Polysaccharide fraction of Agaricus brasiliensis avoids tumor-induced IL-10 production and changes the microenvironment of subcutaneous Ehrlich adenocarcinoma

Fermented rye with Agaricus subrufescens and mannan-rich hydrolysate based feed additive to modulate post-weaning piglet immune response

BACKGROUND

The process of weaning in piglets is often associated with an increased inflammation response in the intestine and compromised intestinal integrity and morphology, favoring a delay in intestinal maturation and a predisposal to diseases. Research has shown the potential of different nutritional strategies to reduce the production of pro-inflammatory cytokines, with the main goal to manipulate health and performance of pigs. Promising examples of nutritional strategies are fungal fermented products and their derivatives which are described to contain several compounds that may play a role in gastrointestinal health and pathogenic bacteria control. Products from Agaricus subrufescens mushroom are reported to contain prophylactic and therapeutic properties including antimicrobial and immunomodulatory properties.

RESULTS

This study analysed the post-weaning immune status in intestinal tissue and blood of piglets, with the objective to evaluate the gastrointestinal health and immune modulation response induced by a blend of mannan-rich hydrolyzed copra meal and fermented rye with A. subrufescens. Intestinal histomorphology demonstrated a villus height reduction in jejunum and increase in ileum on day 15, while increased villous height in jejunum and ileum on day 30. The results showed that in post-weaning piglets, the feed additive stimulates an immunomodulation effect most evident at 15 days post-weaning, with significant lower expression of cytokines Interferon (IFN) γ, Interleukin (IL) 1α, IL-1β, IL-6, IL-8, IL-10 and Transforming Growth Factor (TGF) β in jejunum, accompanied with an increase in peripheral blood mononuclear cells (PBMC) cytokine gene expression of IL-1β, IL-6, IL-8, IL-10, IL-12p35 (IL-12α), IL-12p40 (IL-12β), Tumor Necrosis Factor (TNF) α, IFN-α, and TGF-β. In piglets fed the feed additive, the quantity of Immunoglobulin (Ig) A producing cells in jejunum, ileum was reduced on day 15 and 30 post-weaning, and on day 30 and 45 post-weaning in colon tissue. Natural Killer (NK) cells count in blood were increased on day 15 post-weaning in the piglets fed the feed additive.

CONCLUSION

This study implies the potential of the blend including mannan-rich hydrolyzed copra meal and fermented rye with A. subrufescens on immune modulation in the intestine of post-weaning piglets.

Edible fungal polysaccharides, the gut microbiota, and host health

The plasticity of the gut microbiota (GM) creates an opportunity to reshape the biological output of gut microbes by manipulating external factors. It is well known that edible fungal polysaccharides (EFPs) can reach the distal intestine and be assimilated to reshape the GM. The GM has unique devices that utilize various EFPs and produce oligosaccharides, which can selectively promote the growth of beneficial bacteria and are fermented into short-chain fatty acids that interact closely with intestinal cells. Here we review EFPs-based interventions for the GM, particularly the key microorganisms, functions, and metabolites. In addition, we discuss the bi-directional causality between GM imbalance and diseases, and the beneficial effects of EFPs on host health via GM. This review can offer a valuable reference for the design of edible fungal polysaccharide- or oligosaccharide-based nutrition interventions or drug development for maintaining human health by targeted regulation of the GM.

