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Sample records for alcohol-induced intestinal barrier

  1. THE ROLE OF MIR-212 AND INOS IN ALCOHOL-INDUCED INTESTINAL BARRIER DYSFUNCTION AND STEATOHEPATITIS

    PubMed Central

    Tang, Yueming; Zhang, Lijuan; Forsyth, Christopher B.; Shaikh, Maliha; Song, Shiwen; Keshavarzian, Ali

    2015-01-01

    Background Alcoholic liver disease (ALD) is commonly associated with intestinal barrier dysfunction. Alcohol-induced dysregulation of intestinal tight junction (TJ) proteins, such as Zonula Occludens-1 (ZO-1), plays an important role in alcohol-induced gut leakiness. However, the mechanism of alcohol-induced disruption of TJ proteins is not well established. The goal of this study was to elucidate this mechanism by studying the role of MicroRNA 212 (miR-212) and inducible nitric oxide synthase (iNOS) in alcohol-induced gut leakiness. Methods The permeability of the Caco-2 monolayer was assessed by transepithelial electrical resistance (TER) and flux of fluorescein sulfonic acid (FSA). miR-212 was measured by real time PCR. The wild type, iNOS knockout, and miR-212 knockdown mice were fed with alcohol diet (29% of total calories, 4.5% v/v) for 8 weeks. The LNA-anti-miR-212 was used to inhibit miR-212 expression in mice. The alcohol-induced intestinal permeability, miR-212 expression and liver injuries in mice were measured. Results Our in vitro monolayer and in vivo mice studies showed that: (1) alcohol-induced over-expression of the intestinal miR-212 and intestinal hyperpermeability is prevented by using miR-212 knock-down techniques; and (2). iNOS is upregulated in the intestine by alcohol and that iNOS signaling is required for alcohol-induced miR-212 over-expression, ZO-1 disruption, gut leakiness and steatohepatis. Conclusions These studies thus support a novel miR-212 mechanism for alcohol-induced gut leakiness and a potential target that could be exploited for therapeutic intervention to prevent leaky gut and liver injury in alcoholics. PMID:26207424

  2. Dietary fat sources differentially modulate intestinal barrier and hepatic inflammation in alcohol-induced liver injury in rats

    PubMed Central

    Zhong, Wei; Li, Qiong; Xie, Guoxiang; Sun, Xiuhua; Tan, Xiaobing; Sun, Xinguo; Jia, Wei

    2013-01-01

    Endotoxemia is a causal factor in the development of alcoholic liver injury. The present study aimed at determining the interactions of ethanol with different fat sources at the gut-liver axis. Male Sprague-Dawley rats were pair fed control or ethanol liquid diet for 8 wk. The liquid diets were based on a modified Lieber-DeCarli formula, with 30% total calories derived from corn oil (rich in polyunsaturated fatty acids). To test the effects of saturated fats, corn oil in the ethanol diet was replaced by either cocoa butter (CB, rich in long-chain saturated fatty acids) or medium-chain triglycerides (MCT, exclusively medium-chain saturated fatty acids). Ethanol feeding increased hepatic lipid accumulation and inflammatory cell infiltration and perturbed hepatic and serum metabolite profiles. Ethanol feeding with CB or MCT alleviated ethanol-induced liver injury and attenuated ethanol-induced metabolic perturbation. Both CB and MCT also normalized ethanol-induced hepatic macrophage activation, cytokine expression, and neutrophil infiltration. Ethanol feeding elevated serum endotoxin level, which was normalized by MCT but not CB. In accordance, ethanol-induced downregulations of intestinal occludin and zonula occludens-1 were normalized by MCT but not CB. However, CB normalized ethanol-increased hepatic endotoxin level in association with upregulation of an endotoxin detoxifying enzyme, argininosuccinate synthase 1 (ASS1). Knockdown ASS1 in H4IIEC3 cells resulted in impaired endotoxin clearance and upregulated cytokine expression. These data demonstrate that the protection of saturated fats against alcohol-induced liver injury occur via different actions at the gut-liver axis and are chain length dependent. PMID:24113767

  3. Lactobacillus rhamnosus GG culture supernatant ameliorates acute alcohol-induced intestinal permeability and liver injury

    PubMed Central

    Wang, Yuhua; Liu, Yanlong; Sidhu, Anju; Ma, Zhenhua; McClain, Craig

    2012-01-01

    Endotoxemia is a contributing cofactor to alcoholic liver disease (ALD), and alcohol-induced increased intestinal permeability is one of the mechanisms of endotoxin absorption. Probiotic bacteria have been shown to promote intestinal epithelial integrity and protect barrier function in inflammatory bowel disease (IBD) and in ALD. Although it is highly possible that some common molecules secreted by probiotics contribute to this action in IBD, the effect of probiotic culture supernatant has not yet been studied in ALD. We examined the effects of Lactobacillus rhamnosus GG culture supernatant (LGG-s) on the acute alcohol-induced intestinal integrity and liver injury in a mouse model. Mice on standard chow diet were supplemented with supernatant from LGG culture (109 colony-forming unit/mouse) for 5 days, and one dose of alcohol at 6 g/kg body wt was administered via gavage. Intestinal permeability was measured by FITC-FD-4 ex vivo. Alcohol-induced liver injury was examined by measuring the activity of alanine aminotransferase (ALT) in plasma, and liver steatosis was evaluated by triglyceride content and Oil Red O staining of the liver sections. LGG-s pretreatment restored alcohol-induced reduction in ileum mRNA levels of claudin-1, intestine trefoil factor (ITF), P-glycoprotein (P-gp), and cathelin-related antimicrobial peptide (CRAMP), which play important roles on intestinal barrier integrity. As a result, LGG-s pretreatment significantly inhibited the alcohol-induced intestinal permeability, endotoxemia and subsequently liver injury. Interestingly, LGG-s pretreatment increased ileum mRNA expression of hypoxia-inducible factor (HIF)-2α, an important transcription factor of ITF, P-gp, and CRAMP. These results suggest that LGG-s ameliorates the acute alcohol-induced liver injury by promoting HIF signaling, leading to the suppression of alcohol-induced increased intestinal permeability and endotoxemia. The use of bacteria-free LGG culture supernatant provides a novel

  4. Lactobacillus rhamnosus GG treatment potentiates intestinal hypoxia-inducible factor, promotes intestinal integrity and ameliorates alcohol-induced liver injury.

    PubMed

    Wang, Yuhua; Kirpich, Irina; Liu, Yanlong; Ma, Zhenhua; Barve, Shirish; McClain, Craig J; Feng, Wenke

    2011-12-01

    Gut-derived endotoxin is a critical factor in the development and progression of alcoholic liver disease (ALD). Probiotics can treat alcohol-induced liver injury associated with gut leakiness and endotoxemia in animal models, as well as in human ALD; however, the mechanism or mechanisms of their beneficial action are not well defined. We hypothesized that alcohol impairs the adaptive response-induced hypoxia-inducible factor (HIF) and that probiotic supplementation could attenuate this impairment, restoring barrier function in a mouse model of ALD by increasing HIF-responsive proteins (eg, intestinal trefoil factor) and reversing established ALD. C57BJ/6N mice were fed the Lieber DeCarli diet containing 5% alcohol for 8 weeks. Animals received Lactobacillus rhamnosus GG (LGG) supplementation in the last 2 weeks. LGG supplementation significantly reduced alcohol-induced endotoxemia and hepatic steatosis and improved liver function. LGG restored alcohol-induced reduction of HIF-2α and intestinal trefoil factor levels. In vitro studies using the Caco-2 cell culture model showed that the addition of LGG supernatant prevented alcohol-induced epithelial monolayer barrier dysfunction. Furthermore, gene silencing of HIF-1α/2α abolished the LGG effects, indicating that the protective effect of LGG is HIF-dependent. The present study provides a mechanistic insight for utilization of probiotics for the treatment of ALD, and suggests a critical role for intestinal hypoxia and decreased trefoil factor in the development of ALD. PMID:22093263

  5. Disruption of the Circadian Clock in Mice Increases Intestinal Permeability and Promotes Alcohol-Induced Hepatic Pathology and Inflammation

    PubMed Central

    Forsyth, Christopher B.; Shaikh, Maliha; Cavanaugh, Kate; Tang, Yueming; Vitaterna, Martha Hotz; Song, Shiwen

    2013-01-01

    The circadian clock orchestrates temporal patterns of physiology and behavior relative to the environmental light:dark cycle by generating and organizing transcriptional and biochemical rhythms in cells and tissues throughout the body. Circadian clock genes have been shown to regulate the physiology and function of the gastrointestinal tract. Disruption of the intestinal epithelial barrier enables the translocation of proinflammatory bacterial products, such as endotoxin, across the intestinal wall and into systemic circulation; a process that has been linked to pathologic inflammatory states associated with metabolic, hepatic, cardiovascular and neurodegenerative diseases – many of which are commonly reported in shift workers. Here we report, for the first time, that circadian disorganization, using independent genetic and environmental strategies, increases permeability of the intestinal epithelial barrier (i.e., gut leakiness) in mice. Utilizing chronic alcohol consumption as a well-established model of induced intestinal hyperpermeability, we also found that both genetic and environmental circadian disruption promote alcohol-induced gut leakiness, endotoxemia and steatohepatitis, possibly through a mechanism involving the tight junction protein occludin. Circadian organization thus appears critical for the maintenance of intestinal barrier integrity, especially in the context of injurious agents, such as alcohol. Circadian disruption may therefore represent a previously unrecognized risk factor underlying the susceptibility to or development of alcoholic liver disease, as well as other conditions associated with intestinal hyperpermeability and an endotoxin-triggered inflammatory state. PMID:23825629

  6. Lactobacillus GG treatment ameliorates alcohol-induced intestinal oxidative stress, gut leakiness, and liver injury in a rat model of alcoholic steatohepatitis.

    PubMed

    Forsyth, Christopher B; Farhadi, Ashkan; Jakate, Shriram M; Tang, Yueming; Shaikh, Maliha; Keshavarzian, Ali

    2009-03-01

    Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent and treat diseases associated with gut-derived bacterial products and disorders associated with gut leakiness. Indeed, "probiotic"Lactobacillus rhamnosus has been successfully used to treat alcohol-induced liver injury in rats. However, the mechanism of action involved in the potential beneficial effects of L. rhamnosus in alcohol liver injury is not known. We hypothesized that probiotics could preserve normal barrier function in an animal model of ALD by preventing alcohol-induced oxidative stress and thus prevent the development of hyperpermeability and subsequent alcoholic steatohepatitis (ASH). Male Sprague-Dawley rats were gavaged with alcohol twice daily (8 gm/kg) for 10 weeks. In addition, alcoholic rats were also treated with once daily gavage of either 2.5 x 10(7) live L. rhamnosus Gorbach-Goldin (LGG) or vehicle (V). Intestinal permeability (baseline and at 10 weeks) was determined using a sugar bolus and GC analysis of urinary sugars. Intestinal and liver tissues were analyzed for markers of oxidative stress and inflammation. In addition, livers were assessed histologically for severity of ASH and total fat (steatosis). Alcohol+LGG (ALC+LGG)-fed rats had significantly (P< or =.05) less severe ASH than ALC+V-fed rats. L. rhamnosus Gorbach-Goldin also reduced alcohol-induced gut leakiness and significantly blunted alcohol-induced oxidative stress and inflammation in both intestine and the liver. L. rhamnosus Gorbach-Goldin probiotic gavage significantly ameliorated ASH in rats. This improvement was associated with reduced markers of intestinal and liver

  7. Night workers with circadian misalignment are susceptible to alcohol-induced intestinal hyperpermeability with social drinking.

    PubMed

    Swanson, Garth R; Gorenz, Annika; Shaikh, Maliha; Desai, Vishal; Kaminsky, Thomas; Van Den Berg, Jolice; Murphy, Terrence; Raeisi, Shohreh; Fogg, Louis; Vitaterna, Martha Hotz; Forsyth, Christopher; Turek, Fred; Burgess, Helen J; Keshavarzian, Ali

    2016-07-01

    Alcohol-induced intestinal hyperpermeability (AIHP) is a known risk factor for alcoholic liver disease (ALD), but only 20-30% of heavy alcoholics develop AIHP and ALD. The hypothesis of this study is that circadian misalignment would promote AIHP. We studied two groups of healthy subjects on a stable work schedule for 3 mo [day workers (DW) and night workers (NW)]. Subjects underwent two circadian phase assessments with sugar challenge to access intestinal permeability between which they drank 0.5 g/kg alcohol daily for 7 days. Sleep architecture by actigraphy did not differ at baseline or after alcohol between either group. After alcohol, the dim light melatonin onset (DLMO) in the DW group did not change significantly, but in the NW group there was a significant 2-h phase delay. Both the NW and DW groups had no change in small bowel permeability with alcohol, but only in the NW group was there an increase in colonic and whole gut permeability. A lower area under the curve of melatonin inversely correlated with increased colonic permeability. Alcohol also altered peripheral clock gene amplitude of peripheral blood mononuclear cells in CLOCK, BMAL, PER1, CRY1, and CRY2 in both groups, and inflammatory markers lipopolysaccharide-binding protein, LPS, and IL-6 had an elevated mesor at baseline in NW vs. DW and became arrhythmic with alcohol consumption. Together, our data suggest that central circadian misalignment is a previously unappreciated risk factor for AIHP and that night workers may be at increased risk for developing liver injury with alcohol consumption. PMID:27198191

  8. Epidermal Growth Factor and Intestinal Barrier Function.

    PubMed

    Tang, Xiaopeng; Liu, Hu; Yang, Shufen; Li, Zuohua; Zhong, Jinfeng; Fang, Rejun

    2016-01-01

    Epidermal growth factor (EGF) is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health. PMID:27524860

  9. Epidermal Growth Factor and Intestinal Barrier Function

    PubMed Central

    Liu, Hu; Yang, Shufen; Li, Zuohua; Zhong, Jinfeng

    2016-01-01

    Epidermal growth factor (EGF) is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health. PMID:27524860

  10. Intestinal barrier: Molecular pathways and modifiers.

    PubMed

    Jeon, Min Kyung; Klaus, Christina; Kaemmerer, Elke; Gassler, Nikolaus

    2013-11-15

    The gastrointestinal tract is frequently challenged by pathogens/antigens contained in food and water and the intestinal epithelium must be capable of rapid regeneration in the event of tissue damage. Disruption of the intestinal barrier leads to a number of immune-mediated diseases, including inflammatory bowel disease, food allergy, and celiac disease. The intestinal mucosa is composed of different types of epithelial cells in specific barrier functions. Epithelial cells control surface-associated bacterial populations without disrupting the intestinal microflora that is crucial for host health. They are also capable of modulating mucosal immune system, and are thus essential in maintaining homeostasis in the gut. Thus, the regulation of intestinal epithelial homeostasis is crucial for the maintenance of the structure of the mucosa and the defensive barrier functions. Recent studies have demonstrated that multiple molecular pathways are involved in the regulation of intestinal epithelial cell polarity. These include the Wnt, Notch, Hippo, transforming growth factor-β (TGF-β)/bone morphogenetic protein (BMP) and Hedgehog pathways, most of which were identified in lower organisms where they play important roles during embryogenesis. These pathways are also used in adult organisms to regulate multiple self-renewing organs. Understanding the interactions between these molecular mechanisms and intestinal barrier function will therefore provide important insight into the pathogenesis of intestinal-based immune-mediated diseases. PMID:24244877

  11. Nutritional Keys for Intestinal Barrier Modulation

    PubMed Central

    De Santis, Stefania; Cavalcanti, Elisabetta; Mastronardi, Mauro; Jirillo, Emilio; Chieppa, Marcello

    2015-01-01

    The intestinal tract represents the largest interface between the external environment and the human body. Nutrient uptake mostly happens in the intestinal tract, where the epithelial surface is constantly exposed to dietary antigens. Since inflammatory response toward these antigens may be deleterious for the host, a plethora of protective mechanisms take place to avoid or attenuate local damage. For instance, the intestinal barrier is able to elicit a dynamic response that either promotes or impairs luminal antigens adhesion and crossing. Regulation of intestinal barrier is crucial to control intestinal permeability whose increase is associated with chronic inflammatory conditions. The cross talk among bacteria, immune, and dietary factors is able to modulate the mucosal barrier function, as well as the intestinal permeability. Several nutritional products have recently been proposed as regulators of the epithelial barrier, even if their effects are in part contradictory. At the same time, the metabolic function of the microbiota generates new products with different effects based on the dietary content. Besides conventional treatments, novel therapies based on complementary nutrients are now growing. Fecal therapy has been recently used for the clinical treatment of refractory Clostridium difficile infection instead of the classical antibiotic therapy. In the present review, we will outline the epithelial response to nutritional components derived from dietary intake and microbial fermentation focusing on the consequent effects on the integrity of the epithelial barrier. PMID:26697008

  12. Intestinal inflammation and mucosal barrier function.

    PubMed

    Sánchez de Medina, Fermín; Romero-Calvo, Isabel; Mascaraque, Cristina; Martínez-Augustin, Olga

    2014-12-01

    Intestinal mucosal barrier function is the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules while preserving the ability to absorb nutrients. The central element is the epithelial layer, which physically separates the lumen and the internal milieu and is in charge of vectorial transport of ions, nutrients, and other substances. The secretion of mucus-forming mucins, sIgA, and antimicrobial peptides reinforces the mucosal barrier on the extraepithelial side, while a variety of immune cells contributes to mucosal defense in the inner side. Thus, the mucosal barrier is of physical, biochemical, and immune nature. In addition, the microbiota may be viewed as part of this system because of the mutual influence occurring between the host and the luminal microorganisms. Alteration of the mucosal barrier function with accompanying increased permeability and/or bacterial translocation has been linked with a variety of conditions, including inflammatory bowel disease. Genetic and environmental factors may converge to evoke a defective function of the barrier, which in turn may lead to overt inflammation of the intestine as a result of an exacerbated immune reaction toward the microbiota. According to this hypothesis, inflammatory bowel disease may be both precipitated and treated by either stimulation or downregulation of the different elements of the mucosal barrier, with the outcome depending on timing, the cell type affected, and other factors. In this review, we cover briefly the elements of the barrier and their involvement in functional defects and the resulting phenotype. PMID:25222662

  13. Probiotic bacteria and intestinal epithelial barrier function.

    PubMed

    Ohland, Christina L; Macnaughton, Wallace K

    2010-06-01

    The intestinal tract is a diverse microenvironment where more than 500 species of bacteria thrive. A single layer of epithelium is all that separates these commensal microorganisms and pathogens from the underlying immune cells, and thus epithelial barrier function is a key component in the arsenal of defense mechanisms required to prevent infection and inflammation. The epithelial barrier consists of a dense mucous layer containing secretory IgA and antimicrobial peptides as well as dynamic junctional complexes that regulate permeability between cells. Probiotics are live microorganisms that confer benefit to the host and that have been suggested to ameliorate or prevent diseases including antibiotic-associated diarrhea, irritable bowel syndrome, and inflammatory bowel disease. Probiotics likely function through enhancement of barrier function, immunomodulation, and competitive adherence to the mucus and epithelium. This review summarizes the evidence about effects of the many available probiotics with an emphasis on intestinal barrier function and the mechanisms affected by probiotics. PMID:20299599

  14. Intestinal barrier in inflammatory bowel disease

    PubMed Central

    Antoni, Lena; Nuding, Sabine; Wehkamp, Jan; Stange, Eduard F

    2014-01-01

    A complex mucosal barrier protects as the first line of defense the surface of the healthy intestinal tract from adhesion and invasion by luminal microorganisms. In this review, we provide an overview about the major components of this protective system as for example an intact epithelium, the synthesis of various antimicrobial peptides (AMPs) and the formation of the mucus layer. We highlight the crucial importance of their correct functioning for the maintenance of a proper intestinal function and the prevention of dysbiosis and disease. Barrier disturbances including a defective production of AMPs, alterations in thickness or composition of the intestinal mucus layer, alterations of pattern-recognition receptors, defects in the process of autophagy as well as unresolved endoplasmic reticulum stress result in an inadequate host protection and are thought to play a crucial role in the pathogenesis of the inflammatory bowel diseases Crohn’s disease and ulcerative colitis. PMID:24574793

  15. Mechanisms of Intestinal Barrier Dysfunction in Sepsis.

    PubMed

    Yoseph, Benyam P; Klingensmith, Nathan J; Liang, Zhe; Breed, Elise R; Burd, Eileen M; Mittal, Rohit; Dominguez, Jessica A; Petrie, Benjamin; Ford, Mandy L; Coopersmith, Craig M

    2016-07-01

    Intestinal barrier dysfunction is thought to contribute to the development of multiple organ dysfunction syndrome in sepsis. Although there are similarities in clinical course following sepsis, there are significant differences in the host response depending on the initiating organism and time course of the disease, and pathways of gut injury vary widely in different preclinical models of sepsis. The purpose of this study was to determine whether the timecourse and mechanisms of intestinal barrier dysfunction are similar in disparate mouse models of sepsis with similar mortalities. FVB/N mice were randomized to receive cecal ligation and puncture (CLP) or sham laparotomy, and permeability was measured to fluoresceinisothiocyanate conjugated-dextran (FD-4) six to 48 h later. Intestinal permeability was elevated following CLP at all timepoints measured, peaking at 6 to 12 h. Tight junction proteins claudin 1, 2, 3, 4, 5, 7, 8, 13, and 15, Junctional Adhesion Molecule-A (JAM-A), occludin, and ZO-1 were than assayed by Western blot, real-time polymerase chain reaction, and immunohistochemistry 12 h after CLP to determine potential mechanisms underlying increases in intestinal permeability. Claudin 2 and JAM-A were increased by sepsis, whereas claudin-5 and occludin were decreased by sepsis. All other tight junction proteins were unchanged. A further timecourse experiment demonstrated that alterations in claudin-2 and occludin were detectable as early as 1 h after the onset of sepsis. Similar experiments were then performed in a different group of mice subjected to Pseudomonas aeruginosa pneumonia. Mice with pneumonia had an increase in intestinal permeability similar in timecourse and magnitude to that seen in CLP. Similar changes in tight junction proteins were seen in both models of sepsis although mice subjected to pneumonia also had a marked decrease in ZO-1 not seen in CLP. These results indicate that two disparate, clinically relevant models of sepsis

  16. Role of microRNAs in Alcohol-Induced Multi-Organ Injury

    PubMed Central

    Natarajan, Sathish Kumar; Pachunka, Joseph M.; Mott, Justin L.

    2015-01-01

    Alcohol consumption and its abuse is a major health problem resulting in significant healthcare cost in the United States. Chronic alcoholism results in damage to most of the vital organs in the human body. Among the alcohol-induced injuries, alcoholic liver disease is one of the most prevalent in the United States. Remarkably, ethanol alters expression of a wide variety of microRNAs that can regulate alcohol-induced complications or dysfunctions. In this review, we will discuss the role of microRNAs in alcoholic pancreatitis, alcohol-induced liver damage, intestinal epithelial barrier dysfunction, and brain damage including altered hippocampus structure and function, and neuronal loss, alcoholic cardiomyopathy, and muscle damage. Further, we have reviewed the role of altered microRNAs in the circulation, teratogenic effects of alcohol, and during maternal or paternal alcohol consumption. PMID:26610589

  17. IBD Candidate Genes and Intestinal Barrier Regulation

    PubMed Central

    McCole, Declan F.

    2015-01-01

    Technological advances in the large scale analysis of human genetics have generated profound insights into possible genetic contributions to chronic diseases including the inflammatory bowel diseases (IBDs), Crohn’s disease and ulcerative colitis. To date, 163 distinct genetic risk loci have been associated with either Crohn’s disease or ulcerative colitis, with a substantial degree of genetic overlap between these 2 conditions. Although many risk variants show a reproducible correlation with disease, individual gene associations only affect a subset of patients, and the functional contribution(s) of these risk variants to the onset of IBD is largely undetermined. Although studies in twins have demonstrated that the development of IBD is not mediated solely by genetic risk, it is nevertheless important to elucidate the functional consequences of risk variants for gene function in relevant cell types known to regulate key physiological processes that are compromised in IBD. This article will discuss IBD candidate genes that are known to be, or are suspected of being, involved in regulating the intestinal epithelial barrier and several of the physiological processes presided over by this dynamic and versatile layer of cells. This will include assembly and regulation of tight junctions, cell adhesion and polarity, mucus and glycoprotein regulation, bacterial sensing, membrane transport, epithelial differentiation, and restitution. PMID:25215613

  18. Sodium butyrate protects the intestinal barrier function in peritonitic mice

    PubMed Central

    Han, Xiaofeng; Song, Huimin; Wang, Yunlei; Sheng, Yingmo; Chen, Jie

    2015-01-01

    Objective: Peritonitis is a commonly seen disease with high morbidity and mortality. It is prevalently considered that the impaired intestinal barrier during peritonitis is the access point of gut microbes into the blood system, and acts as the engine of the following systemic infection. In our previous study, we found that Sodium Butyrate (NaB) was protective on intestinal barrier function. In this study, we aim to evaluate the effects of NaB on overwhelming infection animal models of peritonitis. Methods: Mouse cecal ligation and puncture (CLP) model was used to study the effects of NaB on the intestinal barrier. Experimental animals were fed of NaB by gavage. Post-CLP mortality, gut permeability and intestinal histological alterations were studied. Results: Gastrointestinal NaB pharmacodynamics profiles after medication were studied. Measurements of NaB concentration in chyme showed significantly higher intestinal concentration of NaB in the NaB treated group than that of the control group. CLP-induced mortality was significantly decreased by oral NaB treatments. Gut permeability was largely increased after CLP, which was partially prevented by NaB feeding. Histological study showed that intestinal, especially ileal injury following peritonitis was substantially alleviated by NaB treatments. Moreover, tissue regeneration was also prompted by NaB. Conclusion: NaB has a potential protective effect on intestinal barrier function in peritonitis. PMID:26064302

  19. The Effect of Peritoneal Air Exposure on Intestinal Mucosal Barrier

    PubMed Central

    Bao, Jun; Tan, Shanjun; Yu, Wenkui; Lin, Zhiliang; Dong, Yi; Chen, Qiyi; Shi, Jialiang; Duan, Kaipeng; Bai, Xiaowu; Xu, Lin; Li, Jieshou

    2014-01-01

    Background. Damage of the intestinal mucosa barrier may result in intestinal bacterial and endotoxin translocation, leading to local and systemic inflammation. The present study was designed to investigate whether peritoneal air exposure induces damage of intestinal mucosal barrier. Methods. Sprague-Dawley rats (weighing 210 to 230 g) were randomized into five groups (6/group): a control group, a sham group, and three exposure groups with peritoneal air exposure for 1, 2, and 3 h, respectively. At 24 h after surgery, blood and terminal ileum were sampled. The serum D-lactate levels were determined using an ELISA kit. The intestinal permeability was determined by measuring the intestinal clearance of FITC-dextran (FD4). The histopathological changes in terminal ileum were also assessed. Results. Compared with the controls, peritoneal air exposure caused an increase in both serum D-lactate level and intestinal FD4 clearance, which were proportional to the length of peritoneal air exposure and correlated to Chiu's scores, indices for intestinal mucosal injury. Edema and inflammatory cells were also observed in mucosa and submucosa of ileum in three exposure groups. Conclusions. Peritoneal air exposure could induce damage to the intestinal mucosal barrier, which is proportional to the time length of peritoneal air exposure. PMID:25210511

  20. Regulation of the Intestinal Barrier Function by Host Defense Peptides

    PubMed Central

    Robinson, Kelsy; Deng, Zhuo; Hou, Yongqing; Zhang, Guolong

    2015-01-01

    Intestinal barrier function is achieved primarily through regulating the synthesis of mucins and tight junction (TJ) proteins, which are critical for maintaining optimal gut health and animal performance. An aberrant expression of TJ proteins results in increased paracellular permeability, leading to intestinal and systemic disorders. As an essential component of innate immunity, host defense peptides (HDPs) play a critical role in mucosal defense. Besides broad-spectrum antimicrobial activities, HDPs promotes inflammation resolution, endotoxin neutralization, wound healing, and the development of adaptive immune response. Accumulating evidence has also indicated an emerging role of HDPs in barrier function and intestinal homeostasis. HDP deficiency in the intestinal tract is associated with barrier dysfunction and dysbiosis. Several HDPs were recently shown to enhance mucosal barrier function by directly inducing the expression of multiple mucins and TJ proteins. Consistently, dietary supplementation of HDPs often leads to an improvement in intestinal morphology, production performance, and feed efficiency in livestock animals. This review summarizes current advances on the regulation of epithelial integrity and homeostasis by HDPs. Major signaling pathways mediating HDP-induced mucin and TJ protein synthesis are also discussed. As an alternative strategy to antibiotics, supplementation of exogenous HDPs or modulation of endogenous HDP synthesis may have potential to improve intestinal barrier function and animal health and productivity. PMID:26664984

  1. Claudins, dietary milk proteins, and intestinal barrier regulation.

    PubMed

    Kotler, Belinda M; Kerstetter, Jane E; Insogna, Karl L

    2013-01-01

    The family of claudin proteins plays an important role in regulating the intestinal barrier by modulating the permeability of tight junctions. The impact of dietary protein on claudin biology has not been studied extensively. Whey proteins have been reported to improve intestinal barrier function, but their mechanism of action is not clear. Recent studies, however, have demonstrated increased intestinal claudin expression in response to milk protein components. Reviewed here are new findings suggesting that whey-protein-derived transforming growth factor β transcriptionally upregulates claudin-4 expression via a Smad-4-dependent pathway. These and other data, including limited clinical studies, are summarized below and, in the aggregate, suggest a therapeutic role for whey protein in diseases of intestinal barrier dysfunction, perhaps, in part, by regulating claudin expression. PMID:23282252

  2. Chronic Kidney Disease Induced Intestinal Mucosal Barrier Damage Associated with Intestinal Oxidative Stress Injury

    PubMed Central

    Yu, Chao; Wang, Qiang; Zhou, Chunyu; Kang, Xin; Zhao, Shuang; Liu, Shuai; Fu, Huijun; Yu, Zhen; Peng, Ai

    2016-01-01

    Background. To investigate whether intestinal mucosal barrier was damaged or not in chronic kidney disease progression and the status of oxidative stress. Methods. Rats were randomized into two groups: a control group and a uremia group. The uremia rat model was induced by 5/6 kidney resection. In postoperative weeks (POW) 4, 6, 8, and 10, eight rats were randomly selected from each group to prepare samples for assessing systemic inflammation, intestinal mucosal barrier changes, and the status of intestinal oxidative stress. Results. The uremia group presented an increase trend over time in the serum tumor necrosis factor-alpha, interleukin-6 (IL-6) and IL-10, serum D-lactate and diamine oxidase, and intestinal permeability, and these biomarkers were significantly higher than those in control group in POW 8 and/or 10. Chiu's scores in uremia group were also increased over time, especially in POW 8 and 10. Furthermore, the intestinal malondialdehyde, superoxide dismutase, and glutathione peroxidase levels were significantly higher in uremia group when compared with those in control group in POW 8 and/or 10. Conclusions. The advanced chronic kidney disease could induce intestinal mucosal barrier damage and further lead to systemic inflammation. The underlying mechanism may be associated with the intestinal oxidative stress injury. PMID:27493661

  3. Alcohol and the Intestine

    PubMed Central

    Patel, Sheena; Behara, Rama; Swanson, Garth R.; Forsyth, Christopher B.; Voigt, Robin M.; Keshavarzian, Ali

    2015-01-01

    Alcohol abuse is a significant contributor to the global burden of disease and can lead to tissue damage and organ dysfunction in a subset of alcoholics. However, a subset of alcoholics without any of these predisposing factors can develop alcohol-mediated organ injury. The gastrointestinal tract (GI) could be an important source of inflammation in alcohol-mediated organ damage. The purpose of review was to evaluate mechanisms of alcohol-induced endotoxemia (including dysbiosis and gut leakiness), and highlight the predisposing factors for alcohol-induced dysbiosis and gut leakiness to endotoxins. Barriers, including immunologic, physical, and biochemical can regulate the passage of toxins into the portal and systemic circulation. In addition, a host of environmental interactions including those influenced by circadian rhythms can impact alcohol-induced organ pathology. There appears to be a role for therapeutic measures to mitigate alcohol-induced organ damage by normalizing intestinal dysbiosis and/or improving intestinal barrier integrity. Ultimately, the inflammatory process that drives progression into organ damage from alcohol appears to be multifactorial. Understanding the role of the intestine in the pathogenesis of alcoholic liver disease can pose further avenues for pathogenic and treatment approaches. PMID:26501334

  4. Heat stress: intestinal barrier and immune disruption in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Economic losses to the livestock industry due to heat stress (HS) are estimated to be greater than $2.0 billion annually. HS morbidity is linked to disruption of normal intestinal tract (IT) absorptive and barrier functions, is often manifested as decreased performance; however, extreme HS can have ...

  5. Functional changes of intestinal mucosal barrier in surgically critical patients

    PubMed Central

    Guo, Yuan-yuan; Liu, Mu-lin; He, Xian-di; Jiang, Cong-qiao; Liu, Rui-lin

    2010-01-01

    BACKGROUND: The gut is capable of inducing multiple organ dysfunction syndrome (MODS). In the diagnosis and treatment of critical ill patients, doctors should pay particular attention to the protection or recovery of intestinal barrier function. However, no reliable diagnostic criteria are available clinically. This study aimed to assess the changes of intestinal mucosal barrier function in surgically critical ill patients as well as their significance. METHODS: Thirty-eight surgically critical ill patients were enrolled as a study group (APACHE II>8 scores), and 15 non-critical ill patients without intestinal dysfunction were selected as a control group (APACHE II<6). General information, symptoms, physical signs, and APACHE II scores of the patients were recorded. The patients in the study group were subdivided into an intestinal dysfunction group (n=26) and a non-intestinal dysfunction group (n=12). Three ml venous blood was collected from the control group on admission and the same volume of plasma was collected from the study group both on admission and in the period of recovery. The plasma concentrations of endotoxin, diamine oxidase (DAO), D-lactate, and intestinal fatty-acid binding protein (iFABP) were detected respectively. The data collected were analyzed by the SPSS 17.0 software for Windows. RESULTS: The levels of variables were significantly higher in the study group than in the control group (P<0.01). They were higher in the intestinal dysfunction group than in the non-intestinal dysfunction group (DAO P<0.05, endotoxin, D-lactate, iFABP P<0.01). In the non-intestinal dysfunction group compared with the control group, the level of endotoxin was not significant (P>0.05), but the levels of DAO, D-lactate and iFABP were statistically significant (P<0.05). The levels of variables in acute stage were higher than those in recovery stage (P<0.01). The death group showed higher levels of variables than the survival group (endotoxin and D-lactate P<0.01, DAO

  6. Alcohol induced liver disease.

    PubMed Central

    Fleming, K A; McGee, J O

    1984-01-01

    Alcohol induces a variety of changes in the liver: fatty change, hepatitis, fibrosis, and cirrhosis. The histopathological appearances of these conditions are discussed, with special attention to differential diagnosis. Many forms of alcoholic liver disease are associated with Mallory body formation and fibrosis. Mallory bodies are formed, at least in part, from intermediate filaments. Associated changes in intermediate filament organisation in alcoholic liver disease also occur. Their significance in the pathogenesis of hepatocyte death may be related to abnormalities in messenger RNA function. The mechanisms underlying hepatic fibrogenesis are also discussed. Images PMID:6086722

  7. Epigenetic control of intestinal barrier function and inflammation in zebrafish

    PubMed Central

    Marjoram, Lindsay; Alvers, Ashley; Deerhake, M. Elizabeth; Bagwell, Jennifer; Mankiewicz, Jamie; Cocchiaro, Jordan L.; Beerman, Rebecca W.; Willer, Jason; Sumigray, Kaelyn D.; Katsanis, Nicholas; Rawls, John F.; Goll, Mary G.; Bagnat, Michel

    2015-01-01

    The intestinal epithelium forms a barrier protecting the organism from microbes and other proinflammatory stimuli. The integrity of this barrier and the proper response to infection requires precise regulation of powerful immune homing signals such as tumor necrosis factor (TNF). Dysregulation of TNF leads to inflammatory bowel diseases (IBD), but the mechanism controlling the expression of this potent cytokine and the events that trigger the onset of chronic inflammation are unknown. Here, we show that loss of function of the epigenetic regulator ubiquitin-like protein containing PHD and RING finger domains 1 (uhrf1) in zebrafish leads to a reduction in tnfa promoter methylation and the induction of tnfa expression in intestinal epithelial cells (IECs). The increase in IEC tnfa levels is microbe-dependent and results in IEC shedding and apoptosis, immune cell recruitment, and barrier dysfunction, consistent with chronic inflammation. Importantly, tnfa knockdown in uhrf1 mutants restores IEC morphology, reduces cell shedding, and improves barrier function. We propose that loss of epigenetic repression and TNF induction in the intestinal epithelium can lead to IBD onset. PMID:25730872

  8. Epigenetic control of intestinal barrier function and inflammation in zebrafish.

    PubMed

    Marjoram, Lindsay; Alvers, Ashley; Deerhake, M Elizabeth; Bagwell, Jennifer; Mankiewicz, Jamie; Cocchiaro, Jordan L; Beerman, Rebecca W; Willer, Jason; Sumigray, Kaelyn D; Katsanis, Nicholas; Tobin, David M; Rawls, John F; Goll, Mary G; Bagnat, Michel

    2015-03-01

    The intestinal epithelium forms a barrier protecting the organism from microbes and other proinflammatory stimuli. The integrity of this barrier and the proper response to infection requires precise regulation of powerful immune homing signals such as tumor necrosis factor (TNF). Dysregulation of TNF leads to inflammatory bowel diseases (IBD), but the mechanism controlling the expression of this potent cytokine and the events that trigger the onset of chronic inflammation are unknown. Here, we show that loss of function of the epigenetic regulator ubiquitin-like protein containing PHD and RING finger domains 1 (uhrf1) in zebrafish leads to a reduction in tnfa promoter methylation and the induction of tnfa expression in intestinal epithelial cells (IECs). The increase in IEC tnfa levels is microbe-dependent and results in IEC shedding and apoptosis, immune cell recruitment, and barrier dysfunction, consistent with chronic inflammation. Importantly, tnfa knockdown in uhrf1 mutants restores IEC morphology, reduces cell shedding, and improves barrier function. We propose that loss of epigenetic repression and TNF induction in the intestinal epithelium can lead to IBD onset. PMID:25730872

  9. Enteropathogenic E. coli: breaking the intestinal tight junction barrier

    PubMed Central

    Singh, Anand Prakash; Aijaz, Saima

    2016-01-01

    Enteropathogenic E. coli (EPEC) causes acute intestinal infections in infants in the developing world. Infection typically spreads through contaminated food and water and leads to severe, watery diarrhea. EPEC attaches to the intestinal epithelial cells and directly injects virulence factors which modulate multiple signaling pathways leading to host cell dysfunction. However, the molecular mechanisms that regulate the onset of diarrhea are poorly defined. A major target of EPEC is the host cell tight junction complex which acts as a barrier and regulates the passage of water and solutes through the paracellular space. In this review, we focus on the EPEC effectors that target the epithelial barrier, alter its functions and contribute to leakage through the tight junctions. PMID:27239268

  10. Vasoactive Intestinal Polypeptide Promotes Intestinal Barrier Homeostasis and Protection Against Colitis in Mice

    PubMed Central

    Wu, Xiujuan; Conlin, Victoria S.; Morampudi, Vijay; Ryz, Natasha R.; Nasser, Yasmin; Bhinder, Ganive; Bergstrom, Kirk S.; Yu, Hong B.; Waterhouse, Chris C. M.; Buchan, Allison M. J.; Popescu, Oana E.; Gibson, William T.; Waschek, James A.; Vallance, Bruce A.; Jacobson, Kevan

    2015-01-01

    Inflammatory bowel disease is a chronic gastrointestinal inflammatory disorder associated with changes in neuropeptide expression and function, including vasoactive intestinal peptide (VIP). VIP regulates intestinal vasomotor and secretomotor function and motility; however, VIP’s role in development and maintenance of colonic epithelial barrier homeostasis is unclear. Using VIP deficient (VIPKO) mice, we investigated VIP’s role in epithelial barrier homeostasis, and susceptibility to colitis. Colonic crypt morphology and epithelial barrier homeostasis were assessed in wildtype (WT) and VIPKO mice, at baseline. Colitic responses were evaluated following dinitrobenzene sulfonic acid (DNBS) or dextran-sodium sulfate (DSS) exposure. Mice were also treated with exogenous VIP. At baseline, VIPKO mice exhibited distorted colonic crypts, defects in epithelial cell proliferation and migration, increased apoptosis, and altered permeability. VIPKO mice also displayed reduced goblet cell numbers, and reduced expression of secreted goblet cell factors mucin 2 and trefoil factor 3. These changes were associated with reduced expression of caudal type homeobox 2 (Cdx2), a master regulator of intestinal function and homeostasis. DNBS and DSS-induced colitis were more severe in VIPKO than WT mice. VIP treatment rescued the phenotype, protecting VIPKO mice against DSS colitis, with results comparable to WT mice. In conclusion, VIP plays a crucial role in the development and maintenance of colonic epithelial barrier integrity under physiological conditions and promotes epithelial repair and homeostasis during colitis. PMID:25932952

  11. The intestinal epithelium as guardian of gut barrier integrity.

    PubMed

    Zhang, Kaiyi; Hornef, Mathias W; Dupont, Aline

    2015-11-01

    A single layer of epithelial cells separates the intestinal lumen from the underlying sterile tissue. It is exposed to a multitude of nutrients and a large number of commensal bacteria. Although the presence of commensal bacteria significantly contributes to nutrient digestion, vitamin synthesis and tissue maturation, their high number represents a permanent challenge to the integrity of the epithelial surface keeping the local immune system constantly on alert. In addition, the intestinal mucosa is challenged by a variety of enteropathogenic microorganisms. In both circumstances, the epithelium actively contributes to maintaining host-microbial homeostasis and antimicrobial host defence. It deploys a variety of mechanisms to restrict the presence of commensal bacteria to the intestinal lumen and to prevent translocation of commensal and pathogenic microorganisms to the underlying tissue. Enteropathogenic microorganisms in turn have learnt to evade the host's immune system and circumvent the antimicrobial host response. In the present article, we review recent advances that illustrate the intense and intimate host-microbial interaction at the epithelial level and improve our understanding of the mechanisms that maintain the integrity of the intestinal epithelial barrier. PMID:26294173

  12. Intestinal barrier function in neonatal foals: options for improvement.

    PubMed

    Vendrig, Johannes C; Fink-Gremmels, Johanna

    2012-07-01

    Gastrointestinal defence in the new-born is limited in comparison to adults, due to an immature epithelial barrier function and deficits in both innate and adaptive immune responses. Consequently, neonates (including foals) are at increased risk of disturbance to mucosal homeostasis during initial intestinal colonisation that may lead to excessive inflammation and bacterial translocation into the bloodstream, resulting in septicaemia. Bacterial recognition by Pattern Recognition Receptors (PRRs) and their downstream regulation of cytokine release have been shown to be pivotal for gastrointestinal mucosal homeostasis and the development of a functional intestinal barrier. Evidence suggests that selective PRR agonists limit the inflammatory responses and improve epithelial barrier function. Milk, and in particular colostrum, contain a broad array of oligosaccharides which seem to act as PRR agonists. This class of compounds forms a source for new dietary formulas that may orchestrate gut colonisation by the commensal flora in the early phase of life and so reduce the risks of inflammation and pathogen invasion. PMID:22377327

  13. The role of intestinal epithelial barrier function in the development of NEC

    PubMed Central

    Halpern, Melissa D; Denning, Patricia W

    2015-01-01

    The intestinal epithelial barrier plays an important role in maintaining host health. Breakdown of intestinal barrier function is known to play a role in many diseases such as infectious enteritis, idiopathic inflammatory bowel disease, and neonatal inflammatory bowel diseases. Recently, increasing research has demonstrated the importance of understanding how intestinal epithelial barrier function develops in the premature neonate in order to develop strategies to promote its maturation. Optimizing intestinal barrier function is thought to be key to preventing neonatal inflammatory bowel diseases such as necrotizing enterocolitis. In this review, we will first summarize the key components of the intestinal epithelial barrier, what is known about its development, and how this may explain NEC pathogenesis. Finally, we will review what therapeutic strategies may be used to promote optimal development of neonatal intestinal barrier function in order to reduce the incidence and severity of NEC. PMID:25927016

  14. Food Derived Bioactive Peptides and Intestinal Barrier Function

    PubMed Central

    Martínez-Augustin, Olga; Rivero-Gutiérrez, Belén; Mascaraque, Cristina; Sánchez de Medina, Fermín

    2014-01-01

    A wide range of food-derived bioactive peptides have been shown to exert health-promoting actions and are therefore considered functional foods or nutraceuticals. Some of these actions are related to the maintenance, reinforcement or repairment of the intestinal barrier function (IBF) whose role is to selectively allow the absorption of water, nutrients and ions while preventing the influx of microorganisms from the intestinal lumen. Alterations in the IBF have been related to many disorders, such as inflammatory bowel disease or metabolic syndrome. Components of IBF are the intestinal epithelium, the mucus layer, secretory immunoglobulin A and cells of the innate and adaptive immune systems. Here we review the effects of food derived bioactive peptides on these IBF components. In vitro and in vivo effects, both in healthy and disease states, have been reviewed. Although limited, the available information indicates a potential for food-derived peptides to modify IBF and to contribute to disease treatment, but further research is needed to better isolate responsible peptides, and to help define their mode of action. PMID:25501338

  15. Protective effect of bone marrow mesenchymal stem cells in intestinal barrier permeability after heterotopic intestinal transplantation

    PubMed Central

    Zhang, Wen; Shen, Zhong-Yang; Song, Hong-Li; Yang, Yang; Wu, Ben-Juan; Fu, Nan-Nan; Liu, Tao

    2014-01-01

    AIM: To explore the protective effect of bone marrow mesenchymal stem cells (BM MSCs) in the small intestinal mucosal barrier following heterotopic intestinal transplantation (HIT) in a rat model. METHODS: BM MSCs were isolated from male Lewis rats by density gradient centrifugation, cultured, and analyzed by flow cytometry. The HIT models were divided into a non-rejection group, saline-treated rejection group (via penile vein), and BM MSC–treated group (via penile vein). Intestinal mucosal barrier injury was estimated by diamine oxidase (DAO) and D-lactic acid (D-LA) expression levels. Tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), interleukin-10 (IL-10), and transforming growth factor-β (TGF-β) were detected by enzyme-linked immunosorbent assay. Ultrastructural change of tight junctions (TJs) was observed under transmission electron microscope. Expression levels of the TJ proteins occludin and zona occludens (ZO)-1, affected by the inflammatory factors, were measured using real-time polymerase chain reaction and Western blotting. RESULTS: The pathological score at each time point after surgery indicated significantly less serious injury in the BM MSCs-treated group than in the rejection group (P < 0.05). In the former, graft levels of DAO and D-LA were reduced, and TNF-α and INF-γ production was inhibited (at day 7: 10.6473 ± 0.0710 vs 17.2128 ± 0.4991, P < 0.05; 545.1506 ± 31.9416 vs 810.2637 ± 25.1175, P < 0.05). IL-10 and TGF-β production was increased greatly (at day 7: 125.7773 ± 4.7719 vs 80.3756 ± 2.5866, P < 0.05; 234.5273 ± 9.3980 vs 545.1506 ± 31.9416, P < 0.05). There was increased expression of occludin and ZO-1 protein (at day 7: 0.2674 ± 0.0128 vs 0.1352 ± 0.0142, P < 0.05; at day 5: 0.7189 ± 0.0289 vs 0.4556 ± 0.0242, P < 0.05) and mRNA (at day 7: 0.3860 ± 0.0254 vs 0.1673 ± 0.0369, P < 0.05; at day 5: 0.5727 ± 0.0419 vs 0.3598 ± 0.0242, P < 0.05). CONCLUSION: BM MSCs can improve intestinal barrier permeability

  16. Restoration of barrier function in injured intestinal mucosa.

    PubMed

    Blikslager, Anthony T; Moeser, Adam J; Gookin, Jody L; Jones, Samuel L; Odle, Jack

    2007-04-01

    Mucosal repair is a complex event that immediately follows acute injury induced by ischemia and noxious luminal contents such as bile. In the small intestine, villous contraction is the initial phase of repair and is initiated by myofibroblasts that reside immediately beneath the epithelial basement membrane. Subsequent events include crawling of healthy epithelium adjacent to the wound, referred to as restitution. This is a highly regulated event involving signaling via basement membrane integrins by molecules such as focal adhesion kinase and growth factors. Interestingly, however, ex vivo studies of mammalian small intestine have revealed the importance of closure of the interepithelial tight junctions and the paracellular space. The critical role of tight junction closure is underscored by the prominent contribution of the paracellular space to measures of barrier function such as transepithelial electrical resistance. Additional roles are played by subepithelial cell populations, including neutrophils, related to their role in innate immunity. The net result of reparative mechanisms is remarkably rapid closure of mucosal wounds in mammalian tissues to prevent the onset of sepsis. PMID:17429041

  17. Photobiomodulation on alcohol induced dysfunction

    NASA Astrophysics Data System (ADS)

    Yang, Zheng-Ping; Liu, Timon C.; Zhang, Yan; Wang, Yan-Fang

    2007-05-01

    Alcohol, which is ubiquitous today, is a major health concern. Its use was already relatively high among the youngest respondents, peaked among young adults, and declined in older age groups. Alcohol is causally related to more than 60 different medical conditions. Overall, 4% of the global burden of disease is attributable to alcohol, which accounts for about as much death and disability globally as tobacco and hypertension. Alcohol also promotes the generation of reactive oxygen species (ROS) and/or interferes with the body's normal defense mechanisms against these compounds through numerous processes, particularly in the liver. Photobiomodulation (PBM) is a cell-specific effect of low intensity monochromatic light or low intensity laser irradiation (LIL) on biological systems. The cellular effects of both alcohol and LIL are ligand-independent so that PBM might rehabilitate alcohol induced dysfunction. The PBM on alcohol induced human neutrophil dysfunction and rat chronic atrophic gastritis, the laser acupuncture on alcohol addiction, and intravascular PBM on alcoholic coma of patients and rats have been observed. The endonasal PBM (EPBM) mediated by Yangming channel, autonomic nervous systems and blood cells is suggested to treat alcohol induced dysfunction in terms of EPBM phenomena, the mechanism of alcohol induced dysfunction and our biological information model of PBM. In our opinion, the therapeutic effects of PBM might also be achieved on alcoholic myopathy.

  18. The role of immunomodulators on intestinal barrier homeostasis in experimental models.

    PubMed

    Andrade, Maria Emília Rabelo; Araújo, Raquel Silva; de Barros, Patrícia Aparecida Vieira; Soares, Anne Danieli Nascimento; Abrantes, Fernanda Alves; Generoso, Simone de Vasconcelos; Fernandes, Simone Odília Antunes; Cardoso, Valbert Nascimento

    2015-12-01

    The intestinal epithelium is composed of specialized epithelial cells that form a physical and biochemical barrier to commensal and pathogenic microorganisms. However, dysregulation of the epithelial barrier function can lead to increased intestinal permeability and bacterial translocation across the intestinal mucosa, which contributes to local and systemic immune activation. The increase in these parameters is associated with inflammatory bowel disease, physical exercise under heat stress, intestinal obstruction, ischemia, and mucositis, among other conditions. Lately, there has been growing interest in immunomodulatory nutrients and probiotics that can regulate host immune and inflammatory responses and possibly restore the intestinal barrier. Immunomodulators such as amino acids (glutamine, arginine, tryptophan, and citrulline), fatty acids (short-chain and omega-3 fatty acids and conjugated linoleic acids), and probiotics (Bifidobacterium, Saccharomyces, and Lactobacillus) have been reported in the literature. Here, we review the critical roles of immunomodulatory nutrients in supporting gut barrier integrity and function. PMID:25660317

  19. Regulation of intestinal epithelial cells transcriptome by enteric glial cells: impact on intestinal epithelial barrier functions

    PubMed Central

    2009-01-01

    Background Emerging evidences suggest that enteric glial cells (EGC), a major constituent of the enteric nervous system (ENS), are key regulators of intestinal epithelial barrier (IEB) functions. Indeed EGC inhibit intestinal epithelial cells (IEC) proliferation and increase IEB paracellular permeability. However, the role of EGC on other important barrier functions and the signalling pathways involved in their effects are currently unknown. To achieve this goal, we aimed at identifying the impact of EGC upon IEC transcriptome by performing microarray studies. Results EGC induced significant changes in gene expression profiling of proliferating IEC after 24 hours of co-culture. 116 genes were identified as differentially expressed (70 up-regulated and 46 down-regulated) in IEC cultured with EGC compared to IEC cultured alone. By performing functional analysis of the 116 identified genes using Ingenuity Pathway Analysis, we showed that EGC induced a significant regulation of genes favoring both cell-to-cell and cell-to-matrix adhesion as well as cell differentiation. Consistently, functional studies showed that EGC induced a significant increase in cell adhesion. EGC also regulated genes involved in cell motility towards an enhancement of cell motility. In addition, EGC profoundly modulated expression of genes involved in cell proliferation and cell survival, although no clear functional trend could be identified. Finally, important genes involved in lipid and protein metabolism of epithelial cells were shown to be differentially regulated by EGC. Conclusion This study reinforces the emerging concept that EGC have major protective effects upon the IEB. EGC have a profound impact upon IEC transcriptome and induce a shift in IEC phenotype towards increased cell adhesion and cell differentiation. This concept needs to be further validated under both physiological and pathophysiological conditions. PMID:19883504

  20. Lactobacillus rhamnosus GG supernatant promotes intestinal barrier function, balances Treg and TH17 cells and ameliorates hepatic injury in a mouse model of chronic-binge alcohol feeding.

    PubMed

    Chen, Rui-Cong; Xu, Lan-Man; Du, Shan-Jie; Huang, Si-Si; Wu, He; Dong, Jia-Jia; Huang, Jian-Rong; Wang, Xiao-Dong; Feng, Wen-Ke; Chen, Yong-Ping

    2016-01-22

    Impaired intestinal barrier function plays a critical role in alcohol-induced hepatic injury, and the subsequent excessive absorbed endotoxin and bacterial translocation activate the immune response that aggravates the liver injury. Lactobacillus rhamnosus GG supernatant (LGG-s) has been suggested to improve intestinal barrier function and alleviate the liver injury induced by chronic and binge alcohol consumption, but the underlying mechanisms are still not clear. In this study, chronic-binge alcohol fed model was used to determine the effects of LGG-s on the prevention of alcoholic liver disease in C57BL/6 mice and investigate underlying mechanisms. Mice were fed Lieber-DeCarli diet containing 5% alcohol for 10 days, and one dose of alcohol was gavaged on Day 11. In one group, LGG-s was supplemented along with alcohol. Control mice were fed isocaloric diet. Nine hours later the mice were sacrificed for analysis. Chronic-binge alcohol exposure induced an elevation in liver enzymes, steatosis and morphology changes, while LGG-s supplementation attenuated these changes. Treatment with LGG-s significantly improved intestinal barrier function reflected by increased mRNA expression of tight junction (TJ) proteins and villus-crypt histology in ileum, and decreased Escherichia coli (E. coli) protein level in liver. Importantly, flow cytometry analysis showed that alcohol reduced Treg cell population while increased TH17 cell population as well as IL-17 secretion, which was reversed by LGG-s administration. In conclusion, our findings indicate that LGG-s is effective in preventing chronic-binge alcohol exposure-induced liver injury and shed a light on the importance of the balance of Treg and TH17 cells in the role of LGG-s application. PMID:26617183

  1. Myosin Light Chain Kinase Mediates Intestinal Barrier Disruption following Burn Injury

    PubMed Central

    Chen, Chuanli; Wang, Pei; Su, Qin; Wang, Shiliang; Wang, Fengjun

    2012-01-01

    Background Severe burn injury results in the loss of intestinal barrier function, however, the underlying mechanism remains unclear. Myosin light chain (MLC) phosphorylation mediated by MLC kinase (MLCK) is critical to the pathophysiological regulation of intestinal barrier function. We hypothesized that the MLCK-dependent MLC phosphorylation mediates the regulation of intestinal barrier function following burn injury, and that MLCK inhibition attenuates the burn-induced intestinal barrier disfunction. Methodology/Principal Findings Male balb/c mice were assigned randomly to either sham burn (control) or 30% total body surface area (TBSA) full thickness burn without or with intraperitoneal injection of ML-9 (2 mg/kg), an MLCK inhibitor. In vivo intestinal permeability to fluorescein isothiocyanate (FITC)-dextran was measured. Intestinal mucosa injury was assessed histologically. Tight junction proteins ZO-1, occludin and claudin-1 was analyzed by immunofluorescent assay. Expression of MLCK and phosphorylated MLC in ileal mucosa was assessed by Western blot. Intestinal permeability was increased significantly after burn injury, which was accompanied by mucosa injury, tight junction protein alterations, and increase of both MLCK and MLC phosphorylation. Treatment with ML-9 attenuated the burn-caused increase of intestinal permeability, mucosa injury, tight junction protein alterations, and decreased MLC phosphorylation, but not MLCK expression. Conclusions/Significance The MLCK-dependent MLC phosphorylation mediates intestinal epithelial barrier dysfunction after severe burn injury. It is suggested that MLCK-dependent MLC phosphorylation may be a critical target for the therapeutic treatment of intestinal epithelial barrier disruption after severe burn injury. PMID:22529961

  2. Mechanism of acute pancreatitis complicated with injury of intestinal mucosa barrier*

    PubMed Central

    Zhang, Xi-ping; Zhang, Jie; Song, Qiao-ling; Chen, Han-qin

    2007-01-01

    Acute pancreatitis (AP) is a common acute abdomen in clinic with a rapid onset and dangerous pathogenetic condition. AP can cause an injury of intestinal mucosa barrier, leading to translocation of bacteria or endotoxin through multiple routes, bacterial translocation (BT), gutorigin endotoxaemia, and secondary infection of pancreatic tissue, and then cause systemic inflammatory response syndrome (SIRS) or multiple organ dysfunction syndrome (MODS), which are important factors influencing AP’s severity and mortality. Meanwhile, the injury of intestinal mucosa barrier plays a key role in AP’s process. Therefore, it is clinically important to study the relationship between the injury of intestinal mucosa barrier and AP. In addition, many factors such as microcirculation disturbance, ischemical reperfusion injury, excessive release of inflammatory mediators and apoptosis may also play important roles in the damage of intestinal mucosa barrier. In this review, we summarize studies on mechanisms of AP. PMID:18257123

  3. ClC-2 regulation of intestinal barrier function: Translation of basic science to therapeutic target.

    PubMed

    Jin, Younggeon; Blikslager, Anthony T

    2015-01-01

    The ClC-2 chloride channel is a member of the voltage-gated chloride channel family. ClC-2 is involved in various physiological processes, including fluid transport and secretion, regulation of cell volume and pH, maintaining the membrane potential of the cell, cell-to-cell communication, and tissue homeostasis. Recently, our laboratory has accumulated evidence indicating a critical role of ClC-2 in the regulation of intestinal barrier function by altering inter-epithelial tight junction composition. This review will detail the role of ClC-2 in intestinal barrier function during intestinal disorders, including experimental ischemia/reperfusion injury and dextran sodium sulfate (DSS)-induced inflammatory bowel disease. Details of pharmacological manipulation of ClC-2 via prostone agonists will also be provided in an effort to show the potential therapeutic relevance of ClC-2 regulation, particularly during intestinal barrier disruption. PMID:26716076

  4. Adenosine A2B receptor modulates intestinal barrier function under hypoxic and ischemia/reperfusion conditions

    PubMed Central

    Yang, Yang; Qiu, Yuan; Wang, Wensheng; Xiao, Weidong; Liang, Hongyin; Zhang, Chaojun; Yang, Hanwenbo; Teitelbaum, Daniel H; Sun, Li-Hua; Yang, Hua

    2014-01-01

    Background: Intestinal barrier function failure from ischemia/reperfusion (I/R) and acute hypoxia has been implicated as a critical determinant in the predisposition to intestinal inflammation and a number of inflammatory disorders. Here, we identified the role of Adenosine A2B receptor (A2BAR) in the regulation of intestinal barrier function under I/R and acute hypoxic conditions. Methods: C57BL/6J mice were used, and were randomized into three groups: Sham, I/R, IR+PSB1115 (a specific A2BAR antagonist) groups. After surgery, the small bowel was harvested for immunohistochemical staining, RNA and protein content, and intestinal permeability analyses. Using an epithelial cell culture model, we investigated the influence of hypoxia on the epithelial function, and the role of A2BAR in the expressions of tight junction and epithelial permeability. The expressions of Claudin-1, occludin and ZO-1 were detected by RT-PCR and Western-Blot. Epithelial barrier function was assessed with transepithelial resistance (TER). Results and conclusions: The A2BAR antagonist, PSB1115, significantly increased tight junction protein expression after intestinal I/R or acute hypoxia conditions. PSB1115 also attenuated the disrupted distribution of TJ proteins. Furthermore, inhibition of A2BAR attenuated the decrease in TER induced by I/R or acute hypoxic conditions, and maintained intestinal barrier function. Antagonism of A2BAR activity improves intestinal epithelial structure and barrier function in a mouse model of intestinal I/R and a cell model of acute hypoxia. These findings support a potentially destructive role for A2BAR under intestinal I/R and acute hypoxic conditions. PMID:24966910

  5. Effects of intraepithelial lymphocyte-derived cytokines on intestinal mucosal barrier function.

    PubMed

    Qiu, Yuan; Yang, Hua

    2013-10-01

    The mucosal surface of the gastrointestinal tract directly interacts with the mucosal lumen, which is continuously exposed to foreign antigens. Specialized intraepithelial lymphocytes (IELs), located between the basolateral surfaces of the epithelial cells, are important as the first line of defense against microbes as well as for their role in the maintenance of epithelial barrier homeostasis. Although IELs are mainly composed of T cells, they are phenotypically and functionally distinct from T cells in peripheral blood or the spleen. Not only are IELs stimulated by the antigens of the intestinal lumen but are they also stimulated by regulatory immune cells. The integrity of the intestinal mucosal barrier is closely tied to the IEL function. Cytokines produced by IELs modulate the cellular functions that trigger the downstream signaling pathways and mediate the barrier homeostasis. In this review, we will address the broad spectrum of cytokines that are derived from IELs and the functional regulation of these cytokines on the intestinal barrier. PMID:23692551

  6. Antimicrobial peptide Cathelicidin-BF prevents intestinal barrier dysfunction in a mouse model of endotoxemia.

    PubMed

    Song, Deguang; Zong, Xin; Zhang, Haiwen; Wang, Tenghao; Yi, Hongbo; Luan, Chao; Wang, Yizhen

    2015-03-01

    Intestinal barrier functions are altered during the development of sepsis. Cathelicidin antimicrobial peptides, such as LL-37 and mCRAMP, can protect animals against intestinal barrier dysfunction. Cathelicidin-BF (C-BF), a new cathelicidin peptide purified from the venom of the snake Bungarus fasciatus, has been shown to have both antimicrobial and anti-inflammatory properties. This study investigated whether C-BF pretreatment could protect the intestinal barrier against dysfunction in a mouse model of endotoxemia, induced by intraperitoneal injection of LPS (10mg/kg). Mice were treated with low or high dose C-BF before treatment with LPS, and samples were collected 5h after LPS treatment. C-BF reduced LPS induced intestinal histological damage and gut permeability to 4 KD Fluorescein-isothiocyanate-conjugated dextran. Pretreatment with C-BF prevented LPS induced intestinal tight junction disruption and epithelial cell apoptosis. Moreover, C-BF down regulated the expression and secretion of TNF-α, a process involving the NF-κB signaling pathway. C-BF also reduced LPS induced TNF-α expression through the NF-κB signaling pathway in mouse RAW 264.7 macrophages. These findings indicate that C-BF can prevent gut barrier dysfunction induced by LPS, suggesting that C-BF may be used to develop a prophylactic agent for intestinal injury in endotoxemia. PMID:25639228

  7. Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers.

    PubMed

    Shin, Hee Soon; Jung, Sun Young; Back, Su Yeon; Do, Jeong-Ryong; Shon, Dong-Hwa

    2015-01-01

    Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function. PMID:26550018

  8. Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers

    PubMed Central

    Shin, Hee Soon; Jung, Sun Young; Back, Su Yeon; Do, Jeong-Ryong; Shon, Dong-Hwa

    2015-01-01

    Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function. PMID:26550018

  9. The food contaminant deoxynivalenol, decreases intestinal barrier permeability and reduces claudin expression

    SciTech Connect

    Pinton, Philippe; Nougayrede, Jean-Philippe; Del Rio, Juan-Carlos; Moreno, Carolina; Marin, Daniela E.; Ferrier, Laurent; Bracarense, Ana-Paula; Kolf-Clauw, Martine; Oswald, Isabelle P.

    2009-05-15

    'The gastrointestinal tract represents the first barrier against food contaminants as well as the first target for these toxicants. Deoxynivalenol (DON) is a mycotoxin that commonly contaminates cereals and causes various toxicological effects. Through consumption of contaminated cereals and cereal products, human and pigs are exposed to this mycotoxin. Using in vitro, ex vivo and in vivo approaches, we investigated the effects of DON on the intestinal epithelium. We demonstrated that, in intestinal epithelial cell lines from porcine (IPEC-1) or human (Caco-2) origin, DON decreases trans-epithelial electrical resistance (TEER) and increases in a time and dose-dependent manner the paracellular permeability to 4 kDa dextran and to pathogenic Escherichia coli across intestinal cell monolayers. In pig explants treated with DON, we also observed an increased permeability of intestinal tissue. These alterations of barrier function were associated with a specific reduction in the expression of claudins, which was also seen in vivo in the jejunum of piglets exposed to DON-contaminated feed. In conclusion, DON alters claudin expression and decreases the barrier function of the intestinal epithelium. Considering that high levels of DON may be present in food or feed, consumption of DON-contaminated food/feed may induce intestinal damage and has consequences for human and animal health.

  10. Intestinal barrier: A gentlemen’s agreement between microbiota and immunity

    PubMed Central

    Caricilli, Andrea Moro; Castoldi, Angela; Câmara, Niels Olsen Saraiva

    2014-01-01

    Our body is colonized by more than a hundred trillion commensals, represented by viruses, bacteria and fungi. This complex interaction has shown that the microbiome system contributes to the host’s adaptation to its environment, providing genes and functionality that give flexibility of diet and modulate the immune system in order not to reject these symbionts. In the intestine, specifically, the microbiota helps developing organ structures, participates of the metabolism of nutrients and induces immunity. Certain components of the microbiota have been shown to trigger inflammatory responses, whereas others, anti-inflammatory responses. The diversity and the composition of the microbiota, thus, play a key role in the maintenance of intestinal homeostasis and explain partially the link between intestinal microbiota changes and gut-related disorders in humans. Tight junction proteins are key molecules for determination of the paracellular permeability. In the context of intestinal inflammatory diseases, the intestinal barrier is compromised, and decreased expression and differential distribution of tight junction proteins is observed. It is still unclear what is the nature of the luminal or mucosal factors that affect the tight junction proteins function, but the modulation of the immune cells found in the intestinal lamina propria is hypothesized as having a role in this modulation. In this review, we provide an overview of the current understanding of the interaction of the gut microbiota with the immune system in the development and maintenance of the intestinal barrier. PMID:24891972

  11. Death following traumatic brain injury in Drosophila is associated with intestinal barrier dysfunction

    PubMed Central

    Katzenberger, Rebeccah J; Chtarbanova, Stanislava; Rimkus, Stacey A; Fischer, Julie A; Kaur, Gulpreet; Seppala, Jocelyn M; Swanson, Laura C; Zajac, Jocelyn E; Ganetzky, Barry; Wassarman, David A

    2015-01-01

    Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Unfavorable TBI outcomes result from primary mechanical injuries to the brain and ensuing secondary non-mechanical injuries that are not limited to the brain. Our genome-wide association study of Drosophila melanogaster revealed that the probability of death following TBI is associated with single nucleotide polymorphisms in genes involved in tissue barrier function and glucose homeostasis. We found that TBI causes intestinal and blood–brain barrier dysfunction and that intestinal barrier dysfunction is highly correlated with the probability of death. Furthermore, we found that ingestion of glucose after a primary injury increases the probability of death through a secondary injury mechanism that exacerbates intestinal barrier dysfunction. Our results indicate that natural variation in the probability of death following TBI is due in part to genetic differences that affect intestinal barrier dysfunction. DOI: http://dx.doi.org/10.7554/eLife.04790.001 PMID:25742603

  12. Effects of acute intra-abdominal hypertension on multiple intestinal barrier functions in rats

    PubMed Central

    Leng, Yuxin; Yi, Min; Fan, Jie; Bai, Yu; Ge, Qinggang; Yao, Gaiqi

    2016-01-01

    Intra-abdominal hypertension (IAH) is a common and serious complication in critically ill patients for which there is no well-defined treatment strategy. Here, we explored the effect of IAH on multiple intestinal barriers and discussed whether the alteration in microflora provides clues to guide the rational therapeutic treatment of intestinal barriers during IAH. Using a rat model, we analysed the expression of tight junction proteins (TJs), mucins, chemotactic factors, and Toll-like receptor 4 (TLR4) by immunohistochemistry. We also analysed the microflora populations using 16S rRNA sequencing. We found that, in addition to enhanced permeability, acute IAH (20 mmHg for 90 min) resulted in significant disturbances to mucosal barriers. Dysbiosis of the intestinal microbiota was also induced, as represented by decreased Firmicutes (relative abundance), increased Proteobacteria and migration of Bacteroidetes from the colon to the jejunum. At the genus level, Lactobacillus species and Peptostreptococcaceae incertae sedis were decreased, whereas levels of lactococci remained unchanged. Our findings outline the characteristics of IAH-induced barrier changes, indicating that intestinal barriers might be treated to alleviate IAH, and the microflora may be an especially relevant target. PMID:26980423

  13. LIGHT signals directly to intestinal epithelia to cause barrier dysfunction via cytoskeletal and endocytic mechanisms

    PubMed Central

    Schwarz, Brad T.; Wang, Fengjun; Shen, Le; Clayburgh, Daniel R.; Su, Liping; Wang, Yingmin; Fu, Yang-Xin; Turner, Jerrold R.

    2009-01-01

    BACKGROUND & AIMS LIGHT (lymphotoxin-like inducible protein that competes with glycoprotein D for herpes virus entry on T cells) is a TNF core family member that regulates T cell activation and causes experimental inflammatory bowel disease. Additional data suggest that LIGHT may be involved in the pathogenesis of human inflammatory bowel disease. The aim of this study was to determine if LIGHT was capable of signaling directly to intestinal epithelia and to define the mechanisms and consequences of such signaling. METHODS The effects of LIGHT and interferon-γ (IFN-γ) on barrier function, cytoskeletal regulation, and tight junction structure were assessed in mice and intestinal epithelial monolayers. RESULTS LIGHT induced barrier loss in cultured epithelia via myosin II regulatory light chain (MLC) phosphorylation; both barrier loss and MLC phosphorylation were reversed by MLC kinase (MLCK) inhibition. IFN-γ pretreatment, which induced lymphotoxin β receptor (LTβR) expression, was required for these effects and neither barrier dysfunction nor intestinal epithelial MLC phosphorylation occurred in LTβR-knockout mice. In cultured monolayers, endocytosis of the tight junction protein occludin correlated with barrier loss. Internalized occludin co-localized with caveolin-1. LIGHT-induced occludin endocytosis and barrier loss were both prevented by inhibition of caveolar endocytosis. CONCLUSIONS T cell-derived LIGHT activates intestinal epithelial LTβR to disrupt barrier function. This requires MLCK activation and caveolar endocytosis. These data suggest a novel role for LIGHT in disease pathogenesis and suggest that inhibition of MLCK-dependent caveolar endocytosis may represent an approach to restoring barrier function in inflammatory bowel disease. PMID:17570213

  14. Electroacupuncture at Bilateral Zusanli Points (ST36) Protects Intestinal Mucosal Immune Barrier in Sepsis.

    PubMed

    Zhu, Mei-Fei; Xing, Xi; Lei, Shu; Wu, Jian-Nong; Wang, Ling-Cong; Huang, Li-Quan; Jiang, Rong-Lin

    2015-01-01

    Sepsis results in high morbidity and mortality. Immunomodulation strategies could be an adjunctive therapy to treat sepsis. Acupuncture has also been used widely for many years in China to treat sepsis. However, the underlying mechanisms are not well-defined. We demonstrated here that EA preconditioning at ST36 obviously ameliorated CLP-induced intestinal injury and high permeability and reduced the mortality of CLP-induced sepsis rats. Moreover, electroacupuncture (EA) pretreatment exerted protective effects on intestinal mucosal immune barrier by increasing the concentration of sIgA and the percentage of CD3+, γ/δ, and CD4+ T cells and the ratio of CD4+/CD8+ T cells. Although EA at ST36 treatments immediately after closing the abdomen in the CLP procedure with low-frequency or high-frequency could not reduce the mortality of CLP-induced sepsis in rats, these EA treatments could also significantly improve intestinal injury index in rats with sepsis and obviously protected intestinal mucosal immune barrier. In conclusion, our findings demonstrated that EA at ST36 could improve intestinal mucosal immune barrier in sepsis induced by CLP, while the precise mechanism underlying the effects needs to be further elucidated. PMID:26346309

  15. Anthrax lethal toxin disrupts intestinal barrier function and causes systemic infections with enteric bacteria.

    PubMed

    Sun, Chen; Fang, Hui; Xie, Tao; Auth, Roger D; Patel, Nayana; Murray, Patrick R; Snoy, Philip J; Frucht, David M

    2012-01-01

    A variety of intestinal pathogens have virulence factors that target mitogen activated protein kinase (MAPK) signaling pathways, including Bacillus anthracis. Anthrax lethal toxin (LT) has specific proteolytic activity against the upstream regulators of MAPKs, the MAPK kinases (MKKs). Using a murine model of intoxication, we show that LT causes the dose-dependent disruption of intestinal epithelial integrity, characterized by mucosal erosion, ulceration, and bleeding. This pathology correlates with an LT-dependent blockade of intestinal crypt cell proliferation, accompanied by marked apoptosis in the villus tips. C57BL/6J mice treated with intravenous LT nearly uniformly develop systemic infections with commensal enteric organisms within 72 hours of administration. LT-dependent intestinal pathology depends upon its proteolytic activity and is partially attenuated by co-administration of broad spectrum antibiotics, indicating that it is both a cause and an effect of infection. These findings indicate that targeting of MAPK signaling pathways by anthrax LT compromises the structural integrity of the mucosal layer, serving to undermine the effectiveness of the intestinal barrier. Combined with the well-described immunosuppressive effects of LT, this disruption of the intestinal barrier provides a potential mechanism for host invasion via the enteric route, a common portal of entry during the natural infection cycle of Bacillus anthracis. PMID:22438953

  16. Zinc’s impact on intestinal barrier function and zinc trafficking during coccidial caccine challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to evaluate the effects of Zn supplementation on intestinal barrier function and Zn trafficking, three dietary regimens were formulated: a basal corn/SBM diet formulated with a Zn-free vitamin/mineral premix (Basal), and two Zn regimens formulated to provide 90 mg/kg total dietary Zn from ...

  17. Claudin-2 as a mediator of leaky gut barrier during intestinal inflammation.

    PubMed

    Luettig, J; Rosenthal, R; Barmeyer, C; Schulzke, J D

    2015-01-01

    The epithelial tight junction determines the paracellular water and ion movement in the intestine and also prevents uptake of larger molecules, including antigens, in an uncontrolled manner. Claudin-2, one of the 27 mammalian claudins regulating that barrier function, forms a paracellular channel for small cations and water. It is typically expressed in leaky epithelia like proximal nephron and small intestine and provides a major pathway for the paracellular transport of sodium, potassium, and fluid. In intestinal inflammation (Crohn's disease, ulcerative colitis), immune-mediated diseases (celiac disease), and infections (HIV enteropathy), claudin-2 is upregulated in small and large intestine and contributes to diarrhea via a leak flux mechanism. In parallel to that upregulation, other epithelial and tight junctional features are altered and the luminal uptake of antigenic macromolecules is enhanced, for which claudin-2 may be partially responsible through induction of tight junction strand discontinuities. PMID:25838982

  18. Effect of Polysaccharides from Acanthopanax senticosus on Intestinal Mucosal Barrier of Escherichia coli Lipopolysaccharide Challenged Mice.

