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Nutrients Dec 2021Many articles and manuscripts focusing on the structure, function, mechanism of action, and effects of β-glucan have been published recently [...].
Many articles and manuscripts focusing on the structure, function, mechanism of action, and effects of β-glucan have been published recently [...].
Topics: Dietary Fiber; Food Analysis; Health Promotion; Humans; Nutritive Value; beta-Glucans
PubMed: 35010971
DOI: 10.3390/nu14010096 -
Medicina (Kaunas, Lithuania) 2007Beta-glucans are naturally occurring polysaccharides. These glucose polymers are constituents of the cell wall of certain pathogenic bacteria and fungi. The healing and... (Review)
Review
Beta-glucans are naturally occurring polysaccharides. These glucose polymers are constituents of the cell wall of certain pathogenic bacteria and fungi. The healing and immunostimulating properties of mushrooms have been known for thousands of years in the Eastern countries. These mushrooms contain biologically active polysaccharides that mostly belong to group of beta-glucans. These substances increase host immune defense by activating complement system, enhancing macrophages and natural killer cell function. The induction of cellular responses by mushroom and other beta-glucans is likely to involve their specific interaction with several cell surface receptors, as complement receptor 3 (CR3; CD11b/CD18), lactosylceramide, selected scavenger receptors, and dectin-1 (betaGR). beta-Glucans also show anticarcinogenic activity. They can prevent oncogenesis due to the protective effect against potent genotoxic carcinogens. As immunostimulating agent, which acts through the activation of macrophages and NK cell cytotoxicity, beta-glucan can inhibit tumor growth in promotion stage too. Anti-angiogenesis can be one of the pathways through which beta-glucans can reduce tumor proliferation, prevent tumor metastasis. beta-Glucan as adjuvant to cancer chemotherapy and radiotherapy demonstrated the positive role in the restoration of hematopiesis following by bone marrow injury. Immunotherapy using monoclonal antibodies is a novel strategy of cancer treatment. These antibodies activate complement system and opsonize tumor cells with iC3b fragment. In contrast to microorganisms, tumor cells, as well as other host cells, lack beta-glucan as a surface component and cannot trigger complement receptor 3-dependent cellular cytotoxicity and initiate tumor-killing activity. This mechanism could be induced in the presence of beta-glucans.
Topics: Adjuvants, Immunologic; Adult; Agaricales; Angiogenesis Inhibitors; Animals; Antibodies, Monoclonal; Humans; Immune System; Immunity; Immunotherapy; Mice; Middle Aged; Neoplasms; Randomized Controlled Trials as Topic; Receptors, Complement; beta-Glucans
PubMed: 17895634
DOI: No ID Found -
Molecular Nutrition & Food Research Jan 2021The innate immune system responds in a rapid and non-specific manner against immunologic threats; inflammation is part of this response. This is followed by a slower but... (Review)
Review
The innate immune system responds in a rapid and non-specific manner against immunologic threats; inflammation is part of this response. This is followed by a slower but targeted and specific response termed the adaptive or acquired immune response. There is emerging evidence that dietary components, including yeast-derived β-glucans, can aid host defense against pathogens by modulating inflammatory and antimicrobial activity of neutrophils and macrophages. Innate immune training refers to a newly recognized phenomenon wherein compounds may "train" innate immune cells, such that monocyte and macrophage precursor biology is altered to mount a more effective immunological response. Although various human studies have been carried out, much uncertainty still exists and further studies are required to fully elucidate the relationship between β-glucan supplementation and human immune function. This review offers an up-to-date report on yeast-derived β-glucans as immunomodulators, including a brief overview of the current paradigm regarding the interaction of β-glucans with the immune system. The recent pre-clinical work that has partly decrypted mode of action and the newest evidence from human trials are also reviewed. According to pre-clinical studies, β-1,3/1,6-glucan derived from baker's yeast may offer increased immuno-surveillance, although the human evidence is weaker than that gained from pre-clinical studies.
Topics: Age Factors; Animals; Athletes; Glucans; Host-Pathogen Interactions; Humans; Immunity, Innate; Immunologic Factors; Lectins, C-Type; Respiratory Tract Infections; beta-Glucans
PubMed: 32223047
DOI: 10.1002/mnfr.201901071 -
Cell Reports May 2020β-glucan is a potent inducer of epigenetic and functional reprogramming of innate immune cells, a process called "trained immunity," resulting in an enhanced host...
