Alkaline Phosphatase Relieves Colitis in Obese Mice Subjected to Forced Exercise via Its Anti-Inflammatory and Intestinal Microbiota-Shaping Properties.

Intestinal alkaline phosphatase (IAP) is an enzyme that plays a protective role in the gut. This study investigated the effect of IAP treatment on experimental colitis in mice subjected to forced exercise on a high-fat diet. C57BL/6 mice with TNBS colitis were fed a high-fat diet and subjected to forced treadmill exercise with or without IAP treatment. Disease activity, oxidative stress, inflammatory cytokines, and gut microbiota were assessed. Forced exercise exacerbated colitis in obese mice, as evidenced by increased disease activity index (DAI), oxidative stress markers, and proinflammatory adipokines and cytokines. IAP treatment significantly reduced these effects and promoted the expression of barrier proteins in the colonic mucosa. Additionally, IAP treatment altered the gut microbiota composition, favoring beneficial Verrucomicrobiota and reducing pathogenic Clostridia and Odoribacter. IAP treatment ameliorates the worsening effect of forced exercise on murine colitis by attenuating oxidative stress, downregulating proinflammatory biomarkers, and modulating the gut microbiota. IAP warrants further investigation as a potential therapeutic strategy for ulcerative colitis.

Helicobacter pylori-activated fibroblasts as a silent partner in gastric cancer development.

The discovery of Helicobacter pylori (Hp) infection of gastric mucosa leading to active chronic gastritis, gastroduodenal ulcers, and MALT lymphoma laid the groundwork for understanding of the general relationship between chronic infection, inflammation, and cancer. Nevertheless, this sequence of events is still far from full understanding with new players and mediators being constantly identified. Originally, the Hp virulence factors affecting mainly gastric epithelium were proposed to contribute considerably to gastric inflammation, ulceration, and cancer. Furthermore, it has been shown that Hp possesses the ability to penetrate the mucus layer and directly interact with stroma components including fibroblasts and myofibroblasts. These cells, which are the source of biophysical and biochemical signals providing the proper balance between cell proliferation and differentiation within gastric epithelial stem cell compartment, when exposed to Hp, can convert into cancer-associated fibroblast (CAF) phenotype. The crosstalk between fibroblasts and myofibroblasts with gastric epithelial cells including stem/progenitor cell niche involves several pathways mediated by non-coding RNAs, Wnt, BMP, TGF-ß, and Notch signaling ligands. The current review concentrates on the consequences of Hp-induced increase in gastric fibroblast and myofibroblast number, and their activation towards CAFs with the emphasis to the altered communication between mesenchymal and epithelial cell compartment, which may lead to inflammation, epithelial stem cell overproliferation, disturbed differentiation, and gradual gastric cancer development. Thus, Hp-activated fibroblasts may constitute the target for anti-cancer treatment and, importantly, for the pharmacotherapies diminishing their activation particularly at the early stages of Hp infection.

The Importance of Nutritional Aspects in the Assessment of Inflammation and Intestinal Barrier in Patients with Inflammatory Bowel Disease.

Intestinal inflammation in inflammatory bowel disease (IBD) is closely linked to nutrition. This study aimed to evaluate associations between nutritional, inflammatory, and intestinal barrier parameters in patients with IBD. We assessed nutritional status, fecal short-chain fatty acid profile, serum cytokine levels, and mRNA expression of enzymes and tight junction proteins in intestinal biopsies obtained from 35 patients, including 11 patients with inactive IBD, 18 patients with active IBD, and six controls. Patients with active IBD were characterized by hypoalbuminemia, fluctuations in body weight, and restriction of fiber-containing foods. In addition, they had significantly reduced levels of isovaleric acid and tended to have lower levels of butyric, acetic, and propionic acids. Patients with active IBD had higher mRNA expression of peroxisome proliferator-activated receptor γ and inducible nitric oxide synthase, and lower mRNA expression of claudin-2 and zonula occludens-1, compared with patients with inactive IBD. Moreover, patients with a body mass index (BMI) of ≥25 kg/m2 had higher median tumor necrosis factor-α levels that those with a lower BMI. We comprehensively evaluated inflammatory parameters in relation to IBD activity and nutritional status. The discrepancies between proinflammatory and anti-inflammatory parameters depending on IBD activity may be related to nutritional factors, including diet and abnormal body weight.