    PubMed

    Han, Jie; Xu, Yunhe; Yang, Di; Yu, Ning; Bai, Zishan; Bian, Lianquan

    2016-01-01

    To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) in preventing lipopolysaccharide (LPS)-induced intestinal injury, 18 mice (at 5 wk of age) were assigned to three groups with 6 replicates of one mouse each. Mice were administrated by oral gavage with or without ASPS (300 mg/kg body weight) for 14 days and were injected with saline or LPS at 15 days. Intestinal samples were collected at 4 h post-challenge. The results showed that ASPS ameliorated LPS-induced deterioration of digestive ability of LPS-challenged mice, indicated by an increase in intestinal lactase activity (45%, p<0.05), and the intestinal morphology, as proved by improved villus height (20.84%, p<0.05) and villus height:crypt depth ratio (42%, p<0.05), and lower crypt depth in jejunum (15.55%, p<0.05), as well as enhanced intestinal tight junction proteins expression involving occludin-1 (71.43%, p<0.05). ASPS also prevented intestinal inflammation response, supported by decrease in intestinal inflammatory mediators including tumor necrosis factor α (22.28%, p<0.05) and heat shock protein (HSP70) (77.42%, p<0.05). In addition, intestinal mucus layers were also improved by ASPS, as indicated by the increase in number of goblet cells (24.89%, p<0.05) and intestinal trefoil peptide (17.75%, p<0.05). Finally, ASPS facilitated mRNA expression of epidermal growth factor (100%, p<0.05) and its receptor (200%, p<0.05) gene. These results indicate that ASPS can prevent intestinal mucosal barrier injury under inflammatory conditions, which may be associated with up-regulating gene mRNA expression of epidermal growth factor and its receptor. PMID:26732337

  19. Effect of Polysaccharides from Acanthopanax senticosus on Intestinal Mucosal Barrier of Escherichia coli Lipopolysaccharide Challenged Mice

    PubMed Central

    Han, Jie; Xu, Yunhe; Yang, Di; Yu, Ning; Bai, Zishan; Bian, Lianquan

    2016-01-01

    To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) in preventing lipopolysaccharide (LPS)-induced intestinal injury, 18 mice (at 5 wk of age) were assigned to three groups with 6 replicates of one mouse each. Mice were administrated by oral gavage with or without ASPS (300 mg/kg body weight) for 14 days and were injected with saline or LPS at 15 days. Intestinal samples were collected at 4 h post-challenge. The results showed that ASPS ameliorated LPS-induced deterioration of digestive ability of LPS-challenged mice, indicated by an increase in intestinal lactase activity (45%, p<0.05), and the intestinal morphology, as proved by improved villus height (20.84%, p<0.05) and villus height:crypt depth ratio (42%, p<0.05), and lower crypt depth in jejunum (15.55%, p<0.05), as well as enhanced intestinal tight junction proteins expression involving occludin-1 (71.43%, p<0.05). ASPS also prevented intestinal inflammation response, supported by decrease in intestinal inflammatory mediators including tumor necrosis factor α (22.28%, p<0.05) and heat shock protein (HSP70) (77.42%, p<0.05). In addition, intestinal mucus layers were also improved by ASPS, as indicated by the increase in number of goblet cells (24.89%, p<0.05) and intestinal trefoil peptide (17.75%, p<0.05). Finally, ASPS facilitated mRNA expression of epidermal growth factor (100%, p<0.05) and its receptor (200%, p<0.05) gene. These results indicate that ASPS can prevent intestinal mucosal barrier injury under inflammatory conditions, which may be associated with up-regulating gene mRNA expression of epidermal growth factor and its receptor. PMID:26732337

  20. Hydroxyethyl Starch (HES 130/0.4) Impairs Intestinal Barrier Integrity and Metabolic Function: Findings from a Mouse Model of the Isolated Perfused Small Intestine

    PubMed Central

    Dombrowsky, Heike; Zitta, Karina; Bein, Berthold; Krause, Thorsten; Goldmann, Torsten; Frerichs, Inez; Steinfath, Markus; Weiler, Norbert; Albrecht, Martin

    2015-01-01

    Background The application of hydroxyethyl starch (HES) for volume resuscitation is controversially discussed and clinical studies have suggested adverse effects of HES substitution, leading to increased patient mortality. Although, the intestine is of high clinical relevance and plays a crucial role in sepsis and inflammation, information about the effects of HES on intestinal function and barrier integrity is very scarce. We therefore evaluated the effects of clinically relevant concentrations of HES on intestinal function and barrier integrity employing an isolated perfused model of the mouse small intestine. Methods An isolated perfused model of the mouse small intestine was established and intestines were vascularly perfused with a modified Krebs-Henseleit buffer containing 3% Albumin (N=7) or 3% HES (130/0.4; N=7). Intestinal metabolic function (galactose uptake, lactate-to-pyruvate ratio), edema formation (wet-to-dry weight ratio), morphology (histological and electron microscopical analysis), fluid shifts within the vascular, lymphatic and luminal compartments, as well as endothelial and epithelial barrier permeability (FITC-dextran translocation) were evaluated in both groups. Results Compared to the Albumin group, HES perfusion did not significantly change the wet-to-dry weight ratio and lactate-to-pyruvate ratio. However, perfusing the small intestine with 3% HES resulted in a significant loss of vascular fluid (p<0.01), an increased fluid accumulation in the intestinal lumen (p<0.001), an enhanced translocation of FITC-dextran from the vascular to the luminal compartment (p<0.001) and a significantly impaired intestinal galactose uptake (p<0.001). Morphologically, these findings were associated with an aggregation of intracellular vacuoles within the intestinal epithelial cells and enlarged intercellular spaces. Conclusion A vascular perfusion with 3% HES impairs the endothelial and epithelial barrier integrity as well as metabolic function of the small

  1. TLR2 mediates gap junctional intercellular communication through connexin-43 in intestinal epithelial barrier injury.

    PubMed

    Ey, Birgit; Eyking, Annette; Gerken, Guido; Podolsky, Daniel K; Cario, Elke

    2009-08-14

    Gap junctional intercellular communication (GJIC) coordinates cellular functions essential for sustaining tissue homeostasis; yet its regulation in the intestine is not well understood. Here, we identify a novel physiological link between Toll-like receptor (TLR) 2 and GJIC through modulation of Connexin-43 (Cx43) during acute and chronic inflammatory injury of the intestinal epithelial cell (IEC) barrier. Data from in vitro studies reveal that TLR2 activation modulates Cx43 synthesis and increases GJIC via Cx43 during IEC injury. The ulcerative colitis-associated TLR2-R753Q mutant targets Cx43 for increased proteasomal degradation, impairing TLR2-mediated GJIC during intestinal epithelial wounding. In vivo studies using mucosal RNA interference show that TLR2-mediated mucosal healing depends functionally on intestinal epithelial Cx43 during acute inflammatory stress-induced damage. Mice deficient in TLR2 exhibit IEC-specific alterations in Cx43, whereas administration of a TLR2 agonist protects GJIC by blocking accumulation of Cx43 and its hyperphosphorylation at Ser368 to prevent spontaneous chronic colitis in MDR1alpha-deficient mice. Finally, adding the TLR2 agonist to three-dimensional intestinal mucosa-like cultures of human biopsies preserves intestinal epithelial Cx43 integrity and polarization ex vivo. In conclusion, Cx43 plays an important role in innate immune control of commensal-mediated intestinal epithelial wound repair. PMID:19528242

  2. Cinnamon extract protects against acute alcohol-induced liver steatosis in mice.

    PubMed

    Kanuri, Giridhar; Weber, Synia; Volynets, Valentina; Spruss, Astrid; Bischoff, Stephan C; Bergheim, Ina

    2009-03-01

    Acute and chronic consumption of alcohol can cause increased intestinal permeability and bacterial overgrowth, thereby increasing portal endotoxin levels. This barrier impairment subsequently leads to an activation of hepatic Kupffer cells and increased release of reactive oxygen species as well as of tumor necrosis factor-alpha (TNFalpha). Recent studies have suggested that cinnamon extract may have antiinflammatory effects. In the present study, the protective effects of an alcoholic extract of cinnamon bark was assessed in a mouse model of acute alcohol-induced steatosis and in RAW 264.7 macrophages, used here as a model of Kupffer cells. Acute alcohol ingestion caused a >20-fold increase in hepatic lipid accumulation. Pretreatment with cinnamon extract significantly reduced the hepatic lipid accumulation. This protective effect of cinnamon extract was associated with an inhibition of the induction of the myeloid differentiation primary response gene (MyD) 88, inducible nitric oxide (NO) synthase (iNOS), and plasminogen activator inhibitor 1 mRNA expression found in livers of alcohol-treated animals. In vitro prechallenge with cinnamon extract suppressed lipopolysaccharide (LPS)-induced MyD88, iNOS, and TNFalpha expression as well as NO formation almost completely. Furthermore, LPS treatment of RAW 264.7 macrophages further resulted in degradation of inhibitor kappaB; this effect was almost completely blocked by cinnamon extract. Taken together, our data show that an alcohol extract of cinnamon bark may protect the liver from acute alcohol-induced steatosis through mechanisms involving the inhibition of MyD88 expression. PMID:19126670

  3. GUCY2C opposes systemic genotoxic tumorigenesis by regulating AKT-dependent intestinal barrier integrity.

    PubMed

    Lin, Jieru Egeria; Snook, Adam Eugene; Li, Peng; Stoecker, Brian Arthur; Kim, Gilbert Won; Magee, Michael Sullivan; Garcia, Alex Vladimir Mejia; Valentino, Michael Anthony; Hyslop, Terry; Schulz, Stephanie; Waldman, Scott Arthur

    2012-01-01

    The barrier separating mucosal and systemic compartments comprises epithelial cells, annealed by tight junctions, limiting permeability. GUCY2C recently emerged as an intestinal tumor suppressor coordinating AKT1-dependent crypt-villus homeostasis. Here, the contribution of GUCY2C to barrier integrity opposing colitis and systemic tumorigenesis is defined. Mice deficient in GUCY2C (Gucy2c(-/-)) exhibited barrier hyperpermeability associated with reduced junctional proteins. Conversely, activation of GUCY2C in mice reduced barrier permeability associated with increased junctional proteins. Further, silencing GUCY2C exacerbated, while activation reduced, chemical barrier disruption and colitis. Moreover, eliminating GUCY2C amplified, while activation reduced, systemic oxidative DNA damage. This genotoxicity was associated with increased spontaneous and carcinogen-induced systemic tumorigenesis in Gucy2c(-/-) mice. GUCY2C regulated barrier integrity by repressing AKT1, associated with increased junction proteins occludin and claudin 4 in mice and Caco2 cells in vitro. Thus, GUCY2C defends the intestinal barrier, opposing colitis and systemic genotoxicity and tumorigenesis. The therapeutic potential of this observation is underscored by the emerging clinical development of oral GUCY2C ligands, which can be used for chemoprophylaxis in inflammatory bowel disease and cancer. PMID:22384056

  4. Effects of Probiotics on Intestinal Mucosa Barrier in Patients With Colorectal Cancer after Operation

    PubMed Central

    Liu, Dun; Jiang, Xiao-Ying; Zhou, Lan-Shu; Song, Ji-Hong; Zhang, Xuan

    2016-01-01

    Abstract Many studies have found that probiotics or synbiotics can be used in patients with diarrhea or inflammatory bowel disease for the prevention and treatment of some pathologies by improving gastrointestinal barrier function. However, there are few studies availing the use of probiotics in patients with colorectal cancer. To lay the foundation for the study of nutritional support in colorectal cancer patients, a meta-analysis has been carried out to assess the efficacy of probiotics on the intestinal mucosa barrier in patients with colorectal cancer after operation. To estimate the efficacy of probiotics on the intestinal mucosa barrier in patients with colorectal cancer after operation, a meta-analysis of randomized controlled trials has been conducted. Databases including PubMed, Ovid, Embase, the Cochrane Central Register of Controlled Trials, and the China National Knowledge Infrastructure have been searched to identify suitable studies. Stata 12.0 was used for statistical analysis, and sensitivity analysis was also conducted. Six indicators were chosen to evaluate probiotics in protecting the intestinal mucosa barrier in patients with colorectal cancer. Ratios of lactulose to mannitol (L/M) and Bifidobacterium to Escherichia (B/E), occludin, bacterial translocation, and levels of secretory immunoglobulin A (SIgA), interleukin-6 (IL-6), and C-reactive protein (CRP) were chosen to evaluate probiotics in protecting the intestinal mucosa barrier in patients with colorectal cancer. Seventeen studies including 1242 patients were selected for meta-analysis, including 5 English studies and 12 Chinese studies. Significant effects were found in ratios of L/M (standardized mean difference = 3.83, P = 0.001) and B/E (standardized mean difference = 3.91, P = 0.000), occludin (standardized mean difference = 4.74, P = 0.000), bacterial translocation (standardized mean difference = 3.12, P = 0.002), and levels of SIgA (standardized mean

  5. High therapeutic efficacy of Cathelicidin-WA against postweaning diarrhea via inhibiting inflammation and enhancing epithelial barrier in the intestine

    PubMed Central

    Yi, Hongbo; Zhang, Lin; Gan, Zhenshun; Xiong, Haitao; Yu, Caihua; Du, Huahua; Wang, Yizhen

    2016-01-01

    Diarrhea is a leading cause of death among young mammals, especially during weaning. Here, we investigated the effects of Cathelicidin-WA (CWA) on diarrhea, intestinal morphology, inflammatory responses, epithelial barrier and microbiota in the intestine of young mammals during weaning. Piglets with clinical diarrhea were selected and treated with saline (control), CWA or enrofloxacin (Enro) for 4 days. Both CWA and Enro effectively attenuated diarrhea. Compared with the control, CWA decreased IL-6, IL-8 and IL-22 levels and reduced neutrophil infiltration into the jejunum. CWA inhibited inflammation by down-regulating the TLR4-, MyD88- and NF-κB-dependent pathways. Additionally, CWA improved intestinal morphology by increasing villus and microvillus heights and enhancing intestinal barrier function by increasing tight junction (TJ) protein expression and augmenting wound-healing ability in intestinal epithelial cells. CWA also improved microbiota composition and increased short-chain fatty acid (SCFA) levels in feces. By contrast, Enro not only disrupted the intestinal barrier but also negatively affected microbiota composition and SCFA levels in the intestine. In conclusion, CWA effectively attenuated inflammation, enhanced intestinal barrier function, and improved microbiota composition in the intestines of weaned piglets. These results suggest that CWA could be an effective and safe therapy for diarrhea or other intestinal diseases in young mammals. PMID:27181680

  6. High therapeutic efficacy of Cathelicidin-WA against postweaning diarrhea via inhibiting inflammation and enhancing epithelial barrier in the intestine.

    PubMed

    Yi, Hongbo; Zhang, Lin; Gan, Zhenshun; Xiong, Haitao; Yu, Caihua; Du, Huahua; Wang, Yizhen

    2016-01-01

    Diarrhea is a leading cause of death among young mammals, especially during weaning. Here, we investigated the effects of Cathelicidin-WA (CWA) on diarrhea, intestinal morphology, inflammatory responses, epithelial barrier and microbiota in the intestine of young mammals during weaning. Piglets with clinical diarrhea were selected and treated with saline (control), CWA or enrofloxacin (Enro) for 4 days. Both CWA and Enro effectively attenuated diarrhea. Compared with the control, CWA decreased IL-6, IL-8 and IL-22 levels and reduced neutrophil infiltration into the jejunum. CWA inhibited inflammation by down-regulating the TLR4-, MyD88- and NF-κB-dependent pathways. Additionally, CWA improved intestinal morphology by increasing villus and microvillus heights and enhancing intestinal barrier function by increasing tight junction (TJ) protein expression and augmenting wound-healing ability in intestinal epithelial cells. CWA also improved microbiota composition and increased short-chain fatty acid (SCFA) levels in feces. By contrast, Enro not only disrupted the intestinal barrier but also negatively affected microbiota composition and SCFA levels in the intestine. In conclusion, CWA effectively attenuated inflammation, enhanced intestinal barrier function, and improved microbiota composition in the intestines of weaned piglets. These results suggest that CWA could be an effective and safe therapy for diarrhea or other intestinal diseases in young mammals. PMID:27181680

  7. Deoxynivalenol affects in vitro intestinal epithelial cell barrier integrity through inhibition of protein synthesis

    SciTech Connect

    Van De Walle, Jacqueline; Sergent, Therese; Piront, Neil; Toussaint, Olivier; Schneider, Yves-Jacques; Larondelle, Yvan

    2010-06-15

    Deoxynivalenol (DON), one of the most common mycotoxin contaminants of raw and processed cereal food, adversely affects the gastrointestinal tract. Since DON acts as a protein synthesis inhibitor, the constantly renewing intestinal epithelium could be particularly sensitive to DON. We analyzed the toxicological effects of DON on intestinal epithelial protein synthesis and barrier integrity. Differentiated Caco-2 cells, as a widely used model of the human intestinal barrier, were exposed to realistic intestinal concentrations of DON (50, 500 and 5000 ng/ml) during 24 h. DON caused a concentration-dependent decrease in total protein content associated with a reduction in the incorporation of [{sup 3}H]-leucine, demonstrating its inhibitory effect on protein synthesis. DON simultaneously increased the paracellular permeability of the monolayer as reflected through a decreased transepithelial electrical resistance associated with an increased paracellular flux of the tracer [{sup 3}H]-mannitol. A concentration-dependent reduction in the expression level of the tight junction constituent claudin-4 was demonstrated by Western blot, which was not due to diminished transcription, increased degradation, or NF-{kappa}B, ERK or JNK activation, and was also observed for a tight junction independent protein, i.e. intestinal alkaline phosphatase. These results demonstrate a dual toxicological effect of DON on differentiated Caco-2 cells consisting in an inhibition of protein synthesis as well as an increase in monolayer permeability, and moreover suggest a possible link between them through diminished synthesis of the tight junction constituent claudin-4.

  8. Escherichia coli challenge and one type of smectite alter intestinal barrier of pigs

    PubMed Central

    2013-01-01

    An experiment was conducted to determine how an E. coli challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs (initial BW: 6.9 ± 1.0 kg) were distributed in a 2 × 4 factorial arrangement of a randomized complete block design (2 challenge treatments: sham or E. coli, and 4 dietary treatments: control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite), with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays (smectite A) tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it. PMID:24359581

  9. Breaking down the barriers: the gut microbiome, intestinal permeability and stress-related psychiatric disorders

    PubMed Central

    Kelly, John R.; Kennedy, Paul J.; Cryan, John F.; Dinan, Timothy G.; Clarke, Gerard; Hyland, Niall P.

    2015-01-01

    The emerging links between our gut microbiome and the central nervous system (CNS) are regarded as a paradigm shift in neuroscience with possible implications for not only understanding the pathophysiology of stress-related psychiatric disorders, but also their treatment. Thus the gut microbiome and its influence on host barrier function is positioned to be a critical node within the brain-gut axis. Mounting preclinical evidence broadly suggests that the gut microbiota can modulate brain development, function and behavior by immune, endocrine and neural pathways of the brain-gut-microbiota axis. Detailed mechanistic insights explaining these specific interactions are currently underdeveloped. However, the concept that a “leaky gut” may facilitate communication between the microbiota and these key signaling pathways has gained traction. Deficits in intestinal permeability may underpin the chronic low-grade inflammation observed in disorders such as depression and the gut microbiome plays a critical role in regulating intestinal permeability. In this review we will discuss the possible role played by the gut microbiota in maintaining intestinal barrier function and the CNS consequences when it becomes disrupted. We will draw on both clinical and preclinical evidence to support this concept as well as the key features of the gut microbiota which are necessary for normal intestinal barrier function. PMID:26528128

  10. Zonulin and its regulation of intestinal barrier function: the biological door to inflammation, autoimmunity, and cancer.

    PubMed

    Fasano, Alessio

    2011-01-01

    The primary functions of the gastrointestinal tract have traditionally been perceived to be limited to the digestion and absorption of nutrients and to electrolytes and water homeostasis. A more attentive analysis of the anatomic and functional arrangement of the gastrointestinal tract, however, suggests that another extremely important function of this organ is its ability to regulate the trafficking of macromolecules between the environment and the host through a barrier mechanism. Together with the gut-associated lymphoid tissue and the neuroendocrine network, the intestinal epithelial barrier, with its intercellular tight junctions, controls the equilibrium between tolerance and immunity to non-self antigens. Zonulin is the only physiological modulator of intercellular tight junctions described so far that is involved in trafficking of macromolecules and, therefore, in tolerance/immune response balance. When the finely tuned zonulin pathway is deregulated in genetically susceptible individuals, both intestinal and extraintestinal autoimmune, inflammatory, and neoplastic disorders can occur. This new paradigm subverts traditional theories underlying the development of these diseases and suggests that these processes can be arrested if the interplay between genes and environmental triggers is prevented by reestablishing the zonulin-dependent intestinal barrier function. This review is timely given the increased interest in the role of a "leaky gut" in the pathogenesis of several pathological conditions targeting both the intestine and extraintestinal organs. PMID:21248165

  11. Dimethyl sulfoxide inhibits zymosan-induced intestinal inflammation and barrier dysfunction

    PubMed Central

    Li, Yu-Meng; Wang, Hai-Bin; Zheng, Jin-Guang; Bai, Xiao-Dong; Zhao, Zeng-Kai; Li, Jing-Yuan; Hu, Sen

    2015-01-01

    AIM: To investigate whether dimethyl sulfoxide (DMSO) inhibits gut inflammation and barrier dysfunction following zymosan-induced systemic inflammatory response syndrome and multiple organ dysfunction syndrome. METHODS: Sprague-Dawley rats were randomly divided into four groups: sham with administration of normal saline (SS group); sham with administration of DMSO (SD group); zymosan with administration of normal saline (ZS group); and zymosan with administration of DMSO (ZD group). Each group contained three subgroups according to 4 h, 8 h, and 24 h after surgery. At 4 h, 8 h, and 24 h after intraperitoneal injection of zymosan (750 mg/kg), the levels of intestinal inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-10] and oxides (myeloperoxidase, malonaldehyde, and superoxide dismutase) were examined. The levels of diamine oxidase (DAO) in plasma and intestinal mucosal blood flow (IMBF) were determined. Intestinal injury was also evaluated using an intestinal histological score and apoptosis of intestinal epithelial cells was determined by deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The intestinal epithelial tight junction protein, ZO-1, was observed by immunofluorescence. RESULTS: DMSO decreased TNF-α and increased IL-10 levels in the intestine compared with the ZS group at the corresponding time points. The activity of intestinal myeloperoxidase in the ZS group was higher than that in the ZD group 24 h after zymosan administration (P < 0.05). DMSO decreased the content of malondialdehyde (MDA) and increased the activity of superoxide dehydrogenase (SOD) 24 h after zymosan administration. The IMBF was lowest at 24 h and was 49.34% and 58.26% in the ZS group and ZD group, respectively (P < 0.05). DMSO alleviated injury in intestinal villi, and the gut injury score was significantly lower than the ZS group (3.6 ± 0.2 vs 4.2 ± 0.3, P < 0.05). DMSO decreased the level of DAO in plasma compared with the ZS

  12. Partial Enteral Nutrition Mitigated Ischemia/Reperfusion-Induced Damage of Rat Small Intestinal Barrier

    PubMed Central

    Wu, Chao; Wang, Xinying; Jiang, Tingting; Li, Chaojun; Zhang, Li; Gao, Xuejin; Tian, Feng; Li, Ning; Li, Jieshou

    2016-01-01

    Background and Aims: This study was designed to investigate a relatively optimum dose of partial enteral nutrition (PEN) which effectively attenuates intestinal barrier dysfunction initiated by ischemia/reperfusion injury (IRI). Methods: In experiment 1, 60 male Sprague-Dawley (SD) rats were subjected to intestinal IRI and assigned to six groups according to the different proportion of EN administrations: namely total parenteral nutrition (TPN or 0%EN), 10%EN, 20%EN, 40%EN, 60%EN, and total enteral nutrition (TEN or 100%) groups, the deficits of intraluminal calorie were supplemented by PN. In experiment 2, 50 male SD rats were subjected to intestinal IRI and divided into five groups based on the results of experiment 1: TPN, TEN, 20%EN, TPN plus pretreatment with NF-κB antagonist 30 min before IRI (TPN+PDTC), and TPN plus pretreatment with HIF-1α antagonist 30 min before IRI (TPN+YC-1) groups. Results: In experiment 1, previous IRI combined with subsequent EN shortage disrupted the structure of intestinal epithelial cell and tight junctions (TJs). While 20% dose of EN had an obviously protective effect on these detrimental consequences. In experiment 2, compared with TPN only, 20%EN exerted a significant protection of barrier function of intestinal epithelium. Analogous results were observed when TPN combined with specific NF-κB/HIF-1α inhibitors (PDTC and YC-1). Meanwhile, the expression of NF-κB/HIF-1α had a similar trend among the groups. Conclusions: Our findings indicate that 20%EN is the minimally effective dosage of EN which promotes the recovery of intestinal barrier function after IRI in a rat model. Furthermore, we discreetly speculate that this benefit is, at least partly, related to NF-κB/HIF-1α pathway expression. PMID:27548209

  13. Impaired function of the intestinal barrier in a novel sub-health rat model

    PubMed Central

    FENG, SISI; LIU, WEIDONG; ZUO, SHENGNAN; XIE, TINGYAN; DENG, HUI; ZHANG, QIUHUAN; ZHONG, BAIYUN

    2016-01-01

    Sub-health is a state featuring a deterioration in physiological function between health and illness, and the sub-health condition has surfaced as life-threatening in humans. The aim of the present study was to establish a sub-health model in rats, and investigate the function of the intestinal barrier in the sub-health rats and rats following intervention. To establish a sub-health model, the rats were subjected to a high-fat and sugar diet, motion restriction and chronic stress. Their serum glucose and triglyceride levels, immune function and adaptability were then measured. The levels of diamine oxidase and D-lactic acid in the plasma were analyzed as markers of the intestinal permeability. The protein and mRNA expression levels of anti-apoptotic YWHAZ in the colonic tissue was detected using immunohistochemical and reverse transcription-quantitative polymerase chain reaction analyses In the present study, the sub-health rat model was successfully established, and sub-health factors increased the intestinal permeability and reduced the expression of YWHAZ. Providing sub-health rats with normal living conditions did not improve the function of the intestinal barrier. In conclusion, the results of the present study demonstrated that intestinal disorders in the sub-health rat model may result from the damage caused by reduce intestinal barrier function as well as the decreased expression levels of YWHAZ. Additionally, rats in the sub-health condition did not recover following subsequent exposure to normal living conditions, suggesting that certain exercises or medical intervention may be necessary to improve sub-health symptoms. PMID:26957295

  14. Glucagon-like peptide-2 protects impaired intestinal mucosal barriers in obstructive jaundice rats

    PubMed Central

    Chen, Jun; Dong, Jia-Tian; Li, Xiao-Jing; Gu, Ye; Cheng, Zhi-Jian; Cai, Yuan-Kun

    2015-01-01

    AIM: To observe the protective effect of glucagon-like peptide-2 (GLP-2) on the intestinal barrier of rats with obstructive jaundice and determine the possible mechanisms of action involved in the protective effect. METHODS: Thirty-six Sprague-Dawley rats were randomly divided into a sham operation group, an obstructive jaundice group, and a GLP-2 group; each group consisted of 12 rats. The GLP-2 group was treated with GLP-2 after the day of surgery, whereas the other two groups were treated with the same concentration of normal saline. Alanine aminotransferase (ALT), total bilirubin, and endotoxin levels were recorded at 1, 3, 7, 10 and 14 d. Furthermore, on the 14th day, body weight, the wet weight of the small intestine, pathological changes of the small intestine and the immunoglobulin A (IgA) expressed by plasma cells located in the small intestinal lamina propria were recorded for each group. RESULTS: In the rat model, jaundice was obvious, and the rats’ activity decreased 4-6 d post bile duct ligation. Compared with the sham operation group, the obstructive jaundice group displayed increased yellow staining of abdominal visceral serosa, decreased small intestine wet weight, thinning of the intestinal muscle layer and villi, villous atrophy, uneven height, fusion, partial villous epithelial cell shedding, substantial inflammatory cell infiltration and significantly reduced IgA expression. However, no significant gross changes were noted between the GLP-2 and sham groups. With time, the levels of ALT, endotoxin and bilirubin in the GLP-2 group were significantly increased compared with the sham group (P < 0.01). The increasing levels of the aforementioned markers were more significant in the obstructive jaundice group than in the GLP-2 group (P < 0.01). CONCLUSION: GLP-2 reduces intestinal mucosal injuries in obstructive jaundice rats, which might be attributed to increased intestinal IgA and reduced bilirubin and endotoxin. PMID:25593463

  15. Barrier protection via Toll-like receptor 2 signaling in porcine intestinal epithelial cells damaged by deoxynivalnol.

    PubMed

    Gu, Min Jeong; Song, Sun Kwang; Lee, In Kyu; Ko, Seongyeol; Han, Seung Eun; Bae, Suhan; Ji, Sang Yun; Park, Byung-Chul; Song, Ki-Duk; Lee, Hak-Kyo; Han, Seung Hyun; Yun, Cheol-Heui

    2016-01-01

    Intestinal barrier is the first line of defense inside the body and comprises intercellular tight junction (TJ) proteins that regulate paracellular permeability. Deoxynivalenol (DON), a fungal metabolite often found in the contaminated food of domestic animals, is known to impair intestinal barrier function and may be involved in intestinal inflammation. Unlike in humans and mice, the importance of Toll-like receptor (TLR) 2 expressed in porcine intestinal epithelial cells is largely unclear. Therefore, the aim of the present study was to investigate whether TLR2 stimulation enhances intestinal barrier function and protects against DON exposure. We found that the cells treated with TLR2 ligands decreased the epithelial barrier permeability and enhanced TJ protein expression in intestinal porcine epithelial cells (IPEC-J2). In addition, pretreatment with TLR2 ligand, including Pam3CSK4 (PCSK) and lipoteichoic acid from Bacillus subtilis, prevented DON-induced barrier dysfunction by increasing the expression of TJ proteins via the PI3K-Akt-dependent pathway. It is likely that the DON-disrupted intestinal barrier caused biological changes of immune cells in the lamina propria. Thus, we conducted co-culture of differentiated IPEC-J2 cells in the upper well together with peripheral blood mononuclear cells in the bottom well and found that apical TLR2 stimulation of IPEC-J2 cells could alleviate the reduction in cell survival and proliferation of immune cells. Conclusively, TLR2 signaling on intestinal epithelial cells may enhance intestinal barrier function and prevent DON-induced barrier dysfunction of epithelial cells. PMID:26857454

  16. Fucoidan enhances intestinal barrier function by upregulating the expression of claudin-1

    PubMed Central

    Iraha, Atsushi; Chinen, Hiroshi; Hokama, Akira; Yonashiro, Takumi; Kinjo, Tetsu; Kishimoto, Kazuto; Nakamoto, Manabu; Hirata, Tetsuo; Kinjo, Nagisa; Higa, Futoshi; Tateyama, Masao; Kinjo, Fukunori; Fujita, Jiro

    2013-01-01

    AIM: To evaluate the protective effects of fucoidan on oxidative stress-induced barrier disruption in human intestinal epithelial cells. METHODS: In Caco-2 cell monolayer models, the disruption of barrier function by oxidative stress is mediated by H2O2. The integrity of polarized Caco-2 cell monolayers was determined by measuring the transepithelial resistance (TER) and permeability was estimated by measuring the paracellular transport of FITC-labeled 4-kDa dextran (FD4). The protective effects of fucoidan on epithelial barrier functions on polarized Caco-2 cell monolayers were evaluated by TER and FD4 flux. The expression of tight junction (TJ) proteins was assessed using reverse-transcription polymerase chain reaction (RT-PCR) and immunofluorescence staining. RESULTS: Without H2O2 treatment, fucoidan significantly increased the TER compared to control (P < 0.05), indicating a direct enhancement of intestinal epithelial barrier function. Next, H2O2 disrupted the epithelial barrier function in a time-dependent manner. Fucoidan prevented the H2O2-induced destruction in a dose-dependent manner. Fucoidan significantly decreased H2O2-induced FD4 flux (P < 0.01), indicating the prevention of disruption in paracellular permeability. RT-PCR showed that Caco-2 cells endogenously expressed claudin-1 and -2, and occludin and that H2O2 reduced the mRNA expression of these TJ proteins. Treatment with fucoidan attenuated the reduction in the expressions of claudin-1 and claudin-2 but not occludin. Immunofluorescence staining revealed that the expression of claudin-1 was intact and high on the cell surface. H2O2 disrupted the integrity of claudin-1. Treatment with fucoidan dramatically attenuated the expression of claudin-1. CONCLUSION: Fucoidan enhanced intestinal epithelial barrier function by upregulating the expression of claudin-1. Thus, fucoidan may be an appropriate therapy for the treatment of inflammatory bowel diseases. PMID:24023493

  17. Early weaning stress impairs development of mucosal barrier function in the porcine intestine

    PubMed Central

    Smith, Feli; Clark, Jessica E.; Overman, Beth L.; Tozel, Christena C.; Huang, Jennifer H.; Rivier, Jean E. F.; Blisklager, Anthony T.

    2010-01-01

    Early life stress is a predisposing factor for the development of chronic intestinal disorders in adult life. Here, we show that stress associated with early weaning in pigs leads to impaired mucosal barrier function. Early weaning (15- to 21-day weaning age) resulted in sustained impairment in intestinal barrier function, as indicated by reductions in jejunal transepithelial electrical resistance and elevations in mucosal-to-serosal flux of paracellular probes [3H]mannitol and [14C]inulin measured at 5 and 9 wk of age, compared with that shown in late-weaned pigs (23- to 28-day weaning age). Elevated baseline short-circuit current was observed in jejunum from early-weaned pigs and was shown to be mediated via enhanced Cl− secretion. Jejunal barrier dysfunction in early-weaned pigs coincided with increased lamina propria immune cell density particularly mucosal mast cells. The mast cell stabilizer drug sodium cromoglycolate ameliorated barrier dysfunction and hypersecretion in early-weaned pigs, demonstrating an important role of mast cells. Furthermore, activation of mast cells ex vivo with c48/80 and corticotrophin-releasing factor (CRF) in pig jejunum mounted in Ussing chambers induced barrier dysfunction and elevations in short-circuit current that were inhibited with mast cell protease inhibitors. Experiments in which selective CRF receptor antagonists were administered to early-weaned pigs revealed that CRF receptor 1 (CRFr1) activation mediates barrier dysfunction and hypersecretion, whereas CRFr2 activation may be responsible for novel protective properties in the porcine intestine in response to early life stress. PMID:19926814

  18. Pathways and Progress in Improving Drug Delivery through the Intestinal Mucosa and Blood-Brain Barriers

    PubMed Central

    Laksitorini, Marlyn; Prasasty, Vivitri D.; Kiptoo, Paul K.; Siahaan, Teruna J.

    2015-01-01

    One of the major hurdles in developing therapeutic agents is the difficulty in delivering drugs through the intestinal mucosa and blood-brain barriers (BBB). The goal here is to describe the general structures of the biological barriers and the strategies to enhance drug delivery across these barriers. Prodrug methods used to improve drug penetration via the transcellular pathway have been successfully developed, and some prodrugs have been used to treat patients. The use of transporters to improve absorption of some drugs (e.g., antiviral agents) has also been successful in treating patients. Other methods, including (a) blocking the efflux pumps to improve transcellular delivery and (b) modulation of cell-cell adhesion in the intercellular junctions to improve paracellular delivery across biological barriers are still in the investigational stage. PMID:25418271

  19. Trophic and cytoprotective nutrition for intestinal adaptation, mucosal repair, and barrier function.

    PubMed

    Ziegler, Thomas R; Evans, Mary E; Fernández-Estívariz, Concepción; Jones, Dean P

    2003-01-01

    Intestinal epithelial cell turnover (proliferation, migration, differentiation, and apoptosis) and gut barrier functions are dynamic processes that are markedly affected by nutritional status, the route of feeding, and the adequacy of specific nutrients in the diet. Emerging studies are defining potential therapeutic roles for specific nutrients and diet-derived compounds (including arginine, glutamate, glutamine, glutathione, glycine, vitamin A, zinc, and specific lipids) in gut mucosal turnover, repair, adaptation after massive bowel resection, and barrier function. The role and regulation of endogenous bowel flora in generating short-chain fatty acids from diet-derived fiber and other diet-derived compounds and the effects of these agents on gut function are increasingly being elucidated. Results of these investigations should define new nutritional methods for trophic and cytoprotective effects on the intestine in conditions such as inflammatory bowel disease, malnutrition, and short bowel syndrome. PMID:12626687

  20. Hypoxia-Inducible Factor 1–Dependent Induction of Intestinal Trefoil Factor Protects Barrier Function during Hypoxia

    PubMed Central

    Furuta, Glenn T.; Turner, Jerrold R.; Taylor, Cormac T.; Hershberg, Robert M.; Comerford, Katrina; Narravula, Sailaja; Podolsky, Daniel K.; Colgan, Sean P.

    2001-01-01

    Mucosal organs such as the intestine are supported by a rich and complex underlying vasculature. For this reason, the intestine, and particularly barrier-protective epithelial cells, are susceptible to damage related to diminished blood flow and concomitant tissue hypoxia. We sought to identify compensatory mechanisms that protect epithelial barrier during episodes of intestinal hypoxia. Initial studies examining T84 colonic epithelial cells revealed that barrier function is uniquely resistant to changes elicited by hypoxia. A search for intestinal-specific, barrier-protective factors revealed that the human intestinal trefoil factor (ITF) gene promoter bears a previously unappreciated binding site for hypoxia-inducible factor (HIF)-1. Hypoxia resulted in parallel induction of ITF mRNA and protein. Electrophoretic mobility shift assay analysis using ITF-specific, HIF-1 consensus motifs resulted in a hypoxia-inducible DNA binding activity, and loading cells with antisense oligonucleotides directed against the α chain of HIF-1 resulted in a loss of ITF hypoxia inducibility. Moreover, addition of anti-ITF antibody resulted in a loss of barrier function in epithelial cells exposed to hypoxia, and the addition of recombinant human ITF to vascular endothelial cells partially protected endothelial cells from hypoxia-elicited barrier disruption. Extensions of these studies in vivo revealed prominent hypoxia-elicited increases in intestinal permeability in ITF null mice. HIF-1–dependent induction of ITF may provide an adaptive link for maintenance of barrier function during hypoxia. PMID:11342587

  1. A Lactobacillus mutant capable of accumulating long-chain polyphosphates that enhance intestinal barrier function.

    PubMed

    Saiki, Asako; Ishida, Yasuaki; Segawa, Shuichi; Hirota, Ryuichi; Nakamura, Takeshi; Kuroda, Akio

    2016-05-01

    Inorganic polyphosphate (polyP) was previously identified as a probiotic-derived substance that enhances intestinal barrier function. PolyP-accumulating bacteria are expected to have beneficial effects on the human gastrointestinal tract. In this study, we selected Lactobacillus paracasei JCM 1163 as a strain with the potential to accumulate polyP, because among the probiotic bacteria stored in our laboratory, it had the largest amount of polyP. The chain length of polyP accumulated in L. paracasei JCM 1163 was approximately 700 phosphate (Pi) residues. L. paracasei JCM 1163 accumulated polyP when Pi was added to Pi-starved cells. We further improved the ability of L. paracasei JCM 1163 to accumulate polyP by nitrosoguanidine mutagenesis. The mutant accumulated polyP at a level of 1500 nmol/mg protein-approximately 190 times that of the wild-type strain. PolyP extracted from the L. paracasei JCM 1163 significantly suppressed the oxidant-induced intestinal permeability in mouse small intestine. In conclusion, we have succeeded in breeding the polyP-accumulating Lactobacillus mutant that is expected to enhance intestinal barrier function. PMID:26966939

  2. Polyphenol-Rich Propolis Extracts Strengthen Intestinal Barrier Function by Activating AMPK and ERK Signaling

    PubMed Central

    Wang, Kai; Jin, Xiaolu; Chen, Yifan; Song, Zehe; Jiang, Xiasen; Hu, Fuliang; Conlon, Michael A.; Topping, David L.

    2016-01-01

    Propolis has abundant polyphenolic constituents and is used widely as a health/functional food. Here, we investigated the effects of polyphenol-rich propolis extracts (PPE) on intestinal barrier function in human intestinal epithelial Caco-2 cells, as well as in rats. In Caco-2 cells, PPE increased transepithelial electrical resistance and decreased lucifer yellow flux. PPE-treated cells showed increased expression of the tight junction (TJ) loci occludin and zona occludens (ZO)-1. Confocal microscopy showed organized expressions in proteins related to TJ assembly, i.e., occludin and ZO-1, in response to PPE. Furthermore, PPE led to the activation of AMPK, ERK1/2, p38, and Akt. Using selective inhibitors, we found that the positive effects of PPE on barrier function were abolished in cells in which AMPK and ERK1/2 signaling were inhibited. Moreover, rats fed a diet supplemented with PPE (0.3% in the diet) exhibited increased colonic epithelium ZO-1 expression. Overall, these data suggest that PPE strengthens intestinal barrier function by activating AMPK and ERK signaling and provide novel insights into the potential application of propolis for human gut health. PMID:27164138

  3. Polyphenol-Rich Propolis Extracts Strengthen Intestinal Barrier Function by Activating AMPK and ERK Signaling.

    PubMed

    Wang, Kai; Jin, Xiaolu; Chen, Yifan; Song, Zehe; Jiang, Xiasen; Hu, Fuliang; Conlon, Michael A; Topping, David L

    2016-01-01

    Propolis has abundant polyphenolic constituents and is used widely as a health/functional food. Here, we investigated the effects of polyphenol-rich propolis extracts (PPE) on intestinal barrier function in human intestinal epithelial Caco-2 cells, as well as in rats. In Caco-2 cells, PPE increased transepithelial electrical resistance and decreased lucifer yellow flux. PPE-treated cells showed increased expression of the tight junction (TJ) loci occludin and zona occludens (ZO)-1. Confocal microscopy showed organized expressions in proteins related to TJ assembly, i.e., occludin and ZO-1, in response to PPE. Furthermore, PPE led to the activation of AMPK, ERK1/2, p38, and Akt. Using selective inhibitors, we found that the positive effects of PPE on barrier function were abolished in cells in which AMPK and ERK1/2 signaling were inhibited. Moreover, rats fed a diet supplemented with PPE (0.3% in the diet) exhibited increased colonic epithelium ZO-1 expression. Overall, these data suggest that PPE strengthens intestinal barrier function by activating AMPK and ERK signaling and provide novel insights into the potential application of propolis for human gut health. PMID:27164138

  4. Mycotoxins Deoxynivalenol and Fumonisins Alter the Extrinsic Component of Intestinal Barrier in Broiler Chickens.

    PubMed

    Antonissen, Gunther; Van Immerseel, Filip; Pasmans, Frank; Ducatelle, Richard; Janssens, Geert P J; De Baere, Siegrid; Mountzouris, Konstantinos C; Su, Shengchen; Wong, Eric A; De Meulenaer, Bruno; Verlinden, Marc; Devreese, Mathias; Haesebrouck, Freddy; Novak, Barbara; Dohnal, Ilse; Martel, An; Croubels, Siska

    2015-12-23

    Deoxynivalenol (DON) and fumonisins (FBs) are secondary metabolites produced by Fusarium fungi that frequently contaminate broiler feed. The aim of this study was to investigate the impact of DON and/or FBs on the intestinal barrier in broiler chickens, more specifically on the mucus layer and antioxidative response to oxidative stress. One-day-old broiler chicks were divided into four groups, each consisting of eight pens of seven birds each, and were fed for 15 days either a control diet, a DON-contaminated diet (4.6 mg DON/kg feed), a FBs-contaminated diet (25.4 mg FB1 + FB2/kg feed), or a DON+FBs-contaminated diet (4.3 mg DON and 22.9 mg FB1 + FB2/kg feed). DON and FBs affected the duodenal mucus layer by suppressing intestinal mucin (MUC) 2 gene expression and altering the mucin monosaccharide composition. Both mycotoxins decreased gene expression of the intestinal zinc transporter (ZnT)-1 and regulated intracellular methionine homeostasis, which are both important for preserving the cell's critical antioxidant activity. Feeding a DON- and/or FBs-contaminated diet, at concentrations close to the European Union maximum guidance levels (5 mg DON and 20 mg FB1 + FB2/kg feed) changes the intestinal mucus layer and several intestinal epithelial antioxidative mechanisms. PMID:26632976

  5. Delivery of a mucin domain enriched in cysteine residues strengthens the intestinal mucous barrier.

    PubMed

    Gouyer, Valérie; Dubuquoy, Laurent; Robbe-Masselot, Catherine; Neut, Christel; Singer, Elisabeth; Plet, Ségolène; Geboes, Karel; Desreumaux, Pierre; Gottrand, Frédéric; Desseyn, Jean-Luc

    2015-01-01

    A weakening of the gut mucous barrier permits an increase in the access of intestinal luminal contents to the epithelial cells, which will trigger the inflammatory response. In inflammatory bowel diseases, there is an inappropriate and ongoing activation of the immune system, possibly because the intestinal mucus is less protective against the endogenous microflora. General strategies aimed at improving the protection of the intestinal epithelium are still missing. We generated a transgenic mouse that secreted a molecule consisting of 12 consecutive copies of a mucin domain into its intestinal mucus, which is believed to modify the mucus layer by establishing reversible interactions. We showed that the mucus gel was more robust and that mucin O-glycosylation was altered. Notably, the gut epithelium of transgenic mice housed a greater abundance of beneficial Lactobacillus spp. These modifications were associated with a reduced susceptibility of transgenic mice to chemically induced colitis. Furthermore, transgenic mice cleared faster Citrobacter rodentium bacteria which were orally given and mice were more protected against bacterial translocation induced by gavage with adherent-invasive Escherichia coli. Our data show that delivering the mucin CYS domain into the gut lumen strengthens the intestinal mucus blanket which is impaired in inflammatory bowel diseases. PMID:25974250

  6. Delivery of a mucin domain enriched in cysteine residues strengthens the intestinal mucous barrier

    PubMed Central

    Gouyer, Valérie; Dubuquoy, Laurent; Robbe-Masselot, Catherine; Neut, Christel; Singer, Elisabeth; Plet, Ségolène; Geboes, Karel; Desreumaux, Pierre; Gottrand, Frédéric; Desseyn, Jean-Luc

    2015-01-01

    A weakening of the gut mucous barrier permits an increase in the access of intestinal luminal contents to the epithelial cells, which will trigger the inflammatory response. In inflammatory bowel diseases, there is an inappropriate and ongoing activation of the immune system, possibly because the intestinal mucus is less protective against the endogenous microflora. General strategies aimed at improving the protection of the intestinal epithelium are still missing. We generated a transgenic mouse that secreted a molecule consisting of 12 consecutive copies of a mucin domain into its intestinal mucus, which is believed to modify the mucus layer by establishing reversible interactions. We showed that the mucus gel was more robust and that mucin O-glycosylation was altered. Notably, the gut epithelium of transgenic mice housed a greater abundance of beneficial Lactobacillus spp. These modifications were associated with a reduced susceptibility of transgenic mice to chemically induced colitis. Furthermore, transgenic mice cleared faster Citrobacter rodentium bacteria which were orally given and mice were more protected against bacterial translocation induced by gavage with adherent–invasive Escherichia coli. Our data show that delivering the mucin CYS domain into the gut lumen strengthens the intestinal mucus blanket which is impaired in inflammatory bowel diseases. PMID:25974250

  7. Activation of muscarinic cholinoceptor ameliorates tumor necrosis factor-α-induced barrier dysfunction in intestinal epithelial cells.

    PubMed

    Khan, Md Rafiqul Islam; Uwada, Junsuke; Yazawa, Takashi; Islam, Md Tariqul; Krug, Susanne M; Fromm, Michael; Karaki, Shin-ichiro; Suzuki, Yuichi; Kuwahara, Atsukazu; Yoshiki, Hatsumi; Sada, Kiyonao; Muramatsu, Ikunobu; Anisuzzaman, Abu Syed Md; Taniguchi, Takanobu

    2015-11-30

    Impaired intestinal barrier function is one of the critical issues in inflammatory bowel diseases. The aim of this study is to investigate muscarinic cholinoceptor (mAChR)-mediated signaling for the amelioration of cytokine-induced barrier dysfunction in intestinal epithelium. Rat colon challenged with TNF-α and interferon γ reduced transepithelial electrical resistance (TER). This barrier injury was attenuated by muscarinic stimulation. In HT-29/B6 intestinal epithelial cells, muscarinic stimulation suppressed TNF-α-induced activation of NF-κB signaling and barrier disruption. Finally, muscarinic stimulation promoted the shedding of TNFR1, which would be a mechanism for the attenuation of TNF-α/NF-κB signaling and barrier disruption via mAChR. PMID:26519558

  8. Role of regenerating gene I in claudin expression and barrier function in the small intestine.

    PubMed

    Kitayama, Yoshitaka; Fukui, Hirokazu; Hara, Ken; Eda, Hirotsugu; Kodani, Mio; Yang, Mo; Sun, Chao; Yamagishi, Hidetsugu; Tomita, Toshihiko; Oshima, Tadayuki; Watari, Jiro; Takasawa, Shin; Miwa, Hiroto

    2016-07-01

    We have recently shown that loss of the regenerating gene (Reg) I causes susceptibility to nonsteroidal anti-inflammatory drug-induced gastrointestinal damage. However, the mechanism by which Reg I plays a protective role against this pathophysiological condition is unclear. Here, we investigated whether Reg I plays roles in the induction of tight junction proteins and mucosal barrier function in the small intestine. The small-intestinal permeability was evaluated in Reg I-deficient mice by FITC-dextran and transepithelial electrical resistance (TEER) assay. The effect of REG Iα on TEER, claudins expression, and intracellular signaling was examined using Caco2 cells in vitro. Small-intestinal expression of claudins 3 and 4 was investigated in Reg I-deficient mice in vivo. REG I deficiency significantly decreased the expression of claudin 3 in the small-intestinal epithelium. When mice were treated with indomethacin, the serum level of FITC-dextran in Reg I knockout mice was significantly higher than that in wild-type (WT) mice. The level of small-intestinal TEER was significantly decreased in Reg I knockout mice compared with WT mice under normal condition. REG Iα stimulation significantly enhanced the level of TEER in Caco2 cells. Treatment with REG Iα enhanced the expression of claudins 3 and 4 and promoted Sp1, Akt, and ERK phosphorylation in Caco2 cells, whereas these effects were attenuated by treatment with anti-REG Iα antibody. Reg I may play a role in the maintenance of mucosal barrier function by inducing tight junction proteins such as claudins 3 and 4. PMID:27055226

  9. Boswellia serrata Preserves Intestinal Epithelial Barrier from Oxidative and Inflammatory Damage.

    PubMed

    Catanzaro, Daniela; Rancan, Serena; Orso, Genny; Dall'Acqua, Stefano; Brun, Paola; Giron, Maria Cecilia; Carrara, Maria; Castagliuolo, Ignazio; Ragazzi, Eugenio; Caparrotta, Laura; Montopoli, Monica

    2015-01-01

    Aminosalicylates, corticosteroids and immunosuppressants are currently the therapeutic choices in inflammatory bowel diseases (IBD), however, with limited remission and often serious side effects. Meanwhile complementary and alternative medicine (CAM) use is increasing, particularly herbal medicine. Boswellia serrata is a traditional Ayurvedic remedy with anti-inflammatory properties, of interest for its usefulness in IBDs. The mechanism of this pharmacological potential of Boswellia serrata was investigated in colonic epithelial cell monolayers exposed to H2O2 or INF-γ+TNF-α, chosen as in vitro experimental model of intestinal inflammation. The barrier function was evaluated by the transepithelial electrical resistance (TEER) and paracellular permeability assay, and by the tight junction proteins (zonula occludens-1, ZO-1 and occludin) immunofluorescence. The expression of phosphorylated NF-κB and reactive oxygen species (ROS) generation were determined by immunoblot and cytofluorimetric assay, respectively. Boswellia serrata oleo-gum extract (BSE) and its pure derivative acetyl-11-keto-β-boswellic acid (AKBA), were tested at 0.1-10 μg/ml and 0.027 μg/ml, respectively. BSE and AKBA safety was demonstrated by no alteration of intestinal cell viability and barrier function and integrity biomarkers. H2O2 or INF-γ+TNF-α treatment of Caco-2 cell monolayers significantly reduced TEER, increased paracellular permeability and caused the disassembly of tight junction proteins occludin and ZO-1. BSE and AKBA pretreatment significantly prevented functional and morphological alterations and also the NF-κB phosphorylation induced by the inflammatory stimuli. At the same concentrations BSE and AKBA counteracted the increase of ROS caused by H2O2 exposure. Data showed the positive correlation of the antioxidant activity with the mechanism involved in the physiologic maintenance of the integrity and function of the intestinal epithelium. This study elucidates the

  10. Autophagy in alcohol-induced liver diseases.

    PubMed

    Dolganiuc, Angela; Thomes, Paul G; Ding, Wen-Xing; Lemasters, John J; Donohue, Terrence M

    2012-08-01

    Alcohol is the most abused substance worldwide and a significant source of liver injury; the mechanisms of alcohol-induced liver disease are not fully understood. Significant cellular toxicity and impairment of protein synthesis and degradation occur in alcohol-exposed liver cells, along with changes in energy balance and modified responses to pathogens. Autophagy is the process of cellular catabolism through the lysosomal-dependent machinery, which maintains a balance among protein synthesis, degradation, and recycling of self. Autophagy is part of normal homeostasis and it can be triggered by multiple factors that threaten cell integrity, including starvation, toxins, or pathogens. Multiple factors regulate autophagy; survival and preservation of cellular integrity at the expense of inadequately folded proteins and damaged high-energy generating intracellular organelles are prominent targets of autophagy in pathological conditions. Coincidentally, inadequately folded proteins accumulate and high-energy generating intracellular organelles, such as mitochondria, are damaged by alcohol abuse; these alcohol-induced pathological findings prompted investigation of the role of autophagy in the pathogenesis of alcohol-induced liver damage. Our review summarizes the current knowledge about the role and implications of autophagy in alcohol-induced liver disease. PMID:22551004

  11. Alcohol-Induced Disruption of Endocrine Signaling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article contains the proceedings of a symposium at the 2006 ISBRA Meeting in Sydney Australia, organized and co-chaired by Martin J. Ronis and Thomas M. Badger. The presentations were (1) Effects of long term ethanol consumption on liver injury and repair, by Jack R. Wands; (2) Alcohol-induced...

  12. Effects of Soybean Agglutinin on Intestinal Barrier Permeability and Tight Junction Protein Expression in Weaned Piglets

    PubMed Central

    Zhao, Yuan; Qin, Guixin; Sun, Zewei; Che, Dongsheng; Bao, Nan; Zhang, Xiaodong

    2011-01-01

    This study was developed to provide further information on the intestinal barrier permeability and the tight junction protein expression in weaned piglets fed with different levels of soybean agglutinin (SBA). Twenty-five weaned crossbred barrows (Duroc × Landrace × Yorkshire) were selected and randomly allotted to five groups, each group with five replicates. The piglets in the control group were not fed with leguminous products. 0.05, 0.1, 0.15 and 0.2% SBA was added to the control diet to form four experimental diets, respectively. After the experimental period of 7 days (for each group), all the piglets were anesthetized with excess procaine and slaughtered. The d-lactic acid in plasma and the Ileal mucosa diamine oxidase (DAO) was analyzed to observe the change in the intestinal permeability. The tight junction proteins occludin and ZO-1 in the jejunum tissue distribution and relative expression were detected by immunohistochemistry and Western Blot. The results illustrated that a high dose of SBA (0.1–0.2%) could increase the intestinal permeability and reduce piglet intestinal epithelial tight junction protein occludin or ZO-1 expression, while low dose of SBA (0.05% of total diet) had no significant affects. The contents of DAO, d-lactic acid, occludin or ZO-1, had a linear relationship with the SBA levels (0–0.2%) in diets. The high dose SBA (0.1–0.2%) could increase the intestinal permeability and reduce piglet intestinal epithelial tight junction protein occludin or ZO-1 expression, while low dose of SBA (0.05% of total diet) had no affects. PMID:22272087

  13. Intestinal hypoperfusion contributes to gut barrier failure in severe acute pancreatitis.

    PubMed

    Rahman, Sakhawat H; Ammori, Basil J; Holmfield, John; Larvin, Michael; McMahon, Michael J

    2003-01-01

    Intestinal barrier failure and subsequent bacterial translocation have been implicated in the development of organ dysfunction and septic complications associated with severe acute pancreatitis. Splanchnic hypoperfusion and ischemia/reperfusion injury have been postulated as a cause of increased intestinal permeability. The urinary concentration of intestinal fatty acid binding protein (IFABP) has been shown to be a sensitive marker of intestinal ischemia, with increased levels being associated with ischemia/reperfusion. The aim of the current study was to assess the relationship between excretion of IFABP in urine, gut mucosal barrier failure (intestinal hyperpermeability and systemic exposure to endotoxemia), and clinical severity. Patients with a clinical and biochemical diagnosis of acute pancreatitis were studied within 72 hours of onset of pain. Polyethylene glycol probes of 3350 kDa and 400 kDa were administered enterally, and the ratio of the percentage of retrieval of each probe after renal excretion was used as a measure of intestinal macromolecular permeability. Collected urine was also used to determine the IFABP concentration (IFABP-c) and total IFABP (IFABP-t) excreted over the 24-hour period, using an enzyme-linked immunosorbent assay technique. The systemic inflammatory response was estimated from peak 0 to 72-hour plasma C-reactive protein levels, and systemic exposure to endotoxins was measured using serum IgM endotoxin cytoplasmic antibody (EndoCAb) levels. The severity of the attack was assessed on the basis of the Atlanta criteria. Sixty-one patients with acute pancreatitis (severe in 19) and 12 healthy control subjects were studied. Compared to mild attacks, severe attacks were associated with significantly higher urinary IFABP-c (median 1092 pg/ml vs. 84 pg/ml; P < 0.001) and IFABP-t (median 1.14 microg vs. 0.21 microg; P = 0.003). Furthermore, the control group had significantly lower IFABP-c (median 37 pg/ml; P = 0.029) and IFABP-t (median

  14. Ursodeoxycholic acid ameliorates experimental ileitis counteracting intestinal barrier dysfunction and oxidative stress.

    PubMed

    Bernardes-Silva, Carlos Felipe; Damião, Adérson O M C; Sipahi, Aytan M; Laurindo, Francisco R M; Iriya, Kiyoshi; Lopasso, Fabio P; Buchpiguel, Carlos A; Lordello, Maria Laura L; Agostinho, Carmem L O; Laudanna, Antonio A

    2004-10-01

    The aim of this study was to evaluate the effect of ursodeoxycholic acid (UDCA) on intestinal permeability (IP) and reactive oxygen species (ROS) generation in indomethacin-induced enteropathy, a well-known experimental model of Crohn's disease. Seventy-eight male Wistar rats were randomly assigned to receive indomethacin, indomethacin + UDCA, or vehicles. Indomethacin induced a significant increase in the fraction of urinary excretion of 51Cr-EDTA following oral administration (7.9 +/- 1.3 vs 2.3 +/- 0.2%; P < 0.05) and lucigenin-amplified chemiluminescence in intestinal fragments ex vivo (10.1 +/- 1.9 vs 2.6 +/- 0.4 cpm x 10(3)/mg; P < 0.05) compared to controls. UDCA significantly reversed these effects (P < 0.05), without being incorporated in biliary bile acid composition (HPLC analysis). These findings support a local protective effect of UDCA in experimental ileitis by the modulation of intestinal barrier dysfunction and oxidative stress. In short, they provide insights into mechanisms of action of UDCA in intestinal inflammation and a new perspective on the treatment of Crohn's disease. PMID:15573906

  15. Lactobacillus protects the integrity of intestinal epithelial barrier damaged by pathogenic bacteria

    PubMed Central

    Yu, Qinghua; Yuan, Lixia; Deng, Jun; Yang, Qian

    2015-01-01

    Pathogens invade intestinal mucosal barrier through phagocytosis of antigen presenting cells (dendritic cell, microfold cells), or through the invasion into the intestinal epithelial directly. Some pathogens could damage the cell junction between epithelial cells and use the paracellular pathway as an entrance to invade. Moreover, some Lactobacillus could inhibit the adhesion of the pathogens and protect the integrity of the cell junction and mucosal barrier. This research focused on the potential therapeutic effect of Lactobacillus fructosus (L. fructosus) C2 to attenuate ETEC K88 or S. typhimurium SL1344 induced changes to mucosal barrier. The results demonstrated that treatment of polarized Caco-2 cells with L. fructosus C2 reduced the permeation of dextran, and expression of IL-8, p-ERK, and p-JNK when cells were infected with pathogenic bacteria. The findings indicated that L. fructosus C2 exerted a protective effect against the damage to the integrity of Caco-2 cells by ETEC or S. typhimurium infection. PMID:25859435

  16. Checkpoint Kinase 1 Activation Enhances Intestinal Epithelial Barrier Function via Regulation of Claudin-5 Expression

    PubMed Central

    Watari, Akihiro; Hasegawa, Maki; Yagi, Kiyohito; Kondoh, Masuo

    2016-01-01

    Several stressors are known to influence epithelial tight junction (TJ) integrity, but the association between DNA damage and TJ integrity remains unclear. Here we examined the effects of daunorubicin and rebeccamycin, two anti-tumor chemicals that induce DNA damage, on TJ integrity in human intestinal epithelial cells. Daunorubicin and rebeccamycin dose-dependently enhanced transepithelial electrical resistance (TER) and decreased flux of the 4 kDa FITC-dextran in Caco-2 cell monolayer. Daunorubicin- or rebeccamycin-induced enhancement of the TJ barrier function partly rescued attenuation of the barrier function by the inflammatory cytokines TNF-α and IFN-γ. Daunorubicin and rebeccamycin increased claudin-5 expression and the product was distributed in the actin cytoskeleton fraction, which was enriched with TJ proteins. Caffeine, which is an inhibitor of ataxia telangiectasia mutated protein (ATM) and ataxia telangiectasia mutated and Rad3-related protein (ATR), and the Chk1 inhibitor inhibited the TER increases induced by daunorubicin and rebeccamycin, whereas a Chk2 inhibitor did not. Treatment with Chk1 siRNA also significantly inhibited the TER increases. Induction of claudin-5 expression was inhibited by Chk1 inhibitor and by siRNA treatment. Our results suggest that Chk1 activation by daunorubicin and rebeccamycin induced claudin-5 expression and enhanced TJ barrier function in Caco-2 cell monolayer, which suggests a link between DNA damage and TJ integrity in the human intestine. PMID:26727128

  17. Intestinal barrier dysfunction: implications for chronic inflammatory conditions of the bowel.

    PubMed

    Miner-Williams, Warren M; Moughan, Paul J

    2016-06-01

    The intestinal epithelium of adult humans acts as a differentially permeable barrier that separates the potentially harmful contents of the lumen from the underlying tissues. Any dysfunction of this boundary layer that disturbs the homeostatic equilibrium between the internal and external environments may initiate and sustain a biochemical cascade that results in inflammation of the intestine. Key to such dysfunction are genetic, microbial and other environmental factors that, singularly or in combination, result in chronic inflammation that is symptomatic of inflammatory bowel disease (IBD). The aim of the present review is to assess the scientific evidence to support the hypothesis that defective transepithelial transport mechanisms and the heightened absorption of intact antigenic proinflammatory oligopeptides are important contributing factors in the pathogenesis of IBD. PMID:27087106

  18. The epithelial barrier is maintained by in vivo tight junction expansion during pathologic intestinal epithelial shedding

    PubMed Central

    Marchiando, Amanda M.; Shen, Le; Graham, W. Vallen; Edelblum, Karen L.; Duckworth, Carrie A.; Guan, Yanfang; Montrose, Marshall H.; Turner, Jerrold R.; Watson, Alastair J.M.

    2011-01-01

    BACKGROUND & AIMS Tumor necrosis factor (TNF) increases intestinal epithelial cell shedding and apoptosis, potentially challenging the barrier between the gastrointestinal lumen and internal tissues. We investigated the mechanism of tight junction remodeling and barrier maintenance, as well as the roles of cytoskeletal regulatory molecules during TNF-induced shedding. METHODS We studied wild-type and transgenic mice that express the fluorescent-tagged proteins enhanced green fluorescent protein–occludin or monomeric red fluorescent protein1–ZO-1. After injection of high doses of TNF (7.5µg, i.p.), laparotomies were performed and segments of small intestine were opened to visualize the mucosa by video confocal microscopy. Pharmacologic inhibitors and knockout mice were used to determine the roles of caspase activation, actomyosin, and microtubule remodeling and membrane trafficking in epithelial shedding. RESULTS Changes detected included redistribution of the tight junction proteins ZO-1 and occluding to lateral membranes of shedding cells. These proteins ultimately formed a funnel around the shedding cell that defined the site of barrier preservation. Claudins, E-cadherin, F-actin, myosin II, Rho-associated kinase (ROCK), and myosin light chain kinase (MLCK) were also recruited to lateral membranes. Caspase activity, myosin motor activity, and microtubules were required to initiate shedding, whereas completion of the process required microfilament remodeling and ROCK, MLCK, and dynamin II activities. CONCLUSIONS Maintenance of the epithelial barrier during TNF-induced cell shedding is a complex process that involves integration of microtubules, microfilaments, and membrane traffic to remove apoptotic cells. This process is accompanied by redistribution of apical junctional complex proteins to form intercellular barriers between lateral membranes and maintain mucosal function. PMID:21237166

  19. Methyl donor deficiency affects small-intestinal differentiation and barrier function in rats.

    PubMed

    Bressenot, Aude; Pooya, Shabnam; Bossenmeyer-Pourie, Carine; Gauchotte, Guillaume; Germain, Adeline; Chevaux, Jean-Baptiste; Coste, Florence; Vignaud, Jean-Michel; Guéant, Jean-Louis; Peyrin-Biroulet, Laurent

    2013-02-28

    Dietary methyl donors and their genetic determinants are associated with Crohn's disease risk. We investigated whether a methyl-deficient diet (MDD) may affect development and functions of the small intestine in rat pups from dams subjected to the MDD during gestation and lactation. At 1 month before pregnancy, adult females were fed with either a standard food or a diet without vitamin B12, folate and choline. A global wall hypotrophy was observed in the distal small bowel (MDD animals 0·30 mm v. controls 0·58 mm; P< 0·001) with increased crypt apoptosis (3·37 v. 0·4%; P< 0·001), loss of enterocyte differentiation in the villus and a reduction in intestinal alkaline phosphatase production. Cleaved caspase-3 immunostaining (MDD animals 3·37% v. controls 0·4%, P< 0·001) and the Apostain labelling index showed increased crypt apoptosis (3·5 v. 1·4%; P= 0·018). Decreased proliferation was observed in crypts of the proximal small bowel with a reduced number of minichromosome maintenance 6 (MDD animals 52·83% v. controls 83·17%; P= 0·048) and proliferating cell nuclear antigen-positive cells (46·25 v. 59 %; P= 0·05). This lack of enterocyte differentiation in the distal small bowel was associated with an impaired expression of β-catenin and a decreased β-catenin-E-cadherin interaction. The MDD affected the intestinal barrier in the proximal small bowel by decreasing Paneth cell number after immunostaining for lysosyme (MDD animals 8·66% v. controls 21·66%) and by reducing goblet cell number and mucus production after immunostaining for mucin-2 (crypts 8·66 v. 15·33%; villus 7 v. 17%). The MDD has dual effects on the small intestine by producing dramatic effects on enterocyte differentiation and barrier function in rats. PMID:22794784

  20. Stress-induced breakdown of intestinal barrier function in the rat: reversal by wood creosote.

    PubMed

    Kuge, Tomoo; Greenwood-Van Meerveld, Beverley; Sokabe, Masahiro

    2006-07-24

    Our previous studies demonstrated that wood creosote (Seirogan) inhibits intestinal secretion and normalizes the transport of electrolytes and water in rats subjected to restraint stress. The goal of the present study was to examine whether wood creosote has a protective effect against stress-induced breakdown of intestinal barrier function. F-344 rats were subjected to 90-min water avoidance stress (WAS) with wood creosote (30 mg/kg) or vehicle administered intragastrically 30 min prior to WAS. Sham stressed rats received wood creosote or vehicle treatment but did not experience the WAS. All rats were euthanized at the end of the WAS or sham-stress and the jejunum and colon were isolated. Epithelial transport was studied in modified Ussing chambers. Spontaneous secretion was assessed by electrophysiological measurement of the short circuit current (I(sc)) while electrical conductance (G) was calculated from the potential difference (PD) and I(sc) using Ohm's law. Intestinal permeability was defined by the mucosal-to-serosal flux of horseradish peroxidase (HRP). WAS significantly elevated basal I(sc) and G and increased epithelial permeability to HRP in the jejunum but not in the colon. Wood creosote resulted in a significant reduction of the stress-induced increase in I(sc), G and the mucosal-to-serosal flux of HRP compared to the vehicle-treated group. Wood creosote caused no significant effects in sham-stressed rats. The results suggest that oral administration of wood creosote may prevent stress-induced diarrhea by preventing aversive effects on small intestinal secretion and barrier function. PMID:16643959

  1. CXCR4 Antagonist AMD3100 Modulates Claudin Expression and Intestinal Barrier Function in Experimental Colitis

    PubMed Central

    Xia, Xian-Ming; Wang, Fang-Yu; Zhou, Ju; Hu, Kai-Feng; Li, Su-Wen; Zou, Bing-Bing

    2011-01-01

    Ulcerative colitis is a gastrointestinal disorder characterized by local inflammation and impaired epithelial barrier. Previous studies demonstrated that CXC chemokine receptor 4 (CXCR4) antagonists could reduce colonic inflammation and mucosal damage in dextran sulfate sodium (DSS)-induced colitis. Whether CXCR4 antagonist has action on intestinal barrier and the possible mechanism, is largely undefined. In the present study, the experimental colitis was induced by administration of 5% DSS for 7 days, and CXCR4 antagonist AMD3100 was administered intraperitoneally once daily during the study period. For in vitro study, HT-29/B6 colonic cells were treated with cytokines or AMD3100 for 24 h until assay. DSS-induced colitis was characterized by morphologic changes in mice. In AMD3100-treated mice, epithelial destruction, inflammatory infiltration, and submucosal edema were markedly reduced, and the disease activity index was also significantly decreased. Increased intestinal permeability in DSS-induced colitis was also significantly reduced by AMD3100. The expressions of colonic claudin-1, claudin-3, claudin-5, claudin-7 and claudin-8 were markedly decreased after DSS administration, whereas colonic claudin-2 expression was significantly decreased. Treatment with AMD3100 prevented all these changes. However, AMD3100 had no influence on claudin-3, claudin-5, claudin-7 and claudin-8 expression in HT-29/B6 cells. Cytokines as TNF-α, IL-6, and IFN-γ increased apoptosis and monolayer permeability, inhibited the wound-healing and the claudin-3, claudin-7 and claudin-8 expression in HT-29/B6 cells. We suggest that AMD3100 acted on colonic claudin expression and intestinal barrier function, at least partly, in a cytokine-dependent pathway. PMID:22073304

  2. The feed contaminant deoxynivalenol affects the intestinal barrier permeability through inhibition of protein synthesis.

    PubMed

    Awad, Wageha A; Zentek, Jürgen

    2015-06-01

    Deoxynivalenol (DON) has critical health effects if the contaminated grains consumed by humans or animals. DON can have negative effects on the active transport of glucose and amino acids in the small intestine of chickens. As the underlying mechanisms are not fully elucidated, the present study was performed to delineate more precisely the effects of cycloheximide (protein synthesis inhibitor, CHX) and DON on the intestinal absorption of nutrients. This was to confirm whether DON effects on nutrient absorption are due to an inhibition of protein synthesis. Changes in ion transport and barrier function were assessed by short-circuit current (Isc) and transepithelial ion conductance (Gt) in Ussing chambers. Addition of D-glucose or L-glutamine to the luminal side of the isolated mucosa of the jejunum increased (P < 0.001) the Isc compared with basal conditions in the control tissues. However, the Isc was not increased by the glucose or glutamine addition after pre-incubation of tissues with DON or CHX. Furthermore, both DON and CHX reduced Gt, indicating that the intestinal barrier is compromised and consequently induced a greater impairment of the barrier function. The remarkable similarity between the activity of CHX and DON on nutrient uptake is consistent with their common ability to inhibit protein synthesis. It can be concluded that the decreases in transport activity by CHX was evident in this study using the chicken as experimental model. Similarly, DON has negative effects on the active transport of some nutrients, and these can be explained by its influence on protein synthesis. PMID:24888376

  3. Claudin-3 expression in radiation-exposed rat models: A potential marker for radiation-induced intestinal barrier failure

    SciTech Connect

    Shim, Sehwan; Lee, Jong-geol; Bae, Chang-hwan; Lee, Seung Bum; Jang, Won-Suk; Lee, Sun-Joo; Lee, Seung-Sook; Park, Sunhoo

    2015-01-02

    Highlights: • Irradiation increased intestinal bacterial translocation, accompanied by claudin protein expression in rats. • Neurotensin decreased the bacterial translocation and restored claudin-3 expression. • Claudin-3 can be used as a marker in evaluating radiation induced intestinal injury. - Abstract: The molecular events leading to radiation-induced intestinal barrier failure are not well known. The influence of the expression of claudin proteins in the presence and absence of neurotensin was investigated in radiation-exposed rat intestinal epithelium. Wistar rats were randomly divided into control, irradiation, and irradiation + neurotensin groups, and bacterial translocation to the mesenteric lymph node and expression of claudins were determined. Irradiation led to intestinal barrier failure as demonstrated by significant bacterial translocation. In irradiated terminal ilea, expression of claudin-3 and claudin-4 was significantly decreased, and claudin-2 expression was increased. Administration of neurotensin significantly reduced bacterial translocation and restored the structure of the villi as seen by histologic examination. Among the three subtype of claudins, only claudin-3 expression was restored. These results suggest that the therapeutic effect of neurotensin on the disruption of the intestinal barrier is associated with claudin-3 alteration and that claudin-3 could be used as a marker in evaluating radiation-induced intestinal injury.

  4. Glycoprotein A33 deficiency: a new mouse model of impaired intestinal epithelial barrier function and inflammatory disease.

    PubMed

    Williams, Benjamin B; Tebbutt, Niall C; Buchert, Michael; Putoczki, Tracy L; Doggett, Karen; Bao, Shisan; Johnstone, Cameron N; Masson, Frederick; Hollande, Frederic; Burgess, Antony W; Scott, Andrew M; Ernst, Matthias; Heath, Joan K

    2015-08-01

    The cells of the intestinal epithelium provide a selectively permeable barrier between the external environment and internal tissues. The integrity of this barrier is maintained by tight junctions, specialised cell-cell contacts that permit the absorption of water and nutrients while excluding microbes, toxins and dietary antigens. Impairment of intestinal barrier function contributes to multiple gastrointestinal disorders, including food hypersensitivity, inflammatory bowel disease (IBD) and colitis-associated cancer (CAC). Glycoprotein A33 (GPA33) is an intestinal epithelium-specific cell surface marker and member of the CTX group of transmembrane proteins. Roles in cell-cell adhesion have been demonstrated for multiple CTX family members, suggesting a similar function for GPA33 within the gastrointestinal tract. To test a potential requirement for GPA33 in intestinal barrier function, we generated Gpa33(-/-) mice and subjected them to experimental regimens designed to produce food hypersensitivity, colitis and CAC. Gpa33(-/-) mice exhibited impaired intestinal barrier function. This was shown by elevated steady-state immunosurveillance in the colonic mucosa and leakiness to oral TRITC-labelled dextran after short-term exposure to dextran sodium sulphate (DSS) to injure the intestinal epithelium. Gpa33(-/-) mice also exhibited rapid onset and reduced resolution of DSS-induced colitis, and a striking increase in the number of colitis-associated tumours produced by treatment with the colon-specific mutagen azoxymethane (AOM) followed by two cycles of DSS. In contrast, Gpa33(-/-) mice treated with AOM alone showed no increase in sporadic tumour formation, indicating that their increased tumour susceptibility is dependent on inflammatory stimuli. Finally, Gpa33(-/-) mice displayed hypersensitivity to food allergens, a common co-morbidity in humans with IBD. We propose that Gpa33(-/-) mice provide a valuable model to study the mechanisms linking intestinal

  5. Bifidobacteria Prevent Tunicamycin-Induced Endoplasmic Reticulum Stress and Subsequent Barrier Disruption in Human Intestinal Epithelial Caco-2 Monolayers.

    PubMed

    Akiyama, Takuya; Oishi, Kenji; Wullaert, Andy

    2016-01-01

    Endoplasmic reticulum (ER) stress is caused by accumulation of unfolded and misfolded proteins in the ER, thereby compromising its vital cellular functions in protein production and secretion. Genome wide association studies in humans as well as experimental animal models linked ER stress in intestinal epithelial cells (IECs) with intestinal disorders including inflammatory bowel diseases. However, the mechanisms linking the outcomes of ER stress in IECs to intestinal disease have not been clarified. In this study, we investigated the impact of ER stress on intestinal epithelial barrier function using human colon carcinoma-derived Caco-2 monolayers. Tunicamycin-induced ER stress decreased the trans-epithelial electrical resistance of Caco-2 monolayers, concomitant with loss of cellular plasma membrane integrity. Epithelial barrier disruption in Caco-2 cells after ER stress was not caused by caspase- or RIPK1-dependent cell death but was accompanied by lysosomal rupture and up-regulation of the ER stress markers Grp78, sXBP1 and Chop. Interestingly, several bifidobacteria species inhibited tunicamycin-induced ER stress and thereby diminished barrier disruption in Caco-2 monolayers. Together, these results showed that ER stress compromises the epithelial barrier function of Caco-2 monolayers and demonstrate beneficial impacts of bifidobacteria on ER stress in IECs. Our results identify epithelial barrier loss as a potential link between ER stress and intestinal disease development, and suggest that bifidobacteria could exert beneficial effects on this phenomenon. PMID:27611782

  6. Intestine.

    PubMed

    Smith, J M; Skeans, M A; Horslen, S P; Edwards, E B; Harper, A M; Snyder, J J; Israni, A K; Kasiske, B L

    2016-01-01

    Intestine and intestine-liver transplant plays an important role in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2014, 210 new patients were added to the intestine transplant waiting list. Among prevalent patients on the list at the end of 2014, 65% were waiting for an intestine transplant and 35% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was highest for adult candidates, at 22.1 per 100 waitlist years compared with less than 3 per 100 waitlist years for pediatric candidates, and notably higher for candidates for intestine-liver transplant than for candidates for intestine transplant without a liver. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 67 in 2014. Intestine-liver transplants increased from a low of 44 in 2012 to 72 in 2014. Short-gut syndrome (congenital and other) was the main cause of disease leading to both intestine and intestine-liver transplant. Graft survival improved over the past decade. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients. PMID:26755265

  7. Nitric oxide attenuates hydrogen peroxide-induced barrier disruption and protein tyrosine phosphorylation in monolayers of intestinal epithelial cell.

    PubMed

    Katsube, Takanori; Tsuji, Hideo; Onoda, Makoto

    2007-06-01

    The intestinal epithelium provides a barrier to the transport of harmful luminal molecules into the systemic circulation. A dysfunctional epithelial barrier is closely associated with the pathogenesis of a variety of intestinal and systemic disorders. We investigated here the effects of nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) on the barrier function of a human intestinal epithelial cell line, Caco-2. When treated with H(2)O(2), Caco-2 cell monolayers grown on permeable supports exhibited several remarkable features of barrier dysfunction as follows: a decrease in transepithelial electrical resistance, an increase in paracellular permeability to dextran, and a disruption of the intercellular junctional localization of the scaffolding protein ZO-1. In addition, an induction of tyrosine phosphorylation of numerous cellular proteins including ZO-1, E-cadherin, and beta-catenin, components of tight and adherens junctions, was observed. On the other hand, combined treatment of Caco-2 monolayers with H(2)O(2) and an NO donor (NOC5 or NOC12) relieved the damage to the barrier function and suppressed the protein tyrosine phosphorylation induced by H(2)O(2) alone. These results suggest that NO protects the barrier function of intestinal epithelia from oxidative stress by modulating some intracellular signaling pathways of protein tyrosine phosphorylation in epithelial cells. PMID:17451824

  8. Compromised intestinal epithelial barrier induces adaptive immune compensation that protects from colitis

    PubMed Central

    Khounlotham, Manirath; Kim, Wooki; Peatman, Eric; Nava, Porfirio; Medina-Contreras, Oscar; Addis, Caroline; Koch, Stefan; Fournier, Benedicte; Nusrat, Asma; Denning, Timothy L.; Parkos, Charles A.

    2012-01-01

    SUMMARY Mice lacking Junctional Adhesion Molecule A (JAM-A, encoded by F11r) exhibit enhanced intestinal epithelial permeability, bacterial translocation, and elevated colonic lymphocyte numbers, yet do not develop colitis. To investigate the contribution of adaptive immune compensation in response to increased intestinal epithelial permeability, we examined the susceptibility of F11r-/-Rag1-/- mice to acute colitis. Although negligible contributions of adaptive immunity in F11r-/-Rag1-/- mice were observed, F11r-/-Rag1-/- mice exhibited increased microflora-dependent colitis. Elimination of T cell subsets and cytokine analyses revealed a protective role for TGF-β-producing CD4+ T cells in F11r-/- mice. Additionally, loss of JAM-A resulted in elevated mucosal and serum IgA that was dependent upon CD4+ T cells and TGF-β. Absence of IgA in F11r+/+Igha-/- mice did not affect disease whereas F11r-/-Igha-/- mice displayed markedly increased susceptibility to acute injury induced colitis. These data establish a role for adaptive immune mediated protection from acute colitis under conditions of intestinal epithelial barrier compromise. PMID:22981539

  9. Low Dosage of Chitosan Supplementation Improves Intestinal Permeability and Impairs Barrier Function in Mice.

    PubMed

    Guan, Guiping; Wang, Hongbing; Peng, Hanhui; Li, Guanya

    2016-01-01

    The purpose of this study was to explore relationships between low dose dietary supplementation with chitosan (COS) and body weight, feed intake, intestinal barrier function, and permeability in mice. Twenty mice were randomly assigned to receive an unadulterated control diet (control group) or a dietary supplementation with 30 mg/kg dose of chitosan (COS group) for two weeks. Whilst no significant differences were found between the conditions for body weight or food and water intake, mice in the COS group had an increased serum D-lactate content (P < 0.05) and a decreased jejunal diamine oxidase (DAO) activity (P < 0.05). Furthermore, mice in COS group displayed a reduced expression of occludin and ZO-1 (P < 0.05) and a reduced expression of occludin in the ileum (P < 0.05). The conclusion drawn from these findings showed that although 30 mg/kg COS-supplemented diet had no effect on body weight or feed intake in mice, this dosage may compromise intestinal barrier function and permeability. This research will contribute to the guidance on COS supplements. PMID:27610376

  10. Probiotic-derived polyphosphate improves the intestinal barrier function through the caveolin-dependent endocytic pathway.

    PubMed

    Tanaka, Kazuyuki; Fujiya, Mikihiro; Konishi, Hiroaki; Ueno, Nobuhiro; Kashima, Shin; Sasajima, Junpei; Moriichi, Kentaro; Ikuta, Katsuya; Tanabe, Hiroki; Kohgo, Yutaka

    2015-11-20

    Probiotics exhibit beneficial functions for host homeostasis maintenance. We herein investigated the mechanism by which Lactobacillus brevis-derived poly P exhibited a beneficial function. Immunostaining indicated that poly P was captured in the plasma membrane via integrin β1 in Caco2/bbe cells. The uptake of poly P was reduced by the inhibition of integrin β1 as well as caveolin-1, a major component of lipid rafts. The function of poly P, including the induction of HSP27 and enhancement of the intestinal barrier function, was suppressed by the inhibition of caveolin-1, illustrating that the function of poly P was mediated by the endocytic pathway. High-throughput sequencing revealed that poly P induced tumor necrosis factor alpha-induced protein 3, which contributes to cytoprotection, including upregulation of the intestinal barrier function. The present study demonstrates a novel host-probiotic interaction through the uptake of bacterial substance into host cells, which is distinct from pattern recognition receptor pathways. PMID:26459590

  11. Low Dosage of Chitosan Supplementation Improves Intestinal Permeability and Impairs Barrier Function in Mice

    PubMed Central

    Peng, Hanhui; Li, Guanya

    2016-01-01

    The purpose of this study was to explore relationships between low dose dietary supplementation with chitosan (COS) and body weight, feed intake, intestinal barrier function, and permeability in mice. Twenty mice were randomly assigned to receive an unadulterated control diet (control group) or a dietary supplementation with 30 mg/kg dose of chitosan (COS group) for two weeks. Whilst no significant differences were found between the conditions for body weight or food and water intake, mice in the COS group had an increased serum D-lactate content (P < 0.05) and a decreased jejunal diamine oxidase (DAO) activity (P < 0.05). Furthermore, mice in COS group displayed a reduced expression of occludin and ZO-1 (P < 0.05) and a reduced expression of occludin in the ileum (P < 0.05). The conclusion drawn from these findings showed that although 30 mg/kg COS-supplemented diet had no effect on body weight or feed intake in mice, this dosage may compromise intestinal barrier function and permeability. This research will contribute to the guidance on COS supplements. PMID:27610376

  12. Protective effect of salvianolic acid B on NASH rat liver through restoring intestinal mucosal barrier function

    PubMed Central

    Wang, Ying-Chun; Jin, Qing-Mei; Kong, Wei-Zong; Chen, Juan

    2015-01-01

    Aim: To investigate the effect of Salvianolic acid B (Sal B) on the disease progress of NASH and change of intestinal barrier function. Methods: Sixty Sprague-Dawley (SD) rats were randomly divided into control group, model group and treated group, with the former given normal diet and the latter 2 groups rats fed high-fat diet. In treated group, rats were infused through the stomach with 1 mg/ml Sal B every day at a dose of 20 mL/kg body weight. All animals were killed at the 24th week and plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC), endotoxin (ET) and diamine oxdase (DAO) were analyzed using the blood samples. The histopathology of liver was observed by H&E staining. The expression changes of tight junction protein occludin and ZO-1 were analyzed by immunocytochemistry. Ultrastructural morphology of small intestinal tissues was investigated by transmission electron microscopy. Results: Plasma levels of ALT, AST, TG, TC, ET and DAO were significantly higher in model group than those in both control group and group treated with Sal B. In model group, vacuolated swelling of the cytoplasm with aggregates of chronic inflammatory cells was observed in the liver tissue but not in Sal B-treated group. NAFLD Activity Score in the treated group was significantly lower than that in model group. Immunohistochemical staining showed that Sal B administration recovered the expression of occludin and ZO-1, which was downregulated in the model group. Transmission electron microscopy analysis demonstrated that cell surface microvilli and major intercellular junctional complex including tight junction, gap junction and adherens junction were restored in Sal B-treated group. Conclusion: Sal B exerted protective function against high-fat diet-induced liver damage by restoring healthy barrier function of intestine in NASH rat model. PMID:26191218

  13. Enteral Nutrient Deprivation in Patients Leads to a Loss of Intestinal Epithelial Barrier Function

    PubMed Central

    Ralls, Matthew W.; Demehri, Farokh R.; Feng, Yongjia; Woods Ignatoski, Kathleen M.; Teitelbaum, Daniel H.

    2014-01-01

    Objective To investigate the effect of nutrient withdrawal on human intestinal epithelial barrier function (EBF). We hypothesized that unfed mucosa results in decreased EBF. This was tested in a series of surgical small intestinal resection specimens. Design Small bowel specifically excluding inflamed tissue, was obtained from pediatric patients (aged 2 days to 19 years) undergoing intestinal resection. EBF was assessed in Ussing chambers for transepithelial resistance (TER) and passage of FITC-Dextran (4kD). Tight junction and adherence junction proteins were imaged with immunofluorescence staining. Expression of Toll like receptors (TLR) and inflammatory cytokines were measured in loop ileostomy takedowns in a second group of patients. Results Because TER increased with patient age (p<0.01), results were stratified into infant versus teenage groups. Fed bowel had significantly greater TER versus unfed bowel (p<0.05) in both age populations. Loss of EBF was also observed by an increase in FITC-Dextran permeation in nutrient-deprived segments (p<0.05). Immunofluorescence staining showed marked declines in intensity of ZO-1, occludin, Ecadherin and Claudin-4 in unfed intestinal segments, as well as a loss of structural formation of tight junctions. Analysis of cytokine and TLR expression showed significant increases in TNF-α and TLR4 in unfed segments of bowel compared to fed segments from the same individual. Conclusion EBF declined in unfed segments of human small bowel. This work represents the first direct examination of EBF from small bowel derived from nutrient-deprived humans and may explain the increased infectious complications seen in patients not receiving enteral feeds. PMID:25704423

  14. Effects of simulated weightlessness on the intestinal mucosal barrier of rats

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Yang, Chun-min; Mao, Gao-ping; Liu, Qing-sen; Guo, Ming-zhou

    2011-07-01

    This study employed a rat tail-suspension model to investigate the effects of simulated weightlessness on the intestinal mucosal barrier. Twenty-four Wistar rats were randomly divided into control (CON), 14-day tail-suspension (SUS-14d), and 21-day tail-suspension (SUS-21d) groups ( n = 8 per group). Expression of occludin and zonula occludins-1 (ZO-1), proteins of the tight junction (TJ), in the intestinal mucosa was measured by immunohistochemical analysis, Western blotting, and mRNA fluorescent quantitation PCR. Plasma concentrations of diamine oxidase (DAO) and D-lactate were determined using an enzymatic spectrophotometric assay. Expression of occludin and ZO-1 was reduced in the SUS-14d and SUS-21d groups as compared to the CON group, with lowest expression observed in the SUS-21d group ( P < 0.01). Examination by transmission electron microscopy (TEM) of the jejunal epithelium revealed increased intercellular space, decreased TJ and desmosome densities, and destruction of microvilli in the SUS-14d and SUS-21d groups. Plasma DAO and D-lactate concentrations in the SUS-21d group were higher than those in SUS-14d group and significantly higher than those in the CON group ( P < 0.01). In all three groups, the expression of occludin and ZO-1 was found to correlate negatively with DAO ( P < 0.01) and D-lactate ( P < 0.01) concentrations. It is concluded that simulated weightless results in down-regulation of expression of TJ proteins in the rat intestinal mucosa. Simulated weightlessness is proposed to increase intestinal permeability through damage to the TJ.

