Secretion of TNF-alpha, IL-8 and nitric oxide by macrophages activated with Agaricus blazei Murill fractions in vitro

The immunobiology of mushrooms

There has been enormous interest in the biologic activity of mushrooms and innumerable claims have been made that mushrooms have beneficial effects on immune function with subsequent implications for inhibition of tumor growth. The majority of these observations are anecdotal and often lack standardization. However, there remains considerable data on both in vitro and in vivo effects that reflect on the potential of mushroom compounds to influence human immunity. A number of these effects are beneficial but, unfortunately, many responses are still characterized based on phenomenology and there is more speculation than substance. With respect to tumor biology, although many neoplastic lesions are immunogenic, tumor antigens frequently are self antigens and induce tolerance and many patients with cancer exhibit suppressed immune responses, including defective antigen presentation. Therefore, if and when mushroom extracts are effective, they more likely function as a result of improved antigen presentation by dendritic cells than by a direct cytopathic effect. In this review we attempt to place these data in perspective, with a particular focus on dendritic cell populations and the ability of mushroom extracts to modulate immunity. There is, at present, no scientific basis for the use of either mushrooms or mushroom extracts in the treatment of human patients but there is significant potential for rigorous research to understand the potential of mushrooms in human disease and thence to focus on appropriate clinical trials to demonstrate effectiveness and/ or potential toxicity.

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.

An extract of the mushroom Agaricus blazei Murill protects against lethal septicemia in a mouse model of fecal peritonitis

Bacterial septicemia is frequently occurring during gastroenterological surgery. Because of increasing problems in hospitals with bacteria developing multiresistance against antibiotics, prophylactic treatment using immunomodulators is interesting. We have examined the putatively anti-infective immunomodulatory action of the edible mushroom, Agaricus blazei Murill (AbM), in an experimental peritonitis model in BALB/c mice. The mice were orally given an extract of AbM or phosphate-buffered saline 1 day before the induction of peritonitis with various concentrations of feces from the mice. The state of septicemia, as measured by the number of colony-forming units of bacteria in blood, and the survival rate of the animals were compared between the groups. Mice that were orally treated with AbM extract before bacterial challenge showed significantly lower levels of septicemia and improved survival rates. Our findings suggest that the AbM extract, when given prophylactically, may improve health. Further studies are needed on humans when considering whether AbM could be used as an alternative treatment modality for patients at risk of contracting serious bacterial peritonitis.

Effects of AZT and RNA-protein complex (FA-2-b-β) extracted from Liang Jin mushroom on apoptosis of gastric cancer cells

AIM: To investigate the synergistic effects of 3'-azido-3'-deoxythymidine (AZT) and FA-2-b-β extracted from Ling Jin mushroom on apoptosis of gastric cancer cells MKN45 in vitro.

METHODS: MTT analysis was made to examine the inhibition rate of MKN45 cells treated with AZT (2.5, 5, 10 and 20 mg/L) and FA-2-b-β (5, 10, 20 and 40 mg/L) singly and combinatively for 24, 48 and 72 h. Apoptotic effects were evaluated by morphological methods, DNA agarose gel electrophoresis and flow cytometry, respectively. Telomerase activity was estimated by TRAP-ELISA. The mRNA expression of caspase-3 and Bcl-2 were detected by RT-PCR.

RESULTS: AZT and FA-2-b-β could significantly inhibit MKN45 cell proliferation and induce its apoptosis. MKN45 cells were inhibited in dose- and time- dependent manner. The inhibition effect of AZT combined with FA-2-b-β was obviously better than that used singly (0.469 ±0.022 vs 1.075 ± 0.055, P < 0.05, 0.325 ± 0.029 vs 0.469± 0.022 P < 0.01). AZT used singly and combination of FA-2-b-β could decrease the activity of tumor cell telomerase, and AZT has synergistic function with FA-2-b-β. A certain concentration of AZT could up-regulate the expression of caspase-3 mRNA (r = 0.9969, P < 0.01), which was positively related to apoptosis rate, and could down-regulate the expression of Bcl-2 mRNA, which was negatively related to apoptosis rate (r = 0.926, P < 0.01). Furthermore, the effect of AZT combined with FA-2-b-β was significantly higher than that used singly.