Application of the Clustering Technique to Multiple Nutritional Factors Related to Inflammation and Disease Progression in Patients with Inflammatory Bowel Disease.

Diet and nutritional status affect intestinal inflammation in patients with inflammatory bowel disease (IBD). The aim of this study was to use a cluster analysis to assess structural similarity between different groups of parameters including short-chain fatty acid (SCFA) levels in stool as well as hematological and inflammatory parameters (such as serum C-reactive protein (CRP) and proinflammatory and anti-inflammatory cytokines). We also assessed similarity between IBD patients in terms of various biochemical features of disease activity and nutritional status. A total of 48 participants were enrolled, including 36 patients with IBD and 12 controls. We identified four main meaningful clusters of parameters. The first cluster included all SCFAs with strong mutual correlations. The second cluster contained red blood cell parameters and albumin levels. The third cluster included proinflammatory parameters such as tumor necrosis factor-α, CRP, platelets, and phosphoric, succinic, and lactic acids. The final cluster revealed an association between zonulin and interleukins IL-10, IL-17, and IL-22. Moreover, we observed an inverse correlation between IL-6 and body mass index. Our findings suggest a link between nutritional status, diet, and inflammatory parameters in patients with IBD, which contribute to a better adjustment of the nutritional treatment.

Association between fecal levels of Short-Chain Fatty Acids and serum Pro- and Anti-Inflammatory Cytokines in patients with Inflammatory Bowel Disease.

INTRODUCTION: Inflammatory bowel disease (IBD) represents a group of chronic inflammatory disorders characterized by dysbiosis and altered short-chain fatty acid (SCFA) level. The association between individual SCFA levels and cytokine levels is unknown. OBJECTIVES: We aimed to determine the fecal SCFA levels in patients with IBD in relation to disease severity and the serum levels of pro- and anti-inflammatory cytokines. PATIENTS AND METHODS: The study included 61 patients with IBD (inactive, 22; active, 39) and 16 controls. Fecal levels of organic acids (acetic, lactic, propionic, butyric, isovaleric, isobutyric, and valeric), serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), IL-17, and IL-22, complete blood count and C-reactive protein (CRP) were measured. RESULTS: Patients with active IBD had reduced butyric, acetic, valeric, and isovaleric acid levels and elevated lactic acid levels in stool. Hemoglobin levels were positively correlated with the levels of acetic and butyric acids (R = 0.266 and R = 0.346, respectively; P <0.05). In addition, CRP levels were inversely correlated with butyric acid levels (R = -0.573; P <0.05). Higher serum TNF-α levels were observed in patients with active IBD compared with controls (6.64 pg/ml vs 2.05 pg/ml, P <0.05). No relationship was noted between the SCFA profile and cytokine levels. CONCLUSIONS: The study showed that determination of SCFA levels can be used to evaluate the activity of IBD. The relationship between individual SCFA and cytokine levels seems to be complex and requires further studies.

Time-extended exposure of gastric epithelial cells to secretome of Helicobacter pylori-activated fibroblasts induces reprogramming of gastric epithelium towards pre-cancerogenic and pro-invasive phenotype.

Despite of the improvement in gastric cancer (GC) therapies patients still suffer from cancer recurrence and metastasis. Recently, the high ratio of these events combined with increased chemoresistance has been related to the asymptomatic Helicobacter pylori (Hp) infections. The limited efficiency of GC treatment strategies is also increasingly attributed to the activity of tumor stroma with the key role of cancer-associated fibroblasts (CAFs). In order to investigate the influence of Hp infection within stromal gastric tissue on cancer initiation and progression, we have exposed normal gastric epithelial cells to long-term influence of Hp-activated gastric fibroblast secretome. We have referred obtained results to this secretome influence on cancer cell lines. The invasive properties of cells were checked by time-lapse video microscopy and basement membrane assays. The expression of invasion-related factors was checked by RT-PCR, Western Blot, immunofluorescence and Elisa. Hp-activated gastric fibroblast secretome induced EMT type 3-related shifts of RGM1 cell phenotype; in particular it augmented their motility, cytoskeletal plasticity and invasiveness. These effects were accompanied by Snail1/Twist activation, the up-regulation of cytokeratin19/FAP/TNC/Integrin-ß1 and MMPs, and by the induction of cMethigh/pEGFRhigh phenotype. Mechanistic studies suggest that this microevolution next to TGFß relies also on c-Met/EGFR signaling interplay and engages HGF-Integrin-Ras-dependent Twist activation leading to MMP and TNC upregulation with subsequent positive auto- and paracrine feedback loops intensifying this process. Similar shifts were detected in cancer cells exposed to this secretome. Collectively, we show that the secretome of Hp-infected fibroblasts induces reprogramming/microevolution of epithelial and cancer cells towards type 3 EMT-related invasive phenotype in a manner reciprocally reliant next to TGFß on cMet/Integrin-ß1/p-EGFR-dependent axis. Apparently, the phenotypical plasticity of Hp-activated fibroblast reprogrammed gastric epithelial cells determines their susceptibility to the pro-invasive signaling, which results in re-organization of gastric niches and provides the cues for GC promotion/progression.

