scholarly journals An innately dangerous balancing act: intestinal homeostasis, inflammation, and colitis-associated cancer

2010 ◽  
Vol 207 (8) ◽  
pp. 1573-1577 ◽  
Author(s):  
Mark Asquith ◽  
Fiona Powrie
Keyword(s):  
Intestinal Inflammation ◽  
Innate Immune ◽  
Intestinal Epithelial ◽  
Intestinal Homeostasis ◽  
Functional Roles ◽  
Innate Immune Signaling ◽  
Distinct Disease ◽  
Inflammatory Bowel ◽  
Immune Sensing ◽  
Chronic Intestinal Inflammation

Inflammatory bowel disease (IBD) is characterized by dysregulated immune responses to the intestinal microbiota, and by chronic intestinal inflammation. Several recent studies demonstrate the importance of innate microbial recognition by immune and nonimmune cells in the gut. Paradoxically, either diminished or exacerbated innate immune signaling may trigger the breakdown of intestinal homeostasis, leading to IBD and colitis-associated cancer (CAC). This dichotomy may reflect divergent functional roles for immune sensing in intestinal epithelial cells and leukocytes, which may vary with distinct disease mechanisms.

scholarly journals H89 Treatment Reduces Intestinal Inflammation and Candida albicans Overgrowth in Mice

2020 ◽  
Vol 8 (12) ◽  
pp. 2039
Author(s):  
Corentin Dumortier ◽  
Rogatien Charlet ◽  
Ali Bettaieb ◽  
Samir Jawhara
Keyword(s):  
Candida Albicans ◽  
Gut Microbiota ◽  
Intestinal Inflammation ◽  
Innate Immune ◽  
Intestinal Epithelial ◽  
Opportunistic Pathogens ◽  
Inflammatory Bowel ◽  
The Impact ◽  
Migration Of Macrophages ◽  
Pro Inflammatory Cytokines

Deregulation of the dynamic crosstalk between the gut microbiota, intestinal epithelial cells, and immune cells is critically involved in the development of inflammatory bowel disease and the overgrowth of opportunistic pathogens, including the human opportunistic fungus Candida albicans. In the present study, we assessed the effect of N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H89), a protein kinase A inhibitor, on the migration of macrophages to C. albicans through dextran sulphate sodium (DSS)-challenged Caco-2 cells. We also investigated the impact of H89 on intestinal inflammation and C. albicans clearance from the gut, and determined the diversity of the gut microbiota in a murine model of DSS-induced colitis. H89 reduced the migration of macrophages to C. albicans through DSS-challenged Caco-2 cells. In addition, H89 decreased C. albicans viability and diminished the expression of pro-inflammatory cytokines and innate immune receptors in macrophages and colonic epithelial Caco-2 cells. In mice with DSS-induced colitis, H89 attenuated the clinical and histological scores of inflammation and promoted the elimination of C. albicans from the gut. H89 administration to mice decreased the overgrowth of Escherichia coli and Enterococcus faecalis populations while Lactobacillus johnsonii populations increased significantly. Overall, H89 reduced intestinal inflammation and promoted the elimination of C. albicans from the gut.

scholarly journals Innate Lymphoid Cells in Intestinal Homeostasis and Inflammatory Bowel Disease

2021 ◽  
Vol 22 (14) ◽  
pp. 7618
Author(s):  
Angela Saez ◽  
Raquel Gomez-Bris ◽  
Beatriz Herrero-Fernandez ◽  
Claudia Mingorance ◽  
Cristina Rius ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
T Cells ◽  
Bowel Disease ◽  
Intestinal Inflammation ◽  
Innate Lymphoid Cells ◽  
Lymphoid Cells ◽  
Intestinal Homeostasis ◽  
Mucosal Homeostasis ◽  
Inflammatory Bowel ◽  
Chronic Intestinal Inflammation

