Antimutagenic effects of the mushroom Agaricus blazei Murrill extracts on V79 cells

Subcritical Water Extracts from Agaricus blazei Murrill's Mycelium Inhibit the Expression of Immune Checkpoint Molecules and Axl Receptor

Agaricus blazei Murrill or Himematsutake is an edible and medicinal mushroom. Agaricus blazei Murrill’s fruiting body extracts have anticancer properties, although the mechanism is unknown. Basic or organic solvents, which are hazardous for human health, are generally used to prepare Agaricus blazei Murrill’s extracts. The inhibition of immune checkpoint molecules and Axl receptor is an effective therapy in cancer. This study assessed whether subcritical water extracts of the Agaricus blazei Murrill’s fruiting body or mycelium affect the expression of Axl and immune checkpoint molecules in lung cancer cells. We used A549 cells and mouse bone marrow-derived dendritic cells in the experiments. We prepared subcritical water extracts from the Agaricus blazei Murrill’s fruiting body or mycelium. The subcritical water extracts from the Agaricus blazei Murrill’s fruiting body or mycelium significantly inhibited the expression of immune checkpoint molecules and Axl compared to saline-treated cells. Additionally, the hot water extract, subcritical water extract, and the hot water extraction residue subcritical water extract from the Agaricus blazei Murrill’s mycelium significantly enhanced the expression of maturation markers in dendritic cells. These observations suggest that the subcritical water extract from Agaricus blazei Murrill’s mycelium is a promising therapeutic tool for stimulating the immune response in cancer.

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.

Medicinal mushroom: boon for therapeutic applications

Medicinal mushrooms are higher fungi with additional nutraceutical attributes having low fat content and a trans-isomer of unsaturated fatty acids along with high fibre content, triterpenes, phenolic compounds, sterols, eritadenine and chitosan. They are considered as the unmatched source of healthy foods and drugs. They have outstanding attractive taste, aroma and nutritional value, so are considered as functional food, which means they are beneficial to the body not only in terms of nutrition but also for improved health. Medicinal mushrooms and their extract have a large number of bioactive components called secondary metabolites. The presence of polysaccharide β-glucans or polysaccharide-protein complexes content in mushroom extract have great therapeutic applications in human health as they possess many properties such as anti-diabetic, anti-cancerous, anti-obesity, immunomodulatory, hypocholesteremia, hepatoprotective nature along with anti-aging. The present review focuses on the comprehensive account of the medicinal properties of various medicinal mushrooms. This will further help the researchers to understand the metabolites and find other metabolites as well from the mushrooms which can be used for the potential development of the drugs to treat various life-threatening diseases.

Antigenotoxic Properties of Agaricus blazei against Hydrogen Peroxide in Human Peripheral Blood Cells

The ability of Agaricus blazei mushroom in its dried and powdered mycelial form was evaluated for its antigenotoxic properties for the first time. Antigenotoxic effects in human peripheral blood cells against H₂O₂-induced DNA damage were examined in pretreatment and posttreatment protocol by comet assay. The results showed better antigenotoxic properties of Agaricus blazei on the interventional level, respectively, after treatment. Agaricus blazei in concentration of 250 μg/mL after treatment was most efficient in regard to its action against DNA damage. The evaluation of repair kinetics showed decrease in H₂O₂ induced DNA damage 15 min after the application of A. blazei, reaching the maximum potency after 30 min. Analysis of antioxidant properties of Agaricus blazei revealed strong ^•OH scavenging properties and moderate reducing power, while its DPPH scavenging ability was weak. In regard to our findings, we can conclude that our preliminary results demonstrated antigenotoxic properties of Agaricus blazei and its strong ^•OH scavenging ability. Mechanisms underlying its properties should be further evaluated in in vivo studies.