β-glucan is a potent inducer of epigenetic and functional reprogramming of innate immune cells, a process called "trained immunity," resulting in an enhanced host response against secondary infections. We investigate whether β-glucan exposure confers protection against pulmonary Mycobacterium tuberculosis (Mtb) infection. β-glucan induces trained immunity via histone modifications at gene promoters in human monocytes, which is accompanied by the enhanced production of proinflammatory cytokines upon secondary Mtb challenge and inhibition of Mtb growth. Mice treated with β-glucan are significantly protected against pulmonary Mtb infection, which is associated with the expansion of hematopoietic stem and progenitor cells in the bone marrow and increased myelopoiesis. The protective signature of β-glucan is mediated via IL-1 signaling, as β-glucan shows no protection in mice lacking a functional IL-1 receptor (IL1R). The administration of β-glucan may be used as a novel strategy in the treatment of mycobacterial infections and possibly as an adjuvant to improve anti-tuberculosis vaccines.
Topics: Animals; Humans; Immunity; Interleukin-1; Mice; Mycobacterium tuberculosis; Signal Transduction; beta-Glucans
PubMed: 32433977
DOI: 10.1016/j.celrep.2020.107634 -
The Journal of Biological Chemistry Jun 2022Not all starches in the human diet are created equal: "resistant starches" are consolidated aggregates of the α-glucan polysaccharides amylose and amylopectin, which...
Not all starches in the human diet are created equal: "resistant starches" are consolidated aggregates of the α-glucan polysaccharides amylose and amylopectin, which escape digestion by salivary and pancreatic amylases. Upon reaching the large intestine, resistant starches become fodder for members of the human gut microbiota, impacting the metabolism of both the symbionts and the host. In a recent study, Koropatkin et al. provided new molecular insight into how a keystone bacterium in the human gut microbiota adheres to resistant starches as a prelude to their breakdown and fermentation.
Topics: Amylopectin; Amylose; Gastrointestinal Microbiome; Glucans; Humans; Starch; alpha-Amylases
PubMed: 35597281
DOI: 10.1016/j.jbc.2022.102049 -
International Journal of Molecular... Jun 2019In recent decades, various polysaccharides isolated from algae, mushrooms, yeast, and higher plants have attracted serious attention in the area of nutrition and... (Review)
Review
In recent decades, various polysaccharides isolated from algae, mushrooms, yeast, and higher plants have attracted serious attention in the area of nutrition and medicine. The reasons include their low toxicity, rare negative side effects, relatively low price, and broad spectrum of therapeutic actions. The two most and best-studied polysaccharides are mannan and glucan. This review focused on their biological properties.
Topics: Animals; Antineoplastic Agents; Fungal Polysaccharides; Glucans; Humans; Hypolipidemic Agents; Immunologic Factors; Macrophages; Mannans
PubMed: 31261851
DOI: 10.3390/ijms20133189 -
Molecules (Basel, Switzerland) Apr 2021Although the anti-tumor and anti-infective properties of β-glucans have been well-discussed, their role in bone metabolism has not been reviewed so far. This review... (Review)
Review
Although the anti-tumor and anti-infective properties of β-glucans have been well-discussed, their role in bone metabolism has not been reviewed so far. This review discusses the biological effects of β-glucans on bone metabolisms, especially on bone-resorbing osteoclasts, which are differentiated from hematopoietic precursors. Multiple immunoreceptors that can recognize β-glucans were reported to be expressed in osteoclast precursors. Coordinated co-stimulatory signals mediated by these immunoreceptors are important for the regulation of osteoclastogenesis and bone remodeling. Curdlan from the bacterium negatively regulates osteoclast differentiation in vitro by affecting both the osteoclast precursors and osteoclast-supporting cells. We also showed that laminarin, lichenan, and glucan from baker's yeast, as well as β-1,3-glucan from inhibit the osteoclast formation in bone marrow cells. Consistent with these findings, systemic and local administration of β-glucan derived from and suppressed bone resorption in vivo. However, zymosan derived from stimulated the bone resorption activity and is widely used to induce arthritis in animal models. Additional research concerning the relationship between the molecular structure of β-glucan and its effect on osteoclastic bone resorption will be beneficial for the development of novel treatment strategies for bone-related diseases.