Inflammatory bowel disease (IBD) is a heterogeneous state of chronic intestinal inflammation of unknown cause encompassing Crohn’s disease (CD) and ulcerative colitis (UC). IBD has been linked to genetic and environmental factors, microbiota dysbiosis, exacerbated innate and adaptive immunity and epithelial intestinal barrier dysfunction. IBD is classically associated with gut accumulation of proinflammatory Th1 and Th17 cells accompanied by insufficient Treg numbers and Tr1 immune suppression. Inflammatory T cells guide innate cells to perpetuate a constant hypersensitivity to microbial antigens, tissue injury and chronic intestinal inflammation. Recent studies of intestinal mucosal homeostasis and IBD suggest involvement of innate lymphoid cells (ILCs). These lymphoid-origin cells are innate counterparts of T cells but lack the antigen receptors expressed on B and T cells. ILCs play important roles in the first line of antimicrobial defense and contribute to organ development, tissue protection and regeneration, and mucosal homeostasis by maintaining the balance between antipathogen immunity and commensal tolerance. Intestinal homeostasis requires strict regulation of the quantity and activity of local ILC subpopulations. Recent studies demonstrated that changes to ILCs during IBD contribute to disease development. A better understanding of ILC behavior in gastrointestinal homeostasis and inflammation will provide valuable insights into new approaches to IBD treatment. This review summarizes recent research into ILCs in intestinal homeostasis and the latest advances in the understanding of the role of ILCs in IBD, with particular emphasis on the interaction between microbiota and ILC populations and functions.

scholarly journals The role and pathophysiological relevance of membrane transporter PepT1 in intestinal inflammation and inflammatory bowel disease

2012 ◽  
Vol 302 (5) ◽  
pp. G484-G492 ◽  
Author(s):  
Sarah A. Ingersoll ◽  
Saravanan Ayyadurai ◽  
Moiz A. Charania ◽  
Hamed Laroui ◽  
Yutao Yan ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Bowel Disease ◽  
Intestinal Inflammation ◽  
Innate Immune ◽  
Peptide Transport ◽  
Innate Immune Responses ◽  
Colon Cells ◽  
Proinflammatory Responses ◽  
Inflammatory Bowel ◽  
Chronic Intestinal Inflammation

Intestinal inflammation is characterized by epithelial disruption, leading to loss of barrier function and the recruitment of immune cells, including neutrophils. Although the mechanisms are not yet completely understood, interactions between environmental and immunological factors are thought to be critical in the initiation and progression of intestinal inflammation. In recent years, it has become apparent that the di/tripeptide transporter PepT1 may play an important role in the pathogenesis of such inflammation. In healthy individuals, PepT1 is primarily expressed in the small intestine and transports di/tripeptides for metabolic purposes. However, during chronic inflammation such as that associated with inflammatory bowel disease, PepT1 expression is upregulated in the colon, wherein the protein is normally expressed either minimally or not at all. Several recent studies have shown that PepT1 binds to and transports various bacterial di/tripeptides into colon cells, leading to activation of downstream proinflammatory responses via peptide interactions with innate immune receptors. In the present review, we examine the relationship between colonic PepT1-mediated peptide transport in the colon and activation of innate immune responses during disease. It is important to understand the mechanisms of PepT1 action during chronic intestinal inflammation to develop future therapies addressing inappropriate immune activation in the colon.

scholarly journals Loss of Nckx3 Exacerbates Experimental DSS-Induced Colitis in Mice through p53/NF-κB Pathway

2021 ◽  
Vol 22 (5) ◽  
pp. 2645
Author(s):  
Dinh Nam Tran ◽  
Seon Myeong Go ◽  
Seon-Mi Park ◽  
Eui-Man Jung ◽  
Eui-Bae Jeung
Keyword(s):  
Immune Response ◽  
Cellular Proliferation ◽  
Intestinal Inflammation ◽  
Critical Role ◽  
Experimental Colitis ◽  
Innate Immune ◽  
Inflammatory Conditions ◽  
Bowel Diseases ◽  
Inflammatory Bowel ◽  
Microarray Analyses