CONCLUSION: Combination of AZT and FA-2-b-β has an obviously synergetic effect in the gastric cancer cells MKN45, which has provided a new approach to the treatment of gastric cancer clinically.

Effect of an extract of the mushroom Agaricus blazei Murill on expression of adhesion molecules and production of reactive oxygen species in monocytes and granulocytes in human whole blood ex vivo

We have reported that an extract of the edible officinal mushroom Agaricus blazei Murill (AbM) stimulates synthesis of pro-inflammatory cytokines in human monocytes and vein endothelial cells in vitro and reduces the extent of lethal septicemia in mice with bacterial peritonitis. In the present study on human monocytes and granulocytes in whole blood ex vivo, we studied the dynamic changes of cell adhesion molecules (CD11b, CD62L) and the production of reactive oxygen species (ROS) after stimulation with AbM. The presence of AbM resulted in a similarly increased expression of CD11b in monocytes and granulocytes, although at a lower AbM concentration in monocytes (0.5%) than in granulocytes (2%). Furthermore, there was an AbM-mediated decrease in CD62L expression mirroring the effect on CD11b expression regarding magnitude and dose response. The intracellular production of ROS increased slightly but significantly in granulocytes, but not in monocytes stimulated with AbM. The results suggested that the major effect of AbM on monocytes and granulocytes was the upregulation of CD11b expression, thereby increasing both the phagocytic potential and the ablility to induce diapedesis into inflammatory foci. The rich beta-glucan content of AbM could play a crucial role in this immune response.

Therapy of Myeloma In Vivo Using Marine Phospholipid in Combination with Agaricus blazei Murill as an Immune Respond Activator

Mushroom (Agaricus blazei Murill) extract has been reported to possess antitumor effects through immune activation. Here, we investigated the beneficial effects of combining A. blazei extract with marine phospholipids in comparison to A. blazei extract alone on myeloma sp2 tumor suppression when orally administrated. The experimental groups designed for sp2 tumor bearing BALB/c nu/nu mice were drinks of: (1)control; (2)1.0 mg/mL squid phospholipid liposome alone; (3)0.5 mg/mL A. blazei Murill water extract alone; (4)1.0 mg/mL squid phospholipid liposome with 0.5 mg/mL A. blazei Murill water extract in the form of those simple mixture; and (5)1.0 mg/mL squid phospholipid liposome with 0.5 mg/mL A. blazei Murill water extract partially encapsulated. Orally administrated volumes amounted to approximately 5 mL per day per mouse for all groups. A. blazei Murill water extract alone and squid phospholipid alone served groups show moderate tumor suppression with total administrations of approximately 105 mg/mouse for squid phospholipid through out the experimental term. When both A. blazei Murill water extract and squid phospholipid were administrated simultaneously in a simple mixture form, promotional effect on cancer tumor suppression was observed. And when A. blazei Murill water extract was partially encapsulated in the squid phospholipid liposomes with total administrations being 105 mg/mouse for squid phospholipid, effect on cancer tumor suppression was more pronounced. Though there was no statistically significant difference in tumor sizes between the simple mixture form administrated group i.e. group (4) and the partially encapsulated form administrated group i.e. group (5), the tumor vanished mouse was seen in the partially encapsulated form administrated group. Thus it was concluded that combinational administration of the A. blazei Murill water extract and the marine phospholipid may be useful in myeloma sp2 therapy.

