scholarly journals Renin‐angiotensin system in intestinal inflammation – Angiotensin inhibitors to treat inflammatory bowel diseases?

Author(s):  
Hanne Salmenkari ◽  
Riitta Korpela ◽  
Heikki Vapaatalo
2015 ◽  
Vol 33 (Suppl. 1) ◽  
pp. 26-31
Author(s):  
Hans Herfarth ◽  
Andreas G. Schreyer

Diagnostic imaging techniques play an important role in the diagnosis and management of patients with inflammatory bowel diseases (IBDs). The approach should be guided by considerations of diagnostic accuracy, concerns about patient exposure to ionizing radiation, local expertise and tolerance of the endoscopic and/or imaging technique. In regard to the clinical diagnostic value (sensitivity, specificity and accuracy), no significant differences exist between CT and MRI for the evaluation of the extent of inflammation, stricturing, penetrating disease or extraluminal complications such as abscesses. Due to the absence of radiation exposure, MRI of the intestine is recommended as the first-line imaging modality in patients with suspected or established IBD. The focus of this review is the latest developments in MRI techniques to detect IBDs. Specifically, the use of new indices for the grading of inflammation or assessing bowel damage as well as innovative experimental approaches such as diffusion-weighted imaging or magnetization-transfer MRI to evaluate and quantify the degree of intestinal inflammation and fibrosis in stricturing Crohn's disease are discussed.


2021 ◽  
Author(s):  
Jiří Hrdý ◽  
Aurélie Couturier-Maillard ◽  
Denise Boutillier ◽  
Carmen Lapadatescu ◽  
Philippe Blanc ◽  
...  

Abstract Live biotherapeutic products constitute an emerging therapeutic approach to prevent or treat inflammatory bowel diseases. Lactobacillus acidophilus is a constituent of the human microbiota with probiotic potential, that are illustrated by direct and indirect antimicrobial activity against several pathogens and improvement of intestinal inflammation. In this study, we evaluated the anti-inflammatory properties of the L. acidophilus strain BIO5768 and assessed the underlying mechanisms of action. BIO5768 was able to counteract the acute colitis that is induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). When administered alone or in combination with Bifidobacterium animalis spp. lactis BIO5764 and Limosilactobacillus reuteri, BIO5768 was also able to alleviate intestinal inflammation induced by Citrobacter rodentium infection. Supplementation of naïve mice with either strain BIO5768 alone or as mixture, increased the gene expression of several target genes involved in immune signaling, including c-type lectin Reg3 gamma. Consistently, the ability of innate lymphoid cells to secrete IL-22 was enhanced in response to BIO5768. Interestingly, the aforementioned responses were shown to be independent of NOD2 and Th17 signaling in mice that were mono-colonized with BIO5768. In conclusion, we identify a new potential probiotic strain with the ability for the management of inflammatory bowel diseases, and provide some insights into its mode of action.


2020 ◽  
Vol 79 (4) ◽  
pp. 468-478 ◽  
Author(s):  
Stefania Del Fabbro ◽  
Philip C. Calder ◽  
Caroline E. Childs

The aim of the present paper is to review the effects of non-digestible oligosaccharides (NDO) on immunity, focusing on their microbiota-independent mechanisms of action, as well as to explore their potential beneficial role in inflammatory bowel diseases (IBD). IBD are chronic, inflammatory conditions of the gastrointestinal tract. Individuals with IBD have an aberrant immune response to commensal microbiota, resulting in extensive mucosal inflammation and increased intestinal permeability. NDO are prebiotic fibres well known for their role in supporting intestinal health through modulation of the gut microbiota. NDO reach the colon intact and are fermented by commensal bacteria, resulting in the production of SCFA with immunomodulatory properties. In disease states characterised by increased gut permeability, prebiotics may also bypass the gut barrier and directly interact with intestinal and systemic immune cells, as demonstrated in patients with IBD and in infants with an immature gut. In vitro models show that fructooligosaccharides, inulin and galactooligosaccharides exert microbiota-independent effects on immunity by binding to toll-like receptors on monocytes, macrophages and intestinal epithelial cells and by modulating cytokine production and immune cell maturation. Moreover, animal models and human supplementation studies demonstrate that some prebiotics, including inulin and lactulose, might reduce intestinal inflammation and IBD symptoms. Although there are convincing preliminary data to support NDO as immunomodulators in the management of IBD, their mechanisms of action are still unclear and larger standardised studies need to be performed using a wider range of prebiotics.


Gut ◽  
2019 ◽  
Vol 69 (5) ◽  
pp. 841-851 ◽  
Author(s):  
Mayur Garg ◽  
Simon G Royce ◽  
Chris Tikellis ◽  
Claire Shallue ◽  
Duygu Batu ◽  
...  

ObjectiveWe evaluated the influence of the renin–angiotensin system (RAS) on intestinal inflammation and fibrosis.DesignCultured human colonic myofibroblast proliferation and collagen secretion were assessed following treatment with angiotensin (Ang) II and Ang (1–7), their receptor antagonists candesartan and A779, and the ACE inhibitor captopril. Circulating and intestinal RAS components were evaluated in patients with and without IBD. Disease outcomes in patients with IBD treated with ACE inhibitors and angiotensin receptor blockers (ARBs) were assessed in retrospective studies.ResultsHuman colonic myofibroblast proliferation was reduced by Ang (1–7) in a dose-dependent manner (p<0.05). Ang II marginally but not significantly increased proliferation, an effect reversed by candesartan (p<0.001). Colonic myofibroblast collagen secretion was reduced by Ang (1–7) (p<0.05) and captopril (p<0.001), and was increased by Ang II (p<0.001). Patients with IBD had higher circulating renin (mean 25.4 vs 18.6 mIU/L, p=0.026) and ACE2:ACE ratio (mean 0.92 vs 0.69, p=0.015) than controls without IBD. RAS gene transcripts and peptides were identified in healthy and diseased bowels. Colonic mucosal Masson’s trichrome staining correlated with Ang II (r=0.346, p=0.010) and inversely with ACE2 activity (r=−0.373, p=0.006). Patients with IBD who required surgery (1/37 vs 12/75, p=0.034) and hospitalisation (0/34 vs 8/68, p=0.049) over 2 years were less often treated with ACE inhibitors and ARBs than patients not requiring surgery or hospitalisation.ConclusionsThe RAS mediates fibrosis in human cell cultures, is expressed in the intestine and perturbed in intestinal inflammation, and agents targeting this system are associated with improved disease outcomes.