Inflammatory bowel diseases (IBDs) comprises a range of chronic inflammatory conditions of the intestinal tract. The incidence and prevalence of IBDs are increasing worldwide, but the precise etiology of these diseases is not completely understood. Calcium signaling plays a regulatory role in cellular proliferation. Nckx3, a potassium-dependent Na+/Ca2+ exchanger, is not only expressed in the brain but also in the aortic, uterine, and intestinal tissues, which contain abundant smooth muscle cells. This study investigated the role of Nckx3 in intestinal inflammation. Microarray analyses revealed the upregulation of the innate immune response-associated genes in the duodenum of Nckx3 knockout (KO) mice. The Nckx3 KO mice also showed an increase in IBD- and tumorigenesis-related genes. Using dextran sodium sulfate (DSS)-induced experimental colitis mice models, the Nckx3 KO mice showed severe colitis. Furthermore, the pathways involving p53 and NF-κB signaling were significantly upregulated by the absence of Nckx3. Overall, Nckx3 plays a critical role in the innate immune and immune response and may be central to the pathogenesis of IBD.

scholarly journals Anthocyanins and intestinal barrier function: a review

2019 ◽  
Vol 5 ◽  
pp. 18-30 ◽  
Author(s):  
Jonathan C. Valdez ◽  
Bradley W. Bolling
Keyword(s):  
Barrier Function ◽  
Intestinal Inflammation ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Barrier Dysfunction ◽  
Intestinal Barrier Dysfunction ◽  
Bowel Diseases ◽  
Inflammatory Bowel ◽  
Berry Anthocyanins ◽  
Chronic Intestinal Inflammation

Chronic intestinal inflammation, occurring in inflammatory bowel diseases (IBD), is associated with compromised intestinal barrier function. Inflammatory cytokines disrupt tight junctions and increase paracellular permeability of luminal antigens. Thus, chronic intestinal barrier dysfunction hinders the resolution of inflammation. Dietary approaches may help mitigate intestinal barrier dysfunction and chronic inflammation. A growing body of work in rodent models of colitis has demonstrated that berry consumption inhibits chronic intestinal inflammation. Berries are a rich dietary source of polyphenolic compounds, particularly anthocyanins. However, berry anthocyanins have limited bioavailability and are extensively metabolized by the gut microbiota and host tissue. This review summarizes the literature regarding the beneficial functions of anthocyanin-rich berries in treating and preventing IBD. Here, we will establish the role of barrier function in the pathogenesis of IBD and how dietary anthocyanins and their known microbial catabolites modulate intestinal barrier function.

scholarly journals Thymus leukemia antigen controls intraepithelial lymphocyte function and inflammatory bowel disease

2008 ◽  
Vol 105 (46) ◽  
pp. 17931-17936 ◽  
Author(s):  
Danyvid Olivares-Villagómez ◽  
Yanice V. Mendez-Fernandez ◽  
Vrajesh V. Parekh ◽  
Saif Lalani ◽  
Tiffaney L. Vincent ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Bowel Disease ◽  
Intestinal Inflammation ◽  
Genetic Model ◽  
Critical Role ◽  
Intraepithelial Lymphocytes ◽  
Lymphocyte Function ◽  
Intestinal Epithelial ◽  
Inflammatory Bowel

Intestinal intraepithelial lymphocytes (IEL) bear a partially activated phenotype that permits them to rapidly respond to antigenic insults. However, this phenotype also implies that IEL must be highly controlled to prevent misdirected immune reactions. It has been suggested that IEL are regulated through the interaction of the CD8αα homodimer with the thymus leukemia (TL) antigen expressed by intestinal epithelial cells. We have generated and characterized mice genetically-deficient in TL expression. Our findings show that TL expression has a critical role in maintaining IEL effector functions. Also, TL deficiency accelerated colitis in a genetic model of inflammatory bowel disease. These findings reveal an important regulatory role of TL in controlling IEL function and intestinal inflammation.