Enhancement of the Th1-phenotype immune system by the intake of Oyster mushroom (Tamogitake) extract in a double-blind, placebo-controlled study

Pleurotus cornucopiae (Oyster mushroom, Tamogitake) has long been eaten as a functional food for enhancement of the immune system, but its effectiveness has not been well confirmed in humans. To this end, we set up a double-blind placebo-controlled human clinical trial to investigate the potential of Oyster mushrooms with respect to the up-regulation of the immune system. The subjects ingested Oyster mushroom extract for 8 weeks. We measured the serum cytokine levels involved in regulation of the immune system, including interferon (IFN)-γ, interleukin (IL)-4, IL-5, IL-10, IL-12, IL-13, and tumor-necrosis factor (TNF)-α. We found that intake of Oyster mushroom extract elevated IFN-γ (P = 0.013) and IL-12, whereas serum levels of IL-10 and IL-13 and other cytokines were minimally changed. We also measured natural killer (NK) cell activity, the levels of which tended to increase, but not significantly. Taken together, these facts suggest that Oyster mushrooms have the potential to enhance the immune system, through Th1 phenotype potentiation as the macrophage-IL-12 - IFN-γ pathway. This results in activation of the cell-mediated immune system as exemplified by up-regulation of NK cell activity. Oyster mushroom extract may be beneficial for the prevention of various diseases, including infectious diseases and cancer, due to its stimulation of the immune system.

Mushroom as a product and their role in mycoremediation

Mushroom has been used for consumption as product for a long time due to their flavor and richness in protein. Mushrooms are also known as mycoremediation tool because of their use in remediation of different types of pollutants. Mycoremediation relies on the efficient enzymes, produced by mushroom, for the degradation of various types of substrate and pollutants. Besides waste degradation, mushroom produced a vendible product for consumption. However, sometimes they absorb the pollutant in their mycelium (biosorption process) and cannot be consumed due to absorbed toxicants. This article reviews the achievement and current status of mycoremediation technology based on mushroom cultivation for the remediation of waste and also emphasizes on the importance of mushroom as product. This critical review is also focused on the safety aspects of mushroom cultivation on waste.

Effects of an Agaricus blazei aqueous extract pretreatment on paracetamol-induced brain and liver injury in rats

The action of an Agaricus blazei aqueous extract pretreatment on paracetamol injury in rats was examined not only in terms of the classical indicators (e.g., levels of hepatic enzymes in the plasma) but also in terms of functional and metabolic parameters (e.g., gluconeogenesis). Considering solely the classical indicators for tissue damage, the results can be regarded as an indication that the A. blazei extract is able to provide a reasonable degree of protection against the paracetamol injury in both the hepatic and brain tissues. The A. blazei pretreatment largely prevented the increased levels of hepatic enzymes in the plasma (ASP, ALT, LDH, and ALP) and practically normalized the TBARS levels in both liver and brain tissues. With respect to the functional and metabolic parameters of the liver, however, the extract provided little or no protection. This includes morphological signs of inflammation and the especially important functional parameter gluconeogenesis, which was impaired by paracetamol. Considering these results and the long list of extracts and substances that are said to have hepatoprotective effects, it would be useful to incorporate evaluations of functional parameters into the experimental protocols of studies aiming to attribute or refute effective hepatoprotective actions to natural products.

Antimutagenic effect of aqueous extract from Agaricus brasiliensis on culture of human lymphocytes

The mushroom Agaricus brasiliensis (sun mushroom), native from the southeast of Brazil, is well known by its medicinal properties that include effects on diabetes, cholesterol levels, and osteoporosis. The antimutagenic effects of A. brasiliensis has been investigated recently and revealed some controversial results depending on the temperature by which the A. brasiliensis tea is obtained. In the present study, we evaluated the effect of the A. brasiliensis extract prepared in two different temperatures, 4°C and 25°C, on the doxorubicin-induced DNA strand breaks and chromosomal aberrations (CAs) in human lymphocytes. The results demonstrated that A. brasiliensis was able to reduce the DXR-induced DNA damage in both temperatures; however, the CA test was more sensitive to demonstrate a better reduction when the cells were treated with an extract obtained at 25°C. A. brasiliensis extract obtained in different temperatures exhibited antigenotoxic and anticlastogenic effects in human lymphocytes.