Intestinal Alkaline Phosphatase Combined with Voluntary Physical Activity Alleviates Experimental Colitis in Obese Mice. Involvement of Oxidative Stress, Myokines, Adipokines and Proinflammatory Biomarkers.

Intestinal alkaline phosphatase (IAP) is an essential mucosal defense factor involved in the process of maintenance of gut homeostasis. We determined the effect of moderate exercise (voluntary wheel running) with or without treatment with IAP on the course of experimental murine 2,4,6-trinitrobenzenesulfonic acid (TNBS) colitis by assessing disease activity index (DAI), colonic blood flow (CBF), plasma myokine irisin levels and the colonic and adipose tissue expression of proinflammatory cytokines, markers of oxidative stress (SOD2, GPx) and adipokines in mice fed a standard diet (SD) or high-fat diet (HFD). Macroscopic and microscopic colitis in sedentary SD mice was accompanied by a significant decrease in CBF, and a significant increase in the colonic expression of tumor necrosis factor-alpha (TNF-α), IL-6, IL-1ß and leptin mRNAs and decrease in the mRNA expression of adiponectin. These effects were aggravated in sedentary HFD mice but reduced in exercising animals, potentiated by concomitant treatment with IAP, especially in obese mice. Exercising HFD mice demonstrated a substantial increase in the mRNA for adiponectin and a decrease in mRNA leptin expression in intestinal mucosa and mesenteric fat as compared to sedentary animals. The expression of SOD2 and GPx mRNAs was significantly decreased in adipose tissue in HFD mice, but these effects were reversed in exercising mice with IAP administration. Our study shows for the first time that the combination of voluntary exercise and oral IAP treatment synergistically favored healing of intestinal inflammation, strengthened the antioxidant defense and ameliorated the course of experimental colitis; thus, IAP may represent a novel adjuvant therapy to alleviate inflammatory bowel disease (IBD) in humans.

Effect of Acute Sprint Exercise on Myokines and Food Intake Hormones in Young Healthy Men.

Physical exercise is known to influence hormonal mediators of appetite, but the effect of short-term maximal intensity exercise on plasma levels of appetite hormones and cytokines has been little studied. We investigated the effect of a 30 s Wingate Test, followed by a postprandial period, on appetite sensations, food intake, and appetite hormones. Twenty-six physically active young males rated their subjective feelings of hunger, prospective food consumption, and fatigue on visual analogue scales at baseline, after exercise was completed, and during the postprandial period. Blood samples were obtained for the measurement of nesfatin-1, ghrelin, leptin, insulin, pancreatic polypeptide (PP), human growth factor (hGH) and cytokine interleukin-6 (IL-6), irisin and plasma lactate concentrations, at 30 min before exercise, immediately (210 s) after exercise, and 30 min following a meal and at corresponding times in control sedentary males without ad libitum meal intake, respectively. Appetite perceptions and food intake were decreased in response to exercise. Plasma levels of irisin, IL-6, lactate, nesfatin-1 and ghrelin was increased after exercise and then it was returned to postprandial/control period in both groups. A significant rise in plasma insulin, hGH and PP levels after exercise was observed while meal intake potentiated this response. In conclusion, an acute short-term fatiguing exercise can transiently suppress hunger sensations and food intake in humans. We postulate that this physiological response involves exercise-induced alterations in plasma hormones and the release of myokines such as irisin and IL-6, and supports the notion of existence of the skeletal muscle-brain-gut axis. Nevertheless, the detailed relationship between acute exercise releasing myokines, appetite sensations and impairment of this axis leading to several diseases should be further examined.