Treasures from the forest: Evaluation of mushroom extracts as anti-cancer agents

Mushrooms provide a reliable source of bioactive compounds and have numerous nutritional values, which is one of the reasons why they are widely used for culinary purposes. They may also be a remedy for several medical conditions, including cancer diseases. Given the constantly increasing number of cancer incidents, the great anticancer potential of mushrooms has unsurprisingly become an object of interest to researchers. Therefore, this review aimed to collect and summarize all the available scientific data on the anti-cancer activity of mushroom extracts. Our research showed that mushroom extracts from 92 species, prepared using 12 different solvents, could reduce the viability of 38 various cancers. Additionally, we evaluated different experimental models: in vitro (cell model), in vivo (mice and rat model, case studies and randomized controlled trials), and in silico. Breast cancer proved to be sensitive to the highest number of mushroom extracts. The curative mechanisms of the studied mushrooms consisted in: inhibition of cancer cell proliferation, unregulated proportion of cells in cell cycle phases, induction of autophagy and phagocytosis, improved response of the immune system, and induction of apoptotic death of cells via upregulation of pro-apoptotic factors and downregulation of anti-apoptotic genes. The processes mainly involved the expression of caspases -3, -8, -9, AKT, p27, p53, BAX, and BCL2. The quoted results could lead to the classification of mushrooms as nutraceuticals used to prevent a variety of disorders or to support treatment of cancer diseases.

Polysaccharides and extracts from Agaricus brasiliensis Murill - A comprehensive review

Edible mushrooms have been increasingly introduced into the human diet, which has driven research into their functional properties. Thus, Agaricus brasiliensis Murill or Agaricus blazei Murill (ABM) is a species native to the Brazilian biome, whose fruiting body has been used not only for dietary purposes, but also in the development of functional foods or as source of molecules of pharmacological interest. The bioactivity of ABM has been related to the presence of polysaccharides, although the contribution of other metabolites cannot be discharged. This work describes the polysaccharides isolation methodology and preparation of the extracts of ABM and their biological activities. Furthermore, it presents a general outline of its characterizations regarding composition, chemical structure and properties in solution. The ABM and its chemical constituents exhibit several biological activities that support their potential use for prevention or treatment of diseases with inflammatory background, such as cancer, diabetes and atherosclerosis. The mechanism of action of the extracts and polysaccharides from ABM is mainly related to a modulation of immune system response or reduction of inflammatory response. This review shows that the ABM has great potential in the pharmaceutical, biotechnological and food sectors that deserves additional research using standardized products.

Antitumor, Anti-Inflammatory and Antiallergic Effects of Agaricus blazei Mushroom Extract and the Related Medicinal Basidiomycetes Mushrooms, Hericium erinaceus and Grifola frondosa: A Review of Preclinical and Clinical Studies

Since the 1980s, medicinal effects have been documented in scientific studies with the related Basidiomycota mushrooms Agaricus blazei Murill (AbM), Hericium erinaceus (HE) and Grifola frondosa (GF) from Brazilian and Eastern traditional medicine. Special focus has been on their antitumor effects, but the mushrooms' anti-inflammatory and antiallergic properties have also been investigated. The antitumor mechanisms were either direct tumor attack, e.g., apoptosis and metastatic suppression, or indirect defense, e.g., inhibited tumor neovascularization and T helper cell (Th) 1 immune response. The anti-inflammatory mechanisms were a reduction in proinflammatory cytokines, oxidative stress and changed gut microbiota, and the antiallergic mechanism was amelioration of a skewed Th1/Th2 balance. Since a predominant Th2 milieu is also found in cancer, which quite often is caused by a local chronic inflammation, the three conditions-tumor, inflammation and allergy-seem to be linked. Further mechanisms for HE were increased nerve and beneficial gut microbiota growth, and oxidative stress regulation. The medicinal mushrooms AbM, HE and GF appear to be safe, and can, in fact, increase longevity in animal models, possibly due to reduced tumorigenesis and oxidation. This article reviews preclinical and clinical findings with these mushrooms and the mechanisms behind them.

Agaricus brasiliensis polysaccharides stimulate human monocytes to capture Candida albicans, express toll-like receptors 2 and 4, and produce pro-inflammatory cytokines

Background

Agaricus brasiliensis is a medicinal mushroom with immunomodulatory and antitumor activities attributed to the β-glucans presented in the polysaccharide fraction of its fruiting body. Since β-glucans enhance cellular immunoresponsiveness, in this study we aimed to evaluate the effect of an acid-treated polysaccharide-rich fraction (ATF) of A. brasiliensis on the ability of human monocytes to adhere/phagocyte C. albicans yeast cells, their expression of pattern recognition receptors and their ability to produce cytokines.

