scholarly journals Ecological Structuring of Temperate Bacteriophages in the Inflammatory Bowel Disease-Affected Gut

2020 ◽  
Vol 8 (11) ◽  
pp. 1663
Author(s):  
Hiroki Nishiyama ◽  
Hisashi Endo ◽  
Romain Blanc-Mathieu ◽  
Hiroyuki Ogata

The aim of this study was to elucidate the ecological structure of the human gut temperate bacteriophage community and its role in inflammatory bowel disease (IBD). Temperate bacteriophages make up a large proportion of the human gut microbiota and are likely to play a role in IBD pathogenesis. However, many of these bacteriophages await characterization in reference databases. Therefore, we conducted a large-scale reconstruction of temperate bacteriophage and bacterial genomes from the whole-metagenome sequence data generated by the IBD Multi’omics Database project. By associating phages with their hosts via genome comparisons, we found that temperate bacteriophages infect a phylogenetically wide range of bacteria. The majority of variance in bacteriophage community composition was explained by variation among individuals, but differences in the abundance of temperate bacteriophages were identified between IBD and non-IBD patients. Of note, in active ulcerative colitis patients, temperate bacteriophages infecting Bacteroides uniformis and Bacteroides thetaiotaomicron—two species experimentally proven to be beneficial to gut homeostasis—were over-represented, whereas their hosts were under-represented in comparison with non-IBD patients. Supporting the mounting evidence that gut viral community plays a vital role in IBD, our results show potential association between temperate bacteriophages and IBD pathogenesis.

2019 ◽  
Vol 1 (1) ◽  
pp. 23-27
Author(s):  
Saali Mohammed Lutfi

Microbes are an important component of the microbiology  eco-system in the human gut, which is colonized by 1014 bacteria , ten times more than the human cells. Gut bacteria take  an important role in human health, like  supplying essential nutrients, synthesizing vit. K, aiding in the digestion of cellulose, and promoting angiogenesis and enteric nerve function. However, they can also be potentially harmful due to the change of their composition when the gut ecosystem undergoes abnormal changes in the light of the use of antibiotics, illness, stress, aging, bad dietary habits, and lifestyle. Dysbiosis of the gut bacteria communities can cause many chronic diseases, such as inflammatory bowel disease, obesity, cancer, and autism.


2011 ◽  
Vol 140 (5) ◽  
pp. S-350-S-351
Author(s):  
Stephan Brackmann ◽  
Maria E. Pretorius ◽  
Solveig N. Andersen ◽  
Frøydis Langmark ◽  
Ole P.F. Clausen ◽  
...  

Author(s):  
Giorgos Bamias ◽  
Theresa T Pizarro ◽  
Fabio Cominelli

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.


mSystems ◽  
2020 ◽  
Vol 5 (4) ◽  
Author(s):  
Maria I. Rojas ◽  
Giselle S. Cavalcanti ◽  
Katelyn McNair ◽  
Sean Benler ◽  
Amanda T. Alker ◽  
...  

ABSTRACT Many commensal bacteria antagonize each other or their host by producing syringe-like secretion systems called contractile injection systems (CIS). Members of the Bacteroidales family have been shown to produce only one type of CIS—a contact-dependent type 6 secretion system that mediates bacterium-bacterium interactions. Here, we show that a second distinct cluster of genes from Bacteroidales bacteria from the human microbiome may encode yet-uncharacterized injection systems that we term Bacteroidales injection systems (BIS). We found that BIS genes are present in the gut microbiomes of 99% of individuals from the United States and Europe and that BIS genes are more prevalent in the gut microbiomes of healthy individuals than in those individuals suffering from inflammatory bowel disease. Gene clusters similar to that of the BIS mediate interactions between bacteria and diverse eukaryotes, like amoeba, insects, and tubeworms. Our findings highlight the ubiquity of the BIS gene cluster in the human gut and emphasize the relevance of the gut microbiome to the human host. These results warrant investigations into the structure and function of the BIS and how they might mediate interactions between Bacteroidales bacteria and the human host or microbiome. IMPORTANCE To engage with host cells, diverse pathogenic bacteria produce syringe-like structures called contractile injection systems (CIS). CIS are evolutionarily related to the contractile tails of bacteriophages and are specialized to puncture membranes, often delivering effectors to target cells. Although CIS are key for pathogens to cause disease, paradoxically, similar injection systems have been identified within healthy human microbiome bacteria. Here, we show that gene clusters encoding a predicted CIS, which we term Bacteroidales injection systems (BIS), are present in the microbiomes of nearly all adult humans tested from Western countries. BIS genes are enriched within human gut microbiomes and are expressed both in vitro and in vivo. Further, a greater abundance of BIS genes is present within healthy gut microbiomes than in those humans with with inflammatory bowel disease (IBD). Our discovery provides a potentially distinct means by which our microbiome interacts with the human host or its microbiome.


