scholarly journals Mechanisms of Action of Prebiotics and Their Effects on Gastro-Intestinal Disorders in Adults

Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1037 ◽  
Author(s):  
Michele Guarino ◽  
Annamaria Altomare ◽  
Sara Emerenziani ◽  
Claudia Di Rosa ◽  
Mentore Ribolsi ◽  
...  
Keyword(s):  
Resistant Starch ◽  
Short Chain Fatty Acids ◽  
Mechanisms Of Action ◽  
Special Focus ◽  
Dietary Fibers ◽  
Pathological Conditions ◽  
Soybean Oligosaccharides ◽  
Dietary Strategies ◽  
Long Chain ◽  
Emerging Substances

In recent years, research has focused on the use of dietary fibers and prebiotics, since many of these polysaccharides can be metabolized by intestinal microbiota, leading to the production of short-chain fatty acids. The metabolites of prebiotic fermentation also show anti-inflammatory and immunomodulatory capabilities, suggesting an interesting role in the treatment of several pathological conditions. Galacto-oligosaccharide and short- and long-chain fructans (Fructo-oligosaccharides and inulin) are the most studied prebiotics, even if other dietary compounds seem to show the same features. There is an increasing interest in dietary strategies to modulate microbiota. The aim of this review is to explore the mechanisms of action of prebiotics and their effects on the principal gastro-intestinal disorders in adults, with a special focus on Galacto-oligosaccharides, Fructo-oligosaccharides, lactulose and new emerging substances which currently have evidence of prebiotics effects, such as xilooligosaccharides, soybean oligosaccharides, isomaltooligosaccharides, lactobionic acid, resistant starch and polyphenols.

scholarly journals Dietary Fiber Modulates the Fermentation Patterns of Cyanidin-3-O-Glucoside in a Fiber-Type Dependent Manner

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1386
Author(s):  
Zixin Yang ◽  
Ting Huang ◽  
Ping Li ◽  
Jian Ai ◽  
Jiaxin Liu ◽  
...  
Keyword(s):  
Dietary Fiber ◽  
Fiber Type ◽  
Short Chain Fatty Acids ◽  
Dependent Manner ◽  
Dietary Fibers ◽  
Cell Wall Polysaccharides ◽  
Total Carbohydrate ◽  
In Vitro Fermentation ◽  
Gas Volume

The interactions between cell-wall polysaccharides and polyphenols in the gastrointestinal tract have attracted extensive attention. We hypothesized that dietary fiber modulates the fermentation patterns of cyanidin-3-O-glucoside (C3G) in a fiber-type-dependent manner. In the present study, the effects of four dietary fibers (fructose-oligosaccharides, pectin, β-glucan and arabinoxylan) on the modulation of C3G fermentation patterns were investigated through in vitro fermentation inoculated with human feces. The changes in gas volume, pH, total carbohydrate content, metabolites of C3G, antioxidant activity, and microbial community distribution during in vitro fermentation were analyzed. After 24 h of fermentation, the gas volume and total carbohydrate contents of the four dietary-fiber-supplemented groups respectively increased and decreased to varying degrees. The results showed that the C3G metabolites after in vitro fermentation mainly included cyanidin, protocatechuic acid, 2,4,6-trihydroxybenzoic acid, and 2,4,6-trihydroxybenzaldehyde. Supplementation of dietary fibers changed the proportions of C3G metabolites depending on the structures. Dietary fibers increased the production of short-chain fatty acids and the relative abundance of gut microbiota Bifidobacterium and Lactobacillus, thus potentially maintaining colonic health to a certain extent. In conclusion, the used dietary fibers modulate the fermentation patterns of C3G in a fiber-type-dependent manner.

scholarly journals Commensal microbe-derived acetate suppresses NAFLD/NASH development via hepatic FFAR2 signalling in mice