An Extract of the Medicinal Mushroom Agaricus blazei Murill Differentially Stimulates Production of Pro-inflammatory Cytokines in Human Monocytes and Human Vein Endothelial Cells in vitro

An extract of the edible mushroom Agaricus blazei Murill (AbM) has known antitumor and anti-infection properties, probably mainly by stimulating mononuclear phagocytes of the native immune system. The aim of this work was to study the effect of AbM on the production by human monocytes and human umbilical vein endothelial cells (EC) of pro-inflammatory cytokines (IL-1beta, IL-6, IL-8, TNFalpha), the anti-inflammatory/T regulatory cytokine IL-10 and the pro-Th1 cytokine IL-12. AbM, in concentrations from 1-15%, induced a considerable and dose-dependent increase in production of IL-8, IL-6, TNFalpha and IL-1beta in monocyte cultures. The biosynthesis reached a plateau at a concentration of 10% of AbM, and was most pronounced for the three former cytokines. AbM did also dose-dependently stimulate EC production of IL-8,I L-6 and TNFalpha, but at lower levels compared with the monocytes. AbM did neither induce synthesis of cytokines IL-10 nor IL-12 in monocytes or EC. Our results demonstrate the differential effect of AbM stimulation on the magnitude of pro-inflammatory cytokines produced by monocytes and EC.

Delayed Cell Cycle Progression and Apoptosis Induced by Hemicellulase-Treated Agaricus blazei

We examined the effects of hemicellulase-treated Agaricus blazei (AB fraction H, ABH) on growth of several tumor cell lines. ABH inhibited the proliferation of some cell lines without cytotoxic effects. It markedly prolonged the S phase of the cell cycle. ABH also induced mitochondria-mediated apoptosis in different cell lines. However, it had no impact on the growth of other cell lines. ABH induced strong activation of p38 mitogen-activated protein kinase (MAPK) in the cells in which it evoked apoptosis. On the other hand, ABH showed only a weak p38 activation effect in those cell lines in which it delayed cell cycle progression with little induction of apoptosis. However, p38 MAPK-specific inhibitor inhibited both ABH-induced effects, and ABH also caused apoptosis in the latter cells under conditions of high p38 MAPK activity induced by combined treatment with TNF-α. These results indicate that the responsiveness of p38 MAPK to ABH, which differs between cell lines, determines subsequent cellular responses on cell growth.

Control of cytokine gene expression by PG101, a water-soluble extract prepared from Lentinus lepideus

A water-soluble extract from Lentinus lepideus mycelium, named PG101, has been shown to control the expression of various cytokines [M. Jin, H.J. Jung, J.J. Choi, H.Jeon, J.H. Oh, B. Kim, S.S. Shin, J.K. Lee, K. Yoon, S. Kim, Activation of selective transcription factors and cytokines by water-soluble extract from Lentinus lepideus, Exp. Biol. Med. (Maywood) 228 (2003) 749-758]. To understand its molecular mechanism(s), PG101-mediated activation of cytokines was studied at the RNA and protein levels. Results from Northern blot analysis indicated that the steady-state RNA levels of TNF-alpha and seven other cytokines were highly increased in human peripheral blood mononuclear cells treated with PG101. The RNA level of TNF-alpha, MIP-1alpha, MIP-1beta, MIP-3alpha, and IL-8 was not affected by the presence of cycloheximide, an inhibitor of the translation process, suggesting that they are the direct targets of PG101. A significantly high protein level of TNF-alpha, MIP-1alpha, and IL-8 remained detectable, even when cells were cultured with actinomycin D, 2h prior to the PG101 treatment. Our data indicate that PG101 controls selective cellular proteins, which play key roles in the innate immune system, at the transcriptional and post-translational levels.

An extract of the mushroom Agaricus blazei Murill administered orally protects against systemic Streptococcus pneumoniae infection in mice

The aim was to investigate the antibacterial effect of the biologically active and edible mushroom Agaricus blazei Murill (AbM). A water extract of AbM or PBS control was administered orally before or with challenge to NIH/OlaHsd mice, experimentally infected intraperitoneally with the moderately virulent Streptococcus pneumoniae serotype 6B. End points were bacteraemia and survival rate. The AbM extract, protected against systemic S. pneumoniae 6B infection in the mice. It was most effective when given 24 h before inoculation but did also have protective effects when given together with challenge compared with control. The lack of antibiotic effect on pneumococci in vitro and increased levels of cytokines MIP-2 and TNF-alpha in the serum of mice receiving AbM extract, indicated that the protective effect of AbM was due to the involvement of the native immune system. This is the first report of anti-infection effects of AbM in vivo. Our results suggest that AbM extract may be useful as additional prophylactic and possibly therapeutic treatment against bacterial and possibly other infections in humans.

