scholarly journals Guts and Gall: Bile Acids in Regulation of Intestinal Epithelial Function in Health and Disease

2018 ◽  
Vol 98 (4) ◽  
pp. 1983-2023 ◽  
Author(s):  
Peter Hegyi ◽  
Jozsef Maléth ◽  
Julian R. Walters ◽  
Alan F. Hofmann ◽  
Stephen J. Keely

Epithelial cells line the entire surface of the gastrointestinal tract and its accessory organs where they primarily function in transporting digestive enzymes, nutrients, electrolytes, and fluid to and from the luminal contents. At the same time, epithelial cells are responsible for forming a physical and biochemical barrier that prevents the entry into the body of harmful agents, such as bacteria and their toxins. Dysregulation of epithelial transport and barrier function is associated with the pathogenesis of a number of conditions throughout the intestine, such as inflammatory bowel disease, chronic diarrhea, pancreatitis, reflux esophagitis, and cancer. Driven by discovery of specific receptors on intestinal epithelial cells, new insights into mechanisms that control their synthesis and enterohepatic circulation, and a growing appreciation of their roles as bioactive bacterial metabolites, bile acids are currently receiving a great deal of interest as critical regulators of epithelial function in health and disease. This review aims to summarize recent advances in this field and to highlight how bile acids are now emerging as exciting new targets for disease intervention.

2018 ◽  
Author(s):  
Roni Lehmann-Werman ◽  
Aviad Zick ◽  
Cloud Paweletz ◽  
Marisa Welch ◽  
Ayala Hubert ◽  
...  

AbstractEpithelial cells of the intestine undergo rapid turnover and are thought to be cleared via stool. Disruption of tissue architecture, as occurs in colorectal cancer (CRC), results in the release of material from dying intestinal epithelial cells to blood. This phenomenon could be utilized for diagnosis and monitoring of intestinal diseases, if circulating cell-free DNA (cfDNA) derived from intestinal cells could be specifically identified. Here we describe two genomic loci that are unmethylated specifically in intestinal epithelial cells, allowing for sensitive and specific detection of DNA derived from such cells. As expected, intestinal DNA is found in stool, but not in plasma, of healthy individuals. Patients with inflammatory bowel disease (IBD) have minimal amounts of intestinal cfDNA in the plasma, whereas patients with advanced CRC show a strong signal. The intestinal markers are not elevated in plasma samples from patients with pancreatic ductal adenocarcinoma (PDAC), and a combination of intestine- and pancreas-specific markers allowed for robust differentiation between plasma cfDNA derived from CRC and PDAC patients. Intestinal DNA markers provide a mutation-independent tool for monitoring intestinal dynamics in health and disease.


2021 ◽  
Vol 22 (4) ◽  
pp. 1780
Author(s):  
Maria Chiara di Gregorio ◽  
Jacopo Cautela ◽  
Luciano Galantini

Bile acids (BAs) are facial amphiphiles synthesized in the body of all vertebrates. They undergo the enterohepatic circulation: they are produced in the liver, stored in the gallbladder, released in the intestine, taken into the bloodstream and lastly re-absorbed in the liver. During this pathway, BAs are modified in their molecular structure by the action of enzymes and bacteria. Such transformations allow them to acquire the chemical–physical properties needed for fulling several activities including metabolic regulation, antimicrobial functions and solubilization of lipids in digestion. The versatility of BAs in the physiological functions has inspired their use in many bio-applications, making them important tools for active molecule delivery, metabolic disease treatments and emulsification processes in food and drug industries. Moreover, moving over the borders of the biological field, BAs have been largely investigated as building blocks for the construction of supramolecular aggregates having peculiar structural, mechanical, chemical and optical properties. The review starts with a biological analysis of the BAs functions before progressively switching to a general overview of BAs in pharmacology and medicine applications. Lastly the focus moves to the BAs use in material science.


2016 ◽  
Vol 7 (10) ◽  
pp. 4388-4399 ◽  
Author(s):  
Anouk Kaulmann ◽  
Sébastien Planchon ◽  
Jenny Renaut ◽  
Yves-Jacques Schneider ◽  
Lucien Hoffmann ◽  
...  

Proteomic response of intestinal cells as a model of inflammatory bowel diseases to digested plum and cabbage rich in polyphenols and carotenoids.


Author(s):  
Dina Cosme ◽  
Maria Manuela Estevinho ◽  
Florian Rieder ◽  
Fernando Magro

Background: Several potassium channels (KCs) have been described throughout the gastrointestinal tract. Notwithstanding, their contribution to both physiologic and pathophysiologic conditions, as inflammatory bowel disease (IBD), remains underexplored. Therefore, we aim to systematically review, for the first time, the evidence on the characteristics and modulation of KCs in intestinal epithelial cells (IECs). Methods: PubMed, Scopus and Web of Science were searched to identify studies focusing on KCs and their modulation in IECs. The included studies were assessed using a reporting inclusiveness checklist. Results: From the 745 identified records, 73 met the inclusion criteria; their reporting inclusiveness was moderate-high. Some studies described the physiological role of KCs, while others explored their importance in pathological settings. Globally, in IBD animal models, apical KCa1.1 channels, responsible for luminal secretion, were upregulated. In human colonocytes, basolateral KCa3.1 channels were downregulated. The pharmacological inhibition of K2P and Kv influenced intestinal barrier function, promoting inflammation. Conclusion: Evidence suggests a strong association between KCs expression and secretory mechanisms in human and animal IECs. Further research is warranted to explore the usefulness of KC pharmacological modulation as a therapeutic target.


2009 ◽  
Vol 296 (4) ◽  
pp. G850-G859 ◽  
Author(s):  
Michio Onizawa ◽  
Takashi Nagaishi ◽  
Takanori Kanai ◽  
Ken-ichi Nagano ◽  
Shigeru Oshima ◽  
...  

Treatment with anti-TNF-α MAb has been accepted as a successful maintenance therapy for patients with inflammatory bowel diseases (IBD). Moreover, it has been recently reported that blockade of TNF receptor (TNFR) 1 signaling in infiltrating hematopoietic cells may prevent the development of colitis-associated cancer (CAC). However, it remains unclear whether the TNF-α signaling in epithelial cells is involved in the development of CAC. To investigate this, we studied the effects of anti-TNF-α MAb in an animal model of CAC by administration of azoxymethane (AOM) followed by sequential dextran sodium sulfate (DSS) ingestion. We observed that the NF-κB pathway is activated in colonic epithelia from DSS-administered mice in association with upregulation of TNFR2 rather than TNFR1. Immunoblot analysis also revealed that the TNFR2 upregulation accompanied by the NF-κB activation is further complicated in CAC tissues induced in AOM/DSS-administered mice compared with the nontumor area. Such NF-κB activity in the epithelial cells is significantly suppressed by the treatment of MP6-XT22, an anti-TNF-α MAb. Despite inability to reduce the severity of colitis, sequential administration of MP6-XT22 reduced the numbers and size of tumors in association with the NF-κB inactivation. Taken together, present studies suggest that the TNFR2 signaling in intestinal epithelial cells may be directly involved in the development of CAC with persistent colitis and imply that the maintenance therapy with anti-TNF-α MAb may prevent the development of CAC in patients with long-standing IBD.


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