2011 ◽  
Vol 11 ◽  
pp. 1536-1547 ◽  
Author(s):  
Donata Lissner ◽  
Britta Siegmund

Inflammasomes are intracellular multiprotein complexes that coordinate the maturation of interleukin (IL)-1β and IL-18 in response to pathogens and metabolic danger. Both cytokines have been linked to intestinal inflammation. However, recently evolving concepts ascribe a major role to the inflammasome in maintaining intestinal homeostasis. This review recapitulates its position in the development of inflammatory bowel disease, thereby outlining a model in which hypo- as well as hyperfunctionality can lead to an imbalance of the system, depending on the specific cell population affected. In the epithelium, the inflammasome is essential for regulation of permeability and epithelial regeneration through sensing of commensal microbes, while excessive inflammasome activation within the lamina propria contributes to severe intestinal inflammation.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Tiago Nunes ◽  
Claudio Bernardazzi ◽  
Heitor S. de Souza

Interleukin- (IL-) 33 is a widely expressed cytokine present in different cell types, such as epithelial, mesenchymal, and inflammatory cells, supporting a predominant role in innate immunity. IL-33 can function as a proinflammatory cytokine inducing Th2 type of immune response being involved with the defense against parasitic infections of the gastrointestinal tract. In addition, it has been proposed that IL-33 can act as a signaling molecule alerting the immune system of danger or tissue damage. Recently, in the intestinal mucosa, overexpression of IL-33 has been reported in samples from patients with inflammatory bowel diseases (IBD). This review highlights the available data regarding IL-33 in human IBD and discusses emerging roles for IL-33 as a key modulator of intestinal inflammation.


2021 ◽  
Vol 11 (1) ◽  
pp. 80-87
Author(s):  
Nadja Maria da Costa Melo ◽  
Marília Virgo Silva Almeida ◽  
Daniel Melo de Oliveira Campos ◽  
Claudio Bruno Silva de Oliveira ◽  
Jonas Ivan Nobre Oliveira

Objective: To identify and describe comparatively the chemical models of the induction of inflammatory bowel diseases (IBD) in rodents most used and that best mimic the pathogenesis in humans. Methods: Based on an integrative review in the MEDLINE and LILACS databases, it was investigated which experimental induction models were most cited in articles published from 2004 to 2020, with the descriptors "Colitis/CI", "Colitis model ulcerative" and "Intestinal inflammation model." All empirical articles that addressed one or more inflammation models in rats or mice were included. Results: 239 articles were identified; of these, only ten empirical articles were selected. The most used models were colitis induced by TNBS acid, DSS, and colitis induced by acetic acid (AA). Conclusion: It was possible to identify the most used models to promote the induction of intestinal inflammation in rats, and both models proved to be effective according to the limitations observed in the models described, suggesting the need for new works that use more well-defined protocols and that more fully represent the pathophysiological complexity of the disease.


2021 ◽  
Vol 18 (1) ◽  
pp. 20-29
Author(s):  
S. A. Bulgakov ◽  
G. M. Chernakova ◽  
E. A. Kleshcheva ◽  
S. V. Simonova

Crohn’s disease and ulcerative colitis are chronic inflammatory bowel diseases, which are often accompanied by inflammation of other organs. This article presents modern data on etiology, pathogenesis and clinical course of inflammatory bowel diseases, as well as information on extraintestinal eye manifestations of nonspecific ulcerative colitis and Crohn’s disease. The role of microbiota, genetic factors, immune system defects in pathogenesis of intestinal inflammation and extraintestinal eye manifestations is considered. The possibility the development of ophthalmopathology not only against the background of intestinal inflammation, but also as a consequence of therapeutic and surgical methods of treatment of ulcerative colitis and Crohn’s disease is noted. The peculiarities of the course of episcleritis/scleritis, keratitis, uveitis, chorioretinitis, optical neuritis for patients with inflammatory bowel diseases are considered. The presence of these complications may reflect the activity of the underlying disease, which in some cases requires correction of therapy. Anterior uveitis and episcleritis/scleritis are the most common extraintestinal manifestations of inflammatory bowel disease. Inflammation of tissues of the posterior segment of the eye and optic nerve against the background of ulcerative colitis and Crohn’s disease are less common, but are of clinical importance, as they can catastrophically damage the structures of the eye and, as a consequence, lead to complete blindness. Considering the possibility of mild clinical symptoms and asymptomatic course of inflammation in the eye envelopes, the importance of ophthalmological examination of all patients with ulcerative colitis and Crohn’s disease is emphasized. Aspects of modern therapy of ophthalmopathology and background intestinal inflammation are highlighted. Biological preparations — antagonists of pro-inflammatory cytokines — have been identified as the most promising in the treatment of inflammatory intestinal diseases and extraintestinal manifestations. The important role of proper nutrition and biologically active supplements containing omega-3 fatty acids, vitamin D, microelements, was noted as auxiliary therapy of both intestinal and extraintestinal inflammation.


Sign in / Sign up

Export Citation Format

Share Document