Vitamin D and colorectal cancer: Chemopreventive perspectives through the gut microbiota and the immune system

The gastrointestinal tract (GIT) of humans and animals is host to a complex community of different microorganisms whose activities significantly influence host nutrition and health through enhanced metabolic capabilities, protection against pathogens, and regulation of the gastrointestinal development and immune system. New molecular technologies and concepts have revealed distinct interactions between the gut microbiota and dietary amino acids (AAs) especially in relation to AA metabolism and utilization in resident bacteria in the digestive tract, and these interactions may play significant roles in host nutrition and health as well as the efficiency of dietary AA supplementation. After the protein is digested and AAs and peptides are absorbed in the small intestine, significant levels of endogenous and exogenous nitrogenous compounds enter the large intestine through the ileocaecal junction. Once they move in the colonic lumen, these compounds are not markedly absorbed by the large intestinal mucosa, but undergo intense proteolysis by colonic microbiota leading to the release of peptides and AAs and result in the production of numerous bacterial metabolites such as ammonia, amines, short-chain fatty acids (SCFAs), branched-chain fatty acids (BCFAs), hydrogen sulfide, organic acids, and phenols. These metabolites influence various signaling pathways in epithelial cells, regulate the mucosal immune system in the host, and modulate gene expression of bacteria which results in the synthesis of enzymes associated with AA metabolism. This review aims to summarize the current literature relating to how the interactions between dietary amino acids and gut microbiota may promote host nutrition and health.

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Microbiota-Immune System Interactions in Human Neurological Disorders

CNS & Neurological Disorders - Drug Targets ◽

10.2174/1871527319666200726222138 ◽

2020 ◽

Vol 19 (7) ◽

pp. 509-526

Author(s):

Qin Huang ◽

Fang Yu ◽

Di Liao ◽

Jian Xia

Keyword(s):

Immune System ◽

Gut Microbiota ◽

Neurological Disorders ◽

Brain Function ◽

Neurological Diseases ◽

Host Immune System ◽

Gut Dysbiosis ◽

Characteristic Features ◽

Novel Therapeutic Strategies

: Recent studies implicate microbiota-brain communication as an essential factor for physiology and pathophysiology in brain function and neurodevelopment. One of the pivotal mechanisms about gut to brain communication is through the regulation and interaction of gut microbiota on the host immune system. In this review, we will discuss the role of microbiota-immune systeminteractions in human neurological disorders. The characteristic features in the development of neurological diseases include gut dysbiosis, the disturbed intestinal/Blood-Brain Barrier (BBB) permeability, the activated inflammatory response, and the changed microbial metabolites. Neurological disorders contribute to gut dysbiosis and some relevant metabolites in a top-down way. In turn, the activated immune system induced by the change of gut microbiota may deteriorate the development of neurological diseases through the disturbed gut/BBB barrier in a down-top way. Understanding the characterization and identification of microbiome-immune- brain signaling pathways will help us to yield novel therapeutic strategies by targeting the gut microbiome in neurological disease.

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Obesity and Colorectal Cancer Risk: Impact of the Gut Microbiota and Weight-Loss Diets~!2009-09-07~!2009-09-23~!2010-07-13~!

The Open Obesity Journal ◽

10.2174/1876823701002020050 ◽

2010 ◽

Vol 2 (2) ◽

pp. 50-62 ◽

Cited By ~ 1

Author(s):

Harry J. Flint ◽

R. John Wallace

Keyword(s):

Colorectal Cancer ◽

Weight Loss ◽

Cancer Risk ◽

Gut Microbiota ◽

Colorectal Cancer Risk

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Microbial Metabolites in Colorectal Cancer: Basic and Clinical Implications

Metabolites ◽

10.3390/metabo11030159 ◽

2021 ◽

Vol 11 (3) ◽

pp. 159

Author(s):

Yao Peng ◽

Yuqiang Nie ◽

Jun Yu ◽

Chi Chun Wong

Keyword(s):