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Ryo Aoki ◽  
Masayoshi Onuki ◽  
Koya Hattori ◽  
Masato Ito ◽  
Takahiro Yamada ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Gut Microbiome ◽  
Resistant Starch ◽  
Short Chain Fatty Acids ◽  
Global Changes ◽  
Severe Liver ◽  
Acetate Production ◽  
Germ Free ◽  
Free Fatty Acid Receptor ◽  
Underlying Mechanisms

Abstract Background Non-alcoholic liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome, and it can progress to non-alcoholic steatohepatitis (NASH). Alterations in the gut microbiome have been implicated in the development of NAFLD/NASH, although the underlying mechanisms remain unclear. Results We found that the consumption of the prebiotic inulin markedly ameliorated the phenotype of NAFLD/NASH, including hepatic steatosis and fibrosis, in mice. Inulin consumption resulted in global changes in the gut microbiome, including concomitant enrichment of the genera Bacteroides and Blautia, and increased concentrations of short-chain fatty acids, particularly acetate, in the gut lumen and portal blood. The consumption of acetate-releasing resistant starch protected against NAFLD development. Colonisation by Bacteroides acidifaciens and Blautia producta in germ-free mice resulted in synergetic effects on acetate production from inulin. Furthermore, the absence of free fatty acid receptor 2 (FFAR2), an acetate receptor, abolished the protective effect of inulin, as indicated by the more severe liver hypertrophy, hypercholesterolaemia and inflammation. These effects can be attributed to an exacerbation of insulin resistance in the liver, but not in muscle or adipose tissue. Conclusion These findings demonstrated that the commensal microbiome–acetate–FFAR2 molecular circuit improves insulin sensitivity in the liver and prevents the development of NAFLD/NASH.

scholarly journals DIETARY FIBERS: ANALYSIS METHODS

2018 ◽  
Vol 5 (3) ◽  
pp. 174-179
Author(s):  
Karen Carvalho Ferreira ◽  
Juliana Aparecida Correia Bento ◽  
Lázaro Sátiro De Jesus ◽  
Priscila Zaczuk Bassinelo
Keyword(s):  
Dietary Fiber ◽  
Resistant Starch ◽  
Analysis Time ◽  
Dietary Fibers ◽  
Waste Generation ◽  
Analysis Methods ◽  
Aoac Official ◽  
Innovative Techniques

Dietary fiber (DF) intake is associated with a number of benefits and these effects depend not only on intake as well as its composition. The DF includes polysaccharides such as cellulose, hemicellulose, pectins, gums, oligosaccharides and lignin, and can be divided into soluble and insoluble. The concept of DF was expanded to include resistant starch, inulin and fructo-oligosaccharides. The determination of DF costly and time depends on methods that have been modified for this new concept. The AOAC Official methods of determining all components present in a DF, without specific methods for each component. Studies show innovative techniques to ensure a shorter analysis time, less waste generation by the use of reagents and more convenience in the analysis.

scholarly journals Long-chain polyunsaturated fatty acids: Selected mechanisms of action on bone

2010 ◽  
Vol 49 (4) ◽  
pp. 438-449 ◽  
Author(s):  
M.C. Kruger ◽  
M. Coetzee ◽  
M. Haag ◽  
H. Weiler
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Mechanisms Of Action ◽  
Long Chain

Polyphenols: Novel Signaling Pathways

2018 ◽  
Vol 24 (2) ◽  
pp. 158-170 ◽  
Author(s):  
Marie-Louise Ricketts ◽  
Bradley S. Ferguson
Keyword(s):  
Risk Factors ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Density Lipoprotein ◽  
Mechanisms Of Action ◽  
Metabolic Effects ◽  
Special Focus ◽  
In Vivo Models ◽  
Alcoholic Fatty Liver ◽  
The Metabolic Syndrome