  15. Nonmuscle Myosin IIA Regulates Intestinal Epithelial Barrier in vivo and Plays a Protective Role During Experimental Colitis

    PubMed Central

    Naydenov, Nayden G.; Feygin, Alex; Wang, Dongdong; Kuemmerle, John F.; Harris, Gianni; Conti, Mary Anne; Adelstein, Robert S.; Ivanov, Andrei I.

    2016-01-01

    The actin cytoskeleton is a critical regulator of intestinal mucosal barrier permeability, and the integrity of epithelial adherens junctions (AJ) and tight junctions (TJ). Non muscle myosin II (NM II) is a key cytoskeletal motor that controls actin filament architecture and dynamics. While NM II has been implicated in the regulation of epithelial junctions in vitro, little is known about its roles in the intestinal mucosa in vivo. In this study, we generated a mouse model with an intestinal epithelial-specific knockout of NM IIA heavy chain (NM IIA cKO) and examined the structure and function of normal gut barrier, and the development of experimental colitis in these animals. Unchallenged NM IIA cKO mice showed increased intestinal permeability and altered expression/localization of several AJ/TJ proteins. They did not develop spontaneous colitis, but demonstrated signs of a low-scale mucosal inflammation manifested by prolapses, lymphoid aggregates, increased cytokine expression, and neutrophil infiltration in the gut. NM IIA cKO animals were characterized by a more severe disruption of the gut barrier and exaggerated mucosal injury during experimentally-induced colitis. Our study provides the first evidence that NM IIA plays important roles in establishing normal intestinal barrier, and protection from mucosal inflammation in vivo. PMID:27063635

  16. Mechanism of intestinal mucosal barrier dysfunction in a rat model of chronic obstructive pulmonary disease: An observational study

    PubMed Central

    Xin, Xiaofeng; Dai, Wei; Wu, Jie; Fang, Liping; Zhao, Ming; Zhang, Pengpeng; Chen, Min

    2016-01-01

    The aim of the present study was to investigate intestinal mucosal barrier dysfunction in a rat model of chronic obstructive pulmonary disease (COPD). Male Sprague Dawley rats (n=40) were evenly randomized into control and COPD groups and the COPD model was established by regulated exposure to cigarette smoke for 6 months. Histopathological changes of the lung and intestinal tissues were detected by hematoxylin and eosin staining. Expression of the tight junction proteins occludin and zona occludens-1 (ZO-1) in the intestinal tissues were analyzed by western blotting, serum diamine oxidase (DAO) activity was detected by spectrophotometry, the urinary lactulose to mannitol ratio (L/M) was evaluated by high performance liquid chromatography, and intestinal tissue secretion of tumor necrosis factor (TNF)-α, interferon (IFN)-γ and interleukin (IL)-8 were detected by ELISA. Lung histopathology revealed thinned alveolar walls, ruptured alveolar septa, enlarged and deformed alveoli, and the formation of bullae and emphysema due to alveolar fusion in the COPD group, while intestinal histopathology indicated clearly swollen intestines with darkened and gray mucosa, neutrophil infiltration of the intestinal mucosal and regional epithelial shedding. The occludin and ZO-1 expression levels were significantly lower in the COPD group compared with those in the corresponding control group (P<0.05), while the urinary L/M ratio was significantly higher (P<0.05). Furthermore, the serum DAO activity and secretion of TNF-α, IFN-γ and IL-8 in the intestinal tissues were significantly higher in the COPD group than in the control group (each P<0.05). Dysfunctional and structural changes were observed in the intestinal mucosal barrier in COPD model rats, which may be associated with the increased intestinal inflammatory responses. PMID:27588054

  17. Protective Effects of Bifidobacterium on Intestinal Barrier Function in LPS-Induced Enterocyte Barrier Injury of Caco-2 Monolayers and in a Rat NEC Model

    PubMed Central

    Weixia, Du; Hong, Wei

    2016-01-01

    Zonulin protein is a newly discovered modulator which modulates the permeability of the intestinal epithelial barrier by disassembling intercellular tight junctions (TJ). Disruption of TJ is associated with neonatal necrotizing enterocolitis (NEC). It has been shown bifidobacterium could protect the intestinal barrier function and prophylactical administration of bifidobacterium has beneficial effects in NEC patients and animals. However, it is still unknown whether the zonulin is involved in the gut barrier dysfunction of NEC, and the protective mechanisms of bifidobacterium on intestinal barrier function are also not well understood. The present study aims to investigate the effects of bifidobacterium on intestinal barrier function, zonulin regulation, and TJ integrity both in LPS-induced enterocyte barrier injury of Caco-2 monolayers and in a rat NEC model. Our results showed bifidobacterium markedly attenuated the decrease in transepithelial electrical resistance and the increase in paracellular permeability in the Caco-2 monolayers treated with LPS (P < 0.01). Compared with the LPS group, bifidobacterium significantly decreased the production of IL-6 and TNF-α (P < 0.01) and suppressed zonulin release (P < 0.05). In addition, bifidobacterium pretreatment up-regulated occludin, claudin-3 and ZO-1 expression (P < 0.01) and also preserved these proteins localization at TJ compared with the LPS group. In the in vivo study, bifidobacterium decreased the incidence of NEC from 88 to 47% (P < 0.05) and reduced the severity in the NEC model. Increased levels of IL-6 and TNF-α in the ileum of NEC rats were normalized in bifidobacterium treated rats (P < 0.05). Moreover, administration of bifidobacterium attenuated the increase in intestinal permeability (P < 0.01), decreased the levels of serum zonulin (P < 0.05), normalized the expression and localization of TJ proteins in the ileum compared with animals with NEC. We concluded that bifidobacterium may protect against

  18. A coculture model mimicking the intestinal mucosa reveals a regulatory role for myofibroblasts in immune-mediated barrier disruption.

    PubMed

    Willemsen, L E M; Schreurs, C C H M; Kroes, H; Spillenaar Bilgen, E J; Van Deventer, S J H; Van Tol, E A F

    2002-10-01

    The pathogenesis of Crohn's disease involves a mucosal inflammatory response affecting the barrier function of the gut. Myofibroblasts directly underlining the intestinal epithelium may have a regulatory role in immune-mediated barrier disruption. A coculture system of T84 epithelial and CCD-18Co myofibroblasts was established in order to mimic the in situ spatial interactions between these cell types and to evaluate their role in barrier: integrity. Lamina propria mononuclear cells (LPMC) were introduced in co- and monocultures. Effects of immune cells on barrier integrity was determined by measuring resistance and permeability for macromolecules. Introduction of LPMC in both culture systems caused a time-dependent decrease in barrier integrity. This was found to be less pronounced in cocultures indicating a regulatory role for mesenchymal cells. The effects were also found to depend on the route of LPMC stimulation. Additional analyses suggested that the regulatory role of myofibroblasts in barrier integrity involves production of growth factors. PMID:12395905

  19. Enteral feeding and its impact on the gut immune system and intestinal mucosal barrier.

    PubMed

    Szefel, Jarosław; Kruszewski, Wiesław J; Buczek, Tomasz

    2015-01-01

    Enteral feeding is the preferred method of nutritional therapy. Mucosal lack of contact with nutrients leads do lymphoid tissue atrophy, immune system functional decline, and intensification in bacterial translocation. Currently, it is assumed that microbiome is one of the body organs that has a significant impact on health. The composition of microbiome is not affected by age, sex, or place of residence, although it changes rapidly after diet modification. The composition of the microbiome is determined by enterotype, which is specific for each organism. It has a significant impact on the risk of diabetes, cancer, atherosclerosis, and other diseases. This review gathers data on interaction between gut-associated lymphoid tissue, mucosa-associated lymphoid tissue, microbiome, and the intestinal mucosal barrier. Usually, the information on the aforementioned is scattered in specialist-subject magazines such as gastroenterology, microbiology, genetics, biochemistry, and others. PMID:26557936

  20. Microbiota and pathogen 'pas de deux': setting up and breaking down barriers to intestinal infection.

    PubMed

    McKenney, Elizabeth S; Kendall, Melissa M

    2016-07-01

    The gut microbiota plays essential roles in human health and disease. In this review, we focus on the role of the intestinal microbiota in promoting resistance to infection by bacterial pathogens as well as how pathogens overcome this barrier. We discuss how the resident microbiota restricts growth and colonization of invading pathogens by limiting availability of nutrients and through generation of a hostile environment. Additionally, we examine how microbiota-derived signaling molecules interfere with bacterial virulence. In turn, we discuss how pathogens exploit non-competitive metabolites to replicate in vivo as well as to precisely control virulence and cause disease. This bacterial two step of creating and overcoming challenges important in preventing and establishing infection highlights the complexities of elucidating interactions between the commensal bacteria and pathogens. Better understanding of microbiota-pathogen interplay will have significant implications for developing novel therapeutics to treat infectious diseases. PMID:27252177

  1. Enteral feeding and its impact on the gut immune system and intestinal mucosal barrier

    PubMed Central

    Kruszewski, Wiesław J.; Buczek, Tomasz

    2015-01-01

    Enteral feeding is the preferred method of nutritional therapy. Mucosal lack of contact with nutrients leads do lymphoid tissue atrophy, immune system functional decline, and intensification in bacterial translocation. Currently, it is assumed that microbiome is one of the body organs that has a significant impact on health. The composition of microbiome is not affected by age, sex, or place of residence, although it changes rapidly after diet modification. The composition of the microbiome is determined by enterotype, which is specific for each organism. It has a significant impact on the risk of diabetes, cancer, atherosclerosis, and other diseases. This review gathers data on interaction between gut-associated lymphoid tissue, mucosa-associated lymphoid tissue, microbiome, and the intestinal mucosal barrier. Usually, the information on the aforementioned is scattered in specialist-subject magazines such as gastroenterology, microbiology, genetics, biochemistry, and others. PMID:26557936

  2. The methionine precursor DL-2-hydroxy-(4-methylthio)butanoic acid protects intestinal epithelial barrier function.

    PubMed

    Martín-Venegas, Raquel; Brufau, M Teresa; Guerrero-Zamora, Ana Maria; Mercier, Yves; Geraert, Pierre-André; Ferrer, Ruth

    2013-12-01

    DL-2-hydroxy-(4-methylthio)butanoic acid (HMTBA) is a source of dietary methionine (Met) that is widely used in poultry nutrition. We have previously shown that HMTBA is preferentially diverted to the transsulfuration pathway, which gives antioxidant metabolites such as taurine and glutathione. Therefore, here we hypothesize that this Met source can protect epithelial barrier function in an in vitro model of intestinal inflammation of Caco-2 cells. The results show that HMTBA prevents the increase in paracellular permeability induced by H2O2 or tumour necrosis factor-α. This effect can be attributed to the increased production of taurine and reduced glutathione. Similar results were obtained for DL-Met, although the protective role of the amino acid was less pronounced than that of the hydroxy analogue. In conclusion, the diversion to the transsulfuration pathway means that this Met precursor is of greater value than previously thought, due to its capacity to improve intestinal homeostasis and the quality of poultry products destined for human consumption. PMID:23870881

  3. Intestinal and Blood-Brain Barrier Permeability of Ginkgolides and Bilobalide: In Vitro and In Vivo Approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study intestinal and blood brain barrier (BBB) transport of ginkgolides A, B, C, J and bilobalide, isolated from Ginkgo biloba (Family-Ginkgoaceae), was evaluated in Caco-2 and MDR1-MDCK cell monolayer models. Transepithelial transport was examined for 2 hours in both absorptive and secretor...

  4. CRF Induces Intestinal Epithelial Barrier Injury via the Release of Mast Cell Proteases and TNF-α

    PubMed Central

    Overman, Elizabeth L.; Rivier, Jean E.; Moeser, Adam J.

    2012-01-01

    Background and Aims Psychological stress is a predisposing factor in the onset and exacerbation of important gastrointestinal diseases including irritable bowel syndrome (IBS) and the inflammatory bowel diseases (IBD). The pathophysiology of stress-induced intestinal disturbances is known to be mediated by corticotropin releasing factor (CRF) but the precise signaling pathways remain poorly understood. Utilizing a porcine ex vivo intestinal model, the aim of this study was to investigate the mechanisms by which CRF mediates intestinal epithelial barrier disturbances. Methodology Ileum was harvested from 6–8 week-old pigs, mounted on Ussing Chambers, and exposed to CRF in the presence or absence of various pharmacologic inhibitors of CRF-mediated signaling pathways. Mucosal-to-serosal flux of 4 kDa-FITC dextran (FD4) and transepithelial electrical resistance (TER) were recorded as indices of intestinal epithelial barrier function. Results Exposure of porcine ileum to 0.05–0.5 µM CRF increased (p<0.05) paracellular flux compared with vehicle controls. CRF treatment had no deleterious effects on ileal TER. The effects of CRF on FD4 flux were inhibited with pre-treatment of tissue with the non-selective CRF1/2 receptor antagonist Astressin B and the mast cell stabilizer sodium cromolyn (10−4 M). Furthermore, anti-TNF-α neutralizing antibody (p<0.01), protease inhibitors (p<0.01) and the neural blocker tetrodotoxin (TTX) inhibited CRF-mediated intestinal barrier dysfunction. Conclusion These data demonstrate that CRF triggers increases in intestinal paracellular permeability via mast cell dependent release of TNF-α and proteases. Furthermore, CRF-mast cell signaling pathways and increases in intestinal permeability require critical input from the enteric nervous system. Therefore, blocking the deleterious effects of CRF may address the enteric signaling of mast cell degranulation, TNFα release, and protease secretion, hallmarks of IBS and IBD. PMID:22768175

  5. Probiotic-derived polyphosphate enhances the epithelial barrier function and maintains intestinal homeostasis through integrin-p38 MAPK pathway.

    PubMed

    Segawa, Shuichi; Fujiya, Mikihiro; Konishi, Hiroaki; Ueno, Nobuhiro; Kobayashi, Naoyuki; Shigyo, Tatsuro; Kohgo, Yutaka

    2011-01-01

    Probiotics exhibit beneficial effects on human health, particularly in the maintenance of intestinal homeostasis in a complex manner notwithstanding the diversity of an intestinal flora between individuals. Thus, it is highly probable that some common molecules secreted by probiotic and/or commensal bacteria contribute to the maintenance of intestinal homeostasis and protect the intestinal epithelium from injurious stimuli. To address this question, we aimed to isolate the cytoprotective compound from a lactobacillus strain, Lactobacillus brevis SBC8803 which possess the ability to induce cytoprotective heat shock proteins in mouse small intestine. L. brevis was incubated in MRS broth and the supernatant was passed through with a 0.2-µm filter. Caco2/bbe cells were treated with the culture supernatant, and HSP27 expression was evaluated by Western blotting. HSP27-inducible components were separated by ammonium sulfate precipitation, DEAE anion exchange chromatography, gel filtration, and HPLC. Finally, we identified that the HSP27-inducible fraction was polyphosphate (poly P), a simple repeated structure of phosphates, which is a common product of lactobacilli and other bacteria associated with intestinal microflora without any definitive physiological functions. Then, poly P was synthesized by poly P-synthesizing enzyme polyphosphate kinase. The synthesized poly P significantly induced HSP27 from Caco2/BBE cells. In addition, Poly P suppressed the oxidant-induced intestinal permeability in the mouse small intestine and pharmacological inhibitors of p38 MAPK and integrins counteract its protective effect. Daily intrarectal administration of poly P (10 µg) improved the inflammation grade and survival rate in 4% sodium dextran sulfate-administered mice. This study, for the first time, demonstrated that poly P is the molecule responsible for maintaining intestinal barrier actions which are mediated through the intestinal integrin β1-p38 MAPK. PMID:21858054

  6. Cellular uptake and transcytosis of lipid-based nanoparticles across the intestinal barrier: Relevance for oral drug delivery.

    PubMed

    Neves, Ana Rute; Queiroz, Joana Fontes; Costa Lima, Sofia A; Figueiredo, Francisco; Fernandes, Rui; Reis, Salette

    2016-02-01

    Oral administration is the preferred route for drug delivery and nanosystems represent a promising tool for protection and transport of hardly soluble, chemically unstable and poorly permeable drugs through the intestinal barrier. In the present work, we have studied lipid nanoparticles cellular uptake, internalization pathways and transcytosis routes through Caco-2 cell monolayers. Both lipid nanosystems presented similar size (∼180nm) and surface charge (-30mV). Nanostructured lipid carriers showed a higher cellular uptake and permeability across the barrier, but solid lipid nanoparticles could enter cells faster than the former. The internalization of lipid nanoparticles occurs mainly through a clathrin-mediated endocytosis mechanism, although caveolae-mediated endocytosis is also involved in the uptake. Both lipid nanoparticles were able to cross the intestinal barrier by a preferential transcellular route. This work contributed to a better knowledge of the developed nanosystems for the oral delivery of a wide spectrum of drugs. PMID:26550783

  7. Glial cell line-derived neurotrophic factor promotes barrier maturation and wound healing in intestinal epithelial cells in vitro.

    PubMed

    Meir, Michael; Flemming, Sven; Burkard, Natalie; Bergauer, Lisa; Metzger, Marco; Germer, Christoph-Thomas; Schlegel, Nicolas

    2015-10-15

    Recent data suggest that neurotrophic factors from the enteric nervous system are involved in intestinal epithelial barrier regulation. In this context the glial cell line-derived neurotrophic factor (GDNF) was shown to affect gut barrier properties in vivo directly or indirectly by largely undefined processes in a model of inflammatory bowel disease (IBD). We further investigated the potential role and mechanisms of GDNF in the regulation of intestinal barrier functions. Immunostaining of human gut specimen showed positive GDNF staining in enteric neuronal plexus and in enterocytes. In Western blots of the intestinal epithelial cell lines Caco2 and HT29B6, significant amounts of GDNF were detected, suggesting that enterocytes represent an additional source of GDNF. Application of recombinant GDNF on Caco2 and HT29B6 cells for 24 h resulted in significant epithelial barrier stabilization in monolayers with immature barrier functions. Wound-healing assays showed a significantly faster closure of the wounded areas after GDNF application. GDNF augmented cAMP levels and led to significant inactivation of p38 MAPK in immature cells. Activation of p38 MAPK signaling by SB-202190 mimicked GDNF-induced barrier maturation, whereas the p38 MAPK activator anisomycin blocked GDNF-induced effects. Increasing cAMP levels had adverse effects on barrier maturation, as revealed by permeability measurements. However, increased cAMP augmented the proliferation rate in Caco2 cells, and GDNF-induced proliferation of epithelial cells was abrogated by the PKA inhibitor H89. Our data show that enterocytes represent an additional source of GDNF synthesis. GDNF contributes to wound healing in a cAMP/PKA-dependent manner and promotes barrier maturation in immature enterocytes cells by inactivation of p38 MAPK signaling. PMID:26294673

  8. Glycoprotein A33 deficiency: a new mouse model of impaired intestinal epithelial barrier function and inflammatory disease

    PubMed Central

    Williams, Benjamin B.; Tebbutt, Niall C.; Buchert, Michael; Putoczki, Tracy L.; Doggett, Karen; Bao, Shisan; Johnstone, Cameron N.; Masson, Frederick; Hollande, Frederic; Burgess, Antony W.; Scott, Andrew M.; Ernst, Matthias; Heath, Joan K.

    2015-01-01

    ABSTRACT The cells of the intestinal epithelium provide a selectively permeable barrier between the external environment and internal tissues. The integrity of this barrier is maintained by tight junctions, specialised cell-cell contacts that permit the absorption of water and nutrients while excluding microbes, toxins and dietary antigens. Impairment of intestinal barrier function contributes to multiple gastrointestinal disorders, including food hypersensitivity, inflammatory bowel disease (IBD) and colitis-associated cancer (CAC). Glycoprotein A33 (GPA33) is an intestinal epithelium-specific cell surface marker and member of the CTX group of transmembrane proteins. Roles in cell-cell adhesion have been demonstrated for multiple CTX family members, suggesting a similar function for GPA33 within the gastrointestinal tract. To test a potential requirement for GPA33 in intestinal barrier function, we generated Gpa33−/− mice and subjected them to experimental regimens designed to produce food hypersensitivity, colitis and CAC. Gpa33−/− mice exhibited impaired intestinal barrier function. This was shown by elevated steady-state immunosurveillance in the colonic mucosa and leakiness to oral TRITC-labelled dextran after short-term exposure to dextran sodium sulphate (DSS) to injure the intestinal epithelium. Gpa33−/− mice also exhibited rapid onset and reduced resolution of DSS-induced colitis, and a striking increase in the number of colitis-associated tumours produced by treatment with the colon-specific mutagen azoxymethane (AOM) followed by two cycles of DSS. In contrast, Gpa33−/− mice treated with AOM alone showed no increase in sporadic tumour formation, indicating that their increased tumour susceptibility is dependent on inflammatory stimuli. Finally, Gpa33−/− mice displayed hypersensitivity to food allergens, a common co-morbidity in humans with IBD. We propose that Gpa33−/− mice provide a valuable model to study the mechanisms linking

  9. Contributions of altered permeability of intestinal barrier and defecation behavior to toxicity formation from graphene oxide in nematode Caenorhabditis elegans

    NASA Astrophysics Data System (ADS)

    Wu, Qiuli; Yin, Li; Li, Xing; Tang, Meng; Zhang, Tao; Wang, Dayong

    2013-09-01

    Graphene oxide (GO) has been extensively studied for potential biomedical applications. Meanwhile, potential GO toxicity arises in both biomedical applications and non-biomedical products where environmental exposures may occur. In the present study, we examined the potential adverse effects of GO and the underlying mechanism using nematode Caenorhabditis elegans as the assay system. We compared the in vivo effects of GO between acute exposure and prolonged exposure, and found that prolonged exposure to 0.5-100 mg L-1 of GO caused damage on functions of both primary (intestine) and secondary (neuron and reproductive organ) targeted organs. In the intestine, ROS production was significantly correlated with the formation of adverse effects on functions of both primary and secondary targeted organs. GO could be translocated into intestinal cells with loss of microvilli, and distributed to be adjacent to or surrounding mitochondria. Prolonged exposure to GO resulted in a hyper-permeable state of the intestinal barrier, an increase in mean defecation cycle length, and alteration of genes required for intestinal development and defecation behavior. Thus, our data suggest that prolonged exposure to GO may cause potential risk to environmental organisms after release into the environment. GO toxicity may be due to the combinational effects of oxidative stress in the intestinal barrier, enhanced permeability of the biological barrier, and suppressed defecation behavior in C. elegans.Graphene oxide (GO) has been extensively studied for potential biomedical applications. Meanwhile, potential GO toxicity arises in both biomedical applications and non-biomedical products where environmental exposures may occur. In the present study, we examined the potential adverse effects of GO and the underlying mechanism using nematode Caenorhabditis elegans as the assay system. We compared the in vivo effects of GO between acute exposure and prolonged exposure, and found that prolonged

  10. Protective Capacity of Resveratrol, a Natural Polyphenolic Compound, against Deoxynivalenol-Induced Intestinal Barrier Dysfunction and Bacterial Translocation.

    PubMed

    Ling, Ka-Ho; Wan, Murphy Lam Yim; El-Nezami, Hani; Wang, Mingfu

    2016-05-16

    Contamination of food/feedstuffs by mycotoxins is a serious problem worldwide, causing severe economic losses and serious health problems in animals/humans. Deoxynivalenol (DON) is a major mycotoxin contaminant and is known to impair intestinal barrier function. Grapes and red wine are rich in polyphenols, such as resveratrol (RES), which has striking antioxidant and anti-inflammatory activities. RES is a food-derived component; therefore, it may be simultaneously present with DON in the gastrointestinal tract. The aim of this study was to explore in vitro protective effects of RES against DON-induced intestinal damage. The results showed that RES could protect DON-induced bacteria translocation because of enhanced of intestinal barrier function by restoring the DON-induced decrease in transepithelial electrical resistance and increase in paracellular permeability. Further mechanistic studies demonstrated that RES protects against DON-induced barrier dysfunction by promoting the assembly of claudin-4 in the tight junction complex. This is probably mediated through modulation of IL-6 and IL-8 secretion via mitogen-activated protein kinase-dependent pathways. Our results imply that RES can protect against DON-induced intestinal damage and that RES may be used as a novel dietary intervention strategy to reduce DON toxicity in animals/humans. PMID:27058607

  11. Fermented Yupingfeng polysaccharides enhance immunity by improving the foregut microflora and intestinal barrier in weaning rex rabbits.

    PubMed

    Sun, Hao; Ni, Xueqin; Song, Xu; Wen, Bin; Zhou, Yi; Zou, Fuqin; Yang, Mingyue; Peng, Zhirong; Zhu, Hui; Zeng, Yan; Wang, Hesong; Fu, Xiangchao; Shi, Yunduo; Yin, Zhongqiong; Pan, Kangcheng; Jing, Bo; Zeng, Dong; Wang, Ping

    2016-09-01

    Yupingfeng (YPF) is a kind of Astragali radix-based ancient Chinese herbal supplemented with Atractylodis Macrocephalae Rhizoma and Radix Saposhnikoviae. Increasing evidence has proven the beneficial immunomodulating activity of YPF. However, the action mechanism(s) of it is not known. Here, we explored the immunomodulatory activity of unfermented Yupingfeng polysaccharides (UYP) and fermented Yupingfeng polysaccharides (FYP) obtained using Rhizopus oligosporus SH in weaning Rex rabbits. The results showed that both UYP and FYP exhibited notable growth-promoting and immune-enhancing activities, improvement of the intestinal flora homeostasis, and maintenance of intestinal barrier integrity and functionality. Notably, compared with UYP, FYP effectively enhanced average daily gain, organ indices, interleukin-2 (IL-2), IL-4, IL-10, tumor necrosis factor-alpha (TNF-α), TLR2, and TLR4 mRNA levels in spleen, IL-1, IL-2, IL-4, IL-6, IL-10, IL-12, TNF-α, and IFN-γ protein concentrations in serum, and TLR2 and TLR4 mRNA expressions in the gastrointestinal tract (GIT). Moreover, FYP exhibited greater beneficial effects in improving the intestinal flora, including augment flora diversity and the abundance of cellulolytic bacteria, reduction the abundance of Streptococcus spp. and Enterococcus spp. in the GIT, particularly the foregut and maintaining the intestinal barrier integrity and functionality by upregulating zonula occludens 1, claudin, polymeric immunoglobulin receptor, trefoil factor, and epidermal growth factor mRNA levels in the jejunum and ileum. Our results indicated the immunoenhancement effect of FYP is superior over that of UYP, which is probably related with the amelioration of the intestinal microflora and intestinal barrier in the foregut. PMID:27260288

  12. A new role for reticulon-4B/NOGO-B in the intestinal epithelial barrier function and inflammatory bowel disease.

    PubMed

    Rodríguez-Feo, Juan Antonio; Puerto, Marta; Fernández-Mena, Carolina; Verdejo, Cristina; Lara, José Manuel; Díaz-Sánchez, María; Álvarez, Emilio; Vaquero, Javier; Marín-Jiménez, Ignacio; Bañares, Rafael; Menchén, Luis

    2015-06-15

    Inflammatory bowel disease (IBD) is characterized by an impaired intestinal barrier function. We aimed to investigate the role of reticulon-4B (RTN-4B/NOGO-B), a structural protein of the endoplasmic reticulum, in intestinal barrier function and IBD. We used immunohistochemistry, confocal microscopy, real-time PCR, and Western blotting to study tissue distribution and expression levels of RTN-4B/NOGO-B in control and IBD samples from mouse and humans. We also targeted RTN-4B/NOGO-B using siRNAs in cultured human intestinal epithelial cell (IECs). Epithelial barrier permeability was assessed by transepithelial electrical resistance (TEER) measurement. RTN-4B/NOGO-B is expressed in the intestine mainly by IECs. Confocal microscopy revealed a colocalization of RTN-4B, E-cadherin, and polymerized actin fibers in tissue and cultured IECs. RTN-4B mRNA and protein expression were lower in the colon of IL-10(-/-) compared with wild-type mice. Colocalization of RTN-4B/E-cadherin/actin was reduced in the colon of IL-10(-/-) mice. Analysis of endoscopic biopsies from IBD patients showed a significant reduction of RTN-4B/NOGO-B expression in inflamed mucosa compared with control. Treatment of IECs with H2O2 reduced TEER values and triggered phosphorylation of RTN-4B in serine 107 residues as well as downregulation of RTN-4B expression. Acute RTN-4B/NOGO-B knockdown by siRNAs resulted in a decreased TEER values and reduction of E-cadherin and α-catenin expression and in the amount of F-actin-rich filaments in IECs. Epithelial RTN-4B/NOGO-B was downregulated in human and experimental IBD. RTN-4B participates in the intestinal epithelial barrier function, most likely via its involvement in E-cadherin, α-catenin expression, and actin cytoskeleton organization at sites of cell-to-cell contacts. PMID:25907690

  13. Apical effect of diosmectite on damage to the intestinal barrier induced by basal tumour necrosis factor-alpha.

    PubMed Central

    Mahraoui, L; Heyman, M; Plique, O; Droy-Lefaix, M T; Desjeux, J F

    1997-01-01

    BACKGROUND: In many digestive diseases the intestinal barrier is weakened by the release of proinflammatory cytokines, including tumour necrosis factor-alpha (TNF alpha). AIM: To investigate the protective effect of apical diosmectite on the intestinal dysfunction induced by the proinflammatory cytokine TNF alpha. METHODS: Filter grown monolayers of the intestinal cell line HT29-19A were incubated for 48 hours in basal medium containing 10 ng/ml TNF alpha and 5 U/ml interferon-gamma (IFN gamma). Next, 1, 10, or 100 mg/ml diosmectite was placed in the apical medium for one hour. Intestinal function was then assessed in Ussing chambers by measuring ionic conductance (G) and apicobasal fluxes of 14C-mannitol (Jman), and intact horseradish peroxidase. In control intestinal monolayers, diosmectite did not significantly modify G, Jman, or intact horseradish peroxidase. RESULTS: After incubation with TNF alpha and IFN gamma, intestinal function altered, as shown by the increases compared with control values for G (22.8 (3.7) v (9.6 (0.5) mS/cm2), Jman (33.8 (7.5) v 7.56 (0.67) micrograms/h x cm2), and intact horseradish peroxidase (1.95 (1.12) v 0.14 (0.04) micrograms/h x cm2). G and Jman were closely correlated, suggesting that the increase in permeability was paracellular. Treatment with diosmectite restored al the variables to control values. CONCLUSIONS: Basal TNF alpha disrupts the intestinal barrier through the tight junctions, and apical diosmectite counteracts this disruption. PMID:9135522

  14. Ghrelin ameliorates intestinal barrier dysfunction in experimental colitis by inhibiting the activation of nuclear factor-kappa B

    SciTech Connect

    Cheng, Jian; Zhang, Lin; Dai, Weiqi; Mao, Yuqing; Li, Sainan; Wang, Jingjie; Li, Huanqing; Guo, Chuanyong; Fan, Xiaoming

    2015-02-27

    Aim: This study aimed to investigate the effect and underlying mechanism of ghrelin on intestinal barrier dysfunction in dextran sulfate sodium (DSS)-induced colitis. Methods and results: Acute colitis was induced in C57BL/6J mice by administering 2.5% DSS. Saline or 25, 125, 250 μg/kg ghrelin was administrated intraperitoneally (IP) to mice 1 day before colitis induction and on days 4, 5, and 6 after DSS administration. IP injection of a ghrelin receptor antagonist, [D-lys{sup 3}]-GHRP-6, was performed immediately prior to ghrelin injection. Ghrelin (125 or 250 μg/kg) could reduce the disease activity index, histological score, and myeloperoxidase activities in experimental colitis, and also prevented shortening of the colon. Ghrelin could prevent the reduction of transepithelial electrical resistance and tight junction expression, and bolstered tight junction structural integrity and regulated cytokine secretion. Ultimately, ghrelin inhibited nuclear factor kappa B (NF-κB), inhibitory κB-α, myosin light chain kinase, and phosphorylated myosin light chain 2 activation. Conclusions: Ghrelin prevented the breakdown of intestinal barrier function in DSS-induced colitis. The protective effects of ghrelin on intestinal barrier function were mediated by its receptor GHSR-1a. The inhibition of NF-κB activation might be part of the mechanism underlying the effects of ghrelin that protect against barrier dysfunction. - Highlights: • Ghrelin ameliorates intestinal barrier dysfunction in experimental colitis. • The effect of ghrelin is mediated by GHSR-1a. • Inhibition of NF-κB activation.

  15. Biliary tract external drainage protects against intestinal barrier injury in hemorrhagic shock rats

    PubMed Central

    Wang, Lu; Zhao, Bing; Chen, Ying; Ma, Li; Chen, Er-Zhen; Mao, En-Qiang

    2015-01-01

    AIM: To investigate the effects of biliary tract external drainage (BTED) on intestinal barrier injury in rats with hemorrhagic shock (HS). METHODS: BTED was performed via cannula insertion into the bile duct of rats. HS was induced by drawing blood from the femoral artery at a rate of 1 mL/min until a mean arterial pressure (MAP) of 40 ± 5 mmHg was achieved. That MAP was maintained for 60 min. A total of 99 Sprague-Dawley rats were randomized into a sham group, an HS group and an HS + BTED group. Nine rats in the sham group were sacrificed 0.5 h after surgery. Nine rats in each of the HS and HS + BTED groups were sacrificed 0.5 h, 1 h, 2 h, 4 h and 6 h after resuscitation. Plasma tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and lipopolysaccharide (LPS) levels were analyzed using enzyme-linked immunosorbent assay. Plasma D-lactate levels were analyzed using colorimetry. The expression levels of occludin and claudin-1 in the ileum were analyzed using Western blot and immunohistochemistry. Histology of the ileum was evaluated by hematoxylin and eosin staining. RESULTS: Plasma TNF-α levels in the HS + BTED group decreased significantly compared with the HS group at 1 h and 6 h after resuscitation (P < 0.05). Plasma IL-6 levels in the HS + BTED group decreased significantly compared with the HS group at 0.5 h, 1 h and 2 h after resuscitation (P < 0.05). Plasma D-lactate and LPS levels in the HS + BTED group decreased significantly compared with the HS group at 6 h after resuscitation (P < 0.05). The expression levels of occludin in the HS + BTED group increased significantly compared with the HS group at 4 h and 6 h after resuscitation (P < 0.05). The expression levels of claudin-1 in the HS + BTED group increased significantly compared with the HS group at 6 h after resuscitation (P < 0.05). Phenomena of putrescence and desquamation of epithelial cells in the ileal mucosa were attenuated in the HS + BTED group. Ileal histopathologic scores in the HS

  16. Adhesions and Healing of Intestinal Anastomoses: The Effect of Anti-Adhesion Barriers.

    PubMed

    Ntourakis, Dimitrios; Katsimpoulas, Michail; Tanoglidi, Anna; Barbatis, Calypso; Karayannacos, Panayotis E; Sergentanis, Theodoros N; Kostomitsopoulos, Nikolaos; Machairas, Anastasios

    2016-06-01

    Background Postoperative adhesions are the result of aberrant peritoneal healing. As they are the leading cause of postoperative bowel obstruction, anti-adherence barriers are advocated for their prevention. This study looks into the effect of these biomaterials on the healing of intestinal anastomoses. Materials and Methods Thirty-three New Zealand White rabbits underwent laparotomy, transection of the terminal ileum, and creation of an end-to-end anastomosis. Animals were randomized into 3 groups: the Control group (n = 11); the Icodextrin group, receiving icodextrin 4% intraperitonealy (n = 11); and the HA/CMC group, having the anastomosis wrapped with a hyaluronic acid/carboxymethylcellulose film (n = 11). All animals were sacrificed on the seventh postoperative day. Macroscopic adhesions were graded and anastomotic strength was tested by the burst pressure. Histological healing was assessed in a semiquantitative way for the presence of ulceration, reepithelization, granulation tissue, inflammation, eosinophilic infiltration, serosal inflammation, and microscopic adhesions. Univariate and multivariate analysis was used. Results are given as medians with interquartile range. Results The median adhesion scores were the following: Control 1 (0-3), Icodextrin 0 (0-1), HA/CMC 0 (0-0), P = .017. The burst pressure did not differ between the groups; however, all except one bowel segments tested burst away from the anastomosis. The macroscopic and histological anastomotic healing was comparable in all 3 groups. A poor histological anastomotic healing score was associated with a higher adhesion grade (odds ratio = 1.92; 95% confidence interval = 1.06-3.47; P = .032). Conclusion Adhesion formation was inhibited by the materials tested without direct detrimental effects on anastomotic healing. Poor anastomotic healing provokes adhesions even in the presence of anti-adhesion barriers. PMID:26474604

  17. Maternal exposure to carbamazepine at environmental concentrations can cross intestinal and placental barriers.

    PubMed

    Kaushik, Gaurav; Huber, David P; Aho, Ken; Finney, Bruce; Bearden, Shawn; Zarbalis, Konstantinos S; Thomas, Michael A

    2016-05-27

    Psychoactive pharmaceuticals have been found as teratogens at clinical dosage during pregnancy. These pharmaceuticals have also been detected in minute (ppb) concentrations in drinking water in the US, and are environmental contaminants that may be complicit in triggering neurological disorders in genetically susceptible individuals. Previous studies have determined that psychoactive pharmaceuticals (fluoxetine, venlafaxine and carbamazepine) at environmentally relevant concentrations enriched sets of genes regulating development and function of the nervous system in fathead minnows. Altered gene sets were also associated with potential neurological disorders, including autism spectrum disorders (ASD). Subsequent in vitro studies indicated that psychoactive pharmaceuticals altered ASD-associated synaptic protein expression and gene expression in human neuronal cells. However, it is unknown if environmentally relevant concentrations of these pharmaceuticals are able to cross biological barriers from mother to fetus, thus potentially posing risks to nervous system development. The main objective of this study was to test whether psychoactive pharmaceuticals (fluoxetine, venlafaxine, and carbamazepine) administered through the drinking water at environmental concentrations to pregnant mice could reach the brain of the developing embryo by crossing intestinal and placental barriers. We addressed this question by adding (2)H-isotope labeled pharmaceuticals to the drinking water of female mice for 20 days (10 pre-and 10 post-conception days), and quantifying (2)H-isotope enrichment signals in the dam liver and brain of developing embryos using isotope ratio mass spectrometry. Significant levels of (2)H enrichment was detected in the brain of embryos and livers of carbamazepine-treated mice but not in those of control dams, or for fluoxetine or venlafaxine application. These results provide the first evidence that carbamazepine in drinking water and at typical

  18. Alcohol induced alterations to the human fecal VOC metabolome.

    PubMed

    Couch, Robin D; Dailey, Allyson; Zaidi, Fatima; Navarro, Karl; Forsyth, Christopher B; Mutlu, Ece; Engen, Phillip A; Keshavarzian, Ali

    2015-01-01

    Studies have shown that excessive alcohol consumption impacts the intestinal microbiota composition, causing disruption of homeostasis (dysbiosis). However, this observed change is not indicative of the dysbiotic intestinal microbiota function that could result in the production of injurious and toxic products. Thus, knowledge of the effects of alcohol on the intestinal microbiota function and their metabolites is warranted, in order to better understand the role of the intestinal microbiota in alcohol associated organ failure. Here, we report the results of a differential metabolomic analysis comparing volatile organic compounds (VOC) detected in the stool of alcoholics and non-alcoholic healthy controls. We performed the analysis with fecal samples collected after passage as well as with samples collected directly from the sigmoid lumen. Regardless of the approach to fecal collection, we found a stool VOC metabolomic signature in alcoholics that is different from healthy controls. The most notable metabolite alterations in the alcoholic samples include: (1) an elevation in the oxidative stress biomarker tetradecane; (2) a decrease in five fatty alcohols with anti-oxidant property; (3) a decrease in the short chain fatty acids propionate and isobutyrate, important in maintaining intestinal epithelial cell health and barrier integrity; (4) a decrease in alcohol consumption natural suppressant caryophyllene; (5) a decrease in natural product and hepatic steatosis attenuator camphene; and (6) decreased dimethyl disulfide and dimethyl trisulfide, microbial products of decomposition. Our results showed that intestinal microbiota function is altered in alcoholics which might promote alcohol associated pathologies. PMID:25751150

  19. Alcohol Induced Alterations to the Human Fecal VOC Metabolome

    PubMed Central

    Couch, Robin D.; Dailey, Allyson; Zaidi, Fatima; Navarro, Karl; Forsyth, Christopher B.; Mutlu, Ece; Engen, Phillip A.; Keshavarzian, Ali

    2015-01-01

    Studies have shown that excessive alcohol consumption impacts the intestinal microbiota composition, causing disruption of homeostasis (dysbiosis). However, this observed change is not indicative of the dysbiotic intestinal microbiota function that could result in the production of injurious and toxic products. Thus, knowledge of the effects of alcohol on the intestinal microbiota function and their metabolites is warranted, in order to better understand the role of the intestinal microbiota in alcohol associated organ failure. Here, we report the results of a differential metabolomic analysis comparing volatile organic compounds (VOC) detected in the stool of alcoholics and non-alcoholic healthy controls. We performed the analysis with fecal samples collected after passage as well as with samples collected directly from the sigmoid lumen. Regardless of the approach to fecal collection, we found a stool VOC metabolomic signature in alcoholics that is different from healthy controls. The most notable metabolite alterations in the alcoholic samples include: (1) an elevation in the oxidative stress biomarker tetradecane; (2) a decrease in five fatty alcohols with anti-oxidant property; (3) a decrease in the short chain fatty acids propionate and isobutyrate, important in maintaining intestinal epithelial cell health and barrier integrity; (4) a decrease in alcohol consumption natural suppressant caryophyllene; (5) a decrease in natural product and hepatic steatosis attenuator camphene; and (6) decreased dimethyl disulfide and dimethyl trisulfide, microbial products of decomposition. Our results showed that intestinal microbiota function is altered in alcoholics which might promote alcohol associated pathologies. PMID:25751150

  20. Herbal prescription Chang'an II repairs intestinal mucosal barrier in rats with post-inflammation irritable bowel syndrome

    PubMed Central

    Wang, Feng-yun; Su, Min; Zheng, Yong-qiu; Wang, Xiao-ge; Kang, Nan; Chen, Ting; Zhu, En-lin; Bian, Zhao-xiang; Tang, Xu-dong

    2015-01-01

    Aim: The herbal prescription Chang'an II is derived from a classical TCM formula Tong-Xie-Yao-Fang for the treatment of liver-qi stagnation and spleen deficiency syndrome of irritable bowel syndrome (IBS). In this study we investigated the effects of Chang'an II on the intestinal mucosal immune barrier in a rat post-inflammation IBS (PI-IBS) model. Methods: A rat model of PI-IBS was established using a multi-stimulation paradigm including early postnatal sibling deprivation, bondage and intrarectal administration of TNBS. Four weeks after TNBS administration, the rats were treated with Chang'an II (2.85, 5.71 and 11.42 g·kg−1·d−1, ig) for 14 d. Intestinal sensitivity was assessed based on the abdominal withdrawal reflex (AWR) scores and fecal water content. Open field test and two-bottle sucrose intake test were used to evaluate the behavioral changes. CD4+ and CD8+ cells were counted and IL-1β and IL-4 levels were measured in intestinal mucosa. Transmission electron microscopy was used to evaluate ultrastructural changes of the intestinal mucosal barrier. Results: PI-IBS model rats showed significantly increased AWR reactivity and fecal water content, and decreased locomotor activity and sucrose intake. Chang'an II treatment not only reduced AWR reactivity and fecal water content, but also suppressed the anxiety and depressive behaviors. Ultrastructural study revealed that the gut mucosal barrier function was severely damaged in PI-IBS model rats, whereas Chang'an II treatment relieved intestinal mucosal inflammation and repaired the gut mucosal barrier. Furthermore, PI-IBS model rats showed a significantly reduced CD4+/CD8+ cell ratio in lamina propria and submucosa, and increased IL-1β and reduced IL-4 expression in intestinal mucosa, whereas Chang'an II treatment reversed PI-IBS-induced changes in CD4+/CD8+ cell ratio and expression of IL-1β and IL-4. Conclusion: Chang'an II treatment protects the intestinal mucosa against PI-IBS through anti

  1. Serum bile acid profiling reflects enterohepatic detoxification state and intestinal barrier function in inflammatory bowel disease

    PubMed Central

    Gnewuch, Carsten; Liebisch, Gerhard; Langmann, Thomas; Dieplinger, Benjamin; Mueller, Thomas; Haltmayer, Meinhard; Dieplinger, Hans; Zahn, Alexandra; Stremmel, Wolfgang; Rogler, Gerhard; Schmitz, Gerd

    2009-01-01

    AIM: To determine free and conjugated serum bile acid (BA) levels in inflammatory bowel disease (IBD) subgroups with defined clinical manifestations. METHODS: Comprehensive serum BA profiling was performed in 358 IBD patients and 310 healthy controls by liquid chromatography coupled to electrospray ionization tandem mass spectrometry. RESULTS: Serum levels of hyodeoxycholic acid, the CYP3A4-mediated detoxification product of the secondary BA lithocholic acid (LCA), was increased significantly in Crohn’s disease (CD) and ulcerative colitis (UC), while most other serum BA species were decreased significantly. Total BA, total BA conjugate, and total BA glycoconjugate levels were decreased only in CD, whereas total unconjugated BA levels were decreased only in UC. In UC patients with hepatobiliary manifestations, the conjugated primary BAs glycocholic acid, taurocholic acid, and glycochenodeoxycholic acid were as significantly increased as the secondary BAs LCA, ursodeoxycholic acid, and tauroursodeoxycholic acid compared to UC patients without hepatobiliary manifestations. Finally, we found that in ileocecal resected CD patients, the unconjugated primary BAs, cholic acid and chenodeoxycholic acid, were increased significantly compared to controls and patients without surgical interventions. CONCLUSION: Serum BA profiling in IBD patients that indicates impaired intestinal barrier function and increased detoxification is suitable for advanced diagnostic characterization and differentiation of IBD subgroups with defined clinical manifestations. PMID:19575493

  2. Macleaya cordata Extract Decreased Diarrhea Score and Enhanced Intestinal Barrier Function in Growing Piglets

    PubMed Central

    Fang, Jun; Martínez, Yordan; Bin, Peng; Duraipandiyan, Veeramuthu; Yin, Yulong

    2016-01-01

    Macleaya cordata extract is of great scientific and practical interest to researchers, due to its antimicrobial and anti-inflammatory responses within experimental animals. This study was designed to determine the diarrhea score and innate immunity of growing piglets after they had received Macleaya cordata extract supplements. A total of 240 growing pigs were randomly assigned to one of three dietary treatments, with 8 replicates per treatment and 10 piglets per replicate. All pigs received a basal diet containing similar amounts of nutrients. The three treatments were a control (no additive), an antibiotic (200 mg/kg colistin), and the Macleaya cordata extract supplement group (40 mg/kg Macleaya cordata extract). The diarrhea score was calculated after D 28. The jejunal samples were obtained from five piglets selected randomly from each treatment on D 28. In comparison with the control group, the dietary Macleaya cordata extract and colistin group demonstrated a substantially decreased diarrhea score. The introduction of Macleaya cordata extract supplements to the diet significantly increased volumes of ZO-1 and claudin-1, particularly in comparison with the pigs in the control group (P < 0.05). The findings indicate that Macleaya cordata extract does enhance intestinal barrier function in growing piglets and that it could be used as a viable substitute for antibiotics. PMID:27525260

  3. Protective Effects of Ferulic Acid against Heat Stress-Induced Intestinal Epithelial Barrier Dysfunction In Vitro and In Vivo

    PubMed Central

    He, Shasha; Liu, Fenghua; Xu, Lei; Yin, Peng; Li, Deyin; Mei, Chen; Jiang, Linshu; Ma, Yunfei; Xu, Jianqin

    2016-01-01

    Heat stress is important in the pathogenesis of intestinal epithelial barrier dysfunction. Ferulic acid (FA), a phenolic acid widely found in fruits and vegetables, can scavenge free radicals and activate cell stress responses. This study is aimed at investigating protective effects of FA on heat stress-induced dysfunction of the intestinal epithelial barrier in vitro and in vivo. Intestinal epithelial (IEC-6) cells were pretreated with FA for 4 h and then exposed to heat stress. Heat stress caused decreased transepithelial electrical resistance (TER) and increased permeability to 4-kDa fluorescein isothiocyanate (FITC)-dextran (FD4). Both effects were inhibited by FA in a dose-dependent manner. FA significantly attenuated the decrease in occludin, ZO-1 and E-cadherin expression observed with heat stress. The distortion and redistribution of occludin, ZO-1 and E-cadherin proteins were also effectively prevented by FA pretreatment. Moreover, heat stress diminished electron-dense material detected in tight junctions (TJs), an effect also alleviated by FA in a dose-dependent manner. In an in vivo heat stress model, FA (50 mg/kg) was administered to male Sprague–Dawley rats for 7 consecutive days prior to exposure to heat stress. FA pretreatment significantly attenuated the effects of heat stress on the small intestine, including the increased FD4 permeability, disrupted tight junctions and microvilli structure, and reduced occludin, ZO-1 and E-cadherin expression. Taken together, our results demonstrate that FA pretreatment is potentially protective against heat stress-induced intestinal epithelial barrier dysfunction. PMID:26894689

  4. Protective Effects of Ferulic Acid against Heat Stress-Induced Intestinal Epithelial Barrier Dysfunction In Vitro and In Vivo.

    PubMed

    He, Shasha; Liu, Fenghua; Xu, Lei; Yin, Peng; Li, Deyin; Mei, Chen; Jiang, Linshu; Ma, Yunfei; Xu, Jianqin

    2016-01-01

    Heat stress is important in the pathogenesis of intestinal epithelial barrier dysfunction. Ferulic acid (FA), a phenolic acid widely found in fruits and vegetables, can scavenge free radicals and activate cell stress responses. This study is aimed at investigating protective effects of FA on heat stress-induced dysfunction of the intestinal epithelial barrier in vitro and in vivo. Intestinal epithelial (IEC-6) cells were pretreated with FA for 4 h and then exposed to heat stress. Heat stress caused decreased transepithelial electrical resistance (TER) and increased permeability to 4-kDa fluorescein isothiocyanate (FITC)-dextran (FD4). Both effects were inhibited by FA in a dose-dependent manner. FA significantly attenuated the decrease in occludin, ZO-1 and E-cadherin expression observed with heat stress. The distortion and redistribution of occludin, ZO-1 and E-cadherin proteins were also effectively prevented by FA pretreatment. Moreover, heat stress diminished electron-dense material detected in tight junctions (TJs), an effect also alleviated by FA in a dose-dependent manner. In an in vivo heat stress model, FA (50 mg/kg) was administered to male Sprague-Dawley rats for 7 consecutive days prior to exposure to heat stress. FA pretreatment significantly attenuated the effects of heat stress on the small intestine, including the increased FD4 permeability, disrupted tight junctions and microvilli structure, and reduced occludin, ZO-1 and E-cadherin expression. Taken together, our results demonstrate that FA pretreatment is potentially protective against heat stress-induced intestinal epithelial barrier dysfunction. PMID:26894689

  5. CKD impairs barrier function and alters microbial flora of the intestine: a major link to inflammation and uremic toxicity

    PubMed Central

    Vaziri, Nosratola D.

    2013-01-01

    Purpose of review Chronic kidney disease (CKD) is associated with oxidative stress and inflammation which contribute to progression of kidney disease and its numerous complications. Until recently, little attention had been paid to the role of the intestine and its microbial flora in the pathogenesis of CKD-associated inflammation. This article is intended to provide an over view of the impact of uremia on the structure and function of the gut and its microbial flora and their potential link to the associated systemic inflammation. Recent findings Recent studies conducted in the author’s laboratories have demonstrated marked disintegration of the colonic epithelial barrier structure and significant alteration of the colonic bacterial flora in humans and animals with advanced CKD. The observed disruption of the intestinal epithelial barrier complex can play an important part in the development of systemic inflammation by enabling influx of endotoxin and other noxious luminal contents into the systemic circulation. Similarly via disruption of the normal symbiotic relationship and production, absorption and retention of noxious products, alteration of the microbial flora can contribute to systemic inflammation and uremic toxicity. In fact recent studies have documented the role of colonic bacteria as the primary source of several well known pro-inflammatory/pro-oxidant uremic toxins as well as many as-yet unidentified retained compounds. Summary CKD results in disruption of the intestinal barrier structure and marked alteration of its microbial flora –events that play a major role in the pathogenesis of inflammation and uremic toxicity. PMID:23010760

  6. Effects of Lactobacillus johnsonii and Lactobacillus reuteri on gut barrier function and heat shock proteins in intestinal porcine epithelial cells.

    PubMed

    Liu, Hao-Yu; Roos, Stefan; Jonsson, Hans; Ahl, David; Dicksved, Johan; Lindberg, Jan Erik; Lundh, Torbjörn

    2015-04-01

    Heat shock proteins (HSPs) are a set of highly conserved proteins that can serve as intestinal gate keepers in gut homeostasis. Here, effects of a probiotic, Lactobacillus rhamnosus GG (LGG), and two novel porcine isolates, Lactobacillus johnsonii strain P47-HY and Lactobacillus reuteri strain P43-HUV, on cytoprotective HSP expression and gut barrier function, were investigated in a porcine IPEC-J2 intestinal epithelial cell line model. The IPEC-J2 cells polarized on a permeable filter exhibited villus-like cell phenotype with development of apical microvilli. Western blot analysis detected HSP expression in IPEC-J2 and revealed that L. johnsonii and L. reuteri strains were able to significantly induce HSP27, despite high basal expression in IPEC-J2, whereas LGG did not. For HSP72, only the supernatant of L. reuteri induced the expression, which was comparable to the heat shock treatment, which indicated that HSP72 expression was more stimulus specific. The protective effect of lactobacilli was further studied in IPEC-J2 under an enterotoxigenic Escherichia coli (ETEC) challenge. ETEC caused intestinal barrier destruction, as reflected by loss of cell-cell contact, reduced IPEC-J2 cell viability and transepithelial electrical resistance, and disruption of tight junction protein zonula occludens-1. In contrast, the L. reuteri treatment substantially counteracted these detrimental effects and preserved the barrier function. L. johnsonii and LGG also achieved barrier protection, partly by directly inhibiting ETEC attachment. Together, the results indicate that specific strains of Lactobacillus can enhance gut barrier function through cytoprotective HSP induction and fortify the cell protection against ETEC challenge through tight junction protein modulation and direct interaction with pathogens. PMID:25847917

  7. Effects of Lactobacillus johnsonii and Lactobacillus reuteri on gut barrier function and heat shock proteins in intestinal porcine epithelial cells

    PubMed Central

    Liu, Hao-Yu; Roos, Stefan; Jonsson, Hans; Ahl, David; Dicksved, Johan; Lindberg, Jan Erik; Lundh, Torbjörn

    2015-01-01

    Heat shock proteins (HSPs) are a set of highly conserved proteins that can serve as intestinal gate keepers in gut homeostasis. Here, effects of a probiotic, Lactobacillus rhamnosus GG (LGG), and two novel porcine isolates, Lactobacillus johnsonii strain P47-HY and Lactobacillus reuteri strain P43-HUV, on cytoprotective HSP expression and gut barrier function, were investigated in a porcine IPEC-J2 intestinal epithelial cell line model. The IPEC-J2 cells polarized on a permeable filter exhibited villus-like cell phenotype with development of apical microvilli. Western blot analysis detected HSP expression in IPEC-J2 and revealed that L. johnsonii and L. reuteri strains were able to significantly induce HSP27, despite high basal expression in IPEC-J2, whereas LGG did not. For HSP72, only the supernatant of L. reuteri induced the expression, which was comparable to the heat shock treatment, which indicated that HSP72 expression was more stimulus specific. The protective effect of lactobacilli was further studied in IPEC-J2 under an enterotoxigenic Escherichia coli (ETEC) challenge. ETEC caused intestinal barrier destruction, as reflected by loss of cell–cell contact, reduced IPEC-J2 cell viability and transepithelial electrical resistance, and disruption of tight junction protein zonula occludens-1. In contrast, the L. reuteri treatment substantially counteracted these detrimental effects and preserved the barrier function. L. johnsonii and LGG also achieved barrier protection, partly by directly inhibiting ETEC attachment. Together, the results indicate that specific strains of Lactobacillus can enhance gut barrier function through cytoprotective HSP induction and fortify the cell protection against ETEC challenge through tight junction protein modulation and direct interaction with pathogens. PMID:25847917

  8. Central role of the gut epithelial barrier in the pathogenesis of chronic intestinal inflammation: lessons learned from animal models and human genetics.

    PubMed

    Pastorelli, Luca; De Salvo, Carlo; Mercado, Joseph R; Vecchi, Maurizio; Pizarro, Theresa T

    2013-01-01

    The gut mucosa is constantly challenged by a bombardment of foreign antigens and environmental microorganisms. As such, the precise regulation of the intestinal barrier allows the maintenance of mucosal immune homeostasis and prevents the onset of uncontrolled inflammation. In support of this concept, emerging evidence points to defects in components of the epithelial barrier as etiologic factors in the pathogenesis of inflammatory bowel diseases (IBDs). In fact, the integrity of the intestinal barrier relies on different elements, including robust innate immune responses, epithelial paracellular permeability, epithelial cell integrity, as well as the production of mucus. The purpose of this review is to systematically evaluate how alterations in the aforementioned epithelial components can lead to the disruption of intestinal immune homeostasis, and subsequent inflammation. In this regard, the wealth of data from mouse models of intestinal inflammation and human genetics are pivotal in understanding pathogenic pathways, for example, that are initiated from the specific loss of function of a single protein leading to the onset of intestinal disease. On the other hand, several recently proposed therapeutic approaches to treat human IBD are targeted at enhancing different elements of gut barrier function, further supporting a primary role of the epithelium in the pathogenesis of chronic intestinal inflammation and emphasizing the importance of maintaining a healthy and effective intestinal barrier. PMID:24062746

  9. Selenium and vitamin E together improve intestinal epithelial barrier function and alleviate oxidative stress in heat-stressed pigs.

    PubMed

    Liu, Fan; Cottrell, Jeremy J; Furness, John B; Rivera, Leni R; Kelly, Fletcher W; Wijesiriwardana, Udani; Pustovit, Ruslan V; Fothergill, Linda J; Bravo, David M; Celi, Pietro; Leury, Brian J; Gabler, Nicholas K; Dunshea, Frank R

    2016-07-01

    What is the central question of this study? Oxidative stress may play a role in compromising intestinal epithelial barrier integrity in pigs subjected to heat stress, but it is unknown whether an increase of dietary antioxidants (selenium and vitamin E) could alleviate gut leakiness in heat-stressed pigs. What is the main finding and its importance? Levels of dietary selenium (1.0 p.p.m.) and vitamin E (200 IU kg(-1) ) greater than those usually recommended for pigs reduced intestinal leakiness caused by heat stress. This finding suggests that oxidative stress plays a role in compromising intestinal epithelial barrier integrity in heat-stressed pigs and also provides a nutritional strategy for mitigating these effects. Heat stress compromises the intestinal epithelial barrier integrity of mammals through mechanisms that may include oxidative stress. Our objective was to test whether dietary supplementation with antioxidants, selenium (Se) and vitamin E (VE), protects intestinal epithelial barrier integrity in heat-stressed pigs. Female growing pigs (n = 48) were randomly assigned to four diets containing from 0.2 p.p.m. Se and 17 IU kg(-1) VE (control, National Research Council recommended) to 1.0 p.p.m. Se and 200 IU kg(-1) VE for 14 days. Six pigs from each dietary treatment were then exposed to either thermoneutral (20°C) or heat-stress conditions (35°C 09.00-17.00 h and 28°C overnight) for 2 days. Transepithelial electrical resistance and fluorescein isothiocyanate-dextran (4 kDa; FD4) permeability were measured in isolated jejunum and ileum using Ussing chambers. Rectal temperature, respiratory rate and intestinal HSP70 mRNA abundance increased (all P < 0.001), and respiratory alkalosis occurred, suggesting that pigs were heat stressed. Heat stress also increased FD4 permeability and decreased transepithelial electrical resistance (both P < 0.01). These changes were associated with changes indicative of oxidative stress, a decreased

  10. Non-animal models of epithelial barriers (skin, intestine and lung) in research, industrial applications and regulatory toxicology.

    PubMed

    Gordon, Sarah; Daneshian, Mardas; Bouwstra, Joke; Caloni, Francesca; Constant, Samuel; Davies, Donna E; Dandekar, Gudrun; Guzman, Carlos A; Fabian, Eric; Haltner, Eleonore; Hartung, Thomas; Hasiwa, Nina; Hayden, Patrick; Kandarova, Helena; Khare, Sangeeta; Krug, Harald F; Kneuer, Carsten; Leist, Marcel; Lian, Guoping; Marx, Uwe; Metzger, Marco; Ott, Katharina; Prieto, Pilar; Roberts, Michael S; Roggen, Erwin L; Tralau, Tewes; van den Braak, Claudia; Walles, Heike; Lehr, Claus-Michael

    2015-01-01

    Models of the outer epithelia of the human body - namely the skin, the intestine and the lung - have found valid applications in both research and industrial settings as attractive alternatives to animal testing. A variety of approaches to model these barriers are currently employed in such fields, ranging from the utilization of ex vivo tissue to reconstructed in vitro models, and further to chip-based technologies, synthetic membrane systems and, of increasing current interest, in silico modeling approaches. An international group of experts in the field of epithelial barriers was convened from academia, industry and regulatory bodies to present both the current state of the art of non-animal models of the skin, intestinal and pulmonary barriers in their various fields of application, and to discuss research-based, industry-driven and regulatory-relevant future directions for both the development of new models and the refinement of existing test methods. Issues of model relevance and preference, validation and standardization, acceptance, and the need for simplicity versus complexity were focal themes of the discussions. The outcomes of workshop presentations and discussions, in relation to both current status and future directions in the utilization and development of epithelial barrier models, are presented by the attending experts in the current report. PMID:26536291

  11. Fish oil enhances intestinal barrier function and inhibits corticotropin-releasing hormone/corticotropin-releasing hormone receptor 1 signalling pathway in weaned pigs after lipopolysaccharide challenge.

    PubMed

    Zhu, Huiling; Liu, Yulan; Chen, Shaokui; Wang, Xiuying; Pi, Dingan; Leng, Weibo; Chen, Feng; Zhang, Jing; Kang, Ping

    2016-06-01

    Stress induces injury in intestinal barrier function in piglets. Long-chain n-3 PUFA have been shown to exhibit potential immunomodulatory and barrier protective effects in animal models and clinical trials. In addition, corticotropin-releasing hormone (CRH)/CRH receptor (CRHR) signalling pathways play an important role in stress-induced alterations of intestinal barrier function. We hypothesised that fish oil could affect intestinal barrier function and CRH/CRHR signalling pathways. In total, thirty-two weaned pigs were allocated to one of four treatments. The experiment consisted of a 2×2 factorial design, and the main factors included immunological challenge (saline or lipopolysaccharide (LPS)) and diet (5 % maize oil or 5 % fish oil). On d 19 of the trial, piglets were treated with saline or LPS. At 4 h after injection, all pigs were killed, and the mesenteric lymph nodes (MLN), liver, spleen and intestinal samples were collected. Fish oil decreased bacterial translocation incidence and the number of translocated micro-organisms in the MLN. Fish oil increased intestinal claudin-1 protein relative concentration and villus height, as well as improved the intestinal morphology. In addition, fish oil supplementation increased intestinal intraepithelial lymphocyte number and prevented elevations in intestinal mast cell and neutrophil numbers induced by LPS challenge. Moreover, fish oil tended to decrease the mRNA expression of intestinal CRHR1, CRH and glucocorticoid receptors. These results suggest that fish oil supplementation improves intestinal barrier function and inhibits CRH/CRHR1 signalling pathway and mast cell tissue density. PMID:27080003

  12. Effect of a probiotic mixture on intestinal microflora, morphology, and barrier integrity of broilers subjected to heat stress.

    PubMed

    Song, J; Xiao, K; Ke, Y L; Jiao, L F; Hu, C H; Diao, Q Y; Shi, B; Zou, X T

    2014-03-01

    The current study investigated the efficacy of a probiotic mixture on ameliorating heat stress-induced impairment of intestinal microflora, morphology, and barrier integrity in broilers. The probiotic mixture contained Bacillus licheniformis, Bacillus subtilis, and Lactobacillus plantarum. Three hundred sixty 21-d-old Ross 308 male broilers were allocated in 4 experimental treatments, each of which was replicated 6 times with 15 broilers per replicate. A 2 × 2 factorial design was used in the study, and the main factors were composed of diet (basal diet or addition of 1.5 g/kg of probiotic mixture) and temperature (thermoneutral zone or heat stress). From d 22 to 42, birds were either raised in a thermoneutral zone (22°C) or subjected to cyclic heat stress by exposing them to 33°C for 10 h (from 0800 to 1800) and 22°C from 1800 to 0800. Compared with birds kept in the thermoneutral zone, birds subjected to heat stress had reduced ADG and ADFI; lower viable counts of Lactobacillus and Bifidobacterium and increased viable counts of coliforms and Clostridium in small intestinal contents; shorter jejunal villus height, deeper crypt depth, and lower ratio of villus height to crypt depth; decreased jejunal transepithelial electrical resistance and a higher level of jejunal paracellular permeability of fluorescein isothiocyanate dextran 4 kDa; and downregulated protein levels of occludin and zonula occludens-1 (P < 0.05). Supplemental probiotics increased (P < 0.05) small intestinal Lactobacillus and Bifidobacterium, jejunal villus height, protein level of occludin, and decreased (P < 0.05) feed to gain ratio and small intestinal coliforms. These results indicate that dietary addition of probiotic mixture was effective in partially ameliorating intestinal barrier function. But no temperature × diet interaction was observed in the present study, revealing that the supplemented probiotics had the same effect at both temperatures. PMID:24604851

  13. Cellular zinc is required for intestinal epithelial barrier maintenance via the regulation of claudin-3 and occludin expression.

    PubMed

    Miyoshi, Yuka; Tanabe, Soichi; Suzuki, Takuya

    2016-07-01

    Intracellular zinc is required for a variety of cell functions, but its precise roles in the maintenance of the intestinal tight junction (TJ) barrier remain unclear. The present study investigated the essential roles of intracellular zinc in the preservation of intestinal TJ integrity and the underlying molecular mechanisms. Depletion of intracellular zinc in both intestinal Caco-2 cells and mouse colons through the application of a cell-permeable zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) induced a disruption of the TJ barrier, as indicated by increased FITC-labeled dextran flux and decreased transepithelial electrical resistance. The TPEN-induced TJ disruption is associated with downregulation of two TJ proteins, occludin and claudin-3. Biotinylation of cell surface proteins revealed that the zinc depletion induced the proteolysis of occludin but not claudin-3. Occludin proteolysis was sensitive to the inhibition of calpain activity, and increased calpain activity was observed in the zinc-depleted cells. Although quantitative PCR analysis and promoter reporter assay have demonstrated that the zinc depletion-induced claudin-3 downregulation occurred at transcriptional levels, a site-directed mutation in the egr1 binding site in the claudin-3 promoter sequence induced loss of both the basal promoter activity and the TPEN-induced decreases. Reduced egr1 expression by a specific siRNA also inhibited claudin-3 expression and transepithelial electrical resistance maintenance in cells. This study shows that intracellular zinc has an essential role in the maintenance of the intestinal epithelial TJ barrier through regulation of occludin proteolysis and claudin-3 transcription. PMID:27151944

  14. Intestinal mucosal barrier dysfunction participates in the progress of nonalcoholic fatty liver disease.

    PubMed

    Mao, Jing-Wei; Tang, Hai-Ying; Zhao, Ting; Tan, Xiao-Yan; Bi, Jian; Wang, Bing-Yuan; Wang, Ying-De

    2015-01-01

    Intestinal mucosal barrier dysfunction is closely related to liver diseases, which implies impaired gut-liver axis may play a role in the pathogenesis of NAFLD. In our study, rats were divided into three groups: normal chow diet (NCD) group, high-fat diet (HFD) group and TNBS-induced colitis with high-fat diet (C-HFD) group. Liver tissues were obtained for histological observation and TNF-α, IL-6 mRNA determination and blood samples were collected for liver enzymes and LPS analysis. Ultrastructural changes of jejuna epithelium, SIBO and amounts of CD103(+)MHCII(+)DCs and CD4(+)CD25(+)FoxP3(+)T-regs in terms of percentage in mesenteric lymph nodes (MLN) were observed by electron microscope, bacterial cultivation and flow cytometry, respectively. The results demonstrated the pathological characteristics accorded with nonalcoholic simple fatty liver (NAFL) and NASH in HFD group by week 8 and 12, respectively. Besides, the degree of hepatic steatosis and steatohepatitis was more severe in C-HFD group compared with HFD-group at the same time point. NAFLD activity score (NAS), liver enzymes, concentration of LPS and mRNA expressions of TNF-α, IL-6 were higher significantly in C-HFD group compared with HFD and NCD group at week 4, 8 and 12, respectively. In HFD group, epithelium microvilli atrophy, disruptive tight junctions and SIBO were present, and these changes were more severe in NASH compared with NAFL. The percentage of CD103+MHCII+DCs and CD4+CD25+FoxP3+T-regs decreased significantly in NAFL and NASH compared with NCD group. Our conclusion was that gut-liver axis was impaired in NAFLD, which played crucial role in the pathogenesis of NAFLD. PMID:26097546

  15. Intestinal mucosal barrier dysfunction participates in the progress of nonalcoholic fatty liver disease

    PubMed Central

    Mao, Jing-Wei; Tang, Hai-Ying; Zhao, Ting; Tan, Xiao-Yan; Bi, Jian; Wang, Bing-Yuan; Wang, Ying-De

    2015-01-01

    Intestinal mucosal barrier dysfunction is closely related to liver diseases, which implies impaired gut-liver axis may play a role in the pathogenesis of NAFLD. In our study, rats were divided into three groups: normal chow diet (NCD) group, high-fat diet (HFD) group and TNBS-induced colitis with high-fat diet (C-HFD) group. Liver tissues were obtained for histological observation and TNF-α, IL-6 mRNA determination and blood samples were collected for liver enzymes and LPS analysis. Ultrastructural changes of jejuna epithelium, SIBO and amounts of CD103+MHCII+DCs and CD4+CD25+FoxP3+T-regs in terms of percentage in mesenteric lymph nodes (MLN) were observed by electron microscope, bacterial cultivation and flow cytometry, respectively. The results demonstrated the pathological characteristics accorded with nonalcoholic simple fatty liver (NAFL) and NASH in HFD group by week 8 and 12, respectively. Besides, the degree of hepatic steatosis and steatohepatitis was more severe in C-HFD group compared with HFD-group at the same time point. NAFLD activity score (NAS), liver enzymes, concentration of LPS and mRNA expressions of TNF-α, IL-6 were higher significantly in C-HFD group compared with HFD and NCD group at week 4, 8 and 12, respectively. In HFD group, epithelium microvilli atrophy, disruptive tight junctions and SIBO were present, and these changes were more severe in NASH compared with NAFL. The percentage of CD103+MHCII+DCs and CD4+CD25+FoxP3+T-regs decreased significantly in NAFL and NASH compared with NCD group. Our conclusion was that gut-liver axis was impaired in NAFLD, which played crucial role in the pathogenesis of NAFLD. PMID:26097546

  16. Gut barrier structure, mucosal immunity and intestinal microbiota in the pathogenesis and treatment of HIV infection.

    PubMed

    Tincati, Camilla; Douek, Daniel C; Marchetti, Giulia

    2016-01-01

    Over the past 10 years, extensive work has been carried out in the field of microbial translocation in HIV infection, ranging from studies on its clinical significance to investigations on its pathogenic features. In the present work, we review the most recent findings on this phenomenon, focusing on the predictive role of microbial translocation in HIV-related morbidity and mortality, the mechanisms by which it arises and potential therapeutic approaches. From a clinical perspective, current work has shown that markers of microbial translocation may be useful in predicting clinical events in untreated HIV infection, while conflicting data exist on their role in cART-experienced subjects, possibly due to the inclusion of extremely varied patient populations in cohort studies. Results from studies addressing the pathogenesis of microbial translocation have improved our knowledge of the damage of the gastrointestinal epithelial barrier occurring in HIV infection. However, the extent to which mucosal impairment translates directly to increased gastrointestinal permeability remains an open issue. In this respect, novel work has established a role for IL-17 and IL-22-secreting T cell populations in limiting microbial translocation and systemic T-cell activation/inflammation, thus representing a possible target of immune-therapeutic interventions shown to be promising in the animal model. Further, recent reports have not only confirmed the presence of a dysbiotic intestinal community in the course of HIV infection but have also shown that it may be linked to mucosal damage, microbial translocation and peripheral immune activation. Importantly, technical advances have also shed light on the metabolic activity of gut microbes, highlighting the need for novel therapeutic approaches to correct the function, as well as the composition, of the gastrointestinal microbiota. PMID:27073405

  17. Cholera toxin disrupts barrier function by inhibiting exocyst-mediated trafficking of host proteins to intestinal cell junctions

    PubMed Central

    Guichard, Annabel; Moreno, Beatriz Cruz; Aguilar, Berenice; van Sorge, Nina M.; Kuang, Jennifer; Kurkciyan, Adrianne A.; Wang, Zhipeng; Hang, Saiyu; Pineton de Chambrun, Guillaume P.; McCole, Declan F.; Watnick, Paula; Nizet, Victor; Bier, Ethan

    2013-01-01

    Summary Cholera toxin (CT), a virulence factor elaborated by Vibrio cholerae, is sufficient to induce the severe diarrhea characteristic of cholera. The enzymatic moiety of CT (CtxA) increases cAMP synthesis in intestinal epithelial cells, leading to chloride ion (Cl−) efflux through the CFTR Cl− channel. To preserve electroneutrality and osmotic balance, sodium ions and water also flow into the intestinal lumen via a paracellular route. We find that CtxA-driven cAMP increase also inhibits Rab11/exocyst-mediated trafficking of host proteins including E-cadherin and Notch signaling components to cell-cell junctions in Drosophila, human intestinal epithelial cells, and ligated mouse ileal loops, thereby disrupting barrier function. Additionally, CtxA induces junctional damage, weight loss, and dye leakage in the Drosophila gut, contributing to lethality from live V. cholerae infection, all of which can be rescued by Rab11 over-expression. These barrier-disrupting effects of CtxA may act in parallel with Cl− secretion to drive the pathophysiology of cholera. PMID:24034615

  18. Intestinal Epithelial Barrier Disruption through Altered Mucosal MicroRNA Expression in Human Immunodeficiency Virus and Simian Immunodeficiency Virus Infections

    PubMed Central

    Gaulke, Christopher A.; Porter, Matthew; Han, Yan-Hong; Sankaran-Walters, Sumathi; Grishina, Irina; George, Michael D.; Dang, Angeline T.; Ding, Shou-Wei; Jiang, Guochun; Korf, Ian

    2014-01-01

    ABSTRACT Epithelial barrier dysfunction during human immunodeficiency virus (HIV) infection has largely been attributed to the rapid and severe depletion of CD4+ T cells in the gastrointestinal (GI) tract. Although it is known that changes in mucosal gene expression contribute to intestinal enteropathy, the role of small noncoding RNAs, specifically microRNA (miRNA), has not been investigated. Using the simian immunodeficiency virus (SIV)-infected nonhuman primate model of HIV pathogenesis, we investigated the effect of viral infection on miRNA expression in intestinal mucosa. SIV infection led to a striking decrease in the expression of mucosal miRNA compared to that in uninfected controls. This decrease coincided with an increase in 5′-3′-exoribonuclease 2 protein and alterations in DICER1 and Argonaute 2 expression. Targets of depleted miRNA belonged to molecular pathways involved in epithelial proliferation, differentiation, and immune response. Decreased expression of several miRNA involved in maintaining epithelial homeostasis in the gut was localized to the proliferative crypt region of the intestinal epithelium. Our findings suggest that SIV-induced decreased expression of miRNA involved in epithelial homeostasis, disrupted expression of miRNA biogenesis machinery, and increased expression of XRN2 are involved in the development of epithelial barrier dysfunction and gastroenteropathy. IMPORTANCE MicroRNA (miRNA) regulate the development and function of intestinal epithelial cells, and many viruses disrupt normal host miRNA expression. In this study, we demonstrate that SIV and HIV disrupt expression of miRNA in the small intestine during infection. The depletion of several key miRNA is localized to the proliferative crypt region of the gut epithelium. These miRNA are known to control expression of genes involved in inflammation, cell death, and epithelial maturation. Our data indicate that this disruption might be caused by altered expression of mi

  19. Long noncoding RNA SPRY4-IT1 regulates intestinal epithelial barrier function by modulating the expression levels of tight junction proteins

    PubMed Central

    Xiao, Lan; Rao, Jaladanki N.; Cao, Shan; Liu, Lan; Chung, Hee Kyoung; Zhang, Yun; Zhang, Jennifer; Liu, Yulan; Gorospe, Myriam; Wang, Jian-Ying

    2016-01-01

    Epithelial cells line the intestinal mucosa and form an important barrier to a wide array of noxious substances in the lumen. Disruption of the barrier integrity occurs commonly in various pathologies. Long noncoding RNAs (lncRNAs) control diverse biological processes, but little is known about the role of lncRNAs in regulation of the gut permeability. Here we show that the lncRNA SPRY4-IT1 regulates the intestinal epithelial barrier function by altering expression of tight junction (TJ) proteins. SPRY4-IT1 silencing led to dysfunction of the epithelial barrier in cultured cells by decreasing the stability of mRNAs encoding TJ proteins claudin-1, claudin-3, occludin, and JAM-1 and repressing their translation. In contrast, increasing the levels of SPRY4-IT1 in the intestinal mucosa protected the gut barrier in mice exposed to septic stress by increasing the abundance of TJ proteins. SPRY4-IT1 directly interacted with TJ mRNAs, and this process was enhanced through the association with the RNA-binding protein HuR. Of interest, the intestinal mucosa from patients with increased gut permeability exhibited a decrease in the levels of SPRY4-IT1. These findings highlight a novel role for SPRY4-IT1 in controlling the intestinal epithelial barrier and define a mechanism by which SPRY4-IT1 modulates TJ expression by altering the stability and translation of TJ mRNAs. PMID:26680741

  20. Baicalein induces CD4+Foxp3+ T cells and enhances intestinal barrier function in a mouse model of food allergy

    PubMed Central

    Bae, Min-Jung; Shin, Hee Soon; See, Hye-Jeong; Jung, Sun Young; Kwon, Da-Ae; Shon, Dong-Hwa

    2016-01-01

    The incidence of food allergy, which is triggered by allergen permeation of the gastrointestinal tract followed by a T-helper (Th) 2-mediated immune response, has been increasing annually worldwide. We examined the effects of baicalein (5,6,7-trihydroxyflavone), a flavonoid from Scutellaria baicalensis used in oriental herbal medicine, on regulatory T (Treg) cell induction and intestinal barrier function through the regulation of tight junctions in a mouse model of food allergy. An allergic response was induced by oral challenge with ovalbumin, and the incidence of allergic symptoms and T cell-related activity in the mesenteric lymph nodes were analyzed with and without the presence of baicalein. Our results demonstrated that the administration of baicalein ameliorated the symptoms of food allergy and attenuated serum IgE and effector T cells. However, Treg-related factors were up-regulated by baicalein. Furthermore, baicalein was shown to enhance intestinal barrier function through the regulation of tight junctions. We also found that baicalein treatment induced the differentiation of Treg cells via aryl hydrocarbon receptors (AhRs). Thus, the action of baicalein as an agonist of AhR can induce Treg differentiation and enhance barrier function, suggesting that baicalein might serve as an effective immune regulator derived from foods for the treatment of food allergy. PMID:27561877

  1. Baicalein induces CD4(+)Foxp3(+) T cells and enhances intestinal barrier function in a mouse model of food allergy.

    PubMed

    Bae, Min-Jung; Shin, Hee Soon; See, Hye-Jeong; Jung, Sun Young; Kwon, Da-Ae; Shon, Dong-Hwa

    2016-01-01

    The incidence of food allergy, which is triggered by allergen permeation of the gastrointestinal tract followed by a T-helper (Th) 2-mediated immune response, has been increasing annually worldwide. We examined the effects of baicalein (5,6,7-trihydroxyflavone), a flavonoid from Scutellaria baicalensis used in oriental herbal medicine, on regulatory T (Treg) cell induction and intestinal barrier function through the regulation of tight junctions in a mouse model of food allergy. An allergic response was induced by oral challenge with ovalbumin, and the incidence of allergic symptoms and T cell-related activity in the mesenteric lymph nodes were analyzed with and without the presence of baicalein. Our results demonstrated that the administration of baicalein ameliorated the symptoms of food allergy and attenuated serum IgE and effector T cells. However, Treg-related factors were up-regulated by baicalein. Furthermore, baicalein was shown to enhance intestinal barrier function through the regulation of tight junctions. We also found that baicalein treatment induced the differentiation of Treg cells via aryl hydrocarbon receptors (AhRs). Thus, the action of baicalein as an agonist of AhR can induce Treg differentiation and enhance barrier function, suggesting that baicalein might serve as an effective immune regulator derived from foods for the treatment of food allergy. PMID:27561877

  2. Optimal dietary protein level improved growth, disease resistance, intestinal immune and physical barrier function of young grass carp (Ctenopharyngodon idella).

