Received Date: August 09, 2021; Accepted Date: August 23, 2021; Published Date: August 30, 2021
Citation: Kumar S, Kumari R (2021) Traditional Uses, Phytochemistry and Biological Activities of Agaricus blazei murrill: A Comprehensive Review. Am J Pharmacol Pharmacother Vol.8 No.3:14.
Agaricus blazei murrill is an important medicinal and edible mushroom species, widely cultivated in Japan and native to Brazil. Different in vivo and in vitro studies describe its ant mutagenic and immunomodulatory properties however, it is not still clear that what chemical substances and biological pathways are responsible for these properties. It is assumed that the polysaccharides phytocomplex may be responsible for the antitumor and immunostimulant activities, through an opsonizing biochemical pathway. A. blazei is used to cure dermatitis, hepatitis, diabetes, therosclerosis, hyperlipidemia, and cancer in traditional medicine. The present review provides a comprehensive review on traditional, phytochemical and pharmacological aspects of A. blazei.
Agaricus blazei; Phytochemical constituents; Pharmacological activity; Traditional uses
The Agaricus blazei Murill a basidiomycete fungus, belonging to the Agaricaceae family, is native to southern Brazil and was introduced to Japan around 1950s . In 1945, an American mycologist named William Alphonso Murrill described A. blazei in ‘Quarterly Journal of the Florida Academy of Science’ . It is now commonly cultivated in Japan, China and Brazil [3,4] and used to cure atherosclerosis, hepatitis, hyperlipidaemia, diabetes, dermatitis, cancer and several other diseases . Several clinical studies proved its significant effects on immune system. It increases the number of white blood cells, activity of natural killer cells, and production of tumor necrosis factor-alpha. Sodium pyro glutamate and ergo sterol, an antitumor and anti-angiogenic substances are also identified in this species which cut off the blood supply to tumors and inhibit angiogenesis . A. blazei favours the humid, hot-house environment of its native Brazil. A. blazei popularly known as “Himematsutake” or “Brazilian mushroom” has been traditionally used as a health food supplement for the prevention of cancer, diabetes, hyperlipidemia, arteriosclerosis and chronic hepatitis . In recent years, the mushroom is used in Japan as an adjuvant in cancer chemotherapy . Polysaccharide is one of the main chemical constituents of A. blazei . The content of polysaccharides contains many kinds of water-soluble fractions such as β-(1-6)-D-glucan and β-(1-3)-glucan with β-(1-6)-glycosyl branching. It is well known that β-D-glucan is the key compound for expression of the antitumor activity and immune modulating functions . Various studies also revealed that the A. blazei extracts significantly inhibit the growth of various types of tumor cells, including sarcoma-180, Lewis lung carcinoma, Ehrlich ascites carcinoma, and Shionogi carcinoma in mice in vivo [11,12] and human ovarian cancer HRA cells in vitro . The extracts also showed anti-tumor activities related to induction of apoptosis, cell-cycle arrest, inhibition of tumor-induced neovascularization, immunopotentiation and restoration of tumor-suppressed host immune system [13-15] and inhibition of human leukemic cells [16,17]. Bactericidal and fungicidal effects of Agaricus sp. have also been reported [18,19]. The available information on this species was collected from scientific databases such as PubMed, SciFinder, Science Direct, Scopus, Web of Science, and Google Scholar. The search terms used for this review included Agaricus blazei, phytochemical composition, traditional uses, activity, pharmacology, and toxicity.
Pileus subcylindric to subexpanded, scattered or gregarious, 7- 9 cm broad; surface finely scaly, cremeous to ochraceous, margin glabrous, white, even, entire, projecting 5 mm.; context white, unchanging. 1-1.5 cm thick, not amygdaline; lamellae free, inserted, close, 5 mm broad, entire, pale; spores ellipsoid or ovoid, smooth, dark, opaque, about 5 × 4 μm; sterile cells on edges of gills scarce, hyaline, irregularly elavate; stipe equal, solid, white, ochraceous when bruised, 5-6 × 1.5-2 cml annulus large, white, median, simple .
Chemical constituents: Agaricus blazei contains agaritine , α and β-glucans [21,22], phenylhexane derivatives (1, 2), benzoylergostane (3), N-benzoyl-L-leucine methyl ester (4), ergostanes, incisterol , blazeispirols A(1), B(2), C(3), D(4), E(5), F(6), X(7), Y(8) and Z(9) , acetic, aconitic, benzoic, citric, fumaric, malic, oxalic, α-ketoglutaric, Ergosterol, C Vitamin, B1 Vitamin, B2 Vitamin, B9 Vitamin, B12 Vitamin, PP Vitamin , polysaccharide WABM-A-b .