Methods

Adhesion/phagocytosis of FITC-labeled C. albicans was evaluated by flow cytometry. Cells were incubated with specific fluorochrome-labeled antibodies for TLR2 and 4, βGR and MR and also evaluated by flow cytometry. Monocytes were cultured with ATF, and culture supernatants were collected for analysis of in vitro cytokine production by ELISA (TNF-α, IL-1β, IL-12 and IL-10).

Results

ATF significantly increased the adherence/phagocytosis of C. albicans by monocytes and this was associated with enhanced expression of TLR2 and TLR4, while no effect was observed on βGR or MR. Moreover, expression of TLR4 and TLR2 was associated with higher levels of in vitro production of TNF-α and IL-1, respectively. Production of IL-10 was also increased by ATF treatment, but we found no association between its production and the expression of Toll-like receptors.

Conclusion

Our results provided us with evidence that A. brasiliensis polysaccharides affect human monocytes probably through the modulation of Toll-like receptors.

Tumor Microenvironment as a New Target for Tumor Immunotherapy of Polysaccharides

Many researches show that polysaccharides derived from fungi and plants have strong pharmacological activities such as enhancing the organism immune and anti-tumor function, and have few toxic and side effects. So the polysaccharides show a wide application prospect in the prevention and therapy of tumor. The tumor microenvironment consists of tumor cells and tumor cells' surrounding environment. The tumor microenvironment not only plays a key role in the development of tumor, but also is a potential treasure for searching new ways to treat tumor. In this review, we summarized polysaccharides' regulation effects on tumor microenvironment progression and tried to give a new theoretical basis for the exploitation of polysaccharides with anti-tumor activity.

Anticancer polysaccharides from natural resources: a review of recent research

Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. However, almost all of the chemotherapy drugs currently on the market cause serious side effects. Fortunately, several previous studies have shown that some non-toxic biological macromolecules, including polysaccharides and polysaccharide-protein complexes, possess anti-cancer activities or can increase the efficacy of conventional chemotherapy drugs. Based on these encouraging observations, a great deal of effort has been focused on discovering anti-cancer polysaccharides and complexes for the development of effective therapeutics for various human cancers. This review focuses on the advancements in the anti-cancer efficacy of various natural polysaccharides and polysaccharide complexes in the past 5 years. Most polysaccharides were tested using model systems, while several involved clinical trials.

Agaricus subrufescens: A review

Medicinal mushrooms have currently become a hot issue due to their various therapeutic properties. Of these, Agaricus subrufescens, also known as the "almond mushroom", has long been valued by many societies (i.e., Brazil, China, France, and USA). Since its discovery in 1893, this mushroom has been cultivated throughout the world, especially in Brazil where several strains of A. subrufescens have been developed and used as health food and alternative medicine. This article presents up-to-date information on this mushroom including its taxonomy and health promoting benefits. Medicinal properties of A. subrufescens are emphasized in several studies which are reviewed here. In addition, safety issues concerning the use of this fungus will be discussed.

Does the Agaricus blazei Murill mushroom have properties that affect the immune system? An integrative review

There has been a significant increase in the use of mushrooms for therapeutic and medicinal purposes, in particular, use of the species Agaricus blazei Murrill, a basidiomycota of Brazilian origin. The objective of this study was to identify scientific evidence regarding the influence of A. blazei Murrill on the immune system. We undertook an integrative review of indexed publications published between 2000 and 2009, using the following question as a guideline: "What evidence can be found in the literature regarding the influence of A. blazei Murrill on the immune system?" Fourteen studies verified that there is in vitro and in vivo research demonstrating this mushroom's influence on the immune system. All research was characterized as evidence level 7 (preclinical study [animals/in vitro]). The research shows that A. blazei Murrill functions through bioactive compounds via mechanisms that are not yet entirely clear, although it has been shown that they promote action on the innate and adaptive immunological response, activation of the complement system, and synthesis of pro- and anti-inflammatory cytokines and even aid in diapedesis. Despite broad scientific evidence demonstrating relevant immunomodulatory properties of A. blazei Murrill, randomized clinical trials with human subjects are still needed in order for the mushroom to be put into clinical practice.