    PubMed

    Xu, Jing; Wu, Pei; Jiang, Wei-Dan; Liu, Yang; Jiang, Jun; Kuang, Sheng-Yao; Tang, Ling; Tang, Wu-Neng; Zhang, Yong-An; Zhou, Xiao-Qiu; Feng, Lin

    2016-08-01

    This study investigated the effects of dietary proteins on the growth, disease resistance, intestinal immune and physical barrier functions of young grass carp (Ctenopharyngodon idella). A total of 540 young grass carp (264.11 ± 0.76 g) were fed six diets containing graded levels of protein (143.1, 176.7, 217.2, 257.5, 292.2 and 322.8 g digestible protein kg(-1) diet) for 8 weeks. After the growth trial, fish were challenged with Aeromonas hydrophila and mortalities were recorded for 14 days. The results indicated that optimal dietary protein levels: increased the production of antibacterial components, up-regulated anti-inflammatory cytokines, inhibitor of κBα, target of rapamycin and ribosomal protein S6 kinases 1 mRNA levels, whereas down-regulated pro-inflammatory cytokines, nuclear factor kappa B (NF-κB) P65, NF-κB P52, c-Rel, IκB kinase β, IκB kinase γ and eIF4E-binding proteins 2 mRNA levels in three intestinal segments of young grass carp (P < 0.05), suggesting that optimal dietary protein level could enhance fish intestinal immune barrier function; up-regulated the mRNA levels of tight junction complexes, B-cell lymphoma protein-2, inhibitor of apoptosis proteins, myeloid cell leukemia-1 and NF-E2-related factor 2, and increased the activities and mRNA levels of antioxidant enzymes, whereas down-regulated myosin light chain kinase, cysteinyl aspartic acid-protease 2, 3, 7, 8, 9, fatty acid synthetase ligand, apoptotic protease activating factor-1, Bcl-2 associated X protein, p38 mitogen-activated protein kinase, c-Jun N-terminal protein kinase and Kelch-like-ECH-associated protein 1b mRNA levels, and decreased reactive oxygen species, malondialdehyde and protein carbonyl contents in three intestinal segments of young grass carp (P < 0.05), indicating that optimal dietary protein level could improve fish intestinal physical barrier function. Finally, the optimal dietary protein levels for the growth performance (PWG) and against enteritis

  3. Propionate Ameliorates Dextran Sodium Sulfate-Induced Colitis by Improving Intestinal Barrier Function and Reducing Inflammation and Oxidative Stress

    PubMed Central

    Tong, Ling-chang; Wang, Yue; Wang, Zhi-bin; Liu, Wei-ye; Sun, Sheng; Li, Ling; Su, Ding-feng; Zhang, Li-chao

    2016-01-01

    Propionate is a short chain fatty acid that is abundant as butyrate in the gut and blood. However, propionate has not been studied as extensively as butyrate in the treatment of colitis. The present study was to investigate the effects of sodium propionate on intestinal barrier function, inflammation and oxidative stress in dextran sulfate sodium (DSS)-induced colitis mice. Animals in DSS group received drinking water from 1 to 6 days and DSS [3% (w/v) dissolved in double distilled water] instead of drinking water from 7 to 14 days. Animals in DSS+propionate (DSS+Prop) group were given 1% sodium propionate for 14 consecutive days and supplemented with 3% DSS solution on day 7–14. Intestinal barrier function, proinflammatory factors, oxidative stress, and signal transducer and activator of transcription 3 (STAT3) signaling pathway in the colon were determined. It was found that sodium propionate ameliorated body weight loss, colon-length shortening and colonic damage in colitis mice. Sodium propionate significantly inhibited the increase of FITC-dextran in serum and the decrease of zonula occludens-1 (ZO-1), occludin, and E-cadherin expression in the colonic tissue. It also inhibited the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) mRNA and phosphorylation of STAT3 in colitis mice markedly, reduced the myeloperoxidase (MPO) level, and increased the superoxide dismutase and catalase level in colon and serum compared with DSS group. Sodium propionate inhibited macrophages with CD68 marker infiltration into the colonic mucosa of colitis mice. These results suggest that oral administration of sodium propionate could ameliorate DSS-induced colitis mainly by improving intestinal barrier function and reducing inflammation and oxidative stress via the STAT3 signaling pathway. PMID:27574508

  4. Altered intestinal microbial flora and impaired epithelial barrier structure and function in CKD: the nature, mechanisms, consequences and potential treatment.

    PubMed

    Vaziri, Nosratola D; Zhao, Ying-Yong; Pahl, Madeleine V

    2016-05-01

    Chronic kidney disease (CKD) results in systemic inflammation and oxidative stress which play a central role in CKD progression and its adverse consequences. Although many of the causes and consequences of oxidative stress and inflammation in CKD have been extensively explored, little attention had been paid to the intestine and its microbial flora as a potential source of these problems. Our recent studies have revealed significant disruption of the colonic, ileal, jejunal and gastric epithelial tight junction in different models of CKD in rats. Moreover, the disruption of the epithelial barrier structure and function found in uremic animals was replicated in cultured human colonocytes exposed to uremic human plasma in vitro We have further found significant changes in the composition and function of colonic bacterial flora in humans and animals with advanced CKD. Together, uremia-induced impairment of the intestinal epithelial barrier structure and function and changes in composition of the gut microbiome contribute to the systemic inflammation and uremic toxicity by accommodating the translocation of endotoxin, microbial fragments and other noxious luminal products in the circulation. In addition, colonic bacteria are the main source of several well-known pro-inflammatory uremic toxins such as indoxyl sulfate, p-cresol sulfate, trimethylamine-N-oxide and many as-yet unidentified retained compounds in end-stage renal disease patients. This review is intended to provide an overview of the effects of CKD on the gut microbiome and intestinal epithelial barrier structure and their role in the pathogenesis of systemic inflammation and uremic toxicity. In addition, potential interventions aimed at mitigating these abnormalities are briefly discussed. PMID:25883197

  5. Propionate Ameliorates Dextran Sodium Sulfate-Induced Colitis by Improving Intestinal Barrier Function and Reducing Inflammation and Oxidative Stress.

    PubMed

    Tong, Ling-Chang; Wang, Yue; Wang, Zhi-Bin; Liu, Wei-Ye; Sun, Sheng; Li, Ling; Su, Ding-Feng; Zhang, Li-Chao

    2016-01-01

    Propionate is a short chain fatty acid that is abundant as butyrate in the gut and blood. However, propionate has not been studied as extensively as butyrate in the treatment of colitis. The present study was to investigate the effects of sodium propionate on intestinal barrier function, inflammation and oxidative stress in dextran sulfate sodium (DSS)-induced colitis mice. Animals in DSS group received drinking water from 1 to 6 days and DSS [3% (w/v) dissolved in double distilled water] instead of drinking water from 7 to 14 days. Animals in DSS+propionate (DSS+Prop) group were given 1% sodium propionate for 14 consecutive days and supplemented with 3% DSS solution on day 7-14. Intestinal barrier function, proinflammatory factors, oxidative stress, and signal transducer and activator of transcription 3 (STAT3) signaling pathway in the colon were determined. It was found that sodium propionate ameliorated body weight loss, colon-length shortening and colonic damage in colitis mice. Sodium propionate significantly inhibited the increase of FITC-dextran in serum and the decrease of zonula occludens-1 (ZO-1), occludin, and E-cadherin expression in the colonic tissue. It also inhibited the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) mRNA and phosphorylation of STAT3 in colitis mice markedly, reduced the myeloperoxidase (MPO) level, and increased the superoxide dismutase and catalase level in colon and serum compared with DSS group. Sodium propionate inhibited macrophages with CD68 marker infiltration into the colonic mucosa of colitis mice. These results suggest that oral administration of sodium propionate could ameliorate DSS-induced colitis mainly by improving intestinal barrier function and reducing inflammation and oxidative stress via the STAT3 signaling pathway. PMID:27574508

  6. Zinc oxide influences mitogen-activated protein kinase and TGF-β1 signaling pathways, and enhances intestinal barrier integrity in weaned pigs.

    PubMed

    Song, Ze He; Xiao, Kan; Ke, Ya Lu; Jiao, Le Fei; Hu, Cai Hong

    2015-05-01

    Weaning is the most significant event in the life of pigs and is always related with intestinal disruption. Although it is well known that zinc oxide (ZnO) exerts beneficial effects on the intestinal barrier, the mechanisms underlying these effects have not yet been fully elucidated. We examined whether ZnO protects the intestinal barrier via mitogen-activated protein kinases and TGF-β1 signaling pathways. Twelve barrows weaned at 21 d of age were randomly assigned to two treatments (0 verus 2200 mg Zn/kg from ZnO) for 1 wk. The results showed that supplementation with ZnO increased daily gain and feed intake, and decreased postweaning scour scores. ZnO improved intestinal morphology, as indicated by increased villus height and villus height:crypt depth ratio, and intestinal barrier function, indicated by increased transepithelial electrical resistance and decreased mucosal-to-serosal permeability to 4-ku FITC dextran. ZnO decreased the ratios of the phosphorylated to total JNK and p38 (p-JNK/JNK and p-p38/p38), while it increased the ratio of ERK (p-ERK/ERK). Supplementation with ZnO increased intestinal TGF-β1 expression. The results indicate that supplementation with ZnO activates ERK ½, and inhibits JNK and p38 signaling pathways, and increases intestinal TGF-β1 expression in weaned pigs. PMID:24917655

  7. Fecal microbiota transplantation and bacterial consortium transplantation have comparable effects on the re-establishment of mucosal barrier function in mice with intestinal dysbiosis

    PubMed Central

    Li, Ming; Liang, Pin; Li, Zhenzhen; Wang, Ying; Zhang, Guobin; Gao, Hongwei; Wen, Shu; Tang, Li

    2015-01-01

    Fecal microbiota transplantation (FMT) is a promising therapy, despite some reports of adverse side effects. Bacterial consortia transplantation (BCT) for targeted restoration of the intestinal ecosystem is considered a relatively safe and simple procedure. However, no systematic research has assessed the effects of FMT and BCT on immune responses of intestinal mucosal barrier in patients. We conducted complementary studies in animal models on the effects of FMT and BCT, and provide recommendations for improving the clinical outcomes of these treatments. To establish the dysbiosis model, male BALB/c mice were treated with ceftriaxone intra-gastrically for 7 days. After that, FMT and BCT were performed on ceftriaxone-treated mice for 3 consecutive days to rebuild the intestinal ecosystem. Post-FMT and post-BCT changes of the intestinal microbial community and mucosal barrier functions were investigated and compared. Disruption of intestinal microbial homeostasis impacted the integrity of mucosal epithelial layer, resulting in increased intestinal permeability. These outcomes were accompanied by overexpression of Muc2, significant decrease of SIgA secretion, and overproduction of defensins and inflammatory cytokines. After FMT and BCT, the intestinal microbiota recovered quickly, this was associated with better reconstruction of mucosal barriers and re-establishment of immune networks compared with spontaneous recovery (SR). Although based on a short-term study, our results suggest that FMT and BCT promote the re-establishment of intestinal microbial communities in mice with antibiotic-induced dysbiosis, and contribute to the temporal and spatial interactions between microbiota and mucosal barriers. The effects of BCT are comparable to that of FMT, especially in normalizing the intestinal levels of Muc2, SIgA, and defensins. PMID:26217323

  8. Protective effects of Lactobacillus plantarum on epithelial barrier disruption caused by enterotoxigenic Escherichia coli in intestinal porcine epithelial cells.

    PubMed

    Wu, Yunpeng; Zhu, Cui; Chen, Zhuang; Chen, Zhongjian; Zhang, Weina; Ma, Xianyong; Wang, Li; Yang, Xuefen; Jiang, Zongyong

    2016-04-01

    Tight junctions (TJs) play an important role in maintaining the mucosal barrier function and gastrointestinal health of animals. Lactobacillus plantarum (L. plantarum) was reported to protect the intestinal barrier function of early-weaned piglets against enterotoxigenic Escherichia coli (ETEC) K88 challenge; however, the underlying cellular mechanism of this protection was unclear. Here, an established intestinal porcine epithelia cell (IPEC-J2) model was used to investigate the protective effects and related mechanisms of L. plantarum on epithelial barrier damages induced by ETEC K88. Epithelial permeability, expression of inflammatory cytokines, and abundance of TJ proteins, were determined. Pre-treatment with L. plantarum for 6h prevented the reduction in transepithelial electrical resistance (TEER) (P<0.05), inhibited the increased transcript abundances of interleukin-8 (IL-8) and tumor necrosis factor (TNF-α) (P<0.05), decreased expression of claudin-1, occludin and zonula occludens (ZO-1) (P<0.05) and protein expression of occludin (P<0.05) of IPEC-J2 cells caused by ETEC K88. Moreover, the mRNA expression of negative regulators of toll-like receptors (TLRs) [single Ig Il-1-related receptor (SIGIRR), B-cell CLL/lymphoma 3 (Bcl3), and mitogen-activated protein kinase phosphatase-1 (MKP-1)] in IPEC-J2 cells pre-treated with L. plantarum were higher (P<0.05) compared with those in cells just exposed to K88. Furthermore, L. plantarum was shown to regulate proteins of nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. These results indicated that L. plantarum may improve epithelial barrier function by maintenance of TEER, inhibiting the reduction of TJ proteins, and reducing the expression of proinflammatory cytokines induced by ETEC K88, possibly through modulation of TLRs, NF-κB and MAPK pathways. PMID:27032504

  9. Dietary spray-dried chicken plasma improves intestinal barrier function and modulates immune status in weaning piglets.

    PubMed

    Zhang, Y; Zheng, P; Yu, B; He, J; Yu, J; Mao, X B; Wang, J X; Luo, J Q; Huang, Z Q; Cheng, G X; Chen, D W

    2016-01-01

    The objective of this study was to evaluate the effects of dietary addition of spray-dried chicken plasma (SDCP) as a replacement for spray-dried porcine plasma (SDPP) on serum biochemistry, intestinal barrier function, immune parameters, and the expression of intestinal development-related genes in weaning pigs. One hundred and forty-four 25-d-old weaning piglets with BW of 6.43 ± 0.39 kg were randomly allotted to 1 of 4 dietary treatments: 1) CON (basal diet; control), 2) SDPP (containing 5% SDPP), 3) SDPP + SDCP (containing 2.5% SDPP and 2.5% SDCP), and 4) SDCP (containing 5% SDCP). After a 28-d trial, 6 pigs from each treatment were randomly selected to collect serum and intestinal samples. On d 14 after the initiation of the trial, pigs in the SDPP, SDPP + SDCP, and SDCP groups had an increase ( < 0.05) in serum concentrations of total protein and IgG and a decrease ( < 0.05) in activities of alanine aminotransferase and diamine oxidase compared with the CON group. In the jejunum, supplementation with SDPP and SDCP reduced ( < 0.05) the concentration of tumor necrosis factor-α (TNF-α) and upregulated ( < 0.05) the mRNA levels of zonula occludens 1 (ZO-1), zonula occludens 2 (ZO-2), occludin (OCLN), Toll-like receptor 2 (TLR2), glucagon-like peptide 2 (GLP2), and IGF-1 compared with the CON group. In the ileum, feeding SDPP, SDPP + SDCP, and SDCP decreased ( < 0.05) the concentrations of TNF-α and secretory IgA (sIgA) and upregulated ( < 0.05) the mRNA levels of claudin 1 (CLDN-1) and TLR2 compared with feeding CON. However, there were no differences among the SDPP, SDPP + SDCP, and SDCP groups. Furthermore, supplementation with SDCP reduced ( < 0.05) the concentration of IL-10 and upregulated ( < 0.05) the mRNA levels of GLP-2, mucin 2 (MUC2), and trefoil factor family 3 (TFF3) in the ileum compared with feeding CON. Collectively, the current results indicate that dietary addition of SDCP has a beneficial influence on the health condition of weaning pigs

  10. Effects of Soybean Agglutinin on Mechanical Barrier Function and Tight Junction Protein Expression in Intestinal Epithelial Cells from Piglets

    PubMed Central

    Pan, Li; Qin, Guixin; Zhao, Yuan; Wang, Jun; Liu, Feifei; Che, Dongsheng

    2013-01-01

    In this study, we sought to investigate the role of soybean agglutinin (SBA) in mediating membrane permeability and the mechanical barrier function of intestinal epithelial cells. The IPEC-J2 cells were cultured and treated with 0, 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0 mg/mL SBA. Transepithelial electrical resistance (TEER) and alkaline phosphatase (AP) activity were measured to evaluate membrane permeability. The results showed a significant decrease in TEER values (p < 0.05) in a time- and dose-dependent manner, and a pronounced increase in AP activity (p < 0.05). Cell growth and cell morphology were used to evaluate the cell viability. A significant cell growth inhibition (p < 0.05) and alteration of morphology were observed when the concentration of SBA was increased. The results of western blotting showed that the expression levels of occludin and claudin-3 were decreased by 31% and 64% compared to those of the control, respectively (p < 0.05). In addition, immunofluorescence labeling indicated an obvious decrease in staining of these targets and changes in their localizations. In conclusion, SBA increased the membrane permeability, inhibited the cell viability and reduced the levels of tight junction proteins (occludin and claudin-3), leading to a decrease in mechanical barrier function in intestinal epithelial cells. PMID:24189218

  11. Prostaglandin synthesis inhibitors block alcohol-induced fetal hypoplasia.

    PubMed

    Pennington, S; Allen, Z; Runion, J; Farmer, P; Rowland, L; Kalmus, G

    1985-01-01

    Alcohol-induced growth retardation is a fetal effect consistently associated with maternal ethanol consumption. In humans, those infants whose mothers consume even a limited amount of ethanol during pregnancy have a significant incidence of growth inhibition. The molecular mechanism responsible for this growth deficiency is unknown, and prevention depends on maternal abstinence during pregnancy. The data reported here suggest that ethanol-mediated increases in tissue prostaglandin (PG) E levels (PGE1 plus PGE2) are correlated with the growth retardation. Further, simultaneous administration of PG synthesis inhibitors with the alcohol blocks the rise in tissue PG levels and protects against the alcohol-induced hypoplasia. PMID:3904508

  12. Dietary fat level and alcohol-induced pancreatic injury

    SciTech Connect

    Towner, S.J.; Inomata, T.; Largman, C.; French, S.W.

    1986-03-01

    Effects of dietary fat levels on alcohol-induced pancreatic injury were studied in a rat model which achieves sustained blood alcohol levels and maximal nutritional control. A diet containing 5, 25, or 35% of fat (corn oil; % total calories) and either ethanol or isocaloric dextrose were intragastrically infused in male Wistar rats for 30-120 days. Following intoxication, the pancreatic pathology was examined light-microscopically. None of pair-fed controls showed abnormal pancreas histology. These results indicate potentiation of alcohol-induced pancreatic injury. Particularly higher incidence of chronic interstitial pancreatitis with increased dietary fat.

  13. Effect of wild-type Shigella species and attenuated Shigella vaccine candidates on small intestinal barrier function, antigen trafficking, and cytokine release.

    PubMed

    Fiorentino, Maria; Levine, Myron M; Sztein, Marcelo B; Fasano, Alessio

    2014-01-01

    Bacterial dysentery due to Shigella species is a major cause of morbidity and mortality worldwide. The pathogenesis of Shigella is based on the bacteria's ability to invade and replicate within the colonic epithelium, resulting in severe intestinal inflammatory response and epithelial destruction. Although the mechanisms of pathogenesis of Shigella in the colon have been extensively studied, little is known on the effect of wild-type Shigella on the small intestine and the role of the host response in the development of the disease. Moreover, to the best of our knowledge no studies have described the effects of apically administered Shigella flexneri 2a and S. dysenteriae 1 vaccine strains on human small intestinal enterocytes. The aim of this study was to assess the coordinated functional and immunological human epithelial responses evoked by strains of Shigella and candidate vaccines on small intestinal enterocytes. To model the interactions of Shigella with the intestinal mucosa, we apically exposed monolayers of human intestinal Caco2 cells to increasing bacterial inocula. We monitored changes in paracellular permeability, examined the organization of tight-junctions and the pro-inflammatory response of epithelial cells. Shigella infection of Caco2 monolayers caused severe mucosal damage, apparent as a drastic increase in paracellular permeability and disruption of tight junctions at the cell-cell boundary. Secretion of pro-inflammatory IL-8 was independent of epithelial barrier dysfunction. Shigella vaccine strains elicited a pro-inflammatory response without affecting the intestinal barrier integrity. Our data show that wild-type Shigella infection causes a severe alteration of the barrier function of a small intestinal cell monolayer (a proxy for mucosa) and might contribute (along with enterotoxins) to the induction of watery diarrhea. Diarrhea may be a mechanism by which the host attempts to eliminate harmful bacteria and transport them from the small to

  14. Anemonin improves intestinal barrier restoration and influences TGF-β1 and EGFR signaling pathways in LPS-challenged piglets.

    PubMed

    Xiao, Kan; Cao, Shu Ting; Jiao, Le Fei; Lin, Fang Hui; Wang, Li; Hu, Cai Hong

    2016-07-01

    The present study was aimed at investigating whether dietary anemonin could alleviate LPS-induced intestinal injury and improve intestinal barrier restoration in a piglet model. Eighteen 35-d-old pigs were randomly assigned to three treatment groups (control, LPS and LPS+anemonin). The control and LPS groups were fed a basal diet, and the LPS + anemonin group received the basal diet + 100 mg anemonin/kg diet. After 21 d of feeding, the LPS- and anemonin-treated piglets received i.p. administration of LPS; the control group received saline. At 4 h post-injection, jejunum samples were collected. The results showed that supplemental anemonin increased villus height and transepithelial electrical resistance, and decreased crypt depth and paracellular flux of dextran (4 kDa) compared with the LPS group. Moreover, anemonin increased tight junction claudin-1, occludin and ZO-1 expression in the jejunal mucosa, compared with LPS group. Anemonin also decreased TNF-α, IL-6, IL-8 and IL-1β mRNA expression. Supplementation with anemonin also increased TGF-β1 mRNA and protein expression, Smad4 and Smad7 mRNA expressions, and epidermal growth factor and epidermal growth factor receptor (EGFR) mRNA expression in the jejunal mucosa. These findings suggest that dietary anemonin attenuates LPS-induced intestinal injury by improving mucosa restoration, alleviating intestinal inflammation and influencing TGF-β1 canonical Smads and EGFR signaling pathways. PMID:27189428

  15. Effect of Vitamin E Supplementation on Intestinal Barrier Function in Rats Exposed to High Altitude Hypoxia Environment

    PubMed Central

    Sun, Rui; Qiao, Xiangjin; Xu, Cuicui; Shang, Xiaoya; Niu, Weining; Chao, Yu

    2014-01-01

    The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia+vitamin E (250 mg/kg BW*d) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma (IFN-γ) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and IκBα, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha (HIF-1α and HIF-2α), Toll-like receptors (TLR4), P-IκBα and nuclear factor-κB p65(NF-κB P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-κB signaling pathway. PMID:25177163

  16. Randomized Clinical Trial of Pre-operative Feeding to Evaluate Intestinal Barrier Function in Neonates Requiring Cardiac Surgery

    PubMed Central

    Zyblewski, Sinai C.; Nietert, Paul J.; Graham, Eric M.; Taylor, Sarah N.; Atz, Andrew M.; Wagner, Carol L.

    2015-01-01

    Objective To evaluate intestinal barrier function in neonates undergoing cardiac surgery using lactulose/mannitol (L/M) ratio measurements and to determine correlations with early breast milk feeding. Study design This was a single-center, prospective, randomized pilot study of 27 term neonates (≥37 weeks gestation) requiring cardiac surgery who were randomized to one of two pre-operative feeding groups: 1) nil per os (NPO) vs. 2) trophic (10 cc/kg/day) breast milk feeds. At three time points (pre-op, post-op day 7, and post-op day 14), subjects were administered an oral lactulose/mannitol solution and subsequent L/M ratios were measured using gas chromatography, with higher ratios indicative of increased intestinal permeability. Trends over time in the mean urine L/M ratios for each group were estimated using a general linear mixed model. Results There were no adverse events related to pre-operative trophic feeding. In the NPO group (n=13), the mean urine L/M ratios at pre-op, post-op day 7, and post-op day 14 were 0.06, 0.12, and 0.17, respectively. In the trophic breast milk feeds group (n=14), the mean urine L/M ratios at pre-op, post-op day 7, and post-op day 14 were 0.09, 0.19, and 0.15, respectively. Both groups had significantly higher L/M ratios at post-op day 7 and 14 compared with pre-op (p<0.05). Conclusions Neonates have increased intestinal permeability after cardiac surgery extending to at least post-op day 14. This pilot study was not powered to detect differences in benefit or adverse events comparing NPO with breast milk feeds. Further studies to identify mechanisms of intestinal injury and therapeutic interventions are warranted. Trial registration Registered with ClinicalTrials.gov: NCT01475357. PMID:25962930

  17. Protective Effect of Huoxiang Zhengqi Oral Liquid on Intestinal Mucosal Mechanical Barrier of Rats with Postinfectious Irritable Bowel Syndrome Induced by Acetic Acid

    PubMed Central

    Liu, Yao; Liu, Wei; Peng, Qiu-Xian; Peng, Jiang-Li; Yu, Lin-Zhong; Hu, Jian-Lan

    2014-01-01

    In this study, a rat model with acetic acid-induced PI-IBS was used to study the role of HXZQ oral liquid in repairing the colonic epithelial barrier and reducing intestinal permeability. Pathomorphism of colonic tissue, epithelial ultrastructure, DAO activity in serum, and the protein expression of ZO-1 and occludin were examined to investigate protective effect mechanisms of HXZQ on intestinal mucosa barrier and then present experimental support for its use for prevention and cure of PI-IBS. PMID:25254052

  18. Protective effect of 1,25-dihydroxyvitamin D3 on ethanol-induced intestinal barrier injury both in vitro and in vivo.

    PubMed

    Chen, Shan-Wen; Ma, Yuan-Yuan; Zhu, Jing; Zuo, Shuai; Zhang, Jun-Ling; Chen, Zi-Yi; Chen, Guo-Wei; Wang, Xin; Pan, Yi-Sheng; Liu, Yu-Cun; Wang, Peng-Yuan

    2015-09-01

    Studies have suggested the role of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in protecting intestinal barrier function from injuries induced by multiple reagents. Vitamin D deficiency was reported to be associated with poor prognosis in patients with alcoholic liver disease (ALD). This study is designed to investigate the effect of 1,25(OH)2D3 on ethanol-induced intestinal barrier dysfunction and the underlying mechanisms utilizing Caco-2 cell monolayers and a mouse model with acute ethanol injury. In Caco-2 monolayers, ethanol significantly increased monolayer permeability, disrupted TJ distribution, increased phosphorylation level of MLC, and induced generation of ROS compared with controls. However, pre-treatment with 1,25(OH)2D3 greatly ameliorated the ethanol-induced barrier dysfunction, TJ disruption, phosphorylation level of MLC, and generation of ROS compared with ethanol-exposed monolayers. Mice fed with vitamin d-sufficient diet had a higher plasma level of 25(OH)D3 and were more resistant to ethanol-induced acute intestinal barrier injury compared with the vitamin d-deficient group. These results suggest that the suppression of generation of ROS and increased phosphorylation level of MLC might be one of the mechanisms underlying the protective effect of 1,25(OH)2D3 on ethanol-induced intestinal barrier injury and provide evidence for the application of vitamin D as therapeutic factors against ethanol-induced gut leakiness. PMID:26068064

  19. Alcohol-Induced Myocardial Fibrosis in Metallothionein-Null Mice

    PubMed Central

    Wang, Lipeng; Zhou, Zhanxiang; Saari, Jack T.; Kang, Y. James

    2005-01-01

    Alcohol-induced cardiomyopathy including fibrosis has been recognized clinically for a long time, but its pathogenesis is incompletely understood. Studies using experimental animals have not fully duplicated the pathological changes in humans, and animal models of alcoholic cardiac fibrosis are not available. In the present study, we have developed a mouse model in which cardiac hypertrophy and fibrosis were produced in metallothionein-knockout (MT-KO) mice fed an alcohol-containing liquid diet for 2 months. The same alcohol feeding did not produce cardiac fibrosis in the wild-type (WT) control mice, although there was no difference in the alcohol-induced heart hypertrophy between the WT controls and the MT-KO mice. Zinc supplementation prevented cardiac fibrosis but did not affect heart hypertrophy in the alcohol-fed MT-KO mice, suggesting a specific link between zinc homeostasis and cardiac fibrosis. Serum creatine phosphokinase activity was significantly higher in the alcohol-administered MT-KO mice than in the WT mice, and zinc supplementation decreased serum creatine phosphokinase activities and eliminated the difference between the groups. Thus, disturbance in zinc homeostasis due to the lack of MT associates with alcohol-induced cardiac fibrosis and more severe cardiac injury, making the MT-KO mouse model of alcohol-induced cardiac fibrosis a useful tool to investigate specific factors involved in the alcoholic cardiomyopathy. PMID:16049321

  20. Intestinal Barrier Dysfunction Develops at the Onset of Experimental Autoimmune Encephalomyelitis, and Can Be Induced by Adoptive Transfer of Auto-Reactive T Cells

    PubMed Central

    Nouri, Mehrnaz; Bredberg, Anders; Weström, Björn; Lavasani, Shahram

    2014-01-01

    Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with a pathogenesis involving a dysfunctional blood-brain barrier and myelin-specific, autoreactive T cells. Although the commensal microbiota seems to affect its pathogenesis, regulation of the interactions between luminal antigens and mucosal immune elements remains unclear. Herein, we investigated whether the intestinal mucosal barrier is also targeted in this disease. Experimental autoimmune encephalomyelitis (EAE), the prototypic animal model of MS, was induced either by active immunization or by adoptive transfer of autoreactive T cells isolated from these mice. We show increased intestinal permeability, overexpression of the tight junction protein zonulin and alterations in intestinal morphology (increased crypt depth and thickness of the submucosa and muscularis layers). These intestinal manifestations were seen at 7 days (i.e., preceding the onset of neurological symptoms) and at 14 days (i.e., at the stage of paralysis) after immunization. We also demonstrate an increased infiltration of proinflammatory Th1/Th17 cells and a reduced regulatory T cell number in the gut lamina propria, Peyer's patches and mesenteric lymph nodes. Adoptive transfer to healthy mice of encephalitogenic T cells, isolated from EAE-diseased animals, led to intestinal changes similar to those resulting from the immunization procedure. Our findings show that disruption of intestinal homeostasis is an early and immune-mediated event in EAE. We propose that this intestinal dysfunction may act to support disease progression, and thus represent a potential therapeutic target in MS. In particular, an increased understanding of the regulation of tight junctions at the blood-brain barrier and in the intestinal wall may be crucial for design of future innovative therapies. PMID:25184418

  1. Production of interferon-γ by activated T-cell receptor-αβ CD8αβ intestinal intraepithelial lymphocytes is required and sufficient for disruption of the intestinal barrier integrity

    PubMed Central

    Zufferey, Christel; Erhart, Dominik; Saurer, Leslie; Mueller, Christoph

    2009-01-01

    Maintenance of intestinal epithelial barrier function is of vital importance in preventing uncontrolled influx of antigens and the potentially ensuing inflammatory disorders. Intestinal intraepithelial lymphocytes (IEL) are in intimate contact with epithelial cells and may critically regulate the epithelial barrier integrity. While a preserving impact has been ascribed to the T-cell receptor (TCR)-γδ subset of IEL, IEL have also been shown to attenuate the barrier function. The present study sought to clarify the effects of IEL by specifically investigating the influence of the TCR-αβ CD8αβ and TCR-αβ CD8αα subsets of IEL on the intestinal epithelial barrier integrity. To this end, an in vitro coculture system of the murine intestinal crypt-derived cell-line mICcl2 and syngeneic ex vivo isolated IEL was employed. Epithelial integrity was assessed by analysis of transepithelial resistance (TER) and paracellular flux of fluorescein isothiocyanate-conjugated (FITC-) dextran. The TCR-αβ CD8αα IEL and resting TCR-αβ CD8αβ IEL did not affect TER of mICcl2 or flux of FITC-dextran. In contrast, activated TCR-αβ CD8αβ IEL clearly disrupted the integrity of the mICcl2 monolayer. No disrupting effect was seen with activated TCR-αβ CD8αβ IEL from interferon-γ knockout mice. These findings demonstrate that secretion of interferon-γ by activated TCR-αβ CD8αβ IEL is strictly required and also sufficient for disrupting the intestinal epithelial barrier function. PMID:20067535

  2. Probiotics Prevent Intestinal Barrier Dysfunction in Acute Pancreatitis in Rats via Induction of Ileal Mucosal Glutathione Biosynthesis

    PubMed Central

    Lutgendorff, Femke; Nijmeijer, Rian M.; Sandström, Per A.; Trulsson, Lena M.; Magnusson, Karl-Eric; Timmerman, Harro M.; van Minnen, L. Paul; Rijkers, Ger T.; Gooszen, Hein G.; Akkermans, Louis M. A.; Söderholm, Johan D.

    2009-01-01

    Background During acute pancreatitis (AP), oxidative stress contributes to intestinal barrier failure. We studied actions of multispecies probiotics on barrier dysfunction and oxidative stress in experimental AP. Methodology/Principal Findings Fifty-three male Spraque-Dawley rats were randomly allocated into five groups: 1) controls, non-operated, 2) sham-operated, 3) AP, 4) AP and probiotics and 5) AP and placebo. AP was induced by intraductal glycodeoxycholate infusion and intravenous cerulein (6 h). Daily probiotics or placebo were administered intragastrically, starting five days prior to AP. After cerulein infusion, ileal mucosa was collected for measurements of E. coli K12 and 51Cr-EDTA passage in Ussing chambers. Tight junction proteins were investigated by confocal immunofluorescence imaging. Ileal mucosal apoptosis, lipid peroxidation, and glutathione levels were determined and glutamate-cysteine-ligase activity and expression were quantified. AP-induced barrier dysfunction was characterized by epithelial cell apoptosis and alterations of tight junction proteins (i.e. disruption of occludin and claudin-1 and up-regulation of claudin-2) and correlated with lipid peroxidation (r>0.8). Probiotic pre-treatment diminished the AP-induced increase in E. coli passage (probiotics 57.4±33.5 vs. placebo 223.7±93.7 a.u.; P<0.001), 51Cr-EDTA flux (16.7±10.1 vs. 32.1±10.0 cm/s10−6; P<0.005), apoptosis, lipid peroxidation (0.42±0.13 vs. 1.62±0.53 pmol MDA/mg protein; P<0.001), and prevented tight junction protein disruption. AP-induced decline in glutathione was not only prevented (14.33±1.47 vs. 8.82±1.30 nmol/mg protein, P<0.001), but probiotics even increased mucosal glutathione compared with sham rats (14.33±1.47 vs. 10.70±1.74 nmol/mg protein, P<0.001). Glutamate-cysteine-ligase activity, which is rate-limiting in glutathione biosynthesis, was enhanced in probiotic pre-treated animals (probiotics 2.88±1.21 vs. placebo 1.94±0.55 nmol/min/mg protein; P<0

  3. [Barrier- and autophagic functions of the intestinal epithelia: role of disturbances in the pathogenesis of Crohn's disease].

    PubMed

    Lapis, Károly

    2010-10-01

    Crohn's disease is a widely known debilitating chronic inflammatory disease, mostly affecting terminal ileum and/or colon. Epidemiological, familial and twin studies suggest that genetic factors play an important role in susceptibility to the disease. Clinical observations suggest that ill-defined environmental factors also play a part. Advances in molecular genotyping technology, statistical methodologies, bioinformatics and the combined use of them in genome wide scanning and association studies resulted in the identification of more than 30 susceptibility genes and loci associated with Crohn's disease and revealed and highlighted a number of new previously unsuspected pathways playing a role in the pathogenesis of Crohn's disease. Close association of the disease with polymorphisms in the genes encoding the pattern recognition receptors particularly the NOD2 protein, the Wnt pathway transcription factor Tcf4 (also known as TCFL2) and the autophagic regulator ATG16L1 have been found. The polymorphisms involved are associated with decreased defensin production (defensin deficiency) which can lead to changes in the composition of the commensal microbial flora, defects in the intestinal barrier functions and bacterial invasion of the mucosa. Other recently recognized consequences of the polymorphisms involving the genes encoding NOD2 and ATG16L1 proteins are that the truncated NOD2 protein is unable to induce autophagy and this protein, just like the ATG16L1 T300A mutant protein, leads to failure adequately to destroy phagocytosed bacteria. The consequence is persisting low level infection, chronic intestinal inflammation, tissue injury and the clinical symptoms of the disease. Thus, Crohn's disease can be seen to be caused by defects in the innate immune defense, in particular defects in bacterial processing and clearance. The accumulated evidence suggests that Crohn's disease is associated with an exaggerated adaptive immune response to the persisting intestinal

  4. Ste20-related proline/alanine-rich kinase (SPAK) regulated transcriptionally by hyperosmolarity is involved in intestinal barrier function.

    PubMed

    Yan, Yutao; Dalmasso, Guillaume; Nguyen, Hang Thi Thu; Obertone, Tracy S; Sitaraman, Shanthi V; Merlin, Didier

    2009-01-01

    The Ste20-related protein proline/alanine-rich kinase (SPAK) plays important roles in cellular functions such as cell differentiation and regulation of chloride transport, but its roles in pathogenesis of intestinal inflammation remain largely unknown. Here we report significantly increased SPAK expression levels in hyperosmotic environments, such as mucosal biopsy samples from patients with Crohn's disease, as well as colon tissues of C57BL/6 mice and Caco2-BBE cells treated with hyperosmotic medium. NF-kappaB and Sp1-binding sites in the SPAK TATA-less promoter are essential for SPAK mRNA transcription. Hyperosmolarity increases the ability of NF-kappaB and Sp1 to bind to their binding sites. Knock-down of either NF-kappaB or Sp1 by siRNA reduces the hyperosmolarity-induced SPAK expression levels. Furthermore, expression of NF-kappaB, but not Sp1, was upregulated by hyperosmolarity in vivo and in vitro. Nuclear run-on assays showed that hyperosmolarity increases SPAK expression levels at the transcriptional level, without affecting SPAK mRNA stability. Knockdown of SPAK expression by siRNA or overexpression of SPAK in cells and transgenic mice shows that SPAK is involved in intestinal permeability in vitro and in vivo. Together, our data suggest that SPAK, the transcription of which is regulated by hyperosmolarity, plays an important role in epithelial barrier function. PMID:19343169

  5. Effect of tannic acid-fish scale gelatin hydrolysate hybrid nanoparticles on intestinal barrier function and α-amylase activity.

    PubMed

    Wu, Shao-Jung; Ho, Yi-Cheng; Jiang, Shun-Zhou; Mi, Fwu-Long

    2015-07-01

    Practical application of tannic acid is limited because it readily binds proteins to form insoluble aggregates. In this study, tannic acid was self-assembled with fish scale gelatin hydrolysates (FSGH) to form stable colloidal complex nanoparticles. The nanoparticles prepared from 4 mg ml(-1) tannic acid and 4 mg ml(-1) FSGH had a mean particle size of 260.8 ± 3.6 nm, and showed a positive zeta potential (20.4 ± 0.4 mV). The nanoparticles acted as effective nano-biochelators and free radical scavengers because they provided a large number of adsorption sites for interaction with heavy metal ions and scavenging free radicals. The maximum adsorption capacity for Cu(2+) ions was 123.5 mg g(-1) and EC50 of DPPH radical scavenging activity was 21.6 ± 1.2 μg ml(-1). Hydroxyl radical scavenging effects of the nanoparticles were investigated by electron spin resonance spectroscopy. The copper-chelating capacity and free radical scavenging activity of the nanoparticles were associated with their capacity to inhibit Cu(2+) ion-induced barrier impairment and hyperpermeability of Caco-2 intestinal epithelial tight junction (TJ). However, α-amylase inhibitory activity of the nanoparticles was significantly lower than that of free tannic acid. The results suggest that the nanoparticles can ameliorate Cu(2+) ion induced intestinal epithelial TJ dysfunction without severely inhibiting the activity of the digestive enzymes. PMID:26069899

  6. Intestinal barrier analysis by assessment of mucins, tight junctions, and α-defensins in healthy C57BL/6J and BALB/cJ mice.

    PubMed

    Volynets, Valentina; Rings, Andreas; Bárdos, Gyöngyi; Ostaff, Maureen J; Wehkamp, Jan; Bischoff, Stephan C

    2016-01-01

    The intestinal barrier is gaining increasing attention because it is related to intestinal homeostasis and disease. Different parameters have been used in the past to assess intestinal barrier functions in experimental studies; however most of them are poorly defined in healthy mice. Here, we compared a number of barrier markers in healthy mice, established normal values and correlations. In 48 mice (24 C57BL/6J, 24 BALB/cJ background), we measured mucus thickness, and expression of mucin-2, α-defensin-1 and -4, zonula occludens-1, occludin, junctional adhesion molecule-A, claudin-1, 2 and -5. We also analyzed claudin-3 and fatty acid binding protein-2 in urine and plasma, respectively. A higher expression of mucin-2 protein was found in the colon compared to the ileum. In contrast, the α-defensins-1 and -4 were expressed almost exclusively in the ileum. The protein expression of the tight junction molecules claudin-1, occludin and zonula occludens-1 did not differ between colon and ileum, although some differences occurred at the mRNA level. No age- or gender-related differences were found. Differences between C57BL/6J and BALB/cJ mice were found for α-defensin-1 and -4 mRNA expression, and for urine and plasma marker concentrations. The α-defensin-1 mRNA correlated with claudin-5 mRNA, whereas α-defensin-4 mRNA correlated with claudin-3 concentrations in urine. In conclusion, we identified a number of murine intestinal barrier markers requiring tissue analyses or measurable in urine or plasma. We provide normal values for these markers in mice of different genetic background. Such data might be helpful for future animal studies in which the intestinal barrier is of interest. PMID:27583194

  7. Effects of phenol on barrier function of a human intestinal epithelial cell line correlate with altered tight junction protein localization.

    PubMed

    McCall, Ingrid C; Betanzos, Abigail; Weber, Dominique A; Nava, Porfirio; Miller, Gary W; Parkos, Charles A

    2009-11-15

    Phenol contamination of soil and water has raised concerns among people living near phenol-producing factories and hazardous waste sites containing the chemical. Phenol, particularly in high concentrations, is an irritating and corrosive substance, making mucosal membranes targets of toxicity in humans. However, few data on the effects of phenol after oral exposure exist. We used an in vitro model employing human intestinal epithelial cells (SK-CO15) cultured on permeable supports to examine effects of phenol on epithelial barrier function. We hypothesized that phenol disrupts epithelial barrier by altering tight junction (TJ) protein expression. The dose-response effect of phenol on epithelial barrier function was determined using transepithelial electrical resistance (TER) and FITC-dextran permeability measurements. We studied phenol-induced changes in cell morphology and expression of several tight junction proteins by immunofluorescence and Western blot analysis. Effects on cell viability were assessed by MTT, Trypan blue, propidium iodide and TUNEL staining. Exposure to phenol resulted in decreased TER and increased paracellular flux of FITC-dextran in a dose-dependent manner. Delocalization of claudin-1 and ZO-1 from TJs to cytosol correlated with the observed increase in permeability after phenol treatment. Additionally, the decrease in TER correlated with changes in the distribution of a membrane raft marker, suggesting phenol-mediated effects on membrane fluidity. Such observations were independent of effects of phenol on cell viability as enhanced permeability occurred at doses of phenol that did not cause cell death. Overall, these findings suggest that phenol may affect transiently the lipid bilayer of the cell membrane, thus destabilizing TJ-containing microdomains. PMID:19679145

  8. Effects of phenol on barrier function of a human intestinal epithelial cell line correlate with altered tight junction protein localization

    PubMed Central

    McCall, Ingrid C.; Betanzos, Abigail; Weber, Dominique A.; Nava, Porfirio; Miller, Gary W.; Parkos, Charles A.

    2010-01-01

    Phenol contamination of soil and water has raised concerns among people living near phenol-producing factories and hazardous waste sites containing the chemical. Phenol, particularly in high concentrations, is an irritating and corrosive substance, making mucosal membranes targets of toxicity in humans. However, few data on the effects of phenol after oral exposure exist. We used an in vitro model employing human intestinal epithelial cells (SK-CO15) cultured on permeable supports to examine effects of phenol on epithelial barrier function. We hypothesized that phenol disrupts epithelial barrier by altering tight junction (TJ) protein expression. The dose-response effect of phenol on epithelial barrier function was determined using transepithelial electrical resistance (TER) and FITC-dextran permeability measurements. We studied phenol-induced changes in cell morphology and expression of several tight junction proteins by immunofluorescence and Western blot analysis. Effects on cell viability were assessed by MTT, Trypan blue, propidium iodide and TUNEL staining. Exposure to phenol resulted in decreased TER and increased paracellular flux of FITC-dextran in a dose-dependent manner. Delocalization of claudin-1 and ZO-1 from TJs to cytosol correlated with the observed increase in permeability after phenol treatment. Additionally, the decrease in TER correlated with changes in the distribution of a membrane raft marker, suggesting phenol-mediated effects on membrane fluidity. Such observations were independent of effects of phenol on cell viability as enhanced permeability occurred at doses of phenol that did not cause cell death. Overall, these findings suggest that phenol may affect transiently the lipid bilayer of the cell membrane, thus destabilizing TJ-containing microdomains. PMID:19679145

  9. Effects of phenol on barrier function of a human intestinal epithelial cell line correlate with altered tight junction protein localization

    SciTech Connect

    McCall, Ingrid C.; Betanzos, Abigail; Weber, Dominique A.; Nava, Porfirio; Miller, Gary W.; Parkos, Charles A.

    2009-11-15

    Phenol contamination of soil and water has raised concerns among people living near phenol-producing factories and hazardous waste sites containing the chemical. Phenol, particularly in high concentrations, is an irritating and corrosive substance, making mucosal membranes targets of toxicity in humans. However, few data on the effects of phenol after oral exposure exist. We used an in vitro model employing human intestinal epithelial cells (SK-CO15) cultured on permeable supports to examine effects of phenol on epithelial barrier function. We hypothesized that phenol disrupts epithelial barrier by altering tight junction (TJ) protein expression. The dose-response effect of phenol on epithelial barrier function was determined using transepithelial electrical resistance (TER) and FITC-dextran permeability measurements. We studied phenol-induced changes in cell morphology and expression of several tight junction proteins by immunofluorescence and Western blot analysis. Effects on cell viability were assessed by MTT, Trypan blue, propidium iodide and TUNEL staining. Exposure to phenol resulted in decreased TER and increased paracellular flux of FITC-dextran in a dose-dependent manner. Delocalization of claudin-1 and ZO-1 from TJs to cytosol correlated with the observed increase in permeability after phenol treatment. Additionally, the decrease in TER correlated with changes in the distribution of a membrane raft marker, suggesting phenol-mediated effects on membrane fluidity. Such observations were independent of effects of phenol on cell viability as enhanced permeability occurred at doses of phenol that did not cause cell death. Overall, these findings suggest that phenol may affect transiently the lipid bilayer of the cell membrane, thus destabilizing TJ-containing microdomains.

  10. Berberine Prevents Intestinal Mucosal Barrier Damage During Early Phase of Sepsis in Rat through the Toll-Like Receptors Signaling Pathway

    PubMed Central

    Li, Guo-xun; Wang, Xi-mo; Jiang, Tao; Gong, Jian-feng; Niu, Ling-ying

    2015-01-01

    Our previous study has shown berberine prevents damage to the intestinal mucosal barrier during early phase of sepsis in rat through mechanisms independent of the NOD-like receptors signaling pathway. In this study, we explored the regulatory effects of berberine on Toll-like receptors during the intestinal mucosal damaging process in rats. Male Sprague-Dawlay (SD) rats were treated with berberine for 5 d before undergoing cecal ligation and puncture (CLP) to induce polymicrobial sepsis. The expression of Toll-like receptor 2 (TLR 2), TLR 4, TLR 9, the activity of nuclear factor-kappa B (NF-κB), the levels of selected cytokines and chemokines, percentage of cell death in intestinal epithelial cells, and mucosal permeability were investigated at 0, 2, 6, 12 and 24 h after CLP. Results showed that the tumor necrosis factor-α (TNF-α ) and interleukin-6 (IL-6) level were significantly lower in berberine-treated rats compared to the control animals. Conversely, the expression level of tight junction proteins, percentage of cell death in intestinal epithelial cells and the mucosal permeability were significantly higher in berberine-treated rats. The mRNA expression of TLR 2, TLR 4, and TLR 9 were significantly affected by berberine treatment. Our results indicate that pretreatment with berberine attenuates tissue injury and protects the intestinal mucosal barrier in early phase of sepsis and this may possibly have been mediated through the TLRs pathway. PMID:25605990

  11. Mice lacking myosin IXb, an inflammatory bowel disease susceptibility gene, have impaired intestinal barrier function and superficial ulceration in the ileum.

    PubMed

    Hegan, Peter S; Chandhoke, Surjit K; Barone, Christina; Egan, Marie; Bähler, Martin; Mooseker, Mark S

    2016-04-01

    Genetic studies have implicated MYO9B, which encodes myosin IXb (Myo9b), a motor protein with a Rho GTPase activating domain (RhoGAP), as a susceptibility gene for inflammatory bowel disease (IBD). Moreover, we have recently shown that knockdown of Myo9b in an intestinal epithelial cell line impairs wound healing and barrier function. Here, we investigated whether mice lacking Myo9b have impaired intestinal barrier function and features of IBD. Myo9b knock out (KO) mice exhibit impaired weight gain and fecal occult blood (indicator of gastrointestinal bleeding), and increased intestinal epithelial cell apoptosis could be detected along the entire intestinal axis. Histologic analysis revealed intestinal mucosal damage, most consistently observed in the ileum, which included superficial ulceration and neutrophil infiltration. Focal lesions contained neutrophils and ultrastructural examination confirmed epithelial discontinuity and the deposition of extracellular matrix. We also observed impaired mucosal barrier function in KO mice. Transepithelial electrical resistance of KO ileum is >3 fold less than WT ileum. The intestinal mucosa is also permeable to high molecular weight dextran, presumably due to the presence of mucosal surface ulcerations. There is loss of tight junction-associated ZO-1, decreased lateral membrane associated E-cadherin, and loss of terminal web associated cytokeratin filaments. Consistent with increased Rho activity in the KO, there is increased subapical expression of activated myosin II (Myo2) based on localization of phosphorylated Myo2 regulatory light chain. Except for a delay in disease onset in the KO, no difference in dextran sulfate sodium-induced colitis and lethality was observed between wild-type and Myo9b KO mice. © 2016 Wiley Periodicals, Inc. PMID:26972322

  12. Human Oral Isolate Lactobacillus fermentum AGR1487 Reduces Intestinal Barrier Integrity by Increasing the Turnover of Microtubules in Caco-2 Cells

    PubMed Central

    Anderson, Rachel C.; Young, Wayne; Clerens, Stefan; Cookson, Adrian L.; McCann, Mark J.; Armstrong, Kelly M.; Roy, Nicole C.

    2013-01-01

    Lactobacillus fermentum is found in fermented foods and thought to be harmless. In vivo and clinical studies indicate that some L. fermentum strains have beneficial properties, particularly for gastrointestinal health. However, L. fermentum AGR1487 decreases trans-epithelial electrical resistance (TEER), a measure of intestinal barrier integrity. The hypothesis was that L. fermentum AGR1487 decreases the expression of intestinal cell tight junction genes and proteins, thereby reducing barrier integrity. Transcriptomic and proteomic analyses of Caco-2 cells (model of human intestinal epithelial cells) treated with L. fermentum AGR1487 were used to obtain a global view of the effect of the bacterium on intestinal epithelial cells. Specific functional characteristics by which L. fermentum AGR1487 reduces intestinal barrier integrity were examined using confocal microscopy, cell cycle progression and adherence bioassays. The effects of TEER-enhancing L. fermentum AGR1485 were investigated for comparison. L. fermentum AGR1487 did not alter the expression of Caco-2 cell tight junction genes (compared to L. fermentum AGR1485) and tight junction proteins were not able to be detected. However, L. fermentum AGR1487 increased the expression levels of seven tubulin genes and the abundance of three microtubule-associated proteins, which have been linked to tight junction disassembly. Additionally, Caco-2 cells treated with L. fermentum AGR1487 did not have defined and uniform borders of zona occludens 2 around each cell, unlike control or AGR1485 treated cells. L. fermentum AGR1487 cells were required for the negative effect on barrier integrity (bacterial supernatant did not cause a decrease in TEER), suggesting that a physical interaction may be necessary. Increased adherence of L. fermentum AGR1487 to Caco-2 cells (compared to L. fermentum AGR1485) was likely to facilitate this cell-to-cell interaction. These findings illustrate that bacterial strains of the same species can

  13. Protective effects of ψ taraxasterol 3-O-myristate and arnidiol 3-O-myristate isolated from Calendula officinalis on epithelial intestinal barrier.

    PubMed

    Dall'Acqua, Stefano; Catanzaro, Daniela; Cocetta, Veronica; Igl, Nadine; Ragazzi, Eugenio; Giron, Maria Cecilia; Cecconello, Laura; Montopoli, Monica

    2016-03-01

    The triterpene esters ᴪ taraxasterol-3-O-myristate (1) and arnidiol-3-O-myristate (2) were tested for their ability to protect epithelial intestinal barrier in an in vitro model. Their effects on ROS production and on trans-epithelial resistance were investigated on CaCo-2 cell monolayers both in basal and stress-induced conditions. Both compounds were able to modulate the stress damage induced by H2O2 and INFγ+TNFα, showing a potential use as model compounds for the study of new therapeutic agents for intestinal inflammations. PMID:26791917

  14. Impact of oral bisphenol A at reference doses on intestinal barrier function and sex differences after perinatal exposure in rats.

    PubMed

    Braniste, Viorica; Jouault, Aurore; Gaultier, Eric; Polizzi, Arnaud; Buisson-Brenac, Claire; Leveque, Mathilde; Martin, Pascal G; Theodorou, Vassilia; Fioramonti, Jean; Houdeau, Eric

    2010-01-01

    Bisphenol A (BPA), a chemical estrogen widely used in the food-packaging industry and baby bottles, is recovered in human fluids (0.1-10 nM). Recent studies have reported that BPA is hormonally active at low doses, emphasizing the debate of a risk for human health. Estrogen receptors are expressed in the colon, and although the major route of BPA exposure is food, the effects on gut have received no attention. We first examined the endocrine disrupting potency of BPA on colonic paracellular permeability (CPP), experimental colitis, and visceral sensitivity in ovariectomized rats orally exposed to 5 mg/kg/d BPA (i.e., the no observed adverse effect level), 50 microg/kg/d BPA (i.e., tolerable daily intake), or lower doses. BPA dose-dependently decreased basal CPP, with a half-maximal inhibitory dose of 5.2 microg/kg/d, 10-fold below the tolerable daily intake. This correlated with an increase in epithelial tight junction sealing, also observed in Caco-2 cells exposed to 10 nM BPA. When ovariectomized rats were fed with BPA at the no observed adverse effect level, the severity of colitis was reduced, whereas the same dose increased pain sensitivity to colorectal stimuli. We then examined the impact of perinatal exposure to BPA on intestinal permeability and inflammatory response in the offspring. In female rats, but not in male rats, perinatal BPA evoked a decrease of CPP in adulthood, whereas the proinflammatory response of colonic mucosa was strengthened. This study first demonstrates that the xenoestrogen BPA at reference doses influences intestinal barrier function and gut nociception. Moreover, perinatal exposure promotes the development of severe inflammation in adult female offspring only. PMID:20018722

  15. Intestinal barrier function of Atlantic salmon (Salmo salar L.) post smolts is reduced by common sea cage environments and suggested as a possible physiological welfare indicator

    PubMed Central

    2010-01-01

    Background Fish farmed under high intensity aquaculture conditions are subjected to unnatural environments that may cause stress. Therefore awareness of how to maintain good health and welfare of farmed fish is important. For Atlantic salmon held in sea cages, water flow, dissolved oxygen (DO) levels and temperature will fluctuate over time and the fish can at times be exposed to detrimentally low DO levels and high temperatures. This experimental study investigates primary and secondary stress responses of Atlantic salmon post smolts to long-term exposure to reduced and fluctuating DO levels and high water temperatures, mimicking situations in the sea cages. Plasma cortisol levels and cortisol release to the water were assessed as indicators of the primary stress response and intestinal barrier integrity and physiological functions as indicators of secondary responses to changes in environmental conditions. Results Plasma cortisol levels were elevated in fish exposed to low (50% and 60% saturation) DO levels and low temperature (9°C), at days 9, 29 and 48. The intestinal barrier function, measured as electrical resistance (TER) and permeability of mannitol at the end of the experiment, were reduced at 50% DO, in both proximal and distal intestine. When low DO levels were combined with high temperature (16°C), plasma cortisol levels were elevated in the cyclic 1:5 h at 85%:50% DO group and fixed 50% DO group compared to the control (85% DO) group at day 10 but not at later time points. The intestinal barrier function was clearly disturbed in the 50% DO group; TER was reduced in both intestinal regions concomitant with increased paracellular permeability in the distal region. Conclusions This study reveals that adverse environmental conditions (low water flow, low DO levels at low and high temperature), that can occur in sea cages, elicits primary and secondary stress responses in Atlantic salmon post smolts. The intestinal barrier function was significantly

  16. Physiological and pathophysiological factors affecting the expression and activity of the drug transporter MRP2 in intestine. Impact on its function as membrane barrier.

    PubMed

    Arana, Maite R; Tocchetti, Guillermo N; Rigalli, Juan P; Mottino, Aldo D; Villanueva, Silvina S M

    2016-07-01

    The gastrointestinal epithelium functions as a selective barrier to absorb nutrients, electrolytes and water, but at the same time restricts the passage into the systemic circulation of intraluminal potentially toxic compounds. This epithelium maintains its selective barrier function through the presence of very selective and complex intercellular junctions and the ability of the absorptive cells to reject those compounds. Accordingly, the enterocytes metabolize orally incorporated xenobiotics and secrete the hydrophilic metabolites back into the intestinal lumen through specific transporters localized apically. In the recent decades, there has been increasing recognition of the existence of the intestinal cellular barrier. In the present review we focus on the role of the multidrug resistance-associated protein 2 (MRP2, ABCC2) in the apical membrane of the enterocytes, as an important component of this intestinal barrier, as well as on its regulation. We provide a detailed compilation of significant contributions demonstrating that MRP2 expression and function vary under relevant physiological and pathophysiological conditions. Because MRP2 activity modulates the availability and pharmacokinetics of many therapeutic drugs administered orally, their therapeutic efficacy and safety may vary as well. PMID:27109321

  17. Chemokines and chemokine receptors in mucosal homeostasis at the intestinal epithelial barrier in inflammatory bowel disease.

    PubMed

    Zimmerman, Noah P; Vongsa, Rebecca A; Wendt, Michael K; Dwinell, Michael B

    2008-07-01

    Chemokines, a large family of small chemoattractive cytokines, and their receptors play an integral role in the regulation of the immune response and homeostasis. The ability of chemokines to attract specific populations of immune cells sets them apart from other chemoattractants. Chemokines produced within the gastrointestinal mucosa are critical players in directing the balance between physiological and pathophysiological inflammation in health, inflammatory bowel disease (IBD), and the progression to colon cancer. In addition to the well-characterized role of chemokines in directed trafficking of immune cells to the gut mucosa, the expression of chemokine receptors on the cells of the epithelium makes them active participants in the chemokine signaling network. Recent findings demonstrate an important role for chemokines and chemokine receptors in epithelial barrier repair and maintenance as well as an intricate involvement in limiting metastasis of colonic carcinoma. Increased recognition of the association between barrier defects and inflammation and the subsequent progression to cancer in IBD thus implicates chemokines as key regulators of mucosal homeostasis and disease pathogenesis. PMID:18452220

  18. Lactobacillus plantarum MB452 enhances the function of the intestinal barrier by increasing the expression levels of genes involved in tight junction formation

    PubMed Central

    2010-01-01

    Background Intestinal barrier function is important for preserving health, as a compromised barrier allows antigen entry and can induce inflammatory diseases. Probiotic bacteria can play a role in enhancing intestinal barrier function; however, the mechanisms are not fully understood. Existing studies have focused on the ability of probiotics to prevent alterations to tight junctions in disease models, and have been restricted to a few tight junction bridging proteins. No studies have previously investigated the effect of probiotic bacteria on healthy intestinal epithelial cell genes involved in the whole tight junction signalling pathway, including those encoding for bridging, plaque and dual location tight junction proteins. Alteration of tight junction signalling in healthy humans is a potential mechanism that could lead to the strengthening of the intestinal barrier, resulting in limiting the ability of antigens to enter the body and potentially triggering undesirable immune responses. Results The effect of Lactobacillus plantarum MB452 on tight junction integrity was determined by measuring trans-epithelial electrical resistance (TEER) across Caco-2 cell layers. L. plantarum MB452 caused a dose-dependent TEER increase across Caco-2 cell monolayers compared to control medium. Gene expression was compared in Caco-2 cells untreated or treated with L. plantarum MB452 for 10 hours. Caco-2 cell RNA was hybridised to human oligonucleotide arrays. Data was analysed using linear models and differently expressed genes were examined using pathway analysis tools. Nineteen tight junction-related genes had altered expression levels in response to L. plantarum MB452 (modified-P < 0.05, fold-change > 1.2), including those encoding occludin and its associated plaque proteins that anchor it to the cytoskeleton. L. plantarum MB452 also caused changes in tubulin and proteasome gene expression levels which may be linked to intestinal barrier function. Caco-2 tight junctions were

  19. Lactobacillus rhamnosus GG reduces hepatic TNFα production and inflammation in chronic alcohol-induced liver injury.

    PubMed

    Wang, Yuhua; Liu, Yanlong; Kirpich, Irina; Ma, Zhenhua; Wang, Cuiling; Zhang, Min; Suttles, Jill; McClain, Craig; Feng, Wenke

    2013-09-01

    The therapeutic effects of probiotic treatment in alcoholic liver disease (ALD) have been studied in both patients and experimental animal models. Although the precise mechanisms of the pathogenesis of ALD are not fully understood, gut-derived endotoxin has been postulated to play a crucial role in hepatic inflammation. Previous studies have demonstrated that probiotic therapy reduces circulating endotoxin derived from intestinal gram-negative bacteria in ALD. In this study, we investigated the effects of probiotics on hepatic tumor necrosis factor-α (TNFα) production and inflammation in response to chronic alcohol ingestion. Mice were fed Lieber DeCarli liquid diet containing 5% alcohol for 8weeks, and Lactobacillus rhamnosus GG (LGG) was supplemented in the last 2 weeks. Eight-week alcohol feeding caused a significant increase in hepatic inflammation as shown by histological assessment and hepatic tissue myeloperoxidase activity assay. Two weeks of LGG supplementation reduced hepatic inflammation and liver injury and markedly reduced TNFα expression. Alcohol feeding increased hepatic mRNA expression of Toll-like receptors (TLRs) and CYP2E1 and decreased nuclear factor erythroid 2-related factor 2 expression. LGG supplementation attenuated these changes. Using human peripheral blood monocytes-derived macrophages, we also demonstrated that incubation with ethanol primes both lipopolysaccharide- and flagellin-induced TNFα production, and LGG culture supernatant reduced this induction in a dose-dependent manner. In addition, LGG treatment also significantly decreased alcohol-induced phosphorylation of p38 MAP kinase. In conclusion, probiotic LGG treatment reduced alcohol-induced hepatic inflammation by attenuation of TNFα production via inhibition of TLR4- and TLR5-mediated endotoxin activation. PMID:23618528

  20. Dietary Lactobacillus rhamnosus GG Supplementation Improves the Mucosal Barrier Function in the Intestine of Weaned Piglets Challenged by Porcine Rotavirus

    PubMed Central

    Mao, Xiangbing; Gu, Changsong; Hu, Haiyan; Tang, Jun; Chen, Daiwen; Yu, Bing; He, Jun; Yu, Jie; Luo, Junqiu; Tian, Gang

    2016-01-01

    Lactobacillus rhamnosus GG (LGG) has been regarded as a safe probiotic strain. The aim of this study was to investigate whether dietary LGG supplementation could alleviate diarrhea via improving jejunal mucosal barrier function in the weaned piglets challenged by RV, and further analyze the potential roles for apoptosis of jejunal mucosal cells and intestinal microbiota. A total of 24 crossbred barrows weaned at 21 d of age were assigned randomly to 1 of 2 diets: the basal diet and LGG supplementing diet. On day 11, all pigs were orally infused RV or the sterile essential medium. RV infusion increased the diarrhea rate, increased the RV-Ab, NSP4 and IL-2 concentrations and the Bax mRNA levels of jejunal mucosa (P<0.05), decreased the villus height, villus height: crypt depth, the sIgA, IL-4 and mucin 1 concentrations and the ZO-1, occludin and Bcl-2 mRNA levels of jejunal mucosa (P<0.05), and affected the microbiota of ileum and cecum (P<0.05) in the weaned pigs. Dietary LGG supplementation increased the villus height and villus height: crypt depth, the sIgA, IL-4, mucin 1 and mucin 2 concentrations, and the ZO-1, occludin and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05) reduced the Bax mRNA levels of the jejunal mucosa (P<0.05) in weaned pigs. Furthermore, dietary LGG supplementation alleviated the increase of diarrhea rate in the weaned pigs challenged by RV (P<0.05), and relieve the effect of RV infection on the villus height, crypt depth and the villus height: crypt depth of the jejunal mucosa (P<0.05), the NSP4, sIgA, IL-2, IL-4, mucin 1 and mucin 2 concentrations of jejunal mucosa (P<0.05), the ZO-1, occludin, Bax and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05), and the microbiota of ileum and cecum (P<0.05) in the weaned pigs challenged by RV. These results suggest that supplementing LGG in diets alleviated the diarrhea of weaned piglets challenged by RV via inhibiting the virus multiplication and improving the jejunal mucosal barrier function

  1. Dietary Lactobacillus rhamnosus GG Supplementation Improves the Mucosal Barrier Function in the Intestine of Weaned Piglets Challenged by Porcine Rotavirus.

    PubMed

    Mao, Xiangbing; Gu, Changsong; Hu, Haiyan; Tang, Jun; Chen, Daiwen; Yu, Bing; He, Jun; Yu, Jie; Luo, Junqiu; Tian, Gang

    2016-01-01

    Lactobacillus rhamnosus GG (LGG) has been regarded as a safe probiotic strain. The aim of this study was to investigate whether dietary LGG supplementation could alleviate diarrhea via improving jejunal mucosal barrier function in the weaned piglets challenged by RV, and further analyze the potential roles for apoptosis of jejunal mucosal cells and intestinal microbiota. A total of 24 crossbred barrows weaned at 21 d of age were assigned randomly to 1 of 2 diets: the basal diet and LGG supplementing diet. On day 11, all pigs were orally infused RV or the sterile essential medium. RV infusion increased the diarrhea rate, increased the RV-Ab, NSP4 and IL-2 concentrations and the Bax mRNA levels of jejunal mucosa (P<0.05), decreased the villus height, villus height: crypt depth, the sIgA, IL-4 and mucin 1 concentrations and the ZO-1, occludin and Bcl-2 mRNA levels of jejunal mucosa (P<0.05), and affected the microbiota of ileum and cecum (P<0.05) in the weaned pigs. Dietary LGG supplementation increased the villus height and villus height: crypt depth, the sIgA, IL-4, mucin 1 and mucin 2 concentrations, and the ZO-1, occludin and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05) reduced the Bax mRNA levels of the jejunal mucosa (P<0.05) in weaned pigs. Furthermore, dietary LGG supplementation alleviated the increase of diarrhea rate in the weaned pigs challenged by RV (P<0.05), and relieve the effect of RV infection on the villus height, crypt depth and the villus height: crypt depth of the jejunal mucosa (P<0.05), the NSP4, sIgA, IL-2, IL-4, mucin 1 and mucin 2 concentrations of jejunal mucosa (P<0.05), the ZO-1, occludin, Bax and Bcl-2 mRNA levels of the jejunal mucosa (P<0.05), and the microbiota of ileum and cecum (P<0.05) in the weaned pigs challenged by RV. These results suggest that supplementing LGG in diets alleviated the diarrhea of weaned piglets challenged by RV via inhibiting the virus multiplication and improving the jejunal mucosal barrier function

  2. Modulation of Cytochrome P450 Metabolism and Transport across Intestinal Epithelial Barrier by Ginger Biophenolics

    PubMed Central

    Yang, Chunhua; Donthamsetty, Shashikiran; Cantuaria, Guilherme; Jadhav, Gajanan R.; Vangala, Subrahmanyam; Reid, Michelle D.; Aneja, Ritu

    2014-01-01

    Natural and complementary therapies in conjunction with mainstream cancer care are steadily gaining popularity. Ginger extract (GE) confers significant health-promoting benefits owing to complex additive and/or synergistic interactions between its bioactive constituents. Recently, we showed that preservation of natural “milieu” confers superior anticancer activity on GE over its constituent phytochemicals, 6-gingerol (6G), 8-gingerol (8G), 10-gingerol (10G) and 6-shogaol (6S), through enterohepatic recirculation. Here we further evaluate and compare the effects of GE and its major bioactive constituents on cytochrome P450 (CYP) enzyme activity in human liver microsomes by monitoring metabolites of CYP-specific substrates using LC/MS/MS detection methods. Our data demonstrate that individual gingerols are potent inhibitors of CYP isozymes, whereas GE exhibits a much higher half-maximal inhibition value, indicating no possible herb-drug interactions. However, GE's inhibition of CYP1A2 and CYP2C8 reflects additive interactions among the constituents. In addition, studies performed to evaluate transporter-mediated intestinal efflux using Caco-2 cells revealed that GE and its phenolics are not substrates of P-glycoprotein (Pgp). Intriguingly, however, 10G and 6S were not detected in the receiver compartment, indicating possible biotransformation across the Caco-2 monolayer. These data strengthen the notion that an interplay of complex interactions among ginger phytochemicals when fed as whole extract dictates its bioactivity highlighting the importance of consuming whole foods over single agents. Our study substantiates the need for an in-depth analysis of hepatic biotransformation events and distribution profiles of GE and its active phenolics for the design of safe regimens. PMID:25251219

  3. Influence of sodium on major diffusion barriers to passive intestinal uptake.

    PubMed

    Thomson, A B

    1982-08-01

    Intestinal active transport processes have been shown to be sodium dependent, but the effect of varying the concentration of sodium in the luminal bulk phase on the passive uptake of lipids has not been established. An in vitro technique was used to measure the uptake of fatty acids and alcohols into the rabbit jejunum under conditions of stirring of the bulk phase selected to reduce the effective resistance of the unstirred water layer (UWL). Sodium withdrawal had no effect on the uptake of a homologous series of fatty alcohols, and thus the UWL was not influenced by varying bulk-phase sodium; in contrast, the uptake of a homologous series of short-, medium, and long-chain-length saturated fatty acids (FA) was progressively inhibited by reducing bulk-phase sodium from 145 to 0 meq/l. There was no difference in FA uptake between the use of magnesium chloride and mannitol for maintenance of isotonicity with sodium withdrawal. At each sodium concentration, the uptake of FA rose with increasing FA chain length. The relation between sodium concentration and incremental change in free energy (delta delta Fw leads to 1) was described by a sigmoid-shaped curve. The uptake of cholesterol was also inhibited by reducing sodium in the bulk phase. In summary, varying bulk-phase sodium has no effect on UWL, and the influence of sodium on the uptake of FA is mediated by altering delta delta Fw leads to 1 and therefore the physicochemical properties of the brush-border membrane. PMID:7114222

  4. Interleukin-6 induces keratin expression in intestinal epithelial cells: potential role of keratin-8 in interleukin-6-induced barrier function alterations.

    PubMed

    Wang, Lixin; Srinivasan, Shanthi; Theiss, Arianne L; Merlin, Didier; Sitaraman, Shanthi V

    2007-03-16

    Keratin 8 (K8) and keratin-18 (K18) are the major intermediate filament proteins in the intestinal epithelia. The regulation and function of keratin in the intestinal epithelia is largely unknown. In this study we addressed the role and regulation of K8 and K18 expression by interleukin 6 (IL-6). Caco2-BBE cell line and IL-6 null mice were used to study the effect of IL-6 on keratin expression. Keratin expression was studied by Northern blot, Western blot, and confocal microscopy. Paracellular permeability was assessed by apical-to-basal transport of a fluorescein isothiocyanate dextran probe (FD-4). K8 was silenced using the small interfering RNA approach. IL-6 significantly up-regulated mRNA and protein levels of K8 and K18. Confocal microscopy showed a reticular pattern of intracellular keratin localized to the subapical region after IL-6 treatment. IL-6 also induced serine phosphorylation of K8. IL-6 decreased paracellular flux of FD-4 compared with vehicle-treated monolayers. K8 silencing abolished the decrease in paracellular permeability induced by IL-6. Administration of dextran sodium sulfate (DSS) significantly increased intestinal permeability in IL-6-/- mice compared with wild type mice given DSS. Collectively, our data demonstrate that IL-6 regulates the colonic expression of K8 and K18, and K8/K18 mediates barrier protection by IL-6 under conditions where intestinal barrier is compromised. Thus, our data uncover a novel function of these abundant cytoskeletal proteins, which may have implications in intestinal disorders such as inflammatory bowel disease wherein barrier dysfunction underlies the inflammatory response. PMID:17213200

  5. MyD88 adaptor-like (Mal) functions in the epithelial barrier and contributes to intestinal integrity via protein kinase C.

    PubMed

    Corr, S C; Palsson-McDermott, E M; Grishina, I; Barry, S P; Aviello, G; Bernard, N J; Casey, P G; Ward, J B J; Keely, S J; Dandekar, S; Fallon, P G; O'Neill, L A J

    2014-01-01

    MyD88 adapter-like (Mal)-deficient mice displayed increased susceptibility to oral but not intraperitoneal infection with Salmonella Typhimurium. Bone marrow chimeras demonstrated that mice with Mal-deficient non-hematopoietic cells were more susceptible to infection, indicating a role for Mal in non-myeloid cells. We observed perturbed barrier function in Mal(-/-) mice, as indicated by reduced electrical resistance and increased mucosa blood permeability following infection. Altered expression of occludin, Zonula occludens-1, and claudin-3 in intestinal epithelia from Mal(-/-) mice suggest that Mal regulates tight junction formation, which may in part contribute to intestinal integrity. Mal interacted with several protein kinase C (PKC) isoforms in a Caco-2 model of intestinal epithelia and inhibition of Mal or PKC increased permeability and bacterial invasion via a paracellular route, while a pan-PKC inhibitor increased susceptibility to oral infection in mice. Mal signaling is therefore beneficial to the integrity of the intestinal barrier during infection. PMID:23612054

  6. Malaria-associated L-arginine deficiency induces mast cell-associated disruption to intestinal barrier defenses against nontyphoidal Salmonella bacteremia.

    PubMed

    Chau, Jennifer Y; Tiffany, Caitlin M; Nimishakavi, Shilpa; Lawrence, Jessica A; Pakpour, Nazzy; Mooney, Jason P; Lokken, Kristen L; Caughey, George H; Tsolis, Renee M; Luckhart, Shirley

    2013-10-01

    Coinfection with malaria and nontyphoidal Salmonella serotypes (NTS) can cause life-threatening bacteremia in humans. Coinfection with malaria is a recognized risk factor for invasive NTS, suggesting that malaria impairs intestinal barrier function. Here, we investigated mechanisms and strategies for prevention of coinfection pathology in a mouse model. Our findings reveal that malarial-parasite-infected mice, like humans, develop L-arginine deficiency, which is associated with intestinal mastocytosis, elevated levels of histamine, and enhanced intestinal permeability. Prevention or reversal of L-arginine deficiency blunts mastocytosis in ileal villi as well as bacterial translocation, measured as numbers of mesenteric lymph node CFU of noninvasive Escherichia coli Nissle and Salmonella enterica serotype Typhimurium, the latter of which is naturally invasive in mice. Dietary supplementation of malarial-parasite-infected mice with L-arginine or L-citrulline reduced levels of ileal transcripts encoding interleukin-4 (IL-4), a key mediator of intestinal mastocytosis and macromolecular permeability. Supplementation with L-citrulline also enhanced epithelial adherens and tight junctions in the ilea of coinfected mice. These data suggest that increasing L-arginine bioavailability via oral supplementation can ameliorate malaria-induced intestinal pathology, providing a basis for testing nutritional interventions to reduce malaria-associated mortality in humans. PMID:23690397

  7. Malaria-Associated l-Arginine Deficiency Induces Mast Cell-Associated Disruption to Intestinal Barrier Defenses against Nontyphoidal Salmonella Bacteremia

    PubMed Central

    Chau, Jennifer Y.; Tiffany, Caitlin M.; Nimishakavi, Shilpa; Lawrence, Jessica A.; Pakpour, Nazzy; Mooney, Jason P.; Lokken, Kristen L.; Caughey, George H.; Tsolis, Renee M.

    2013-01-01

    Coinfection with malaria and nontyphoidal Salmonella serotypes (NTS) can cause life-threatening bacteremia in humans. Coinfection with malaria is a recognized risk factor for invasive NTS, suggesting that malaria impairs intestinal barrier function. Here, we investigated mechanisms and strategies for prevention of coinfection pathology in a mouse model. Our findings reveal that malarial-parasite-infected mice, like humans, develop l-arginine deficiency, which is associated with intestinal mastocytosis, elevated levels of histamine, and enhanced intestinal permeability. Prevention or reversal of l-arginine deficiency blunts mastocytosis in ileal villi as well as bacterial translocation, measured as numbers of mesenteric lymph node CFU of noninvasive Escherichia coli Nissle and Salmonella enterica serotype Typhimurium, the latter of which is naturally invasive in mice. Dietary supplementation of malarial-parasite-infected mice with l-arginine or l-citrulline reduced levels of ileal transcripts encoding interleukin-4 (IL-4), a key mediator of intestinal mastocytosis and macromolecular permeability. Supplementation with l-citrulline also enhanced epithelial adherens and tight junctions in the ilea of coinfected mice. These data suggest that increasing l-arginine bioavailability via oral supplementation can ameliorate malaria-induced intestinal pathology, providing a basis for testing nutritional interventions to reduce malaria-associated mortality in humans. PMID:23690397

  8. Enteropathogenic Escherichia coli inhibits type I interferon- and RNase L-mediated host defense to disrupt intestinal epithelial cell barrier function.

    PubMed

    Long, Tiha M; Nisa, Shahista; Donnenberg, Michael S; Hassel, Bret A

    2014-07-01

    Enteropathogenic Escherichia coli (EPEC) primarily infects children in developing countries and causes diarrhea that can be deadly. EPEC pathogenesis occurs through type III secretion system (T3SS)-mediated injection of effectors into intestinal epithelial cells (IECs); these effectors alter actin dynamics, modulate the immune response, and disrupt tight junction (TJ) integrity. The resulting compromised barrier function and increased gastrointestinal (GI) permeability may be responsible for the clinical symptoms of infection. Type I interferon (IFN) mediates anti-inflammatory activities and serves essential functions in intestinal immunity and homeostasis; however, its role in the immune response to enteric pathogens, such as EPEC, and its impact on IEC barrier function have not been examined. Here, we report that IFN-β is induced following EPEC infection and regulates IEC TJ proteins to maintain barrier function. The EPEC T3SS effector NleD counteracts this protective activity by inhibiting IFN-β induction and enhancing tumor necrosis factor alpha to promote barrier disruption. The endoribonuclease RNase L is a key mediator of IFN induction and action that promotes TJ protein expression and IEC barrier integrity. EPEC infection inhibits RNase L in a T3SS-dependent manner, providing a mechanism by which EPEC evades IFN-induced antibacterial activities. This work identifies novel roles for IFN-β and RNase L in IEC barrier functions that are targeted by EPEC effectors to escape host defense mechanisms and promote virulence. The IFN-RNase L axis thus represents a potential therapeutic target for enteric infections and GI diseases involving compromised barrier function. PMID:24733098

  9. Genetic susceptibility factors for alcohol-induced chronic pancreatitis.

    PubMed

    Aghdassi, Ali A; Weiss, F Ulrich; Mayerle, Julia; Lerch, Markus M; Simon, Peter

    2015-07-01

    Chronic pancreatitis is a progressive inflammatory disease of the pancreas and frequently associated with immoderate alcohol consumption. Since only a small proportion of alcoholics eventually develop chronic pancreatitis genetic susceptibility factors have long been suspected to contribute to the pathogenesis of the disease. Smaller studies in ethnically defined populations have found that not only polymorphism in proteins involved in the metabolism of ethanol, such as Alcohol Dehydrogenase and Aldehyde Dehydrogenase, can confer a risk for developing chronic pancreatitis but also mutations that had previously been reported in association with idiopathic pancreatitis, such as SPINK1 mutations. In a much broader approach employing genome wide search strategies the NAPS study found that polymorphisms in the Trypsin locus (PRSS1 rs10273639), and the Claudin 2 locus (CLDN2-RIPPLY1-MORC4 locus rs7057398 and rs12688220) confer an increased risk of developing alcohol-induced pancreatitis. These results from North America have now been confirmed by a European consortium. In another genome wide approach polymorphisms in the genes encoding Fucosyltransferase 2 (FUT2) non-secretor status and blood group B were not only found in association with higher serum lipase levels in healthy volunteers but also to more than double the risk for developing alcohol-associated chronic pancreatitis. These novel genetic associations will allow to investigate the pathophysiological and biochemical basis of alcohol-induced chronic pancreatitis on a cellular level and in much more detail than previously possible. PMID:26149858

  10. Candida albicans infection leads to barrier breakdown and a MAPK/NF-κB mediated stress response in the intestinal epithelial cell line C2BBe1.

    PubMed

    Böhringer, Michael; Pohlers, Susann; Schulze, Sylvie; Albrecht-Eckardt, Daniela; Piegsa, Judith; Weber, Michael; Martin, Ronny; Hünniger, Kerstin; Linde, Jörg; Guthke, Reinhard; Kurzai, Oliver

    2016-07-01

    Intestinal epithelial cells (IEC) form a tight barrier to the gut lumen. Paracellular permeability of the intestinal barrier is regulated by tight junction proteins and can be modulated by microorganisms and other stimuli. The polymorphic fungus Candida albicans, a frequent commensal of the human mucosa, has the capacity of traversing this barrier and establishing systemic disease within the host. Infection of polarized C2BBe1 IEC with wild-type C. albicans led to a transient increase of transepithelial electric resistance (TEER) before subsequent barrier disruption, accompanied by a strong decline of junctional protein levels and substantial, but considerably delayed cytotoxicity. Time-resolved microarray-based transcriptome analysis of C. albicans challenged IEC revealed a prominent role of NF-κB and MAPK signalling pathways in the response to infection. Hence, we inferred a gene regulatory network based on differentially expressed NF-κB and MAPK pathway components and their predicted transcriptional targets. The network model predicted activation of GDF15 by NF-κB was experimentally validated. Furthermore, inhibition of NF-κB activation in C. albicans infected C2BBe1 cells led to enhanced cytotoxicity in the epithelial cells. Taken together our study identifies NF-κB activation as an important protective signalling pathway in the response of epithelial cells to C. albicans. PMID:26752615

  11. Changes in intestinal barrier function and gut microbiota in high-fat diet-fed rats are dynamic and region dependent.