Anti-cancer activity: Matsushita and co-workers studied the anti-cancer activity of the hot water extract of A. blazei against human pancreatic cancer cell lines such as MIAPaCa-2, PCI-35, and PK-8 and the immortalized human pancreatic duct-epithelial cell line, HPDE. They observed that HPDE was less sensitive, i.e., more resistant, to AbE than pancreatic cancer cell lines. The GI50 values of AbE treatment for the tested cell lines were 0.015% for MIAPaCa-2, 0.012% for PCI-35, 0.009% for PK-8, and 0.094% for HPDE which indicated that AbE significantly and specifically inhibited the proliferation of pancreatic cancer cells relative to that of normal duct-epithelial cells .
Kim et al., obtained various hydro alcoholic extract at room temperature (25°C) and from fruiting bodies of A. blazei (80°C) and studied their anti-tumor effects against human acute promyelocytic leukemic cell line NB-4 by using MTT assay. Among the tested extract, 70% (v/v) ethanol-water, 80◦C (JAB80E70) extract exhibited highest 82.6% suppression of growth of NB-4 calls with lowest IC50 value of 82.2 μg/ml .
Protective effect: Song et al. evaluated the protective effect of the polysaccharides isolated from aqueous extract of A. blazei(ABP) were against Cd-induced damage on the testis of chicken. They observed ABP improved Cd-caused testicular tissue damage by increasing the SOD and GSH-Px activities decreasing the Cd accumulation and MDA content, mRNA levels of TNF-α, IL-1β, and IL-6, and protein expressions of HSP60, HSP70, and HSP90 .
Hepatoprotective effect: The ethanolic extract of A. blazei mushroom (AbM) was evaluated for hepatoprotective effect against CCl4-induced liver injury in Male albino rats of Sprague- Dawley strain (120-150 g) by given orally in a dose of 0.5 g/kg body weight daily for 30 days, 48 hours. The CCl4 treated groups showed decrease levels of serum LDH5 (29.33), ALT (16.25), AST (05.70), GR (39.22), Vitamin C (mg/g) (228.12), Vitamin E (0.35), MDA (nmol/mg prot.) (11.36) and GSH (nmol/mg prot.) (14.65) compared to the control. This effect was reversed in the animal groups that were given AbM only and during treatment with CCl4 (therapeutic group, protective group). Malondialdehyde serum levels were significantly elevated in CCl4-treated groups as compared with control groups. Also, in therapeutic group and protective group where CCl4 was given side by side with mushroom, levels of malondialdehyde were found higher than control group. On the other hand, malondialdehyde, of animals treated with AbM alone remained within the levels of the control group .
Anti-neurotoxic effects: The methanolic extract of A. blazei showed effective anti-neurotoxic activity on rotenone-induced Parkinson’s disease in male Albino mice (25-30 g). The extract (50, 100, and 200 mg/kg b.w.) significantly improved the behavioral status of mice and showed neuroprotective effect by enhancing the depleted dopamine levels and minimizing the deleterious effect of neurotoxin as compared to control .
Apoptotic effect: The polysaccharides isolated from aqueous extract of A. blazei (ABP) were evaluated for apopototic effect on Cadmium-Induced apoptosis in Chicken. It was found that the ABP significantly increased the PBL apoptosis rate, mRNA levels of caspase-3 and Bax expression, while the expression of Bcl-2 was significantly reduced after 20, 40, and 60 days treatment. However, Bax/Bcl-2 ratio was significantly increased in the Cd group compared with control group [P29]. Similarly, isolated polysaccharides from A. blazei (ABP-Ia) were also evaluated for apopototic effect against human osteosarcoma cell lines (HOS) and normal human osteoblast cell line (NHOst) by using MTT assay. At 100, 200 and 400 μg/ml of ABP-Ia was significantly induced apoptosis in a dose-dependent manner in the HOS cells. However, ABP-Ia had no or minor inhibitory and cytotoxic effects on NHOst cells even at the high concentration of 400 μg/ml .
Anti-genotoxic effect: Dried powdered mycelial from A. blazei was evaluated for anti-genotoxic effect against hydrogen peroxide induced DNA damage in human peripheral blood cells by using comet assay. The anti-genotoxic effects of A. blazei were examined by pre and post treatment of mushroom with H O . At 500 μg/ml, pre-treatment of powder exhibited slightly significant reduction in number of damaged cells and attenuation in comparison to the control cells (treated with 50 μM H O ). However, at 250, 500 and 1000 μg/ml, all the tested concentration, significantly decrease the mean number of cells with DNA damage when compared with quercetin 100, 250, and 500 μg/ml, used as positive control .