Background: Cardiovascular disease (CVD) is currently the leading cause of death globally. The metabolic syndrome (MetS), a clustering of risk factors including hypertension, hyperglycemia, elevated low-density lipoprotein (LDL) cholesterol, reduced high-density lipoprotein (HDL) cholesterol and increased visceral adiposity, is a significant risk factor for the development of CVD. Non-alcoholic fatty liver disease (NAFLD), often referred to as the hepatic manifestation of MetS, is a constellation of progressive liver disorders closely linked to obesity, diabetes, and insulin resistance. NAFLD initially presents as relatively benign, non-progressive hepatic steatosis, but it may, in certain individuals, progress to nonalcoholic steatohepatitis, fibrosis, cirrhosis, or hepatocellular carcinoma. Currently, there are no validated treatments for NAFLD. Polyphenols are important bioactive dietary compounds and may represent a natural complementary and integrative therapy for the treatment of CVDassociated risk factors, including elevated serum cholesterol and triglyceride levels, as well as NAFLD. Understanding their molecular mechanisms of action is important in the design of future human intervention studies. Methods: Several studies utilizing in vitro and in vivo models have helped to identify underlying molecular mechanisms of action of polyphenols. Results: This review will highlight recent advances regarding the molecular actions of dietary procyanidins, with a special focus on those originating from procyanidin-rich grape seed extracts, with a focus on the signaling pathways utilized to exert beneficial metabolic effects. Conclusion: Modulation of nuclear receptor activity and histone deacetylase inhibition has been identified as underlying mechanisms contributing to procyanidin-mediated amelioration of dyslipidemia and steatosis.

scholarly journals Modulation of Autophagy for Controlling Immunity

Cells ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 138 ◽  
Author(s):  
Young Jin Jang ◽  
Jae Hwan Kim ◽  
Sanguine Byun
Keyword(s):  
Immune Responses ◽  
Therapeutic Potential ◽  
Inflammatory Diseases ◽  
Mechanisms Of Action ◽  
Innate And Adaptive Immunity ◽  
Pathological Conditions ◽  
Physiological Homeostasis ◽  
Autophagy Pathway ◽  
Key Steps ◽  
Additional Role

Autophagy is an essential process that maintains physiological homeostasis by promoting the transfer of cytoplasmic constituents to autophagolysosomes for degradation. In immune cells, the autophagy pathway plays an additional role in facilitating proper immunological functions. Specifically, the autophagy pathway can participate in controlling key steps in innate and adaptive immunity. Accordingly, alterations in autophagy have been linked to inflammatory diseases and defective immune responses against pathogens. In this review, we discuss the various roles of autophagy signaling in coordinating immune responses and how these activities are connected to pathological conditions. We highlight the therapeutic potential of autophagy modulators that can impact immune responses and the mechanisms of action responsible.

scholarly journals Changes in the Gut Microbiome Contribute to Changes in Tissue Gene Expression in Rats Fed Prebiotic Dietary Fibers (P15-022-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Breann Abernathy ◽  
Ran Blekhman ◽  
Tonya Schoenfuss ◽  
Daniel Gallaher
Keyword(s):  
Gene Expression ◽  
Gut Microbiome ◽  
Cholesterol Synthesis ◽  
Health Benefits ◽  
Short Chain Fatty Acids ◽  
Receptor Expression ◽  
Liver Cholesterol ◽  
Dietary Fibers ◽  
Pathway Gene ◽  
Liver Tissues

