Isolation of an anti‐angiogenic substance from Agaricus blazei Murill: Its antitumor and antimetastatic actions

Abstract

We previously found that ergosterol isolated from Agaricus blazei inhibited tumor growth through the inhibition of tumor-induced neovascularization. In the present study, we isolated further anti-angiogenic substances (A-1 and A-2) from this fungus using an assay system of angiogenesis induced by Matrigel supplemented with vascular endothelial growth factor, and A-1 was identified as sodium pyroglutamate. Next, we examined the antitumor and antimetastatic actions of A-1 using Lewis lung carcinoma ( he Basiodiomycete fungus Agaricus blazei Murill (Japanese name: Himematsutake or Agarikusutake) has been traditionally used as a health food in Brazil for the prevention of cancer, diabetes, hyperlipidemia, arteriosclerosis and chronic hepatitis. It has been reported that 200,000 to 400,000 kg of the dried body of A. blazei is produced every year in Japan.1, 2) A. blazei is used by 300,000 to 500,000 persons for the prevention of cancer and/or as an adjuvant with cancer chemotherapy drugs after the removal of a malignant tumor.1, 2) The water extract of A. blazei is generally administered at 3 to 5 g three times daily. The hot water extract of A. blazei has potent antitumor activity in sarcoma 180-bearing mice, [3][4][5][6] and the antitumor activity was postulated to reside in the β-(1-6) glucan fraction. 3-6)Previously we examined the antitumor activities of various substances isolated from the lipid fraction of A. blazei and identified ergosterol as an active substance. 7) We found that ergosterol inhibited tumor-induced neovascularization.7) Furthermore, we found that the acetone-soluble fractions of ethanol extracts inhibited tumor growth and lung metastasis in Lewis lung carcinoma (LLC)-bearing mice, and inhibited Matrigel-induced angiogenesis (unpublished data). In a preliminary experiment, we found a large amount of D-mannitol in the acetonesoluble fraction of the ethanol extracts. However, D-mannitol had no effect on Matrigel-induced angiogenesis in vivo (data not shown). Therefore, we prepared the methanol-soluble fraction of the chloroform-methanol (1:1, v/v) extracts in order to remove D-mannitol. We then attempted to isolate antiangiogenic substances from the methanol-soluble fraction, which showed antitumor and antiangiogenic activities. We isolated two active substances (A-1 and A-2) from A. blazei with the aid of a Matrigel-induced angiogenesis assay system. This report describes the determination of the structure of A-1 and the effects of A-1 on tumor growth and lung metastasis in LLC-bearing mice. In addition, to clarify the mechanisms of the antitumor and antimetastatic activities of A-1, we examined the effects of A-1 on splenic immune function, tumor apoptosis and tumorinduced neovascularization. Materials and MethodsGeneral experimental procedures. The 1 H-NMR (499.83 MHz) and 13 C-NMR (125.68 Hz) spectra were recorded in D 2 O with a Varian Unity Inova 500 spectrometer (Tosoh, Tokyo). Mass spectra were measured with a Hitachi M-4000 H spectrometer (Tokyo). Thin layer chromatography (TLC), prepar...

Primary mechanism of apoptosis induction in a leukemia cell line by fraction FA-2-b-ß prepared from the mushroom Agaricus blazei Murill

“…In recent years, many studies have reported that different extracts of A. blazei Murill have various anticancer effects, ranging from the improvement of immune-modulatory activity (19)(20)(21) to the inhibition of tumor growth via direct inhibition of tumor-induced angiogenesis in mice (7). The results of the present study confirmed that fraction FA-2-b-ß did induce the apoptosis of HL-60 cells in vitro as indicated by morphological changes, DNA fragmentation and flow cytometry.…”

“…Research has indicated that the primary medical effect of A. blazei Murill is its anticancer activity in tumor-bearing mice (12). A. blazei Murill has been reported to be very effective against some malignancies, and possible explanations of its anticancer action have been proposed (2,3,7,8). The details of the mechanism, however, are still unclear.…”

Cultivable mushroom growth-promoting bacteria and their impact on Agaricus blazei productivity

“…Agaricus blazei contains active organic compounds associated with the maintenance of human health and the healing of diseases. Pharmacological studies have shown that bioactive substances, such as polysaccharide-protein complexes (PSPC) from A. blazei, function as antioxidants, antimutagenics, antitumorigenics, and anticancer agents (Kimura et al, 2004;Firenzuoli et al, 2008). However, the harvesting time of A. blazei is relatively long (approximately 60 days) when compared to other related Agaricus sp., including A. bisporus (approximately 30 days) (Pardo-Gimenez et al, 2010;Chu et al, 2012).…”

Inhibitory Effect ofAgaricu blazeiMurill Components on Abnormal Collagen Fiber Formation in Human Hepatocarcinoma Cells

“…It has been quite recently shown that pyroglutamate contained in Agaricus blazei inhibited tumor growth by in vivo experiments on tumor-implanted mice. 14) These results suggest that Agaricus blazei has strong potential as an alternative medicine.…”