Influence of drying methods over in vitro antitumoral effects of exopolysaccharides produced by Agaricus blazei LPB 03 on submerged fermentation

Agaricus blazei is a mushroom that belongs to the Brazilian biodiversity and is considered as an important producer of bioactive compounds beneficial to human health. Studies have demonstrated that these compounds present immuno-modulatory, antioxidant and antitumor properties. In order to compare the most used method for fungal polysaccharide drying, lyophilization with other industrial-scale methods, the aim of this work was to submit A. blazei LPB 03 polysaccharide extracts to vaucum, spray and freeze drying, and evaluate the maintenance of its antitumoral effects in vitro. Exopolysaccharides produced by A. blazei LPB 03 on submerged fermentation were extracted with ethanol and submitted to drying processes. The efficiency represents the water content that was removed during the drying process. The resultant dried products showed water content around 3% and water activity less than 0.380, preventing therefore the growth of microorganisms and reactions of chemical degradation. Exopolysaccharide extracts dried by vacuum and spray dryer did not showed any significant cytotoxic effect on cell viability of Wistar mice macrophages. Content of total sugars and protein decrease after drying, nevertheless, 20 mg/ml of exopolysaccharides dried by spray dryer reached 33% of inhibition rate over Ehrlich tumor cells in vitro.

Effects of Agaricus brasiliensis mushroom in Walker-256 tumor-bearing rats

Agaricus brasiliensis is a mushroom native to São Paulo State, Brazil, that is studied for its medicinal proprieties. This work aimed to investigate the antitumoral activity of A. brasiliensis extracts and pure powdered basidiocarp preparation using Walker-256 (W256) tumor-bearing rats, a model for cancer-related cachexia studies. The rats were treated for 14 days by gavage (136 mg/kg) and at the end of the experiment tumors were collected to calculate mass and volume. Blood was collected for determination of plasma glucose, albumin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Hepatic and tumor enzymes indicating oxidative stress were also evaluated. The results showed that all 4 treatments (pure powdered basidiocarp and aqueous, acid, and alkaline extracts) significantly reduced tumor size and promoted gain in body weight. Plasmatic analysis showed a reduction in AST level and increased glycemia in the treated rats. Pure basidiocarp preparations improved the liver catalase and superoxide dismutase activity, but did not change the glutathione S-transferase activity. The data collected from the W256 tumor-bearing rats revealed the beneficial effects of A. brasiliensis in tumor treatment, mainly related to cachexia. The benefits can be partly related to antioxidant activity and to reduction of weight loss and tumor growth.

Oral administration of an Enoki mushroom protein FVE activates innate and adaptive immunity and induces anti-tumor activity against murine hepatocellular carcinoma

FVE is a documented immunomodulatory protein purified from Enoki mushroom (Flammulina velutipes) and known as an activator for human T lymphocytes. This present study was aimed to investigate the anti-tumor effect and the related mechanisms of oral administration of FVE using a murine hepatoma model. Oral administration of FVE (10mg/kg) significantly increased the life span and inhibited the tumor size of BNL 1MEA.7R.1 (BNL) hepatoma-bearing mice. Tumor-bearing mice receiving oral FVE treatment had the highest tumoricidal capacity of peritoneal macrophages and tumor-specific splenocytes against BNL hepatoma cells. In addition, in vivo neutralization of interferon-gamma (IFN-gamma) demonstrated a significant decrease of FVE-induced anti-tumor effect (P<0.05). The expression levels of major histocompatibility complex (MHC) class I and II molecules and costimulatory molecule CD80 on peripheral blood mononuclear cells obtained from the FVE-treated mice were upregulated as compared with those of the PBS-treated mice. Furthermore, immunohistochemical staining showed a strong inhibition of tumor growth and angiogenesis in hepatoma tissues after oral administration of FVE. Taken together, oral administration of FVE displayed anti-tumor activity through activating both innate and adaptive immunity of the host to prime a cytotoxic immune response and IFN-gamma played a key role in the anti-tumor efficacy of FVE.