Colorectal Cancer ◽

Gut Microbiota ◽

Cancer Diagnosis ◽

Intestinal Tract ◽

Clinical Applications ◽

Diagnosis And Treatment ◽

Clinical Implications ◽

Microbial Metabolites ◽

Colorectal Tumorigenesis ◽

Technology Studies

Colorectal cancer (CRC) is one of the leading cancers that cause cancer-related deaths worldwide. The gut microbiota has been proved to show relevance with colorectal tumorigenesis through microbial metabolites. By decomposing various dietary residues in the intestinal tract, gut microbiota harvest energy and produce a variety of metabolites to affect the host physiology. However, some of these metabolites are oncogenic factors for CRC. With the advent of metabolomics technology, studies profiling microbiota-derived metabolites have greatly accelerated the progress in our understanding of the host-microbiota metabolism interactions in CRC. In this review, we briefly summarize the present metabolomics techniques in microbial metabolites researches and the mechanisms of microbial metabolites in CRC pathogenesis, furthermore, we discuss the potential clinical applications of microbial metabolites in cancer diagnosis and treatment.

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Postoperative Complications Are Associated with Long-Term Changes in the Gut Microbiota Following Colorectal Cancer Surgery

Life ◽

10.3390/life11030246 ◽

2021 ◽

Vol 11 (3) ◽

pp. 246

Author(s):

Felix C.F. Schmitt ◽

Martin Schneider ◽

William Mathejczyk ◽

Markus A. Weigand ◽

Jane C. Figueiredo ◽

...

Keyword(s):

Colorectal Cancer ◽

Postoperative Complications ◽

Gut Microbiota ◽

Gut Microbiome ◽

Tumor Resection ◽

Microbial Composition ◽

Colorectal Cancer Surgery ◽

Long Term Changes ◽

Stool Samples

Changes in the gut microbiome have already been associated with postoperative complications in major abdominal surgery. However, it is still unclear whether these changes are transient or a long-lasting effect. Therefore, the aim of this prospective clinical pilot study was to examine long-term changes in the gut microbiota and to correlate these changes with the clinical course of the patient. Methods: In total, stool samples of 62 newly diagnosed colorectal cancer patients undergoing primary tumor resection were analyzed by 16S-rDNA next-generation sequencing. Stool samples were collected preoperatively in order to determine the gut microbiome at baseline as well as at 6, 12, and 24 months thereafter to observe longitudinal changes. Postoperatively, the study patients were separated into two groups—patients who suffered from postoperative complications (n = 30) and those without complication (n = 32). Patients with postoperative complications showed a significantly stronger reduction in the alpha diversity starting 6 months after operation, which does not resolve, even after 24 months. The structure of the microbiome was also significantly altered from baseline at six-month follow-up in patients with complications (p = 0.006). This was associated with a long-lasting decrease of a large number of species in the gut microbiota indicating an impact in the commensal microbiota and a long-lasting increase of Fusobacterium ulcerans. The microbial composition of the gut microbiome shows significant changes in patients with postoperative complications up to 24 months after surgery.

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Interplay between the Gut Microbiota and Inflammatory Mediators in the Development of Colorectal Cancer

Cancers ◽

10.3390/cancers13040734 ◽

2021 ◽

Vol 13 (4) ◽

pp. 734

Author(s):

Gwangbeom Heo ◽

Yunna Lee ◽

Eunok Im

Keyword(s):

Colorectal Cancer ◽

Gut Microbiota ◽

Inflammatory Mediators ◽

Tumor Metastasis ◽

Intestinal Tract ◽

Fecal Microbiota Transplantation ◽

Fecal Microbiota ◽

Therapeutic Interventions ◽

Potential Therapeutic Target ◽

Necrosis Factor

Inflammatory mediators modulate inflammatory pathways during the development of colorectal cancer. Inflammatory mediators secreted by both immune and tumor cells can influence carcinogenesis, progression, and tumor metastasis. The gut microbiota, which colonize the entire intestinal tract, especially the colon, are closely linked to colorectal cancer through an association with inflammatory mediators such as tumor necrosis factor, nuclear factor kappa B, interleukins, and interferons. This association may be a potential therapeutic target, since therapeutic interventions targeting the gut microbiota have been actively investigated in both the laboratory and in clinics and include fecal microbiota transplantation and probiotics.

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