Anti-oxidant effect: The antioxidant activity of A. blazei dried powdered extract was evaluated by using hydroxyl radical scavenging, reducing power and DPPH assay. Different concentration i.e., 0.062, 0.125, 0.25, 0.5, 1 and 2 mg/mL showed concentration-dependent but moderate reducing power ability i.e. 0.33, 0.62, 0.80, 0.99, 1.70 and 3.16%. At 2 mg/ml, mushroom showed only 3% inhibition of DPPH free radicals as compared to Trolox (96.25%). In hydroxyl radical scavenging assay, at tested concentration range, A. blazei showed IC50 values of 0.196 mg/ ml and Trolox used as standard exhibited 60% inhibition with IC50 value 0.023 mg/ml .
Similarly, the ethanolic extract, ethyl acetate and hydroalcoholic fractions were evaluated for their antioxidant activity by using DPPH and ABTS assay. Ethanolic extract, ethyl acetate and hydroalcoholic fractions were exhibited powerful antioxidant effect with IC50 values of 7.9, 7.61 and 7.24 μg/ml (in DPPH assay), and 22.82, 21.61 and 20.73 μg/ml (in ABTS assay), respectively as compared to trolox and uric acid used as reference .
Another study, γ-irradiated methanolic extract of A. blazei was evaluated for anti-oxidant effect by using DPPH, reducing power, hydroxyl radical scavenging and chelating assay. At 7.5 and 10.0 mg/ml, the antioxidant activities of methanolic extracts from 2.5 to 20 kGy γ-irradiated A. blazei increased by 19.9-55.7% and 8.8-35.7%, respectively. The methanolic extract from 20 kGy γ- irradiated A. blazei showed the best antioxidant activity (83.6%) at 10 mg/ml. However, the antioxidant activities were 98.8% at 10 mg/ml for ascorbic acid, 91.4% at 0.5 mg/ml for BHA and 94.8% at 0.5 mg/ml for α-tocopherol. For 0, 2.5, 5, 10, 15 and 20 kGy of irradiation, EC50 values in antioxidant activity were 27.6, 26.4, 21.4, 18.4, 19.3 and 20.3 mg sample/ml; EC50 values in reducing power were 3.15, 1.88, 4.92, 1.88, 2.30 and 2.93 mg sample/ ml; EC50 values in scavenging ability against DPPH radicals were 0.92, 0.96, 0.93, 0.81, 0.84 and 0.89 mg sample/ml; EC50 values in scavenging ability against hydroxyl radicals were 18.1, 28.6, 25.3, 23.5, 23.0 and 25.4 mg sample/ml; EC50 values in chelating ability against ferrous ions were 2.23, 2.98, 2.82, 2.22, 2.14 and 2.35 mg sample/ml, respectively .
The ethyl acetate extract showed stronger antioxidant activity, as well as inhibition of α-glucosidase, compared to ethanol extract of A. blazei using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical scavenging assays and the reducing power using K3Fe(CN)6 in vitro . Ethyl acetate extract also showed a better protective effect on hepatic antioxidant activity and recovery of the impaired pancreatic tissues .
Leishmanicidal activity: The aqueous extract of A. blazei was evaluated for leishmanicidal effect against Leishmania amazonensis, L. chagasi and L. major promastigote and amastigote-like stages. It was observed that the tested extract exhibited leishmanicidal effect against tested species with IC50 values of 67.5, 65.8, and 56.8 μg/ml for promastigotes stage and 115.4, 112.3, and 108.4 μg/ml for amastigotes, respectively .
Wound healing effect: The polysaccharides of A. blazei were evaluated for their burn wound healing effect on Sprague-Dawley rats. At 50 and 100 mg/kg b.w. dose, polysaccharides exhibited 45.7 and 63.2% recovery rate of skin wound as compared to control. The burn wound in rats’ skin induces the expression of IL-1β mRNA. Thus, the increase in the accumulation of macrophages in the burn wound area by the application of A. blazei polysaccharides suggests that a decreased production of IL-1β by macrophages may be related to the acceleration of wound repair .
Cytotoxic effect: The isolated compound agaritine from A. blazei was evaluated for cytotoxic effect against human monocytic leukemia U937 (human monocytic leukemia cell line; RCB0435) cell line by using MTT assay. The optical density of cells treated with agaritine for 48 h decreased by about 60% compared to the untreated cells, and this decrease was almost the same as that of Arabinosylcytosine (Ara-C) treatment for 24 hours. The death of agaritine-induced cell was partially inhibited by the coexistence of caspase-3 inhibitor. Cells treated with agaritine showed a 1.2 or 3.0 fold increase in caspase-3, 1.4 or 3.3 fold increase in caspase-8, and 1.4 or 4.8 fold increase in caspase-9, respectively, as compared to untreated cells. After 24 h of Ara-C treatment, all caspase activities increased 5.1-8.9 fold compared to untreated cells. Release of cytochrome c was increased in U937 cells incubated with agaritine for 48 h or Ara-C for 24 hours .