    PubMed

    Hamilton, M Kristina; Boudry, Gaëlle; Lemay, Danielle G; Raybould, Helen E

    2015-05-15

    A causal relationship between the pathophysiological changes in the gut epithelium and altered gut microbiota with the onset of obesity have been suggested but not defined. The aim of this study was to determine the temporal relationship between impaired intestinal barrier function and microbial dysbiosis in the small and large intestine in rodent high-fat (HF) diet-induced obesity. Rats were fed HF diet (45% fat) or normal chow (C, 10% fat) for 1, 3, or 6 wk; food intake, body weight, and adiposity were measured. Barrier function ex vivo using FITC-labeled dextran (4,000 Da, FD-4) and horseradish peroxidase (HRP) probes in Ussing chambers, gene expression, and gut microbial communities was assessed. After 1 wk, there was an immediate but reversible increase in paracellular permeability, decrease in IL-10 expression, and decrease in abundance of genera within the class Clostridia in the ileum. In the large intestine, HRP flux and abundance of genera within the order Bacteroidales increased with time on the HF diet and correlated with the onset of increased body weight and adiposity. The data show immediate insults in the ileum in response to ingestion of a HF diet, which were rapidly restored and preceded increased passage of large molecules across the large intestinal epithelium. This study provides an understanding of microbiota dysbiosis and gut pathophysiology in diet-induced obesity and has identified IL-10 and Oscillospira in the ileum and transcellular flux in the large intestine as potential early impairments in the gut that might lead to obesity and metabolic disorders. PMID:25747351

  12. The intestinal microbiome, barrier function, and immune system in inflammatory bowel disease: a tripartite pathophysiological circuit with implications for new therapeutic directions

    PubMed Central

    Vindigni, Stephen M.; Zisman, Timothy L.; Suskind, David L.; Damman, Christopher J.

    2016-01-01

    We discuss the tripartite pathophysiological circuit of inflammatory bowel disease (IBD), involving the intestinal microbiota, barrier function, and immune system. Dysfunction in each of these physiological components (dysbiosis, leaky gut, and inflammation) contributes in a mutually interdependent manner to IBD onset and exacerbation. Genetic and environmental risk factors lead to disruption of gut homeostasis: genetic risks predominantly affect the immune system, environmental risks predominantly affect the microbiota, and both affect barrier function. Multiple genetic and environmental ‘hits’ are likely necessary to establish and exacerbate disease. Most conventional IBD therapies currently target only one component of the pathophysiological circuit, inflammation; however, many patients with IBD do not respond to immune-modulating therapies. Hope lies in new classes of therapies that target the microbiota and barrier function. PMID:27366227

  13. Supplementing formula-fed piglets with a low molecular weight fraction of bovine colostrum whey results in an improved intestinal barrier.

    PubMed

    De Vos, M; Huygelen, V; Van Raemdonck, G; Willemen, S; Fransen, E; Van Ostade, X; Casteleyn, C; Van Cruchten, S; Van Ginneken, C

    2014-08-01

    To test the hypothesis that a low molecular weight fraction of colostral whey could affect the morphology and barrier function of the small intestine, 30 3-d-old piglets (normal or low birth weight) were suckled (n = 5), artificially fed with milk formula (n = 5), or artificially fed with milk formula with a low molecular weight fraction of colostral whey (n = 5) until 10 d of age. The small intestine was sampled for histology (haematoxylin and eosin stain; anti-KI67 immunohistochemistry) and enzyme activities (aminopeptidase A, aminopeptidase N, dipeptidylpeptidase IV, lactase, maltase, and sucrase). In addition, intestinal permeability was evaluated via a dual sugar absorption test and via the measurement of occludin abundance. Artificially feeding of piglets reduced final BW (P < 0.001), villus height (P < 0.001), lactase (P < 0.001), and dipeptidylpeptidase IV activities (P < 0.07), whereas crypt depth (P < 0.001) was increased. No difference was observed with regard to the permeability measurements when comparing artificially fed with naturally suckling piglets. Supplementing piglets with the colostral whey fraction did not affect BW, enzyme activities, or the outcome of the dual sugar absorption test. On the contrary, the small intestines of supplemented piglets had even shorter villi (P = 0.001) than unsupplemented piglets and contained more occludin (P = 0.002). In conclusion, at 10 d of age, no differences regarding intestinal morphology and permeability measurements were observed between the 2 BW categories. In both weight categories, the colostral whey fraction affected the morphology of the small intestine but did not improve the growth performances or the in vivo permeability. These findings should be acknowledged when developing formulated milk for neonatal animals with the aim of improving the performance of low birth weight piglets. PMID:25012977

  14. Evaluation of In Vitro Anti-Inflammatory Activities and Protective Effect of Fermented Preparations of Rhizoma Atractylodis Macrocephalae on Intestinal Barrier Function against Lipopolysaccharide Insult

    PubMed Central

    Bose, Shambhunath; Kim, Hojun

    2013-01-01

    Lipopolysaccharide (LPS), a potent inducer of systemic inflammatory responses, is known to cause impairment of intestinal barrier function. Here, we evaluated the in vitro protective effect of an unfermented formulation of Rhizoma Atractylodis Macrocephalae (RAM), a traditional Chinese herbal medicine widely used in the treatment of many digestive and gastrointestinal disorders, and two fermented preparations of RAM, designated as FRAM-1 (prepared in Luria-Bertani broth) and FRAM-2 (prepared in glucose), on intestinal epithelial cells (IECs) against LPS insult. In general, fermented formulations, especially FRAM-2, but not unfermented RAM, exerted an appreciable protective effect on IECs against LPS-induced perturbation of membrane resistance and permeability. Both fermented formulations exhibited appreciable anti-inflammatory activities in terms of their ability to inhibit LPS-induced gene expression and induced production of a number of key inflammatory mediators and cytokines in RAW 264.7 macrophage cells. However, in most cases, FRAM-2 exhibited stronger anti-inflammatory effects than FRAM-1. Our findings also suggest that suppression of nuclear factor-κβ (NF-κβ) activity might be one of the possible mechanisms by which the fermented RAM exerts its anti-inflammatory effects. Collectively, our results highlight the benefits of using fermented products of RAM to protect against LPS-induced inflammatory insult and impairment in intestinal barrier function. PMID:23573125

  15. TNFα/IFNγ Mediated Intestinal Epithelial Barrier Dysfunction Is Attenuated by MicroRNA-93 Downregulation of PTK6 in Mouse Colonic Epithelial Cells.

    PubMed

    Haines, Ricci J; Beard, Richard S; Eitner, Rebecca A; Chen, Liwei; Wu, Mack H

    2016-01-01

    transepithelial electrical resistance (TER), as well as excluded FoxO1 from the nucleus. Our results indicate that PTK6 may act as a novel mediator of intestinal epithelial permeability during inflammatory injury, and miR-93 may protect intestinal epithelial barrier function, at least in part, by targeting PTK6. PMID:27119373

  16. TNFα/IFNγ Mediated Intestinal Epithelial Barrier Dysfunction Is Attenuated by MicroRNA-93 Downregulation of PTK6 in Mouse Colonic Epithelial Cells

    PubMed Central

    Beard, Richard S.; Eitner, Rebecca A.; Chen, Liwei; Wu, Mack H.

    2016-01-01

    transepithelial electrical resistance (TER), as well as excluded FoxO1 from the nucleus. Our results indicate that PTK6 may act as a novel mediator of intestinal epithelial permeability during inflammatory injury, and miR-93 may protect intestinal epithelial barrier function, at least in part, by targeting PTK6. PMID:27119373

  17. The novel porcine Lactobacillus sobrius strain protects intestinal cells from enterotoxigenic Escherichia coli K88 infection and prevents membrane barrier damage.

    PubMed

    Roselli, Marianna; Finamore, Alberto; Britti, Maria Serena; Konstantinov, Sergey R; Smidt, Hauke; de Vos, Willem M; Mengheri, Elena

    2007-12-01

    Lactobacilli have a potential to overcome intestinal disorders; however, the exact mode of action is still largely unknown. In this study, we have used the intestinal porcine intestinal IPEC-1 epithelial cells as a model to investigate a possible protective activity of a new Lactobacillus species, the L. sobrius DSM 16698(T), against intestinal injury induced by enterotoxigenic Escherichia coli (ETEC) K88 infection and the underlying mechanisms. Treatment of infected cells with L. sobrius strongly reduced the pathogen adhesion. L. sobrius was also able to prevent the ETEC-induced membrane damage by inhibiting delocalization of zonula occludens (ZO)-1, reduction of occludin amount, rearrangement of F-actin, and dephosphorylation of occludin caused by ETEC. RT-PCR and ELISA experiments showed that L. sobrius counteracted the ETEC-induced increase of IL-8 and upregulated the IL-10 expression. The involvement of IL-8 in the deleterious effects of ETEC was proven by neutralization of IL-8 with a specific antibody. A crucial role of IL-10 was indicated by blockage of IL-10 production with neutralizing anti-IL-10 antibody that fully abrogated the L. sobrius protection. L. sobrius was also able to inhibit the internalization of ETEC, which was likely favored by the leaking barrier. The protective effects were not found with L. amylovorus DSM 20531(T) treatment, a strain derived from cattle waste but phylogenetically closely related to L. sobrius. Together, the data indicate that L. sobrius exerts protection against the harmful effects of ETEC by different mechanisms, including pathogen adhesion inhibition and maintenance of membrane barrier integrity through IL-10 regulation. PMID:18029488

  18. Impact of exogenous lipase supplementation on growth, intestinal function, mucosal immune and physical barrier, and related signaling molecules mRNA expression of young grass carp (Ctenopharyngodon idella).

    PubMed

    Liu, Sen; Feng, Lin; Jiang, Wei-Dan; Liu, Yang; Jiang, Jun; Wu, Pei; Zeng, Yun-Yun; Xu, Shu-De; Kuang, Sheng-Yao; Tang, Ling; Tang, Wu-Neng; Zhang, Yong-An; Zhou, Xiao-Qiu

    2016-08-01

    This study investigated the effects of exogenous lipase supplementation on the growth performance, intestinal growth and function, immune response and physical barrier function, and related signaling molecules mRNA expression of young grass carp (Ctenopharyngodon idella). A total of 450 grass carp (255.02 ± 0.34 g) were fed five diets for 60 days. There were 5 dietary treatments that included a normal protein and lipid diet containing 30% crude protein (CP) with 5% ether extract (EE), and the low-protein and high-lipid diets (28% CP, 6% EE) supplemented with graded levels of exogenous lipase supplementation activity at 0, 1193, 2560 and 3730 U/kg diet. The results indicated that compared with a normal protein and lipid diet (30% CP, 5% EE), a low-protein and high-lipid diet (28% CP, 6% EE) (un-supplemented lipase) improved lysozyme activities and complement component 3 contents in the distal intestine (DI), interleukin 10 mRNA expression in the proximal intestine (PI), and glutathione S-transferases activity and glutathione content in the intestine of young grass carp. In addition, in low-protein and high-lipid diets, optimal exogenous lipase supplementation significantly increased acid phosphatase (ACP) activities and complement component 3 (C3) contents (P < 0.05), up-regulated the relative mRNA levels of antimicrobial peptides (liver expressed antimicrobial peptide 2 and hepcidin) and anti-inflammatory cytokines (interleukin 10 and transforming growth factor β1) and signaling molecules inhibitor protein-κBα (IκBα) and target of rapamycin (TOR) (P < 0.05), down-regulated the mRNA levels of pro-inflammatory cytokines (tumor necrosis factor α, interleukin 8, interferon γ2, and interleukin 1β), and signaling molecules (nuclear factor kappa B p65, IκB kinase β, IκB kinase γ) (P < 0.05) in the intestine of young grass carp. Moreover, optimal exogenous lipase supplementation significantly decreased reactive oxygen species (ROS), malondialdehyde

  19. Validation of UHPLC-MS/MS methods for the determination of kaempferol and its metabolite 4-hydroxyphenyl acetic acid, and application to in vitro blood-brain barrier and intestinal drug permeability studies.

    PubMed

    Moradi-Afrapoli, Fahimeh; Oufir, Mouhssin; Walter, Fruzsina R; Deli, Maria A; Smiesko, Martin; Zabela, Volha; Butterweck, Veronika; Hamburger, Matthias

    2016-09-01

    Sedative and anxiolytic-like properties of flavonoids such as kaempferol and quercetin, and of some of their intestinal metabolites, have been demonstrated in pharmacological studies. However, routes of administration were shown to be critical for observing in vivo activity. Therefore, the ability to cross intestinal and blood-brain barriers was assessed in cell-based models for kaempferol (KMF), and for the major intestinal metabolite of KMF, 4-hydroxyphenylacetic acid (4-HPAA). Intestinal transport studies were performed with Caco-2 cells, and blood-brain barrier transport studies with an immortalized monoculture human model and a primary triple-co-culture rat model. UHPLC-MS/MS methods for KMF and 4-HPAA in Ringer-HEPES buffer and in Hank's balanced salt solution were validated according to industry guidelines. For all methods, calibration curves were fitted by least-squares quadratic regression with 1/X(2) as weighing factor, and mean coefficients of determination (R(2)) were >0.99. Data obtained with all barrier models showed high intestinal and blood-brain barrier permeation of KMF, and no permeability of 4-HPAA, when compared to barrier integrity markers. PMID:27281582

  20. The effects of fluorouracil, epirubicin, and cyclophosphamide (FEC60) on the intestinal barrier function and gut peptides in breast cancer patients: an observational study

    PubMed Central

    2013-01-01

    Background Several GI peptides linked to intestinal barrier function could be involved in the modification of intestinal permeability and the onset of diarrhea during adjuvant chemotherapy. The aim of the study was to evaluate the circulating levels of zonulin, glucagon-like peptide-2 (GLP-2), epidermal growth factor (EGF) and ghrelin and their relationship with intestinal permeability and chemotherapy induced diarrhea (CTD). Methods Sixty breast cancer patients undergoing an FEC60 regimen were enrolled, 37 patients completed the study. CTD(+) patients were discriminated by appropriate questionnaire and criteria. During chemotherapy, intestinal permeability was assessed by lactulose/mannitol urinary test on day 0 and day 14. Zonulin, GLP-2, EGF and ghrelin circulating levels were evaluated by ELISA tests at five time-points (days 0, 3, 10, 14, and 21). Results During FEC60 administration, the lactulose/mannitol ratio was significantly higher on day 14 than at baseline. Zonulin levels were not affected by chemotherapy, whereas GLP-2 and EGF levels decreased significantly. GLP-2 levels on day 14 were significantly lower than those on day 0 and day 3, while EGF values were significantly lower on day 10 than at the baseline. In contrast, the total concentrations of ghrelin increased significantly at day 3 compared to days 0 and 21, respectively. Ten patients (27%) suffered from diarrhea. On day 14 of chemotherapy, a significant increase of the La/Ma ratio occurred in CTD(+) patients compared to CTD(−) patients. With regards to circulating gut peptides, the AUCg of GLP-2 and ghrelin were significantly lower and higher in CTD(+) patients than CTD(−) ones, respectively. Finally in CTD(+) patients a significant and inverse correlation between GLP-2 and La/Ma ratio was found on day 14. Conclusions Breast cancer patients undergoing FEC60 showed alterations in the intestinal permeability, which was associated with modifications in the levels of GLP-2, ghrelin and EGF. In

  1. The serine protease-mediated increase in intestinal epithelial barrier function is dependent on occludin and requires an intact tight junction.

    PubMed

    Ronaghan, Natalie J; Shang, Judie; Iablokov, Vadim; Zaheer, Raza; Colarusso, Pina; Turner, Jerrold R; MacNaughton, Wallace K

    2016-09-01

    Barrier dysfunction is a characteristic of the inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis. Understanding how the tight junction is modified to maintain barrier function may provide avenues for treatment of IBD. We have previously shown that the apical addition of serine proteases to intestinal epithelial cell lines causes a rapid and sustained increase in transepithelial electrical resistance (TER), but the mechanisms are unknown. We hypothesized that serine proteases increase barrier function through trafficking and insertion of tight junction proteins into the membrane, and this could enhance recovery of a disrupted monolayer after calcium switch or cytokine treatment. In the canine epithelial cell line, SCBN, we showed that matriptase, an endogenous serine protease, could potently increase TER. Using detergent solubility-based cell fractionation, we found that neither trypsin nor matriptase treatment changed levels of tight junction proteins at the membrane. In a fast calcium switch assay, serine proteases did not enhance the rate of recovery of the junction. In addition, serine proteases could not reverse barrier disruption induced by IFNγ and TNFα. We knocked down occludin in our cells using siRNA and found this prevented the serine protease-induced increase in TER. Using fluorescence recovery after photobleaching (FRAP), we found serine proteases induce a greater mobile fraction of occludin in the membrane. These data suggest that a functional tight junction is needed for serine proteases to have an effect on TER, and that occludin is a crucial tight junction protein in this mechanism. PMID:27492333

  2. β-1,3/1,6-Glucan alleviated intestinal mucosal barrier impairment of broiler chickens challenged with Salmonella enterica serovar Typhimurium.

    PubMed

    Shao, Yujing; Guo, Yuming; Wang, Zhong

    2013-07-01

    This study investigated the protective effect of β-1,3/1,6-glucan on gut morphology, intestinal epithelial tight junctions, and bacterial translocation of broiler chickens challenged with Salmonella enterica serovar Typhimurium. Ninety Salmonella-free Arbor Acre male broiler chickens were randomly divided into 3 groups: negative control group (NC), Salmonella Typhimurium-infected positive group (PC), and the Salmonella Typhimurium-infected group with dietary 100 mg/kg of β-1,3/1,6-glucan supplementation (T) to determine the effect of β-1,3/1,6-glucan on intestinal barrier function. Salmonella Typhimurium challenge alone significantly decreased villus height (P < 0.001), villus height/crypt depth ratio (P < 0.05), and the number of goblet cells (P < 0.001) in the jejunum at 14 d postinfection (dpi), but significantly increased the number of intestinal secretory IgA (sIgA)-expressing cells at 14 dpi (P < 0.01) and total sIgA levels in the jejunum at 7 (P < 0.05) and 14 dpi (P < 0.01) compared with the unchallenged birds (NC). Dietary β-1,3/1,6-glucan supplementation not only significantly increased villus height, villus height/crypt depth ratio, and the number of goblet cells (P < 0.01), but also increased the number of sIgA-expressing cells (P < 0.05) and sIgA content in the jejunum at 14 dpi (P < 0.01) in birds challenged with Salmonella Typhimurium in comparison with Salmonella Typhimurium challenge alone. β-1,3/1,6-Glucan addition had significant inhibitory effects (P < 0.05) on cecal Salmonella colonization levels and liver Salmonella invasion of the Salmonella Typhimurium-infected birds compared with the PC group. Intestinal tight junction proteins claudin-1, claudin-4, and occludin mRNA expression in the jejunum at 14 dpi was significantly decreased by Salmonella Typhimurium challenge alone (P < 0.01) compared with that of the NC group, whereas β-1,3/1,6-glucan supplementation significantly increased claudin-1 and occludin mRNA expression (P < 0.01) at

  3. Characterization of tight junction disruption and immune response modulation in a miniaturized Caco-2/U937 coculture-based in vitro model of the human intestinal barrier.

    PubMed

    Ramadan, Qasem; Jing, Lin

    2016-02-01

    A microfluidic-based dynamic in vitro model of the human intestinal barrier has been constructed and characterized. The intestinal epithelial monolayer was mimicked by culturing caco-2 cells on a porous membrane in a double-layered microfluidic chip and interfaced with a co-culture of U937 as a model of immune responsive cells. The physiological flow was also mimicked by a continuous perfusion of culture media from the apical and basolateral side of the porous membrane. This dynamic "in vivo-like" environment maintains a continuous supply of cell nutrient and waste removal and create mechanical shear stress within the physiological ranges which promotes uniform cell growth and tight junction formation. The monolayer permeability to soluble ion changes after treating with LPS, and TNF α as indicated by the reduction of the TEER value. In addition, the immune competent caco-2/U937-based model allowed the investigating the role of the epithelial layer as a protection barrier to biological hazards as indicated by the suppressing of the pro-inflammatory cytokine expression. PMID:26809386

  4. Ceramide is involved in alcohol-induced neural proliferation.

    PubMed

    Wang, Zhixin; Deng, Tongxing; Deng, Jiexin; Deng, Jinbo; Gao, Xiaoqun; Shi, Yuanyuan; Liu, Bin; Ma, Zhanyou; Jin, Haixiao

    2013-08-15

    Prenatal alcohol exposure, especially during early pregnancy, can lead to fetal alcohol syndrome. The pharmacological and toxicological mechanisms of ethanol are related to the effects of ceramide. In this study, we established an alcohol exposure model in wild-type mice and in knockout mice for the key enzyme involved in ceramide metabolism, sphingomyelin synthase 2. This model received daily intragastric administration of 25% ethanol, and pups were used at postnatal days 0, 7, 14, 30 for experiments. Serology and immunofluorescence staining found that ethanol exposure dose-dependently reduced blood sphingomyelin levels in two genotypes of pups, and increased neural cell proliferation and the number of new neurons in the hippocampal dentate gyrus. Western blot analysis showed that the relative expression level of protein kinase C α increased in two notypes of pups after ethanol exposure. Compared with wild-type pups, the expression level of the important activator protein of the ceramide/ceramide-1-phosphate pathway, protein kinase C α, was reduced in the hippocampus of sphingomyelin synthase 2 knockouts. Our findings illustrate that ceramide is involved in alcohol-induced neural proliferation in the hippocampal dentate gyrus of pups after prenatal ethanol exposure, and the mechanism may be associated with increased pression of protein kinase C α activating the ceramide/ceramide-1-phosphate pathway. PMID:25206527

  5. The Molecular Circadian Clock and Alcohol-Induced Liver Injury

    PubMed Central

    Udoh, Uduak S.; Valcin, Jennifer A.; Gamble, Karen L.; Bailey, Shannon M.

    2015-01-01

    Emerging evidence from both experimental animal studies and clinical human investigations demonstrates strong connections among circadian processes, alcohol use, and alcohol-induced tissue injury. Components of the circadian clock have been shown to influence the pathophysiological effects of alcohol. Conversely, alcohol may alter the expression of circadian clock genes and the rhythmic behavioral and metabolic processes they regulate. Therefore, we propose that alcohol-mediated disruption in circadian rhythms likely underpins many adverse health effects of alcohol that cut across multiple organ systems. In this review, we provide an overview of the circadian clock mechanism and showcase results from new studies in the alcohol field implicating the circadian clock as a key target of alcohol action and toxicity in the liver. We discuss various molecular events through which alcohol may work to negatively impact circadian clock-mediated processes in the liver, and contribute to tissue pathology. Illuminating the mechanistic connections between the circadian clock and alcohol will be critical to the development of new preventative and pharmacological treatments for alcohol use disorders and alcohol-mediated organ diseases. PMID:26473939

  6. Intestinal Cell Tight Junctions Limit Invasion of Candida albicans through Active Penetration and Endocytosis in the Early Stages of the Interaction of the Fungus with the Intestinal Barrier

    PubMed Central

    Bon, Fabienne; L’Ollivier, Coralie; Laue, Michael; Holland, Gudrun; Bonnin, Alain; Dalle, Frederic

    2016-01-01

    C. albicans is a commensal yeast of the mucous membranes in healthy humans that can also cause disseminated candidiasis, mainly originating from the digestive tract, in vulnerable patients. It is necessary to understand the cellular and molecular mechanisms of the interaction of C. albicans with enterocytes to better understand the basis of commensalism and pathogenicity of the yeast and to improve the management of disseminated candidiasis. In this study, we investigated the kinetics of tight junction (TJ) formation in parallel with the invasion of C. albicans into the Caco-2 intestinal cell line. Using invasiveness assays on Caco-2 cells displaying pharmacologically altered TJ (i.e. differentiated epithelial cells treated with EGTA or patulin), we were able to demonstrate that TJ protect enterocytes against invasion of C. albicans. Moreover, treatment with a pharmacological inhibitor of endocytosis decreased invasion of the fungus into Caco-2 cells displaying altered TJ, suggesting that facilitating access of the yeast to the basolateral side of intestinal cells promotes endocytosis of C. albicans in its hyphal form. These data were supported by SEM observations of differentiated Caco-2 cells displaying altered TJ, which highlighted membrane protrusions engulfing C. albicans hyphae. We furthermore demonstrated that Als3, a hypha-specific C. albicans invasin, facilitates internalization of the fungus by active penetration and induced endocytosis by differentiated Caco-2 cells displaying altered TJ. However, our observations failed to demonstrate binding of Als3 to E-cadherin as the trigger mechanism of endocytosis of C. albicans into differentiated Caco-2 cells displaying altered TJ. PMID:26933885

  7. Pregnane X Receptor Activation Attenuates Inflammation-Associated Intestinal Epithelial Barrier Dysfunction by Inhibiting Cytokine-Induced Myosin Light-Chain Kinase Expression and c-Jun N-Terminal Kinase 1/2 Activation.

    PubMed

    Garg, Aditya; Zhao, Angela; Erickson, Sarah L; Mukherjee, Subhajit; Lau, Aik Jiang; Alston, Laurie; Chang, Thomas K H; Mani, Sridhar; Hirota, Simon A

    2016-10-01

    The inflammatory bowel diseases (IBDs) are chronic inflammatory disorders with a complex etiology. IBD is thought to arise in genetically susceptible individuals in the context of aberrant interactions with the intestinal microbiota and other environmental risk factors. Recently, the pregnane X receptor (PXR) was identified as a sensor for microbial metabolites, whose activation can regulate the intestinal epithelial barrier. Mutations in NR1I2, the gene that encodes the PXR, have been linked to IBD, and in animal models, PXR deletion leads to barrier dysfunction. In the current study, we sought to assess the mechanism(s) through which the PXR regulates barrier function during inflammation. In Caco-2 intestinal epithelial cell monolayers, tumor necrosis factor-α/interferon-γ exposure disrupted the barrier and triggered zonula occludens-1 relocalization, increased expression of myosin light-chain kinase (MLCK), and activation of c-Jun N-terminal kinase 1/2 (JNK1/2). Activation of the PXR [rifaximin and [[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethenylidene]bis-phosphonic acid tetraethyl ester (SR12813); 10 μM] protected the barrier, an effect that was associated with attenuated MLCK expression and JNK1/2 activation. In vivo, activation of the PXR [pregnenolone 16α-carbonitrile (PCN)] attenuated barrier disruption induced by toll-like receptor 4 activation in wild-type, but not Pxr-/-, mice. Furthermore, PCN treatment protected the barrier in the dextran-sulfate sodium model of experimental colitis, an effect that was associated with reduced expression of mucosal MLCK and phosphorylated JNK1/2. Together, our data suggest that the PXR regulates the intestinal epithelial barrier during inflammation by modulating cytokine-induced MLCK expression and JNK1/2 activation. Thus, targeting the PXR may prove beneficial for the treatment of inflammation-associated barrier disruption in the context of IBD. PMID:27440420

  8. Alcohol-Induced Developmental Origins of Adult-Onset Diseases.

    PubMed

    Lunde, Emilie R; Washburn, Shannon E; Golding, Michael C; Bake, Shameena; Miranda, Rajesh C; Ramadoss, Jayanth

    2016-07-01

    Fetal alcohol exposure may impair growth, development, and function of multiple organ systems and is encompassed by the term fetal alcohol spectrum disorders (FASD). Research has so far focused on the mechanisms, prevention, and diagnosis of FASD, while the risk for adult-onset chronic diseases in individuals exposed to alcohol in utero is not well explored. David Barker's hypothesis on Developmental Origins of Health and Disease (DOHaD) suggests that insults to the milieu of the developing fetus program it for adult development of chronic diseases. In the 25 years since the introduction of this hypothesis, epidemiological and animal model studies have made significant advancements in identifying in utero developmental origins of chronic adult-onset diseases affecting cardiovascular, endocrine, musculoskeletal, and psychobehavioral systems. Teratogen exposure is an established programming agent for adult diseases, and recent studies suggest that prenatal alcohol exposure correlates with adult onset of neurobehavioral deficits, cardiovascular disease, endocrine dysfunction, and nutrient homeostasis instability, warranting additional investigation of alcohol-induced DOHaD, as well as patient follow-up well into adulthood for affected individuals. In utero epigenetic alterations during critical periods of methylation are a key potential mechanism for programming and susceptibility of adult-onset chronic diseases, with imprinted genes affecting metabolism being critical targets. Additional studies in epidemiology, phenotypic characterization in response to timing, dose, and duration of exposure, as well as elucidation of mechanisms underlying FASD-DOHaD inter relation, are thus needed to clinically define chronic disease associated with prenatal alcohol exposure. These studies are critical to establish interventional strategies that decrease incidence of these adult-onset diseases and promote healthier aging among individuals affected with FASD. PMID:27254466

  9. Alcohol-induced ciliary dysfunction targets the outer dynein arm

    PubMed Central

    Yang, Fan; Pavlik, Jacqueline; Fox, Laura; Scarbrough, Chasity; Sale, Winfield S.; Sisson, Joseph H.

    2015-01-01

    Alcohol abuse results in an increased incidence of pulmonary infection, in part attributable to impaired mucociliary clearance. Analysis of motility in mammalian airway cilia has revealed that alcohol impacts the ciliary dynein motors by a mechanism involving altered axonemal protein phosphorylation. Given the highly conserved nature of cilia, it is likely that the mechanisms for alcohol-induced ciliary dysfunction (AICD) are conserved. Thus we utilized the experimental advantages offered by the model organism, Chlamydomonas, to determine the precise effects of alcohol on ciliary dynein activity and identify axonemal phosphoproteins that are altered by alcohol exposure. Analysis of live cells or reactivated cell models showed that alcohol significantly inhibits ciliary motility in Chlamydomonas via a mechanism that is part of the axonemal structure. Taking advantage of informative mutant cells, we found that alcohol impacts the activity of the outer dynein arm. Consistent with this finding, alcohol exposure results in a significant reduction in ciliary beat frequency, a parameter of ciliary movement that requires normal outer dynein arm function. Using mutants that lack specific heavy-chain motor domains, we have determined that alcohol impacts the β- and γ-heavy chains of the outer dynein arm. Furthermore, using a phospho-threonine-specific antibody, we determined that the phosphorylation state of DCC1 of the outer dynein arm-docking complex is altered in the presence of alcohol, and its phosphorylation correlates with AICD. These results demonstrate that alcohol targets specific outer dynein arm components and suggest that DCC1 is part of an alcohol-sensitive mechanism that controls outer dynein arm activity. PMID:25595647

  10. Effect of low dosage of chito-oligosaccharide supplementation on intestinal morphology, immune response, antioxidant capacity, and barrier function in weaned piglets.

    PubMed

    Xiong, X; Yang, H S; Wang, X C; Hu, Q; Liu, C X; Wu, X; Deng, D; Hou, Y Q; Nyachoti, C M; Xiao, D F; Yin, Y L

    2015-03-01

    This study was conducted to determine the effect of dietary supplementation of a low dose of chito-oligosaccharide (COS) on intestinal morphology, immune response, antioxidant capacity, and barrier function in weaned piglets. A total of 120 weaned pigs (21 d of age; 7.86 ± 0.22 kg average BW) were randomly assigned (6 pens/diet; 10 pigs/pen) to 2 dietary treatments consisting of a basal diet (negative control) or the basal diet supplemented with COS (30 mg/kg) for a 14-d period. Six randomly selected piglets from each treatment were killed for blood and tissue sampling. No significant differences were observed in ADG, ADFI, and G:F between treatment and the control group. Piglets fed the COS-supplemented diet had greater ( < 0.05) stomach pH than those fed the control diet on d 14 postweaning. Dietary supplementation with COS reduced villus height ( < 0.05) and villus height:crypt depth ( < 0.05) in the ileum. Dietary COS supplementation tended to reduce villus height in the duodenum ( = 0.065) and jejunum ( = 0.058). There was no effect on crypt depth in the intestinal segments of treatment group. Piglets fed the COS-supplemented diet increased ( < 0.05) the number of intraepithelial lymphocytes in duodenum or jejunum and goblet cells of ileum. However, COS decreased ( < 0.05) the number of intraepithelial lymphocytes in ileum of weaned piglets. The concentrations of IL-10 (duodenum, jejunum, and ileum) and secretory immunoglobulin (SIgA; duodenum and ileum) were higher in piglets fed the COS-supplemented diet compared with control ( < 0.05). Dietary COS supplementation reduced ( < 0.05) the concentration of total antioxidant capacity and superoxide dismutase of the jejunum or ileum. The mRNA expression of occludin in the ileum and ZO-1 in jejunum and ileum had a significant change in piglets fed the COS-supplemented diet compared with the control group ( < 0.05). In conclusion, these results indicated that dietary COS supplementation at 30 mg/kg had no effects

  11. Transforming growth factor-β, a whey protein component, strengthens the intestinal barrier by upregulating claudin-4 in HT-29/B6 cells.

    PubMed

    Hering, Nina A; Andres, Susanne; Fromm, Anja; van Tol, Eric A; Amasheh, Maren; Mankertz, Joachim; Fromm, Michael; Schulzke, Joerg D

    2011-05-01

    TGFβ (isoforms 1-3) has barrier-protective effects in the intestine. The mechanisms involved in regulating tight junction protein expression are poorly understood. The aim of this study was to elucidate TGFβ-dependent protective effects with special attention to promoter regulation of tight junction proteins using the HT-29/B6 cell model. In addition, the effects of whey protein concentrate 1 (WPC1), a natural source of TGFβ in human nutrition, were examined. For this purpose, the claudin-4 promoter was cloned and tested for its activity. It exhibited transactivation in response to TGFβ1, which was intensified when Smad-4 was cotransfected, indicating a Smad-4-dependent regulatory component. Shortening and mutation of the promoter altered and attenuated this effect. WPC1 induced an increase in the claudin-4 protein level and resistance of HT-29/B6 cell monolayers. Anti-TGFβ(1-3) antibodies blocked these whey protein effects, suggesting that a main part of this function was mediated through TGFβ. This effect was observed on intact monolayers as well as when barrier function was impaired by preexposure to IFNγ. In conclusion, TGFβ1 affects claudin-4 gene expression via Smad-4-dependent and -independent transcriptional regulation, resulting in barrier protection, a cytokine effect that is also found in whey protein concentrates used in enteral nutrition. PMID:21430244

  12. Influence of dietary inclusion of Bacillus licheniformis on laying performance, egg quality, antioxidant enzyme activities, and intestinal barrier function of laying hens.

    PubMed

    Lei, K; Li, Y L; Yu, D Y; Rajput, I R; Li, W F

    2013-09-01

    This experiment was conducted to evaluate the effects of dietary inclusion of Bacillus licheniformis on laying performance, egg quality, antioxidant enzyme activities, and intestinal barrier function of laying hens. Hy-Line Variety W-36 hens (n = 540; 28 wk of age) were randomized into 6 groups, each group with 6 replications (n = 15). The control group received the basal diet formulated with maize and soybean meal. The treatment groups received the same basal diets supplemented with 0.01, 0.02, 0.03, 0.06, and 0.09% Bacillus licheniformis powder (2 × 10(10) cfu/g) for an 8-wk trial. The results showed that dietary supplementation with 0.01 and 0.03% B. licheniformis significantly increased egg production and egg mass. However, no significant differences were observed in egg weight, feed consumption, and feed conversion efficiency among the 6 groups. Supplementation with different levels of B. licheniformis was found to be effective in improvement of egg quality by increasing egg shell thickness and strength. Compared with control, d-lactate content, diamine oxidase activity, and adrenocorticotropic hormone level in serum decreased significantly, and the level of estradiol and follicle-stimulating hormone increased significantly in plasma of all the experimental groups. Dietary supplementation with B. licheniformis increased the intestinal villus height and reduced the crypt depth. In conclusion, dietary inclusion of B. licheniformis could improve laying performance and egg quality significantly in a dose-dependent manner by decreasing the stress response, upregulating the growth hormone, and improving intestinal health. PMID:23960122

  13. Intestinal Cell Barrier Function In Vitro Is Severely Compromised by Keratin 8 and 18 Mutations Identified in Patients with Inflammatory Bowel Disease

    PubMed Central

    Zupancic, Tina; Stojan, Jure; Lane, Ellen Birgitte; Komel, Radovan; Bedina-Zavec, Apolonija; Liovic, Mirjana

    2014-01-01

    Keratin 8 and 18 (K8/K18) mutations have been implicated in the aetiology of certain pathogenic processes of the liver and pancreas. While some K8 mutations (K8 G62C, K8 K464N) are also presumed susceptibility factors for inflammatory bowel disease (IBD), the only K18 mutation (K18 S230T) discovered so far in an IBD patient is thought to be a polymorphism. The aim of our study was to demonstrate that these mutations might also directly affect intestinal cell barrier function. Cell monolayers of genetically engineered human colonocytes expressing these mutations were tested for permeability, growth rate and resistance to heat-stress. We also calculated the change in dissociation constant (Kd, measure of affinity) each of these mutations introduces into the keratin protein, and present the first model of a keratin dimer L12 region with in silico clues to how the K18 S230T mutation may affect keratin function. Physiologically, these mutations cause up to 30% increase in paracellular permeability in vitro. Heat-stress induces little keratin clumping but instead cell monolayers peel off the surface suggesting a problem with cell junctions. K18 S230T has pronounced pathological effects in vitro marked by high Kd, low growth rate and increased permeability. The latter may be due to the altered distribution of tight junction components claudin-4 and ZO-1. This is the first time intestinal cells have been suggested also functionally impaired by K8/K18 mutations. Although an in vitro colonocyte model system does not completely mimic the epithelial lining of the intestine, nevertheless the data suggest that K8/K18 mutations may be also able to produce a phenotype in vivo. PMID:24915158

  14. Bacterial translocation and in vivo assessment of intestinal barrier permeability in rainbow trout (Oncorhynchus mykiss) with and without soyabean meal-induced inflammation.

    PubMed

    Mosberian-Tanha, Peyman; Øverland, Margareth; Landsverk, Thor; Reveco, Felipe E; Schrama, Johan W; Roem, Andries J; Agger, Jane W; Mydland, Liv T

    2016-01-01

    The primary aim of this experiment was to evaluate the intestinal barrier permeability in vivo in rainbow trout (Oncorhynchus mykiss) fed increasing levels of soyabean meal (SBM). The relationship between SBM-induced enteritis (SBMIE) and the permeability markers was also investigated. Our results showed that the mean score of morphological parameters was significantly higher as a result of 37·5 % SBM inclusion in the diet, while the scores of fish fed 25 % SBM or lower were not different from those of the fish meal-fed controls (P < 0·05). SBMIE was found in the distal intestine (DI) in 18 % of the fish (eleven of sixty): ten in the 37·5 % SBM-fed group and one in the 25 % SBM-fed group. Sugar markers in plasma showed large variation among individuals probably due to variation in feed intake. We found, however, a significant linear increase in the level of plasma d-lactate with increasing SBM inclusion level (P < 0·0001). Plasma concentration of endotoxin was not significantly different in groups with or without SBMIE. Some individual fish showed high values of endotoxin in blood, but the same individuals did not show any bacterial translocation. Plasma bacterial DNA was detected in 28 % of the fish with SBMIE, and 8 % of non-SBMIE fish (P = 0·07). Plasma concentration of d-lactate was significantly higher in fish with SBMIE (P < 0·0001). To conclude, SBMIE in the DI of rainbow trout was associated with an increase in bacterial translocation and plasma d-lactate concentration, suggesting that these permeability markers can be used to evaluate intestinal permeability in vivo. PMID:27547389

  15. Early Activation of MAPK p44/42 Is Partially Involved in DON-Induced Disruption of the Intestinal Barrier Function and Tight Junction Network.

    PubMed

    Springler, Alexandra; Hessenberger, Sabine; Schatzmayr, Gerd; Mayer, Elisabeth

    2016-01-01

    Deoxynivalenol (DON), produced by the plant pathogens Fusarium graminearum and Fusarium culmorum, is one of the most common mycotoxins, contaminating cereal and cereal-derived products. Although worldwide contamination of food and feed poses health threats to humans and animals, pigs are particularly susceptible to this mycotoxin. DON derivatives, such as deepoxy-deoxynivalenol (DOM-1), are produced by bacterial transformation of certain intestinal bacteria, which are naturally occurring or applied as feed additives. Intestinal epithelial cells are the initial barrier against these food- and feed-borne toxins. The present study confirms DON-induced activation of MAPK p44/42 and inhibition of p44/42 by MAPK-inhibitor U0126 monoethanolate. Influence of DON and DOM-1 on transepithelial electrical resistance (TEER), viability and expression of seven tight junction proteins (TJ), as well as the potential of U0126 to counteract DON-induced effects, was assessed. While DOM-1 showed no effect, DON significantly reduced TEER of differentiated IPEC-J2 and decreased expression of claudin-1 and -3, while leaving claudin-4; ZO-1, -2, and -3 and occludin unaffected. Inhibition of p44/42 counteracted DON-induced TEER decrease and restored claudin-3, but not claudin-1 expression. Therefore, effects of DON on TEER and claudin-3 are at least partially p44/42 mediated, while effects on viability and claudin-1 are likely mediated via alternative pathways. PMID:27618100

  16. Effects of early enteral nutrition on the gastrointestinal motility and intestinal mucosal barrier of patients with burn-induced invasive fungal infection

    PubMed Central

    Zhang, Yu; Gu, Fang; Wang, Fengxian; Zhang, Yuanda

    2016-01-01

    Objective: To evaluate the effects of early enteral nutrition on the gastrointestinal motility and intestinal mucosal barrier of patients with burn-induced invasive fungal infection. Methods: A total of 120 patients with burn-induced invasive fungal infection were randomly divided into an early enteral nutrition (EN) group and a parenteral nutrition (PN) group (n=60). The patients were given nutritional support intervention for 14 days, and the expression levels of serum transferrin, albumin, total protein, endotoxin, D-lactic acid and inflammatory cytokines were detected on the 1st, 7th and 14th days respectively. Results: As the treatment progressed, the levels of serum transferrin, albumin and total protein of the EN group were significantly higher than those of the PN group (P<0.05), while the levels of serum endotoxin and D-lactic acid of the form group were significantly lower (P<0.05). After treatment, the expression levels of IL-6 and TNF-α were decreased in the EN group, which were significantly different from those of the PN group (P<0.05). During treatment, the incidence rates of complications such as abdominal distension, diarrhea, sepsis, nausea, vomiting and gastric retention were similar. The mean healing time of wound surface was 9.34±0.78 days in the EN group and 12.46±2.19 days in the PN group, i.e. such time of the former was significantly shorter than that of the latter (P<0.05). Conclusion: Treating patients having burn-induced invasive fungal infection by early enteral nutrition support with arginine can safely alleviate malnutrition and stress reaction, strengthen cellular immune function and promote wound healing, thereby facilitating the recovery of gastrointestinal motility and the function of intestinal mucosal barrier. PMID:27375697

  17. A Gut Microbial Metabolite of Linoleic Acid, 10-Hydroxy-cis-12-octadecenoic Acid, Ameliorates Intestinal Epithelial Barrier Impairment Partially via GPR40-MEK-ERK Pathway*

    PubMed Central

    Miyamoto, Junki; Mizukure, Taichi; Park, Si-Bum; Kishino, Shigenobu; Kimura, Ikuo; Hirano, Kanako; Bergamo, Paolo; Rossi, Mauro; Suzuki, Takuya; Arita, Makoto; Ogawa, Jun; Tanabe, Soichi

    2015-01-01

    Gut microbial metabolites of polyunsaturated fatty acids have attracted much attention because of their various physiological properties. Dysfunction of tight junction (TJ) in the intestine contributes to the pathogenesis of many disorders such as inflammatory bowel disease. We evaluated the effects of five novel gut microbial metabolites on tumor necrosis factor (TNF)-α-induced barrier impairment in Caco-2 cells and dextran sulfate sodium-induced colitis in mice. 10-Hydroxy-cis-12-octadecenoic acid (HYA), a gut microbial metabolite of linoleic acid, suppressed TNF-α and dextran sulfate sodium-induced changes in the expression of TJ-related molecules, occludin, zonula occludens-1, and myosin light chain kinase. HYA also suppressed the expression of TNF receptor 2 (TNFR2) mRNA and protein expression in Caco-2 cells and colonic tissue. In addition, HYA suppressed the protein expression of TNFR2 in murine intestinal epithelial cells. Furthermore, HYA significantly up-regulated G protein-coupled receptor (GPR) 40 expression in Caco-2 cells. It also induced [Ca2+]i responses in HEK293 cells expressing human GPR40 with higher sensitivity than linoleic acid, its metabolic precursor. The barrier-recovering effects of HYA were abrogated by a GPR40 antagonist and MEK inhibitor in Caco-2 cells. Conversely, 10-hydroxyoctadacanoic acid, which is a gut microbial metabolite of oleic acid and lacks a carbon-carbon double bond at Δ12 position, did not show these TJ-restoring activities and down-regulated GPR40 expression. Therefore, HYA modulates TNFR2 expression, at least partially, via the GPR40-MEK-ERK pathway and may be useful in the treatment of TJ-related disorders such as inflammatory bowel disease. PMID:25505251

  18. Dietary cholesterol protects against alcohol-induced cerebral artery constriction

    PubMed Central

    Bukiya, Anna; Dopico, Alex; Leffler, Charles; Fedinec, Alexander

    2014-01-01

    Background Binge drinking represents the major form of excessive alcohol (EtOH) consumption in the US. Episodic (such as binge) drinking results in blood alcohol levels (BAL) of 18–80 mM, and leads to alcohol-induced cerebral artery constriction (AICAC). AICAC was shown to arise from EtOH-induced inhibition of large-conductance, calcium/voltage-gated potassium (BK) channels in the vascular smooth muscle. Factors that modulate BK channel-mediated AICAC remain largely unknown. Methods Male Sprague-Dawley rats were placed on high-cholesterol (2% of cholesterol) diet for 18–23 weeks. Their littermates were placed on control iso-caloric diet. AICAC was evaluated both in vivo and in vitro, by means of pial arteriole diameter monitoring through a closed cranial window and diameter measurements of isolated, pressurized cerebral arteries. Cholesterol level in the cerebral artery tissue was manipulated by methyl-β-cyclodextrin to reverse dietary-induced accumulation of cholesterol. BK channel surface presence on the plasma membrane of cerebral artery myocytes was evaluated by immunofluorescence staining. BK channel function in pressurized cerebral artery was assessed using selective BK channel blocker paxilline. Results Within 5 minutes of 50 mM EtOH injection into carotid artery in vivo, arteriole diameter decreased by 20% in control group. Pial arteriole constriction was significantly reduced in rats on high-cholesterol diet, resulting in only 10% reduction of diameter. BAL in both groups, however, remained the same. Significant reduction of AICAC in group on high-cholesterol diet compared to control was also observed after middle cerebral artery dissection and in vitro pressurization at 60 mmHg, this reduction remaining after endothelium removal. Cholesterol level in de-endothelialized cerebral arteries was significantly increased in rats on high-cholesterol diet. Removal of excessive cholesterol content restored AICAC to the level, observed in cerebral arteries of

  19. Crosstalk between Microbiota-Derived Short-Chain Fatty Acids and Intestinal Epithelial HIF Augments Tissue Barrier Function.

    PubMed

    Kelly, Caleb J; Zheng, Leon; Campbell, Eric L; Saeedi, Bejan; Scholz, Carsten C; Bayless, Amanda J; Wilson, Kelly E; Glover, Louise E; Kominsky, Douglas J; Magnuson, Aaron; Weir, Tiffany L; Ehrentraut, Stefan F; Pickel, Christina; Kuhn, Kristine A; Lanis, Jordi M; Nguyen, Vu; Taylor, Cormac T; Colgan, Sean P

    2015-05-13

    Interactions between the microbiota and distal gut are fundamental determinants of human health. Such interactions are concentrated at the colonic mucosa and provide energy for the host epithelium through the production of the short-chain fatty acid butyrate. We sought to determine the role of epithelial butyrate metabolism in establishing the austere oxygenation profile of the distal gut. Bacteria-derived butyrate affects epithelial O2 consumption and results in stabilization of hypoxia-inducible factor (HIF), a transcription factor coordinating barrier protection. Antibiotic-mediated depletion of the microbiota reduces colonic butyrate and HIF expression, both of which are restored by butyrate supplementation. Additionally, germ-free mice exhibit diminished retention of O2-sensitive dyes and decreased stabilized HIF. Furthermore, the influences of butyrate are lost in cells lacking HIF, thus linking butyrate metabolism to stabilized HIF and barrier function. This work highlights a mechanism where host-microbe interactions augment barrier function in the distal gut. PMID:25865369

  20. Intestinal REG3 Lectins Protect against Alcoholic Steatohepatitis by Reducing Mucosa-Associated Microbiota and Preventing Bacterial Translocation.

    PubMed

    Wang, Lirui; Fouts, Derrick E; Stärkel, Peter; Hartmann, Phillipp; Chen, Peng; Llorente, Cristina; DePew, Jessica; Moncera, Kelvin; Ho, Samuel B; Brenner, David A; Hooper, Lora V; Schnabl, Bernd

    2016-02-10

    Approximately half of all deaths from liver cirrhosis, the tenth leading cause of mortality in the United States, are related to alcohol use. Chronic alcohol consumption is accompanied by intestinal dysbiosis and bacterial overgrowth, yet little is known about the factors that alter the microbial composition or their contribution to liver disease. We previously associated chronic alcohol consumption with lower intestinal levels of the antimicrobial-regenerating islet-derived (REG)-3 lectins. Here, we demonstrate that intestinal deficiency in REG3B or REG3G increases numbers of mucosa-associated bacteria and enhances bacterial translocation to the mesenteric lymph nodes and liver, promoting the progression of ethanol-induced fatty liver disease toward steatohepatitis. Overexpression of Reg3g in intestinal epithelial cells restricts bacterial colonization of mucosal surfaces, reduces bacterial translocation, and protects mice from alcohol-induced steatohepatitis. Thus, alcohol appears to impair control of the mucosa-associated microbiota, and subsequent breach of the mucosal barrier facilitates progression of alcoholic liver disease. PMID:26867181

  1. Influence of thermally-oxidized vegetable oils and animal fats on intestinal barrier function and immune variables in young pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the effect of feeding thermally-oxidized lipids on metabolic oxidative status, gut barrier function, and immune response of young pigs, 108 barrows (6.67 ± 0.03 kg BW) were assigned to 12 dietary treatments in a 4 × 3 factorial design in addition to a corn-soybean meal control diet. Main...

  2. Remodeling of Tight Junctions and Enhancement of Barrier Integrity of the CACO-2 Intestinal Epithelial Cell Layer by Micronutrients

    PubMed Central

    Valenzano, Mary Carmen; DiGuilio, Katherine; Mercado, Joanna; Teter, Mimi; To, Julie; Ferraro, Brendan; Mixson, Brittany; Manley, Isabel; Baker, Valerissa; Moore, Beverley A.; Wertheimer, Joshua; Mullin, James M.

    2015-01-01

    The micronutrients zinc, quercetin, butyrate, indole and berberine were evaluated for their ability to induce remodeling of epithelial tight junctions (TJs) and enhance barrier integrity in the CACO-2 gastrointestinal epithelial cell culture model. All five of these chemically very diverse micronutrients increased transepithelial electrical resistance (Rt) significantly, but only berberine also improved barrier integrity to the non-electrolyte D-mannitol. Increases of Rt as much as 200% of untreated controls were observed. Each of the five micronutrients also induced unique, signature-like changes in TJ protein composition, suggesting multiple pathways (and TJ arrangements) by which TJ barrier function can be enhanced. Decreases in abundance by as much as 90% were observed for claudin-2, and increases of over 300% could be seen for claudins -5 and -7. The exact effects of the micronutrients on barrier integrity and TJ protein composition were found to be highly dependent on the degree of differentiation of the cell layer at the time it was exposed to the micronutrient. The substratum to which the epithelial layer adheres was also found to regulate the response of the cell layer to the micronutrient. The implications of these findings for therapeutically decreasing morbidity in Inflammatory Bowel Disease are discussed. PMID:26226276

  3. Prions efficiently cross the intestinal barrier after oral administration: Study of the bioavailability, and cellular and tissue distribution in vivo

    PubMed Central

    Urayama, Akihiko; Concha-Marambio, Luis; Khan, Uffaf; Bravo-Alegria, Javiera; Kharat, Vineetkumar; Soto, Claudio

    2016-01-01

    Natural forms of prion diseases frequently originate by oral (p.o.) infection. However, quantitative information on the gastro-intestinal (GI) absorption of prions (i.e. the bioavailability and subsequent biodistribution) is mostly unknown. The main goal of this study was to evaluate the fate of prions after oral administration, using highly purified radiolabeled PrPSc. The results showed a bi-phasic reduction of PrPSc with time in the GI, except for the ileum and colon which showed sustained increases peaking at 3–6 hr, respectively. Plasma and whole blood 125I-PrPSc reached maximal levels by 30 min and 3 hr, respectively, and blood levels were constantly higher than plasma. Upon crossing the GI-tract 125I-PrPSc became associated to blood cells, suggesting that binding to cells decreased the biological clearance of the agent. Size-exclusion chromatography revealed that oligomeric 125I-PrPSc were transported from the intestinal tract, and protein misfolding cyclic amplification showed that PrPSc in organs and blood retained the typical prion self-replicating ability. Pharmacokinetic analysis found the oral bioavailability of 125I-PrPSc to be 33.6%. Interestingly, 125I-PrPSc reached the brain in a quantity equivalent to the minimum amount needed to initiate prion disease. Our findings provide a comprehensive and quantitative study of the fate of prions upon oral infection. PMID:27573341

  4. Investigation of the effect of the uneven distribution of CYP3A4 and P-glycoprotein in the intestine on the barrier function against xenobiotics: a simulation study.

    PubMed

    Watanabe, Takao; Maeda, Kazuya; Nakai, Chikako; Sugiyama, Yuichi

    2013-09-01

    CYP3A4 and P-glycoprotein (P-gp) have similar substrate specificities and work together to form an intestinal absorption barrier against xenobiotics. Previous reports have indicated that CYP3A4 expression decreases gradually, whereas P-gp expression increases, from the upper to lower small intestine. The physiological rationale for this uneven distribution of CYP3A4 and P-gp as a barrier against xenobiotics has not been determined. To clarify the effect of these distribution patterns on barrier function, we constructed a mathematical model that included passive membrane permeation, P-gp-mediated apical efflux, and CYP3A4-mediated metabolism, and we simulated the effects of these distribution patterns on the fraction absorbed of co-substrates without changing their overall activities. The simulation showed that the physiological distribution patterns of both CYP3A4 and P-gp result in the lowest fraction absorbed, but not for drugs with low CYP3A4 and high P-gp-mediated clearances. These results suggest that the distribution pattern of CYP3A4 is especially important for the barrier function. On the other hand, physiological distribution pattern of P-gp exerts the maximum barrier function for dual good substrates for P-gp and CYP3A4, but even distribution of P-gp mostly suppresses the intestinal absorption of good P-gp, but poor CYP3A4 substrates. PMID:23754337

  5. Prions efficiently cross the intestinal barrier after oral administration: Study of the bioavailability, and cellular and tissue distribution in vivo.

    PubMed

    Urayama, Akihiko; Concha-Marambio, Luis; Khan, Uffaf; Bravo-Alegria, Javiera; Kharat, Vineetkumar; Soto, Claudio

    2016-01-01

    Natural forms of prion diseases frequently originate by oral (p.o.) infection. However, quantitative information on the gastro-intestinal (GI) absorption of prions (i.e. the bioavailability and subsequent biodistribution) is mostly unknown. The main goal of this study was to evaluate the fate of prions after oral administration, using highly purified radiolabeled PrP(Sc). The results showed a bi-phasic reduction of PrP(Sc) with time in the GI, except for the ileum and colon which showed sustained increases peaking at 3-6 hr, respectively. Plasma and whole blood (125)I-PrP(Sc) reached maximal levels by 30 min and 3 hr, respectively, and blood levels were constantly higher than plasma. Upon crossing the GI-tract (125)I-PrP(Sc) became associated to blood cells, suggesting that binding to cells decreased the biological clearance of the agent. Size-exclusion chromatography revealed that oligomeric (125)I-PrP(Sc) were transported from the intestinal tract, and protein misfolding cyclic amplification showed that PrP(Sc) in organs and blood retained the typical prion self-replicating ability. Pharmacokinetic analysis found the oral bioavailability of (125)I-PrP(Sc) to be 33.6%. Interestingly, (125)I-PrP(Sc) reached the brain in a quantity equivalent to the minimum amount needed to initiate prion disease. Our findings provide a comprehensive and quantitative study of the fate of prions upon oral infection. PMID:27573341

  6. Toxic Effects of Maternal Zearalenone Exposure on Intestinal Oxidative Stress, Barrier Function, Immunological and Morphological Changes in Rats

    PubMed Central

    Liu, Min; Gao, Rui; Meng, Qingwei; Zhang, Yuanyuan; Bi, Chongpeng; Shan, Anshan

    2014-01-01

    The present study was conducted to investigate the effects of maternal zearalenone (ZEN) exposure on the intestine of pregnant Sprague-Dawley (SD) rats and its offspring. Ninety-six pregnant SD rats were randomly divided into four groups and were fed with diets containing ZEN at concentrations of 0.3 mg/kg, 48.5 mg/kg, 97.6 mg/kg or 146.0 mg/kg from gestation days (GD) 1 to 7. All rats were fed with mycotoxin-free diet until their offspring were weaned at three weeks of age. The small intestinal fragments from pregnant rats at GD8, weaned dams and pups were collected and studied for toxic effects of ZEN on antioxidant status, immune response, expression of junction proteins, and morphology. The results showed that ZEN induced oxidative stress, affected the villous structure and reduced the expression of junction proteins claudin-4, occludin and connexin43 (Cx43) in a dose-dependent manner in pregnant rats. Different effects on the expression of cytokines were also observed both in mRNA and protein levels in these pregnant groups. Ingestion of high levels of ZEN caused irreversible damage in weaned dams, such as oxidative stress, decreased villi hight and low expression of junction proteins and cytokines. Decreased expression of jejunal interleukin-8 (IL-8) and increased expression of gastrointestinal glutathione peroxidase (GPx2) mRNA were detected in weaned offspring, indicating long-term damage caused by maternal ZEN. We also found that the Nrf2 expression both in mRNA and protein levels were up-regulated in the ZEN-treated groups of pregnant dams and the high-dose of ZEN group of weaned dams. The data indicate that modulation of Nrf2-mediated pathway is one of mechanism via which ZEN affects gut wall antioxidant and inflammatory responses. PMID:25180673

  7. Autophagy in Alcohol-Induced Multiorgan Injury: Mechanisms and Potential Therapeutic Targets

    PubMed Central

    Wang, Shaogui; Ni, Hong-Min; Huang, Heqing

    2014-01-01

    Autophagy is a genetically programmed, evolutionarily conserved intracellular degradation pathway involved in the trafficking of long-lived proteins and cellular organelles to the lysosome for degradation to maintain cellular homeostasis. Alcohol consumption leads to injury in various tissues and organs including liver, pancreas, heart, brain, and muscle. Emerging evidence suggests that autophagy is involved in alcohol-induced tissue injury. Autophagy serves as a cellular protective mechanism against alcohol-induced tissue injury in most tissues but could be detrimental in heart and muscle. This review summarizes current knowledge about the role of autophagy in alcohol-induced injury in different tissues/organs and its potential molecular mechanisms as well as possible therapeutic targets based on modulation of autophagy. PMID:25140315

  8. Alcohol-induced respiratory symptoms are common in patients with aspirin exacerbated respiratory disease

    PubMed Central

    Cardet, Juan Carlos; White, Andrew A.; Barrett, Nora A.; Feldweg, Anna M.; Wickner, Paige G.; Savage, Jessica; Bhattacharyya, Neil; Laidlaw, Tanya M.

    2014-01-01

    Background A large percentage of patients with aspirin exacerbated respiratory disease (AERD) report the development of alcohol-induced respiratory reactions, but the true prevalence of respiratory reactions caused by alcoholic beverages in these patients was not known. Objective We sought to evaluate the incidence and characteristics of alcohol-induced respiratory reactions in patients with AERD. Methods A questionnaire designed to assess alcohol-induced respiratory symptoms was administered to patients at Brigham and Women’s Hospital and Scripps Clinic. At least 50 patients were recruited into each of four clinical groups: 1) patients with aspirin challenge-confirmed AERD, 2) aspirin-tolerant asthmatics (ATA), 3) aspirin-tolerant patients with chronic rhinosinusitis (CRS), and 4) healthy controls. Two-tailed Fisher’s exact test with Bonferroni corrections were used to compare the prevalence of respiratory symptoms between AERD and other groups, with P≤0.017 considered significant. Results The prevalence of alcohol-induced upper (rhinorrhea/nasal congestion) respiratory reactions in patients with AERD was 75%, compared to 33% in ATA, 30% in CRS, and 14% in healthy controls (P<0.001 for all comparisons). The prevalence of alcohol-induced lower (wheezing/dyspnea) respiratory reactions in AERD was 51%, compared to 20% in ATA, and 0% in both CRS and healthy controls (P<0.001 for all comparisons). These reactions were generally not specific to one type of alcohol and often occurred after ingestion of only a few sips of alcohol. Conclusion Alcohol ingestion causes respiratory reactions in the majority of patients with AERD and clinicians should be aware that these alcohol-induced reactions are significantly more common in AERD than in aspirin-tolerant controls. PMID:24607050

  9. Diosmectite-zinc oxide composite improves intestinal barrier restoration and modulates TGF-β1, ERK1/2, and Akt in piglets after acetic acid challenge.

    PubMed

    Song, Z-H; Ke, Y-L; Xiao, K; Jiao, L-F; Hong, Q-H; Hu, C-H

    2015-04-01

    The present study evaluated the beneficial effect of diosmectite-zinc oxide composite (DS-ZnO) on improving intestinal barrier restoration in piglets after acetic acid challenge and explored the underlying mechanisms. Twenty-four 35-d-old piglets (Duroc × Landrace × Yorkshire), with an average weight of 8.1 kg, were allocated to 4 treatment groups. On d 1 of the trial, colitis was induced via intrarectal injection of acetic acid (10 mL of 10% acetic acid [ACA] solution for ACA, DS-ZnO, and mixture of diosmectite [DS] and ZnO [DS+ZnO] groups) and the control group was infused with saline. Twenty-four hours after challenged, piglets were fed with the following diets: 1) control group (basal diet), 2) ACA group (basal diet), 3) DS-ZnO group (basal diet supplemented with DS-ZnO), and 4) DS+ZnO group (mixture of 1.5 g diosmectite [DS]/kg and 500 mg Zn/kg from ZnO [equal amount of DS and ZnO in the DS-ZnO treatment group]). On d 8 of the trial, piglets were sacrificed. The results showed that DS-ZnO supplementation improved (P < 0.05) ADG, ADFI, and transepithelial electrical resistance and decreased (P < 0.05) fecal scores, crypt depth, and fluorescein isothiocyanate-dextran 4 kDa (FD4) influx as compared with ACA group. Moreover, DS-ZnO increased (P < 0.05) occludin, claudin-1, and zonula occluden-1 expressions; reduced (P < 0.05) caspase-9 and caspase-3 activity and Bax expression; and improved (P < 0.05) Bcl2, XIAP, and PCNA expression. Diosmectite-zinc oxide composite supplementation also increased (P < 0.05) TGF-β1 expression and ERK1/2 and Akt activation. These results suggest that DS-ZnO attenuates the acetic acid-induced colitis by improving mucosa barrier restoration, inhibiting apoptosis, and improving intestinal epithelial cells proliferation and modulation of TGF-β1 and ERK1/2 and Akt signaling pathway. PMID:26020182

  10. Metformin protects against the development of fructose-induced steatosis in mice: role of the intestinal barrier function.

    PubMed

    Spruss, Astrid; Kanuri, Giridhar; Stahl, Carolin; Bischoff, Stephan C; Bergheim, Ina

    2012-07-01

    To test the hypothesis that metformin protects against fructose-induced steatosis, and if so, to elucidate underlying mechanisms, C57BL/6J mice were either fed 30% fructose solution or plain water for 8 weeks. Some of the animals were concomitantly treated with metformin (300 mg/kg body weight/day) in the drinking solution. While chronic consumption of 30% fructose solution caused a significant increase in hepatic triglyceride accumulation and plasma alanine-aminotransferase levels, this effect of fructose was markedly attenuated in fructose-fed mice concomitantly treatment with metformin. The protective effects of the metformin treatment on the onset of fructose-induced non-alcoholic fatty liver disease (NAFLD) were associated with a protection against the loss of the tight junction proteins occludin and zonula occludens 1 in the duodenum of fructose-fed mice and the increased translocation of bacterial endotoxin found in mice only fed with fructose. In line with these findings, in metformin-treated fructose-fed animals, hepatic expression of genes of the toll-like receptor-4-dependent signalling cascade as well as the plasminogen-activator inhibitor/cMet-regulated lipid export were almost at the level of controls. Taken together, these data suggest that metformin not only protects the liver from the onset of fructose-induced NAFLD through mechanisms involving its direct effects on hepatic insulin signalling but rather through altering intestinal permeability and subsequently the endotoxin-dependent activation of hepatic Kupffer cells. PMID:22525431

  11. [Intestinal-brain axis. Neuronal and immune-inflammatory mechanisms of brain and intestine pathology].

    PubMed

    Bondarenko, V M; Riabichenko, E V

    2013-01-01

    Mutually directed connections between intestine and brain are implemented by endocrine, neural and immune systems and nonspecific natural immunity. Intestine micro flora as an active participant of intestine-brain axis not only influences intestine functions but also stimulates the development of CNS in perinatal period and interacts with higher nervous centers causing depression and cognitive disorders in pathology. A special role belongs to intestine microglia. Apart from mechanic (protective) and trophic functions for intestine neurons, glia implements neurotransmitter, immunologic, barrier and motoric functions in the intestine. An interconnection between intestine barrier function and hematoencephalic barrier regulation exists. Chronic endotoxinemia as a result of intestine barrier dysfunction forms sustained inflammation state in periventricular zone of the brain with consequent destabilization of hematoencephalic barriers and spread oF inflammation to other parts of the brain resulting in neurodegradation development. PMID:23805681

  12. Purple potato (Solanum tuberosum L.) anthocyanins attenuate alcohol-induced hepatic injury by enhancing antioxidant defense.

    PubMed

    Jiang, Zhihui; Chen, Chen; Wang, Jian; Xie, Wenyan; Wang, Meng; Li, Xinsheng; Zhang, Xiaoying

    2016-01-01

    Alcoholic liver disease (ALD) is a serious and challenging health issue. In the past decade, natural components possessing hepatoprotective properties have gained more attention for ALD intervention. In this study, the phytochemical components of anthocyanins from purple potato were assessed using UPLC-MS/MS, and the hepatoprotective effects of purple potato anthocyanins (PPAs) were investigated in the ALD mouse model. Serum and liver biochemical parameters were determined, along with histopathological changes in liver tissue. In addition, the major contributors to alcohol-induced oxidative stress were assessed. The results indicated that the levels of aspartate transaminase and alanine transaminase were lower in the serum of the PPA-treated group than the alcohol-treated group. PPAs significantly inhibited the reduction of total cholesterol and triglycerides. Higher levels of superoxide dismutase and reduced glutathione enzymes as well as a reduction in the formation of malondialdehyde occurred in mice fed with PPAs. In addition, PPAs protected against increased alcohol-induced levels and activity of cytochrome P450 2E1 (CYP2E1), which demonstrates the effects of PPAs against alcohol-induced oxidative stress and liver injury. This study suggests that PPAs could be an effective therapeutic agent in alcohol-induced liver injuries by inhibiting CYP2E1 expression and thereby strengthening antioxidant defenses. PMID:26481011

  13. Maltol, a Food Flavoring Agent, Attenuates Acute Alcohol-Induced Oxidative Damage in Mice

    PubMed Central

    Han, Ye; Xu, Qi; Hu, Jiang-ning; Han, Xin-yue; Li, Wei; Zhao, Li-chun

    2015-01-01

    The purpose of this study was to evaluate the hepatoprotective effect of maltol, a food-flavoring agent, on alcohol-induced acute oxidative damage in mice. Maltol used in this study was isolated from red ginseng (Panax ginseng C.A Meyer) and analyzed by high performance liquid chromatography (HPLC) and mass spectrometry. For hepatoprotective activity in vivo, pretreatment with maltol (12.5, 25 and 50 mg/kg; 15 days) drastically prevented the elevated activities of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and triglyceride (TG) in serum and the levels of malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) in liver tissue (p < 0.05). Meanwhile, the levels of hepatic antioxidant, such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) were elevated by maltol pretreatment, compared to the alcohol group (p < 0.05). Histopathological examination revealed that maltol pretreatment significantly inhibited alcohol-induced hepatocyte apoptosis and fatty degeneration. Interestingly, pretreatment of maltol effectively relieved alcohol-induced oxidative damage in a dose-dependent manner. Maltol appeared to possess promising anti-oxidative and anti-inflammatory capacities. It was suggested that the hepatoprotective effect exhibited by maltol on alcohol-induced liver oxidative injury may be due to its potent antioxidant properties. PMID:25608939

  14. Protective effect of oligomeric proanthocyanidins against alcohol-induced liver steatosis and injury in mice.

    PubMed

    Wang, Zhiguo; Su, Bo; Fan, Sumei; Fei, Haixia; Zhao, Wei

    2015-03-20

    The long-term consumption of alcohol has been associated with multiple pathologies at all levels, such as alcoholism, chronic pancreatitis, malnutrition, alcoholic liver disease (ALD) and cancer. In the current study, we investigated the protective effect of oligomeric proanthocyanidins (OPC) against alcohol-induced liver steatosis and injury and the possible mechanisms using ethanol-induced chronic liver damage mouse models. The results showed that OPC significantly improved alcohol-induced dyslipidemia and alleviated liver steatosis by reducing levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total triglyceride (TG), total cholesterol (TC), low-density cholesterol (LDL-c) and liver malondialdehyde (MDA), and increasing levels of serum high-density lipoprotein (HDL-c), liver superoxide dismutase (SOD). Further investigation indicated that OPC markedly decreased the expressions of lipid synthesis genes and inflammation genes such as sterol regulatory element-binding protein-1c (Srebp-1c), protein-2 (Srebp2), interleukin IL-1β, IL-6 and TNF-α. Furthermore, AML-12 cells line was used to investigate the possible mechanisms which indicated that OPC might alleviate liver steatosis and damage through AMP-activated protein kinase (AMPK) activation involving oxidative stress. In conclusion, our study demonstrated excellent protective effect of OPC against alcohol-induced liver steatosis and injury, which could a potential drug for the treatment of alcohol-induced liver injury in the future. PMID:25680468

  15. In Vivo and In Vitro Antinociceptive Effect of Fagopyrum cymosum (Trev.) Meisn Extracts: A Possible Action by Recovering Intestinal Barrier Dysfunction

    PubMed Central

    Liu, Lina; Cai, Xueting; Yan, Jing; Luo, Yi; Shao, Ming; Lu, Yin; Sun, Zhiguang; Cao, Peng

    2012-01-01

    Fagopyrum cymosum (Trev.) Meisn (Fag) is a herb rhizome which has been widely used to treat diseases. To investigate the effects and mechanisms of the Fag on irritable bowel syndrome (IBS), in vivo neonatal pups maternal separation (NMS) combined with intracolonic infusion of acetic acid (AA) was employed to establish IBS rat models. Fag reduced their visceral hyperalgesia and the whole gut permeability, ameliorated colonic mucosa inflammation and injury, and upregulated the expression of decreased tight junction proteins (TJs) of claudin-1, occludin, and ZO-1 (except ZO-2) in colonic epithelium. Caco-2 monolayer cells were incubated with TNF-α and IFN-γ  in vitro to establish an epithelial barrier dysfunction model whose transepithelial electrical resistance (TER) depended more on dose of Fag than that of the controls, and whose TJs levels were lower than those of the controls. Fag upregulated the NP-40 insoluble and soluble components of the four TJs markedly in a dose-dependent manner. These data suggest that Fag alleviated the hyperalgesia of IBS rats by reducing intestinal inflammation and enhancing mucosal epithelial function after regulating the structure and function of TJs. PMID:23365604

  16. In vitro prediction of human intestinal absorption and blood-brain barrier partitioning: development of a lipid analog for micellar liquid chromatography.

    PubMed

    De Vrieze, Mike; Janssens, Pieter; Szucs, Roman; Van der Eycken, Johan; Lynen, Frédéric

    2015-09-01

    Over the past decades, several in vitro methods have been tested for their ability to predict either human intestinal absorption (HIA) or penetration across the blood-brain barrier (BBB) of drugs. Micellar liquid chromatography (MLC) has been a successful approach for retention time measurements of drugs to establish models together with other molecular descriptors. Thus far, MLC approaches have only made use of commercial surfactants such as sodium dodecyl sulfate (SDS) and polyoxyethylene (23) lauryl ether (Brij35), which are not representative for the phospholipids present in human membranes. Miltefosine, a phosphocholine-based lipid, is presented here as an alternative surfactant for MLC measurements. By using the obtained retention factors and several computed descriptors for a set of 48 compounds, two models were constructed: one for the prediction of HIA and another for the prediction of penetration across the BBB expressed as log BB. All data were correlated to experimental HIA and log BB values, and the performance of the models was evaluated. Log BB prediction performed better than HIA prediction, although HIA prediction was also improved a lot (from 0.5530 to 0.7175) compared to in silico predicted HIA values. PMID:26277183

  17. Vitamin A supplementation effects on intestinal barrier function, growth, total parasitic and specific Giardia spp. infections in Brazilian children: a prospective randomized, double-blind, placebo-controlled trial

    PubMed Central

    Lima, Aldo A. M.; Soares, Alberto M.; Lima, Noélia L.; Mota, Rosa M. S.; Maciel, Bruna L. L.; Kvalsund, Michelle P.; Barrett, Leah J.; Fitzgerald, Relana P.; Blaner, William S.; Guerrant, Richard L.

    2009-01-01

    Background This study evaluates the effects of retinol on intestinal barrier function, growth, total parasites and Giardia spp. infections in children in the Northeast of Brazil. Methods The study was a double-blind, randomized placebo-controlled trial (http://clinicaltrials.gov;Register#NCT00133406) involving 79children reiceved vitamin A 100,000 - 200,000 IU (n = 39) or placebo (n = 40) at enrollment, 4 and 8 months, followed for 36 months. Intestinal barrier function was evaluated using the lactulose:mannitol test. Stool lactoferrin was used as a marker for intestinal inflammation. Results The groups were similar with regard to age, sex, nutritional parameters (z-scores), serum retinol concentrations, proportion of lactoferrin positive stool samples, and intestinal barrier function. The lactulose:mannitol ratio did not change during the same time of follow-up (p>0.05). The proportion of lactoferrin positive samples evaluated at one month did not change between groups (p>0.05). Total intestinal parasitic specifically new infections were significantly lower in the vitamin A treatment compared to control group; these were accounted for entirely by significantly fewer new Giardia infections in the vitamin A treatment group. The cumulative z-scores for weight-for-length or height (WHZ), length or height-for-age z-scores (HAZ), and weight-for-age (WAZ) did not change significantly with vitamin A intervention for 36 months of follow-up. Conclusions These data showed that total parasitic infection and Giardia spp. infections were significantly lower in the vitamin A treatment group when compared to the placebo group, suggesting that vitamin A improves host defenses against Giardia infections. PMID:20038852

  18. Experimental rat model for alcohol-induced osteonecrosis of the femoral head

    PubMed Central

    Okazaki, Shunichiro; Nagoya, Satoshi; Tateda, Kenji; Katada, Ryuichi; Mizuo, Keisuke; Watanabe, Satoshi; Yamashita, Toshihiko; Matsumoto, Hiroshi

    2013-01-01

    Alcohol-induced osteonecrosis of the femoral head (ONFH) is observed in alcohol abusers and patients with alcoholic fatty liver disease. It has been reported that Toll-like receptor 4 (TLR4) signalling plays a crucial role in the pathogenesis of alcoholic fatty liver disease. We previously reported a corticosteroid-induced ONFH rat model, and suggested that TLR4 signalling contributes to the pathogenesis of ONFH. Thus, it is thought that the pathogenesis of alcohol-induced ONFH is probably similar to that of corticosteroid-induced ONFH. The aim of this study was to develop a new animal model for alcohol-induced ONFH and to evaluate the relationship between the pro-inflammatory response via TLRs and the development of ONFH in rats. Male Wistar rats were fed a Lieber–DeCarli liquid diet containing 5% ethanol (experimental group) or dextran (control group) for 1–24 weeks. Histopathological and biochemical analyses were performed. Feeding the ethanol-containing liquid diet resulted in the development of ONFH with hepatic steatosis, hepatic dysfunction and hyperlipidaemia, whereas feeding the dextran-containing diet did not cause ONFH. However, we could not recognize any relationship between the pro-inflammatory response via TLR4 and the development of alcohol-induced ONFH. Thus in this study we have developed a new rat model for alcohol-induced ONFH based on the feeding of an ethanol liquid diet. ONFH was observed within seven days from the start of feeding with 5% ethanol-containing liquid diet. Although this was linked to hepatic steatosis, a TLR4 association was not a feature of this model. PMID:24020403

  19. Circadian Modulation of Alcohol-Induced Sedation and Recovery in Male and Female Drosophila.

    PubMed

    De Nobrega, Aliza K; Lyons, Lisa C

    2016-04-01

    Delineating the factors that affect behavioral and neurological responses to alcohol is critical to facilitate measures for preventing or treating alcohol abuse. The high degree of conserved molecular and physiological processes makes Drosophila melanogaster a valuable model for investigating circadian interactions with alcohol-induced behaviors and examining sex-specific differences in alcohol sensitivity. We found that wild-type Drosophila exhibited rhythms in alcohol-induced sedation under light-dark and constant dark conditions with considerably greater alcohol exposure necessary to induce sedation during the late (subjective) day and peak sensitivity to alcohol occurring during the late (subjective) night. The circadian clock also modulated the recovery from alcohol-induced sedation with flies regaining motor control significantly faster during the late (subjective) day. As predicted, the circadian rhythms in sedation and recovery were absent in flies with a mutation in the circadian gene period or arrhythmic flies housed in constant light conditions. Flies lacking a functional circadian clock were more sensitive to the effects of alcohol with significantly longer recovery times. Similar to other animals and humans, Drosophila exhibit sex-specific differences in alcohol sensitivity. We investigated whether the circadian clock modulated the rhythms in the loss-of-righting reflex, alcohol-induced sedation, and recovery differently in males and females. We found that both sexes demonstrated circadian rhythms in the loss-of-righting reflex and sedation with the differences in alcohol sensitivity between males and females most pronounced during the late subjective day. Recovery of motor reflexes following alcohol sedation also exhibited circadian modulation in male and female flies, although the circadian clock did not modulate the difference in recovery times between the sexes. These studies provide a framework outlining how the circadian clock modulates alcohol-induced

  20. Toll-like receptor 2 activation by β2→1-fructans protects barrier function of T84 human intestinal epithelial cells in a chain length-dependent manner.

    PubMed

    Vogt, Leonie M; Meyer, Diederick; Pullens, Gerdie; Faas, Marijke M; Venema, Koen; Ramasamy, Uttara; Schols, Henk A; de Vos, Paul

    2014-07-01

    Dietary fiber intake is associated with lower incidence and mortality from disease, but the underlying mechanisms of these protective effects are unclear. We hypothesized that β2→1-fructan dietary fibers confer protection on intestinal epithelial cell barrier function via Toll-like receptor 2 (TLR2), and we studied whether β2→1-fructan chain-length differences affect this process. T84 human intestinal epithelial cell monolayers were incubated with 4 β2→1-fructan formulations of different chain-length compositions and were stimulated with the proinflammatory phorbol 12-myristate 13-acetate (PMA). Transepithelial electrical resistance (TEER) was analyzed by electric cell substrate impedance sensing (ECIS) as a measure for tight junction-mediated barrier function. To confirm TLR2 involvement in barrier modulation by β2→1-fructans, ECIS experiments were repeated using TLR2 blocking antibody. After preincubation of T84 cells with short-chain β2→1-fructans, the decrease in TEER as induced by PMA (62.3 ± 5.2%, P < 0.001) was strongly attenuated (15.2 ± 8.8%, P < 0.01). However, when PMA was applied first, no effect on recovery was observed during addition of the fructans. By blocking TLR2 on the T84 cells, the protective effect of short-chain β2→1-fructans was substantially inhibited. Stimulation of human embryonic kidney human TLR2 reporter cells with β2→1-fructans induced activation of nuclear factor kappa-light-chain-enhancer of activated B cells, confirming that β2→1-fructans are specific ligands for TLR2. To conclude, β2→1-fructans exert time-dependent and chain length-dependent protective effects on the T84 intestinal epithelial cell barrier mediated via TLR2. These results suggest that TLR2 located on intestinal epithelial cells could be a target of β2→1-fructan-mediated health effects. PMID:24790027

  1. Alcohol-induced hypertension: an important healthcare target in Belgium.

    PubMed

    Collart, F; de Timary, P; Dom, G; Dor, B D; Duprez, D; Lengelé, J-P; Matthys, F; Peuskens, H; Rehm, J; Stärkel, P

    2015-12-01

    Excessive alcohol intake is one of the leading causes of premature death in Europe and particularly in Belgium. Belgian people are consuming more alcohol per year than the European average. It is well established that excessive alcohol consumption is a significant predictor of the development of hypertension (HTN). Two million adults in Belgium suffer from HTN and this number will increase to three million by 2025. Less than 50% of Belgian people treated for HTN are well-controlled. Alcohol reduction in patients with HTN can significantly lower systolic and diastolic blood pressure. After reviewing the epidemiology of HTN and alcohol disorders in Belgium, this paper will focus on the rationale for alcohol screening and brief intervention in primary care. It will also describe the barriers to alcohol screening, and what could be the benefits of alcohol screening for our healthcare system. The authors believe that early identification through alcohol screening and brief intervention in general practice can help to improve the management of patients with HTN, to reach the targets of the WHO Global Action Plan, i.e., a 25% relative reduction in the risk of premature mortality from cardiovascular diseases, cancer, diabetes or chronic respiratory diseases. They are also convinced that this would allow achieving major healthcare savings. PMID:26135944

  2. 1,25-Dihydroxyvitamin D3 preserves intestinal epithelial barrier function from TNF-α induced injury via suppression of NF-kB p65 mediated MLCK-P-MLC signaling pathway.