Abstract Objectives We investigated the intersection between the gut microbiome and gene expression of colon and liver tissues in rats, using prebiotic dietary fibers to modulate the gut microbiome and elicit health benefits to the host. Methods Male Wistar rats were fed normal fat (NF) or high fat (HF, 51% fat by kcal) diets containing various fibers (6% fiber + 3% cellulose, by weight); including cellulose (NFC and HFC, non-fermentable), polylactose (HFPL, a novel prebiotic), and polydextrose (HFPD, an established prebiotic). After 10 weeks, tissues were harvested. Transcriptome analysis was performed by RNA sequencing of colon and liver tissues, and cecal contents were utilized for 16S microbiome sequencing. Analyses were conducted in R using DESeq2, DADA2, and phyloseq. Results Analysis of the gut microbiome revealed an increased abundance of probiotic genera, Bifidobacterium and Lactobacillus, in HFPL fed animals when compared to all other groups. These species are galactose fermenters which synthesize short chain fatty acids (SCFAs). This increased taxonomical abundance correlated with an increased FFar3 (SCFA receptor) expression in the colon. This suggests increased FFar3 signaling, leading to increased energy expenditure and GLP-1 and PYY secretion. Additionally, HFPL and HFPD groups had a decreased Firmicutes: Bacteroidetes ratio, which is associated with reduced adiposity due to the Bacteroidetes phylum being poor carbohydrate metabolizers, resulting in reduced energy uptake, yet increased SCFA synthesis. Bacteriodetes are also able to survive in SCFA and bile acid rich environments and are involved in the recycling of bile acids which negatively regulates cholesterol synthesis. This corresponds to reduced liver cholesterol and cholesterol synthesis pathway expression in the HFPL group. Further, liver gene expression revealed reduced lipid synthesis and increased lipid oxidation pathway gene expression in the HFPL group, corresponding to the reduction in fatty liver found in this group. Conclusions Prebiotic dietary fibers elicit changes in the gut microbiome and gene expression in liver and colon. Changes in gene expression correlated with the abundance of beneficial gut bacteria, providing a connection between the gut microbiome and health benefits to the host. Funding Sources Midwest Dairy Association. Supporting Tables, Images and/or Graphs

Gut–brain axis: Physiology and pathology

2018 ◽  
Author(s):  
Carla Petrella ◽  
Giuseppe Nisticò ◽  
Robert Nisticò
Keyword(s):  
Mental Health ◽  
Clinical Evidence ◽  
Brain Plasticity ◽  
Large Body ◽  
Gastrointestinal Function ◽  
Gut Flora ◽  
Intestinal Homeostasis ◽  
Pathological Conditions ◽  
Dietary Strategies

A large body of research has shown the presence of a complex pathway of communication between gut and brain. It is now recognized that, through this pathway, microbiota can influence intestinal homeostasis and modulate brain plasticity in normal and pathological conditions. This chapter provides an overview of preclinical and clinical evidence supporting the possible mechanisms whereby microbiota can influence gastrointestinal function and stress-related behaviour. Since normalization of gut flora can prevent changes in behaviour, the authors further postulate that the gut–brain axis might represent a possible target for pharmacological and dietary strategies aimed at improving intestinal and mental health.

scholarly journals Extracellular Vesicles as Biological Shuttles for Targeted Therapies

2019 ◽  
Vol 20 (8) ◽  
pp. 1848 ◽  
Author(s):  
Stefania Raimondo ◽  
Gianluca Giavaresi ◽  
Aurelio Lorico ◽  
Riccardo Alessandro
Keyword(s):  
Extracellular Vesicles ◽  
Therapeutic Agents ◽  
Bioactive Molecules ◽  
Target Cells ◽  
Special Focus ◽  
Pathological Conditions ◽  
Critical Issues ◽  
Membrane Bound ◽  
And Function ◽  
Potential Use

The development of effective nanosystems for drug delivery represents a key challenge for the improvement of most current anticancer therapies. Recent progress in the understanding of structure and function of extracellular vesicles (EVs)—specialized membrane-bound nanocarriers for intercellular communication—suggests that they might also serve as optimal delivery systems of therapeutics. In addition to carrying proteins, lipids, DNA and different forms of RNAs, EVs can be engineered to deliver specific bioactive molecules to target cells. Exploitation of their molecular composition and physical properties, together with improvement in bio-techniques to modify their content are critical issues to target them to specific cells/tissues/organs. Here, we will discuss the current developments in the field of animal and plant-derived EVs toward their potential use for delivery of therapeutic agents in different pathological conditions, with a special focus on cancer.

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