Long-Term Helicobacter pylori Infection Switches Gastric Epithelium Reprogramming Towards Cancer Stem Cell-Related Differentiation Program in Hp-Activated Gastric Fibroblast-TGFß Dependent Manner.

Helicobacter pylori (Hp)-induced inflammatory reaction leads to a persistent disturbance of gastric mucosa and chronic gastritis evidenced by deregulation of tissue self-renewal and local fibrosis with the crucial role of epithelial-mesenchymal transition (EMT) in this process. As we reported before, Hp activated gastric fibroblasts into cells possessing cancer-associated fibroblast properties (CAFs), which secreted factors responsible for EMT process initiation in normal gastric epithelial RGM1 cells. Here, we showed that the long-term incubation of RGM1 cells in the presence of Hp-activated gastric fibroblast (Hp-AGF) secretome induced their shift towards plastic LGR5+/Oct4high/Sox-2high/c-Mychigh/Klf4low phenotype (l.t.EMT+RGM1 cells), while Hp-non-infected gastric fibroblast (GF) secretome prompted a permanent epithelial-myofibroblast transition (EMyoT) of RGM1 cells favoring LGR-/Oct4high/Sox2low/c-Myclow/Klf4high phenotype (l.t.EMT-RGM1 cells). TGFß1 rich secretome from Hp-reprogrammed fibroblasts prompted phenotypic plasticity and EMT of gastric epithelium, inducing pro-neoplastic expansion of post-EMT cells in the presence of low TGFßR1 and TGFßR2 activity. In turn, TGFßR1 activity along with GF-induced TGFßR2 activation in l.t.EMT-RGM1 cells prompted their stromal phenotype. Collectively, our data show that infected and non-infected gastric fibroblast secretome induces alternative differentiation programs in gastric epithelium at least partially dependent on TGFß signaling. Hp infection-activated fibroblasts can switch gastric epithelium microevolution towards cancer stem cell-related differentiation program that can potentially initiate gastric neoplasm.

Alternative Therapy in the Prevention of Experimental and Clinical Inflammatory Bowel Disease. Impact of Regular Physical Activity, Intestinal Alkaline Phosphatase and Herbal Products.

Inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease, are multifactorial, chronic, disabling, and progressive diseases characterised by cyclical nature, alternating between active and quiescent states. While the aetiology of IBD is not fully understood, this complex of diseases involve a combination of factors including the genetic predisposition and changes in microbiome as well as environmental risk factors such as high-fat and low-fibre diets, reduced physical activity, air pollution and exposure to various toxins and drugs such as antibiotics. The prevalence of both IBD and obesity is increasing in parallel, undoubtedly proving the existing interactions between these risk factors common to both disorders to unravel poorly recognized cell signaling and molecular alterations leading to human IBD. Therefore, there is still a significant and unmet need for supportive and adjunctive therapy for IBD patients directed against the negative consequences of visceral obesity and bacterial dysbiosis. Among the alternative therapies, a moderate-intensity exercise can benefit the health and well-being of IBD patients and improve both the healing of human IBD and experimental animal colitis. Intestinal alkaline phosphatase (IAP) plays an essential role in the maintenance of intestinal homeostasis intestinal and the mechanism of mucosal defence. The administration of exogenous IAP could be recommended as a therapeutic strategy for the cure of diseases resulting from the intestinal barrier dysfunction such as IBD. Curcumin, a natural anti-inflammatory agent, which is capable of stimulating the synthesis of endogenous IAP, represents another alternative approach in the treatment of IBD. This review was designed to discuss potential "nonpharmacological" alternative and supplementary therapeutic approaches taking into account epidemiological and pathophysiological links between obesity and IBD, including changes in the functional parameters of the intestinal mucosa and alterations in the intestinal microbiome.

Interaction of epidermal growth factor with COX-2 products and peroxisome proliferator-activated receptor-γ system in experimental rat Barrett's esophagus.