Effect of a medicinal extract from Agaricus blazei Murill on gene expression in a human monocyte cell line as examined by microarrays and immuno assays

Extracts from the edible mushroom Agaricus blazei Murill (AbM) are used extensively as a non-prescription remedy against cancer, infections, and immune related diseases. The presumed effect is to activate certain parts of the immune system. In order to investigate the effect, we examined the changes of gene expression caused by the extract on a human monocyte cell line (THP-1). Changes in the levels of mRNA transcripts were measured using 35 k microarrays, and the changes in select cytokine gene products by immuno assays. Lipopolysaccharide (LPS) was included for comparison. Both AbM and LPS had drastic effects on gene expression. Genes related to immune function were selectively up-regulated, particularly proinflammatoric genes such as the interleukins IL1B and IL8. Although most genes induced by AbM were also induced by LPS, AbM produced a unique profile, e.g., as to a particular increase in mRNA for the cytokines IL1A, CXCL1, CXCL2 and CXCL3, as well as PTGS2 (cyclooxygenase2).

Antiinflammatory and immunomodulating properties of fungal metabolites

We discuss current information on the ability of extracts and isolated metabolites from mushrooms to modulate immune responses. This can result in a more enhanced innate and acquired disease resistance. The major immunomodulating effects of these active substances derived from mushrooms include mitogenicity and activation of immune effector cells, such as lymphocytes, macrophages, and natural killer cells, resulting in the production of cytokines, including interleukins (ILs), tumor necrosis factor alpha (TNF)-alpha, and interferon gamma (INF)-gamma. In particular, the ability of selective mushroom extracts to modulate the differentiation capacity of CD4(+) T cells to mature into T(H)1 and/or T(H)2 subsets will be discussed. As a consequence these extracts will have profound effects in particular diseases, like chronic autoimmune T(H)1-mediated or allergic T(H)2-mediated diseases. Immunosuppressive effects by mushroom components have also been observed. The therapeutic effects of mushrooms, such as anticancer activity, suppression of autoimmune diseases, and allergy have been associated with their immunomodulating effects. However, further studies are needed to determine the molecular mechanisms of the immunomodulating effects of mushrooms metabolites both individually and in complex mixtures, for example, extracts.

Antithetical effects of hemicellulase-treated Agaricus blazei on the maturation of murine bone-marrow-derived dendritic cells

We report the effects of hemicellulase-treated Agaricus blazei (ABH) on the maturation of bone-marrow-derived dendritic cells (BMDCs). ABH activated immature BMDCs, inducing up-regulation of surface molecules, such as CD40, CD80 and major histocompatibility complex class I antigens, as well as inducing allogeneic T-cell proliferation and T helper type 1 cell development. However, unlike lipopolysaccharide (LPS), ABH did not stimulate the BMDCs to produce proinflammatory cytokines, such as interleukin-12 (IL-12) p40, tumour necrosis factor-alpha, or IL-1beta. In addition, ABH suppressed LPS-induced DC responses. Pretreatment of DCs with ABH markedly reduced the levels of LPS-induced cytokine secretion, while only slightly decreasing up-regulation of the surface molecules involved in maturation. ABH also had a significant impact on peptidoglycan-induced or CpG oligodeoxynucleotide-induced IL-12p40 production in DCs. The inhibition of LPS-induced responses was not associated with a cytotoxic effect of ABH nor with an anti-inflammatory effect of IL-10. However, ABH decreased NF-kappaB-induced reporter gene expression in LPS-stimulated J774.1 cells. Interestingly, DCs preincubated with ABH and then stimulated with LPS augmented T helper type 1 responses in culture with allogeneic T cells as compared to LPS-stimulated but non-ABH-pretreated DCs. These observations suggest that ABH regulates DC-mediated responses.