Immunological Regulation of Intestinal Fibrosis in Inflammatory Bowel Disease

2021 ◽  
Author(s):  
Giorgos Bamias ◽  
Theresa T Pizarro ◽  
Fabio Cominelli
Keyword(s):  
Inflammatory Bowel Disease ◽  
Bowel Disease ◽  
Large Scale ◽  
Intestinal Inflammation ◽  
Temporal Association ◽  
Stricture Formation ◽  
Intestinal Fibrosis ◽  
Matrix Deposition ◽  
Inflammatory Bowel ◽  
Chronic Intestinal Inflammation

Abstract Intestinal fibrosis is a late-stage phenotype of inflammatory bowel disease (IBD), which underlies most of the long-term complications and surgical interventions in patients, particularly those with Crohn’s disease. Despite these issues, antifibrotic therapies are still scarce, mainly due to the current lack of understanding concerning the pathogenetic mechanisms that mediate fibrogenesis in patients with chronic intestinal inflammation. In the current review, we summarize recent evidence regarding the cellular and molecular factors of innate and adaptive immunity that are considered critical for the initiation and amplification of extracellular matrix deposition and stricture formation. We focus on the role of cytokines by dissecting the pro- vs antifibrotic components of the immune response, while taking into consideration their temporal association to the progressive stages of the natural history of IBD. We critically present evidence from animal models of intestinal fibrosis and analyze inflammation-fibrosis interactions that occur under such experimental scenarios. In addition, we comment on recent findings from large-scale, single-cell profiling of fibrosis-relevant populations in IBD patients. Based on such evidence, we propose future potential targets for antifibrotic therapies to treat patients with IBD.

scholarly journals Unique Regulation of Enterocyte Brush Border Membrane Na-Glutamine and Na-Alanine Co-Transport by Peroxynitrite during Chronic Intestinal Inflammation

2019 ◽  
Vol 20 (6) ◽  
pp. 1504 ◽  
Author(s):  
Subha Arthur ◽  
Palanikumar Manoharan ◽  
Shanmuga Sundaram ◽  
M Rahman ◽  
Balasubramanian Palaniappan ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Brush Border ◽  
Brush Border Membrane ◽  
Intestinal Inflammation ◽  
Intestinal Epithelial Cells ◽  
Rabbit Model ◽  
Intestinal Epithelial ◽  
Mechanism Of Inhibition ◽  
Chronic Intestinal Inflammation

Na-amino acid co-transporters (NaAAcT) are uniquely affected in rabbit intestinal villus cell brush border membrane (BBM) during chronic intestinal inflammation. Specifically, Na-alanine co-transport (ASCT1) is inhibited secondary to a reduction in the affinity of the co-transporter for alanine, whereas Na-glutamine co-transport (B0AT1) is inhibited secondary to a reduction in BBM co-transporter numbers. During chronic intestinal inflammation, there is abundant production of the potent oxidant peroxynitrite (OONO). However, whether OONO mediates the unique alteration in NaAAcT in intestinal epithelial cells during chronic intestinal inflammation is unknown. In this study, ASCT1 and B0AT1 were inhibited by OONO in vitro. The mechanism of inhibition of ASCT1 by OONO was secondary to a reduction in the affinity of the co-transporter for alanine, and secondary to a reduction in the number of co-transporters for B0AT1, which were further confirmed by Western blot analyses. In conclusion, peroxynitrite inhibited both BBM ASCT1 and B0AT1 in intestinal epithelial cells but by different mechanisms. These alterations in the villus cells are similar to those seen in the rabbit model of chronic enteritis. Therefore, this study indicates that peroxynitrite may mediate the inhibition of ASCT1 and B0AT1 during inflammation, when OONO levels are known to be elevated in the mucosa.