Anti-inflammatory and anti-allergic effect of Agaricus blazei extract in bone marrow-derived mast cells

In this study, the anti-inflammatory and anti-allergic effects of the chloroform-soluble extract of Agaricus blazei in mouse bone marrow-derived mast cells (BMMCs) were investigated. The chloroform-soluble extract inhibited IL-6 production in PMA plus A23187-stimulated BMMCs, and down-regulated the phosphorylation of Akt. In addition, this extract demonstrated inhibition of the degranulation of β-hexosaminidase and the production of IL-6, prostaglandin D(2) and leukotriene C(4) in PMA plus A23187-induced BMMCs. In conclusion, the chloroform-soluble extract of Agaricus blazei exerted anti-inflammatory and anti-allergic activities mediated by influencing IL-6, prostaglandin D(2), leukotriene C(4), and the phosphorylation of Akt.

An extract of Agaricus blazei Murill administered orally promotes immune responses in murine leukemia BALB/c mice in vivo

PURPOSE

The edible mushroom (fungus) Agaricus blazei Murill (ABM) is a health food in many countries. Importantly, it has been shown to have antitumor and immune effects. There is no available information on ABM-affected immune responses in leukemia mice in vivo. Experimental Design. In this study, the authors investigated the immunopotentiating activities of boiled water-soluble extracts from desiccated ABM in WEHI-3 leukemia mice. The major characteristic of WEHI-3 leukemia mice are enlarged spleens and livers after intraperitoneal injection with murine leukemia WEHI-3 cells. Isolated T cells from spleens of ABM-treated mice resulted in increased T-cell proliferation compared with the untreated control with concanavalin A stimulation.

RESULTS

ABM decreased the spleen and liver weights when compared with WEHI-3 leukemia mice and this effect was a dose-dependent response. ABM promoted natural killer cell activity and phagocytosis by macrophage/monocytes in leukemia mice in a dose-dependent manner. ABM also enhanced cytokines such as interleukin (IL)-1β, IL-6, and interferon-γ levels but reduced the level of IL-4 in WEHI-3 leukemia mice. Moreover, ABM increased the levels of CD3 and CD19 but decreased the levels of Mac-3 and CD11b in leukemia mice.

CONCLUSIONS

The ABM extract is likely to stimulate immunocytes and regulate immune response in leukemia mice in vivo.

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.

Phase I Clinical Study of the Dietary Supplement, Agaricus blazei Murill, in Cancer Patients in Remission

Although many cancer patients use complementary and alternative medicine, including Agaricus blazei Murill (ABM), safety is not yet well understood. Cancer survivors took 1.8, 3.6, or 5.4 g ABM granulated powder (Kyowa Wellness Co., Ltd., Tokyo, Japan) per day orally for 6 months. Adverse events were defined by subjective/objective symptoms and laboratory data according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0 (NCI-CTCAE v3.0). Seventy-eight patients were assessed for safety of ABM (30/24/24 subjects at 1/2/3 packs per day, resp.). Adverse events were observed in 9 patients (12%). Most were digestive in nature such as nausea and diarrhea, and one patient developed a liver dysfunction-related food allergy, drug lymphocyte product. However, none of these adverse events occurred in a dose-dependent manner. This study shows that ABM does not cause problems in most patients within laboratory parameters at the dosages tested over 6 months. This trial supports previous evidence that the ABM product is generally safe, excluding possible allergic reaction.

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.

Antineoplasic activity of Agaricus brasiliensis basidiocarps on different maturation phases

The fungus Agaricus brasiliensis is a Basidiomycete studied because of its immunomodulation and/or antitumor substances. The objective of this study was to verify the Agaricus brasiliensis antineoplasic activity in vivo on different basidiocarp maturation phases on Sarcoma 180 cells implanted in mice. Sarcoma cells were implanted in mice and after seven days mice were divided in three groups. The first group was treated with saline solution, the second group was treated with closed basidiocarp extract solution and the third group was treated with opened basidiocarp extract solution. After 30 days of being daily orally treated with these three solutions all animals suffered euthanasia, and the splenic index, tumor mass and volume were determined. No significant differences of the tumor growth inhibition in function of the different basidiocarp maturation phases for the Agaricus brasiliensis strain were observed. The in vivo basidiocarp antineoplasic average activity was 89.22%.

