Biomedical subjects

Betty Y Shih

Publications and source records attributed to Betty Y Shih.

5 recordsLinked to original sources

PubMed2006

Antiestrogenic glyceollins suppress human breast and ovarian carcinoma tumorigenesis.

PURPOSE: We have identified the phytoalexin compounds glyceollins I, II, and III, which exhibit marked antiestrogenic effects on estrogen receptor function and estrogen-dependent tumor growth in vivo. The purpose of this study was to investigate the interactions among the induced soy phytoalexins glyceollins I, II, and III on the growth of estrogen-dependent MCF-7 breast cancer and BG-1 ovarian cancer cells implanted in ovariectomized athymic mice. EXPERIMENTAL DESIGN: Four treatment groups for each cell line were used: vehicle control, 20 mg/kg/mouse/d glyceollin mixture injection, 0.72 mg estradiol (E2) implant, and E2 implant + 20 mg/kg/mouse/d glyceollin injection. RESULTS: Treatment with glyceollin suppressed E2-stimulated tumor growth of MCF-7 cells (-53.4%) and BG-1 cells (-73.1%) in ovariectomized athymic mice. These tumor-inhibiting effects corresponded with significantly lower E2-induced progesterone receptor expression in the tumors. In contrast to tamoxifen, the glyceollins had no estrogen-agonist effects on uterine morphology and partially antagonized the uterotropic effects of estrogen. CONCLUSIONS: These findings identify glyceollins as antiestrogenic agents that may be useful in the prevention or treatment of breast and ovarian carcinoma.

Animals↗

PubMed2005

Effect of soybean lipoxygenase on volatile generation and inhibition of Aspergillus flavus mycelial growth.

Volatiles generated from lipoxygenase (LOX) normal and LOX deficient soybean (Glycine max) varieties with and without added lipase inhibited Aspergillus flavus mycelial growth and aflatoxin production. Soybean volatiles were analyzed using a solid phase microextraction (SPME) method combined with gas chromatography-mass spectrometry (GC-MS). Twenty-one compounds, including 11 aldehydes, three alcohols, four ketones, one furan, one alkane, and one alkene were detected in the LOX normal soybean line. However, only nine volatile compounds were observed in the LOX deficient soybean variety. The antifungal aldehydes hexanal and (E)-2-hexenal were observed in both LOX normal and LOX deficient lines and were detected at significantly higher amounts in soybean homogenate with added lipase. These aldehydes may be formed through alternate pathways, other than the LOX pathway, and may account for the inhibition of A. flavus growth observed. Other volatiles detected, particularly the ketones and alcohols, may contribute to the antifungal activity observed in both LOX normal and LOX deficient soybean lines. These results suggest that other factors, other than LOX activity, may better explain why soybeans are generally not as severely affected by A. flavus and aflatoxin contamination as other oilseed crops.

Aflatoxins↗

PubMed2003

Identification of volatile compounds in soybean at various developmental stages using solid phase microextraction.

Soybean (Glycine max) seed volatiles were analyzed using a solid phase microextraction (SPME) method combined with gas chromatography-mass spectrometry (GC-MS). Thirty volatile compounds already reported for soybean were recovered, and an additional 19 compounds not previously reported were identified or tentatively identified. The SPME method was utilized to compare the volatile profile of soybean seed at three distinct stages of development. Most of the newly reported compounds in soybean seed were aldehydes and ketones. During early periods of development at maturity stage R6, several volatiles were present at relatively high concentrations, including 3-hexanone, (E)-2-hexenal, 1-hexanol, and 3-octanone. At maturity stage R7 and R8, decreased amounts of 3-hexanone, (E)-2-hexenal, 1-hexanol, and 3-octanone were observed. At maturity stage R8 hexanal, (E)-2-heptenal, (E)-2-octenal, ethanol, 1-hexanol, and 1-octen-3-ol were detected at relatively high concentrations. SPME offers the ability to differentiate between the three soybean developmental stages that yield both fundamental and practical information.

Aldehydes↗

PubMed2003

Evaluation of the estrogenic effects of legume extracts containing phytoestrogens.

Seven legume extracts containing phytoestrogens were analyzed for estrogenic activity. Methanol extracts were prepared from soybean (Glycine max L.), green bean (Phaseolus vulgaris L.), alfalfa sprout (Medicago sativa L.), mung bean sprout (Vigna radiata L.), kudzu root (Pueraria lobata L.), and red clover blossom and red clover sprout (Trifolium pratense L.). Extracts of kudzu root and red clover blossom showed significant competitive binding to estrogen receptor beta (ERbeta). Estrogenic activity was determined using an estrogen-dependent MCF-7 breast cancer cell proliferation assay. Kudzu root, red clover blossom and sprout, mung bean sprout, and alfalfa sprout extracts displayed increased cell proliferation above levels observed with estradiol. The pure estrogen antagonist, ICI 182,780, suppressed cell proliferation induced by the extracts, suggesting an ER-related signaling pathway was involved. The ER subtype-selective activities of legume extracts were examined using transiently transfected human embryonic kidney (HEK 293) cells. All seven of the extracts exhibited preferential agonist activity toward ERbeta. Using HPLC to collect fractions and MCF-7 cell proliferation, the active components in kudzu root extract were determined to be the isoflavones puerarin, daidzin, genistin, daidzein, and genistein. These results show that several legumes are a source of phytoestrogens with high levels of estrogenic activity.

Breast Neoplasms↗

PubMed2003

Identification of flavone aglycones and glycosides in soybean pods by liquid chromatography-tandem mass spectrometry.

High-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry was used to identify flavone aglycones and glycosides in soybean pods. Tandem mass spectrometry (MS-MS and MS-MS-MS) and photodiode array detection were also utilized in flavone characterization. A total of seven flavone aglycones and glycosides were identified. Among them three flavone aglycones--apigenin, 7,4'-dihydroxyflavone, and luteolin--and two flavone glycosides--apigenin-7-O-beta-D-glucoside, and luteolin-7-O-beta-D-glucoside--were unambiguously identified based on their abundant (M+H)+ ions, UV spectra, retention time, and tandem mass spectrometric analysis compared with authentic standards. The tentative identification of two flavone glycosides as 7,4'-dihydroxyflavone-7-O-beta-D-glucoside and apigenin-7-O-beta-D-glucoside-6"-O-malonate was based on UV spectra, (M+H)+ ions, and tandem mass spectrometry. This is the first report identifying flavone aglycones and glycosides in soybean pods.

Apigenin↗