scholarly journals Roles of Autophagy-Related Genes in the Pathogenesis of Inflammatory Bowel Disease

Cells ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 77 ◽  
Author(s):  
Sup Kim ◽  
Hyuk Eun ◽  
Eun-Kyeong Jo
Keyword(s):  
Inflammatory Bowel Disease ◽  
Bowel Disease ◽  
Intestinal Inflammation ◽  
Paneth Cell ◽  
Conditional Knockout ◽  
Intestinal Homeostasis ◽  
Genetic Studies ◽  
Inflammatory Bowel ◽  
Direct Targeting ◽  
Catabolic Process

Autophagy is an intracellular catabolic process that is essential for a variety of cellular responses. Due to its role in the maintenance of biological homeostasis in conditions of stress, dysregulation or disruption of autophagy may be linked to human diseases such as inflammatory bowel disease (IBD). IBD is a complicated inflammatory colitis disorder; Crohn’s disease and ulcerative colitis are the principal types. Genetic studies have shown the clinical relevance of several autophagy-related genes (ATGs) in the pathogenesis of IBD. Additionally, recent studies using conditional knockout mice have led to a comprehensive understanding of ATGs that affect intestinal inflammation, Paneth cell abnormality and enteric pathogenic infection during colitis. In this review, we discuss the various ATGs involved in macroautophagy and selective autophagy, including ATG16L1, IRGM, LRRK2, ATG7, p62, optineurin and TFEB in the maintenance of intestinal homeostasis. Although advances have been made regarding the involvement of ATGs in maintaining intestinal homeostasis, determining the precise contribution of autophagy has remained elusive. Recent efforts based on direct targeting of ATGs and autophagy will further facilitate the development of new therapeutic opportunities for IBD.

scholarly journals Deficiency in the anti-apoptotic protein DJ-1 promotes intestinal epithelial cell apoptosis and aggravates inflammatory bowel disease via p53

2020 ◽  
Vol 295 (13) ◽  
pp. 4237-4251 ◽  
Author(s):  
Jie Zhang ◽  
Min Xu ◽  
Weihua Zhou ◽  
Dejian Li ◽  
Hong Zhang ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Epithelial Cell ◽  
Bowel Disease ◽  
Intestinal Epithelial Cell ◽  
Intestinal Inflammation ◽  
Intestinal Epithelial ◽  
P53 Expression ◽  
Inflammatory Bowel

Parkinson disease autosomal recessive, early onset 7 (PARK7 or DJ-1) is involved in multiple physiological processes and exerts anti-apoptotic effects on multiple cell types. Increased intestinal epithelial cell (IEC) apoptosis and excessive activation of the p53 signaling pathway is a hallmark of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD). However, whether DJ-1 plays a role in colitis is unclear. To determine whether DJ-1 deficiency is involved in the p53 activation that results in IEC apoptosis in colitis, here we performed immunostaining, real-time PCR, and immunoblotting analyses to assess DJ-1 expression in human UC and CD samples. In the inflamed intestines of individuals with IBD, DJ-1 expression was decreased and negatively correlated with p53 expression. DJ-1 deficiency significantly aggravated colitis, evidenced by increased intestinal inflammation and exacerbated IEC apoptosis. Moreover, DJ-1 directly interacted with p53, and reduced DJ-1 levels increased p53 levels both in vivo and in vitro and were associated with decreased p53 degradation via the lysosomal pathway. We also induced experimental colitis with dextran sulfate sodium in mice and found that compared with DJ-1−/− mice, DJ-1−/−p53−/− mice have reduced apoptosis and inflammation and increased epithelial barrier integrity. Furthermore, pharmacological inhibition of p53 relieved inflammation in the DJ-1−/− mice. In conclusion, reduced DJ-1 expression promotes inflammation and IEC apoptosis via p53 in colitis, suggesting that the modulation of DJ-1 expression may be a potential therapeutic strategy for managing colitis.

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