Screening for in vitro and in vivo antitumor activities of the mushroom Agaricus blazei

We have investigated the in vitro antitumor activity of the mushroom Agaricus blazei Murill on human cancer cell lines as well as its potential anticancer activity in a model of rat colon carcinogenesis. The in vitro anticancer analysis was performed using 9 human cancer cell lines incubated with organic and aqueous extracts of A. blazei. Antitumor activity was observed with the dichloromethane/methanol and hexanic extracts of A. blazei at 250 mu g/ml for all cancer cell lines tested. No antiproliferative/cytotoxic activities were detected for the aqueous, methanol, ethyl acetate, or n-butanolic extracts. In the in vivo analysis, crude A. blazei was given orally after carcinogen treatment in a rat medium-term study (20 weeks) of colon carcinogenesis using aberrant crypt foci (ACF) as biomarker. Male Wistar rats were given dimethylhydrazine (DMH) and then were fed A. blazei at 5% in the diet until Week 20. ACF were scored for number and crypt multiplicity. A. blazei intake did not suppress ACF development or crypt multiplicity induced by DMH. No differences in tumor incidence in the colon were observed among the DMH-treated groups. Our results indicate that employing A. blazei in the diet does not have a suppressive effect on colon carcinogenesis.

Lack of chemopreventive activity of Agaricus blazei mushroom on the development of 1,2-dimethylhydrazine-induced colonic aberrant crypt foci in rats

Chemopreventive and immunomodulatory potential of methanolic (MET) and dichloromethanic (DCl) extracts of Agaricus blazei mushroom were investigated in the postinitiation stage of colon carcinogenesis in male Wistar rats. Animals were initiated with 1,2-dimethylhydrazine (DMH) and treated i.g. with DCl or MET extracts. After 9 wk, animals were sacrificed for evaluation of aberrant crypt foci (ACF) development, crypt cellular proliferation, preneoplastic liver lesions (GST-P), proliferative response of spleen cells to mitogen, and natural killer activity. Administration of DCl extracts did not suppress DMH-induced colonic ACF nor did it affect the crypt multiplicity, but the highest dose of MET significantly reduced the development of preneoplastic lesions in the colon and liver. Lymphoproliferative response was slightly decreased in the initiated control group, which was restored by treatment with MET. No toxicity from DCl and MET extracts was observed (groups MET and DCl).

Lack of chemoprevention of dietary Agaricus blazei against rat colonic aberrant crypt foci

The mushroom Agaricus blazei (Ab) has been widely used in folk medicine to treat various diseases including cancer. No information is available on its possible protective effects on the development of colon cancer. The potential blocking effect of Ab intake on the initiation stage of colon carcinogenesis was investigated in a short-term (4-week) bioassay using aberrant crypt foci (ACF) as biomarker. Male Wistar rats were given four subcutaneous injections of the carcinogen 1,2-dimethylhydrazine (DMH, 40 mg/kg bw, twice a week), during 2 weeks to induce ACF. The diet containing Ab at 5% was given 2 weeks before and during carcinogen treatment to investigate the potential beneficial effects of this edible mushroom on DMH-induced ACF. All groups were killed at the end of the fourth week. The colons were analyzed for ACF formation in 1% methylene blue whole-mount preparations and for cell proliferation in histological sections immunohistochemically stained for the proliferating cell nuclear antigen (PCNA). All DMH-treated rats developed ACF mainly in the middle and distal colon. Agaricus blazei intake at 5% did not alter the number of ACF induced by DMH or the PCNA indices in the colonic mucosa. Thus, the results of the present study did not confirm a chemopreventive activity of Ab on the initiation stage of rat colon carcinogenesis.

Inhibitory mechanisms of Agaricus blazei Murill on the growth of prostate cancer in vitro and in vivo