    PubMed

    Chen, Shanwen; Zhu, Jing; Chen, Guowei; Zuo, Shuai; Zhang, Junling; Chen, Ziyi; Wang, Xin; Li, Junxia; Liu, Yucun; Wang, Pengyuan

    2015-05-01

    Substantial studies have demonstrated the protective effect of 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) on intestinal barrier function, but the mechanisms are not fully illustrated. In this study, the effect of 1,25(OH)2D3 on TNF-α induced barrier dysfunction was further investigated in Caco-2 cell monolayers. The barrier function of Caco-2 monolayers was evaluated by measuring trans-epithelial electrical resistance (TEER) and FITC-Dextran 40,000 Da (FD-40) trans-membrane flux. ZO-1 and Occludin were chosen as markers of the localization of tight junction (TJ) proteins for immunofluorescence. The expression of MLCK and phosphorylation level of myosin light chain (MLC) were measured by immunoblotting. The activation of NF-kB p65 was analyzed by EMSA and immunofluorescence. The results suggest that 1,25(OH)2D3 preserves intestinal epithelial barrier function from TNF-α induced injury via suppression of NF-kB p65 mediated activation of MLCK-P-MLC signaling pathway. PMID:25838204

  3. Urinary metabolic profiling of rat models revealed protective function of scoparone against alcohol induced hepatotoxicity

    PubMed Central

    Zhang, Aihua; Sun, Hui; Wang, Xijun

    2014-01-01

    Alcohol-induced liver disease (ALD) is a leading cause of non-accident-related deaths in the world. Identification of an early specific signature of ALD would aid in therapeutic intervention. Scoparone is an important constituent of Yinchenhao, and displayed bright prospects in hepatoprotective effect. However, its precise molecular mechanism has not been well explored. The present study was designed to assess the effects and possible mechanisms of scoparone against alcohol-induced liver injury. UPLC/ESI-Q-TOF/MS combined with pattern recognition approaches including PCA, and PLS-DA were integrated to get differentiating metabolites for the pathways and clarify mechanisms of disease, highlight insights into drug discovery. The results indicated four ions in the positive mode were characterized as potential differentiating metabolites which can be regulated by scoparone treatment, and suggested that therapeutic effect of scoparone could regulated the dysfunctions of citrate cycle, sphingolipid metabolism, taurine and hypotaurine. PMID:25341677

  4. Intestinal failure: Pathophysiological elements and clinical diseases

    PubMed Central

    Ding, Lian-An; Li, Jie-Shou

    2004-01-01

    There are two main functions of gastrointestinal tract, digestion and absorption, and barrier function. The latter has an important defensive effect, which keeps the body away from the invading and damaging of bacteria and endotoxin. It maintains the systemic homeostasis. Intestinal dysfunction would happen when body suffers from diseases or harmful stimulations. The lesser dysfunction of GI tract manifests only disorder of digestion and absorption, whereas the more serious intestinal disorders would harm the intestinal protective mechanism, or intestinal barrier function, and bacterial/endotoxin translocation, of intestinal failure (IF) would ensue. This review disscussed the theory of the intestinal failure, aiming at attracting recognition and valuable comments by clinicians. PMID:15052668

  5. Pharmacological ceramide reduction alleviates alcohol-induced steatosis and hepatomegaly in adiponectin knockout mice

    PubMed Central

    Correnti, Jason M.; Juskeviciute, Egle; Swarup, Aditi

    2014-01-01

    Hepatosteatosis, the ectopic accumulation of lipid in the liver, is one of the earliest clinical signs of alcoholic liver disease (ALD). Alcohol-dependent deregulation of liver ceramide levels as well as inhibition of AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor α (PPAR-α) activity are thought to contribute to hepatosteatosis development. Adiponectin can regulate lipid handling in the liver and has been shown to reduce ceramide levels and activate AMPK and PPAR-α. However, the mechanisms by which adiponectin prevents alcoholic hepatosteatosis remain incompletely characterized. To address this question, we assessed ALD progression in wild-type (WT) and adiponectin knockout (KO) mice fed an ethanol-containing liquid diet or isocaloric control diet. Adiponectin KO mice relative to WT had increased alcohol-induced hepatosteatosis and hepatomegaly, similar modest increases in serum alanine aminotransferase, and reduced liver TNF. Restoring circulating adiponectin levels using recombinant adiponectin ameliorated alcohol-induced hepatosteatosis and hepatomegaly in adiponectin KO mice. Alcohol-fed WT and adiponectin KO animals had equivalent reductions in AMPK protein and PPAR-α DNA binding activity compared with control-fed animals. No difference in P-AMPK/AMPK ratio was detected, suggesting that alcohol-dependent deregulation of AMPK and PPAR-α in the absence of adiponectin are not primary causes of the observed increase in hepatosteatosis in these animals. By contrast, alcohol treatment increased liver ceramide levels in adiponectin KO but not WT mice. Importantly, pharmacological inhibition of de novo ceramide synthesis in adiponectin KO mice abrogated alcohol-mediated increases in liver ceramides, steatosis, and hepatomegaly. These data suggest that adiponectin reduces alcohol-induced steatosis and hepatomegaly through regulation of liver ceramides, but its absence does not exacerbate alcohol-induced liver damage. PMID

  6. Targeting Pin1 Protects Mouse Cardiomyocytes from High-Dose Alcohol-Induced Apoptosis

    PubMed Central

    Wang, Yuehong; Li, Zizhuo; Zhang, Yu; Yang, Wei; Sun, Jiantao; Shan, Lina; Li, Weimin

    2016-01-01

    Long-term heavy alcohol consumption is considered to be one of the main causes of left ventricular dysfunction in alcoholic cardiomyopathy (ACM). As previously suggested, high-dose alcohol induces oxidation stress and apoptosis of cardiomyocytes. However, the underlying mechanisms are yet to be elucidated. In this study, we found that high-dose alcohol treatment stimulated expression and activity of Pin1 in mouse primary cardiomyocytes. While siRNA-mediated knockdown of Pin1 suppressed alcohol-induced mouse cardiomyocyte apoptosis, overexpression of Pin1 further upregulated the numbers of apoptotic mouse cardiomyocytes. We further demonstrated that Pin1 promotes mitochondria oxidative stress and loss of mitochondrial membrane potential but suppresses endothelial nitric oxide synthase (eNOS) expression in the presence of alcohol. Taken together, our results revealed a pivotal role of Pin1 in regulation of alcohol-induced mouse cardiomyocytes apoptosis by promoting reactive oxygen species (ROS) accumulation and repressing eNOS expression, which could be potential therapeutic targets for ACM. PMID:26697133

  7. Peroxisome Proliferator-Activated Receptor γ Regulates Chronic Alcohol-Induced Alveolar Macrophage Dysfunction.

    PubMed

    Yeligar, Samantha M; Mehta, Ashish J; Harris, Frank L; Brown, Lou Ann S; Hart, C Michael

    2016-07-01

    Peroxisome proliferator-activated receptor (PPAR) γ is critical for alveolar macrophage (AM) function. Chronic alcohol abuse causes AM phagocytic dysfunction and susceptibility to respiratory infections by stimulating nicotinamide adenine dinucleotide oxidases (Nox), transforming growth factor-β1, and oxidative stress in the AM. Because PPARγ inhibits Nox expression, we hypothesized that alcohol reduces PPARγ, stimulating AM dysfunction. AMs were examined from: (1) patients with alcoholism or control patients; (2) a mouse model of chronic ethanol consumption; (3) PPARγ knockout mice; or (4) MH-S cells exposed to ethanol in vitro. Alcohol reduced AM PPARγ levels and increased Nox1, -2, and -4, transforming growth factor-β1, oxidative stress, and phagocytic dysfunction. Genetic loss of PPARγ recapitulated, whereas stimulating PPARγ activity attenuated alcohol-mediated alterations in gene expression and phagocytic function, supporting the importance of PPARγ in alcohol-induced AM derangements. Similarly, PPARγ activation in vivo reduced alcohol-mediated impairments in lung bacterial clearance. Alcohol increased levels of microRNA-130a/-301a, which bind to the PPARγ 3' untranslated region to reduce PPARγ expression. MicroRNA-130a/-301a inhibition attenuated alcohol-mediated PPARγ reductions and derangements in AM gene expression and function. Alcohol-induced Toll-like receptor 4 endocytosis was reversed by PPARγ activation. These findings demonstrate that targeting PPARγ provides a novel therapeutic approach for mitigating alcohol-induced AM derangements and susceptibility to lung infection. PMID:26677910

  8. Fibroblast growth factor 21 deficiency exacerbates chronic alcohol-induced hepatic steatosis and injury

    PubMed Central

    Liu, Yanlong; Zhao, Cuiqing; Xiao, Jian; Liu, Liming; Zhang, Min; Wang, Cuiling; Wu, Guicheng; Zheng, Ming-Hua; Xu, Lan-Man; Chen, Yong-Ping; Mohammadi, Moosa; Chen, Shao-Yu; Cave, Matthew; McClain, Craig; Li, Xiaokun; Feng, Wenke

    2016-01-01

    Fibroblast growth factor 21 (FGF21) is a hepatokine that regulates glucose and lipid metabolism in the liver. We sought to determine the role of FGF21 in hepatic steatosis in mice exposed to chronic alcohol treatment and to discern underlying mechanisms. Male FGF21 knockout (FGF21 KO) and control (WT) mice were divided into groups that were fed either the Lieber DeCarli diet containing 5% alcohol or an isocaloric (control) diet for 4 weeks. One group of WT mice exposed to alcohol received recombinant human FGF21 (rhFGF21) in the last 5 days. Liver steatosis and inflammation were assessed. Primary mouse hepatocytes and AML-12 cells were incubated with metformin or rhFGF21. Hepatic genes and the products involved in in situ lipogenesis and fatty acid β-oxidation were analyzed. Alcohol exposure increased circulating levels and hepatic expression of FGF21. FGF21 depletion exacerbated alcohol-induced hepatic steatosis and liver injury, which was associated with increased activation of genes involved in lipogenesis mediated by SREBP1c and decreased expression of genes involved in fatty acid β-oxidation mediated by PGC1α. rhFGF21 administration reduced alcohol-induced hepatic steatosis and inflammation in WT mice. These results reveal that alcohol-induced FGF21 expression is a hepatic adaptive response to lipid dysregulation. Targeting FGF21 signaling could be a novel treatment approach for alcoholic steatohepatitis. PMID:27498701

  9. Fibroblast growth factor 21 deficiency exacerbates chronic alcohol-induced hepatic steatosis and injury.

    PubMed

    Liu, Yanlong; Zhao, Cuiqing; Xiao, Jian; Liu, Liming; Zhang, Min; Wang, Cuiling; Wu, Guicheng; Zheng, Ming-Hua; Xu, Lan-Man; Chen, Yong-Ping; Mohammadi, Moosa; Chen, Shao-Yu; Cave, Matthew; McClain, Craig; Li, Xiaokun; Feng, Wenke

    2016-01-01

    Fibroblast growth factor 21 (FGF21) is a hepatokine that regulates glucose and lipid metabolism in the liver. We sought to determine the role of FGF21 in hepatic steatosis in mice exposed to chronic alcohol treatment and to discern underlying mechanisms. Male FGF21 knockout (FGF21 KO) and control (WT) mice were divided into groups that were fed either the Lieber DeCarli diet containing 5% alcohol or an isocaloric (control) diet for 4 weeks. One group of WT mice exposed to alcohol received recombinant human FGF21 (rhFGF21) in the last 5 days. Liver steatosis and inflammation were assessed. Primary mouse hepatocytes and AML-12 cells were incubated with metformin or rhFGF21. Hepatic genes and the products involved in in situ lipogenesis and fatty acid β-oxidation were analyzed. Alcohol exposure increased circulating levels and hepatic expression of FGF21. FGF21 depletion exacerbated alcohol-induced hepatic steatosis and liver injury, which was associated with increased activation of genes involved in lipogenesis mediated by SREBP1c and decreased expression of genes involved in fatty acid β-oxidation mediated by PGC1α. rhFGF21 administration reduced alcohol-induced hepatic steatosis and inflammation in WT mice. These results reveal that alcohol-induced FGF21 expression is a hepatic adaptive response to lipid dysregulation. Targeting FGF21 signaling could be a novel treatment approach for alcoholic steatohepatitis. PMID:27498701

  10. The alcohol-induced locomotor stimulation and accumbal dopamine release is suppressed in ghrelin knockout mice.

    PubMed

    Jerlhag, Elisabet; Landgren, Sara; Egecioglu, Emil; Dickson, Suzanne L; Engel, Jörgen A

    2011-06-01

    Ghrelin, the first endogenous ligand for the type 1A growth hormone secretagogue receptor (GHS-R1A), plays a role in energy balance, feeding behavior, and reward. Previously, we showed that pharmacologic and genetic suppression of the GHS-R1A attenuates the alcohol-induced stimulation, accumbal dopamine release, and conditioned place preference as well as alcohol consumption in mice, implying that the GHS-R1A is required for alcohol reward. The present study further elucidates the role of ghrelin for alcohol-induced dopamine release in nucleus accumbens and locomotor stimulation by means of ghrelin knockout mice. We found that the ability of alcohol to increase accumbal dopamine release in wild-type mice is not observed in ghrelin knockout mice. Furthermore, alcohol induced a locomotor stimulation in the wild-type mice and ghrelin knockout mice; however, the locomotor stimulation in homozygote mice was significantly lower than in the wild-type mice. The present series of experiments suggest that endogenous ghrelin may be required for the ability of alcohol to activate the mesolimbic dopamine system. PMID:21145690

  11. Microglial AGE-albumin is critical in promoting alcohol-induced neurodegeneration in rats and humans.

    PubMed

    Byun, Kyunghee; Bayarsaikhan, Delger; Bayarsaikhan, Enkhjargal; Son, Myeongjoo; Oh, Seyeon; Lee, Jaesuk; Son, Hye-In; Won, Moo-Ho; Kim, Seung U; Song, Byoung-Joon; Lee, Bonghee

    2014-01-01

    Alcohol is a neurotoxic agent, since long-term heavy ingestion of alcohol can cause various neural diseases including fetal alcohol syndrome, cerebellar degeneracy and alcoholic dementia. However, the molecular mechanisms of alcohol-induced neurotoxicity are still poorly understood despite numerous studies. Thus, we hypothesized that activated microglial cells with elevated AGE-albumin levels play an important role in promoting alcohol-induced neurodegeneration. Our results revealed that microglial activation and neuronal damage were found in the hippocampus and entorhinal cortex following alcohol treatment in a rat model. Increased AGE-albumin synthesis and secretion were also observed in activated microglial cells after alcohol exposure. The expressed levels of receptor for AGE (RAGE)-positive neurons and RAGE-dependent neuronal death were markedly elevated by AGE-albumin through the mitogen activated protein kinase pathway. Treatment with soluble RAGE or AGE inhibitors significantly diminished neuronal damage in the animal model. Furthermore, the levels of activated microglial cells, AGE-albumin and neuronal loss were significantly elevated in human brains from alcoholic indivisuals compared to normal controls. Taken together, our data suggest that increased AGE-albumin from activated microglial cells induces neuronal death, and that efficient regulation of its synthesis and secretion is a therapeutic target for preventing alcohol-induced neurodegeneration. PMID:25140518

  12. Effect of a Semi-Purified Oligosaccharide-Enriched Fraction from Caprine Milk on Barrier Integrity and Mucin Production of Co-Culture Models of the Small and Large Intestinal Epithelium.

    PubMed

    Barnett, Alicia M; Roy, Nicole C; McNabb, Warren C; Cookson, Adrian L

    2016-01-01

    Caprine milk contains the highest amount of oligosaccharides among domestic animals, which are structurally similar to human milk oligosaccharides (HMOs). This suggests caprine milk oligosaccharides may offer similar protective and developmental effects to that of HMOs. However, to date, studies using oligosaccharides from caprine milk have been limited. Thus, this study aimed to examine the impact of a caprine milk oligosaccharide-enriched fraction (CMOF) on barrier function of epithelial cell co-cultures of absorptive enterocytes (Caco-2 cells) and mucus-secreting goblet cells (HT29-MTX cells), that more closely simulate the cell proportions found in the small (90:10) and large intestine (75:25). Treatment of epithelial co-cultures with 0.4, 1.0, 2.0 and 4.0 mg/mL of CMOF was shown to have no effect on metabolic activity but did enhance cell epithelial barrier integrity as measured by trans-epithelial electrical resistance (TEER), in a dose-dependent manner. The CMOF at the maximum concentration tested (4.0 mg/mL) enhanced TEER, mucin gene expression and mucin protein abundance of epithelial co-cultures, all of which are essential components of intestinal barrier function. PMID:27164134

  13. Effect of a Semi-Purified Oligosaccharide-Enriched Fraction from Caprine Milk on Barrier Integrity and Mucin Production of Co-Culture Models of the Small and Large Intestinal Epithelium

    PubMed Central

    Barnett, Alicia M.; Roy, Nicole C.; McNabb, Warren C.; Cookson, Adrian L.

    2016-01-01

    Caprine milk contains the highest amount of oligosaccharides among domestic animals, which are structurally similar to human milk oligosaccharides (HMOs). This suggests caprine milk oligosaccharides may offer similar protective and developmental effects to that of HMOs. However, to date, studies using oligosaccharides from caprine milk have been limited. Thus, this study aimed to examine the impact of a caprine milk oligosaccharide-enriched fraction (CMOF) on barrier function of epithelial cell co-cultures of absorptive enterocytes (Caco-2 cells) and mucus-secreting goblet cells (HT29-MTX cells), that more closely simulate the cell proportions found in the small (90:10) and large intestine (75:25). Treatment of epithelial co-cultures with 0.4, 1.0, 2.0 and 4.0 mg/mL of CMOF was shown to have no effect on metabolic activity but did enhance cell epithelial barrier integrity as measured by trans-epithelial electrical resistance (TEER), in a dose-dependent manner. The CMOF at the maximum concentration tested (4.0 mg/mL) enhanced TEER, mucin gene expression and mucin protein abundance of epithelial co-cultures, all of which are essential components of intestinal barrier function. PMID:27164134

  14. The Goblet Cell Protein Clca1 (Alias mClca3 or Gob-5) Is Not Required for Intestinal Mucus Synthesis, Structure and Barrier Function in Naive or DSS-Challenged Mice

    PubMed Central

    Mundhenk, Lars; Arike, Liisa; Glauben, Rainer; Heimesaat, Markus M.; Fischer, André; Bereswill, Stefan; Birchenough, George M. H.; Gruber, Achim D.; Johansson, Malin E. V.

    2015-01-01

    The secreted, goblet cell-derived protein Clca1 (chloride channel regulator, calcium-activated-1) has been linked to diseases with mucus overproduction, including asthma and cystic fibrosis. In the intestine Clca1 is found in the mucus with an abundance and expression pattern similar to Muc2, the major structural mucus component. We hypothesized that Clca1 is required for the synthesis, structure or barrier function of intestinal mucus and therefore compared wild type and Clca1-deficient mice under naive and at various time points of DSS (dextran sodium sulfate)-challenged conditions. The mucus phenotype in Clca1-deficient compared to wild type mice was systematically characterized by assessment of the mucus protein composition using proteomics, immunofluorescence and expression analysis of selected mucin genes on mRNA level. Mucus barrier integrity was assessed in-vivo by analysis of bacterial penetration into the mucus and translocation into sentinel organs combined analysis of the fecal microbiota and ex-vivo by assessment of mucus penetrability using beads. All of these assays revealed no relevant differences between wild type and Clca1-deficient mice under steady state or DSS-challenged conditions in mouse colon. Clca1 is not required for mucus synthesis, structure and barrier function in the murine colon. PMID:26162072

  15. Diosmectite-zinc oxide composite improves intestinal barrier function, modulates expression of pro-inflammatory cytokines and tight junction protein in early weaned pigs.

    PubMed

    Hu, Caihong; Song, Juan; Li, Yali; Luan, Zhaoshuang; Zhu, Kang

    2013-08-01

    The study evaluated whether feeding diosmectite-ZnO composite (DS-ZnO) at 500 mg Zn/kg to early weaned pigs would alleviate the weaning-related intestinal disorders as a substitute for high concentration of ZnO (2250 mg Zn/kg). The pigs weaned at an age of 21 ± 1 d were allotted to four treatments groups as follows: (1) control; (2) DS-ZnO, 500 mg Zn/kg diet; (3) ZnO, 2250 mg Zn/kg diet; and (4) mixture of 2·0 g DS/kg and 500 mg Zn/kg from ZnO (equal amount of DS and ZnO in the DS-ZnO treatment group). The results showed that, compared with the control on days 7 and 14 post-weaning, addition of DS-ZnO at 500 mg Zn/kg improved (P<0·05) daily gain and feed intake, decreased (P<0·05) post-weaning scour scores, increased (P<0·05) jejunal villus height and the ratio of villus height and crypt depth, decreased (P<0·05) jejunal paracellular permeability of fluorescein isothiocyanate dextran 4 kDa and up-regulated (P<0·05) tight junction protein expression of occludin, claudin-1 and zonula occludens-1 in jejunal mucosa. The mRNA levels of TNF-α, IL-6 and interferon-γ (IFN-γ) on day 7 post-weaning were also decreased (P<0·05). The piglets fed DS-ZnO at 500 mg Zn/kg did not differ in the above parameters from those fed ZnO at 2250 mg Zn/kg, while they had better performance than those fed the mixture of DS and ZnO. Supplementation with DS-ZnO at 500 mg Zn/kg was effective in alleviating diarrhoea, barrier dysfunction and inflammatory cytokine expression and up-regulating tight junction protein expression. PMID:23308387

  16. Effects of l-carnitine and/or maize distillers dried grains with solubles in diets of gestating and lactating sows on the intestinal barrier functions of their offspring.

    PubMed

    Wei, Bingdong; Nie, Shaoping; Meng, Qingwei; Qu, Zhe; Shan, Anshan; Chen, Zhihui

    2016-08-01

    The objective of this study was to investigate the effects of l-carnitine and/or maize distillers dried grains with solubles (DDGS) in diets of gestating and lactating sows on the intestinal barrier functions of their offspring. The experiment was designed as a 2×2 factorial with two dietary treatments (soyabean meal v. DDGS) and two l-carnitine levels (0 v. 100 mg/kg in gestating diets and 0 v. 200 mg/kg in lactating diets). Sows (Landrace×Large White) with an average parity of 4·2 with similar body weight were randomly assigned to four groups of thirty each. Dietary supplementation with l-carnitine increased the total superoxide dismutase activity but decreased the concentration of malondialdehyde of the jejunal mucosa in newborn piglets and weaning piglets on day 21. Dietary supplementation with l-carnitine decreased the concentrations of IL-1β, IL-12 and TNF-α in the jejunal mucosa of newborn piglets and decreased the concentrations of IL-6 and TNF-α in the jejunal mucosa of weaning piglets on day 21. There was an interaction between dietary treatment and l-carnitine on the bacterial numbers of total eubacteria in the digesta of caecum in weaning piglets on day 21. Bacterial numbers of total eubacteria in weaning piglets on day 21 were significantly increased by l-carnitine only in soyabean meal diet, but there was no significant effect of l-carnitine in DDGS-based diet. Dietary supplementation with l-carnitine increased the bacterial numbers of Lactobacillus spp. and bifidobacteria spp. in the digesta of caecum in weaning piglets on day 21. Dietary supplementation with l-carnitine in sows affected the expression of tight junction proteins (claudin 1, zonula occludens-1 (ZO-1) and occludin) in the jejunal mucosa of their offspring by increasing the expression of ZO-1 mRNA in the jejunal mucosa of newborn piglets, and by increasing the expression of ZO-1 and occludin mRNA in the jejunal mucosa of weaning piglets on day 21. In conclusion, dietary

  17. "Green" synthesized and coated nanaosilver alters the membrance permeability of barrier (intestinal, brain, endothelial) cells and stimulates oxidative stress pathways in neurons.

    EPA Science Inventory

    Nanosilver's (nanoAg) use in medical applications and consumer products is increasing. Because of this, its "green" synthesis and surface modification with beneficial coatings are desirable. Given nanoAg's potential exposure routes (e.g., dermal, intestin...

  18. Intestinal leiomyoma

    MedlinePlus

    Leiomyoma - intestine ... McLaughlin P, Maher MM. The duodenum and small intestine. In: Adam A, Dixon AK, Gillard JH, Schaefer- ... Roline CE, Reardon RF. Disorders of the small intestine. In: Marx JA, Hockberger RS, Walls RM, et ...

  19. Intestinal Cancer

    MedlinePlus

    ... connects your stomach to your large intestine. Intestinal cancer is rare, but eating a high-fat diet ... increase your risk. Possible signs of small intestine cancer include Abdominal pain Weight loss for no reason ...

  20. Decreased hepatic iron in response to alcohol may contribute to alcohol-induced suppression of hepcidin.

    PubMed

    Varghese, Joe; James, Jithu Varghese; Sagi, Sreerohini; Chakraborty, Subhosmito; Sukumaran, Abitha; Ramakrishna, Banumathi; Jacob, Molly

    2016-06-01

    Hepatic Fe overload has often been reported in patients with advanced alcoholic liver disease. However, it is not known clearly whether it is the effect of alcohol that is responsible for such overload. To address this lacuna, a time-course study was carried out in mice in order to determine the effect of alcohol on Fe homoeostasis. Male Swiss albino mice were pair-fed Lieber-DeCarli alcohol diet (20 % of total energy provided as alcohol) for 2, 4, 8 or 12 weeks. Expression levels of duodenal and hepatic Fe-related proteins were determined by quantitative PCR and Western blotting, as were Fe levels and parameters of oxidative stress in the liver. Alcohol induced cytochrome P4502E1 and oxidative stress in the liver. Hepatic Fe levels and ferritin protein expression dropped to significantly lower levels after 12 weeks of alcohol feeding, with no significant effects at earlier time points. This was associated, at 12 weeks, with significantly decreased liver hepcidin expression and serum hepcidin levels. Protein expressions of duodenal ferroportin (at 8 and 12 weeks) and divalent metal transporter 1 (at 8 weeks) were increased. Serum Fe levels rose progressively to significantly higher levels at 12 weeks. Histopathological examination of the liver showed mild steatosis, but no stainable Fe in mice fed alcohol for up to 12 weeks. In summary, alcohol ingestion by mice in this study affected several Fe-related parameters, but produced no hepatic Fe accumulation. On the contrary, alcohol-induced decreases in hepatic Fe levels were seen and may contribute to alcohol-induced suppression of hepcidin. PMID:27080262

  1. Reduced early alcohol-induced liver injury in CD14-deficient mice.

    PubMed

    Yin, M; Bradford, B U; Wheeler, M D; Uesugi, T; Froh, M; Goyert, S M; Thurman, R G

    2001-04-01

    Activation of Kupffer cells by gut-derived endotoxin is associated with alcohol-induced liver injury. Recently, it was shown that CD14-deficient mice are more resistant to endotoxin-induced shock than wild-type controls. Therefore, this study was designed to investigate the role of CD14 receptors in early alcohol-induced liver injury using CD14 knockout and wild-type BALB/c mice in a model of enteral ethanol delivery. Animals were given a high-fat liquid diet continuously with ethanol or isocaloric maltose-dextrin as control for 4 wk. The liver to body weight ratio in wild-type mice (5.8 +/- 0.3%) was increased significantly by ethanol (7.3 +/- 0.2%) but was not altered by ethanol in CD14-deficient mice. Ethanol elevated serum alanine aminotransferase levels nearly 3-fold in wild-type mice, but not in CD14-deficient mice. Wild-type and knockout mice given the control high-fat diet had normal liver histology, whereas ethanol caused severe liver injury (steatosis, inflammation, and necrosis; pathology score = 3.8 +/- 0.4). In contrast, CD14-deficient mice given ethanol showed minimal hepatic changes (score = 1.6 +/- 0.3, p < 0.05). Additionally, NF-kappa B, TGF-beta, and TNF-alpha were increased significantly in wild-type mice fed ethanol but not in the CD14 knockout. Thus, chronic ethanol feeding caused more severe liver injury in wild-type than CD14 knockouts, supporting the hypothesis that endotoxin acting via CD14 plays a major role in the development of early alcohol-induced liver injury. PMID:11254735

  2. Development and Optimization of a Novel Prolonged Release Formulation to Resist Alcohol-Induced Dose Dumping.

    PubMed

    Gujjar, Chaitanya Yogananda; Rallabandi, Balaramesha Chary; Gannu, Ramesh; Deulkar, Vallabh Subashrao

    2016-04-01

    Alcohol-induced dose dumping is a serious concern for the orally administered prolonged release dosage forms. The study was designed to optimize the independent variables, propylene glycol alginate (PGA), Eudragit RS PO (ERS) and coating in mucoadhesive quetiapine prolonged release tablets 200 mg required for preventing the alcohol-induced dose dumping. Optimal design based on response surface methodology was employed for the optimization of the composition. The formulations are evaluated for in vitro drug release in hydrochloric acid alone and with 40% v/v ethanol. The responses, dissolution at 120 min without alcohol (R1) and dissolution at 120 min with alcohol (R2), were statistically evaluated and regression equations are generated. PGA as a hydrophilic polymeric matrix was dumping the dose when dissolutions are carried in 0.1 N hydrochloric acid containing 40% v/v ethanol. ERS addition was giving structural support to the swelling and gelling property of PGA, and thus, was reducing the PGA erosion in dissolution media containing ethanol. Among the formulations, four formulations with diverse composition were meeting the target dissolution (30-40%) in both the conditions. The statistical validity of the mathematical equations was established, and the optimum concentration of the factors was established. Validation of the study with six confirmatory runs indicated high degree of prognostic ability of response surface methodology. Further coating with ReadiLycoat was providing an additional resistance to the alcohol-induced dose dumping. Optimized compositions showed resistance to dose dumping in the presence of alcohol. PMID:26162975

  3. Claudins in intestines

    PubMed Central

    Lu, Zhe; Ding, Lei; Lu, Qun; Chen, Yan-Hua

    2013-01-01

    Intestines are organs that not only digest food and absorb nutrients, but also provide a defense barrier against pathogens and noxious agents ingested. Tight junctions (TJs) are the most apical component of the junctional complex, providing one form of cell-cell adhesion in enterocytes and playing a critical role in regulating paracellular barrier permeability. Alteration of TJs leads to a number of pathophysiological diseases causing malabsorption of nutrition and intestinal structure disruption, which may even contribute to systemic organ failure. Claudins are the major structural and functional components of TJs with at least 24 members in mammals. Claudins have distinct charge-selectivity, either by tightening the paracellular pathway or functioning as paracellular channels, regulating ions and small molecules passing through the paracellular pathway. In this review, we have discussed the functions of claudin family members, their distribution and localization in the intestinal tract of mammals, their alterations in intestine-related diseases and chemicals/agents that regulate the expression and localization of claudins as well as the intestinal permeability, which provide a therapeutic view for treating intestinal diseases. PMID:24478939

  4. The common prophylactic therapy for bowel surgery is ineffective for clearing Bacteroidetes, the primary inducers of systemic inflammation, and causes faster death in response to intestinal barrier damage in mice

    PubMed Central

    Sinsimer, Daniel; Esseghir, Amira; Tang, May; Laouar, Amale

    2014-01-01

    Introduction and objective The role of secreted gut microbial components in the initiation of systemic inflammation and consequences of antibiotic therapies on this inflammatory process are poorly elucidated. We investigate whether peripheral innate cells mount an inflammatory response to gut microbial components, the immune cells that are the primary drivers of systemic inflammation, the bacterial populations that are predominantly responsible, and whether perioperative antibiotics affect these processes. Method and experimental design Conditioned supernatants from gut microbes were used to stimulate murine innate cell types in vitro and in vivo, and proinflammatory responses were characterised. Effects of antibiotic therapies on these responses were investigated using a model of experimental intestinal barrier damage induced by dextran sodium sulfate. Results Proinflammatory responses in the periphery are generated by components of anaerobes from the Bacteroidetes phylotype and these responses are primarily produced by myeloid dendritic cells. We found that the common prophylactic therapy for sepsis (oral neomycin and metronidazole administered to patients the day prior to surgery) is ineffective for clearing Bacteroidetes from the murine intestine. A point of critical consequence of this result is the increased systemic inflammation and premature death observed in treated mice, and these outcomes appear to be independent of gut bacterial spread in the initial phase of intestinal barrier damage. Importantly, spillage of gut microbial products, rather than dissemination of gut microbes, may underlay the initiation of systemic inflammation leading to death. Conclusions Our data further affirm the importance of a balanced gut microflora biodiversity in host immune homeostasis and reinforce the notion that inadequate antibiotic therapy can have detrimental effects on overall immune system. PMID:26462264

  5. Denatured globular protein and bile salt-coated nanoparticles for poorly water-soluble drugs: Penetration across the intestinal epithelial barrier into the circulation system and enhanced oral bioavailability.

    PubMed

    He, Wei; Yang, Ke; Fan, Lifang; Lv, Yaqi; Jin, Zhu; Zhu, Shumin; Qin, Chao; Wang, Yiao; Yin, Lifang

    2015-11-10

    Oral drug delivery is the most preferred route for patients; however, the low solubility of drugs and the resultant poor absorption compromise the benefits of oral administration. On the other hand, for years, the overwhelmingly accepted mechanism for enhanced oral absorption using lipid nanocarriers was based on the process of lipid digestion and drug solubilization in the small intestine. Few reports indicated that other bypass pathways are involved in drug absorption in the gastrointestinal tract (GIT) for oral delivery of nanocarriers. Herein, we report a new nanoemulsion system with a denatured globular protein with a diameter of 30 nm, soybean protein isolates (SPI), and bile salt as emulsifiers, aiming to enhance the absorption of insoluble drugs and explore other pathways for absorption. A BCS class II drug, fenofibrate (FB), was used as the model drug. The SPI and bile salt-coated Ns with a diameter of approximately 150 nm were prepared via a high-pressure homogenizing procedure. Interestingly, the present Ns could be converted to solid dosage form using fluid-bed coating technology, maintaining a nanoscale size. Most importantly, in a model of in situ rat intestinal perfusion, Ns could penetrate across the intestinal epithelial barrier into the systemic circulation and then obtain biodistribution into other tissues. In addition, Ns significantly improved FB oral absorption, exhibited as a greater than 2- and 2.5-fold increase in Cmax and AUC0-t, respectively, compared to the suspension formulation. Overall, the present Ns are promising nanocarriers for the oral delivery of insoluble drugs, and the penetration of intact Ns across the GIT barrier into systemic circulation may be a new strategy for improved drug absorption with the use of nanocarriers. PMID:26325310

  6. Gender differences in alcohol-induced oxidative stress and altered membrane properties in erythrocytes of rats.

    PubMed

    Reddy, Kindinti Rameshwar; Reddy, Vaddi Damodara; Padmavathi, Pannuru; Kavitha, Godugu; Saradamma, Bulle; Varadacharyulu, N C

    2013-02-01

    Alcohol-induced oxidative stress leads to imbalance between reactive oxygen species (ROS) and the antioxidant defense system, resulting in oxidative damage to membrane components such as lipids and proteins, ultimately altering membrane properties. In this study, we assessed oxidative stress status and alterations in erythrocyte membrane properties in alcohol-administered rats with respect to gender difference. Alcohol (20% v/v) administered rats of both genders showed significant changes in plasma lipid profile with elevated nitrite/nitrate levels. Furthermore, alcohol-administration significantly decreased erythrocyte antioxidant enzymes and enhanced erythrocyte membrane lipid peroxidation, cholesterol/phospholipid (C/P) ratio and Na+/K(+)-ATPase activity in both males and females. Besides, anisotropic studies revealed that alcohol-administration significantly decreased erythrocyte membrane fluidity. In conclusion, alcohol-administration significantly increased oxidative stress by decreasing antioxidant status, and subsequent generation of ROS altered membrane properties by altering fluidity and Na+/K(+)-ATPase activity. Female rats were more vulnerable to alcohol-induced biochemical and biophysical changes in plasma and erythrocyte including oxidative stress than male rats. PMID:23617072

  7. Effect of indomethacin on alcohol-induced morphological anomalies in mice

    SciTech Connect

    Randall, C.L.; Anton, R.F.; Becker, H.C.

    1987-07-20

    The purpose of the present study was 1) to examine the effect of indomethacin (INDO), a prostaglandin synthesis inhibitor, on alcohol-induced growth and morphological impairment in C57BL/6J mice (Study 1) and 2) to determine if INDO crosses the placenta (Study 2). On day 10 of gestation, mice were injected (s.c.) acutely with either 0, 5, 10, or 20 mg/kg INDO, followed one hour later by alcohol (5.8 g/kg orally) or isocaloric sucrose. Fetuses were removed on day 19 of pregnancy, weighed, and examined for anomalous development. As expected, Study 1 demonstrated that maternal alcohol treatment decreased fetal weight and increased the number of fetuses with birth defects. INDO alone decreased fetal weight but did not affect morphologic development. More importantly, INDO antagonized alcohol-induced birth defects, but only at the highest dose. The results of Study 2 suggest that the relative ineffectiveness of INDO may be related to its inability to readily cross the placenta. Since high doses of INDO also caused maternal toxicity, the usefulness of this compound in future studies of this type was questioned. 22 references, 4 tables.

  8. Thymoquinone Inhibition of Acquisition and Expression of Alcohol-Induced Behavioral Sensitization.

    PubMed

    Khan, Muhammad Sona; Gohar, Aneela; Abbas, Ghulam; Mahmood, Wajahat; Rauf, Khalid; Sewell, Robert D E

    2015-10-01

    Repeated low doses of alcohol have been shown to progressively enhance locomotor activity in mice, and this phenomenon is designated as behavioral sensitization. Thymoquinone, a major active component of Nigella sativa oil has been investigated in a number of studies for its neuroprotective effects against a variety of ailments. This study was conducted to explore the therapeutic potential of thymoquinone on the acquisition and expression of alcohol-induced behavioral sensitization. Mice treated with alcohol (2.2 g/kg/day) or saline for 13 days and subsequently challenged with an acute alcohol dose (2.2 g/kg) 5 days later were orally administered acute doses of thymoquinone (10, 20 and 30 mg/kg). Thymoquinone subacute treatment with all doses throughout alcohol exposure significantly inhibited both the development and expression phases of alcohol behavioral sensitization in a dose-dependent manner. However, acute treatment with thymoquinone (30 mg/kg) only reversed the expression phase of sensitization. These findings are explained in terms of the known GABA promoting action of thymoquinone in relation to the motive circuit within the limbic component of the basal ganglia. It is concluded that thymoquinone may be a potential therapeutic option for the treatment and prevention of alcohol induced behavioral sensitization. PMID:26171893

  9. Amelioration effects of traditional Chinese medicine on alcohol-induced fatty liver

    PubMed Central

    Kwon, Hyun-Jeong; Kim, Yun-Young; Choung, Se-Young

    2005-01-01

    AIM: To examine the effects of traditional Chinese medicine (TCM) on alcohol-induced fatty liver in rats. TCM consists of Astragalus membranaceus, Morus alba, Crataegus pinnatifida, Alisma orientale, Salvia miltiorrhiza, and Pueraria lobata. METHODS: The rats were separated randomly into five groups. One (the CD group) was fed a control diet for 10 wk, another (the ED group) fed an ethanol-containing isocaloric liquid diet for 10 wk, and the last three (the TCM group) were fed an ethanol-containing isocaloric liquid diet for 10 wk and dosed orally with TCM (222 mg/kg•d, TCM222; 667 mg/kg•d, TCM667; and 2 000 mg/kg•d, TCM2000, respectively) weekly during the last 4 wk. RESULTS: ED group developed fatty liver according to lipid profile and liver histological findings. Compared with the control group, liver/body weight, serum triglyceride (TG) and total cholesterol (TC), liver TG and TC, serum alanine aminotransferase (ALT) and aspartic aminotran-sferase (AST) significantly increased in the ED group. Whereas, in the rats administered with TCM, liver/body weight, serum TG and TC, liver TG and TC, serum ALT and AST were significantly decreased, and the degree of hepatic lipid droplets was markedly improved compared with those in the ED group. CONCLUSION: TCM treatment causes significant reduction in alcohol-induced lipid hepatic accumulation, reversing fatty liver and liver damage, and can be used as a remedy for alcoholic fatty liver. PMID:16222745

  10. Disturbances in the murine hepatic circadian clock in alcohol-induced hepatic steatosis

    PubMed Central

    Zhou, Peng; Ross, Ruth A.; Pywell, Cameron M.; Liangpunsakul, Suthat; Duffield, Giles E.

    2014-01-01

    To investigate the role of the circadian clock in the development of alcohol-induced fatty liver disease we examined livers of mice chronically alcohol-fed over 4-weeks that resulted in steatosis. Here we show time-of-day specific changes in expression of clock genes and clock-controlled genes, including those associated with lipid and bile acid regulation. Such changes were not observed following a 1-week alcohol treatment with no hepatic lipid accumulation. Real-time bioluminescence reporting of PERIOD2 protein expression suggests that these changes occur independently of the suprachiasmatic nucleus pacemaker. Further, we find profound time-of-day specific changes to the rhythmic synthesis/accumulation of triglycerides, cholesterol and bile acid, and the NAD/NADH ratio, processes that are under clock control. These results highlight not only that the circadian timekeeping system is disturbed in the alcohol-induced hepatic steatosis state, but also that the effects of alcohol upon the clock itself may actually contribute to the development of hepatic steatosis. PMID:24430730

  11. Ginger-derived nanoparticles protect against alcohol-induced liver damage.

    PubMed

    Zhuang, Xiaoying; Deng, Zhong-Bin; Mu, Jingyao; Zhang, Lifeng; Yan, Jun; Miller, Donald; Feng, Wenke; McClain, Craig J; Zhang, Huang-Ge

    2015-01-01

    Daily exposure of humans to nanoparticles from edible plants is inevitable, but significant advances are required to determine whether edible plant nanoparticles are beneficial to our health. Additionally, strategies are needed to elucidate the molecular mechanisms underlying any beneficial effects. Here, as a proof of concept, we used a mouse model to show that orally given nanoparticles isolated from ginger extracts using a sucrose gradient centrifugation procedure resulted in protecting mice against alcohol-induced liver damage. The ginger-derived nanoparticle (GDN)-mediated activation of nuclear factor erythroid 2-related factor 2 (Nrf2) led to the expression of a group of liver detoxifying/antioxidant genes and inhibited the production of reactive oxygen species, which partially contributes to the liver protection. Using lipid knock-out and knock-in strategies, we further identified that shogaol in the GDN plays a role in the induction of Nrf2 in a TLR4/TRIF-dependent manner. Given the critical role of Nrf2 in modulating numerous cellular processes, including hepatocyte homeostasis, drug metabolism, antioxidant defenses, and cell-cycle progression of liver, this finding not only opens up a new avenue for investigating GDN as a means to protect against the development of liver-related diseases such as alcohol-induced liver damage but sheds light on studying the cellular and molecular mechanisms underlying interspecies communication in the liver via edible plant-derived nanoparticles. PMID:26610593

  12. Ginger-derived nanoparticles protect against alcohol-induced liver damage

    PubMed Central

    Zhuang, Xiaoying; Deng, Zhong-Bin; Mu, Jingyao; Zhang, Lifeng; Yan, Jun; Miller, Donald; Feng, Wenke; McClain, Craig J.; Zhang, Huang-Ge

    2015-01-01

    Daily exposure of humans to nanoparticles from edible plants is inevitable, but significant advances are required to determine whether edible plant nanoparticles are beneficial to our health. Additionally, strategies are needed to elucidate the molecular mechanisms underlying any beneficial effects. Here, as a proof of concept, we used a mouse model to show that orally given nanoparticles isolated from ginger extracts using a sucrose gradient centrifugation procedure resulted in protecting mice against alcohol-induced liver damage. The ginger-derived nanoparticle (GDN)–mediated activation of nuclear factor erythroid 2-related factor 2 (Nrf2) led to the expression of a group of liver detoxifying/antioxidant genes and inhibited the production of reactive oxygen species, which partially contributes to the liver protection. Using lipid knock-out and knock-in strategies, we further identified that shogaol in the GDN plays a role in the induction of Nrf2 in a TLR4/TRIF-dependent manner. Given the critical role of Nrf2 in modulating numerous cellular processes, including hepatocyte homeostasis, drug metabolism, antioxidant defenses, and cell-cycle progression of liver, this finding not only opens up a new avenue for investigating GDN as a means to protect against the development of liver-related diseases such as alcohol-induced liver damage but sheds light on studying the cellular and molecular mechanisms underlying interspecies communication in the liver via edible plant–derived nanoparticles. PMID:26610593

  13. Advances and New Concepts in Alcohol-Induced Organelle Stress, Unfolded Protein Responses and Organ Damage

    PubMed Central

    Ji, Cheng

    2015-01-01

    Alcohol is a simple and consumable biomolecule yet its excessive consumption disturbs numerous biological pathways damaging nearly all organs of the human body. One of the essential biological processes affected by the harmful effects of alcohol is proteostasis, which regulates the balance between biogenesis and turnover of proteins within and outside the cell. A significant amount of published evidence indicates that alcohol and its metabolites directly or indirectly interfere with protein homeostasis in the endoplasmic reticulum (ER) causing an accumulation of unfolded or misfolded proteins, which triggers the unfolded protein response (UPR) leading to either restoration of homeostasis or cell death, inflammation and other pathologies under severe and chronic alcohol conditions. The UPR senses the abnormal protein accumulation and activates transcription factors that regulate nuclear transcription of genes related to ER function. Similarly, this kind of protein stress response can occur in other cellular organelles, which is an evolving field of interest. Here, I review recent advances in the alcohol-induced ER stress response as well as discuss new concepts on alcohol-induced mitochondrial, Golgi and lysosomal stress responses and injuries. PMID:26047032

  14. Potential Role of the Gut/Liver/Lung Axis in Alcohol-Induced Tissue Pathology

    PubMed Central

    Massey, Veronica L.; Beier, Juliane I.; Ritzenthaler, Jeffrey D.; Roman, Jesse; Arteel, Gavin E.

    2015-01-01

    Both Alcoholic Liver Disease (ALD) and alcohol-related susceptibility to acute lung injury are estimated to account for the highest morbidity and mortality related to chronic alcohol abuse and, thus, represent a focus of intense investigation. In general, alcohol-induced derangements to both organs are considered to be independent and are often evaluated separately. However, the liver and lung share many general responses to damage, and specific responses to alcohol exposure. For example, both organs possess resident macrophages that play key roles in mediating the immune/inflammatory response. Additionally, alcohol-induced damage to both organs appears to involve oxidative stress that favors tissue injury. Another mechanism that appears to be shared between the organs is that inflammatory injury to both organs is enhanced by alcohol exposure. Lastly, altered extracellular matrix (ECM) deposition appears to be a key step in disease progression in both organs. Indeed, recent studies suggest that early subtle changes in the ECM may predispose the target organ to an inflammatory insult. The purpose of this chapter is to review the parallel mechanisms of liver and lung injury in response to alcohol consumption. This chapter will also explore the potential that these mechanisms are interdependent, as part of a gut-liver-lung axis. PMID:26437442

  15. Modulatory role of Emblica officinalis against alcohol induced biochemical and biophysical changes in rat erythrocyte membranes.

    PubMed

    Reddy, Vaddi Damodara; Padmavathi, Pannuru; Paramahamsa, Maturu; Varadacharyulu, Nallanchakravarthula

    2009-08-01

    This study investigated the protective effect of Emblica officinalis against alcohol-induced biochemical and biophysical changes in rat erythrocyte membranes. Thirty-two male rats were divided into four groups (n=8 in each group): control (C), alcohol (A), alcohol plus Emblica fruit extract (A+EFE) and Emblica fruit extract (EFE) alone. Administration of twenty percent alcohol (5 g/kg body weight) to rats significantly increased cholesterol/phospholipid (C/P) ratio, lipid peroxidation and the activities of Na(+)/K(+) and Mg(2+) ATPases in erythrocyte membranes as well as augmented nitric oxide (NO) levels. However, membrane fluidity studies using the fluorescent probe DPH (1,6 diphenyl 1,3 hexatriene) reveals that alcohol administration significantly (p<0.05) increased membrane anisotropic values and altered membrane individual phospholipid content. Administration of EFE (250 mg/kg body weight) to alcoholic rats resulted in significant (p<0.05) reduction of NO levels, erythrocyte membrane lipid peroxidation, C/P ratio, activities of Na(+)/K(+) and Mg(2+) ATPases and fluorescent anisotropic values. Further, EFE administration to alcoholic rats beneficially modulated membrane properties as evidenced from the contents of total phospholipids as well individual phospholipid classes. The tannoid principles present in Emblica offers protection against alcohol induced adverse effects in rats. PMID:19454300

  16. Effectiveness of artichoke extract in preventing alcohol-induced hangovers: a randomized controlled trial

    PubMed Central

    Pittler, Max H.; White, Adrian R.; Stevinson, Clare; Ernst, Edzard

    2003-01-01

    Background Extract of globe artichoke (Cynara scolymus) is promoted as a possible preventive or cure for alcohol-induced hangover symptoms. However, few rigorous clinical trials have assessed the effects of artichoke extract, and none has examined the effects in relation to hangovers. We undertook this study to test whether artichoke extract is effective in preventing the signs and symptoms of alcohol-induced hangover. Methods We recruited healthy adult volunteers between 18 and 65 years of age to participate in a randomized double-blind crossover trial. Participants received either 3 capsules of commercially available standardized artichoke extract or indistinguishable, inert placebo capsules immediately before and after alcohol exposure. After a 1-week washout period the volunteers received the opposite treatment. Participants predefined the type and amount of alcoholic beverage that would give them a hangover and ate the same meal before commencing alcohol consumption on the 2 study days. The primary outcome measure was the difference in hangover severity scores between the artichoke extract and placebo interventions. Secondary outcome measures were differences between the interventions in scores using a mood profile questionnaire and cognitive performance tests administered 1 hour before and 10 hours after alcohol exposure. Results Fifteen volunteers participated in the study. The mean number (and standard deviation) of alcohol units (each unit being 7.9 g, or 10 mL, of ethanol) consumed during treatment with artichoke extract and placebo was 10.7 (3.1) and 10.5 (2.4) respectively, equivalent to 1.2 (0.3) and 1.2 (0.2) g of alcohol per kilogram body weight. The volume of nonalcoholic drink consumed and the duration of sleep were similar during the artichoke extract and placebo interventions. None of the outcome measures differed significantly between interventions. Adverse events were rare and were mild and transient. Interpretation Our results suggest that

  17. Alcohol-Induced Changes in Opioid Peptide Levels in Adolescent Rats Are Dependent on Housing Conditions

    PubMed Central

    Palm, Sara; Nylander, Ingrid

    2014-01-01

    Background Endogenous opioids are implicated in the mechanism of action of alcohol and alcohol affects opioids in a number of brain areas, although little is known about alcohol's effects on opioids in the adolescent brain. One concern, in particular when studying young animals, is that alcohol intake models often are based on single housing that may result in alcohol effects confounded by the lack of social interactions. The aim of this study was to investigate short- and long-term alcohol effects on opioids and the influence of housing conditions on these effects. Methods In the first part, opioid peptide levels were measured after one 24-hour session of single housing and 2-hour voluntary alcohol intake in adolescent and adult rats. In the second part, a model with a cage divider inserted during 2-hour drinking sessions was tested and the effects on opioids were examined after 6 weeks of adolescent voluntary intake in single-and pair-housed rats, respectively. Results The effects of single housing were age specific and affected Met-enkephalin-Arg6Phe7 (MEAP) in particular. In adolescent rats, it was difficult to distinguish between effects induced by alcohol and single housing, whereas alcohol-specific effects were seen in dynorphin B (DYNB), beta-endorphin (BEND), and MEAP levels in adults. Voluntary drinking affected several brain areas and the majority of alcohol-induced effects were not dependent on housing. However, alcohol effects on DYNB and BEND in the amygdala were dependent on housing. Housing alone affected MEAP in the cingulate cortex. Conclusions Age-specific housing- and alcohol-induced effects on opioids were found. In addition, prolonged voluntary alcohol intake under different housing conditions produced several alcohol-induced effects independent of housing. However, housing-dependent effects were found in areas implicated in stress, emotionality, and alcohol use disorder. Housing condition and age may therefore affect the reasons and

  18. A Mechanistic Review of Cell Death in Alcohol-Induced Liver Injury.

    PubMed

    Wang, Shaogui; Pacher, Pal; De Lisle, Robert C; Huang, Heqing; Ding, Wen-Xing

    2016-06-01

    Alcoholic liver disease (ALD) is a major health problem in the United States and worldwide without successful treatments. Chronic alcohol consumption can lead to ALD, which is characterized by steatosis, inflammation, fibrosis, cirrhosis, and even liver cancer. Recent studies suggest that alcohol induces both cell death and adaptive cell survival pathways in the liver, and the balance of cell death and cell survival ultimately decides the pathogenesis of ALD. This review summarizes the recent progress on the role and mechanisms of apoptosis, necroptosis, and autophagy in the pathogenesis of ALD. Understanding the complex regulation of apoptosis, necrosis, and autophagy may help to develop novel therapeutic strategies by targeting all 3 pathways simultaneously. PMID:27130888

  19. Analysis of alcohol-induced DNA damage in Escherichia coli by visualizing single genomic DNA molecules.

    PubMed

    Kang, Yujin; Lee, Jinyong; Kim, Jisoo; Oh, Yeeun; Kim, Dogeun; Lee, Jungyun; Lim, Sangyong; Jo, Kyubong

    2016-07-21

    Consumption of alcohol injures DNA, and such damage is considered to be a primary cause for the development of cancer and many other diseases essentially due to reactive oxygen species generated from alcohol. To sensitively detect alcohol-induced DNA lesions in a biological system, we introduced a novel analytical platform for visualization of single genomic DNA molecules using E. coli. By fluorescently labelling the DNA lesions, our approach demonstrated, with the highest sensitivity, that we could count the number of DNA lesions induced by alcohol metabolism in a single bacterial cell. Moreover, our results showed a linear relationship between ethanol concentration and the number of DNA lesions: 0.88 lesions per 1% ethanol. Using this approach, we quantitatively analysed the DNA damage induced by exposure to alcoholic beverages such as beer (5% ethanol), rice wine (13%), soju (20%), and whisky (40%). PMID:27186604

  20. Role of MCP-1 in alcohol-induced aggressiveness of colorectal cancer cells.

    PubMed

    Xu, Mei; Wang, Siying; Qi, Yuanlin; Chen, Li; Frank, Jacqueline A; Yang, Xiuwei H; Zhang, Zhuo; Shi, Xianglin; Luo, Jia

    2016-05-01

    Epidemiological studies demonstrate that alcohol consumption is associated with an increased risk of colorectal cancer (CRC). In addition to promoting carcinogenesis, alcohol may also accelerate the progression of existing CRC. We hypothesized that alcohol may enhance the aggressiveness of CRC. In this study, we investigated the effect of alcohol on the migration/invasion and metastasis of CRC. Alcohol increased the migration/invasion of colorectal cancer cells (DLD1, HCT116, HT29, and SW480) in a concentration-dependent manner. Among these colon cancer cell lines, HCT116 cells were most responsive while HT29 cells were the least responsive to ethanol-stimulated cell migration/invasion. These in vitro results were supported by animal studies which demonstrated that ethanol enhanced the metastasis of colorectal cancer cells to the liver and lung. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that plays an important role in regulating tumor microenvironment and metastasis. Alcohol increased the expression of MCP-1 and its receptor CCR2 at both protein and mRNA levels. The pattern of alcohol-induced alterations in MCP-1 expression was consistent with its effect on migration/invasion; HCT116 cells displayed the highest up-regulation of MCP-1/CCR2 in response to alcohol exposure. An antagonist of CCR2 blocked alcohol-stimulated migration. Alcohol caused an initial cytosolic accumulation of β-catenin and its subsequent nuclear translocation by inhibiting GSK3β activity. Alcohol stimulated the activity of MCP-1 gene promoter in a β-catenin-dependent manner. Furthermore, knock-down of MCP-1/CCR2 or β-catenin was sufficient to inhibit alcohol-induced cell migration/invasion. Together, these results suggested that alcohol may promote the metastasis of CRC through modulating GSK3β/β-catenin/MCP-1 pathway. © 2015 Wiley Periodicals, Inc. PMID:26014148

  1. Deletion of tumor progression locus 2 attenuates alcohol-induced hepatic inflammation

    PubMed Central

    Stice, Camilla P.; Hussain, Sajid; Liu, Chun; Ausman, Lynne M.

    2016-01-01

    Background The pathogenesis of alcoholic liver disease (ALD) involves the interaction of several inflammatory signaling pathways. Tumor progression locus 2 (TPL2), also known as Cancer Osaka Thyroid (COT) and MAP3K8, is a serine-threonine kinase that functions as a critical regulator of inflammatory pathways by up-regulating production of inflammatory cytokines. The present study aims to fill the gap in knowledge regarding the involvement of TPL2 in the mechanism of alcohol-induced hepatic inflammation. Methods Male TPL2−/− knockout (TPL2KO) mice and TPL2+/+ wild-type (WT) mice were group pair-fed with Lieber-DeCarli liquid ethanol diet (EtOH diet, 27% energy from EtOH) or control diet (ctrl diet) for 4 weeks. Both histological and molecular biomarkers involved in the induction of hepatic inflammation by alcohol consumption were examined. Results Consumption of the EtOH diet in WT mice lead to a significant induction of TPL2 mRNA expression as compared with WT mice fed ctrl diet. A significant induction in inflammatory foci and steatosis was also observed in WT mice fed EtOH diet. The deletion of TPL2 significantly reduced inflammatory foci in the liver of mice consuming both ctrl and EtOH diets as compared to their respective WT controls. This reduction was associated with suppression of hepatic inflammatory gene expression of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) and macrophage marker F4/80. In addition, histological analysis of livers revealed that TPL2 deletion resulted in reduced steatosis in both ctrl (significant) and EtOH (non-significant) diet-fed mice as compared to their respective WT controls. Conclusions The demonstration that TPL2 deletion attenuates alcohol-induced hepatic inflammation provides evidence of a novel role for TPL2 in the pathogenesis of ALD. PMID:26904554

  2. Endothelial Nitric Oxide Mediates Caffeine Antagonism of Alcohol-Induced Cerebral Artery Constriction.

    PubMed

    Chang, Jennifer; Fedinec, Alexander L; Kuntamallappanavar, Guruprasad; Leffler, Charles W; Bukiya, Anna N; Dopico, Alex M

    2016-01-01

    Despite preventive education, the combined consumption of alcohol and caffeine (particularly from "energy drinks") continues to rise. Physiologic perturbations by separate intake of ethanol and caffeine have been widely documented. However, the biologic actions of the alcohol-caffeine combination and their underlying subcellular mechanisms have been scarcely studied. Using intravital microscopy on a closed-cranial window and isolated, pressurized vessels, we investigated the in vivo and in vitro action of ethanol-caffeine mixtures on cerebral arteries from rats and mice, widely recognized models to address cerebrovascular pathophysiology and pharmacology. Caffeine at concentrations found in human circulation after ingestion of one to two cups of coffee (10 µM) antagonized the endothelium-independent constriction of cerebral arteries evoked by ethanol concentrations found in blood during moderate-heavy alcohol intoxication (40-70 mM). Caffeine antagonism against alcohol was similar whether evaluated in vivo or in vitro, suggesting independence of systemic factors and drug metabolism, but required a functional endothelium. Moreover, caffeine protection against alcohol increased nitric oxide (NO•) levels over those found in the presence of ethanol alone, disappeared upon blocking NO• synthase, and could not be detected in pressurized cerebral arteries from endothelial nitric-oxide synthase knockout (eNOS(-/-)) mice. Finally, incubation of de-endothelialized cerebral arteries with the NO• donor sodium nitroprusside (10 µM) fully restored the protective effect of caffeine. This study demonstrates for the first time that caffeine antagonizes ethanol-induced cerebral artery constriction and identifies endothelial NO• as the critical caffeine effector on smooth muscle targets. Conceivably, situations that perturb endothelial function and/or NO• availability will critically alter caffeine antagonism of alcohol-induced cerebrovascular constriction without

  3. Aging accentuates alcohol-induced decrease in protein synthesis in gastrocnemius.

    PubMed

    Korzick, Donna H; Sharda, Daniel R; Pruznak, Anne M; Lang, Charles H

    2013-05-15

    The present study sought to determine whether the protein catabolic response in skeletal muscle produced by chronic alcohol feeding was exaggerated in aged rats. Adult (3 mo) and aged (18 mo) female F344 rats were fed a nutritionally complete liquid diet containing alcohol (36% of total calories) or an isocaloric isonitrogenous control diet for 20 wk. Muscle (gastrocnemius) protein synthesis, as well as mTOR and proteasome activity did not differ between control-fed adult and aged rats, despite the increased TNF-α and IL-6 mRNA and decreased IGF-I mRNA in muscle of aged rats. Compared with alcohol-fed adult rats, aged rats demonstrated an exaggerated alcohol-induced reduction in lean body mass and protein synthesis (both sarcoplasmic and myofibrillar) in gastrocnemius. Alcohol-fed aged rats had enhanced dephosphorylation of 4E-BP1, as well as enhanced binding of raptor with both mTOR and Deptor, and a decreased binding of raptor with 4E-BP1. Alcohol feeding of both adult and aged rats reduced RagA binding to raptor. The LKB1-AMPK-REDD1 pathway was upregulated in gastrocnemius from alcohol-fed aged rats. These exaggerated alcohol-induced effects in aged rats were associated with a greater decrease in muscle but not circulating IGF-I, but no further increase in inflammatory mediators. In contrast, alcohol did not exaggerate the age-induced increase in atrogin-1 and MuRF1 mRNA or the increased proteasome activity. Our results demonstrate that, compared with adult rats, the gastrocnemius from aged rats is more sensitive to the catabolic effects of alcohol on protein synthesis, but not protein degradation, and this exaggerated response may be AMPK-dependent. PMID:23535459

  4. Intestinal Malrotation

    MedlinePlus

    ... the intestines don't position themselves normally during fetal development and aren't attached inside properly as a result. The exact reason this occurs is unknown. When a fetus develops in the womb, the intestines start out ...

  5. Intestinal obstruction

    MedlinePlus

    ... of the major causes of intestinal obstruction in infants and children. Causes of paralytic ileus may include: Bacteria or viruses that cause intestinal infections ( gastroenteritis ) Chemical, electrolyte, or mineral imbalances (such as decreased ...

  6. Undernutrition Enhances Alcohol-Induced Hepatocyte Proliferation in the Liver of Rats Fed Via Total Enteral Nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To assess the relative contributions of undernutrition and ethanol (EtOH) exposure to alcohol-induced hepatotoxicity, female Sprague-Dawley rats were intragastrically infused liquid diets containing 187 kcal/kg3/4/day or 154 kcal/kg3/4/day, with or without 11 g/kg/day EtOH. EtOH clearance was impai...

  7. Intestine Transplant

    MedlinePlus

    ... intestine segment, most intestine transplants involve a whole organ from a deceased donor. In addition, most intestine transplants are performed in ... blood before surgery. I am looking for ... allocation About UNOS Being a living donor Calculator - CPRA Calculator - KDPI Calculator - LAS Calculator - MELD ...

  8. Apoptosis, Necrosis, and Necroptosis in the Gut and Intestinal Homeostasis

    PubMed Central

    Negroni, Anna; Cucchiara, Salvatore; Stronati, Laura

    2015-01-01

    Intestinal epithelial cells (IECs) form a physiochemical barrier that separates the intestinal lumen from the host's internal milieu and is critical for electrolyte passage, nutrient absorption, and interaction with commensal microbiota. Moreover, IECs are strongly involved in the intestinal mucosal inflammatory response as well as in mucosal innate and adaptive immune responses. Cell death in the intestinal barrier is finely controlled, since alterations may lead to severe disorders, including inflammatory diseases. The emerging picture indicates that intestinal epithelial cell death is strictly related to the maintenance of tissue homeostasis. This review is focused on previous reports on different forms of cell death in intestinal epithelium. PMID:26483605

  9. Autophagy and Intestinal Homeostasis

    PubMed Central

    Patel, Khushbu K.; Stappenbeck, Thaddeus S.

    2013-01-01

    Nutrient absorption is the basic function that drives mammalian intestinal biology. To facilitate nutrient uptake, the host’s epithelial barrier is composed of a single layer of cells. This constraint is problematic, as a design of this type can be easily disrupted. The solution during the course of evolution was to add numerous host defense mechanisms that can help prevent local and systemic infection. These mechanisms include specialized epithelial cells that produce a physiochemical barrier overlying the cellular barrier, robust and organized adaptive and innate immune cells, and the ability to mount an inflammatory response that is commensurate with a specific threat level. The autophagy pathway is a critical cellular process that strongly influences all these functions. Therefore, a fundamental understanding of the components of this pathway and their influence on inflammation, immunity, and barrier function will facilitate our understanding of homeostasis in the gastrointestinal tract. PMID:23216414

  10. Autophagy and intestinal homeostasis.

    PubMed

    Patel, Khushbu K; Stappenbeck, Thaddeus S

    2013-01-01

    Nutrient absorption is the basic function that drives mammalian intestinal biology. To facilitate nutrient uptake, the host's epithelial barrier is composed of a single layer of cells. This constraint is problematic, as a design of this type can be easily disrupted. The solution during the course of evolution was to add numerous host defense mechanisms that can help prevent local and systemic infection. These mechanisms include specialized epithelial cells that produce a physiochemical barrier overlying the cellular barrier, robust and organized adaptive and innate immune cells, and the ability to mount an inflammatory response that is commensurate with a specific threat level. The autophagy pathway is a critical cellular process that strongly influences all these functions. Therefore, a fundamental understanding of the components of this pathway and their influence on inflammation, immunity, and barrier function will facilitate our understanding of homeostasis in the gastrointestinal tract. PMID:23216414

  11. Oral administration of fermented wild ginseng ameliorates DSS-induced acute colitis by inhibiting NF-κB signaling and protects intestinal epithelial barrier

    PubMed Central

    Seong, Myeong A; Woo, Jong Kyu; Kang, Ju-Hee; Jang, Yeong Su; Choi, Seungho; Jang, Young Saeng; Lee, Taek Hwan; Jung, Kyung Hoon; Kang, Dong Kyu; Hurh, Byung Seok; Kim, Dae Eung; Kim, Sun Yeou; Oh, Seung Hyun

    2015-01-01

    Ginseng has been widely used for therapeutic and preventive purposes for thousands of years. However, orally administered ginseng has very low bioavailability and absorption in the intestine. Therefore, fermented ginseng was developed to enhance the beneficial effects of ginseng in the intestine. In this study, we investigated the molecular mechanisms underlying the anti-inflammatory activity of fermented wild ginseng (FWG). We found that FWG significantly alleviated the severity of colitis in a dextran sodium sulfate (DSS)-induced colitis mouse model, and decreased expression level of pro-inflammatory cytokines in colonic tissue. Moreover, we observed that FWG suppressed the infiltration of macrophages in DSS-induced colitis. FWG also attenuated the transcriptional activity of nuclear factor-κB (NF-κB) by reducing the translocation of NF-κB into the nucleus. Our data indicate that FWG contains anti-inflammatory activity via NF-κB inactivation and could be useful for treating colitis. [BMB Reports 2015; 48(7): 419-425] PMID:25936779

  12. Beneficial effects of chlorogenic acid on alcohol-induced damage in PC12 cells.

    PubMed

    Fang, Shi-Qi; Wang, Yong-Tang; Wei, Jing-Xiang; Shu, Ya-Hai; Xiao, Lan; Lu, Xiu-Min

    2016-04-01

    As one of the most commonly abused psychotropic substances, ethanol exposure has deleterious effects on the central nervous system (CNS). The most detrimental results of ethanol exposure during development are the loss of neurons in brain regions such as the hippocampus and neocortex, which may be related to the apoptosis and necrosis mediated by oxidative stress. Recent studies indicated that a number of natural drugs from plants play an important role in protection of nerve cells from damage. Among these, it has been reported that chlorogenic acid (CA) has neuroprotective effects against oxidative stress. Thus, it may play some beneficial effects on ethanol-induced neurotoxicity. However, the effects of CA on ethanol-induced nerve damage remain unclear. In order to investigate the protective effects of CA on alcohol-induced apoptosis in rat pheochromocytoma PC12 cells, in the present study, cell viability and the optimal dosage of CA were first quantified by MTT assay. Then, the cell apoptosis and cell cycle were respectively investigated by Hoechst 33258 staining and flow cytometer (FCM). To further clarify the possible mechanism, followed with the test of mitochondria transmembrane potential with Rhodamine 123 (Rho 123) staining, the expression of Bcl-2, Capase-3 and growth associated protein-43 (GAP-43) were analyzed by immunofluorescence assay separately. The results showed that treatment with 500mM alcohol decreased the cell viability and then significantly induced apoptosis in PC12 cells. However, when pretreated with different concentrations of CA (1, 5, 10, 50μM), cell viability increased in different degree. Comparatively, CA with the concentration of 10μM most effectively promoted the proliferation of damaged cells, increased the distribution ratio of the cells at the G2/M and S phases, and enhanced mitochondria transmembrane potential. This appears to be in agreement with up-regulation of the expression of Bcl-2 and GAP-43, and down-regulation of the

  13. Drinking habits as cofactors of risk for alcohol induced liver damage

    PubMed Central

    Bellentani, S; Saccoccio, G; Costa, G; Tiribelli, C; Manenti, F; Sodde, M; Croce', L; Sasso, F; Pozzato, G; Cristianini, G; a Brandi

    1997-01-01

    Background—The Dionysos Study is a cohort study of the prevalence of chronic liver disease in the general population of two northern Italian communities. It included 6917 subjects, aged 12-65 (69% of the total population). 
Aims—The aim of this part of the study was to examine the relationship of daily alcohol intake, type of alcoholic beverage consumed, and drinking patterns to the presence of alcohol induced liver damage in an open population. 
Patients and methods—6534 subjects, free of virus related chronic liver disease and participating in the first cross-sectional part of the study, were fully examined. Each subject underwent: (a) medical history and physical examination, (b) evaluation of alcohol intake using an illustrated dietary questionnaire, and (c) routine blood tests. More invasive diagnostic procedures were performed when indicated. 
Results—Multivariate analysis showed that the risk threshold for developing either cirrhosis or non-cirrhotic liver damage (NCLD) was ingestion of more than 30 g alcohol per day in both sexes. Using this definition, 1349 individuals (21% of the population studied) were at risk. Of these, only 74 (5.5% of the individuals at risk) showed signs of liver damage. The prevalence of "pure" alcoholic cirrhosis was 0.43% (30 of 6917), representing 2.2% of the individuals at risk, with a ratio of men to women of 9:1, while 44 (3.3% of the individuals at risk) showed persistent signs of NCLD. After 50 years of age, the cumulative risk of developing both NCLD and cirrhosis was significantly higher (p<0.0001) for those individuals who regularly drank alcohol both with and without food than for those who drank only at mealtimes. 
Conclusions—Our data show that in an open population the risk threshold for developing cirrhosis and NCLD is 30 g ethanol/day, and this risk increases with increasing daily intake. Drinking alcohol outside mealtimes and drinking multiple different alcoholic beverages both increase the risk

  14. DESIPRAMINE BLOCKS ALCOHOL-INDUCED ANXIETY- AND DEPRESSIVE-LIKE BEHAVIORS IN TWO RAT STRAINS

    PubMed Central

    GETACHEW, BRUK; HAUSER, SHEKETHA R.; TAYLOR, ROBERT E.; TIZABI, YOUSEF

    2011-01-01

    Epidemiological studies indicate significant co-morbid expression of alcoholism, anxiety, and depression. These symptoms are often under-diagnosed and under-treated and can worsen prognostic and treatment outcome for alcoholism. Nonetheless, a causal relationship between alcoholism and these conditions is yet to be established. In this study we sought to determine the effects of daily alcohol administration on the indices of anxiety and depression in two rat strains, one of which exhibits inherent depressive-like characteristics. Moreover, it was of relevance to examine the effects of a clinically useful antidepressant on alcohol-induced behavioral changes. Wistar-Kyoto (WKY) rats derived from Wistar stock show low levels of locomotor activity in an open field and high levels of immobility in the forced swim test (FST) which is considered a measure of their helplessness and hence are considered a putative animal model of depression. Adult female WKY and Wistar rats were exposed for 3 hrs daily to 95% ethanol vapor to achieve a mean blood alcohol level (BAL) of approximately 150 mg/dL. Controls were exposed to air in similar inhalation chambers. Sixteen to 18 hrs following 7 or 14 days of exposure to alcohol, locomotor activity (LCA) in open field, duration of time spent in the open arm of the elevated plus-maze (EPM), reflective of anxiety-like behavior and immobility in FST were evaluated. Alcohol exposure for 7 or 14 days reduced LCA only in Wistar rats but enhanced FST immobility in both strains at both time points. Only 14 day alcohol exposure reduced EPM open arm time in both WKY and Wistar rats. Daily treatment with desipramine (8 mg/kg) blocked all the changes induced by alcohol in both strains. Thus, subchronic (7 day) exposure to alcohol induces depressive-like characteristics in Wistar rats and exacerbates that of WKY rats. Chronic (14 day) exposure, however, also induces an anxiety-like effect in both strains. The depressive-and anxiety-like behaviors

  15. Alcohol-induced IL-1β in the brain is mediated by NLRP3/ASC inflammasome activation that amplifies neuroinflammation

    PubMed Central

    Lippai, Dora; Bala, Shashi; Petrasek, Jan; Csak, Timea; Levin, Ivan; Kurt-Jones, Evelyn A.; Szabo, Gyongyi

    2013-01-01

    Alcohol-induced neuroinflammation is mediated by proinflammatory cytokines, including IL-1β. IL-1β production requires caspase-1 activation by inflammasomes—multiprotein complexes that are assembled in response to danger signals. We hypothesized that alcohol-induced inflammasome activation contributes to increased IL-1β in the brain. WT and TLR4-, NLRP3-, and ASC-deficient (KO) mice received an ethanol-containing or isocaloric control diet for 5 weeks, and some received the rIL-1ra, anakinra, or saline treatment. Inflammasome activation, proinflammatory cytokines, endotoxin, and HMGB1 were measured in the cerebellum. Expression of inflammasome components (NLRP1, NLRP3, ASC) and proinflammatory cytokines (TNF-α, MCP-1) was increased in brains of alcohol-fed compared with control mice. Increased caspase-1 activity and IL-1β protein in ethanol-fed mice indicated inflammasome activation. TLR4 deficiency protected from TNF-α, MCP-1, and attenuated alcohol-induced IL-1β increases. The TLR4 ligand, LPS, was not increased in the cerebellum. However, we found up-regulation of acetylated and phosphorylated HMGB1 and increased expression of the HMGB1 receptors (TLR2, TLR4, TLR9, RAGE) in alcohol-fed mice. NLRP3- or ASC-deficient mice were protected from caspase-1 activation and alcohol-induced IL-1β increase in the brain. Furthermore, in vivo treatment with rIL-1ra prevented alcohol-induced inflammasome activation and IL-1β, TNF-α, and acetylated HMGB1 increases in the cerebellum. Conversely, intracranial IL-1β administration induced TNF-α and MCP-1 in the cerebellum. In conclusion, alcohol up-regulates and activates the NLRP3/ASC inflammasome, leading to caspase-1 activation and IL-1β increase in the cerebellum. IL-1β amplifies neuroinflammation, and disruption of IL-1/IL-1R signaling prevents alcohol-induced inflammasome activation and neuroinflammation. Increased levels of acetylated and phosphorylated HMGB1 may contribute to alcoholic neuroinflammation

  16. Intestinal transplantation.

    PubMed

    Rege, Aparna; Sudan, Debra

    2016-04-01

    Intestinal transplantation has now emerged as a lifesaving therapeutic option and standard of care for patients with irreversible intestinal failure. Improvement in survival over the years has justified expansion of the indications for intestinal transplantation beyond the original indications approved by Center for Medicare and Medicaid services. Management of patients with intestinal failure is complex and requires a multidisciplinary approach to accurately select candidates who would benefit from rehabilitation versus transplantation. Significant strides have been made in patient and graft survival with several advancements in the perioperative management through timely referral, improved patient selection, refinement in the surgical techniques and better understanding of the immunopathology of intestinal transplantation. The therapeutic efficacy of the procedure is well evident from continuous improvements in functional status, quality of life and cost-effectiveness of the procedure. This current review summarizes various aspects including current practices and evidence based recommendations of intestinal transplantation. PMID:27086894

  17. INTESTINAL TRANSPLANTATION

    PubMed Central

    Tzakis, Andreas G.; Todo, Satoru; Starzl, Thomas E.

    2010-01-01

    Intestinal transplantation is often the only alternative form of treatment for patients dependent on total parenteral nutrition for survival. Although a limited number of intestinal transplantations have been performed, results with FK 506 immunosuppression are comparable to those for other organ transplants. The impact of successful intestinal transplantation on gastroenterology will likely be similar to the impact of kidney and liver transplantation on nephrology and hepatology. PMID:7515221

  18. An introduction to alcohol-induced brain damage and its causes.

    PubMed

    Harper, C; Kril, J

    1994-01-01

    The aim of the symposium on alcohol-induced brain damage is to review current opinion and recent advances concerning factors which are thought to play a significant role in this disorder. The three principal factors are: alcohol specific neurotoxicity, associated vitamin B1 (thiamine) deficiency (the Wernicke-Korsakoff syndrome) and liver failure secondary to alcoholic cirrhosis. There is a complex interaction of these and other factors and it is difficult to dissect out the relative importance of each in the pathogenesis of alcohol-related brain damage. Moreover recent molecular and biochemical studies suggest that several of these factors may have pathogenetic mechanisms in common-for example, excitotoxicity, mitric oxide and free radicals. The application of new technologies in neuropathological studies of carefully selected groups of alcoholic cases is beginning to reveal a far more complex pattern of damage than current view holds. Quantitative morphometry and immunohistochemistry can be combined to create three dimensional images of various anatomical regions of the brain together with detailed analyses of neuronal counts, sizes and neurochemical type. In the Wernicke-Korsakoff syndrome (WKS) there is good evidence (in support of neuropsychological and neuroradiological data) to suggest that specific populations of neurons are damaged in cortical and subcortical regions. In those cases with the WKS there is also evidence of pathological damage in cortical and subcortical regions other than the well described periventricular distributions. These more detailed studies provide us with a more comprehensive understanding of alcohol-related brain damage. PMID:8974342

  19. Prior Binge Ethanol Exposure Potentiates the Microglial Response in a Model of Alcohol-Induced Neurodegeneration

    PubMed Central

    Marshall, Simon Alex; Geil, Chelsea Rhea; Nixon, Kimberly

    2016-01-01

    Excessive alcohol consumption results in neurodegeneration which some hypothesize is caused by neuroinflammation. One characteristic of neuroinflammation is microglial activation, but it is now well accepted that microglial activation may be pro- or anti-inflammatory. Recent work indicates that the Majchrowicz model of alcohol-induced neurodegeneration results in anti-inflammatory microglia, while intermittent exposure models with lower doses and blood alcohol levels produce microglia with a pro-inflammatory phenotype. To determine the effect of a repeated binge alcohol exposure, rats received two cycles of the four-day Majchrowicz model. One hemisphere was then used to assess microglia via immunohistochemistry and while the other was used for ELISAs of cytokines and growth factors. A single binge ethanol exposure resulted in low-level of microglial activation; however, a second binge potentiated the microglial response. Specifically, double binge rats had greater OX-42 immunoreactivity, increased ionized calcium-binding adapter molecule 1 (Iba-1+) cells, and upregulated tumor necrosis factor-α (TNF-α) compared with the single binge ethanol group. These data indicate that prior ethanol exposure potentiates a subsequent microglia response, which suggests that the initial exposure to alcohol primes microglia. In summary, repeated ethanol exposure, independent of other immune modulatory events, potentiates microglial activity. PMID:27240410

  20. Were James Bond’s drinks shaken because of alcohol induced tremor?

    PubMed Central

    Johnson, Graham; Guha, Indra Neil

    2013-01-01

    Objective To quantify James Bond’s consumption of alcohol as detailed in the series of novels by Ian Fleming. Design Retrospective literature review. Setting The study authors’ homes, in a comfy chair. Participants Commander James Bond, 007; Mr Ian Lancaster Fleming. Main outcome measures Weekly alcohol consumption by Commander Bond. Methods All 14 James Bond books were read by two of the authors. Contemporaneous notes were taken detailing every alcoholic drink taken. Predefined alcohol unit levels were used to calculate consumption. Days when Bond was unable to consume alcohol (such as through incarceration) were noted. Results After exclusion of days when Bond was unable to drink, his weekly alcohol consumption was 92 units a week, over four times the recommended amount. His maximum daily consumption was 49.8 units. He had only 12.5 alcohol free days out of 87.5 days on which he was able to drink. Conclusions James Bond’s level of alcohol intake puts him at high risk of multiple alcohol related diseases and an early death. The level of functioning as displayed in the books is inconsistent with the physical, mental, and indeed sexual functioning expected from someone drinking this much alcohol. We advise an immediate referral for further assessment and treatment, a reduction in alcohol consumption to safe levels, and suspect that the famous catchphrase “shaken, not stirred” could be because of alcohol induced tremor affecting his hands. PMID:24336307

  1. Differential Sensitivity of Prefrontal Cortex and Hippocampus to Alcohol-Induced Toxicity

    PubMed Central

    Fowler, Anna-Kate; Thompson, Jeremy; Chen, Lixia; Dagda, Marisela; Dertien, Janet; Dossou, Katina Sylvestre S.; Moaddel, Ruin; Bergeson, Susan E.; Kruman, Inna I.