Mixed acidic-alkaline refluxate is a major pathogenic factor in chronic esophagitis progressing to Barrett's esophagus (BE). We hypothesized that epidermal growth factor (EGF) can interact with COX-2 and peroxisome proliferator-activated receptor-γ (PPARγ) in rats surgically prepared with esophagogastroduodenal anastomosis (EGDA) with healthy or removed salivary glands to deplete salivary EGF. EGDA rats were treated with 1) vehicle, 2) EGF or PPARγ agonist pioglitazone with or without EGFR kinase inhibitor tyrphostin A46, EGF or PPARγ antagonist GW9662 respectively, 3) ranitidine or pantoprazole, and 4) the selective COX-2 inhibitor celecoxib combined with pioglitazone. At 3 mo, the esophageal damage and the esophageal blood flow (EBF) were determined, the mucosal expression of EGF, EGFR, COX-2, TNFα, and PPARγ mRNA and phospho-EGFR/EGFR protein was analyzed. All EGDA rats developed chronic esophagitis, esophageal ulcerations, and intestinal metaplasia followed by a fall in the EBF, an increase in the plasma of IL-1ß, TNFα, and mucosal PGE2 content, the overexpression of COX-2-, and EGF-EGFR mRNAs, and proteins, and these effects were aggravated by EGF and attenuated by pioglitazone. The rise in EGF and COX-2 mRNA was inhibited by pioglitazone but reversed by pioglitazone cotreated with GW9662. We conclude that 1) EGF can interact with PG/COX-2 and the PPARγ system in the mechanism of chronic esophagitis; 2) the deleterious effect of EGF involves an impairment of EBF and the overexpression of COX-2 and EGFR, and 3) agonists of PPARγ and inhibitors of EGFR may be useful in the treatment of chronic esophagitis progressing to BE.NEW & NOTEWORTHY Rats with EGDA exhibited chronic esophagitis accompanied by a fall in EBF and an increase in mucosal expression of mRNAs for EGF, COX-2, and TNFα, and these effects were exacerbated by exogenous EGF and reduced by removal of a major source of endogenous EGF with salivectomy or concurrent treatment with tyrphostin A46 or pioglitazone combined with EGF. Beneficial effects of salivectomy in an experimental model of BE were counteracted by PPARγ antagonist, whereas selective COX-2 inhibitor celecoxib synergistically with pioglitazone reduced severity of esophageal damage and protected esophageal mucosa from reflux. We propose the cross talk among EGF/EGFR, PG/COX-2, and proinflammatory cytokines with PPARγ pathway in the mechanism of pathogenesis of chronic esophagitis progressing to BE and EAC.

Role of Obesity, Mesenteric Adipose Tissue, and Adipokines in Inflammatory Bowel Diseases.

Inflammatory bowel diseases (IBDs) are a group of disorders which include ulcerative colitis and Crohn's disease. Obesity is becoming increasingly more common among patients with inflammatory bowel disease and plays a role in the development and course of the disease. This is especially true in the case of Crohn's disease. The recent results indicate a special role of visceral adipose tissue and particularly mesenteric adipose tissue, also known as "creeping fat", in pathomechanism, leading to intestinal inflammation. The involvement of altered adipocyte function and the deregulated production of adipokines, such as leptin and adiponectin, has been suggested in pathogenesis of IBD. In this review, we discuss the epidemiology and pathophysiology of obesity in IBD, the influence of a Western diet on the course of Crohn's disease and colitis in IBD patients and animal's models, and the potential role of adipokines in these disorders. Since altered body composition, decrease of skeletal muscle mass, and development of pathologically changed mesenteric white adipose tissue are well-known features of IBD and especially of Crohn's disease, we discuss the possible crosstalk between adipokines and myokines released from skeletal muscle during exercise with moderate or forced intensity. The emerging role of microbiota and the antioxidative and anti-inflammatory enzymes such as intestinal alkaline phosphatase is also discussed, in order to open new avenues for the therapy against intestinal perturbations associated with IBD.

Effect of TLRs and nuclear PPARγ receptors on the mechanisms of intestinal carcinogenesis.

Tool Like Receptors (TLR) are transmembrane proteins that play an important role in immune reactions associated with the recognition of pathogenic factors that cause infection. However, chronic inflammatory conditions associated with the activation of these receptors create favorable conditions for the development of cancerous processes. The relationship between nuclear PPARγ receptors and TLR receptors is also important, whose role and importance in the process of carcinogenesis is the subject of various studies.

Helicobacter pylori-activated gastric fibroblasts induce epithelial-mesenchymal transition of gastric epithelial cells in vitro in a TGF-ß-dependent manner.