Agaricus blazei Murill (A. blazei) has been conventionally used as a health food for the prevention of cancer. However, little is known about the direct effects and action mechanisms of A. blazei on human prostate cancer. In the present study, the effects of A. blazei on the growth of human prostate cancer were examined in vitro and in vivo. A. blazei, especially the broth fraction, inhibited cell proliferation in both androgen-dependent and androgen-independent prostate cancer cell lines. The broth of A. blazei induced lactate dehydrogenase leakage in three cancer cell lines, whereas the activities of caspase 3 and the DNA fragmentation were enhanced the most in androgen-independent PC3 cells. The protein expressions of apoptosis-related molecules were elevated by the broth of A. blazei in PC3 cells. Oral supplementation with the broth of A. blazei (with the higher ratio of beta-glucan) significantly suppressed tumor growth without inducing adverse effects in severe combined immunodeficient mice with PC3 tumor xenograft. Tumor xenografts from A. blazei-fed mice showed decreased proliferating cell nuclear antigen-positive cells and reduced tumor microvessel density. Based on these results, we found that the broth of A. blazei may directly inhibit the growth of prostate cancer cell via an apoptotic pathway and suppress prostate tumor growth via antiproliferative and antiangiogenic mechanisms. We therefore suggest that A. blazei might have potential therapeutic use in the prevention and treatment of human prostate cancer.

The Medicinal Mushroom Agaricus blazei Murrill: Review of Literature and Pharmaco-Toxicological Problems

Agaricus blazei Murrill (ABM) popularly known as 'Cogumelo do Sol' in Brazil, or 'Himematsutake' in Japan, is a mushroom native to Brazil, and widely cultivated in Japan for its medicinal uses, so it is now considered as one of the most important edible and culinary-medicinal biotechnological species. It was traditionally used to treat many common diseases like atherosclerosis, hepatitis, hyperlipidemia, diabetes, dermatitis and cancer. In vitro and in vivo ABM has shown immunomodulatory and antimutagenic properties, although the biological pathways and chemical substances involved in its pharmacological activities are still not clear. The polysaccharides phytocomplex is thought to be responsible for its immunostimulant and antitumor properties, probably through an opsonizing biochemical pathway. Clinical studies are positive confirmations, but we are still at the beginning, and there are perplexing concerns especially relative to the content of agaritine. Argantine is a well-known carcinogenic and toxic substance in animals, that must be completely and fully evaluated.

Inhibitory effect of Agaricu blazei Murill components on abnormal collagen fiber formation in human hepatocarcinoma cells

Hot-water extracts of the mycelial culture and fruiting bodies of Agaricus blazei Murill were fractionated by ethanol precipitation, using various ethanol concentrations. The mycelial fraction (A-4) inhibited abnormal collagen fiber formation, and fractions A-1 to A-3 showed a small inhibitory effect. The strongest inhibition was obtained by fraction A-4, and no significant inhibition was observed with fractions A-5 and A-6. With the fruiting bodies, fractions B-1 to B-6 showed no inhibitory effects on collagen fiber formation in HCC. The reverse transcription-polymerase chain reaction (RT-PCR) demonstrates that Agaricus blazei mycelial fraction A-4 did not inhibit the type I, II or III procollagen gene expression.

Measuring perceived effects of drinking an extract of basidiomycetes Agaricus blazei Murill: a survey of Japanese consumers with cancer

Background

To survey cancer patients who consume an extract of the Basidiomycetes Agaricus blazei Murill mushroom (Sen-Sei-Ro) to measure their self-assessment of its effects and to develop an instrument for use in future randomized trials.

Methods

We designed, translated and mailed a survey to 2,346 Japanese consumers of Sen-Sei-Ro self-designated as cancer patients. The survey assessed consumer demographics, cancer history, Sen-Sei-Ro consumption, and its perceived effects. We performed exploratory psychometric analyses to identify distinct, multi-item scales that could summarize perceptions of effects.

Results

We received completed questionnaires from 782 (33%) of the sampled Sen-Sei-Ro consumers with a cancer history. Respondents represented a broad range of cancer patients familiar with Sen-Sei-Ro. Nearly all had begun consumption after their cancer diagnosis. These consumers expressed consistently positive views, though not extremely so, with more benefit reported for more abstract benefits such as emotional and physical well-being than relief of specific symptoms. We identified two conceptually and empirically distinct and internally consistent summary scales measuring Sen-Sei-Ro consumers' perceptions of its effects, Relief of Symptoms and Functional Well-being (Cronbach's alpha: Relief of Symptoms, α = .74; Functional Well-Being, α = .91).

