The role of microbiota in health and diseases is being highlighted by numerous studies since its discovery. Depending on the localized regions, microbiota can be classified into gut, oral, respiratory, and skin microbiota. The microbial communities are in symbiosis with the host, contributing to homeostasis and regulating immune function. However, microbiota dysbiosis can lead to dysregulation of bodily functions and diseases including cardiovascular diseases (CVDs), cancers, respiratory diseases, etc. In this review, we discuss the current knowledge of how microbiota links to host health or pathogenesis. We first summarize the research of microbiota in healthy conditions, including the gut-brain axis, colonization resistance and immune modulation. Then, we highlight the pathogenesis of microbiota dysbiosis in disease development and progression, primarily associated with dysregulation of community composition, modulation of host immune response, and induction of chronic inflammation. Finally, we introduce the clinical approaches that utilize microbiota for disease treatment, such as microbiota modulation and fecal microbial transplantation. 

/pdf/microbiota-in-health-and-diseases-2698gfvn.pdf

Microbiota in health and diseases

Advances in our understanding of how the gut microbiota contributes to human health and diseases have expanded our insight into how microbial composition and function affect the human host. Heart failure is associated with splanchnic circulation congestion, leading to bowel wall oedema and impaired intestinal barrier function. This situation is thought to heighten the overall inflammatory state via increased bacterial translocation and the presence of bacterial products in the systemic blood circulation. Several metabolites produced by gut microorganisms from dietary metabolism have been linked to pathologies such as atherosclerosis, hypertension, heart failure, chronic kidney disease, obesity, and type 2 diabetes mellitus. These findings suggest that the gut microbiome functions like an endocrine organ by generating bioactive metabolites that can directly or indirectly affect host physiology. In this Review, we discuss several newly discovered gut microbial metabolic pathways, including the production of trimethylamine and trimethylamine N-oxide, short-chain fatty acids, and secondary bile acids, that seem to participate in the development and progression of cardiovascular diseases, including heart failure. We also discuss the gut microbiome as a novel therapeutic target for the treatment of cardiovascular disease, and potential strategies for targeting intestinal microbial processes.

/pdf/dietary-metabolism-the-gut-microbiome-and-heart-failure-31qeh6leiq.pdf

Dietary metabolism, the gut microbiome, and heart failure

Background Meat is a perishable product and during storage, the actions of microorganisms and endogenous enzymes result in chemical compositional changes. Total volatile basic nitrogen (TVB-N) is often used as a biomarker of protein and amine degradation. The broad adoption of TVB-N to interpret meat freshness is somewhat restricted. This is the result of limited or inconsistent knowledge pertaining to the association between TVB-N and other freshness parameters, for beef, sheep/goat meat, pork, chicken and other types of meat, especially when compared to fish. Current meat studies have failed to address the mechanisms between TVB-N generation and production, processing and preservation strategies. Scope and approach Etiology of spoilage and freshness indicators in fresh meat are discussed and various mechanisms contributing to meat spoilage are highlighted. Further, the use and application of TVB-N for understanding the freshness of different meat types has been comprehensively reviewed with the aim of establishing its usefulness as a freshness marker. Key Findings and Conclusions TVB-N increases with meat storage and is aligned with other biomarkers of spoilage (i.e. function of duration, temperature, packaging, etc.). But these increases are not always consistent. There are different recommendations of TVB-N limits for meat freshness. These are primarily for fish and seafood products and therefore inappropriate for other meat types, are species specific, arbitrary, or have an element of ambiguity (e.g. an intermediary ‘stale’ classification between fresh and spoilt states). The selection of TVB-N limits can therefore introduce inaccuracy and subjectivity into the appraisal of meat freshness. Several destructive and non-destructive methods have been used to determine TVB-N, however, their capacity is limited to the differential between spoilt and non-spoilt samples through chemometric classification systems based on predefined TVB-N guidelines. Further reference populations and investigations of red meat types are required.

Total volatile basic nitrogen (TVB-N) and its role in meat spoilage: A review

BackgroundGut microbial metabolites have been implicated as novel risk factors for cardiovascular events and premature death. The strength and consistency of associations between blood concentratio...

Gut Microbiota Metabolites and Risk of Major Adverse Cardiovascular Disease Events and Death: A Systematic Review and Meta-Analysis of Prospective Studies.

AIMS

Systemic levels of trimethylamine N-oxide (TMAO), a pro-atherogenic and pro-thrombotic metabolite produced from gut microbiota metabolism of dietary trimethylamine (TMA)-containing nutrients such as choline or carnitine, predict incident cardiovascular event risks in stable primary and secondary prevention subjects. However, the prognostic value of TMAO in the setting of acute coronary syndromes (ACS) remains unknown.

METHODS AND RESULTS

We investigated the relationship of TMAO levels with incident cardiovascular risks among sequential patients presenting with ACS in two independent cohorts. In the Cleveland Cohort, comprised of sequential subjects (n = 530) presenting to the Emergency Department (ED) with chest pain of suspected cardiac origin, an elevated plasma TMAO level at presentation was independently associated with risk of major adverse cardiac events (MACE, including myocardial infarction, stroke, need for revascularization, or death) over the ensuing 30-day (4th quartile (Q4) adjusted odds ratio (OR) 6.30, 95% confidence interval (CI), 1.89-21.0, P < 0.01) and 6-month (Q4 adjusted OR 5.65, 95%CI, 1.91-16.7; P < 0.01) intervals. TMAO levels were also a significant predictor of the long term (7-year) mortality (Q4 adjusted HR 1.81, 95%CI, 1.04-3.15; P < 0.05). Interestingly, TMAO level at initial presentation predicted risk of incident MACE over the near-term (30 days and 6 months) even among subjects who were initially negative for troponin T (< 0.1 ng/mL) (30 days, Q4 adjusted OR 5.83, 95%CI, 1.79-19.03; P < 0.01). The prognostic value of TMAO was also assessed in an independent multicentre Swiss Cohort of ACS patients (n = 1683) who underwent coronary angiography. Trimethylamine N-oxide again predicted enhanced MACE risk (1-year) (adjusted Q4 hazard ratios: 1.57, 95% CI, 1.03-2.41; P <0.05).

CONCLUSION

Plasma TMAO levels among patients presenting with chest pain predict both near- and long-term risks of incident cardiovascular events, and may thus provide clinical utility in risk stratification among subjects presenting with suspected ACS.

Gut microbiota-dependent trimethylamine N-oxide in acute coronary syndromes: a prognostic marker for incident cardiovascular events beyond traditional risk factors

https://www.kidney-international.org/article/S0085-2538(16)00295-7/pdf

Advanced chronic kidney disease populations have elevated trimethylamine N-oxide levels associated with increased cardiovascular events

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Troy Hamilton

Author Tools

Chat about Author

Papers

Advanced chronic kidney disease populations have elevated trimethylamine N-oxide levels associated with increased cardiovascular events