2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Jingjing Kang ◽  
Li Zhang ◽  
Xiao Luo ◽  
Xiangyu Ma ◽  
Gaoying Wang ◽  
...  

Mesenchymal stem cells (MSCs) therapy has been applied to a wide range of diseases with excessive immune response, including inflammatory bowel disease (IBD), owing to its powerful immunosuppression and its ability to repair tissue lesions. Different sources of MSCs show different therapeutic properties. Engineering managements are able to enhance the immunomodulation function and the survival of MSCs involved in IBD. The therapeutic mechanism of MSCs in IBD mainly focuses on cell-to-cell contact and paracrine actions. One of the promising therapeutic options for IBD can focus on exosomes of MSCs. MSCs hold promise for the treatment of IBD-associated colorectal cancer because of their tumor-homing function and chronic inflammation inhibition. Encouraging results have been obtained from clinical trials in IBD and potential challenges caused by MSCs therapy are getting solved. This review can assist investigators better to understand the research progress for enhancing the efficacy of MSCs therapy involved in IBD and CAC.


2017 ◽  
Vol 2 (5) ◽  
Author(s):  
Jonas Halfvarson ◽  
Colin J. Brislawn ◽  
Regina Lamendella ◽  
Yoshiki Vázquez-Baeza ◽  
William A. Walters ◽  
...  

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Fanli Kong ◽  
Yi Cai

The gut microbiome in human is recognized as a “microbial organ” for its roles and contributions in regulating the human homeostasis and metabolism. Gastrointestinal (GI) cancers, especially colorectal cancer (CRC), rank as the most common cancer-related deaths worldwide. Evidences have suggested that the disorder of gut microbiota, also named as “dysbiosis,” is related to the development of a variety of diseases such as inflammatory bowel disease (IBD) and the CRC. However, detailed mechanisms between disease and gut microbiota remain largely unknown. This review introduced the correlation between gastrointestinal diseases and the microbiota in human gut from the recent studies, as well as the roles of microbiota in manipulating the CRC and IBDs development, in order to facilitate future studies and to develop novel methods for the precaution, diagnosis, or even cure of gastrointestinal diseases. Additionally, we also elucidated the possibility of probiotics in treatment against CRC.


2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Pierre Lapaquette ◽  
Jean Guzzo ◽  
Lionel Bretillon ◽  
Marie-Agnès Bringer

Autophagy is an intracellular catabolic pathway essential for the recycling of proteins and larger substrates such as aggregates, apoptotic corpses, or long-lived and superfluous organelles whose accumulation could be toxic for cells. Because of its unique feature to engulf part of cytoplasm in double-membrane cup-shaped structures, which further fuses with lysosomes, autophagy is also involved in the elimination of host cell invaders and takes an active part of the innate and adaptive immune response. Its pivotal role in maintenance of the inflammatory balance makes dysfunctions of the autophagy process having important pathological consequences. Indeed, defects in autophagy are associated with a wide range of human diseases including metabolic disorders (diabetes and obesity), inflammatory bowel disease (IBD), and cancer. In this review, we will focus on interrelations that exist between inflammation and autophagy. We will discuss in particular how mediators of inflammation can regulate autophagy activity and, conversely, how autophagy shapes the inflammatory response. Impact of genetic polymorphisms in autophagy-related gene on inflammatory bowel disease will be also discussed.


2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Martina Perše ◽  
Anton Cerar

Inflammatory bowel disease (IBD) is a complex multifactorial disease of unknown etiology. Thus, dozens of different animal models of IBD have been developed in past decades. Animal models of IBD are valuable and indispensable tools that provide a wide range of options for investigating involvement of various factors into the pathogenesis of IBD and to evaluate different therapeutic options. However, the dextran sulphate sodium (DSS-) induced colitis model has some advantages when compared to other animal models of colitis. It is well appreciated and widely used model of inflammatory bowel disease because of its simplicity. It has many similarities to human IBD, which are mentioned in the paper. In spite of its simplicity and wide applicability, there are also traps that need to be taken into account when using DSS model. As demonstrated in the present paper, various factors may affect susceptibility to DSS-induced lesions and modify results.


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