Showing papers by "Nianbai Fang published in 2006"
TL;DR: There were significant interspecies differences in isoflavone metabolism, and the overall metabolic profile of pigs was closer to that of women than that of rats or monkeys.
Abstract: Various physiologic effects of soy food consumption have been attributed to the estrogenic actions of isoflavones. The order of estrogen receptor binding potency of soy-derived isoflavone aglycones is equol > genistein > daidzein, and their conjugates are less potent. Because the metabolic profile may be an important determinant of bioactivity after soy intake, we studied the serum and urine isoflavone concentrations in 3 animal models and compared them with isoflavone profiles in women. Female Sprague-Dawley rats, Hampshire/Duroc Cross pigs, cynomolgus monkeys, and women were fed diets containing soy protein isolate. Isoflavones and their metabolites were measured by LC-MS or electrochemical detection. Equol represented approximately 77 and 52% (molar ratio) of summed serum isoflavones (isoflavones plus metabolites) in rats and cynomolgus monkeys, respectively. Equol was undetectable in pig serum and human plasma, but daidzein and genistein contributed >88% of summed circulating isoflavones. Monkey and rat urine contained high levels of aglycones (>85% and >32%, respectively), whereas pigs and women excreted isoflavone mainly in the form of glucuronides (>80%), with <10% as aglycones. Isoflavones in human plasma were predominantly glucuronides (75%) with 24% as sulfates and <1% as aglycones; in monkey serum, however, 64% of isoflavones were sulfates, 30% glucuronides, and 6% aglycones. Equol was also a major serum metabolite of 6-mo-old rhesus monkeys (80% of summed isoflavones). Thus, there were significant interspecies differences in isoflavone metabolism, and the overall metabolic profile of pigs was closer to that of women than that of rats or monkeys.
187 citations
TL;DR: Data suggest that inhibition of growth in tumor cells by "mycochemicals" in shiitake mushrooms may result from induction of apoptosis.
Abstract: Objective: Shiitake (Lentinus edodes) mushrooms have been reported to have cancer-preventing properties. However, little research has been conducted verifying the antitumor activities of "mycochemicals" in shiitake mushrooms. In this study, potential roles of an ethyl acetate fraction from shiitake mushrooms were investigated by in vitro bioassays. Design: The activities of an ethyl acetate fraction were evaluated by [3-(4,5-dimethylthiazol-yl)-2,5-diphenyltetrazolium bromide] (MTT), apoptosis bioassay, cell cycle analysis, and Western blot analysis using two human breast carcinoma cell lines (MDA-MB-453 and MCF-7), one human nonmalignant breast epithelial cell line (MCF-10F), and two myeloma cell lines (RPMI-8226 and IM-9). Results: Concentration-dependent antiproliferative effects of the fraction were observed in all cell lines using the MTT assay. Approximately 50 mg/L concentration of the fraction induced apoptosis in 50% of the population of four human tumor cell lines and the fraction-induced apopto...
57 citations
TL;DR: In vitro antitumor activities of an ether fraction from RPI was studied using human tumor cell lines, including two human breast carcinoma cell lines (MDA-MB-453 and MCF-7) and two myeloma cell Lines (RPMI-8226 and IM-9).
Abstract: Rice protein isolate (RPI) has been reported to reduce the incidence of 7,12-dimethylbenz[a]anthracene-induced mammary tumors in rats. To determine the potential role of phytochemicals associated with the RPI, we studied in vitro antitumor activities of an ether fraction from RPI using human tumor cell lines, including two human breast carcinoma cell lines (MDA-MB-453 and MCF-7) and two myeloma cell lines (RPMI-8226 and IM-9). Concentration-dependent antiproliferative effects of the ether fraction were observed in all cell lines using the standard 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. Fraction-induced apoptosis (P < 0.05) was detected in all cell lines, and this was associated with the induction of proapoptotic bax protein and cdk inhibitors (p21) and the suppression of cdk4 and cyclin D1 activity. Liquid chromatography−mass spectrometry/mass spectrometry (LC-MS/MS) with both positive and negative modes was used to analyze the phytochemicals in the ether fraction from RPI. Fi...
15 citations
TL;DR: Results demonstrate stimulatory actions of 1% and inhibitory actions of 4% Shiitake mushroom on indices of rat colon tumorigenesis, which may be associated with altered metabolism.
11 citations