen or embedded and stained with H&E. Tissue sections were scored for epithelial lesions and inflammation. Ki-67 and F4/80 immunostaining were used to measure epithelial cell proliferation and macrophage infiltration, respectively. The upregulation of compensating cathepsins and cytokines were confirmed by Western blotting and quantitative RT-PCR. SS1-infected wt and ctsz^−/− mice showed strong inflammation, foveolar hyperplasia, atrophy, and cystically-dilated glands. However, at 50 wpi, ctsz^−/− mice developed significantly more severe spasmolytic polypeptide-expressing metaplasia (SPEM), showed enhanced epithelial proliferation, and higher levels of infiltrating macrophages. Induction of cytokines was higher and significantly prolonged in ctsz^−/− mice compared to wt. Ctsz deficiency supports H. pylori-dependent development of chronic gastritis up to metaplasia, indicating a protective, but not proteolytic, function of Ctsz in inflammatory gastric disease.

Chronic gastric ulceration causes matrix metalloproteinases-9 and -3 augmentation: alleviation by melatonin

Matrix metalloproteinases (MMPs) are a family of zinc-dependent enzymes capable of degradation of extracellular matrix (ECM) and key player in various inflammatory diseases. We investigated the regulation of MMPs in chronic gastric ulceration in mice. We generated chronic gastric ulcers in mice by indomethacin and examined the activity and expression of MMP-9 and -3 in stomach. Melatonin (N-acetyl-5-methoxytryptamine) treatment has also been applied to mice to characterize the changes in expression and activities of MMPs in gastric tissues. We observed significant upregulation of MMP-9 and -3 expressions and activities in stomach with increasing doses and duration of indomethacin that corroborated with increased activity of activator protein (AP)-1. Substantial damage in gastric epithelial layer was found during chronic ulceration. Melatonin suppressed MMP-9 and -3 expressions and activities during prevention and healing of chronic gastric ulcers. It also suppressed protein oxidation, lipid peroxidation and antioxidant enzymes. Additionally, expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-8 was significantly high in ulcerated stomachs while melatonin treatment blocked them to control level. We found elevated phosphorylation of extracellular-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK) during chronic gastric ulceration, which were significantly reversed by melatonin. Moreover, expression of NF-κB, c-fos and c-jun were inhibited by melatonin resulting down regulation of MMP-9 and -3 expressions. In summary, oxidative stress is preceded by chronic inflammation that enhances the expression of MMP-9 and -3, while melatonin arrests both of them via reduction of AP-1 activity during protection of ulcer.

Regulation of the g1/s transition in hepatocytes: involvement of the cyclin-dependent kinase cdk1 in the DNA replication

A singular feature of adult differentiated hepatocytes is their capacity to proliferate allowing liver regeneration. This review emphasizes the literature published over the last 20 years that established the most important pathways regulating the hepatocyte cell cycle. Our article also aimed at illustrating that many discoveries in this field benefited from the combined use of in vivo models of liver regeneration and in vitro models of primary cultures of human and rodent hepatocytes. Using these models, our laboratory has contributed to decipher the different steps of the progression into the G1 phase and the commitment to S phase of proliferating hepatocytes. We identified the mitogen dependent restriction point located at the two-thirds of the G1 phase and the concomitant expression and activation of both Cdk1 and Cdk2 at the G1/S transition. Furthermore, we demonstrated that these two Cdks contribute to the DNA replication. Finally, we provided strong evidences that Cdk1 expression and activation is correlated to extracellular matrix degradation upon stimulation by the pro-inflammatory cytokine TNFα leading to the identification of a new signaling pathway regulating Cdk1 expression at the G1/S transition. It also further confirms the well-orchestrated regulation of liver regeneration via multiple extracellular signals and pathways.

Rebamipide abolishes Helicobacter pylori CagA-induced phospholipase D1 expression via inhibition of NFκB and suppresses invasion of gastric cancer cells

Infection with cagA-positive Helicobacter pylori is a risk factor for the development of severe gastritis and gastric cancer (GC). CagA protein is injected into gastric epithelial cells and deregulates a variety of cellular signaling molecules. Phospholipase D (PLD) is elevated in many different types of human cancers and has been implicated as a critical factor in inflammation and carcinogenesis. In this study, we show that infection with cagA-positive H. pylori in GC cells significantly induces PLD1 expression via CagA-dependent activation of nuclear factor κB (NFκB). Interestingly, the level of PLD1 protein and IκBα phosphorylation is aberrantly upregulated in H. pylori-infected human GC tissues. Infection with cagA-positive H. pylori and expression of CagA enhanced the binding of NFκB to the PLD1 promoter, and two functional NFκB-binding sites were identified within the PLD1 promoter. Rebamipide, a mucosal-protective antiulcer agent, abolished H. pylori cagA-induced PLD1 expression via inhibition of binding of NFκB to the PLD1 promoter, and also inhibited PLD activity. Moreover, rebamipide suppressed H. pylori-induced matrix metalloproteinase-9, interleukin-8 and activation-induced cytidine deaminase expression as well as invasion of GC cells through downregulation of PLD1. Our data suggest that H. pylori cagA targets PLD1 for invasion of GC cells, and rebamipide might contribute to the antitumorigenic effect of GC cells via inhibition of the H. pylori cagA-NFκB-PLD1 signaling pathway.

Expressions of MMPs and TIMP-1 in gastric ulcers may differentiate H. pylori-infected from NSAID-related ulcers

Background. Two major causes of gastric ulcers are Helicobacter pylori (H. pylori) infection and nonsteroidal anti-inflammatory drug (NSAID) use. Aims. This study aimed to determine if there were different expressions of matrix metalloproteinases (MMPs) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) between H. pylori-infected and NSAID-related ulcers. Methods. The 126 gastric ulcer patients (H. pylori infected n = 46; NSAID related n = 30; combined with two factors n = 50) provided ulcer and nonulcer tissues for assessment of MMP-3, -7, and -9 and TIMP-1 expression by immunohistochemical staining. Results. Gastric ulcer tissues had significantly higher MMP-3, -7, and -9 and TIMP-1 expressions than nonulcer tissues (P < 0.05). H. pylori-infected gastric ulcers had even higher MMP-7, MMP-9, and TIMP-1 expressions in epithelial cells than NSAID-related gastric ulcers (P < 0.05). In patients with the two combined factors, gastric ulcers expressed similar proportions of antral ulcers and MMP-7 and MMP-9 intensities to NSAID-related gastric ulcers, but lower MMP-9 and TIMP-1 than H. pylori-infected gastric ulcers (P < 0.05). Conclusions. H. pylori-infected gastric ulcers express higher MMP-7, MMP-9, and TIMP-1 than NSAID-related ulcers. In patients with the two combined factors, ulcer location and MMP-7 and MMP-9 intensities are similar to NSAID use.