    2014-01-01

    The prefrontal cortex (PFC) is a brain region responsible for executive functions including working memory, impulse control and decision making. The loss of these functions may ultimately lead to addiction. Using histological analysis combined with stereological technique, we demonstrated that the PFC is more vulnerable to chronic alcohol-induced oxidative stress and neuronal cell death than the hippocampus. This increased vulnerability is evidenced by elevated oxidative stress-induced DNA damage and enhanced expression of apoptotic markers in PFC neurons. We also found that one-carbon metabolism (OCM) impairment plays a significant role in alcohol toxicity to the PFC seen from the difference in the effects of acute and chronic alcohol exposure on DNA repair and from exaggeration of the damaging effects upon additional OCM impairment in mice deficient in a key OCM enzyme, methylenetetrahydrofolate reductase (MTHFR). Given that damage to the PFC leads to loss of executive function and addiction, our study may shed light on the mechanism of alcohol addiction. PMID:25188266

  2. Prior Binge Ethanol Exposure Potentiates the Microglial Response in a Model of Alcohol-Induced Neurodegeneration.

    PubMed

    Marshall, Simon Alex; Geil, Chelsea Rhea; Nixon, Kimberly

    2016-01-01

    Excessive alcohol consumption results in neurodegeneration which some hypothesize is caused by neuroinflammation. One characteristic of neuroinflammation is microglial activation, but it is now well accepted that microglial activation may be pro- or anti-inflammatory. Recent work indicates that the Majchrowicz model of alcohol-induced neurodegeneration results in anti-inflammatory microglia, while intermittent exposure models with lower doses and blood alcohol levels produce microglia with a pro-inflammatory phenotype. To determine the effect of a repeated binge alcohol exposure, rats received two cycles of the four-day Majchrowicz model. One hemisphere was then used to assess microglia via immunohistochemistry and while the other was used for ELISAs of cytokines and growth factors. A single binge ethanol exposure resulted in low-level of microglial activation; however, a second binge potentiated the microglial response. Specifically, double binge rats had greater OX-42 immunoreactivity, increased ionized calcium-binding adapter molecule 1 (Iba-1+) cells, and upregulated tumor necrosis factor-α (TNF-α) compared with the single binge ethanol group. These data indicate that prior ethanol exposure potentiates a subsequent microglia response, which suggests that the initial exposure to alcohol primes microglia. In summary, repeated ethanol exposure, independent of other immune modulatory events, potentiates microglial activity. PMID:27240410

  3. Alcohol-induced alterations in serum immunoglobulin e (IgE) levels in human subjects.

    PubMed

    González-Quintela, Arturo; Vidal, Carmen; Gude, Francisco

    2002-05-01

    The association of alcohol intake with total serum IgE concentrations in humans is discussed in the present review. The possible relationship of regular alcohol intake with both the risk of allergic sensitization and serum allergen-specific IgE values is also reviewed. Several studies consistently show that total serum IgE concentrations are increased in alcoholics when compared with healthy controls. Total serum IgE levels decrease after ethanol abstinence in alcoholics. Total serum IgE is increased in moderate alcohol consumers with respect to abstainers. Alcohol consumption in mothers may be associated with increased cord blood IgE levels in their offspring. IgE elevation in alcohol consumers is independent of potential confounders such as age, sex, liver disease, cigarette smoking or atopic status. Experimental studies in animals further support that ethanol administration is followed by an increase in serum IgE concentrations. In atopic patients, regular alcohol consumption is associated with increased serum specific IgE levels against some aeroallergens. Preliminary reports suggest that alcohol intake is associated to variable risk of sensitization to some aeroallergens. The possible mechanisms of alcohol-induced alterations in IgE levels and IgE-mediated diseases are discussed. PMID:11991851

  4. Osthole improves alcohol-induced fatty liver in mice by reduction of hepatic oxidative stress.

    PubMed

    Zhang, Jianjun; Xue, Jie; Wang, Hengbin; Zhang, Yan; Xie, Meilin

    2011-05-01

    The aim of our study was to examine the therapeutic effect of osthole, an active constituent isolated from the fruit of Cnidium monnieri (L.) Cusson, on alcohol-induced fatty liver in mice and investigate its potential mechanisms of treatment. A mouse alcoholic fatty liver model was established by feeding 52% alcohol for 4 weeks. These experimental mice were then treated with osthole 10, 20 and 40 mg/kg for 6 weeks. The levels of serum total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol (LDL-C) and hepatic tissue contents of TC, TG and malondialdehyde (MDA) in osthole-treated groups were significantly decreased, while the level of superoxide dismutase (SOD) was significantly increased compared with the model group. Moreover, the cytochrome P450 (CYP) 2E1 and diacylglycerol acyltransferase (DGAT) mRNA expressions in mouse liver were significantly decreased, and the carnitine palmitoyltransferase (CPT) 1A mRNA expression was increased by osthole treatment. Importantly, the histological evaluation of liver demonstrated that osthole dramatically decreased lipid accumulation. It was concluded that osthole was effective in treating mouse alcoholic fatty liver, and its main mechanisms might be related to reduction of hepatic oxidative stress, including the inhibition of reactive oxygen species (ROS) production, enhancement of antioxidative enzyme activity, and reduction of lipid accumulation and peroxidation. PMID:20981870

  5. Effect of resveratrol on alcohol-induced mortality and liver lesions in mice

    PubMed Central

    Bujanda, Luis; García-Barcina, María; Juan, Virginia Gutiérrez-de; Bidaurrazaga, Joseba; de Luco, Marian Fernández; Gutiérrez-Stampa, Marian; Larzabal, Mikel; Hijona, Elisabeth; Sarasqueta, Cristina; Echenique-Elizondo, Miguel; Arenas, Juan I

    2006-01-01

    Background Resveratrol is a polyphenol with important antiinflammatory and antioxidant properties. We investigated the effect of resveratrol on alcohol-induced mortality and liver lesions in mice. Methods Mice were randomly distributed into four groups (control, resveratrol-treated control, alcohol and resveratrol-treated alcohol). Chronic alcohol intoxication was induced by progressively administering alcohol in drinking water up to 40% v/v. The mice administered resveratrol received 10 mg/ml in drinking water. The animals had free access to standard diet. Blood levels were determined for transaminases, IL-1 and TNF-α. A histological evaluation was made of liver damage, and survival among the animals was recorded. Results Transaminase concentration was significantly higher in the alcohol group than in the rest of the groups (p < 0.05). IL-1 levels were significantly reduced in the alcohol plus resveratrol group compared with the alcohol group (p < 0.05). TNF-α was not detected in any group. Histologically, the liver lesions were more severe in the alcohol group, though no significant differences between groups were observed. Mortality in the alcohol group was 78% in the seventh week, versus 22% in the alcohol plus resveratrol group (p < 0.001). All mice in the alcohol group died before the ninth week. Conclusion The results obtained suggest that resveratrol reduces mortality and liver damage in mice. PMID:17105669

  6. The protective effects of carnosine in alcohol-induced hepatic injury in rats.

    PubMed

    Baykara, B; Micili, S Cilaker; Tugyan, K; Tekmen, I; Bagriyanik, Ha; Sonmez, U; Sonmez, A; Oktay, G; Yener, N; Ozbal, S

    2014-02-01

    Consumption of alcohol leads to oxidative stress in liver by inducing lipid peroxidation. The aim of this study was to investigate the effects of carnosine (CAR) in alcohol-induced liver injury by biochemical and histomorphological evaluations. The rats were divided into four groups, namely, control group, alcohol (AL) group, CAR group and AL + CAR group. Three doses of ethanol (5 g/kg, 25% (v/v) in distilled water) were given by nasogastric catheter for twice-a-day. CAR (100 mg/kg) was given 1 h before the administration of ethanol using the same method. Levels of alanine aminotransferase, aspartate aminotransferase, myeloperoxidase and malondialdehyde were significantly increased in the AL group compared with control, CAR and AL + CAR groups. Glutathione level was significantly decreased in the AL group, while it was increased in the AL + CAR group. Immunoreactivity of caspase-3 and bax increased in the hepatocytes of AL group when compared with control and AL + CAR groups. Expression of bcl-2 was decreased in AL group than AL + CAR group. Under electron microscopy, dense mitochondria, accumulation of lipid, sinusoidal dilatation, vacuolization and decrease in the number of microvilli were observed in AL group, while these findings were markedly less in the AL + CAR group. In conclusion, pretreatment of CAR is effective for recovering biochemical alterations and morphologic damage in the liver of rats treated with ethanol. PMID:22661399

  7. Synthesis, micellization behavior and alcohol induced amphipathic cellulose film of cellulose-based amphiphilic surfactant

    NASA Astrophysics Data System (ADS)

    Yang, Fang; Liu, Ya-nan; Yu, Jian-ling; Li, Hai-peng; Li, Gang

    2015-08-01

    This paper presented a novel preparation method of the cellulose-based amphiphilic surfactant, and the surfactant was used to prepare amphipathic cellulose membrane. The native cotton cellulose was tailored to cellulose segments in ionic liquid 1-butyl-3-methylimidazolium chloride. Then, the hydrophobic and hydrophilic modification of cellulose segments were carried out by esterification and graft polymerization of the ɛ-caprolactone (ɛ-CL) monomer onto the hydroxyl group of cellulose as well as sulphonation with sulfamic acid. The amphipathic cellulose membrane was made by cellulose-based amphiphilic surfactant cross-linking with glutaraldehyde. The molecular structure of amphipathic cellulose surfactant was confirmed by FT-IR, and its surface active properties were investigated by Wilhelmy plate method and Steady-state fluorescence probe method, respectively. Experimental results showed that cellulose-based amphiphilic surfactant caused low interfacial tension of 48.62 mN/m and its critical micelle concentration (cmc) value was 0.65 wt% when the grafting ratio of cellulose-g-PCL (poly-caprolactone) was 25.40%. The contact angle between a droplet of water and the surface of membrane was 90.84o, and the surface free energy of the alcohol induced cellulose membrane was 15.7 mJ/m2. This study may help increase using natural and biodegradable surface-activity materials with improved properties as surfactants.

  8. Analysis of Cell Death Induction in Intestinal Organoids In Vitro.

    PubMed

    Grabinger, Thomas; Delgado, Eugenia; Brunner, Thomas

    2016-01-01

    The intestinal epithelium has an important function in the absorption of nutrients contained in the food. Furthermore, it also has an important barrier function, preventing luminal pathogens from entering the bloodstream. This single cell layer epithelium is quite sensitive to various cell death-promoting triggers, including drugs, irradiation, and TNF family members, leading to loss of barrier integrity, epithelial erosion, inflammation, malabsorption, and diarrhea. In order to assess the intestinal epithelium-damaging potential of treatments and substances specific test systems are required. As intestinal tumor cell lines are a poor substitute for primary intestinal epithelial cells, and in vivo experiments in mice are costly and often unethical, the use of intestinal organoids cultured from intestinal crypts provide an ideal tool to study cell death induction and mechanisms in primary intestinal epithelial cells. This protocol describes the isolation and culture of intestinal organoids from murine small intestinal crypts, and the quantitative assessment of cell death induction in these organoids. PMID:27108433

  9. miR-339-5p inhibits alcohol-induced brain inflammation through regulating NF-κB pathway

    SciTech Connect

    Zhang, Yu; Wei, Guangkuan; Di, Zhiyong; Zhao, Qingjie

    2014-09-26

    Graphical abstract: - Highlights: • Alcohol upregulates miR-339-5p expression. • miR-339-5p inhibits the NF-kB pathway. • miR-339-5p interacts with and blocks activity of IKK-beat and IKK-epsilon. • miR-339-5p modulates IL-1β, IL-6 and TNF-α. - Abstract: Alcohol-induced neuroinflammation is mediated by the innate immunesystem. Pro-inflammatory responses to alcohol are modulated by miRNAs. The miRNA miR-339-5p has previously been found to be upregulated in alcohol-induced neuroinflammation. However, little has been elucidated on the regulatory functions of this miRNA in alcohol-induced neuroinflammation. We investigated the function of miR-339-5p in alcohol exposed brain tissue and isolated microglial cells using ex vivo and in vitro techniques. Our results show that alcohol induces transcription of miR 339-5p, IL-6, IL-1β and TNF-α in mouse brain tissue and isolated microglial cells by activating NF-κB. Alcohol activation of NF-κB allows for nuclear translocation of the NF-κB subunit p65 and expression of pro-inflammatory mediators. miR-339-5p inhibited expression of these pro-inflammatory factors through the NF-κB pathway by abolishing IKK-β and IKK-ε activity.

  10. Tamoxifen represses alcohol-induced transcription of RNA polymerase III-dependent genes in breast cancer cells

    PubMed Central

    Zhong, Qian; Shi, Ganggang; Zhang, Qingsong; Lu, Lei; Levy, Daniel; Zhong, Shuping

    2014-01-01

    Alcohol consumption in women has been associated with an increased risk of breast cancer, particular in estrogen receptor positive (ER+) cases. Deregulation of RNA polymerase III-dependent (Pol III) transcription enhances cellular tRNAs and 5S rRNA production, leading to an increase in translational capacity to promote cell transformation and tumor formation. Our recent studies demonstrated that alcohol induces Brf1 expression and Pol III gene transcription via ER. Here, we report that Tamoxifen (Tam) inhibits the induction of Brf1 and Pol III genes in ER+ breast cancer cells. Further analysis indicates that alcohol increases c-Jun expression to upregulate the transcription of Brf1 and Pol III genes, whereas Tam reduces c-Jun expression to repress the transcription of Brf1. Repression of cJun decreases cellular levels of ERα and Brf1. Alcohol-dependent increased occupancy of Brf1 in Pol III gene promoters is reduced by Tam. The repression of Brf1 and Pol III genes by Tam reduces alcohol-induced cell proliferation and colony formation. Together, these results indicate that Tam inhibits alcohol-induced Brf1 expression through c-Jun and ERα to downregulate Pol III gene transcription. Our studies uncover a new mechanism of Tam-treated ER+ breast cancer, by which Tam inhibits tumor growth through repressing Pol III gene transcription. PMID:25400119

  11. Intestinal Parasitoses.

    ERIC Educational Resources Information Center

    Lagardere, Bernard; Dumburgier, Elisabeth

    1994-01-01

    Intestinal parasites have become a serious public health problem in tropical countries because of the climate and the difficulty of achieving efficient hygiene. The objectives of this journal issue are to increase awareness of the individual and collective repercussions of intestinal parasites, describe the current conditions of contamination and…

  12. Intestinal Cancer

    MedlinePlus

    ... increase your risk. Possible signs of small intestine cancer include Abdominal pain Weight loss for no reason Blood in the stool A lump in the abdomen Imaging tests that create pictures of the small ... help diagnose intestinal cancer and show whether it has spread. Surgery is ...

  13. Rapid disruption of intestinal epithelial tight junction and barrier dysfunction by ionizing radiation in mouse colon in vivo: protection by N-acetyl-l-cysteine.

    PubMed

    Shukla, Pradeep K; Gangwar, Ruchika; Manda, Bhargavi; Meena, Avtar S; Yadav, Nikki; Szabo, Erzsebet; Balogh, Andrea; Lee, Sue Chin; Tigyi, Gabor; Rao, RadhaKrishna

    2016-05-01

    The goals of this study were to evaluate the effects of ionizing radiation on apical junctions in colonic epithelium and mucosal barrier function in mice in vivo. Adult mice were subjected to total body irradiation (4 Gy) with or without N-acetyl-l-cysteine (NAC) feeding for 5 days before irradiation. At 2-24 h postirradiation, the integrity of colonic epithelial tight junctions (TJ), adherens junctions (AJ), and the actin cytoskeleton was assessed by immunofluorescence microscopy and immunoblot analysis of detergent-insoluble fractions for TJ and AJ proteins. The barrier function was evaluated by measuring vascular-to-luminal flux of fluorescein isothiocyanate (FITC)-inulin in vivo and luminal-to-mucosal flux in vitro. Oxidative stress was evaluated by measuring protein thiol oxidation. Confocal microscopy showed that radiation caused redistribution of occludin, zona occludens-1, claudin-3, E-cadherin, and β-catenin, as well as the actin cytoskeleton as early as 2 h postirradiation, and this effect was sustained for at least 24 h. Feeding NAC before irradiation blocked radiation-induced disruption of TJ, AJ, and the actin cytoskeleton. Radiation increased mucosal permeability to inulin in colon, which was blocked by NAC feeding. The level of reduced-protein thiols in colon was depleted by radiation with a concomitant increase in the level of oxidized-protein thiol. NAC feeding blocked the radiation-induced protein thiol oxidation. These data demonstrate that radiation rapidly disrupts TJ, AJ, and the actin cytoskeleton by an oxidative stress-dependent mechanism that can be prevented by NAC feeding. PMID:26822914

  14. Alcohol Induced Depressive-Like Behavior is Associated with a Reduction in Hippocampal BDNF

    PubMed Central

    Hauser, Sheketha R.; Getachew, Bruk; Taylor, Robert E.; Tizabi, Yousef

    2011-01-01

    Strong positive correlation between depression and alcoholism is evident in epidemiological reports. However, a causal relationship for this co-morbidity has not been established. We have observed that chronic daily exposure to a relatively high dose of alcohol can induce depressive-like behavior in rats and that pretreatment with nomifensine or imipramine can block the “depressogenic” effects of alcohol. Since brain derived neurotrophic factor (BDNF) is considered to play an important role in depressive-like behaviors and its elevation, particularly in the hippocampus, appears to be critical for the action of many antidepressants, we hypothesized that: 1. WKY rats, a putative animal model of depression, will show a lower hippocampal BDNF compared to their control Wistar rats, 2. Alcohol-induced depressive like behavior will be associated with a significant decrease in hippocampal BDNF and 3. Treatments with antidepressants will normalize hippocampal BDNF. These postulates were verified by measuring hippocampal BDNF in Wistar and WKY rats at baseline, following chronic (10 day) treatment with alcohol and combination of alcohol with nomifensine or imipramine. Alcohol was administered via inhalation chamber (3 hr/day) such that a blood alcohol level of approximately 150 mg% was achieved. Nomifensine (10 mg/kg) or impiramine (10 mg/kg) were administered i.p daily immediately after alcohol exposure. BDNF was measured by standard Elisa kit. The results support a role for central BDNF in depressogenic effects of alcohol and antidepressant effects of nomifensine and imipramine. Moreover, depression per se as manifested in WKY rats may be associated with a reduction in hippocampal BDNF. PMID:21930150

  15. Alcohol-induced autophagy contributes to loss in skeletal muscle mass

    PubMed Central

    Thapaliya, Samjhana; Runkana, Ashok; McMullen, Megan R; Nagy, Laura E; McDonald, Christine; Prasad, Sathyamangla V Naga; Dasarathy, Srinivasan

    2014-01-01

    Patients with alcoholic cirrhosis and hepatitis have severe muscle loss. Since ethanol impairs skeletal muscle protein synthesis but does not increase ubiquitin proteasome-mediated proteolysis, we investigated whether alcohol-induced autophagy contributes to muscle loss. Autophagy induction was studied in: A) Human skeletal muscle biopsies from alcoholic cirrhotics and controls, B) Gastrocnemius muscle from ethanol and pair-fed mice, and C) Ethanol-exposed murine C2C12 myotubes, by examining the expression of autophagy markers assessed by immunoblotting and real-time PCR. Expression of autophagy genes and markers were increased in skeletal muscle from humans and ethanol-fed mice, and in myotubes following ethanol exposure. Importantly, pulse-chase experiments showed suppression of myotube proteolysis upon ethanol-treatment with the autophagy inhibitor, 3-methyladenine (3MA) and not by MG132, a proteasome inhibitor. Correspondingly, ethanol-treated C2C12 myotubes stably expressing GFP-LC3B showed increased autophagy flux as measured by accumulation of GFP-LC3B vesicles with confocal microscopy. The ethanol-induced increase in LC3B lipidation was reversed upon knockdown of Atg7, a critical autophagy gene and was associated with reversal of the ethanol-induced decrease in myotube diameter. Consistently, CT image analysis of muscle area in alcoholic cirrhotics was significantly reduced compared with control subjects. In order to determine whether ethanol per se or its metabolic product, acetaldehyde, stimulates autophagy, C2C12 myotubes were treated with ethanol in the presence of the alcohol dehydrogenase inhibitor (4-methylpyrazole) or the acetaldehyde dehydrogenase inhibitor (cyanamide). LC3B lipidation increased with acetaldehyde treatment and increased further with the addition of cyanamide. We conclude that muscle autophagy is increased by ethanol exposure and contributes to sarcopenia. PMID:24492484

  16. Alcohol-induced defects in hepatic transcytosis may be explained by impaired dynein function

    PubMed Central

    Groebner, Jennifer L.; Fernandez, David J.; Tuma, Dean J.; Tuma, Pamela L.

    2016-01-01

    Alcoholic liver disease has been clinically well described, but the molecular mechanisms leading to hepatotoxicity have not been fully elucidated. Previously, we determined that microtubules are hyperacetylated and more stable in ethanol-treated WIF-B cells, VL-17A cells, liver slices, and in livers from ethanol-fed rats. From our recent studies, we believe that these modifications can explain alcohol-induced defects in microtubule motor-dependent protein trafficking including nuclear translocation of a subset of transcription factors. Since cytoplasmic dynein/dynactin is known to mediate both microtubule-dependent translocation and basolateral to apical/canalicular transcytosis, we predicted that transcytosis is impaired in ethanol-treated hepatic cells. We monitored transcytosis of three classes of newly synthesized canalicular proteins in polarized, hepatic WIF-B cells, an emerging model system for the study of liver disease. As predicted, canalicular delivery of all proteins tested was impaired in ethanol-treated cells. Unlike in control cells, transcytosing proteins were observed in discrete sub-canalicular puncta en route to the canalicular surface that aligned along acetylated microtubules. We further determined that the stalled transcytosing proteins colocalized with dynein/dynactin in treated cells. No changes in vesicle association were observed for either dynein or dynactin in ethanol-treated cells, but significantly enhanced dynein binding to micro-tubules was observed. From these results, we propose that enhanced dynein binding to microtubules in ethanol-treated cells leads to decreased motor processivity resulting in vesicle stalling and in impaired canalicular delivery. Our studies also importantly indicate that modulating cellular acetylation levels with clinically tolerated deacetylase agonists may be a novel therapeutic strategy for treating alcoholic liver disease. PMID:25148871

  17. Alcohol-induced defects in hepatic transcytosis may be explained by impaired dynein function.

    PubMed

    Groebner, Jennifer L; Fernandez, David J; Tuma, Dean J; Tuma, Pamela L

    2014-12-01

    Alcoholic liver disease has been clinically well described, but the molecular mechanisms leading to hepatotoxicity have not been fully elucidated. Previously, we determined that microtubules are hyperacetylated and more stable in ethanol-treated WIF-B cells, VL-17A cells, liver slices, and in livers from ethanol-fed rats. From our recent studies, we believe that these modifications can explain alcohol-induced defects in microtubule motor-dependent protein trafficking including nuclear translocation of a subset of transcription factors. Since cytoplasmic dynein/dynactin is known to mediate both microtubule-dependent translocation and basolateral to apical/canalicular transcytosis, we predicted that transcytosis is impaired in ethanol-treated hepatic cells. We monitored transcytosis of three classes of newly synthesized canalicular proteins in polarized, hepatic WIF-B cells, an emerging model system for the study of liver disease. As predicted, canalicular delivery of all proteins tested was impaired in ethanol-treated cells. Unlike in control cells, transcytosing proteins were observed in discrete sub-canalicular puncta en route to the canalicular surface that aligned along acetylated microtubules. We further determined that the stalled transcytosing proteins colocalized with dynein/dynactin in treated cells. No changes in vesicle association were observed for either dynein or dynactin in ethanol-treated cells, but significantly enhanced dynein binding to microtubules was observed. From these results, we propose that enhanced dynein binding to microtubules in ethanol-treated cells leads to decreased motor processivity resulting in vesicle stalling and in impaired canalicular delivery. Our studies also importantly indicate that modulating cellular acetylation levels with clinically tolerated deacetylase agonists may be a novel therapeutic strategy for treating alcoholic liver disease. PMID:25148871

  18. Protective effects of hydroxysafflor yellow A (HSYA) on alcohol-induced liver injury in rats.

    PubMed

    He, Yanhao; Liu, Qiang; Li, Yanxiang; Yang, Xiaofeng; Wang, Weirong; Li, Tingting; Zhang, Wei; Cui, Yuexin; Wang, Chaoyun; Lin, Rong

    2015-03-01

    Hydroxysafflor yellow A (HSYA), the main active natural constituent extracted from Carthamus tinctorius L., has been widely used for the treatment of cerebrovascular and cardiovascular diseases. The aim of this study is to explore the effect of HSYA on alcohol-induced liver injury and the underlying mechanism. Male Sprague-Dawley rats were used to establish the liver injury model induced by alcohol. HSYA treatment ameliorated serum biochemical indicators by reducing the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronan (HA), laminin (LN), and type III precollagen (III-C) in rats. HSYA efficiently increased the activity and messenger RNA (mRNA) of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in rat liver tissue compared with those of model group, which was obviously reduced by alcohol. HSYA also apparently decreased the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) in rat liver tissue compared with those of model group, which was obviously enhanced by alcohol. Histological studies demonstrated that HSYA substantially reduced the number of macro- and micro-vesicular steatosis, suppressed hepatic fibrogenesis and shrunk ballooning degeneration areas, ameliorated the severity of liver damage induced by long-term drinking, and finally improved the liver architecture. In addition, immunohistochemistry study indicated that the activation of transforming growth factor β1 (TGF-β1) stimulated by alcohol in rat liver tissue was significantly blocked by HSYA. Collectively, these data demonstrated that HSYA can effectively protect the liver of rats from long-term alcohol injury, which relates with the enhanced antioxidant capacity of liver tissues and inhibition of TGF-β1 expression. PMID:25626885

  19. Intestinal steroidogenesis.

    PubMed

    Bouguen, Guillaume; Dubuquoy, Laurent; Desreumaux, Pierre; Brunner, Thomas; Bertin, Benjamin

    2015-11-01

    Steroids are fundamental hormones that control a wide variety of physiological processes such as metabolism, immune functions, and sexual characteristics. Historically, steroid synthesis was considered a function restricted to the adrenals and the gonads. In the past 20 years, a significant number of studies have demonstrated that steroids could also be synthesized or metabolized by other organs. According to these studies, the intestine appears to be a major source of de novo produced glucocorticoids as well as a tissue capable of producing and metabolizing sex steroids. This finding is based on the detection of steroidogenic enzyme expression as well as the presence of bioactive steroids in both the rodent and human gut. Within the intestinal mucosa, the intestinal epithelial cell layer is one of the main cellular sources of steroids. Glucocorticoid synthesis regulation in the intestinal epithelial cells is unique in that it does not involve the classical positive regulator steroidogenic factor-1 (SF-1) but a closely related homolog, namely the liver receptor homolog-1 (LRH-1). This local production of immunoregulatory glucocorticoids contributes to intestinal homeostasis and has been linked to pathophysiology of inflammatory bowel diseases. Intestinal epithelial cells also possess the ability to metabolize sex steroids, notably estrogen; this mechanism may impact colorectal cancer development. In this review, we contextualize and discuss what is known about intestinal steroidogenesis and regulation as well as the key role these functions play both in physiological and pathological conditions. PMID:25560486

  20. [Epithelial cell in intestinal homeostasis and inflammatory bowel diseases].

    PubMed

    Zouiten-Mekki, Lilia; Serghini, Meriem; Fekih, Monia; Kallel, Lamia; Matri, Samira; Ben Mustapha, Nadia; Boubaker, Jalel; Filali, Azza

    2013-12-01

    Crohn's disease (CD) and ulcerative colitis (UC) are the principal inflammatory bowel diseases (IBD) which physiopathology is currently poorly elucidated. During these diseases, the participation of the epithelial cell in the installation and the perpetuation of the intestinal inflammation is now clearly implicated. In fact, the intestinal epithelium located at the interface between the internal environment and the intestinal luminal, is key to the homeostatic regulation of the intestinal barrier. This barrier can schematically be regarded as being three barriers in one: a physical, chemical and immune barrier. The barrier function of epithelial cell can be altered by various mechanisms as occurs in IBD. The goal of this article is to review the literature on the role of the epithelial cell in intestinal homeostasis and its implication in the IBD. PMID:24356146

  1. Quantitative In Vitro and In Vivo Evaluation of Intestinal and Blood-Brain Barrier Transport Kinetics of the Plant N-Alkylamide Pellitorine.

    PubMed

    Veryser, Lieselotte; Bracke, Nathalie; Wynendaele, Evelien; Joshi, Tanmayee; Tatke, Pratima; Taevernier, Lien; De Spiegeleer, Bart

    2016-01-01

    Objective. To evaluate the gut mucosa and blood-brain barrier (BBB) pharmacokinetic permeability properties of the plant N-alkylamide pellitorine. Methods. Pure pellitorine and an Anacyclus pyrethrum extract were used to investigate the permeation of pellitorine through (1) a Caco-2 cell monolayer, (2) the rat gut after oral administration, and (3) the BBB in mice after intravenous and intracerebroventricular administration. A validated bioanalytical UPLC-MS(2) method was used to quantify pellitorine. Results. Pellitorine was able to cross the Caco-2 cell monolayer from the apical-to-basolateral and from the basolateral-to-apical side with apparent permeability coefficients between 0.6 · 10(-5) and 4.8 · 10(-5) cm/h and between 0.3 · 10(-5) and 5.8 · 10(-5) cm/h, respectively. In rats, a serum elimination rate constant of 0.3 h(-1) was obtained. Intravenous injection of pellitorine in mice resulted in a rapid and high permeation of pellitorine through the BBB with a unidirectional influx rate constant of 153 μL/(g·min). In particular, 97% of pellitorine reached the brain tissue, while only 3% remained in the brain capillaries. An efflux transfer constant of 0.05 min(-1) was obtained. Conclusion. Pellitorine shows a good gut permeation and rapidly permeates the BBB once in the blood, indicating a possible role in the treatment of central nervous system diseases. PMID:27493960

  2. Quantitative In Vitro and In Vivo Evaluation of Intestinal and Blood-Brain Barrier Transport Kinetics of the Plant N-Alkylamide Pellitorine

    PubMed Central

    Veryser, Lieselotte; Bracke, Nathalie; Wynendaele, Evelien; Joshi, Tanmayee; Tatke, Pratima; Taevernier, Lien

    2016-01-01

    Objective. To evaluate the gut mucosa and blood-brain barrier (BBB) pharmacokinetic permeability properties of the plant N-alkylamide pellitorine. Methods. Pure pellitorine and an Anacyclus pyrethrum extract were used to investigate the permeation of pellitorine through (1) a Caco-2 cell monolayer, (2) the rat gut after oral administration, and (3) the BBB in mice after intravenous and intracerebroventricular administration. A validated bioanalytical UPLC-MS2 method was used to quantify pellitorine. Results. Pellitorine was able to cross the Caco-2 cell monolayer from the apical-to-basolateral and from the basolateral-to-apical side with apparent permeability coefficients between 0.6 · 10−5 and 4.8 · 10−5 cm/h and between 0.3 · 10−5 and 5.8 · 10−5 cm/h, respectively. In rats, a serum elimination rate constant of 0.3 h−1 was obtained. Intravenous injection of pellitorine in mice resulted in a rapid and high permeation of pellitorine through the BBB with a unidirectional influx rate constant of 153 μL/(g·min). In particular, 97% of pellitorine reached the brain tissue, while only 3% remained in the brain capillaries. An efflux transfer constant of 0.05 min−1 was obtained. Conclusion. Pellitorine shows a good gut permeation and rapidly permeates the BBB once in the blood, indicating a possible role in the treatment of central nervous system diseases. PMID:27493960

  3. Intestinal obstruction

    MedlinePlus

    Obstruction of the bowel may due to: A mechanical cause, which means something is in the way ... lung disease Use of certain medicines, especially narcotics Mechanical causes of intestinal obstruction may include: Adhesions or ...

  4. Alcohol Induced Facial Dysmorphology in C57BL/6 Mouse Models of Fetal Alcohol Spectrum Disorder

    PubMed Central

    Anthony, Bruce; Vinci-Booher, Sophia; Wetherill, Leah; Ward, Richard; Goodlett, Charles; Zhou, Feng C.

    2010-01-01

    pair feeding on these facial measures than did B6J, suggesting that the B6N sub-strain may be more vulnerable to nutritional stress during pregnancy. Overall, these data indicate that B6N and B6J mice were both vulnerable to alcohol but show differences in the severity and location of alcohol-induced dysmorphic facial features and may parallel findings from human studies comparing different ethnic groups. Furthermore these findings suggest that discriminant analysis may be useful in predicting alcohol exposure in either mouse sub-strain. PMID:20570474

  5. Schisandra chinensis Prevents Alcohol-Induced Fatty Liver Disease in Rats

    PubMed Central

    Park, Hyoung Joon; Lee, Soo-Jung; Song, Yuno; Jang, Sun-Hee; Ko, Yeoung-Gyu; Kang, Suk Nam; Chung, Byung Yeoup; Kim, Hong-Duck; Kim, Gon-Sup

    2014-01-01

    Abstract Schisandra chinensis (SC), a traditional herbal medicine, has been prescribed for patients suffering from various liver diseases, including hepatic cancer, hypercholesterolemia, and CCl4-induced liver injury. We investigated whether SC extract has a protective effect on alcohol-induced fatty liver and studied its underlying mechanisms. Rats were fed with ethanol by intragastric administration every day for 5 weeks to induce alcoholic fatty liver. Ethanol treatment resulted in a significant increase in alanine aminotransferase, aspartate aminotransferase, and hepatic triglyceride (TG) levels and caused fatty degeneration of liver. Ethanol administration also elevated serum TG and total cholesterol (TC) and decreased high-density lipoprotein (HDL) cholesterol levels. However, after administration of ethanol plus SC extracts, the ethanol-induced elevation in liver TC and TG levels was reversed. Elevation in serum TG was not observed after treatment with SC. Moreover, compared with the ethanol-fed group, the rats administered ethanol along with SC extracts for 5 weeks showed attenuated fatty degeneration and an altered lipid profile with decreased serum TC and TG, and increased HDL cholesterol levels. Chronic ethanol consumption did not affect peroxisome proliferator-activated receptor γ (PPARγ) levels, but it decreased PPARα and phospho-AMP-activated protein kinase (AMPK) levels in the liver. However, SC prevented the ethanol-induced decrease in PPARα expression and induced a significant decrease in sterol regulatory element-binding protein-1 expression and increase in phospho-AMPK expression in rats with alcoholic fatty liver. SC administration resulted in a significant decrease in intracellular lipid accumulation in hepatocytes along with a decrease in serum TG levels, and it reversed fatty liver to normal conditions, as measured by biochemical and histological analyses. Our results indicate that the protective effect of SC is accompanied by a

  6. Genetic association of the ApoB and ApoA1 gene polymorphisms with the risk for alcohol-induced osteonecrosis of femoral head

    PubMed Central

    Wang, Yuan; Cao, Yuju; Li, Yizhou; Guo, Yongchang; Wang, Quanjian; Yang, Min; Zhang, Ning; Jin, Tianbo; Wang, Jianzhong

    2015-01-01

    Polymorphisms of apolipoprotein B (ApoB), apolipoprotein A1 (ApoA1) gene and ApoB/ApoA1 Ratio were associated with lipid metabolism disorders in previous reports. The aim of this study assess whether variation of ApoB, ApoA1 gene are associated or not with alcohol-induced osteonecrosis of femoral head (ONFH). In a case-control study, we genotyped 4 single-nucleotide polymorphisms (SNPs) in ApoB and ApoA1 genes in 209 alcohol-induced ONFH patients and 300 healthy control subjects in Han Chinese population using χ2 test and genetic model analysis. The analysis revealed that the frequencies of ApoB and ApoA1 genotypes were significantly different in alcohol-induced ONFH patients than in controls. We identified rs1042034, rs676210 and rs673548 in ApoB gene were associated with decreased risk of alcohol-induced ONFH using recessive model analysis (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.19-0.99; P = 0.042), the OR, CI, P value of three SNPs were the same after adjusted for gender + age. We also identified rs632153 in ApoA1 gene was associated with increased risk of alcohol-induced ONFH using allele model (OR, 1.83; 95% CI, 1.16-2.88; P = 0.008) and log-additive model (adjusted OR, 1.77; 95% CI, 1.00-3.14; P = 0.046), analysis respectively. Haplotype analysis demonstrated no difference between ApoB and alcohol-induced ONFH. Polymorphisms of the ApoB and ApoA1 gene are associated with alcohol-induced ONFH in the Han Chinese population. PMID:26617857

  7. Parkin regulates mitophagy and mitochondrial function to protect against alcohol-induced liver injury and steatosis in mice.

    PubMed

    Williams, Jessica A; Ni, Hong-Min; Ding, Yifeng; Ding, Wen-Xing

    2015-09-01

    Alcoholic liver disease claims two million lives per year. We previously reported that autophagy protected against alcohol-induced liver injury and steatosis by removing damaged mitochondria. However, the mechanisms for removal of these mitochondria are unknown. Parkin is an evolutionarily conserved E3 ligase that is recruited to damaged mitochondria to initiate ubiquitination of mitochondrial outer membrane proteins and subsequent mitochondrial degradation by mitophagy. In addition to its role in mitophagy, Parkin has been shown to have other roles in maintaining mitochondrial function. We investigated whether Parkin protected against alcohol-induced liver injury and steatosis using wild-type (WT) and Parkin knockout (KO) mice treated with alcohol by the acute-binge and Gao-binge (chronic plus acute-binge) models. We found that Parkin protected against liver injury in both alcohol models, likely because of Parkin's role in maintaining a population of healthy mitochondria. Alcohol caused greater mitochondrial damage and oxidative stress in Parkin KO livers compared with WT livers. After alcohol treatment, Parkin KO mice had severely swollen and damaged mitochondria that lacked cristae, which were not seen in WT mice. Furthermore, Parkin KO mice had decreased mitophagy, β-oxidation, mitochondrial respiration, and cytochrome c oxidase activity after acute alcohol treatment compared with WT mice. Interestingly, liver mitochondria seemed able to adapt to alcohol treatment, but Parkin KO mouse liver mitochondria had less capacity to adapt to Gao-binge treatment compared with WT mouse liver mitochondria. Overall, our findings indicate that Parkin is an important mediator of protection against alcohol-induced mitochondrial damage, steatosis, and liver injury. PMID:26159696

  8. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex

    PubMed Central

    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S.; Smolka, Michael N.

    2014-01-01

    Background A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. Methods We measured inhibitory control in fifty young adults with a stop-signal task (SST) during functional magnetic resonance imaging (fMRI). In a single-blind placebo-controlled cross-over design, all participants performed the SST once under alcohol with a breath alcohol concentration (BrAC) of 0.6 g/kg, and once under placebo. In addition, alcohol consumption was assessed using a free-access alcohol self-administration (ASA) paradigm in the same participants. Results Inhibitory control was robustly decreased under alcohol compared to placebo indicated by longer stop-signal reaction times (SSRTs). On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals, and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. Conclusion We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control may enhance alcohol consumption in young adults which might promote future alcohol problems. PMID:24560581

  9. Alteration of BRCA1 expression affects alcohol-induced transcription of RNA Pol III-dependent genes

    PubMed Central

    Zhong, Qian; Shi, Ganggang; Zhang, Yanmei; Lu, Lei; Levy, Daniel; Zhong, Shuping

    2014-01-01

    Emerging evidence has indicated that alcohol consumption is an established risk factor for breast cancer. Deregulation of RNA polymerase III (Pol III) transcription enhances cellular Pol III gene production, leading to an increase in translational capacity to promote cell transformation and tumor formation. We have reported that alcohol intake increases Pol III gene transcription to promote cell transformation and tumor formation in vitro and in vivo. Studies revealed that tumor suppressors, pRb, p53, PTEN and Maf1 repress the transcription of Pol III genes. BRCA1 is a tumor suppressor and its mutation is tightly related to breast cancer development. However, it is not clear whether BRCA1 expression affects alcohol-induced transcription of Pol III genes. At the present studies, we report that restoring BRCA1 in HCC 1937 cells, which is a BRCA1 deficient cell line, represses Pol III gene transcription. Expressing mutant or truncated BRCA1 in these cells does not affect the ability of repression on Pol III genes. Our analysis has demonstrated that alcohol induces Pol III gene transcription. More importantly, overexpression of BRCA1 in estrogen receptor positive (ER+) breast cancer cells (MCF-7) decreases the induction of tRNALeu and 5S rRNA genes by alcohol, whereas reduction of BRCA1 by its siRNA slightly increases the transcription of the class of genes. This suggests that BRCA1 is associated with alcohol-induced deregulation of Pol III genes. These studies for the first time demonstrate the role of BRCA1 in induction of Pol III genes by alcohol and uncover a novel mechanism of alcohol-associated breast cancer. PMID:25447904

  10. Parkin regulates mitophagy and mitochondrial function to protect against alcohol-induced liver injury and steatosis in mice

    PubMed Central

    Williams, Jessica A.; Ni, Hong-Min; Ding, Yifeng

    2015-01-01

    Alcoholic liver disease claims two million lives per year. We previously reported that autophagy protected against alcohol-induced liver injury and steatosis by removing damaged mitochondria. However, the mechanisms for removal of these mitochondria are unknown. Parkin is an evolutionarily conserved E3 ligase that is recruited to damaged mitochondria to initiate ubiquitination of mitochondrial outer membrane proteins and subsequent mitochondrial degradation by mitophagy. In addition to its role in mitophagy, Parkin has been shown to have other roles in maintaining mitochondrial function. We investigated whether Parkin protected against alcohol-induced liver injury and steatosis using wild-type (WT) and Parkin knockout (KO) mice treated with alcohol by the acute-binge and Gao-binge (chronic plus acute-binge) models. We found that Parkin protected against liver injury in both alcohol models, likely because of Parkin's role in maintaining a population of healthy mitochondria. Alcohol caused greater mitochondrial damage and oxidative stress in Parkin KO livers compared with WT livers. After alcohol treatment, Parkin KO mice had severely swollen and damaged mitochondria that lacked cristae, which were not seen in WT mice. Furthermore, Parkin KO mice had decreased mitophagy, β-oxidation, mitochondrial respiration, and cytochrome c oxidase activity after acute alcohol treatment compared with WT mice. Interestingly, liver mitochondria seemed able to adapt to alcohol treatment, but Parkin KO mouse liver mitochondria had less capacity to adapt to Gao-binge treatment compared with WT mouse liver mitochondria. Overall, our findings indicate that Parkin is an important mediator of protection against alcohol-induced mitochondrial damage, steatosis, and liver injury. PMID:26159696

  11. Platycodin D isolated from the aerial parts of Platycodon grandiflorum protects alcohol-induced liver injury in mice.

    PubMed

    Li, Wei; Liu, Ying; Wang, Zi; Han, Ye; Tian, Yu-Hong; Zhang, Gui-Shan; Sun, Yin-Shi; Wang, Ying-Ping

    2015-05-01

    Platycodin D (PD) is the main active saponin of Platycodon grandiflorum (PG) and is reported to exhibit multiple biological effects, including anti-tumor, anti-inflammation, and anti-obesity properties. Although recently there have been many research reports on the chemical constituents of the plant's roots, only few works have been reported on the aerial parts of PG. In the present study, we report the first isolation of PD from the aerial parts of PG and its protective effect against acute alcohol-induced liver oxidative injury and inflammatory response in mice. In brief, the protective effect was evaluated by tracking biochemical markers, enzymatic antioxidants and proinflammatory cytokines in serum and liver tissue. The results indicated that PD pretreatment significantly decreased the levels of triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (L-DLC) in serum and malondialdehyde (MDA) in liver. PD was also found to increase the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in the liver (p < 0.05). In addition, PD markedly decreased the levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6, which was caused by alcohol exposure (p < 0.05). In contrast, histopathological examinations revealed that PD pretreatment noticeably prevented alcohol-induced hepatocyte apoptosis and steatosis. Collectively, the present study clearly suggests that the protective effect exhibited by PD on alcohol-induced liver oxidative injury may occur via the alleviation of oxidative stress and inflammatory response. PMID:25927324

  12. Small Intestine Disorders

    MedlinePlus

    ... disease Crohn's disease Infections Intestinal cancer Intestinal obstruction Irritable bowel syndrome Ulcers, such as peptic ulcer Treatment of disorders of the small intestine depends on the cause.

  13. An intestinal Trojan horse for gene delivery

    NASA Astrophysics Data System (ADS)

    Peng, Haisheng; Wang, Chao; Xu, Xiaoyang; Yu, Chenxu; Wang, Qun

    2015-02-01

    The intestinal epithelium forms an essential element of the mucosal barrier and plays a critical role in the pathophysiological response to different enteric disorders and diseases. As a major enteric dysfunction of the intestinal tract, inflammatory bowel disease is a genetic disease which results from the inappropriate and exaggerated mucosal immune response to the normal constituents in the mucosal microbiota environment. An intestine targeted drug delivery system has unique advantages in the treatment of inflammatory bowel disease. As a new concept in drug delivery, the Trojan horse system with the synergy of nanotechnology and host cells can achieve better therapeutic efficacy in specific diseases. Here, we demonstrated the feasibility of encapsulating DNA-functionalized gold nanoparticles into primary isolated intestinal stem cells to form an intestinal Trojan horse for gene regulation therapy of inflammatory bowel disease. This proof-of-concept intestinal Trojan horse will have a wide variety of applications in the diagnosis and therapy of enteric disorders and diseases.

  14. An intestinal Trojan horse for gene delivery.

    PubMed

    Peng, Haisheng; Wang, Chao; Xu, Xiaoyang; Yu, Chenxu; Wang, Qun

    2015-03-14

    The intestinal epithelium forms an essential element of the mucosal barrier and plays a critical role in the pathophysiological response to different enteric disorders and diseases. As a major enteric dysfunction of the intestinal tract, inflammatory bowel disease is a genetic disease which results from the inappropriate and exaggerated mucosal immune response to the normal constituents in the mucosal microbiota environment. An intestine targeted drug delivery system has unique advantages in the treatment of inflammatory bowel disease. As a new concept in drug delivery, the Trojan horse system with the synergy of nanotechnology and host cells can achieve better therapeutic efficacy in specific diseases. Here, we demonstrated the feasibility of encapsulating DNA-functionalized gold nanoparticles into primary isolated intestinal stem cells to form an intestinal Trojan horse for gene regulation therapy of inflammatory bowel disease. This proof-of-concept intestinal Trojan horse will have a wide variety of applications in the diagnosis and therapy of enteric disorders and diseases. PMID:25619169

  15. Distinct shifts in microbiota composition during Drosophila aging impair intestinal function and drive mortality

    PubMed Central

    Clark, Rebecca I.; Salazar, Anna; Yamada, Ryuichi; Fitz-Gibbon, Sorel; Morselli, Marco; Alcaraz, Jeanette; Rana, Anil; Rera, Michael; Pellegrini, Matteo; Ja, William W.; Walker, David W.

    2015-01-01

    Summary Alterations in the composition of the intestinal microbiota have been correlated with aging and measures of frailty in the elderly. However, the relationships between microbial dynamics, age-related changes in intestinal physiology and organismal health remain poorly understood. Here, we show that dysbiosis of the intestinal microbiota, characterized by an expansion of the Gammaproteobacteria, is tightly linked to age-onset intestinal barrier dysfunction in Drosophila. Indeed, alterations in the microbiota precede and predict the onset of intestinal barrier dysfunction in aged flies. Changes in microbial composition occurring prior to intestinal barrier dysfunction contribute to changes in excretory function and immune gene activation in the aging intestine. In addition, we show that a distinct shift in microbiota composition follows intestinal barrier dysfunction leading to systemic immune activation and organismal death. Our results indicate that alterations in microbiota dynamics could contribute to and also predict varying rates of health decline during aging in mammals. PMID:26321641

  16. Fortilin potentiates the peroxidase activity of Peroxiredoxin-1 and protects against alcohol-induced liver damage in mice

    PubMed Central

    Chattopadhyay, Abhijnan; Pinkaew, Decha; Doan, Hung Q.; Jacob, Reed B.; Verma, Sunil K.; Friedman, Hana; Peterson, Alan C.; Kuyumcu-Martinez, Muge N.; McDougal, Owen M.; Fujise, Ken

    2016-01-01

    Fortilin, a pro-survival molecule, inhibits p53-induced apoptosis by binding to the sequence-specific DNA-binding domain of the tumor suppressor protein and preventing it from transcriptionally activating Bax. Intriguingly, fortilin protects cells against ROS-induced cell death, independent of p53. The signaling pathway through which fortilin protects cells against ROS-induced cell death, however, is unknown. Here we report that fortilin physically interacts with the antioxidant enzyme peroxiredoxin-1 (PRX1), protects it from proteasome-mediated degradation, and keeps it enzymatically active by blocking its deactivating phosphorylation by Mst1, a serine/threonine kinase. At the whole animal level, the liver-specific overexpression of fortilin reduced PRX1 phosphorylation in the liver, enhanced PRX1 activity, and protected the transgenic animals against alcohol-induced, ROS-mediated, liver damage. These data suggest the presence of a novel oxidative-stress-handling pathway where the anti-p53 molecule fortilin augments the peroxidase PRX1 by protecting it against degradation and inactivation of the enzyme. Fortilin-PRX1 interaction in the liver could be clinically exploited further to prevent acute alcohol-induced liver damage in humans. PMID:26726832

  17. Crepidiastrum denticulatum Extract Protects the Liver Against Chronic Alcohol-Induced Damage and Fat Accumulation in Rats

    PubMed Central

    Yoo, Ji-Hye; Kang, Kyungsu; Yun, Ji Ho; Kim, Mi Ae

    2014-01-01

    Abstract Alcohol is a severe hepatotoxicant that causes liver abnormalities such as steatosis, cirrhosis, and hepatocarcinoma. Crepidiastrum denticulatum (CD) is a well-known, traditionally consumed vegetable in Korea, which was recently reported to have bioactive compounds with detoxification and antioxidant properties. In this study, we report the hepatoprotective effect of CD extract against chronic alcohol-induced liver damage in vivo. The rats that were given CD extract exhibited decreased alanine aminotransferase, aspartate aminotransferase, and γ-glutamyl transpeptidase activities, which are liver damage markers that are typically elevated by alcohol consumption. The results were confirmed by histopathology with hematoxylin and eosin staining. Chronic alcohol consumption induced the formation of alcoholic fatty liver. However, treatment with CD extract dramatically decreased the hepatic lipid droplets. Treatment with CD extract also restored the antioxidative capacity and lipid peroxidation of the liver that had been changed by alcohol consumption. Furthermore, treatment with CD extract normalized the activities of the antioxidative enzymes superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase, which had been decreased by alcohol consumption. The results indicate that CD extract has protective effects against chronic alcohol hepatotoxicity in rats by increasing the liver's antioxidant capacity, and has potential as a dietary supplement intervention for patients with alcohol-induced liver damage. PMID:24650230

  18. Transdermal Delivery of Cannabidiol Attenuates Binge Alcohol-Induced Neurodegeneration in a Rodent Model of an Alcohol Use Disorder

    PubMed Central

    Liput, Daniel J.; Hammell, Dana C.; Stinchcomb, Audra L.; Nixon, Kimberly

    2013-01-01

    Excessive alcohol consumption, characteristic of alcohol use disorders, results in neurodegeneration and behavioral and cognitive impairments that are hypothesized to contribute to the chronic and relapsing nature of alcoholism. Therefore, the current study aimed to advance the preclinical development of transdermal delivery of cannabidiol (CBD) for the treatment of alcohol-induced neurodegeneration. In experiment 1, 1.0%, 2.5% and 5.0% CBD gels were evaluated for neuroprotection. The 5.0% CBD gel resulted in a 48.8% reduction in neurodegeneration in the entorhinal cortex assessed by Fluoro-Jade B (FJB), which trended to statistical significance (p = 0.069). Treatment with the 5.0% CBD gel resulted in day 3 CBD plasma concentrations of ~100.0 ng/mL so this level was used as a target concentration for development of an optimized gel formulation. Experiment 2 tested a next generation 2.5% CBD gel formulation, which was compared to CBD administration by intraperitoneal injection (IP; 40.0 mg/kg/d). This experiment found similar magnitudes of neuroprotection following both routes of administration; transdermal CBD decreased FJB+ cells in the entorhinal cortex by 56.1% (p < 0.05), while IP CBD resulted in a 50.6% (p < 0.05) reduction in FJB+ cells. These results demonstrate the feasibility of using CBD transdermal delivery systems for the treatment of alcohol-induced neurodegeneration. PMID:24012796

  19. The role of hypoxia in intestinal inflammation.

    PubMed

    Shah, Yatrik M

    2016-12-01

    Inflammatory bowel disease (IBD) is a chronic relapsing inflammatory disease of the intestine. IBD is a multifactorial disorder, and IBD-associated genes are critical in innate immune response, inflammatory response, autophagy, and epithelial barrier integrity. Moreover, epithelial oxygen tension plays a critical role in intestinal inflammation and resolution in IBD. The intestines have a dynamic and rapid fluctuation in cellular oxygen tension, which is dysregulated in IBD. Intestinal epithelial cells have a steep oxygen gradient where the tips of the villi are hypoxic and the oxygenation increases at the base of the villi. IBD results in heightened hypoxia throughout the mucosa. Hypoxia signals through a well-conserved family of transcription factors, where hypoxia-inducible factor (HIF)-1α and HIF-2α are essential in maintaining intestinal homeostasis. In inflamed mucosa, HIF-1α increases barrier protective genes, elicits protective innate immune responses, and activates an antimicrobial response through the increase in β-defensins. HIF-2α is essential in maintaining an epithelial-elicited inflammatory response and the regenerative and proliferative capacity of the intestine following an acute injury. HIF-1α activation in colitis leads to a protective response, whereas chronic activation of HIF-2α increases the pro-inflammatory response, intestinal injury, and cancer. In this mini-review, we detail the role of HIF-1α and HIF-2α in intestinal inflammation and injury and therapeutic implications of targeting HIF signaling in IBD. PMID:26812949

  20. OPG and RANKL polymorphisms are associated with alcohol-induced osteonecrosis of the femoral head in the north area of China population in men

    PubMed Central

    Li, Yizhou; Wang, Yuan; Guo, Yongchang; Wang, Quanjian; Ouyang, Yongri; Cao, Yuju; Jin, Tianbo; Wang, Jianzhong

    2016-01-01

    Abstract Alcohol-induced osteonecrosis of the femoral head (ONFH) is an important pathogenesis of nontraumatic ONFH. However, the mechanisms of the pathogenesis are still unknown. Osteoprotegerin (OPG) and receptor activator of nuclear factor-kappa B ligand (RANKL) have been implicated in multiple functions including blocking osteoclast maturation, controlling vascular calcifications, and promoting tumor growth and metastasis. The purpose of this article was to explore the association between OPG and RANKL gene variants and alcohol-induced ONFH. Six hundred seventy male subjects (335 patients and 335 normal individuals) were enrolled in our study. We selected 24 single-nucleotide polymorphisms (SNPs) to evaluate the association between genetic susceptibility variants and alcohol-induced ONFH using the chi-square test and gene model analysis. Overall, the OPG SNPs (rs1032128 and rs11573828) were associated with the strongest increased risk of alcohol-induced ONFH in the recessive model (rs1032128: odds ratio [OR] 1.49, 95% confidence interval [CI] 1.00–2.22, P = 0.04 for G/A; rs11573828: OR 3.32, 95% CI 1.07–10.30, P = 0.03 for T/C). The RANKL SNP rs2200287 was also an increased risk factor (OR 3.65, 95% CI 1.53–8.47, P = 0.003 for T/C) in the recessive model. The rs11573856, rs3134056, and rs1564861 SNPs were considered protective factors for alcohol-induced ONFH. We concluded that OPG and RANKL polymorphisms were associated with the occurrence of alcohol-induced ONFH. PMID:27336899

  1. Intestinal Obstruction

    MedlinePlus

    ... the small intestine (duodenum) may be caused by cancer of the pancreas, scarring from an ulcer, or Crohn disease . Rarely, a gallstone, a mass of undigested food, or a collection of parasitic worms may block ... commonly caused by cancer, diverticulitis , or a hard lump of stool (fecal ...

  2. [Intestinal endometriosis].

    PubMed

    González Rodríguez, C I; Cires, M; Jiménez, F J; Rubio, T

    2008-01-01

    Endometriosis is a chronic, benign gynaecological disorder that is frequent in women of a child-bearing age. It is estimated that there is some degree of endometriosis in as many as 15% of pre-menopausal women, associated with a history of infertility, caesarean antecedents, dysmenorrhoea and abnormality in uterine bleeding. It is believed to be due to the rise of menstrual contents through the Fallopian tubes (retrograde menstruation). In the intestinal affectation, the colon is the segment most frequently affected, above all at the rectosigmoidal level. The clinical features are unspecific, with abdominal pain the most frequent and/or pelvic pain of a cholic type that coincides with, or is exacerbated by, menstruation. Differential diagnosis includes intestinal inflammatory disease, diverticulitis, ischemic colitis and neoplastic processes, with the definitive diagnosis being anatomopathological. With respect to treatment, this will depend on the clinical features and the age of the patient, as well as her wishes with regard to pregnancy. PMID:18953367

  3. Performance measures of alcohol-induced impairment: towards a practical ignition-interlock system for motor vehicles.

    PubMed

    Matsumura, Kenta; Yamakoshi, Takehiro; Ida, Takayuki

    2009-12-01

    Performance-based alcohol screening devices may help reduce road traffic accidents, but there is a shortage of easy-to-use performance tests available. To address this issue, four recently developed rapid, computerized, easily implementable performance tests, Spiral for iPhone and Spiral for Mac (psychomotor tests), and the Modified Mental Rotation and Catch the Rabbit tests (cognitive tests), were assessed, testing participants at predrink baseline and then during three progressive amounts of alcohol intake. Analyses showed all tests were performed statistically significantly less accurately at 0.11% blood alcohol concentrations (BACs) than at 0.00% BAC, as were all tests except Spiral for iPhone at 0.06% BAC. These results indicate the suitability of all of these tests for measuring alcohol-induced impairment, and some potential for use as a practical performance-based alcohol screening device. PMID:20178284

  4. INTESTINAL OBSTRUCTION

    PubMed Central

    Cole, Warren H.

    1950-01-01

    Despite improvements in knowledge of the pathologic physiology of intestinal obstruction, the introduction of gastrointestinal decompression, and more effective antibiotics, obstruction remains a serious disease with a high mortality rate. Although the diagnosis is often obscure, it can usually be made with a fair degree of accuracy by the history alone; pain is fairly constant and characteristically is of a cramping type simulated by very few other lesions. Distention is present in low lesions but absent in high lesions; on the contrary, vomiting is minimal in low lesions but prominent in high lesions. Visible peristaltic waves are almost pathognomonic of intestinal obstruction. Increased peristaltic sounds, as noted by auscultation, are extremely helpful in diagnosis; they are absent in paralytic ileus. Although intestinal obstruction is a surgical lesion, it must be remembered that in the type produced by adhesions the obstruction can be relieved by gastrointestinal decompression in 80 to 90 per cent of cases. Operation is usually indicated a short time after relief because of the probability of recurrence. In practically all other types of obstruction decompression is indicated only while the patient is being prepared for operation. Obviously any type of strangulation demands early operation. Strangulation can usually be diagnosed, particularly if it develops while the patient is under observation. Increase in pain, muscle spasm and pulse rate are important indications of development of strangulation. Dehydration and electrolytic imbalance are produced almost universally in high obstruction. Usually, it is unwise to wait until these two deficiencies are corrected before operation is undertaken, but correction must be well under way at the time of operation. Resections should be avoided in the presence of intestinal obstruction, but obviously will be necessary in strangulation. Operative technique must be expert and carried out with minimal trauma. Postoperative

  5. Intestinal spirochaetosis

    PubMed Central

    Lee, F. D.; Kraszewski, A.; Gordon, J.; Howie, J. G. R.; McSeveney, D.; Harland, W. A.

    1971-01-01

    An abnormal condition of the large intestine is described in which the surface epithelium is infested by short spirochaetes. Diagnosis can be made by light microscopy. A review of 14 cases diagnosed by rectal biopsy and 62 cases involving the appendix shows no consistent symptom complex. The possible significance is discussed. ImagesFig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 1 PMID:5548558

  6. Small intestinal ischemia and infarction

    MedlinePlus

    ... small intestine; Atherosclerosis - small intestine; Hardening of the arteries - small intestine ... Embolus: Blood clots can block one of the arteries supplying the intestine. People who have had a ...

  7. Alcohol-induced heart rate response dampening during aversive and rewarding stress paradigms in subjects at risk for alcoholism.

    PubMed

    Croissant, Bernhard; Rist, Fred; Demmel, Ralf; Olbrich, Robert

    2006-08-01

    Individuals with a family history of alcoholism (FH+) are at risk to develop alcohol problems. In several studies, psychophysiological stress responses were more attenuated by alcohol in FH+ than in FH- subjects. However, it is not clear from these studies, if this stronger stress-response dampening effect of alcohol (SRD) in FH+ subjects is confined to aversive stimuli, or would hold for nonaversive stress conditions as well. Also, male and female FH+ subjects seem to respond differently to the alcohol challenge, but have rarely been directly compared in a SRD paradigm. Participants were 54 female and 63 male healthy adults; 31 women were daughters (DOAs) and 40 men were sons (SOAs) of alcohol-dependent fathers. The remaining 23 women (DONAs) and 23 men (SONAs) had no FH of any alcohol use disorder. The participants took part in two laboratory sessions, one with and one without alcohol. In each session, three stressor procedures were presented. Heart rate is the main dependent variable in this report. SOAs, but not SONAs showed a tendency towards SRD. Among female participants, a strong SRD occurred, but contrary to our expectation only in controls. Stress responses and SRD effects were somewhat stronger in the aversive than in the rewarding task. The extent of alcohol induced SRD was strongly influenced by BAL and the amplitude of the stress response in the no-alcohol condition (multiple regression analysis). Thus, aversive tasks might have the advantage of eliciting stronger stress responses than rewarding tasks, thereby providing better conditions for observing differences in alcohol induced SRD between FH+ and FH- subjects. PMID:16386812

  8. Hepatic Deficiency of Augmenter of Liver Regeneration Exacerbates Alcohol-Induced Liver Injury and Promotes Fibrosis in Mice.

    PubMed

    Kumar, Sudhir; Wang, Jiang; Rani, Richa; Gandhi, Chandrashekhar R

    2016-01-01

    Why only a subpopulation (about 15%) of humans develops liver cirrhosis due to alcohol is a critical as yet unanswered question. Liver-specific depletion of augmenter of liver regeneration (ALR) protein in mice causes robust steatosis and hepatocyte apoptosis by 2 weeks; these pathologies regress subsequently with return of ALR expression even at lower than control levels, but the mice develop modest steatohepatitis by 8 weeks. We aimed to investigate whether chronic alcohol ingestion promotes excessive hepatic fibrosis in these ALR-deficient mice. Liver-specific ALR-deficient and wild type (WT) female mice (8-10 weeks old) were placed on 4% alcohol-supplemented or isocaloric diet for 4 weeks. Liver sections were examined for histopathology, and parameters of steatosis and fibrosis were quantified. The mRNA expression of alcohol dehydrogenase-1, acetaldehyde dehydrogenase-1 and cytochrome P450-2E1 increased in WT mice but decreased in ALR-deficient mice upon alcohol ingestion. While alcohol induced steatosis and mild inflammation in WT mice, ALR-deficient mice showed minimal steatosis, strong hepatocellular injury and inflammation, prominent ductular proliferation, and robust fibrosis. Compared to the WT mice, alcohol feeding of ALR-deficient mice resulted in significantly greater increase in hepatic TNFα and TGFβ, and oxidative stress; there was also hepatic iron accumulation, robust lipid peroxidation and mitochondrial DNA damage. Importantly, similar to ALR-deficient mice, lower hepatic ALR levels in human alcoholic liver cirrhosis were associated with increased iron content, reduced expression of alcohol dehydrogenase and acetaldehyde dehydrogenase, and elevated fibrogenic markers. We conclude that ALR deficiency or anomaly can play a critical role in alcohol-induced hepatic fibrosis/cirrhosis, mechanisms of which may involve dysregulation of alcohol metabolism and iron homeostasis, mitochondrial damage and oxidative injury. PMID:26808690

  9. Alcohol-Induced Impairment in Adolescents Admitted to Inpatient Treatment After Heavy Episodic Drinking: Effects of Age and Gender

    PubMed Central

    Mick, Inge; Gross, Cornelius; Lachnit, Andreas; Kalkbrenner, Manja; Hoppe, Linda; Reichert, Jörg; Zimmermann, Ulrich S.

    2015-01-01

    Objective: In Germany and many other countries, the number of adolescent heavy episodic drinking–induced hospital admissions (HEDHA) in pediatric units markedly increased during the past decade. A low level of response to alcohol in young adults is associated with high risk for later development of alcohol use disorders (AUDs). Method: We performed a retrospective chart review of all 1,123 HEDHA cases in adolescents aged 11–17 years who were admitted to one of the pediatric inpatient units covering the cities of Dresden, Pirna, and Rostock, Germany, between 2000 and 2008. Blood alcohol concentration (BAC) and Glasgow Coma Scale (GCS) measures on admission were documented in 846 cases. Results: The mean (SD) BAC was 155 (50) mg/100 ml full blood, and M (SD) GCS was 12.21 (3.02). These parameters were negatively correlated with each other (r = -.256, p < .001), indicating more impairment at higher BACs. To describe a numerical estimate of how severely a subject was compromised relative to his BAC, the GCS scores were inverted (making high scores indicate severe impairment) and divided by BAC. The resulting alcohol-induced impairment index (AIII) was significantly influenced by an interaction between age and gender, decreasing with age in boys but increasing in girls. Conclusions: During adolescence, alcohol-induced impairment develops differently in boys and girls, which may be because of the girls’ developmental edge. The high variability of observed AIII might help to predict the risk for later AUDs in the emergency department, simply by measuring BAC and GCS. PMID:25978837

  10. Hepatic Deficiency of Augmenter of Liver Regeneration Exacerbates Alcohol-Induced Liver Injury and Promotes Fibrosis in Mice

    PubMed Central

    Kumar, Sudhir; Wang, Jiang; Rani, Richa; Gandhi, Chandrashekhar R.

    2016-01-01

    Why only a subpopulation (about 15%) of humans develops liver cirrhosis due to alcohol is a critical as yet unanswered question. Liver-specific depletion of augmenter of liver regeneration (ALR) protein in mice causes robust steatosis and hepatocyte apoptosis by 2 weeks; these pathologies regress subsequently with return of ALR expression even at lower than control levels, but the mice develop modest steatohepatitis by 8 weeks. We aimed to investigate whether chronic alcohol ingestion promotes excessive hepatic fibrosis in these ALR-deficient mice. Liver-specific ALR-deficient and wild type (WT) female mice (8–10 weeks old) were placed on 4% alcohol-supplemented or isocaloric diet for 4 weeks. Liver sections were examined for histopathology, and parameters of steatosis and fibrosis were quantified. The mRNA expression of alcohol dehydrogenase-1, acetaldehyde dehydrogenase-1 and cytochrome P450-2E1 increased in WT mice but decreased in ALR-deficient mice upon alcohol ingestion. While alcohol induced steatosis and mild inflammation in WT mice, ALR-deficient mice showed minimal steatosis, strong hepatocellular injury and inflammation, prominent ductular proliferation, and robust fibrosis. Compared to the WT mice, alcohol feeding of ALR-deficient mice resulted in significantly greater increase in hepatic TNFα and TGFβ, and oxidative stress; there was also hepatic iron accumulation, robust lipid peroxidation and mitochondrial DNA damage. Importantly, similar to ALR-deficient mice, lower hepatic ALR levels in human alcoholic liver cirrhosis were associated with increased iron content, reduced expression of alcohol dehydrogenase and acetaldehyde dehydrogenase, and elevated fibrogenic markers. We conclude that ALR deficiency or anomaly can play a critical role in alcohol-induced hepatic fibrosis/cirrhosis, mechanisms of which may involve dysregulation of alcohol metabolism and iron homeostasis, mitochondrial damage and oxidative injury. PMID:26808690

  11. Intestinal permeability defects: Is it time to treat?

    PubMed Central

    Odenwald, Matthew A.; Turner, Jerrold R.

    2013-01-01

    An essential role of the intestinal epithelium is to separate luminal contents from the interstitium, a function primarily determined by the integrity of the epithelium and the tight junction that seals the paracellular space. Intestinal tight junctions are selectively-permeable, and intestinal permeability can be increased physiologically in response to luminal nutrients or pathologically by mucosal immune cells and cytokines, the enteric nervous system, and pathogens. Compromised intestinal barrier function is associated with an array of clinical conditions, both intestinal and systemic. While most available data are correlative, some studies support a model where cycles of increased intestinal permeability, intestinal immune activation, and subsequent immune-mediated barrier loss contribute to disease progression. This model is applicable to intestinal and systemic diseases. However, it has not been proven and both mechanistic and therapeutic studies are ongoing. Nevertheless, the correlation between increased intestinal permeability and disease has caught the attention of the public, leading to a rise in popularity of the diagnosis of “leaky gut syndrome,” which encompasses a range of systemic disorders. Proponents claim that barrier restoration will cure underlying disease, but this has not been demonstrated in clinical trials. Moreover, human and mouse studies show that intestinal barrier loss alone is insufficient to initiate disease. It is therefore uncertain if increased permeability in these patients is a cause or effect of the underlying disorder. Although drug targets that may mediate barrier restoration have been proposed, none have been proven effective. As such, current treatments for barrier dysfunction should target the underlying disease. PMID:23851019

  12. Diet, Microbiome, and the Intestinal Epithelium: An Essential Triumvirate?

    PubMed Central

    Guzman, Javier Rivera; Conlin, Victoria Susan; Jobin, Christian

    2013-01-01

    The intestinal epithelium represents a critical barrier protecting the host against diverse luminal noxious agents, as well as preventing the uncontrolled uptake of bacteria that could activate an immune response in a susceptible host. The epithelial monolayer that constitutes this barrier is regulated by a meshwork of proteins that orchestrate complex biological function such as permeability, transepithelial electrical resistance, and movement of various macromolecules. Because of its key role in maintaining host homeostasis, factors regulating barrier function have attracted sustained attention from the research community. This paper will address the role of bacteria, bacterial-derived metabolism, and the interplay of dietary factors in controlling intestinal barrier function. PMID:23586037

  13. Large intestine (colon) (image)

    MedlinePlus

    The large intestine is the portion of the digestive system most responsible for absorption of water from the indigestible ... the ileum (small intestine) passes material into the large intestine at the cecum. Material passes through the ...

  14. Intestinal capillariasis.

    PubMed Central

    Cross, J H

    1992-01-01

    Intestinal capillariasis caused by Capillaria philippinensis appeared first in the Philippines and subsequently in Thailand, Japan, Iran, Egypt, and Taiwan, but most infections occur in the Philippines and Thailand. As established experimentally, the life cycle involves freshwater fish as intermediate hosts and fish-eating birds as definitive hosts. Embryonated eggs from feces fed to fish hatch and grow as larvae in the fish intestines. Infective larvae fed to monkeys, Mongolian gerbils, and fish-eating birds develop into adults. Larvae become adults in 10 to 11 days, and the first-generation females produce larvae. These larvae develop into males and egg-producing female worms. Eggs pass with the feces, reach water, embryonate, and infect fish. Autoinfection is part of the life cycle and leads to hyperinfection. Humans acquire the infection by eating small freshwater fish raw. The parasite multiplies, and symptoms of diarrhea, borborygmus, abdominal pain, and edema develop. Chronic infections lead to malabsorption and hence to protein and electrolyte loss, and death results from irreversible effects of the infection. Treatment consists of electrolyte replacement and administration of an antidiarrheal agent and mebendazole or albendazole. Capillariasis philippinensis is considered a zoonotic disease of migratory fish-eating birds. The eggs are disseminated along flyways and infect the fish, and when fish are eaten raw, the disease develops. Images PMID:1576584

  15. Epithelial CaSR Deficiency Alters Intestinal Integrity and Promotes Proinflammatory Immune Responses

    PubMed Central

    Cheng, Sam X.; Lightfoot, Yaíma L.; Yang, Tao; Zadeh, Mojgan; Tang, Lieqi; Sahay, Bikash; Wang, Gary P.; Owen, Jennifer L.; Mohamadzadeh, Mansour

    2014-01-01

    The intestinal epithelium is equipped with sensing receptor mechanisms that interact with luminal microorganisms and nutrients to regulate barrier function and gut immune responses, thereby maintaining intestinal homeostasis. Herein, we clarify the role of the extracellular calcium-sensing receptor (CaSR) using intestinal epithelium-specific Casr−/− mice. Epithelial CaSR deficiency diminished intestinal barrier function, altered microbiota composition, and skewed immune responses towards proinflammatory. Consequently, Casr−/− mice were significantly more prone to chemically induced intestinal inflammation resulting in colitis. Accordingly, CaSR represents a potential therapeutic target for autoinflammatory disorders, including inflammatory bowel diseases. PMID:24842610

  16. Cutaneous thermal injury alters macromolecular permeability of rat small intestine.

    PubMed

    Carter, E A; Tompkins, R G; Schiffrin, E; Burke, J F

    1990-03-01

    The intestinal epithelium normally provides a barrier function that prevents absorption of potentially harmful materials from the intestinal lumen. It has been postulated but never demonstrated that a cutaneous thermal injury will result in increased small-intestinal permeability. In a standardized 20% body surface area full-thickness scald injury, with polyethylene glycol 3350 and horseradish peroxidase used as permeability probes, small-intestinal permeability was examined regionally in an everted intestinal sac model. In the normal animals, the upper (proximal) and lower (distal) small intestine were less permeable to these probes than the middle segment. Within 6 hours after the injury, an increase in the mucosal uptake and transmural permeability was seen in all three small-intestinal segments; the most dramatic increase in permeability occurred in the ileum, p less than 0.01. The maximum increase in permeability was seen at 18 hours, and permeability was normal by 72 hours after the injury. This increase in intestinal permeability may represent a transient failure of the intestinal barrier function and may allow absorption of potentially toxic macromolecules from the intestinal lumen into the portal circulation early after thermal injury. Absorption of these macromolecules, such as endotoxin, may be potentially harmful by direct toxic actions or potentially helpful by activation of the immune system. PMID:2309150

  17. Importance of genetics in fetal alcohol effects: null mutation of the nNOS gene worsens alcohol-induced cerebellar neuronal losses and behavioral deficits

    PubMed Central

    Bonthius, Daniel J.; Winters, Zachary; Karacay, Bahri; Bousquet, Samantha Larimer; Bonthius, Daniel J.

    2014-01-01

    The cerebellum is a major target of alcohol-induced damage in the developing brain. However, the cerebella of some children are much more seriously affected than others by prenatal alcohol exposure. As a consequence of in utero alcohol exposure, some children have substantial reductions in cerebellar volume and corresponding neurodevelopmental problems, including microencephaly, ataxia, and balance deficits, while other children who were exposed to similar alcohol quantities are spared. One factor that likely plays a key role in determining the impact of alcohol on the fetal cerebellum is genetics. However, no specific gene variant has yet been identified that worsens cerebellar function as a consequence of developmental alcohol exposure. Previous studies have revealed that mice carrying a homozygous mutation of the gene for neuronal nitric oxide synthase (nNOS−/− mice) have more severe acute alcohol-induced neuronal losses from the cerebellum than wild type mice. Therefore, the goals of this study were to determine whether alcohol induces more severe cerebellum-based behavioral deficits in nNOS−/− mice than in wild type mice and to determine whether these worsened behavior deficits are associated with worsened cerebellar neuronal losses. nNOS−/− mice and their wild type controls received alcohol (0.0, 2.2, or 4.4 mg/g) daily over postnatal days 4–9. In adulthood, the mice underwent behavioral testing, followed by neuronal quantification. Alcohol caused dose-related deficits in rotarod and balance beam performance in both nNOS−/− and wild type mice. However, the alcohol-induced behavioral deficits were substantially worse in the nNOS−/− mice than in wild type. Likewise, alcohol exposure led to losses of Purkinje cells and cerebellar granule cells in mice of both genotypes, but the cell losses were more severe in the nNOS−/− mice than in wild type. Behavioral performances were correlated with neuronal number in the nNOS−/− mice, but not

  18. Epithelial Cell Shedding and Barrier Function

    PubMed Central

    Williams, J. M.; Duckworth, C. A.; Burkitt, M. D.; Watson, A. J. M.; Campbell, B. J.

    2015-01-01

    The intestinal epithelium is a critical component of the gut barrier. Composed of a single layer of intestinal epithelial cells (IECs) held together by tight junctions, this delicate structure prevents the transfer of harmful microorganisms, antigens, and toxins from the gut lumen into the circulation. The equilibrium between the rate of apoptosis and shedding of senescent epithelial cells at the villus tip, and the generation of new cells in the crypt, is key to maintaining tissue homeostasis. However, in both localized and systemic inflammation, this balance may be disturbed as a result of pathological IEC shedding. Shedding of IECs from the epithelial monolayer may cause transient gaps or microerosions in the epithelial barrier, resulting in increased intestinal permeability. Although pathological IEC shedding has been observed in mouse models of inflammation and human intestinal conditions such as inflammatory bowel disease, understanding of the underlying mechanisms remains limited. This process may also be an important contributor to systemic and intestinal inflammatory diseases and gut barrier dysfunction in domestic animal species. This review aims to summarize current knowledge about intestinal epithelial cell shedding, its significance in gut barrier dysfunction and host-microbial interactions, and where research in this field is directed. PMID:25428410

  19. The Protective Effect of Agaricus blazei Murrill, Submerged Culture Using the Optimized Medium Composition, on Alcohol-Induced Liver Injury

    PubMed Central

    Wang, Hang; Li, Gang; Zhang, Wenyu; Han, Chunchao; Xu, Xin; Li, Yong-Ping

    2014-01-01

    Agaricus blazei Murrill (ABM), an edible mushroom native to Brazil, is widely used for nonprescript and medicinal purposes. Alcohol liver disease (ALD) is considered as a leading cause for a liver injury in modern dietary life, which can be developed by a prolonged or large intake of alcohol. In this study, the medium composition of ABM was optimized using response surface methodology for maximum mycelial biomass and extracellular polysaccharide (EPS) production. The model predicts to gain a maximal mycelial biomass and extracellular polysaccharide at 1.047 g/100 mL, and 0.367 g/100 mL, respectively, when the potato is 29.88 g/100 mL, the glucose is 1.01 g/100 mL, and the bran is 1.02 g/100 mL. The verified experiments showed that the model was significantly consistent with the model prediction and that the trends of mycelial biomass and extracellular polysaccharide were predicted by artificial neural network. After that, the optimized medium was used for the submerged culture of ABM. Then, alcohol-induced liver injury in mice model was used to examine the protective effect of ABM cultured using the optimized medium on the liver. And the hepatic histopathological observations showed that ABM had a relatively significant role in mice model, which had alcoholic liver damage. PMID:25114908

  20. αCaMKII autophosphorylation controls the establishment of alcohol-induced conditioned place preference in mice.

    PubMed

    Easton, Alanna C; Lucchesi, Walter; Mizuno, Keiko; Fernandes, Cathy; Schumann, Gunter; Giese, K Peter; Müller, Christian P

    2013-09-01

    The autophosphorylation of alpha Ca2+ /calmodulin dependent protein kinase II (αCaMKII) is important for memory formation and is becoming increasingly implicated in the development of drug addiction. Previous work suggests that αCaMKII acts via the monoaminergic systems to facilitate the establishment of alcohol drinking behaviour. The present study aims to investigate whether αCaMKII autophosphorylation deficient αCaMKII(T286A) mice show a difference in the rewarding properties of alcohol (2 g/kg, i.p.), as measured by conditioned place preference (CPP). We found that alcohol-induced CPP could be established at an accelerated rate in αCaMKII(T286A) compared to wild type (WT) mice. Hyperactivity/hyper-arousal induced by the test environment was normalised by alcohol in the αCaMKII(T286A), but not WT mice. This effect could be conditioned to the test environment and may suggest enhanced negative reinforcing action of alcohol in αCaMKII autophosphorylation deficient mice. PMID:23732653

  1. Protective effect of Zhuyeqing liquor, a Chinese traditional health liquor, on acute alcohol-induced liver injury in mice

    PubMed Central

    2013-01-01

    The study first evaluated the hepatoprotective effect of Zhuyeqing Liquor (ZYQL) against acute alcohol-induced liver injury in mice. Animals were administered orally with 50% alcohol 12 ml/kg at 4 h after the doses of ZYQL everyday for fourteen consecutive days except mice in normal group. The protective effect was evaluated by biochemical parameters including serum aspartate transaminase (AST), alanine transferase (ALT), total-bilirubin (TBIL) and reduced glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD) in liver tissue. The result were confirmed histopathologically and the expression of TNF-α in mice liver was determined by immunohistochemistry analysis. HPLC-PDA was used for phytochemical analysis of ZYQL, and the plant source of each compound was claritied by UPLC-TOF-MS. The result showed that pretreatment with ZYQL exhibited a significant protective effect by reversing the biochemical parameters and histopathological changes in a dose depended manner. HPLC analysis indicated that ZYQL contained flavonoids, iridoids, terpenoids and phenolic acids, which might be the active chemicals. This study demonstrated the hepatoprotective activity of ZYQL, thus scientifically supported the function of its health care. PMID:24090365

  2. Gentiana manshurica Kitagawa reverses acute alcohol-induced liver steatosis through blocking sterol regulatory element-binding protein-1 maturation.

    PubMed

    Lian, Li-Hua; Wu, Yan-Ling; Song, Shun-Zong; Wan, Ying; Xie, Wen-Xue; Li, Xin; Bai, Ting; Ouyang, Bing-Qing; Nan, Ji-Xing

    2010-12-22

    This study was undertaken to investigate the protective effects of Gentiana manshurica Kitagawa (GM) on acute alcohol-induced fatty liver. Mice were treated with ethanol (5 g/kg of body weight) by gavage every 12 h for a total of three doses to induce acute fatty liver. Methanol extract of GM (50, 100, or 200 mg/kg) or silymarin (100 mg/kg) was gavaged simultaneously with ethanol for three doses. GM administration significantly reduced the increases in serum ALT and AST levels, the serum and hepatic triglyceride levels, at 4 h after the last ethanol administration. GM was also found to prevent ethanol-induced hepatic steatosis and necrosis, as indicated by liver histopathological studies. Additionally, GM suppressed the elevation of malondialdehyde (MDA) levels, restored the glutathione (GSH) levels, and enhanced the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities. The concurrent administration of GM efficaciously abrogated cytochrome P450 2E1 (CYP2E1) induction. Moreover, GM significantly reduced the nuclear translocation of sterol regulatory element-binding protein-1 (nSREBP-1) in ethanol-treated mice. These data indicated that GM possessed the ability to prevent ethanol-induced acute liver steatosis, possibly through blocking CYP2E1-mediated free radical scavenging effects and SREBP-1-regulated fatty acid synthesis. Especially, GM may be developed as a potential therapeutic candidate for ethanol-induced oxidative damage in liver. PMID:21105651

  3. Downregulation of the small GTPase SAR1A: a key event underlying alcohol-induced Golgi fragmentation in hepatocytes

    PubMed Central

    Petrosyan, Armen; Cheng, Pi-Wan; Clemens, Dahn L.; Casey, Carol A.

    2015-01-01

    The hepatic asialoglycoprotein receptor (ASGP-R) is posttranslationally modified in the Golgi en route to the plasma membrane, where it mediates clearance of desialylated serum glycoproteins. It is known that content of plasma membrane-associated ASGP-R is decreased after ethanol exposure, although the mechanisms remain elusive. Previously, we found that formation of compact Golgi requires dimerization of the largest Golgi matrix protein giantin. We hypothesize that ethanol-impaired giantin function may be related to altered trafficking of ASGP-R. Here we report that in HepG2 cells expressing alcohol dehydrogenase and hepatocytes of ethanol-fed rats, ethanol metabolism results in Golgi disorganization. This process is initiated by dysfunction of SAR1A GTPase followed by altered COPII vesicle formation and impaired Golgi delivery of the protein disulfide isomerase A3 (PDIA3), an enzyme that catalyzes giantin dimerization. Additionally, we show that SAR1A gene silencing in hepatocytes mimics the effect of ethanol: dedimerization of giantin, arresting PDIA3 in the endoplasmic reticulum (ER) and large-scale alterations in Golgi architecture. Ethanol-induced Golgi fission has no effect on ER-to-Golgi transportation of ASGP-R, however, it results in its deposition in cis-medial-, but not trans-Golgi. Thus, alcohol-induced deficiency in COPII vesicle formation predetermines Golgi fragmentation which, in turn, compromises the Golgi-to-plasma membrane transportation of ASGP-R. PMID:26607390

  4. Alcohol-induced persistent mild cognitive impairment with successful withdrawal from alcohol dependence--a case report.

    PubMed

    Harada, Toshihide; Ishizaki, Fumiko; Horie, Nobuko; Katsuoka, Hiroyuki; Nitta, Yumiko; Yamada, Tohru; Nitta, Kohsaku; Ito, Makoto

    2011-03-01

    An 81-year-old man diagnosed with alcohol-induced persistent mild cognitive impairment consulted our clinic presenting with gait disturbance. Between the ages of 20 and 53 years, his alcohol consumption was 1.8 liters of alcoholic sake per day. However, from the age of 53 years onward, his consumption decreased to 360 ml per day. The patient had alcoholic neuropathy, mild cognitive impairment, and alcoholic cerebellar disorder. His score on the revised version of Hasegawa's Dementia Scale (HDS-R) was 22 and his clinical dementia rating (CDR) was 0.5. His score on the Japanese version of the Mini-Mental State Examination (MMSE) was 22. These scores indicated mild cognitive impairment (MCI). He had delusions and confabulations, without impairment of date and place orientation. Magnetic resonance imaging (MRI) demonstrated enlarged ventricles, sulcal widening, and brain atrophy. He was provided with medication and counseling to treat his alcohol abuse. He accepted our treatment and is presently doing well after 1 year 2 months of treatment. PMID:21675042

  5. Diffusion barriers

    NASA Technical Reports Server (NTRS)

    Nicolet, M. A.

