The Basidiomycete fungus Agaricus blazei Murill has traditionally been used as a health food for the prevention of cancer, diabetes, hyperlipidemia, arteriosclerosis and chronic hepatitis. In the present study, we examined the antitumor activities of various substances isolated from the lipid fraction of A. blazei. Tumor growth was retarded by the oral administration of the lipid fraction extracted from A. blazei with a chloroform/methanol mixture in sarcoma 180-bearing mice. The substance with the antitumor activity in the lipid fraction was isolated via silica gel column chromatography, eluted with an acetonitrile/methanol (3:2) mixture and identified as ergosterol by direct comparison of the (1)H NMR and mass spectrometry spectral data of an authentic sample. The oral administration of ergosterol to sarcoma 180-bearing mice significantly reduced tumor growth at doses of 400 and 800 mg/kg administered for 20 d without side effects, such as the decreases in body, epididymal adipose tissue, thymus, and spleen weights and leukocyte numbers induced by cancer chemotherapy drugs. Ergosterol had no cytotoxicity against tumor cells. To clarify the antitumor activity of ergosterol, we examined the effects of ergosterol on tumor-induced angiogenesis using two in vivo models. Intraperitoneal administration of ergosterol at doses of 5, 10 and 20 mg/kg for 5 consecutive d inhibited the neovascularization induced by Lewis lung carcinoma cell-packed chambers, suggesting that either ergosterol or its metabolites may be involved in the inhibition of tumor-induced neovascularization. Therefore, we further examined the inhibitory effects of ergosterol on Matrigel-induced neovascularization. Female C57BL/6 mice were subcutaneously inoculated with Matrigel containing acidic fibroblast growth factor and heparin with or without ergosterol. Ergosterol inhibited the Matrigel-induced neovascularization, suggesting that ergosterol directly inhibits Matrigel-induced neovascularization. From these results, it seems likely that the antitumor activity of ergosterol might be due to direct inhibition of angiogenesis induced by solid tumors. This is the first report of ergosterol as an antiangiogenic substance.

OBJECTIVE: Oolong tea is traditionally reported to have anti-obesity and hypolipidaemic effects. The present study was performed to clarify whether oolong tea prevented obesity induced in mice by the oral administration of a highfat diet for 10 weeks. DESIGN: High-fat diet-induced obese mice were treated with oolong tea for 10 weeks. The effects of various active fractions isolated from oolong tea on noradrenaline-induced lipolysis were examined with isolated fat cells and a cellfree system consisting of lipid droplets and hormone-sensitive lipase (HSL). RESULTS: The mean food consumption was not signi®cantly different between high-fat diet-treated mice and high-fat plus oolong tea diet-treated mice. Oolong tea prevented the obesity and fatty liver induced by a high-fat diet. A water extract of oolong tea enhanced noradrenaline-induced lipolysis, and the active substance was identi®ed as caffeine. Caffeine enhanced noradrenaline-induced lipolysis in fat cells without a concomitant increase in HSL activity and also accelerated the hormone-induced lipolysis in a cell-free system consisting of lipid droplets and HSL, but not in the cellfree system with sonicated lipid droplets and HSL. Oolong tea extract inhibited pancreatic lipase activity. CONCLUSION: It was demonstrated that the anti-obesity effects of oolong tea in high-fat diet-treated mice might be due partly to the enhancing effect of caffeine isolated from oolong tea on noradrenaline-induced lipolysis in adipose tissue, and to the inhibitory action of some other substance in oolong tea on pancreatic lipase activity. Caffeine was found to enhance lipolysis through acting on lipid droplets but not on HSL. The results suggest that oolong tea may be an effective crude drug for the treatment of obesity and fatty liver caused by a high-fat diet.

OBJECTIVE: Based on the inhibitory effects of teasaponin on pancreatic lipase activity in vitro, this study was performed to clarify whether teasaponin prevented obesity induced in mice by a high-fat diet for 11 weeks. DESIGN: For in vitro experiments, assay for the inhibitory effects of teasaponin on pancreatic lipase activity was performed by measuring the rate of release of oleic acid from triolein in an assay system using triolein emulsified with lecithin, gum arabic, Triton X-100 or 4-methylumbelliferyloleate. For in vivo experiments, female ICR mice were fed a high-fat diet with or without 0.5% teasaponin for 11 weeks. RESULTS: Teasaponin competitively inhibited the hydrolysis of triolein emulsified with lecithin, gum arabic, Triton X-100 or 4-methylumbelliferyloleate. Teasaponin inhibited the elevations of plasma triacylglycerol levels 3, 4 and 5 h after oral administration of lipid emulsion containing corn oil. Teasaponin suppressed the increases in body, parametrial adipose tissue weights and diameter in adipose cell size induced by a high-fat diet. Furthermore, feeding a high-fat diet plus teasaponin had no effect on stool frequency and content, but significantly increased triacylglycerol contents in feces as compared to feeding a high-fat diet. CONCLUSIONS: The anti-obesity effects of teasaponin in high-fat diet-treated mice may be partly mediated through delaying the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity.

The leaves of the persimmon Diospyros kaki, have been traditionally used for treatment of hypertensive diseases in Japan. We have studied the inhibitory effects of four flavonoids isolated from the leaves of the persimmon on angiotensin-converting enzyme activity. The four flavonoids astragalin [1], kaempferol-3-O-(2"-O-galloyl)-glucoside [2], isoquercitrin [3], and quercetin-3-O-(2"-O-galloyl)-glucoside [4] inhibited the angiotensin-converting enzyme activity in a dose-dependent fashion. Compounds 1-4 produced 67%, 53%, 33%, and 48% inhibition at a concentration of 300 micrograms/ml, respectively. The 50% inhibitory concentrations (IC50) of 1 and 2 for the angiotensin-converting enzyme were 180 micrograms/ml and 280 micrograms/ml, respectively. On the other hand, 2 and 4 were shown to have tannin activities, but 1 and 3 had no tannin activities. These results suggest that there is no relationship between the inhibition for angiotensin converting enzyme activity and the tannin activity for the four flavonoids.

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...