Conclusion

Respondents to our survey of Sen-Sei-Ro consumers with cancer reported favorable perceived effects from its use. Our instrument, when further validated, may be a useful outcome in trials assessing this and other complementary and alternative medicine (CAM) substances in cancer patients.

Lack of carcinogenicity of lyophilized Agaricus blazei Murill in a F344 rat two year bioassay

The Brazilian mushroom Agaricus blazei Murill has antimutagenic, antioxidant, immunostimulatory and antitumorigenic activities, and is increasingly consumed as a health food worldwide. We undertook the present study to evaluate the chronic toxicity and oncogenicity of A. blazei Murill in F344 rats. To establish a no-observed-adverse-effect level (NOAEL), four treatment groups of 100 rats each (50 males and 50 females) were fed a powder diet containing lyophilized A. blazei aqueous extract at 0, 6250, 12,500, and 25,000 ppm for up to 2 years. During this period, there was no remarkable change in mean body weight, body weight gain, hematologic or serum chemistry parameters, or absolute or relative organ weights in control or treatment groups. Mortality in male treatment groups (26%, 16%, and 30%), however, was significantly lower than in controls (48%). Histopathological studies showed no increased incidence of tumors in any treatment group, and total tumor incidence across all groups was comparable to historical data. In conclusion, an A. blazei Murill lyophilized powder diet even at 25,000 ppm (1176 mg/kgb x w x /day for male rats and 1518 mg/kgb.w./day for female rats) resulted in no remarkable carcinogenic effects in F344 rats over a 2-year period. Therefore, the dietary NOAEL is 25,000 ppm.

Antiviral activity of aqueous and ethanol extracts and of an isolated polysaccharide from Agaricus brasiliensis against poliovirus type 1

AIMS

Agaricus brasiliensis (previously named Agaricus blazei ss. Heinem), also known as the sun mushroom is native of Southeast Brazil, and is widely consumed, mainly in the form of tea, due to its nutritional and pharmacological properties. In this study, we tested aqueous (AqE) and ethanol (EtOHE) extracts and an isolated polysaccharide (PLS) from the fruiting body of A. brasiliensis, for antiviral activity against poliovirus type 1 in HEp-2 cells.

METHODS AND RESULTS

The evaluation of the time of addition by plaque assay showed that when AqE, PLS and EtOHE were added, just after the virus inoculation (time 0 h), there was a concentration-dependent reduction in the number of plaques up to 50%, 67% and 88%, respectively, with a selectivity index (SI) of 5.4, 9.9 and 12.3, respectively.

CONCLUSIONS

The test substances showed antiviral activity and were more effective when added during the poliovirus infection. As they had little effect on reducing viral adsorption and did not show any virucidal effect, we suggest that they act at the initial stage of the replication of poliovirus.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results corroborate that basidiomycetes can be a rich source of potential antiviral compounds.

Immunomodulating and anticancer agents in the realm of macromycetes fungi (macrofungi)

Nowadays macrofungi are distinguished as important natural resources of immunomodulating and anticancer agents and with regard to the increase in diseases involving immune dysfunction, cancer, autoimmune conditions in recent years, applying such immunomodulator agents especially with the natural original is vital. These compounds belong mainly to polysaccharides especially beta-d-glucan derivates, glycopeptide/protein complexes (polysaccharide-peptide/protein complexes), proteoglycans, proteins and triterpenoids. Among polysaccharides, beta(1-->3)-d-glucans and their peptide/protein derivates and among proteins, fungal immunomodulatory proteins (Fips) have more important role in immunomodulating and antitumor activities. Immunomodulating and antitumor activity of these metabolites related to their effects to act of immune effecter cells such as hematpoietic stem cells, lymphocytes, macrophages, T cells, dendritic cells (DCs), and natural killer (NK) cells involved in the innate and adaptive immunity, resulting in the production of biologic response modifiers. In this review we have introduced the medicinal mushrooms' metabolites with immunomoduling and antitumor activities according to immunological evidences and then demonstrated their effects on innate and adaptive immunity and also the mechanisms of activation of immune responses and signaling cascade. In addition, their molecular structure and their relation to these activities have been shown. The important instances of these metabolites along with their immunomodulating and/or antitumor activities isolated from putative medicinal mushrooms are also introduced.