BACKGROUND: Colonization of the gastric mucosa with Helicobacter pylori (Hp) leads to the cascade of pathologic events including local inflammation, gastric ulceration, and adenocarcinoma formation. Paracrine loops between tissue cells and Hp contribute to the formation of gastric cancerous loci; however, the specific mechanisms underlying existence of these loops remain unknown. We determined the phenotypic properties of gastric fibroblasts exposed to Hp (cagA+vacA+) infection and their influence on normal epithelial RGM-1 cells. MATERIALS AND METHODS: RGM-1 cells were cultured in the media conditioned with Hp-activated gastric fibroblasts. Their morphology and phenotypical changes associated with epithelial-mesenchymal transition (EMT) were assessed by Nomarski and fluorescence microscopy and Western blot analysis. Motility pattern of RGM-1 cells was examined by time-lapse video microscopy and transwell migration assay. The content of TGF-ß in Hp-activated fibroblast-conditioned media was determined by ELISA. RESULTS: The supernatant from Hp-activated gastric fibroblasts caused the EMT-like phenotypic diversification of RGM-1 cells. The formation of fibroblastoid cell sub-populations, the disappearance of their collective migration, an increase in transmigration potential with downregulation of E-cadherin and upregulation of N-cadherin proteins, prominent stress fibers, and decreased proliferation were observed. The fibroblast (CAF)-like transition was manifested by increased secretome TGF-ß level, α-SMA protein expression, and its incorporation into stress fibers, and the TGF-ßR1 kinase inhibitor reduced the rise in Snail, Twist, and E-cadherin mRNA and increased E-cadherin expression induced by CAFs. CONCLUSION: Gastric fibroblasts which are one of the main targets for Hp infection contribute to the paracrine interactions between Hp, gastric fibroblasts, and epithelial cells. TGF-ß secreted by Hp-activated gastric fibroblasts prompting their differentiation toward CAF-like phenotype promotes the EMT-related phenotypic shifts in normal gastric epithelial cell populations. This mechanism may serve as the prerequisite for GC development.

Curcumin: A Potent Protectant against Esophageal and Gastric Disorders.

Turmeric obtained from the rhizomes of Curcuma longa has been used in the prevention and treatment of many diseases since the ancient times. Curcumin is the principal polyphenol isolated from turmeric, which exhibits anti-inflammatory, antioxidant, antiapoptotic, antitumor, and antimetastatic activities. The existing evidence indicates that curcumin can exert a wide range of beneficial pleiotropic properties in the gastrointestinal tract, such as protection against reflux esophagitis, Barrett's esophagus, and gastric mucosal damage induced by nonsteroidal anti-inflammatory drugs (NSAIDs) and necrotizing agents. The role of curcumin as an adjuvant in the treatment of a Helicobacter pylori infection in experimental animals and humans has recently been proposed. The evidence that this turmeric derivative inhibits the invasion and proliferation of gastric cancer cells is encouraging and warrants further experimental and clinical studies with newer formulations to support the inclusion of curcumin in cancer therapy regimens. This review was designed to analyze the existing data from in vitro and in vivo animal and human studies in order to highlight the mechanisms of therapeutic efficacy of curcumin in the protection and ulcer healing of the upper gastrointestinal tract, with a major focus on addressing the protection of the esophagus and stomach by this emerging compound.

Role of Helicobacter pylori infection in cancer-associated fibroblast-induced epithelial-mesenchymal transition in vitro.

BACKGROUND: Major human gastrointestinal pathogen Helicobacter pylori (H. pylori) colonizes the gastric mucosa causing inflammation and severe complications including cancer, but the involvement of fibroblasts in the pathogenesis of these disorders in H. pylori-infected stomach has been little studied. Normal stroma contains few fibroblasts, especially myofibroblasts. Their number rapidly increases in the reactive stroma surrounding inflammatory region and neoplastic tissue; however, the interaction between H. pylori and fibroblasts remains unknown. We determined the effect of coincubation of normal rat gastric fibroblasts with alive H. pylori (cagA+vacA+) and H. pylori (cagA-vacA-) strains on the differentiation of these fibroblasts into cells possessing characteristics of cancer-associated fibroblasts (CAFs) able to induce epithelial-mesenchymal transition (EMT) of normal rat gastric epithelial cells (RGM-1). MATERIALS AND METHODS: The panel of CAFs markers mRNA was analyzed in H. pylori (cagA+vacA+)-infected fibroblasts by RT-PCR. After insert coculture of differentiated fibroblasts with RGM-1 cells from 24 up to 48, 72, and 96 hours, the mRNA expression for EMT-associated genes was analyzed by RT-PCR. RESULTS: The mRNA expression for CAFs markers was significantly increased after 72 hours of infection with H. pylori (cagA+vacA+) but not H. pylori (cagA-vacA-) strain. Following coculture with CAFs, RGM-1 cells showed significant decrease in E-cadherin mRNA, and the parallel increase in the expression of Twist and Snail transcription factors mRNA was observed along with the overexpression of mRNAs for TGFßR, HGFR, FGFR, N-cadherin, vimentin, α-SMA, VEGF, and integrin-ß1. CONCLUSION: Helicobacter pylori (cagA+vacA+) strain induces differentiation of normal fibroblasts into CAFs, likely to initiate the EMT process in RGM-1 epithelial cell line.