Effect of water-soluble proteoglycan isolated from Agaricus blazei on the maturation of murine bone marrow-derived dendritic cells

Water-soluble proteoglycan (WSPG) of Agaricus blazei Murill has been known to stimulate the non-specific complements and humoral immune functions to act as polyclonal activators of B cells and to inhibit tumor growth and metastasis. However, little is known about its immunomodulating effects on murine bone marrow (BM)-derived dendritic cells (DC). In the present study, we examined the maturation process of murine BM-DC. BM cells were cultured in the presence of IL-4 and GM-CSF and the generated immature DC were stimulated with WSPG or LPS (WSPG-DC and LPS-DC, respectively) for 24 h. WSPG significantly enhanced the expression of co-stimulatory molecules (CD80 and CD86) and major histocompatibility complex (MHC) II, as did LPS. IL-12p70 production in WSPG-DC was also identical to that in LPS-DC. The antigen-uptake capacity of WSPG-DC was determined by FITC-labeled dextran uptake. WSPG-DC lost dextran uptake capacity comparable to LPS-DC. The antigen-presenting capacity of WSPG-DC as analyzed by allogeneic T cell proliferation was significantly increased in comparison with immature DC, was identical to LPS-DC, and induced higher levels of IL-2 in responding T cells. These results indicate the immunomodulatory properties of WSPG, which might be therapeutically useful in the control of cancers and immunodeficient diseases through the up-regulation of DC maturation.

Coimmunization of Agaricus blazei Murill extract with hepatitis B virus core protein through DNA vaccine enhances cellular and humoral immune responses

DNA vaccines induce protective humoral and cell-mediated immune responses in several animal models. Agaricus blazei Murill (ABM) is particularly rich in polysaccharides, and has shown particularly strong results in treating and preventing cancers. The goal of this study was to investigate whether co-immunization of the fungus ABM with hepatitis B virus (HBV) core DNA vaccine could increase the immune responses. Compared with the control mice which received hepatitis B virus core antigen (HBcAg) alone, significant increase in not only the HBcAg-specific antibody response but also T cell proliferation was observed in mice which received HBcAg DNA vaccine plus ABM extract. These results suggest that ABM extract might represent an adjuvant to improve the efficacy of DNA vaccines in vivo.

Natural killer cell activity and quality of life were improved by consumption of a mushroom extract, Agaricus blazei Murill Kyowa, in gynecological cancer patients undergoing chemotherapy

A mushroom extract, Agaricus blazei Murill Kyowa (ABMK), has been reported to possess antimutagenic and antitumor effects. Here, we investigate the beneficial effects of ABMK consumption on immunological status and qualities of life in cancer patients undergoing chemotherapy. One hundred cervical, ovarian, and endometrial cancer patients were treated either with carboplatin (300 mg / m(2)) plus VP16 (etoposide, 100 mg / m(2)) or with carboplatin (300 mg / m(2)) plus taxol (175 mg / m(2)) every 3 weeks for at least three cycles with or without oral consumption of ABMK. We observed that natural killer cell activity was significantly higher in ABMK-treated group (ANOVA, n = 39, P < 0.002) as compared with nontreated placebo group (n = 61). However, no significant difference in lymphokine-activated killer and monocyte activities was observed in a manner similar to the count of specific immune cell populations between ABMK-treated and nontreated groups. However, chemotherapy-associated side effects such as appetite, alopecia, emotional stability, and general weakness were all improved by ABMK treatment. Taken together, this suggests that ABMK treatment might be beneficial for gynecological cancer patients undergoing chemotherapy.