Shiitake (Lentinula edodes (Berkeley) Pegler) extracts as a modulator of micronuclei induced in HEp-2 cells

Shiitake (Lentinula edodes (Berkeley) Pegler) is one of the most consumed mushrooms, for both therapeutic purposes and as food, therefore, the study of its biological properties is of great interest for producers and consumers. Aqueous extracts of the shiitake mushroom (L. edodes (Berkeley) Pegler) were evaluated by the micronucleus test (MN) in HEp-2 cells in vitro, to analyze their possible mutagenic and antimutagenic activities. None of the three extract concentrations tested (0.5, 1.0 and 1.5mg/mL) presented mutagenicity at any of the preparation temperatures (4 degrees C, 22+/-2 degrees C and 60 degrees C). In the antimutagenicity evaluation, all extract concentrations at all preparation temperatures presented a strong protective activity for the HEp-2 cells in response to the alkylating agent methyl methanesulfonate (MMS) in the different treatment protocols: pre-treatment, simultaneous treatment and post-treatment. The extracts prepared at 22+/-2 degrees C presented the lowest frequencies of MN in the evaluations of mutagenicity and antimutagenicity, indicating these as the best option for potential therapeutic use.

Brazilian natural dietary components (annatto, propolis and mushrooms) protecting against mutation and cancer

Considering the high number of new cancer cases in Brazil (approximately 470000 cases in 2005) and the remarkable differences in the incidence of this disease around the world, the development of chemopreventive strategies using foods widely consumed would have a huge impact, both medically and economically. This review summarizes some of our studies conducted to verify the anti-mutagenic and anti-carcinogenic potential of some Brazilian natural dietary constituents (annatto, mushrooms, and propolis). Overall data have shown a clear role for these compounds in preventing mutation and specific preneoplastic lesions. Taken together, these agents indicate a favorable side-effect profile and may prove to be a promising alternative for cancer prevention strategies, although more investigation is needed to fully explore this issue.

Antimutagenic effect of neem leaves extract in freshwater fish, Channa punctatus evaluated by cytogenetic tests

Neem (Azadirachta indica), an indigenous plant commonly grown in India and its sub-continent is a multipurpose plant well known for its insecticidal and biomedical properties, however, its antimutagenic effects in vertebrate organisms are lacking. The present work is therefore, focused on possible antimutagenic potential of ethanolic extract of neem leaves evaluated on the clastogenicity induced by Pentachlorophenol (PCP) and 2, 4-dichlorophenoxyacetic acid (2,4-D) in freshwater fish, Channa punctatus used as a vertebrate model, by cytogenetic endpoints: chromosome aberration (CA) and micronucleus (MN) test. In the first set of experiment, fish were exposed by medium treatment to a single treatment of each chemical (PCP, 0.6 ppm; 2,4-D, 75 ppm; neem extract, 3 ppm) along with the controls. The chromosome preparations were made after processing kidney cells and micronucleus slides were prepared from peripheral blood at multiple duration (48, 72 and 96 h). PCP and 2,4-D when used alone, induced significant CA and MN in a time dependent manner. Neem extract did not show genotoxic potential in both assays. The maximum frequency of CA were recorded as 18.58% and 15.17%, while frequency of MN reached to 8.08% and 4.62% by PCP and 2,4-D respectively, after 96 h exposure. In the second set of experiment, three concentrations of neem extract (1, 2 and 3 ppm) were run simultaneously with the same concentration of PCP (0.6 ppm) and 2,4-D (75 ppm) for antimutagenicity estimates. In mixed treatment, neem extract significantly reduced the frequency of CA and MN. The reduction in the frequency of CA ranged from 40-75% and 45.4-83.3% and similar values for MN were 40.2-75.3% and 44.1-65.8% for PCP and 2,4-D respectively. Although the reductions were significant but not dependent on concentration and time intervals employed. Results suggested that under present experimental conditions, neem extract exhibit strong antimutagenic activity in this fish model, which could further contribute to study its benefit in humans.