    1983-01-01

    The choice of the metallic film for the contact to a semiconductor device is discussed. One way to try to stabilize a contact is by interposing a thin film of a material that has low diffusivity for the atoms in question. This thin film application is known as a diffusion barrier. Three types of barriers can be distinguished. The stuffed barrier derives its low atomic diffusivity to impurities that concentrate along the extended defects of a polycrystalline layer. Sacrificial barriers exploit the fact that some (elemental) thin films react in a laterally uniform and reproducible fashion. Sacrificial barriers have the advantage that the point of their failure is predictable. Passive barriers are those most closely approximating an ideal barrier. The most-studied case is that of sputtered TiN films. Stuffed barriers may be viewed as passive barriers whose low diffusivity material extends along the defects of the polycrystalline host.

  6. Non-invasive assessment of barrier integrity and function of the human gut

    PubMed Central

    Grootjans, Joep; Thuijls, Geertje; Verdam, Froukje; Derikx, Joep PM; Lenaerts, Kaatje; Buurman, Wim A

    2010-01-01

    Over the past decades evidence has been accumulating that intestinal barrier integrity loss plays a key role in the development and perpetuation of a variety of disease states including inflammatory bowel disease and celiac disease, and is a key player in the onset of sepsis and multiple organ failure in situations of intestinal hypoperfusion, including trauma and major surgery. Insight into gut barrier integrity and function loss is important to improve our knowledge on disease etiology and pathophysiology and contributes to early detection and/or secondary prevention of disease. A variety of tests have been developed to assess intestinal epithelial cell damage, intestinal tight junction status and consequences of intestinal barrier integrity loss, i.e. increased intestinal permeability. This review discusses currently available methods for evaluating loss of human intestinal barrier integrity and function. PMID:21160852

  7. Strengthening of the intestinal epithelial tight junction by Bifidobacterium bifidum

    PubMed Central

    Hsieh, Chen-Yu; Osaka, Toshifumi; Moriyama, Eri; Date, Yasuhiro; Kikuchi, Jun; Tsuneda, Satoshi

    2015-01-01

    Epithelial barrier dysfunction has been implicated as one of the major contributors to the pathogenesis of inflammatory bowel disease. The increase in intestinal permeability allows the translocation of luminal antigens across the intestinal epithelium, leading to the exacerbation of colitis. Thus, therapies targeted at specifically restoring tight junction barrier function are thought to have great potential as an alternative or supplement to immunology-based therapies. In this study, we screened Bifidobacterium, Enterococcus, and Lactobacillus species for beneficial microbes to strengthen the intestinal epithelial barrier, using the human intestinal epithelial cell line (Caco-2) in an in vitro assay. Some Bifidobacterium and Lactobacillus species prevented epithelial barrier disruption induced by TNF-α, as assessed by measuring the transepithelial electrical resistance (TER). Furthermore, live Bifidobacterium species promoted wound repair in Caco-2 cell monolayers treated with TNF-α for 48 h. Time course 1H-NMR-based metabonomics of the culture supernatant revealed markedly enhanced production of acetate after 12 hours of coincubation of B. bifidum and Caco-2. An increase in TER was observed by the administration of acetate to TNF-α-treated Caco-2 monolayers. Interestingly, acetate-induced TER-enhancing effect in the coculture of B. bifidum and Caco-2 cells depends on the differentiation stage of the intestinal epithelial cells. These results suggest that Bifidobacterium species enhance intestinal epithelial barrier function via metabolites such as acetate. PMID:25780093

  8. Geniposide protects against acute alcohol-induced liver injury in mice via up-regulating the expression of the main antioxidant enzymes.

    PubMed

    Wang, Junming; Zhang, Yueyue; Liu, Ruixin; Li, Xiaobing; Cui, Ying; Qu, Lingbo

    2015-04-01

    Geniposide (GP) is one of main compounds in Gardenia jasminoides Ellis, with both medicinal and nutritional value. This study was designed to determine, for the first time, how GP from G. jasminoides protects against acute alcohol-induced liver injury, and the underlying mechanisms. Mice were orally administered alcohol (6.0 g/kg body mass) 2 h after intragastric administration of GP and bifendate, every day for 7 continuous days. Six hours after the alcohol was administered, levels of serum alanine/aspartate transaminase (ALT/AST), hepatic lipid peroxidation (LPO), glutathione (GSH), glutathione-S-transferase (GST), glutathione peroxidase (GPx), copper- and zinc-containing superoxide dismutase (CuZn-SOD), and catalase (CAT), and mRNA expression of CuZn-SOD and CAT were assayed. The results demonstrated that GP (20.0, 40.0, or 80 mg/kg) significantly reversed the excessive, alcohol-induced elevation in both serum ALT/AST and hepatic LPO levels. Moreover, hepatic GSH, GST, GPx, CuZn-SOD, and CAT levels were all decreased in the alcohol-treated mice, whereas treatment with GP reversed these decreases. Further analysis indicated that hepatic mRNA expression of CuZn-SOD and CAT in the alcohol-treated mice was significantly down-regulated, whereas GP up-regulated such decreases. Taken together, this study shows that GP protects against acute alcohol-induced liver injury via up-regulating the expression of the main antioxidant enzymes, and thus ameliorates alcohol-induced oxidative stress injury in the liver. PMID:25730420

  9. A novel peptide, colivelin, prevents alcohol-induced apoptosis in fetal brain of C57BL/6 mice: signaling pathway investigations

    PubMed Central

    Sari, Youssef; Chiba, Tomohiro; Yamada, Marina; Rebec, George V.; Aiso, Sadakazu

    2009-01-01

    Fetal alcohol exposure is known to induce cell death through apoptosis. We found that colivelin (CLN), a novel peptide with the sequence SALLRSIPAPAGASRLLLLTGEIDLP, prevents this apoptosis. Our initial experiment revealed that CLN enhanced the viability of primary cortical neurons exposed to alcohol. We then used a mouse model of fetal alcohol exposure to identify the intracellular mechanisms underlying these neuroprotective effects. On embryonic day 7 (E7), weight-matched pregnant females were assigned to the following groups: (1) ethanol liquid diet (ALC) 25% (4.49%, v/v) ethanol derived calories; (2) pair-fed control; (3) normal chow; (4) ALC combined with administration (i.p.) of CLN (20 μg/20 g body weight); and (5) pair-fed combined with administration (i.p.) of CLN (20 μg/20 g body weight). On E13, fetal brains were collected and assayed for TUNEL staining, caspase-3 colorimetric assay, ELISA, and MSD electrochemiluminescence. CLN blocked the alcohol-induced decline in brain weight and prevented alcohol-induced: apoptosis, activation of caspase-3 and increases of cytosolic cytochrome c, and decreases of mitochondrial cytochrome c. Analysis of proteins in the upstream signaling pathway revealed that CLN down-regulated the phosphorylation of the c-Jun N-terminal kinase. Moreover, CLN prevented alcohol-induced reduction in phosphorylation of BAD protein. Thus, CLN appears to act directly on upstream signaling proteins to prevent alcohol-induced apoptosis. Further assessment of these proteins and their signaling mechanisms is likely to enhance development of neuroprotective therapies. PMID:19782727

  10. Dysregulation of hepatic cAMP levels via altered Pde4b expression plays a critical role in alcohol-induced steatosis.

    PubMed

    Avila, Diana V; Barker, David F; Zhang, JingWen; McClain, Craig J; Barve, Shirish; Gobejishvili, Leila

    2016-09-01

    Alcohol-induced hepatic steatosis is a significant risk factor for progressive liver disease. Cyclic adenosine monophosphate (cAMP) signalling has been shown to significantly regulate lipid metabolism; however, the role of altered cAMP homeostasis in alcohol-mediated hepatic steatosis has never been studied. Our previous work demonstrated that increased expression of hepatic phosphodiesterase 4 (Pde4), which specifically hydrolyses and decreases cAMP levels, plays a pathogenic role in the development of liver inflammation/injury. The aim of this study was to examine the role of PDE4 in alcohol-induced hepatic steatosis. C57BL/6 wild-type and Pde4b knockout (Pde4b(-/-) ) mice were pair-fed control or ethanol liquid diets. One group of wild-type mice received rolipram, a PDE4-specific inhibitor, during alcohol feeding. We demonstrate for the first time that an early increase in PDE4 enzyme expression and a resultant decrease in hepatic cAMP levels are associated with the significant reduction in carnitine palmitoyltransferase 1A (Cpt1a) expression. Notably, alcohol-fed (AF) Pde4b(-/-) mice and AF wild-type mice treated with rolipram had significantly lower hepatic free fatty acid content compared with AF wild-type mice. Importantly, PDE4 inhibition in alcohol-fed mice prevented the decrease in hepatic Cpt1a expression via the Pparα/Sirt1/Pgc1α pathway. These results demonstrate that the alcohol- induced increase in hepatic Pde4, specifically Pde4b expression, and compromised cAMP signalling predispose the liver to impaired fatty acid oxidation and the development of steatosis. Moreover, these data also suggest that hepatic PDE4 may be a clinically relevant therapeutic target for the treatment of alcohol-induced hepatic steatosis. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:27287961

  11. Antigen sampling in the fish intestine.

    PubMed

    Løkka, Guro; Koppang, Erling Olaf

    2016-11-01

    Antigen uptake in the gastrointestinal tract may induce tolerance, lead to an immune response and also to infection. In mammals, most pathogens gain access to the host though the gastrointestinal tract, and in fish as well, this route seems to be of significant importance. The epithelial surface faces a considerable challenge, functioning both as a barrier towards the external milieu but simultaneously being the site of absorption of nutrients and fluids. The mechanisms allowing antigen uptake over the epithelial barrier play a central role for maintaining the intestinal homeostasis and regulate appropriate immune responses. Such uptake has been widely studied in mammals, but also in fish, a number of experiments have been reported, seeking to reveal cells and mechanisms involved in antigen sampling. In this paper, we review these studies in addition to addressing our current knowledge of the intestinal barrier in fish and its anatomical construction. PMID:26872546

  12. ACTIVITY-DEPENDENT NEUROPROTECTIVE PROTEIN–DERIVED PEPTIDE, NAP, PREVENTING ALCOHOL-INDUCED APOPTOSIS IN FETAL BRAIN OF C57BL/6 MOUSE

    PubMed Central

    SARI, Y.

    2012-01-01

    Possible prevention of the effects of prenatal alcohol exposure has been investigated using peptides that were previously shown to be involved in neuroprotection both in vitro and in vivo. I focused in this study on investigating the neuro-protective effects of one of these peptides with regard to the determination of the downstream signaling pathways involved in neuroprotection. This peptide with the sequence NAPVSIPQ, known as NAP, a fragment of activity-dependent neuroprotective protein, demonstrated a potent protective effect against oxidative stress associated with alcohol exposure. On embryonic day 7 (E7), weight-matched C57BL/6 pregnant females were assigned the following groups: (1) Ethanol liquid diet group (ALC) 25% (4.49%, v/v) ethano-derived calories, (2) Pair-fed (PF) control group (3) Chow control group, (4) treatment groups with alcohol alongside i.p. injections of d-NAP (ALC/d-NAP, 20 or 30 μg/20 g body weight), (5) PF/d-NAP control group. On E13, fetal brains were collected and assayed for TdT-mediated dUTP nick end labeling (TUNEL) staining, caspase-3 colorimetric assay and ELISA for cytochrome c detection. My results show that NAP significantly prevented alcohol-induced weight reduction of the fetal brain. Apoptosis was determined by TUNEL staining; NAP administration significantly prevented alcohol-induced increases in TUNEL-positive cells in primordium cingulate cortex and basal ganglia eminence. The investigation of downstream signaling pathways involving NAP neuroprotection revealed that this peptide significantly prevented alcohol-induced increase in the concentrations of caspase-3 in E13 fetal brains. Moreover, ELISA for cytochrome c shows that NAP significantly prevented both alcohol-induced increases in the level of cytosolic cytochrome c and alcohol-induced decreases in the level of mitochondrial cytochrome c. These data provide an understanding of NAP intracellular target, and the downstream mechanisms of action that will pave a path

  13. Role of Hypoxia Inducing Factor-1β in Alcohol-Induced Autophagy, Steatosis and Liver Injury in Mice

    PubMed Central

    Ni, Hong-Min; Bhakta, Amar; Wang, Shaogui; Li, Zhenrui; Manley, Sharon; Huang, Heqing; Copple, Bryan; Ding, Wen-Xing

    2014-01-01

    Chronic alcohol causes liver hypoxia and steatosis, which eventually develops into alcoholic liver disease (ALD). While it has been known that alcohol consumption activates hepatic hypoxia inducing factor-1α (HIF-1α), conflicting results regarding the role of HIF-1α in alcohol-induced liver injury and steatosis in mice have been reported. In the present study, we aimed to use hepatocyte-specific HIF-1β knockout mice to eliminate the possible compensatory effects of the single knockout of the 1α subunit of HIF to study the role of HIFs in ALD. C57BL/6 wild type mice were treated with acute ethanol to mimic human binge drinking. Matched wild-type and hepatocyte specific HIF-1β knockout mice were also subjected to a recently established Gao-binge alcohol model to mimic chronic plus binge conditions, which is quite common in human alcoholics. We found that acute alcohol treatment increased BNIP3 and BNIP3L/NIX expression in primary cultured hepatocytes and in mouse livers, suggesting that HIF may be activated in these models. We further found that hepatocyte-specific HIF-1β knockout mice developed less steatosis and liver injury following the Gao-binge model or acute ethanol treatment compared with their matched wild type mice. Mechanistically, protection against Gao-binge treatment-induced steatosis and liver injury was likely associated with increased FoxO3a activation and subsequent induction of autophagy in hepatocyte-specific HIF-1β knockout mice. PMID:25536043

  14. Alcohol-Induced miR-27a Regulates Differentiation and M2 Macrophage Polarization of Normal Human Monocytes

    PubMed Central

    Saha, Banishree; Bruneau, Johanna C.; Kodys, Karen; Szabo, Gyongyi

    2015-01-01

    Alcohol abuse is a leading cause of liver disease characterized by liver inflammation, fatty liver, alcoholic hepatitis, or liver cirrhosis. Immunomodulatory effects of alcohol on monocytes and macrophages contribute to alcoholic liver disease. Alcohol use, an independent risk factor for progression of hepatitis C virus (HCV) infection–mediated liver disease, impairs host defense and alters cytokine production and monocyte/macrophage activation. We hypothesized that alcohol and HCV have synergistic effects on the phenotype and function of monocytes. Our data show that acute alcohol binge drinking in healthy volunteers results in increased frequency of CD16+ and CD68+ and M2-type (CD206+, dendritic cell [DC]-SIGN+–expressing and IL-10–secreting) circulating CD14+ monocytes. Expression of HCV-induced CD68 and M2 markers (CD206 and DC-SIGN) in normal monocytes was further enhanced in the presence of alcohol. The levels of microRNA (miR)-27a was significantly upregulated in monocytes cultured in the presence of alcohol or alcohol and HCV as compared with HCV alone. The functional role of miR-27a in macrophage polarization was demonstrated by transfecting monocytes with an miR-27a inhibitor that resulted in reduced alcohol- and HCV- mediated monocyte activation (CD14 and CD68 expression), polarization (CD206 and DC-SIGN expression), and IL-10 secretion. Over-expression of miR-27a in monocytes enhanced IL-10 secretion via activation of the ERK signaling pathway. We found that miR-27a promoted ERK phosphorylation by downregulating the expression of ERK inhibitor sprouty2 in monocytes. Thus, we identified that sprouty2 is a target of miR-27a in human monocytes. In summary, our study demonstrates the regulatory role of miR-27a in alcohol-induced monocyte activation and polarization. PMID:25716995

  15. Mechanism for benzyl alcohol-induced aggregation of recombinant human interleukin-1 receptor antagonist in aqueous solution.

    PubMed

    Zhang, Ye; Roy, Shouvik; Jones, Latoya S; Krishnan, Sampathkumar; Kerwin, Bruce A; Chang, Byeong S; Manning, Mark C; Randolph, Theodore W; Carpenter, John F

    2004-12-01

    Benzyl alcohol, an antimicrobial preservative, accelerates aggregation and precipitation of recombinant human interleukin-1 receptor antagonist (rhIL-1ra) in aqueous solution. The loss of native monomer during incubation at 37 degrees C was determined by analysis of sample aliquots with size exclusion high performance liquid chromatography (SE-HPLC). Benzyl alcohol caused minor perturbation of the tertiary structure of the protein without changing its secondary structure, documenting that the preservative caused a minor shift in the protein molecular population toward partially unfolded species. Consistent with this conclusion, in the presence of benzyl alcohol the rate of H-D exchange was accelerated and the fluorescence of 1-anilinonaphthalene-8-sulfonic acid in the presence of rhIL1ra was increased. Benzyl alcohol did not alter the free energy of unfolding based on unfolding experiments in urea or guanidine HCl. With differential scanning calorimetry it was determined that benzyl alcohol reduced the apparent Tm of rhIL-1ra, but this effect occurred because the preservative lowered the temperature at which the protein aggregated during heating. Isothermal calorimetry documented that the interaction of benzyl alcohol with rhIL-1ra is relatively weak and hydrophobically driven. Thus, benzyl alcohol accelerates protein aggregation by binding to the protein and favoring an increase in the level of partially unfolded, aggregation-competent species. Sucrose partially inhibited benzyl alcohol-induced aggregation and tertiary structural change. Sucrose is preferentially excluded from the surface of the protein, favoring most compact native state species over expanded aggregation-prone forms. PMID:15514986

  16. Increased Sensitivity to Binge Alcohol-Induced Gut Leakiness and Inflammatory Liver Disease in HIV Transgenic Rats

    PubMed Central

    Banerjee, Atrayee; Abdelmegeed, Mohamed A.; Jang, Sehwan; Song, Byoung-Joon

    2015-01-01

    The mechanisms of alcohol-mediated advanced liver injury in HIV-infected individuals are poorly understood. Thus, this study was aimed to investigate the effect of binge alcohol on the inflammatory liver disease in HIV transgenic rats as a model for simulating human conditions. Female wild-type (WT) or HIV transgenic rats were treated with three consecutive doses of binge ethanol (EtOH) (3.5 g/kg/dose oral gavages at 12-h intervals) or dextrose (Control). Blood and liver tissues were collected at 1 or 6-h following the last dose of ethanol or dextrose for the measurements of serum endotoxin and liver pathology, respectively. Compared to the WT, the HIV rats showed increased sensitivity to alcohol-mediated gut leakiness, hepatic steatosis and inflammation, as evidenced with the significantly elevated levels of serum endotoxin, hepatic triglycerides, histological fat accumulation and F4/80 staining. Real-time PCR analysis revealed that hepatic levels of toll-like receptor-4 (TLR4), leptin and the downstream target monocyte chemoattractant protein-1 (MCP-1) were significantly up-regulated in the HIV-EtOH rats, compared to all other groups. Subsequent experiments with primary cultured cells showed that both hepatocytes and hepatic Kupffer cells were the sources of the elevated MCP-1 in HIV-EtOH rats. Further, TLR4 and MCP-1 were found to be upregulated by leptin. Collectively, these results show that HIV rats, similar to HIV-infected people being treated with the highly active anti-retroviral therapy (HAART), are more susceptible to binge alcohol-induced gut leakiness and inflammatory liver disease than the corresponding WT, possibly due to additive or synergistic interaction between binge alcohol exposure and HIV infection. Based on these results, HIV transgenic rats can be used as a surrogate model to study the molecular mechanisms of many disease states caused by heavy alcohol intake in HIV-infected people on HAART. PMID:26484872

  17. Gut barrier function in malnourished patients

    PubMed Central

    Welsh, F; Farmery, S; MacLennan, K; Sheridan, M; Barclay, G; Guillou, P; Reynolds, J

    1998-01-01

    Background—The integrity of the gastrointestinal mucosa is a key element in preventing systemic absorption of enteric toxins and bacteria. In the critically ill, breakdown of gut barrier function may fuel sepsis. Malnourished patients have an increased risk of postoperative sepsis; however, the effects of malnutrition on intestinal barrier function in man are unknown. 
Aims—To quantify intestinal barrier function, endotoxin exposure, and the acute phase cytokine response in malnourished patients. 
Patients—Malnourished and well nourished hospitalised patients. 
Methods—Gastrointestinal permeability was measured in malnourished patients and well nourished controls using the lactulose:mannitol test. Endoscopic biopsy specimens were stained and morphological and immunohistochemical features graded. The polymerase chain reaction was used to determine mucosal cytokine expression. The immunoglobulin G antibody response to endotoxin and serum interleukin 6 were measured by enzyme linked immunosorbent assay. 
Results—There was a significant increase in intestinal permeability in the malnourished patients in association with phenotypic and molecular evidence of activation of lamina propria mononuclear cells and enterocytes, and a heightened acute phase response. 
Conclusions—Intestinal barrier function is significantly compromised in malnourished patients, but the clinical significance is unclear. 

 Keywords: protein-energy malnutrition; intestinal permeability; endotoxin; cytokine PMID:9577348

  18. When Insult Is Added to Injury: Cross Talk between ILCs and Intestinal Epithelium in IBD

    PubMed Central

    2016-01-01

    Inflammatory bowel disease (IBD) is characterized by an impairment of the integrity of the mucosal epithelial barrier, which causes exacerbated inflammation of the intestine. The intestinal barrier is formed by different specialized epithelial cells, which separate the intestinal lumen from the lamina propria. In addition to its crucial role in protecting the body from invading pathogens, the intestinal epithelium contributes to intestinal homeostasis by its biochemical properties and communication to underlying immune cells. Innate lymphoid cells (ILCs) are a recently described population of lymphocytes that have been implicated in both mucosal homeostasis and inflammation. Recent findings indicate a critical feedback loop in which damaged epithelium activates these innate immune cells to restore epithelial barrier function. This review will focus on the signalling pathways between damaged epithelium and ILCs involved in repair of the epithelial barrier and tissue homeostasis and the relationship of these processes with the control of IBD. PMID:27578924

  19. When Insult Is Added to Injury: Cross Talk between ILCs and Intestinal Epithelium in IBD.

    PubMed

    van der Gracht, Esmé; Zahner, Sonja; Kronenberg, Mitchell

    2016-01-01

    Inflammatory bowel disease (IBD) is characterized by an impairment of the integrity of the mucosal epithelial barrier, which causes exacerbated inflammation of the intestine. The intestinal barrier is formed by different specialized epithelial cells, which separate the intestinal lumen from the lamina propria. In addition to its crucial role in protecting the body from invading pathogens, the intestinal epithelium contributes to intestinal homeostasis by its biochemical properties and communication to underlying immune cells. Innate lymphoid cells (ILCs) are a recently described population of lymphocytes that have been implicated in both mucosal homeostasis and inflammation. Recent findings indicate a critical feedback loop in which damaged epithelium activates these innate immune cells to restore epithelial barrier function. This review will focus on the signalling pathways between damaged epithelium and ILCs involved in repair of the epithelial barrier and tissue homeostasis and the relationship of these processes with the control of IBD. PMID:27578924

  20. Vasoactive intestinal peptide test

    MedlinePlus

    ... medlineplus.gov/ency/article/003508.htm Vasoactive intestinal peptide test To use the sharing features on this page, please enable JavaScript. Vasoactive intestinal peptide (VIP) is a test that measures the amount ...

  1. The gut barrier: new acquisitions and therapeutic approaches.

    PubMed

    Scaldaferri, Franco; Pizzoferrato, Marco; Gerardi, Viviana; Lopetuso, Loris; Gasbarrini, Antonio

    2012-10-01

    The intestinal barrier serves 2 critical functions for the survival of the individual: first, it allows nutrient absorption and second, it defends the body from dangerous macromolecule penetration. It is a complex multilayer system, consisting of an external "anatomic" barrier and an inner "functional" immunological barrier. The interaction of these 2 barriers enables equilibrated permeability to be maintained. Many factors can alter this balance: gut microflora modifications, mucus layer alterations, and epithelial damage can increase intestinal permeability, allowing the translocation of luminal content to the inner layer of intestinal wall. Several techniques are now available that enable us to study gut permeability: "in vitro" models (Caco-2 and HT29-MTX cells) and "in vivo" not invasive tests (sugar tests and radioisotope scanning tests) are used to estimate permeability and to suggest molecular pathophysiological mechanisms of intestinal permeability in health and diseases. Many medicinal products used in the treatment of gastrointestinal diseases have also found to play an active role in modulate intestinal permeability: corticosteroids, 5-aminosalicylic acid, anti-tumor necrosis factor, probiotics, and mucosal protectors, like gelatin tannate. This review will particularly address the role of the gut barrier in maintaining intestinal permeability (microbiota, mucus, and epithelial cells), the techniques used for estimating intestinal permeability and the therapeutic approaches able to modify it. PMID:22955350

  2. Redox biology of the intestine

    PubMed Central

    Circu, Magdalena L.; Aw, Tak Yee

    2011-01-01

    The intestinal tract, known for its capability for self-renew, represents the first barrier of defense between the organism and its luminal environment. The thiol/disulfide redox systems comprising the glutathione/glutathione disulfide (GSH/GSSG), cysteine/cystine (Cys/CySS) and reduced and oxidized thioredoxin (Trx/TrxSS) redox couples play important roles in preserving tissue redox homeostasis, metabolic functions, and cellular integrity. Control of the thiol-disulfide status at the luminal surface is essential for maintaining mucus fluidity and absorption of nutrients, and protection against chemical-induced oxidant injury. Within intestinal cells, these redox couples preserve an environment that supports physiological processes and orchestrates networks of enzymatic reactions against oxidative stress. In this review, we focus on the intestinal redox and antioxidant systems, their subcellular compartmentation, redox signaling and epithelial turnover, and contribution of luminal microbiota, key aspects that are relevant to understanding redox-dependent processes in gut biology with implications for degenerative digestive disorders, such as inflammation and cancer. PMID:21831010

  3. Intestinal cytochromes P450 regulating the intestinal microbiota and its probiotic profile

    PubMed Central

    Bezirtzoglou, Eugenia Elefterios Venizelos

    2012-01-01

    Cytochromes P450 (CYPs) enzymes metabolize a large variety of xenobiotic substances. In this vein, a plethora of studies were conducted to investigate their role, as cytochromes are located in both liver and intestinal tissues. The P450 profile of the human intestine has not been fully characterized. Human intestine serves primarily as an absorptive organ for nutrients, although it has also the ability to metabolize drugs. CYPs are responsible for the majority of phase I drug metabolism reactions. CYP3A represents the major intestinal CYP (80%) followed by CYP2C9. CYP1A is expressed at high level in the duodenum, together with less abundant levels of CYP2C8-10 and CYP2D6. Cytochromes present a genetic polymorphism intra- or interindividual and intra- or interethnic. Changes in the pharmacokinetic profile of the drug are associated with increased toxicity due to reduced metabolism, altered efficacy of the drug, increased production of toxic metabolites, and adverse drug interaction. The high metabolic capacity of the intestinal flora is due to its enormous pool of enzymes, which catalyzes reactions in phase I and phase II drug metabolism. Compromised intestinal barrier conditions, when rupture of the intestinal integrity occurs, could increase passive paracellular absorption. It is clear that high microbial intestinal charge following intestinal disturbances, ageing, environment, or food-associated ailments leads to the microbial metabolism of a drug before absorption. The effect of certain bacteria having a benefic action on the intestinal ecosystem has been largely discussed during the past few years by many authors. The aim of the probiotic approach is to repair the deficiencies in the gut flora and establish a protective effect. There is a tentative multifactorial association of the CYP (P450) cytochrome role in the different diseases states, environmental toxic effects or chemical exposures and nutritional status. PMID:23990816

  4. Vehicle barrier

    DOEpatents

    Hirsh, Robert A.

    1991-01-01

    A vehicle security barrier which can be conveniently placed across a gate opening as well as readily removed from the gate opening to allow for easy passage. The security barrier includes a barrier gate in the form of a cable/gate member in combination with laterally attached pipe sections fixed by way of the cable to the gate member and lateral, security fixed vertical pipe posts. The security barrier of the present invention provides for the use of cable restraints across gate openings to provide necessary security while at the same time allowing for quick opening and closing of the gate areas without compromising security.

  5. [Intestinal dysbacteriosis promotes intestinal intraepithelial T lymphocyte activation and proinflammatory cytokine secretion in mice].

    PubMed

    Luo, Xia; Luo, Shuang; Zheng, Yanyi; Wen, Ruyan; Deng, Xiangliang; Zhou, Lian

    2016-08-01

    Objective To study the effect of intestinal dysbacteriosis on mouse intestinal intraepithelial T lymphocytes (iIELs). Methods The intestinal dysbacteriosis was induced in mice by oral administration of ceftriaxone sodium. The iIELs were digested with ethylene diaminetetraacetic acid (EDTA) and DL-dithiothreitol (DTT). The phenotype of iIELs and the proportions of subsets of T cells were detected by flow cytometry; the concentrations of cytokines (IL-2, IL-6, IFN-γ) in the intestine were examined by ELISA; the intestinal bacteria were analyzed with selective medium and PCR. Results Compared with the control group, intestinal commensal bacteria in mice were significantly reduced after the administration of ceftriaxone sodium, but fungi and yeasts increased. The proportions of T cell subgroups in ilELs changed, in which the proportion of TCR γδ(+)T cells significantly increased, and the activated CD3(+)T, CD8(+)T and TCR γδ(+)T cells increased. The concentrations of IL-2, IL-6 and IFN-γ were significantly raised in the intestine. Conclusion The dysbacteriosis results in the decrease of commensal bacteria, the increase of the fungus, the damage of microbial barrier, the more activated T cells in ilELs and the promotion of proinflammatory cytokine secretion in the gut. This is probably one of the reasons for inflammatory bowel disease caused by dysbacteriosis. PMID:27412931

  6. Vertebrate Intestinal Endoderm Development

    PubMed Central

    Spence, Jason R.; Lauf, Ryan; Shroyer, Noah F.

    2010-01-01

    The endoderm gives rise to the lining of the esophagus, stomach and intestines, as well as associated organs. To generate a functional intestine, a series of highly orchestrated developmental processes must occur. In this review, we attempt to cover major events during intestinal development from gastrulation to birth, including endoderm formation, gut tube growth and patterning, intestinal morphogenesis, epithelial reorganization, villus emergence as well as proliferation and cytodifferentiation. Our discussion includes morphological and anatomical changes during intestinal development as well as molecular mechanisms regulating these processes. PMID:21246663

  7. Small intestinal permeability in older adults

    PubMed Central

    Valentini, Luzia; Ramminger, Sara; Haas, Verena; Postrach, Elisa; Werich, Martina; Fischer, André; Koller, Michael; Swidsinski, Alexander; Bereswill, Stefan; Lochs, Herbert; Schulzke, Jörg‐Dieter

    2014-01-01

    Abstract It is not yet clear whether intestinal mucosal permeability changes with advancing age in humans. This question is of high importance for drug and nutrition approaches for older adults. Our main objective was to answer the question if small intestinal barrier integrity deteriorates with healthy aging. We conducted a cross‐sectional study including the pooled data of 215 nonsmoking healthy adults (93 female/122 male), 84 of whom were aged between 60 and 82 years. After a 12‐h fast, all participants ingested 10 g of lactulose and 5 g of mannitol. Urine was collected for 5 h afterwards and analyzed for test sugars. The permeability index (PI = lactulose/mannitol) was used to assess small intestinal permeability. Low‐grade inflammation defined by high‐sensitivity C‐reactive protein ≥1 mL/L and kidney function (estimated glomerular filtration rate) were determined in the older age group. The PI was similar in older compared to younger adults (P =0.887). However, the urinary recovery of lactulose and mannitol was lower in the older adults and this change was neither associated with urinary volume nor glomerular filtration rate. The PI was not significantly correlated with low‐grade inflammation or presence of noninsulin‐dependent type 2 diabetes. However, it significantly deteriorated in the copresence of both conditions compared to low‐grade inflammation alone (P =0.043) or type 2 diabetes alone (P =0.015). Small intestinal mucosal barrier does not deteriorate with age per se. But low‐grade inflammation coupled with minor disease challenges, such as type 2 diabetes, can compromise the small intestinal barrier. PMID:24771689

  8. Establishment of Intestinal Bacteriology

    PubMed Central

    MITSUOKA, Tomotari

    2014-01-01

    Research on intestinal bacteria began around the end of the 19th century. During the last 5 decades of the 20th century, research on the intestinal microbiota made rapid progress. At first, in my work, I first developed a method of comprehensive analysis of the intestinal microbiota, and then I established classification and identification methods for intestinal anaerobes. Using these methods I discovered a number of ecological rules governing the intestinal microbiota and the role of the intestinl microbiota in health and disease. Moreover, using germfree animals, it was proven that the intestinal microbiota has a role in carcinogenesis and aging in the host. Thus, a new interdisciplinary field, “intestinal bacteriology” was established. PMID:25032084

  9. Diagnosis and treatment of small intestinal bacterial overgrowth.

    PubMed

    Ponziani, Francesca Romana; Gerardi, Viviana; Gasbarrini, Antonio

    2016-01-01

    A huge number of bacteria are hosted in the gastrointestinal tract, following a gradient increasing towards the colon. Gastric acid secretion and intestinal clearance provide the qualitative and quantitative partitioning of intestinal bacteria; small intestinal bacteria overgrowth (SIBO) occurs when these barrier mechanisms fail. Diagnosis of SIBO is challenging due to the low specificity of symptoms, the frequent association with other diseases of the gastrointestinal tract and the absence of optimal objective diagnostic tests. The therapeutic approach to SIBO is oriented towards resolving predisposing conditions, and is supported by antibiotic treatment to restore the normal small intestinal microflora and by modifications of dietary habits for symptomatic relief. In the near future, metagenomics and metabolomics will help to overcome the uncertainties of SIBO diagnosis and the pitfalls of therapeutic management, allowing the design of a personalized strategy based on the direct insight into the small intestinal microbial community. PMID:26636484

  10. Ascorbic acid supplementation down-regulates the alcohol induced oxidative stress, hepatic stellate cell activation, cytotoxicity and mRNA levels of selected fibrotic genes in guinea pigs.

    PubMed

    Abhilash, P A; Harikrishnan, R; Indira, M

    2012-02-01

    Both oxidative stress and endotoxins mediated immunological reactions play a major role in the progression of alcoholic hepatic fibrosis. Ascorbic acid has been reported to reduce alcohol-induced toxicity and ascorbic acid levels are reduced in alcoholics. Hence, we investigated the hepatoprotective action of ascorbic acid in the reversal of alcohol-induced hepatic fibrosis in male guinea pigs (n = 36), and it was compared with the animals abstenting from alcohol treatment. In comparison with the alcohol abstention group, there was a reduction in the activities of toxicity markers and levels of lipid and protein peroxidation products, expression of α-SMA, caspase-3 activity and mRNA levels of CYP2E1, TGF-β(1), TNF-α and α(1)(I) collagen in liver of the ascorbic acid-supplemented group. The ascorbic acid content in liver was significantly reduced in the alcohol-treated guinea pigs. But it was reversed to normal level in the ascorbic acid-supplemented group. The anti-fibrotic action of ascorbic acid in the rapid regression of alcoholic liver fibrosis may be attributed to decrease in the oxidative stress, hepatic stellate cells activation, cytotoxicity and mRNA expression of fibrotic genes CYP2E1, TGF-β(1), TNF-α and α(1) (I) collagen in hepatic tissues. PMID:22149461

  11. Fucoidan from Fucus vesiculosus protects against alcohol-induced liver damage by modulating inflammatory mediators in mice and HepG2 cells.

    PubMed

    Lim, Jung Dae; Lee, Sung Ryul; Kim, Taeseong; Jang, Seon-A; Kang, Se Chan; Koo, Hyun Jung; Sohn, Eunsoo; Bak, Jong Phil; Namkoong, Seung; Kim, Hyoung Kyu; Song, In Sung; Kim, Nari; Sohn, Eun-Hwa; Han, Jin

    2015-02-01

    Fucoidan is an l-fucose-enriched sulfated polysaccharide isolated from brown algae and marine invertebrates. In this study, we investigated the protective effect of fucoidan from Fucus vesiculosus on alcohol-induced murine liver damage. Liver injury was induced by oral administration of 25% alcohol with or without fucoidan (30 mg/kg or 60 mg/kg) for seven days. Alcohol administration increased serum aspartate aminotransferase and alanine aminotransferase levels, but these increases were suppressed by the treatment of fucoidan. Transforming growth factor beta 1 (TGF-β1), a liver fibrosis-inducing factor, was highly expressed in the alcohol-fed group and human hepatoma HepG2 cell; however, the increase in TGF-β1 expression was reduced following fucoidan administration. Treatment with fucoidan was also found to significantly reduce the production of inflammation-promoting cyclooygenase-2 and nitric oxide, while markedly increasing the expression of the hepatoprotective enzyme, hemeoxygenase-1, on murine liver and HepG2 cells. Taken together, the antifibrotic and anti-inflammatory effects of fucoidan on alcohol-induced liver damage may provide valuable insights into developing new therapeutics or interventions. PMID:25690093

  12. Biomimetic PVPA in vitro model for estimation of the intestinal drug permeability using fasted and fed state simulated intestinal fluids.

    PubMed

    Naderkhani, Elenaz; Vasskog, Terje; Flaten, Gøril Eide

    2015-06-20

    A prerequisite for successful oral drug therapy is the drug's ability to cross the gastrointestinal barrier. Considering the increasing number of new chemical entities in modern drug discovery, reliable and fast in vitro models are required for early and efficient prediction of intestinal permeability. To mimic the intestinal environment, use of biorelevant media may provide valuable information on in vivo drug permeation. The present study aims at improving the novel biomimetic phospholipid vesicle-based permeation assay's (PVPAbiomimetic) biorelevance by investigating the applicability of the biorelevant media; fasted state simulated intestinal fluid (FaSSIF) and fed state simulated intestinal fluid (FeSSIF). The FaSSIF and FeSSIF's influence on the permeability of the model drugs acyclovir, indomethacin, griseofulvin and nadolol was then assessed. The barriers' robustness in terms of storage stability was also evaluated. The barriers were found to maintain their integrity in presence of FaSSIF and FeSSIF. The model drugs showed changes in permeability in presence of the different simulated intestinal fluids that were in agreement with previous reports. Moreover, the barrier showed improved storage stability by maintaining its integrity for 6months. Altogether, this study moves the PVPAbiomimetic an important step towards a better in vitro permeability model for use in drug development. PMID:25840125

  13. Epithelial tight junctions in intestinal inflammation.

    PubMed

    Schulzke, Joerg D; Ploeger, Svenja; Amasheh, Maren; Fromm, Anja; Zeissig, Sebastian; Troeger, Hanno; Richter, Jan; Bojarski, Christian; Schumann, Michael; Fromm, Michael

    2009-05-01

    The epithelium in inflamed intestinal segments of patients with Crohn's disease is characterized by a reduction of tight junction strands, strand breaks, and alterations of tight junction protein content and composition. In ulcerative colitis, epithelial leaks appear early due to micro-erosions resulting from upregulated epithelial apoptosis and in addition to a prominent increase of claudin-2. Th1-cytokine effects by interferon-gamma in combination with TNFalpha are important for epithelial damage in Crohn's disease, while interleukin-13 (IL-13) is the key effector cytokine in ulcerative colitis stimulating apoptosis and upregulation of claudin-2 expression. Focal lesions caused by apoptotic epithelial cells contribute to barrier disturbance in IBD by their own conductivity and by confluence toward apoptotic foci or erosions. Another type of intestinal barrier defect can arise from alpha-hemolysin harboring E. coli strains among the physiological flora, which can gain pathologic relevance in combination with proinflammatory cytokines under inflammatory conditions. On the other hand, intestinal barrier impairment can also result from transcellular antigen translocation via an initial endocytotic uptake into early endosomes, and this is intensified by proinflammatory cytokines as interferon-gamma and may thus play a relevant role in the onset of IBD. Taken together, barrier defects contribute to diarrhea by a leak flux mechanism (e.g., in IBD) and can cause mucosal inflammation by luminal antigen uptake. Immune regulation of epithelial functions by cytokines may cause barrier dysfunction not only by tight junction impairments but also by apoptotic leaks, transcytotic mechanisms, and mucosal gross lesions. PMID:19538319

  14. Mouse models of intestinal inflammation and cancer.

    PubMed

    Westbrook, Aya M; Szakmary, Akos; Schiestl, Robert H

    2016-09-01

    Chronic inflammation is strongly associated with approximately one-fifth of all human cancers. Arising from combinations of factors such as environmental exposures, diet, inherited gene polymorphisms, infections, or from dysfunctions of the immune response, chronic inflammation begins as an attempt of the body to remove injurious stimuli; however, over time, this results in continuous tissue destruction and promotion and maintenance of carcinogenesis. Here, we focus on intestinal inflammation and its associated cancers, a group of diseases on the rise and affecting millions of people worldwide. Intestinal inflammation can be widely grouped into inflammatory bowel diseases (ulcerative colitis and Crohn's disease) and celiac disease. Long-standing intestinal inflammation is associated with colorectal cancer and small-bowel adenocarcinoma, as well as extraintestinal manifestations, including lymphomas and autoimmune diseases. This article highlights potential mechanisms of pathogenesis in inflammatory bowel diseases and celiac disease, as well as those involved in the progression to associated cancers, most of which have been identified from studies utilizing mouse models of intestinal inflammation. Mouse models of intestinal inflammation can be widely grouped into chemically induced models; genetic models, which make up the bulk of the studied models; adoptive transfer models; and spontaneous models. Studies in these models have lead to the understanding that persistent antigen exposure in the intestinal lumen, in combination with loss of epithelial barrier function, and dysfunction and dysregulation of the innate and adaptive immune responses lead to chronic intestinal inflammation. Transcriptional changes in this environment leading to cell survival, hyperplasia, promotion of angiogenesis, persistent DNA damage, or insufficient repair of DNA damage due to an excess of proinflammatory mediators are then thought to lead to sustained malignant transformation. With

  15. Lactobacillus rhamnosus CCFM1107 treatment ameliorates alcohol-induced liver injury in a mouse model of chronic alcohol feeding.

    PubMed

    Tian, Fengwei; Chi, Feifei; Wang, Gang; Liu, Xiaoming; Zhang, Qiuxiang; Chen, Yongquan; Zhang, Hao; Chen, Wei

    2015-12-01

    Lactobacillus rhamnosus CCFM1107 was screened for high antioxidative activity from 55 lactobacilli. The present study attempted to explore the protective properties of L. rhamnosus CCFM1107 in alcoholic liver injury. A mouse model was induced by orally feeding alcohol when simultaneously treated with L. rhamnosus CCFM1107, the drug Hu-Gan- Pian (HGP), L. rhamnosus GG (LGG), and L. plantarum CCFM1112 for 3 months. Biochemical analysis was performed for both serum and liver homogenate. Detailed intestinal flora and histological analyses were also carried out. Our results indicated that the administration of L. rhamnosus CCFM1107 significantly inhibited the increase in the levels of serum aminotransferase and endotoxin, as well as the levels of triglyceride (TG) and cholesterol (CHO) in the serum and in the liver. Glutathione (GSH), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were elevated while the levels of malondialdehyde (MDA) were decreased. The enteric dysbiosis caused by alcohol was restored by increasing the numbers of both lactobacilli and bifidobacteria and decreasing the numbers of both enterococci and enterobacter. Histological analysis confirmed the protective effect of L. rhamnosus CCFM1107. Compared with the other lactobacilli and to the drug Hu-Gan-Pian, there is a high chance that L. rhamnosus CCFM1107 provides protective effects on alcoholic liver injury by reducing oxidative stress and restoring the intestinal flora. PMID:26626356

  16. The complex task of measuring intestinal permeability in basic and clinical science.

    PubMed

    Galipeau, H J; Verdu, E F

    2016-07-01

    Intestinal permeability is a key feature of intestinal barrier function. Altered intestinal permeability is described in many chronic diseases and may be a risk factor for disease development and a target for emerging therapeutics. Thus, reliable and sensitive methods to measure intestinal permeability in both the clinical and preclinical setting are needed. There is currently a large array of tests to choose from, each with advantages and disadvantages. When possible, a combination of methods should be used. The choice of tests should be based on a deep understanding of intestinal barrier physiology and the recognition of their limitations. This mini-review will highlight the advantages and limitations associated with intestinal permeability tests and will identify current problems in the field and how they can be addressed in the future. PMID:27339216

  17. Intestinal lymphangiectasia in children

    PubMed Central

    Isa, Hasan M.; Al-Arayedh, Ghadeer G.; Mohamed, Afaf M.

    2016-01-01

    Intestinal lymphangiectasia (IL) is a rare disease characterized by dilatation of intestinal lymphatics. It can be classified as primary or secondary according to the underlying etiology. The clinical presentations of IL are pitting edema, chylous ascites, pleural effusion, acute appendicitis, diarrhea, lymphocytopenia, malabsorption, and intestinal obstruction. The diagnosis is made by intestinal endoscopy and biopsies. Dietary modification is the mainstay in the management of IL with a variable response. Here we report 2 patients with IL in Bahrain who showed positive response to dietary modification. PMID:26837404

  18. New Ways of Thinking about (and Teaching about) Intestinal Epithelial Function

    ERIC Educational Resources Information Center

    Barrett, Kim E.

    2008-01-01

    This article summarizes a presentation made at the Teaching Refresher Course of the American Physiological Society, which was held at the Experimental Biology meeting in 2007. The intestinal epithelium has important ion transport and barrier functions that contribute pivotally to normal physiological functioning of the intestine and other body…

  19. Biliary Mucosal Barrier and Microbiome

    PubMed Central

    Verdier, Julien; Luedde, Tom; Sellge, Gernot

    2015-01-01

    Background The biliary system is in continuous contact with the complex microbiota of the intestine. Microbial products have recently been proposed as potential triggers for biliary diseases. Methods The aim of this review is to provide a summary of the current knowledge regarding the role of the biliary and intestinal microbiome in biliary inflammatory diseases. Results Previously, it was suggested that the healthy biliary system is a sterile organ, while acute cholangitis and cholecystitis may occur from ascending infections. Although non-inflammatory biliary colonization by certain bacteria such as Salmonella spp. has been already recognized since several decades, human and animal studies indicated only very recently that the gallbladder harbors a complex microbiota also under non-pathologic conditions. Novel findings suggested that – similar to the situation in the intestine – the biliary mucosa features a chemical, mechanical, and immunological barrier, ensuring immunological tolerance against commensals. However, microbial triggers might influence acute and chronic inflammatory disease of the biliary system and the whole liver. Conclusion Although yet undefined, dysbiosis of the biliary or intestinal microbiota rather than a single microorganism may influence disease progression. PMID:26468308

  20. Bifidobacterium lactis 420 and fish oil enhance intestinal epithelial integrity in Caco-2 cells.

    PubMed

    Mokkala, Kati; Laitinen, Kirsi; Röytiö, Henna

    2016-03-01

    Increased intestinal permeability is a predisposing factor for low-grade inflammation-associated conditions, including obesity and type 2 diabetes. Dietary components may influence intestinal barrier integrity. We hypothesized that the dietary supplements Bifidobacterium lactis 420, Lactobacillus rhamnosus HN001, and fish oil have beneficial impacts on intestinal barrier integrity. In addition, we hypothesized that the coadministration of these components results in synergistic benefits to the integrity of the intestinal barrier. To study this, we investigated the impact of cell-free culture supernatant from dietary supplements B lactis 420 and L rhamnosus HN001, and fish oil, separately and in combination, on intestinal permeability in a CaCo-2 cell model. Administered separately, both B lactis 420 supernatant and fish oil significantly increased the integrity of the intestinal epithelial barrier, as determined by an increase in transepithelial electrical resistance (TEER), whereas L rhamnosus did not. The TEER increase with B lactis 420 was dose dependent. Interestingly, a combination of B lactis 420 supernatant and fish oil negated the increase in TEER of the single components. mRNA expression of tight junction proteins, measured by real-time quantitative polymerase chain reaction, was not altered, but the mRNA expression of myosin light chain kinase increased after fish oil treatment. To conclude, single dietary components, namely, B lactis 420 and fish oil, induced beneficial effects on intestinal barrier integrity in vitro, whereas a combination of 2 beneficial test compounds resulted in a null effect. PMID:26923511

  1. Fish Oil Enhances Recovery of Intestinal Microbiota and Epithelial Integrity in Chronic Rejection of Intestinal Transplant

    PubMed Central

    Li, Qiurong; Zhang, Qiang; Wang, Chenyang; Tang, Chun; Zhang, Yanmei; Li, Ning; Li, Jieshou

    2011-01-01

    Background The intestinal chronic rejection (CR) is the major limitation to long-term survival of transplanted organs. This study aimed to investigate the interaction between intestinal microbiota and epithelial integrity in chronic rejection of intestinal transplantation, and to find out whether fish oil enhances recovery of intestinal microbiota and epithelial integrity. Methods/Principal Findings The luminal and mucosal microbiota composition of CR rats were characterized by DGGE analysis at 190 days after intestinal transplant. The specific bacterial species were determined by sequence analysis. Furthermore, changes in the localization of intestinal TJ proteins were examined by immunofluorescent staining. PCR-DGGE analysis revealed that gut microbiota in CR rats had a shift towards Escherichia coli, Bacteroides spp and Clostridium spp and a decrease in the abundance of Lactobacillales bacteria in the intestines. Fish oil supplementation could enhance the recovery of gut microbiota, showing a significant decrease of gut bacterial proportions of E. coli and Bacteroides spp and an increase of Lactobacillales spp. In addition, CR rats showed pronounced alteration of tight junction, depicted by marked changes in epithelial cell ultrastructure and redistribution of occuldin and claudins as well as disruption in TJ barrier function. Fish oil administration ameliorated disruption of epithelial integrity in CR, which was associated with an improvement of the mucosal structure leading to improved tight junctions. Conclusions/Significance Our study have presented novel evidence that fish oil is involved in the maintenance of epithelial TJ integrity and recovery of gut microbiota, which may have therapeutic potential against CR in intestinal transplantation. PMID:21698145

  2. TLR2-independent induction and regulation of chronic intestinal inflammation.

    PubMed

    Boulard, Olivier; Asquith, Mark J; Powrie, Fiona; Maloy, Kevin J

    2010-02-01

    Interactions between the intestinal microflora and host innate immune receptors play a critical role in intestinal homeostasis. Several studies have shown that TLR2 can modulate inflammatory responses in the gut. TLR2 signals enhance tight junction formation and fortify the epithelial barrier, and may play a crucial role in driving acute inflammatory responses towards intestinal bacterial pathogens. In addition, TLR2 agonists can have direct effects on both Th1 cells and Treg. To define the role of TLR2 in the induction and regulation of chronic intestinal inflammation we examined the effects of TLR2 deletion on several complementary models of inflammatory bowel disease. Our results show that TLR2 signals are not required for the induction of chronic intestinal inflammation by either innate or adaptive immune responses. We further show that TLR2(-/-) mice harbor normal numbers of Foxp3(+) Treg that are able to suppress intestinal inflammation as effectively as their WT counterparts. We also did not find any intrinsic role for TLR2 for pathogenic effector T-cell responses in the gut. Thus, in contrast to their role in acute intestinal inflammation and repair, TLR2 signals may have a limited impact on the induction and regulation of chronic intestinal inflammation. PMID:19950179

  3. Peptidergic Agonists of Activity-Dependent Neurotrophic Factor Protect Against Prenatal Alcohol-Induced Neural Tube Defects and Serotonin Neuron Loss

    PubMed Central

    Zhou, Feng C.; Fang, Yuan; Goodlett, Charles

    2009-01-01

    Introduction Prenatal alcohol exposure via maternal liquid diet consumption by C57BL/6 (B6) mice causes conspicuous midline neural tube deficit (dysraphia) and disruption of genesis and development of serotonin (5-HT) neurons in the raphe nuclei, together with brain growth retardation. The current study tested the hypothesis that concurrent treatment with either an activity-dependent neurotrophic factor (ADNF) agonist peptide [SALLRSIPA, (SAL)] or an activity-dependent neurotrophic protein (ADNP) agonist peptide [NAPVSIPQ, (NAP)] would protect against these alcohol-induced deficits in brain development. Methods Timed-pregnant B6 dams consumed alcohol from embryonic day 7 (E7, before the onset of neurulation) until E15. Fetuses were obtained on E15 and brain sections processed for 5-HT immunocytochemistry, for evaluation of morphologic development of the brainstem raphe and its 5-HT neurons. Additional groups were treated either with SAL or NAP daily from E7 to E15 to assess the potential protective effects of these peptides. Measures of incomplete occlusion of the ventral canal and the frequency and extent of the openings in the rhombencephalon were obtained to assess fetal dysraphia. Counts of 5-HT-immunostained neurons were also obtained in the rostral and caudal raphe. Results Prenatal alcohol exposure resulted in abnormal openings along the midline and delayed closure of ventral canal in the brainstem. This dysraphia was associated with reductions in the number of 5-HT neurons both in the rostral raphe nuclei (that gives rise to ascending 5-HT projections) and in the caudal raphe (that gives rise to the descending 5-HT projections). Concurrent treatment of the alcohol-consuming dams with SAL prevented dysraphia and protected against the alcohol-induced reductions in 5-HT neurons in both the rostral and caudal raphe. NAP was less effective in protecting against dysraphia and did not protect against 5-HT loss in the rostral raphe, but did protect against loss in

  4. [The biliary intestinal obstruction].

    PubMed

    Demetrashvili, Z M; Asatiani, G A; Nemsadze, G Sh; Kenchadze, G Z

    2012-01-01

    The successful experience of treatment of 3 patients with biliary intestinal obstruction is depicted. The most informative means of diagnostics was the multispiral computed tomography. Authors state, that the volume of the operation should include only the liquidation of the intestinal obstruction. The simultaneous biliodigestive fistulae closure should be performed only in rare situations. PMID:22678540

  5. Gene expression profiles in the intestine of lipopolysaccharide-challenged piglets.

    PubMed

    Yi, Dan; Hou, Yongqing; Wang, Lei; Zhao, Di; Ding, Binying; Wu, Tao; Chen, Hongbo; Liu, Yulan; Kang, Ping; Wu, Guoyao

    2016-01-01

    Bowel diseases are common in human and animals and are characterized by intestinal dysfunction and injury. A well-established porcine model of intestinal injury can be induced by lipopolysaccharide (LPS), an endotoxin released from the cell wall of pathogenic bacteria. LPS affects the expression of genes associated with intestinal immune response, mucosal growth, energy metabolism, absorption, mucosal barrier function, and antiviral function. Transcriptional analysis of intestinal genes reveals that the duodenum, jejunum, ileum and colon respond to LPS challenge in a similar pattern. Moreover, the jejunum and ileum exhibit greater responses to LPS challenge than the duodenum and colon with regard to gene expression. Additionally, over 85% of genes are co-expressed along the small and large intestines and there is a clear distinction in gene expression patterns amongst the different intestinal segments in pigs. These findings have important implications for underlying molecular mechanisms responsible for endotoxin-induced intestinal injury and dysfunction. PMID:26709789

  6. Vagal nerve stimulation protects against burn-induced intestinal injury through activation of enteric glia cells.

    PubMed

    Costantini, Todd W; Bansal, Vishal; Krzyzaniak, Michael; Putnam, James G; Peterson, Carrie Y; Loomis, William H; Wolf, Paul; Baird, Andrew; Eliceiri, Brian P; Coimbra, Raul

    2010-12-01

    The enteric nervous system may have an important role in modulating gastrointestinal barrier response to disease through activation of enteric glia cells. In vitro studies have shown that enteric glia activation improves intestinal epithelial barrier function by altering the expression of tight junction proteins. We hypothesized that severe injury would increase expression of glial fibrillary acidic protein (GFAP), a marker of enteric glial activation. We also sought to define the effects of vagal nerve stimulation on enteric glia activation and intestinal barrier function using a model of systemic injury and local gut mucosal involvement. Mice with 30% total body surface area steam burn were used as model of severe injury. Vagal nerve stimulation was performed to assess the role of parasympathetic signaling on enteric glia activation. In vivo intestinal permeability was measured to assess barrier function. Intestine was collected to investigate changes in histology; GFAP expression was assessed by quantitative PCR, by confocal microscopy, and in GFAP-luciferase transgenic mice. Stimulation of the vagus nerve prevented injury-induced intestinal barrier injury. Intestinal GFAP expression increased at early time points following burn and returned to baseline by 24 h after injury. Vagal nerve stimulation prior to injury increased GFAP expression to a greater degree than burn alone. Gastrointestinal bioluminescence was imaged in GFAP-luciferase transgenic animals following either severe burn or vagal stimulation and confirmed the increased expression of intestinal GFAP. Injection of S-nitrosoglutathione, a signaling molecule released by activated enteric glia cells, following burn exerts protective effects similar to vagal nerve stimulation. Intestinal expression of GFAP increases following severe burn injury. Stimulation of the vagus nerve increases enteric glia activation, which is associated with improved intestinal barrier function. The vagus nerve may mediate the

  7. Modulation of Intestinal Epithelial Defense Responses by Probiotic Bacteria.

    PubMed

    Wan, L Y M; Chen, Z J; Shah, N P; El-Nezami, H

    2016-12-01

    Probiotics are live microorganisms, which when administered in food confer numerous health benefits. In previous studies about beneficial effects of probiotic bacteria to health, particularly in the fields of intestinal mucosa defense responses, specific probiotics, in a strain-dependent manner, show certain degree of potential to reinforce the integrity of intestinal epithelium and/or regulate some immune components. The mechanism of probiotic action is an area of interest. Among all possible routes of modulation by probiotics of intestinal epithelial cell-mediated defense responses, modulations of intestinal barrier function, innate, and adaptive mucosal immune responses, as well as signaling pathways are considered to play important role in the intestinal defense responses against pathogenic bacteria. This review summarizes the beneficial effects of probiotic bacteria to intestinal health together with the mechanisms affected by probiotic bacteria: barrier function, innate, and adaptive defense responses such as secretion of mucins, defensins, trefoil factors, immunoglobulin A (IgA), Toll-like receptors (TLRs), cytokines, gut associated lymphoid tissues, and signaling pathways. PMID:25629818

  8. [Establishment of the intestinal microflora in neonates].

    PubMed

    Campeotto, Florence; Waligora-Dupriet, Anne-Judith; Doucet-Populaire, Florence; Kalach, Nicolas; Dupont, Christophe; Butel, Marie-José

    2007-05-01

    The intestinal microbiota is a complex ecosystem harbouring about 10(14) micro-organisms composed of nearly 400 hundred species. It plays various important functions in the gut, including metabolic, flora, barrier and stimulation of the intestinal immune system. Most studies have been based on culture, but more recent molecular biology techniques have provided complementary information. The formation of this ecosystem begins rapidly in the newborn; it is sterile at birth and is based on contact with the maternal flora and the surrounding environment. Although little is known about the factors leading to the development of bacteria, numerous external factors will affect the microbial succession: mode of delivery, environmental conditions, type of feeding, gestational age, and antibiotics. Recent data report a delay in intestinal colonization especially of enteric maternal bacteria. Which may be due to strict hygiene measures during birth. The clinical impact of these variations is not known but they could lead to lack of barrier flora or poor immune system stimulation in the gut. Modulation of gut microbiota in neonates with infant formulas containing either probiotics, prebiotics or non viable bacterias and their metabolites, or nucleotides is discussed. PMID:17541346

  9. Gastroprotective activity of Nigella sativa L oil and its constituent, thymoquinone against acute alcohol-induced gastric mucosal injury in rats

    PubMed Central

    Kanter, Mehmet; Demir, Halit; Karakaya, Cengiz; Ozbek, Hanefi

    2005-01-01

    AIM: To evaluate the role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effect of Nigella sativa L oil (NS) and its constituent thymoquinone (TQ) in an exper-imental model. METHODS: Male Wistar albino rats were assigned into 4 groups. Control group was given physiologic saline orally (10 mL/kg body weight) as the vehicle (gavage); ethanol group was administrated 1 mL (per rat) absolute alcohol by gavage; the third and fourth groups were given NS (10 mL/kg body weight) and TQ (10 mg/kg body weight p.o) respectively 1 h prior to alcohol intake. One hour after ethanol administration, stomach tissues were excised for macroscopic examination and biochemical analysis. RESULTS: NS and TQ could protect gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. NS prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. NS also increased gastric glutathione content (GSH), enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, TQ protected against the ulcerating effect of alcohol and mitigated most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than NS. Neither NS nor TQ affected catalase activity in gastric tissue. CONCLUSION: Both NS and TQ, particularly NS can partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects might be induced, at least partly by their radical scavenging activity. PMID:16425361

  10. Voluntary exercise partially reverses neonatal alcohol-induced deficits in mPFC layer II/III dendritic morphology of male adolescent rats.

    PubMed

    Hamilton, G F; Criss, K J; Klintsova, A Y

    2015-08-01

    Developmental alcohol exposure in humans can produce a wide range of deficits collectively referred to as fetal alcohol spectrum disorders (FASD). FASD-related impairments in executive functioning later in life suggest long-term damage to the prefrontal cortex (PFC). In rodent neonates, moderate to high levels of alcohol exposure decreased frontal lobe brain size and altered medial PFC pyramidal neuron dendritic morphology. Previous research in our lab demonstrated that neonatal alcohol exposure decreased basilar dendritic complexity but did not affect spine density in Layer II/III pyramidal neurons in 26- to 30-day-old rats. The current study adds to the literature by evaluating the effect of neonatal alcohol exposure on mPFC Layer II/III basilar dendritic morphology in adolescent male rats. Additionally, it examines the potential for voluntary exercise to mitigate alcohol-induced deficits on mPFC dendritic complexity. An animal model of binge drinking during the third trimester of pregnancy was used. Rats were intubated with alcohol (alcohol-exposed, AE; 5.25 g kg(-1) day(-1)) on postnatal days (PD) 4-9; two control groups were included (suckle control and sham-intubated). Rats were anesthetized and perfused with heparinized saline solution on PD 42, and brains were processed for Golgi-Cox staining. Developmental alcohol exposure decreased spine density and dendritic complexity of basilar dendrites of Layer II/III neurons in the medial PFC (mPFC) compared to dendrites of control animals. Voluntary exercise increased spine density and dendritic length in AE animals resulting in elimination of the differences between AE and SH rats. Thus, voluntary exercise during early adolescence selectively rescued alcohol-induced morphological deficits in the mPFC. PMID:25967699

  11. Strong Protective Effect of The Aldehyde Dehydrogenase Gene (ALDH2) 504lys (*2) Allele Against Alcoholism And Alcohol-Induced Medical Diseases in Asians

    PubMed Central

    Li, Dawei; Zhao, Hongyu; Gelernter, Joel

    2013-01-01

    Alcohol is oxidized to acetaldehyde, which in turn is oxidized to acetate. The aldehyde dehydrogenase 2 gene (ALDH2) is the most important gene responsible for acetaldehyde metabolism. Individuals heterozygous or homozygous for the lys (A or *2) allele at the single nucleotide polymorphism (SNP) glu504lys (rs671) of ALDH2 have greatly reduced ability to metabolize acetaldehyde, which greatly decreases their risk for alcohol dependence (AD). Case-control studies have shown association between this SNP and alcohol dependence as well as alcohol-induced liver disease. However, some studies have produced insignificant results. Using cumulative data from the past 20 years predominately from Asian populations (from both English and Chinese publications), this meta-analysis sought to examine and update whether the aggregate data provide new evidence of statistical significance for the proposed association. Our results (9,678 cases and 7,331 controls from 53 studies) support a strong association of alcohol abuse and dependence, with allelic P value of 3×10−56 and OR of 0.23 (0.2, 0.28) under the random effects model. The dominant model (lys-lys + lys-glu vs. glu-glu) also showed strong association with P value of 1×10−44 and OR of 0.22 (0.18, 0.27). When stricter criteria and various sub-group analyses were applied, the association remained strong (for example, OR = 0.23 (0.18, 0.3) and P = 2×10−28 for the alcoholic patients with alcoholic liver disease, cirrhosis, or pancreatitis). These findings provide confirmation of the involvement of the human ALDH2 gene in the pathogenesis of AD as well as alcohol-induced medical illnesses in East-Asians. PMID:22102315

  12. The Ayurvedic drug Ksheerabala (101) ameliorates alcohol-induced neurotoxicity by down-regulating the expression of transcription factor (NFkB) in rat brain

    PubMed Central

    Rejitha, S.; Prathibha, P.; Madambath, Indira

    2015-01-01

    Introduction: Most of the pharmaceutical effects of alcohol are due to its accumulation in the brain. Ksheerabala (101) an Ayurvedic formulation mainly used against central nervous system disorders. Aim: To determine the antioxidant and neuroprotective effect of Ksheerabala (101) on alcohol-induced oxidative stress in rats. Materials and Methods: Male Albino rats of Sprague-Dawley strain were grouped into four; control, alcohol (4 g/kg), Ksheerabala (15 μL/1 ml milk/100 g) and Ksheerabala (15 μL/1 ml milk/100 g) + alcohol (4 g/kg). After the experimental period (90 days), the animals were sacrificed and the effect of Ksheerabala (101) was studied on oxidative stress, inflammatory markers, and induction of transcription factor in brain. Results were statistically analyzed by one-way ANOVA. Results: The activities of antioxidant enzymes and reduced glutathione which were decreased in alcohol-treated rats, increased significantly in co-administered groups. The lipid peroxidation products and protein carbonyls which were increased significantly in alcohol-treated rats decreased significantly in co-administered groups. The expression of gamma-glutamyl cysteine synthase decreased significantly in alcohol-treated rats and increased significantly in co-administered groups. The transcription factor nuclear factor-κB (NFκB) which was up-regulated in alcohol-treated rats was down-regulated in co-administered rats. The histopathology reinforced these results. Conclusion: Ksheerabala (101) attenuates alcohol-induced oxidative stress and down-regulates the expression of NFκB in rat brain. PMID:27313421

  13. Increased hepatic receptor interacting protein kinase 3 expression due to impaired proteasomal functions contributes to alcohol-induced steatosis and liver injury

    PubMed Central

    Wang, Shaogui; Ni, Hong-Min; Dorko, Kenneth; Kumer, Sean C.; Schmitt, Timothy M.; Nawabi, Atta; Komatsu, Masaaki; Huang, Heqing; Ding, Wen-Xing

    2016-01-01

    Chronic alcohol exposure increased hepatic receptor-interacting protein kinase (RIP) 3 expression and necroptosis in the liver but its mechanisms are unclear. In the present study, we demonstrated that chronic alcohol feeding plus binge (Gao-binge) increased RIP3 but not RIP1 protein levels in mouse livers. RIP3 knockout mice had decreased serum alanine amino transferase activity and hepatic steatosis but had no effect on hepatic neutrophil infiltration compared with wild type mice after Gao-binge alcohol treatment. The hepatic mRNA levels of RIP3 did not change between Gao-binge and control mice, suggesting that alcohol-induced hepatic RIP3 proteins are regulated at the posttranslational level. We found that Gao-binge treatment decreased the levels of proteasome subunit alpha type-2 (PSMA2) and proteasome 26S subunit, ATPase 1 (PSMC1) and impaired hepatic proteasome function. Pharmacological or genetic inhibition of proteasome resulted in the accumulation of RIP3 in mouse livers. More importantly, human alcoholics had decreased expression of PSMA2 and PSMC1 but increased protein levels of RIP3 compared with healthy human livers. Moreover, pharmacological inhibition of RIP1 decreased Gao-binge-induced hepatic inflammation, neutrophil infiltration and NF-κB subunit (p65) nuclear translocation but failed to protect against steatosis and liver injury induced by Gao-binge alcohol. In conclusion, results from this study suggest that impaired hepatic proteasome function by alcohol exposure may contribute to hepatic accumulation of RIP3 resulting in necroptosis and steatosis while RIP1 kinase activity is important for alcohol-induced inflammation. PMID:26769846

  14. Intestinal adaptation after massive intestinal resection

    PubMed Central

    Weale, A; Edwards, A; Bailey, M; Lear, P

    2005-01-01

    Patients with short bowel syndrome require long term parenteral nutrition support. However, after massive intestinal resection the intestine undergoes adaptation and nutritional autonomy may be obtained. Given that the complications of parenteral nutrition may be life threatening or result in treatment failure and the need for intestinal transplantation, a more attractive option is to wean patients off nutrition support by optimising the adaptive process. The article examines the evidence that after extensive small bowel resection adaptation occurs in humans and focuses on the factors that influence adaptation and the strategies that have been used to optimise this process. The review is based on an English language Medline search with secondary references obtained from key articles. There is evidence that adaptation occurs in humans. Adaptation is a complex process that results in response to nutrient and non-nutrient stimuli. Successful and reproducible strategies to improve adaptation remain elusive despite an abundance of experimental data. Nevertheless given the low patient survival and quality of life associated with other treatments for irreversible intestinal failure it is imperative that clinical research continues into the optimisation of the adaptation. PMID:15749794

  15. Language barriers

    PubMed Central

    Ngwakongnwi, Emmanuel; Hemmelgarn, Brenda R.; Musto, Richard; King-Shier, Kathryn M.; Quan, Hude

    2012-01-01

    Abstract Objective To assess use of regular medical doctors (RMDs), as well as awareness and use of telephone health lines or telehealth services, by official language minorities (OLMs) in Canada. Design Analysis of data from the 2006 postcensal survey on the vitality of OLMs. Setting Canada. Participants In total, 7691 English speakers in Quebec and 12 376 French speakers outside Quebec, grouped into those who experienced language barriers and those with no language barriers. Main outcome measures Health services utilization (HSU) by the presence of language barriers; HSU measures included having an RMD, use of an RMD’s services, and awareness of and use of telephone health lines or telehealth services. Multivariable models examined the associations between HSU and language barriers. Results After adjusting for age and sex, English speakers residing in Quebec with limited proficiency in French were less likely to have RMDs (adjusted odds ratio [AOR] 0.66, 95% CI 0.50 to 0.87) and to use the services of their RMDs (AOR 0.65, 95% CI 0.50 to 0.86), but were more likely to be aware of the existence of (AOR 1.50, 95% CI 1.16 to 1.93) and to use (AOR 1.43, 95% CI 0.97 to 2.11) telephone health lines or telehealth services. This pattern of having and using RMDs and telehealth services was not observed for French speakers residing outside of Quebec. Conclusion Overall we found variation in HSU among the language barrier populations, with lower use observed in Quebec. Age older than 45 years, male sex, being married or in common-law relationships, and higher income were associated with having RMDs for OLMs. PMID:23242902

  16. Distraction-induced intestinal enterogenesis: Preservation of intestinal function and lengthening after re-implantation into normal jejunum

    PubMed Central

    Koga, Hiroyuki; Sun, Xiaoyi; Yang, Hua; Nose, Keisuke; Somara, Sita; Bitar, Khalil N; Owyang, Chung; Okawada, Manabu; Teitelbaum, Daniel H

    2011-01-01

    Background Significant bowel lengthening can occur in an isolated intestinal segment with the use for linearly directed distractive forces; resulting in increased surface area and epithelial cell proliferation. We hypothesized that re-implantation of this lengthened intestine into normal jejunum would preserve this gain in intestinal length and function similar to normal jejunum. Methods An intestinal lengthening device was inserted into isolated jejunal segments in pigs, and fully expanded over 8 days. Lengthened segment were then re-implanted into normal intestinal continuity. Pigs were studied after another 28days. Function was assessed by motility, mucosal enzyme activity, barrier function and intestinal ion transport. Results Lengthened segments were significantly longer than control segments, and had nearly 2-fold greater surface area. Bowel lengthening was maintained 4 weeks after re-implantation. Motility after re-implantation was similar to non-operated pigs. Barrier function, mucosal disaccharidase levels and electrophysiologic measures declined immediately after lengthening, but returned to nearly normal levels 28 days after re-implantation. Conclusion Bowel lengthening results in a transient decline in mucosal absorptive function and smooth muscle contractility. However, function approaches that of normal bowel after re-implantation into enteric flow. These data may support the use of this technique as a potential new option for the treatment of patients with short bowel syndrome. PMID:21997804

  17. Intestinal colonization resistance

    PubMed Central

    Lawley, Trevor D; Walker, Alan W

    2013-01-01

    Dense, complex microbial communities, collectively termed the microbiota, occupy a diverse array of niches along the length of the mammalian intestinal tract. During health and in the absence of antibiotic exposure the microbiota can effectively inhibit colonization and overgrowth by invading microbes such as pathogens. This phenomenon is called ‘colonization resistance’ and is associated with a stable and diverse microbiota in tandem with a controlled lack of inflammation, and involves specific interactions between the mucosal immune system and the microbiota. Here we overview the microbial ecology of the healthy mammalian intestinal tract and highlight the microbe–microbe and microbe–host interactions that promote colonization resistance. Emerging themes highlight immunological (T helper type 17/regulatory T-cell balance), microbiota (diverse and abundant) and metabolic (short-chain fatty acid) signatures of intestinal health and colonization resistance. Intestinal pathogens use specific virulence factors or exploit antibiotic use to subvert colonization resistance for their own benefit by triggering inflammation to disrupt the harmony of the intestinal ecosystem. A holistic view that incorporates immunological and microbiological facets of the intestinal ecosystem should facilitate the development of immunomodulatory and microbe-modulatory therapies that promote intestinal homeostasis and colonization resistance. PMID:23240815

  18. Mucin Dynamics in Intestinal Bacterial Infection

    PubMed Central

    Lindén, Sara K.; Florin, Timothy H. J.; McGuckin, Michael A.

    2008-01-01

    Background Bacterial gastroenteritis causes morbidity and mortality in humans worldwide. Murine Citrobacter rodentium infection is a model for gastroenteritis caused by the human pathogens enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. Mucin glycoproteins are the main component of the first barrier that bacteria encounter in the intestinal tract. Methodology/Principal Findings Using Immunohistochemistry, we investigated intestinal expression of mucins (Alcian blue/PAS, Muc1, Muc2, Muc4, Muc5AC, Muc13 and Muc3/17) in healthy and C. rodentium infected mice. The majority of the C. rodentium infected mice developed systemic infection and colitis in the mid and distal colon by day 12. C. rodentium bound to the major secreted mucin, Muc2, in vitro, and high numbers of bacteria were found in secreted MUC2 in infected animals in vivo, indicating that mucins may limit bacterial access to the epithelial surface. In the small intestine, caecum and proximal colon, the mucin expression was similar in infected and non-infected animals. In the distal colonic epithelium, all secreted and cell surface mucins decreased with the exception of the Muc1 cell surface mucin which increased after infection (p<0.05). Similarly, during human infection Salmonella St Paul, Campylobacter jejuni and Clostridium difficile induced MUC1 in the colon. Conclusion Major changes in both the cell-surface and secreted mucins occur in response to intestinal infection. PMID:19088856

  19. Gastrointestinal gene delivery by cyclodextrins--in vitro quantification of extracellular barriers.

    PubMed

    O'Neill, Martin J; O'Mahony, Aoife M; Byrne, Colin; Darcy, Raphael; O'Driscoll, Caitriona M

    2013-11-18

    Local gene delivery represents a promising therapeutic approach for diseases of the intestine. However, the gastrointestinal tract poses significant challenges to successful gene delivery. Cyclodextrins (CDs) have been extensively investigated as non-viral vectors. Here, we assessed the suitability of an amphiphilic cationic CD for intestinal gene transfer, with particular focus on extracellular barriers. Stability and transfection efficiency of CD·DNA complexes were assessed post incubation in simulated gastric and intestinal fluids, bile salts and mucin, or with intestinal enzymes to represent extracellular barriers to intestinal gene delivery. Stability was determined by gel electrophoresis and transfection was measured by luciferase expression in intestinal epithelial cells (Caco-2). Transfection efficiency of CD·DNA complexes was enhanced after incubation in bile salts but was reduced after incubation in gastric and intestinal fluids and mucin. CD·DNA complexes were stable after incubation with pancreatic enzymes and with a model lower intestinal enzyme. Furthermore, the CD protected pDNA from degradation by DNase. In summary, physiologically relevant in vitro models were established and used to quantify the barriers posed by the intestinal extracellular environment to gene delivery. This systematic assessment identified the advantages and limitations of the CD vector and facilitated the proposal of formulation strategies to overcome these barriers. PMID:24016741

  20. Pediatric intestinal motility disorders

    PubMed Central

    Gfroerer, Stefan; Rolle, Udo

    2015-01-01

    Pediatric intestinal motility disorders affect many children and thus not only impose a significant impact on pediatric health care in general but also on the quality of life of the affected patient. Furthermore, some of these conditions might also have implications for adulthood. Pediatric intestinal motility disorders frequently present as chronic constipation in toddler age children. Most of these conditions are functional, meaning that constipation does not have an organic etiology, but in 5% of the cases, an underlying, clearly organic disorder can be identified. Patients with organic causes for intestinal motility disorders usually present in early infancy or even right after birth. The most striking clinical feature of children with severe intestinal motility disorders is the delayed passage of meconium in the newborn period. This sign is highly indicative of the presence of Hirschsprung disease (HD), which is the most frequent congenital disorder of intestinal motility. HD is a rare but important congenital disease and the most significant entity of pediatric intestinal motility disorders. The etiology and pathogenesis of HD have been extensively studied over the last several decades. A defect in neural crest derived cell migration has been proven as an underlying cause of HD, leading to an aganglionic distal end of the gut. Numerous basic science and clinical research related studies have been conducted to better diagnose and treat HD. Resection of the aganglionic bowel remains the gold standard for treatment of HD. Most recent studies show, at least experimentally, the possibility of a stem cell based therapy for HD. This editorial also includes rare causes of pediatric intestinal motility disorders such as hypoganglionosis, dysganglionosis, chronic intestinal pseudo-obstruction and ganglioneuromatosis in multiple endocrine metaplasia. Underlying organic pathologies are rare in pediatric intestinal motility disorders but must be recognized as early as

  1. Pediatric intestinal motility disorders.

    PubMed

    Gfroerer, Stefan; Rolle, Udo

    2015-09-01

    Pediatric intestinal motility disorders affect many children and thus not only impose a significant impact on pediatric health care in general but also on the quality of life of the affected patient. Furthermore, some of these conditions might also have implications for adulthood. Pediatric intestinal motility disorders frequently present as chronic constipation in toddler age children. Most of these conditions are functional, meaning that constipation does not have an organic etiology, but in 5% of the cases, an underlying, clearly organic disorder can be identified. Patients with organic causes for intestinal motility disorders usually present in early infancy or even right after birth. The most striking clinical feature of children with severe intestinal motility disorders is the delayed passage of meconium in the newborn period. This sign is highly indicative of the presence of Hirschsprung disease (HD), which is the most frequent congenital disorder of intestinal motility. HD is a rare but important congenital disease and the most significant entity of pediatric intestinal motility disorders. The etiology and pathogenesis of HD have been extensively studied over the last several decades. A defect in neural crest derived cell migration has been proven as an underlying cause of HD, leading to an aganglionic distal end of the gut. Numerous basic science and clinical research related studies have been conducted to better diagnose and treat HD. Resection of the aganglionic bowel remains the gold standard for treatment of HD. Most recent studies show, at least experimentally, the possibility of a stem cell based therapy for HD. This editorial also includes rare causes of pediatric intestinal motility disorders such as hypoganglionosis, dysganglionosis, chronic intestinal pseudo-obstruction and ganglioneuromatosis in multiple endocrine metaplasia. Underlying organic pathologies are rare in pediatric intestinal motility disorders but must be recognized as early as

  2. Understanding epithelial homeostasis in the intestine

    PubMed Central

    De Mey, Jan R.; Freund, Jean-Noël

    2013-01-01

    The intestinal epithelium constitutes the barrier between the gut lumen and the rest of the body and a very actively renewing cell population. The crypt/villus and crypt/cuff units of the mouse small intestine and colon are its basic functional units. The field is confronted with competing concepts with regard to the nature of the cells that are responsible for all the day-to day cell replacement and those that act to regenerate the tissue upon injury and with two diametrically opposed models for lineage specification. The review revisits groundbreaking pioneering studies to provide non expert readers and crypt watchers with a factual analysis of the origins of the current models deduced from the latest spectacular advances. It also discusses recent progress made by addressing these issues in the crypts of the colon, which need to be better understood, since they are the preferred sites of major pathologies. PMID:24665395

  3. Intestinal permeability and bacterial translocation following small bowel transplantation in the rat

    SciTech Connect

    Grant, D.; Hurlbut, D.; Zhong, R.; Wang, P.Z.; Chen, H.F.; Garcia, B.; Behme, R.; Stiller, C.; Duff, J. )

    1991-08-01

    In addition to its role in absorbing nutrients, the intestinal mucosa provides an important barrier against toxins and bacteria in the bowel lumen. The present study evaluated gut barrier function following orthotopic (in continuity) intestinal grafting in rats. Graft histology, intestinal permeability, and bacterial translocation to the grafted mesenteric lymph nodes, the host's liver, and the host's spleen were assessed on the 3rd, 5th, and 7th postoperative days. The study group received no immunosuppression after allotransplantation. The two control groups included rats with isografts and rats with cyclosporine-treated allografts. On the 7th POD, the study animals had moderate transmural inflammation due to rejection, with normal histology in the isografts and CsA-treated allografts; increased intestinal permeability, measured by urinary excretion of oral 51Cr-EDTA (P less than 0.01); and increased number of bacteria in the MLN and spleen (P less than 0.05). The number of bacteria in the MLN and spleen of the study group positively correlated with the changes in intestinal permeability (P less than 0.05). Rejection of the orthotopic intestinal graft leads to increased intestinal permeability and bacterial translocation from the lumen of the graft to the host's reticuloendothelial system. Measures to improve gut barrier function and antibiotic therapy during rejection episodes may help reduce the incidence of septic complications after intestinal grafting.

  4. Interleukin-22 Promotes Intestinal Stem Cell-Mediated Epithelial Regeneration

    PubMed Central

    Dudakov, Jarrod A.; Jenq, Robert R.; Velardi, Enrico; Young, Lauren F.; Smith, Odette M.; Lawrence, Gillian; Ivanov, Juliet A.; Fu, Ya-Yuan; Takashima, Shuichiro; Hua, Guoqiang; Martin, Maria L.; O'Rourke, Kevin P.; Lo, Yuan-Hung; Mokry, Michal; Romera-Hernandez, Monica; Cupedo, Tom; Dow, Lukas; Nieuwenhuis, Edward E.; Shroyer, Noah F.; Liu, Chen; Kolesnick, Richard

    2015-01-01

    Epithelial regeneration is critical for barrier maintenance and organ function after intestinal injury. The intestinal stem cell (ISC) niche provides Wnt, Notch, and epidermal growth factor (EGF) signals supporting Lgr5+ crypt base columnar ISCs for normal epithelial maintenance1,2. However, little is known about the r