Topics: Animals; Bone Regeneration; Bone Resorption; Bone and Bones; Cartilage; Cell Differentiation; Glucans; Humans; Immunomodulation; Osteoclasts; Osteogenesis; Receptors, Immunologic
PubMed: 33915775
DOI: 10.3390/molecules26071982 -
Marine Drugs Nov 2021spp. are generally found in aquatic environments, although they have also been isolated from both fresh and processed food. These Gram-negative, rod-shaped bacteria are... (Review)
Review
spp. are generally found in aquatic environments, although they have also been isolated from both fresh and processed food. These Gram-negative, rod-shaped bacteria are mostly infective to poikilothermic animals, although they are also considered opportunistic pathogens of both aquatic and terrestrial homeotherms, and some species have been associated with gastrointestinal and extraintestinal septicemic infections in humans. Among the different pathogenic factors associated with virulence, several cell-surface glucans have been shown to contribute to colonization and survival of pathogenic strains, in different hosts. Lipopolysaccharide (LPS), capsule and α-glucan structures, for instance, have been shown to play important roles in bacterial-host interactions related to pathogenesis, such as adherence, biofilm formation, or immune evasion. In addition, glycosylation of both polar and lateral flagella has been shown to be mandatory for flagella production and motility in different strains, and has also been associated with increased bacterial adhesion, biofilm formation, and induction of the host proinflammatory response. The main aspects of these structures are covered in this review.
Topics: Aeromonas; Animals; Aquatic Organisms; Bacterial Adhesion; Glucans; Humans
PubMed: 34822520
DOI: 10.3390/md19110649 -
Carbohydrate Research Oct 2021Bottom-up synthesis of β-glucans such as callose, fungal β-(1,3)(1,6)-glucan and cellulose, can create the defined compounds that are needed to perform fundamental... (Review)
Review
Bottom-up synthesis of β-glucans such as callose, fungal β-(1,3)(1,6)-glucan and cellulose, can create the defined compounds that are needed to perform fundamental studies on glucan properties and develop applications. With the importance of β-glucans and cellulose in high-profile fields such as nutrition, renewables-based biotechnology and materials science, the enzymatic synthesis of such relevant carbohydrates and their derivatives has attracted much attention. Here we review recent developments in enzymatic synthesis of β-glucans and cellulose, with a focus on progress made over the last five years. We cover the different types of biocatalysts employed, their incorporation in cascades, the exploitation of enzyme promiscuity and their engineering, and reaction conditions affecting the production as well as in situ self-assembly of (non)functionalised glucans. The recent achievements in the application of glycosyl transferases and β-1,4- and β-1,3-glucan phosphorylases demonstrate the high potential and versatility of these biocatalysts in glucan synthesis in both industrial and academic contexts.
Topics: Cellulose; Phosphorylases; beta-Glucans
PubMed: 34392134
DOI: 10.1016/j.carres.2021.108411 -
Marine Drugs Oct 2021During the processes of primary and secondary endosymbiosis, different microalgae evolved to synthesis different storage polysaccharides. In stramenopiles, the main... (Review)
Review
During the processes of primary and secondary endosymbiosis, different microalgae evolved to synthesis different storage polysaccharides. In stramenopiles, the main storage polysaccharides are β-1,3-glucan, or laminarin, in vacuoles. Currently, laminarin is gaining considerable attention due to its application in the food, cosmetic and pharmaceuticals industries, and also its importance in global biogeochemical cycles (especially in the ocean carbon cycle). In this review, the structures, composition, contents, and bioactivity of laminarin were summarized in different algae. It was shown that the general features of laminarin are species-dependence. Furthermore, the proposed biosynthesis and catabolism pathways of laminarin, functions of key genes, and diel regulation of laminarin were also depicted and comprehensively discussed for the first time. However, the complete pathways, functions of genes, and diel regulatory mechanisms of laminarin require more biomolecular studies. This review provides more useful information and identifies the knowledge gap regarding the future studies of laminarin and its applications.
Topics: Animals; Aquatic Organisms; Biological Products; Glucans; Polysaccharides; Stramenopiles; Structure-Activity Relationship
PubMed: 34677475
DOI: 10.3390/md19100576