Protective effects of β-glucan extracted from Agaricus brasiliensis against chemically induced DNA damage in human lymphocytes

beta-Glucans (BGs) are polysaccharides that are found in the cell walls of organisms such as bacteria, fungi, and some cereals. The objective of the present study was to investigate the genotoxic and antigenotoxic effects of BG extracted from the mushroom Agaricus brasiliensis (=Agaricus blazei Murrill ss. Heinemann). The mutagenic activity of BG was tested in single-cell gel electrophoresis assays with human peripheral lymphocytes. In addition, the protective effects against the cooked food mutagen 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and (+/-)-anti-B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), which is the main metabolite of B[a]P, and against ROS (H(2)O(2))-induced DNA damage, were studied. The results showed that the compound itself was devoid of mutagenic activity, and that a significant dose-dependent protective effect against damage induced by hydrogen peroxide and Trp-P-2 occurred in the dose range 20-80 microg/ml. To investigate the prevention of Trp-P-2-induced DNA damage, a binding assay was carried out to determine whether BG inactivates the amine via direct binding. Since no such interactions were observed, it is likely that BG interacts with enzymes involved in the metabolism of the amine.

Novel antimutagenic factors derived from the edible mushroom Agrocybe cylindracea

Studies have shown that certain foods contain compounds with antigenotoxic activities. Here, we ask if dried powders and/or extracts from three edible mushrooms, Agrocybe cylindracea, Lentinula edodes and Pleurotus ostreatus, have a mitigating effect on genotoxicity. We used two in vivo assays: the Drosophila DNA repair test and the Drosophila wing spot test (also known as SMART) which measures somatic mutation and recombination. Eight carcinogens were tested with the mushroom powders: 2-AAF, aflatoxin B1, DMBA, IQ, MeIQx, MNU NDMA, and 4NQO. We found that A. cylindracea and P. ostreatus powders can suppress DNA damage induced by each of the mutagens we tested. In contrast, L. edodes has an inhibitory effect on DNA damage induced by only a sub-set of mutagens, namely aflatoxin B1, NDMA, MNU and 4NQO. In addition, A. cylindracea extracts were able to suppress somatic cell mutation induced by aflatoxin B1, MMC, MNU, NDMA, NMOR and 4NQO. These results suggest that Agrocybe genus mushrooms contain factors with antigenotoxic activity, including anti-recombinogenic activity. Furthermore, the antigenotoxic activity of A. cylindracea powder can be extracted in water but not in ethyl acetate or methanol, and is sensitive to heat treatment. The data suggest that there is a novel antigenotoxic factor(s) in A. cylindracea, possibly in the form of a peptide or protein.

Antigenotoxicity of Agaricus blazei mushroom organic and aqueous extracts in chromosomal aberration and cytokinesis block micronucleus assays in CHO-k1 and HTC cells

Agaricus blazei (Ab) has become popularly known for its medicinal properties. Scientifically, it has been tested with regard to its capacity to protect genetic material against damage. We examined different organic extracts (methanolic extract -- ME, hexanic extract -- HE and n-butanolic extract -- BE) and an aqueous extract (AE) of Ab, for their capacity to induce DNA damage as well as for their protective effect. Genetic damage was determined by the chromosomal aberration assay (CA) in CHO-k1 cells for all extracts and the cytokinesis block micronucleus assay (CBMN) in non drug-metabolizing (CHO-k1) and drug-metabolizing (HTC) cell lines for extract BE only. The extracts did not show clastogenicity but showed anticlastogenicity. The greatest percent reduction obtained were with BE (105%) and AE (126%) treatments in CA. BE treatment did not display genotoxicity in CHO-k1, but was genotoxic in HTC. However, BE was shown to be antigenotoxic causing decreased micronucleus frequency in HTC and CHO-k1 cells. These results suggest that all the extracts contained protective substances, but in some cases they could show a genotoxic effect with regard to metabolism. Therefore, these findings warrant caution in the use of this mushroom by the population.

The pharmacological potential of mushrooms

This review describes pharmacologically active compounds from mushrooms. Compounds and complex substances with antimicrobial, antiviral, antitumor, antiallergic, immunomodulating, anti-inflammatory, antiatherogenic, hypoglycemic, hepatoprotective and central activities are covered, focusing on the review of recent literature. The production of mushrooms or mushroom compounds is discussed briefly.