Guterres et al. studied the extract of A. blazei in lung cells of Chinese hamsters, in which 3 mg extract residues were diluted in 400 mL of dimethyl sulfoxide and 4600 mL of PBS, and a final concentration 60 mL/mL of this solution was applied to the comet assay. They observed a significant reduction of DNA damage caused by methyl methanesulfonate .
Angeli, et al. demonstrated that β-glucans extracted from A. blazei did not exert genotoxic or mutagenic effects at concentrations of 7, 21 and 63 μg/mL, and that there was also a dose-dependent protective effect against DNA damage caused by benzo[a]pyrene (20 μM) in a human hepatoma cell line (HepG2) by a comet assay . Silva, et al. studied the expression of CASP-9 in HepG2 cells treated for 6 h with non-sulfated β-glucans (50 mg/mL) extracted from A. blazei, and indicated that expression of β-glucans did not influence apoptotic cells .
Ex vivo experiments demonstrated that the Andosan extract (containing A. blazei (mycelium) (82.4%), Hericium erinaceus (14.7%), and Grifola frondosa (2.9%)) had a cytotoxic effect on primary myeloma cells, and also on myeloma and leukemia cell lines in vitro, probably caused by cell cycle arrest .
Anti-mutagenic effects: The anti-mutagenic effect of aqueous extracts of A. blazei, obtained at ice-cold (2-8 °C), room temperature (20-25°C) and warm (60°C), was evaluated against Methyl Methane Sulfonate (MMS) induced mutation in Chinese hamster lung V79 cells by using comet and Micronucleus (MN) assay. At 0.05, 0.1 and 0.15% concentrations, extract were used in MNS pre-treatment and post-treatment and result compared with negative control (PBS). In pre-treatment, the tested extracts exhibited anti-mutagenic effect in V79 cells in comet assay. However, in micronucleus assay, tested extracts exhibited efficient anti-mutagenic effect against MMS-induced number and percentage of MN with decreased frequent of micronuclei ranged in concentration dependent manner between the ranging from 61.5 (room temperature 0.1% tea in post-treatment) to 110.3% (co-treatment with warm and ice-cold 0.15% tea) .
Anti-inflammatory activity: The anti-inflammatory activity of aqueous and alkaline extracts of A. blazei was evaluated against nystatin induced paw edema in rats (150-200 g). At 300, 400, and 500 mg/kg of alkaline and aqueous extracts significantly inhibited 19, 33, and 39% and 12, 38, and 56% edema formation, respectively, as compared to control group. The aqueous and alkaline extracts (400 mg/kg) also decreased the ulceration index by 21.88% and 28.63% when compared to the control group .
Anti-diabetic effect: The β-glucans isolated from dried fruiting bodies of A. blazei was evaluated for anti-diabetic effect on streptozotocin induced diabetes in Sprague-Dawley rats (200 to 230 g). At 2% dose of β-glucans, significantly increased the levels of insulin secretion 3.79 ng/ml from pancreatic islets as compared to control 0.21 ng/ml .
Immuno-potentiating activity: The aqueous extract of A. blazei was evaluated for immuno-potentiating effect (antibody production) against sheep red blood cells antigen by using hemolytic plaque-forming cells (PFC) method. At 25 mg/kg dose, extract significantly increased the number of PFC in spleen (1.11 × 108 cells/spleen) when compared with control group (0.98 × 108 cells/spleen) .
Hyperlipidemia effects: The water extract of the total A. blazei Morrill acidic polysaccharides (WABM-A) was isolated from WABM using DEAE-cellulose, and subsequently purified using sepharose CL-6B to obtain the acidic polysaccharide WABM- Ab. In comparison with the model group, WABM-A significantly reduced the serum levels of total cholesterol, triglycerides and LDL-C, increased the serum levels of HDL-C, and up regulated the liver expression of PPARγ, LXRα, ABCA1, and ABCG1 in rats with hyperlipidemia. The in vitro experiments showed that in comparison with the model group, WABM-A-b-H significantly reduced the levels of total cholesterol and triglycerides in HepG2 cells induced by oleic acid, and significantly up regulated the protein expression of PPARγ, LXRα, ABCA1, and ABCG1 .
Several studies describe that A. blazei is rich in b-glucans which showed significant immunostimulatory activity however; we can’t deny the presence of other substances which can be involved in immunostimulatory activities. So, it become necessary to isolated and identifies other clinically beneficial substances to explore other pharmacological benefits of A. blazei as per its high consumption in popular medicine.