Inhibitory effect of selenomethionine on carcinogenesis in the model of human colorectal cancer in vitro and its link to the Wnt/ß-catenin pathway.

Selenium compounds have been implicated as anticancer agents; however, the mechanism of their inhibitory action against cancer development has not been extensively investigated. A constitutive activation of the Wnt/ß-catenin pathway is a central event in colorectal carcinogenesis. In this pathway, excessive cell proliferation is initiated by generation of ß-catenin followed by overexpression of proto-oncogenes, such as c-Myc. It is believed that under physiological conditions the level of c-Myc is efficiently controlled by accessibility of the ß-catenin protein through the process of phosphorylation by glycogen synthase kinase 3ß (GSK-3ß). Here, we determined whether selenomethionine (SeMet) can inhibit cell growth and affect the Wnt/ß-catenin pathway in the HT-29 human colorectal cancer cells in vitro. The effective cytotoxic doses of SeMet have been selected after 48 h of incubation of this compound with colorectal cancer HT-29 cell line. MTT assay was used to assess cell viability and the protein and mRNA levels of ß-catenin and c-Myc were determined by Western blotting and qPCR, respectively. SeMet potently inhibited growth of HT-29 cells, significantly decreased level of the ß-catenin protein and mRNA concentration, down-regulated the c-Myc gene expression and up-regulated the pro-apoptotic Bax protein level. Moreover, SeMet increased the level of GSK-3ß phosphorylated at serine 9 (S9) and significantly increased the level of ß-catenin phosphorylated at S33 and S37. We conclude that SeMet suppresses growth of HT-29 colorectal cancer cells by a mechanism linked to the Wnt/ß-catenin pathway, however, degradation of ß-catenin may occur independently of GSK-3ß catalytic activity and its phosphorylation status.

Exploiting Significance of Physical Exercise in Prevention of Gastrointestinal Disorders.

BACKGROUND: Physical activity can be involved in the prevention of gastrointestinal (GI)-tract diseases, however, the results regarding the volume and the intensity of exercise considered as beneficial for protection of gastrointestinal organs are conflicting. AIMS AND METHODS: The main objective of this review is to provide a comprehensive and updated overview on the beneficial and harmful effects of physical activity on the gastrointestinal tract. We attempted to discuss recent evidence regarding the association between different modes and intensity levels of exercise and physiological functions of the gut and gut pathology. RESULTS: The regular, moderate exercise can exert a beneficial effect on GI-tract disorders such as reflux esophagitis, peptic ulcers, cholelithiasis, constipation and Inflammatory Bowel Disease (IBD) leading to the attenuation of the symptoms. This voluntary exercise has been shown to reduce the risk of colorectal cancer. On the other hand, there is considerable evidence that the high-intensity training or prolonged endurance training can exert a negative influence on GI-tract resulting in the exacerbation of symptoms. CONCLUSION: Physical activity can exhibit a beneficial effect on a variety of gastrointestinal diseases, however, this effect depends upon the exercise mode, duration and intensity. The accumulated evidence indicate that management of gastrointestinal problems and their relief by the exercise seems to be complicated and require adjustments of physical activity training, dietary measures and medical monitoring of symptoms. More experimental and clinical studies on the effects of physical activity on GI-tract disorders are warranted. Especially, the association between the exercise intensity and data addressing the underlying mechanism(s) of the exercise as the complementary therapy in the treatment of gastrointestinal disorders, require further determination in animal models and humans.

Mechanisms of curcumin-induced gastroprotection against ethanol-induced gastric mucosal lesions.

