Role of Commensal Enteric Bacteria in Intestinal Inflammation: Lessons from Animal Models

RNA helicases play roles in various essential biological processes such as RNA splicing and editing. Recent in vitro studies show that RNA helicases are involved in immune responses toward viruses, serving as viral RNA sensors or immune signaling adaptors. However, there is still a lack of in vivo data to support the tissue- or cell-specific function of RNA helicases owing to the lethality of mice with complete knockout of RNA helicases; further, there is a lack of evidence about the antibacterial role of helicases. Here, we investigated the in vivo role of Dhx15 in intestinal antibacterial responses by generating mice that were intestinal epithelial cell (IEC)-specific deficient for Dhx15 (Dhx15 f/f Villin1-cre, Dhx15ΔIEC). These mice are susceptible to infection with enteric bacteria Citrobacter rodentium (C. rod), owing to impaired α-defensin production by Paneth cells. Moreover, mice with Paneth cell-specific depletion of Dhx15 (Dhx15 f/f Defensinα6-cre, Dhx15ΔPaneth) are more susceptible to DSS (dextran sodium sulfate)-induced colitis, which phenocopy Dhx15ΔIEC mice, due to the dysbiosis of the intestinal microbiota. In humans, reduced protein levels of Dhx15 are found in ulcerative colitis (UC) patients. Taken together, our findings identify a key regulator of Wnt-induced α-defensins in Paneth cells and offer insights into its role in the antimicrobial response as well as intestinal inflammation.

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Role of CD5 expression on TCRγδ T cell-differentiation and development of chronic intestinal inflammation

Gastroenterology ◽

10.1016/s0016-5085(01)82566-x ◽

2001 ◽

Vol 120 (5) ◽

pp. A517-A517

Author(s):

A MIZOGUCHI ◽

E MIZOGUCHI ◽

Y DEJONG ◽

H TAKEDATSU ◽

F PREFFER ◽

...

Keyword(s):

Cell Differentiation ◽

T Cell ◽

Intestinal Inflammation ◽

T Cell Differentiation ◽

Chronic Intestinal Inflammation

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Cellular and animal models in pheochromocytoma/paragangliomas research: role of microenvironment

Endocrine Abstracts ◽

10.1530/endoabs.40.l13 ◽

2016 ◽

Author(s):

M Mannelli ◽

E Rapizzi ◽

L Canu ◽

T Ercolino ◽

V Giache

Keyword(s):

Animal Models

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Urban Wastewater Discharge and Bacteriological Quality of Receiving Coastal Waters: Processes and Modelling

Water Science & Technology ◽

10.2166/wst.1993.0306 ◽

1993 ◽

Vol 27 (12) ◽

pp. 223-226

Author(s):

J.-F. Guillaud ◽

M. Pommepuy ◽

E. Dupray ◽

J.-C. Salomon ◽

B. Thouvenin

Keyword(s):

Coastal Zone ◽

Coastal Waters ◽

Wastewater Treatment Plants ◽

Enteric Bacteria ◽

Wastewater Discharge ◽

Urban Wastewater ◽

Bacteria Transport

The aim of this paper is to present some results of bacterial studies which were developed by IFREMER in coastal discharge areas of urban wastewaters; they are focused on the determination of bacterial inputs by wastewater treatment plants, the role of environmental factors on the enteric bacteria survival in the coastal zone, and the modelling of bacteria transport and disappearance in order to provide useful management information for minimizing faecal pollution in the coastal zone.

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Bioengineered in vitro Vascular Models for Applications in Interventional Radiology

Current Pharmaceutical Design ◽

10.2174/1381612824666180416114325 ◽

2019 ◽

Vol 24 (45) ◽

pp. 5367-5374 ◽

Cited By ~ 1

Author(s):

Xiaoyun Li ◽

Seyed M. Moosavi-Basri ◽

Rahul Sheth ◽

Xiaoying Wang ◽

Yu S. Zhang

Keyword(s):

Interventional Radiology ◽

Animal Models ◽

Blood Vessels ◽

In Vitro Models ◽

The Past ◽

Endovascular Interventions ◽

Conventional Animal ◽

Vascular Structures

The role of endovascular interventions has progressed rapidly over the past several decades. While animal models have long-served as the mainstay for the advancement of this field, the use of in vitro models has become increasingly widely adopted with recent advances in engineering technologies. Here, we review the strategies, mainly including bioprinting and microfabrication, which allow for fabrication of biomimetic vascular models that will potentially serve to supplement the conventional animal models for convenient investigations of endovascular interventions. Besides normal blood vessels, those in diseased states, such as thrombosis, may also be modeled by integrating cues that simulate the microenvironment of vascular disorders. These novel engineering strategies for the development of biomimetic in vitro vascular structures will possibly enable unconventional means of studying complex endovascular intervention problems that are otherwise hard to address using existing models.