IL-12 Production Induced by Agaricus blazei Fraction H (ABH) Involves Toll-like Receptor (TLR)

Agaricus blazei Murill is an edible fungus used in traditional medicine, which has various well-documented medicinal properties. In the present study, we investigated the effects of hemicellulase-derived mycelia extract (Agaricus blazei fraction H: ABH) on the immune system. First, we examined the cytokine-inducing activity of ABH on human peripheral mononuclear cells (PBMC). The results indicated that ABH induced expression of IL-12, a cytokine known to be a critical regulator of cellular immune responses. Flow cytometric analysis demonstrated the induction of IL-12 production by the CD14-positive cell population, consisting of monocytes/macrophages (Mo/Mphi). Furthermore, the elimination of Mo/Mphi attenuated IL-12 production in PBMC. ABH-induced IL-12 production was inhibited by anti-CD14 and anti-TLR4 antibodies but not by anti-TLR2 antibody. The activity of ABH was not inhibited by polymyxin B, while the activity of lipopolysaccharide used as a reference was inhibited. Oral administration of ABH enhanced natural killer (NK) activity in the spleen. These findings suggest that ABH activated Mo/Mphi in a manner dependent on CD14/TLR4 and NK activity.

Anticlastogenic effect of aqueous extracts of Agaricus blazei on CHO-k1 cells, studying different developmental phases of the mushroom

The Agaricus blazei Murill (ABM) mushroom, known as the sun mushroom, is native to Brazil and has become known for its medicinal properties. This study examined the anticlastogenic effect of Agaricus blazei in Chinese hamster ovary cells, CHO-k1, by means of a chromosome aberration test using methyl methanesulphonate (MMS, 10(-4)M) as the DNA damage inducing agent. Two mushroom lines were used, ABM 99/26 and ABM 97/11, and the latter was used in the young (Y) and sporulating (S) developmental phases. The cells were treated for 12 h with MMS alone or combined with aqueous extracts of A. blazei at a final concentration of 0.15%, which were prepared at three different temperatures: (a) hot (60 degrees C), (b) room temperature (25 degrees C) and (c) chilled (4 degrees C). Mushroom extracts showed a marked anticlastogenic effect against DNA damage, as evidenced by a decrease in the number of cells with breaks, regardless of the line used, or the developmental stage or the temperature at which the extract was prepared. Generally, the extracts were more effective in reducing the isochromatid type breaks. The data obtained suggest that extracts of A. blazei mushroom are anticlastogenic under the conditions tested, mainly during the G1 and S stages of the cell cycle, where chromosome breaks of the isochromatid type are produced by the MMS agent.

Antimetastatic and immunomodulating properties of a new herbal prescription, Bojung-bangam-tang

We investigated the antimetastatic effect of Bojung-bangam-tang, a new herbal prescription, on liver metastasis by the inoculation of colon 26-L5 carcinoma cells into the portal vein. Oral administration of Bojung-bangam-tang for 15 days from day 7 before tumor inoculation significantly inhibited liver metastasis in a dose-dependent manner. Bojung-bangam-tang enhanced the mitogenic activity of BALB/c whole splenocytes induced by various mitogenic stimuli. Oral administration of Bojung-bangam-tang, by itself, could not induce the production of interleukin (IL)-12 or IFN-gamma by macrophages, but enhanced the potential of macrophages to produce cytokines in response to lipopolysaccharide (LPS). Experiments using macrophage- or natural killer (NK) cell-deficient mice revealed that the antimetastatic effect of Bojung-bangam-tang is mediated by macrophages rather than NK cells. Bojung-bangam-tang caused a marked increase of production of Th1 cytokine (IFN-gamma) and decrease of production of Th2 cytokine (IL-4) by splenocytes stimulated with concanavalin A (Con A). These results indicated that oral administration of Bojung-bangam-tang inhibited the liver metastasis of colon 26-L5 cells through a mechanism leading to a Th1 dominant immune state and activation of macrophages. Thus, Bojung-bangam-tang may be useful for the prevention of cancer metastasis.