BACKGROUND: Curcumin, a pleiotropic substance used for centuries in traditional medicine, exhibits antioxidant, anti-inflammatory and antiproliferative efficacy against various tumours, but the role of curcumin in gastroprotection is little studied. We determined the effect of curcumin against gastric haemorrhagic lesions induced by 75% ethanol and alterations in gastric blood flow (GBF) in rats with cyclooxygenase-1 (COX-1) and COX-2 activity inhibited by indomethacin, SC-560 or rofecoxib, inhibited NO-synthase activity, capsaicin denervation and blockade of TRPV1 receptors by capsazepine. METHODS: One hour after ethanol administration, the gastric mucosal lesions were assessed by planimetry, the GBF was examined by H2 gas clearance, plasma gastrin was determined by radioimmunoassay, and the gastric mucosal mRNA expression of Cdx-2, HIF-1α, HO-1 and SOD 2 was analysed by RT-PCR. RESULTS: Curcumin, in a dose-dependent manner, reduced ethanol-induced gastric lesions and significantly increased GBF and plasma gastrin levels. Curcumin-induced protection was completely reversed by indomethacin and SC-560, and significantly attenuated by rofecoxib, L-NNA, capsaicin denervation and capsazepine. Curcumin downregulated Cdx-2 and Hif-1α mRNA expression and upregulated HO-1 and SOD 2, and these effects were reversed by L-NNA and further restored by co-treatment of L-NNA with L-arginine. CONCLUSIONS: Curcumin-induced protection against ethanol damage involves endogenous PG, NO, gastrin and CGRP released from sensory nerves due to activation of the vanilloid TRPV1 receptor. This protective effect can be attributed to the inhibition of HIF-1α and Cdx-2 expression and the activation of HO-1 and SOD 2 expression.

Intestinal parameters of oxidative imbalance in celiac adults with extraintestinal manifestations.

AIM: To evaluate selected intestinal parameters of oxidative stress, and antioxidant capacity in adult celiac disease patients with extraintestinal manifestations. METHODS: The study involved 85 adult patients divided into the following subgroups: (1) patients with newly diagnosed celiac disease (CD) (n = 7); (2) celiac patients not adhering to a gluten-free diet (GFD) (n = 22); (3) patients with CD on the GFD (n = 31); and (4) patients with functional disorders of the gastrointestinal tract, serving as controls (n = 25). Celiac patients presented with non-classic symptoms or extraintestinal manifestations. Standard blood tests including serum antioxidant levels (uric acid, bilirubin, and vitamin D), celiac antibody levels, and histopathological status of duodenal biopsy specimens have been determined. The expression of mRNA for tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), interleukin 10 (IL-10), superoxide dismutase (SOD), heat-shock protein 70 (HSP-70), hypoxia-inducible factor 1 (HIF-1α), and BAX in the duodenal mucosa of patients was analyzed by reverse transcriptase-polymerase chain reaction. RESULTS: The mean plasma uric acid level in patients with active CD (newly diagnosed and nonadherent patients) and treated celiac patients was significantly higher than in controls (260.17 ± 53.65 vs 190.8 ± 22.98, P < 0.001, and 261.7 ± 51.79 vs 190.8 ± 22.98, P < 0.001, respectively). The mean bilirubin concentration in active and treated celiac patients was significantly lower than in controls (8.23 ± 5.04 vs 10.48 ± 4.08, P < 0.05 and 8.06 ± 3.31 vs 10.48 ± 4.08, P < 0.05, respectively). The mean plasma vitamin D level was significantly lower in active celiac patients than in treated celiac patients and controls (19.37 ± 9.03 vs 25.15 ± 11.2, P < 0.05 and 19.37 ± 9.03 vs 29.67 ± 5.12, P < 0.001, respectively). The expression of TNF-α, IL-10, and HSP-70 mRNAs was significantly elevated in the celiac groups regardless of the diet when compared with controls. Patients on the GFD presented a significantly lower mRNA expression of TNF-α and IL-10 than in newly diagnosed and nonadherent patients (P < 0.05). The expression of SOD mRNA was significantly elevated in celiac patients compared with controls (P < 0.05), with a significant difference between treated and untreated patients (P < 0.05). The expression of HIF-1α mRNA and BAX mRNA was significantly higher in patients with active CD compared with controls and patients on GFD, while no difference was observed between the latter two groups. CONCLUSION: Increased intestinal expression of HSP-70 despite GFD indicates that GFD only partially reduced oxidative stress. CD patients exhibited an oxidative imbalance and inflammatory response despite GFD. Uric acid may act as an important antioxidant in CD.