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The Role of the Transsulfuration Pathway in Non-Alcoholic Fatty Liver Disease

Journal of Clinical Medicine ◽

10.3390/jcm10051081 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1081

Author(s):

Mikkel Parsberg Werge ◽

Adrian McCann ◽

Elisabeth Douglas Galsgaard ◽

Dorte Holst ◽

Anne Bugge ◽

...

Keyword(s):

Liver Disease ◽

Animal Models ◽

Fatty Liver ◽

Fatty Liver Disease ◽

Alcoholic Fatty Liver ◽

Precise Control ◽

Transsulfuration Pathway ◽

Global Population ◽

Alcoholic Fatty Liver Disease

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing and approximately 25% of the global population may have NAFLD. NAFLD is associated with obesity and metabolic syndrome, but its pathophysiology is complex and only partly understood. The transsulfuration pathway (TSP) is a metabolic pathway regulating homocysteine and cysteine metabolism and is vital in controlling sulfur balance in the organism. Precise control of this pathway is critical for maintenance of optimal cellular function. The TSP is closely linked to other pathways such as the folate and methionine cycles, hydrogen sulfide (H2S) and glutathione (GSH) production. Impaired activity of the TSP will cause an increase in homocysteine and a decrease in cysteine levels. Homocysteine will also be increased due to impairment of the folate and methionine cycles. The key enzymes of the TSP, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), are highly expressed in the liver and deficient CBS and CSE expression causes hepatic steatosis, inflammation, and fibrosis in animal models. A causative link between the TSP and NAFLD has not been established. However, dysfunctions in the TSP and related pathways, in terms of enzyme expression and the plasma levels of the metabolites (e.g., homocysteine, cystathionine, and cysteine), have been reported in NAFLD and liver cirrhosis in both animal models and humans. Further investigation of the TSP in relation to NAFLD may reveal mechanisms involved in the development and progression of NAFLD.

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Role of Dietary Nutritional Treatment on Hepatic and Intestinal Damage in Transplantation with Steatotic and Non-Steatotic Liver Grafts from Brain Dead Donors

Nutrients ◽

10.3390/nu13082554 ◽

2021 ◽

Vol 13 (8) ◽

pp. 2554

Author(s):

Marc Micó-Carnero ◽

Araní Casillas-Ramírez ◽

Albert Caballeria-Casals ◽

Carlos Rojano-Alfonso ◽

Alfredo Sánchez-González ◽

...

Keyword(s):

Growth Factor ◽

Gut Microbiota ◽

Intestinal Inflammation ◽

Mucosal Damage ◽

Hepatic Damage ◽

Intestinal Damage ◽

Edema Formation ◽

Steatotic Liver ◽

Damage And Failure

Herein, we investigate whether: (1) the administration of glucose or a lipid emulsion is useful in liver transplantation (LT) using steatotic (induced genetically or nutritionally) or non-steatotic livers from donors after brain death (DBDs); and (2) any such benefits are due to reductions in intestinal damage and consequently to gut microbiota preservation. In recipients from DBDs, we show increased hepatic damage and failure in the maintenance of ATP, glycogen, phospholipid and growth factor (HGF, IGF1 and VEGFA) levels, compared to recipients from non-DBDs. In recipients of non-steatotic grafts from DBDs, the administration of glucose or lipids did not protect against hepatic damage. This was associated with unchanged ATP, glycogen, phospholipid and growth factor levels. However, the administration of lipids in steatotic grafts from DBDs protected against damage and ATP and glycogen drop and increased phospholipid levels. This was associated with increases in growth factors. In all recipients from DBDs, intestinal inflammation and damage (evaluated by LPS, vascular permeability, mucosal damage, TLR4, TNF, IL1, IL-10, MPO, MDA and edema formation) was not shown. In such cases, potential changes in gut microbiota would not be relevant since neither inflammation nor damage was evidenced in the intestine following LT in any of the groups evaluated. In conclusion, lipid treatment is the preferable nutritional support to protect against hepatic damage in steatotic LT from DBDs; the benefits were independent of alterations in the recipient intestine.

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Inflammation and Atherosclerosis

Cells ◽

10.3390/cells10051197 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1197

Author(s):

Klaus Ley

Keyword(s):

Clinical Trials ◽

Animal Models ◽

Basic Science ◽

Translational Science ◽

Special Issue

This 11-chapter Special Issue of Cells spans the gamut from basic science in mechanistic animal models to translational science to outcomes of clinical trials, all focused on the role of inflammation in atherosclerosis [...]

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