Pueraria thomsonii has long been used in traditional Chinese medicine. Isoflavonoids are the principle pharmacologically active components, which are primarily observed as glycosyl-conjugates and accumulate in P. thomsonii roots. However, the molecular mechanisms underlying the glycosylation processes in (iso)flavonoid biosynthesis have not been thoroughly elucidated. In the current study, an O-glucosyltransferase (PtUGT8) was identified in the medicinal plant P. thomsonii from RNA-seq database. Biochemical assays of the recombinant PtUGT8 showed that it was able to glycosylate chalcone (isoliquiritigenin) at the 4-OH position and glycosylate isoflavones (daidzein, formononetin, and genistein) at the 7-OH or 4'-OH position, exhibiting no enzyme activity to flavonones (liquiritigenin and narigenin) in vitro. The identification of PtUGT8 may provide a useful enzyme catalyst for efficient biotransformation of isoflavones and other natural products for food or pharmacological applications.
Cloning, Molecular ; Genistein ; Glucosyltransferases/metabolism* ; Isoflavones/pharmacology* ; Pueraria/chemistry*

OBJECTIVE: To investigate the inhibitory effect of genistein on activation of hepatic stellate cells (HSCs) and the role of the autophagy pathway regulated by PPAR-γ in mediating this effect. METHODS: Cultured HSC-T6 cells were exposed to different concentrations of genistein for 48 h, and HSC activation was verified by detecting the expressions of -SMA and 1(I) collagen; autophagy activation in the cells was determined by detecting the expressions of LC3-II and p62 using Western blotting. The autophagy inhibitor 3-MA was used to confirm the role of autophagy in genistein-induced inhibition of HSC activation. A PPAR-γ inhibitor was used to explore the role of PPAR-γ in activating autophagy in the HSCs. RESULTS: Genistein at concentrations of 5 and 50 μmol/L significantly inhibited the expressions of -SMA and 1(I) collagen ( < 0.05), markedly upregulated the expressions of PPAR-γ and the autophagy-related protein LC3-II ( < 0.05) and significantly down-regulated the expression of the ubiqutin-binding protein p62 ( < 0.05) in HSC-T6 cells. The cells pretreated with 3-MA prior to genistein treatment showed significantly increased protein expressions of -SMA and 1(I) collagen compared with the cells treated with genistein only ( < 0.05). Treatment with the PPAR-γ inhibitor obviously lowered the expression of LC3-II and enhanced the expression p62 in genistein-treated HSC-T6 cells, suggesting the activation of the autophagy pathway. CONCLUSIONS PPAR-γ- regulated autophagy plays an important role in mediating genistein-induced inhibition of HSC activation .
Anticarcinogenic Agents ; pharmacology ; Autophagy ; Collagen Type I ; Genistein ; pharmacology ; Hepatic Stellate Cells ; Humans ; PPAR gamma ; physiology

Twelve flavonoids were isolated and purified from the ethyl acetate fraction of 95% ethanol extract of Dalbergia odorifera by heat reflux extraction, solvent extraction, recrystallization, normal phase silica gel, Sephadex LH-20, MCI gel and HPLC methods. The structures were identified with multiple spectroscopic methods, including 1 D-NMR, 2 D-NMR and MS. The compounds were identified as 6,7,8-trimethoxy-5,4'-dihydroxy isoflavone(1), medicarpin(2), 7,2'-dihydroxy-4'-methoxy-isoflavanol(3), biochanin A(4), prunetin(5), genistein(6), pratensein(7), 3-(4-hydroxyphenyl)-6-isopentenyl-7-methoxy-4H-chromen-4-one(8), tectorigenin(9), irisolidone(10), vestitol(11), and formononetin(12). Compound 1 was a new isoflavone, and compound 8 was isolated from D. odorifera for the first time. The results showed that compounds 1-3 had inhibitory effects on tyrosinase, with inhibition rates of 35.58%, 38.63% and 51.34% at the concentration of 1.0 mmol·L~(-1), respectively.
Dalbergia/chemistry* ; Ethanol ; Flavonoids/chemistry* ; Genistein ; Isoflavones/pharmacology* ; Monophenol Monooxygenase ; Plant Extracts/pharmacology* ; Silica Gel ; Solvents

Genistein is a high specific and noncompetitive inhibitor of epidermal growth factor receptor tyramine kinase domain (EGFR-TK). In the paper, a molecular docking between genistein and EGFR-TK was studied to explore the mechanism of their interaction and antitumor mechanism of genistein by AUTODOCK 3.05 program. The results indicated that genistein located in the active cavity of EGFR-TK by high affinity (deltaG = -31.2 kJ/mol), and genistein inhibited EGFR-TK by interfering with forming of Lys721/Glu738 ion pair. The inhibition belonged to noncompetitive interaction, in which hydrophobic force and hydrogen bond played key roles.
Catalytic Domain ; Genistein ; metabolism ; pharmacology ; Models, Molecular ; Receptor, Epidermal Growth Factor ; antagonists & inhibitors ; metabolism

Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Genistein ; pharmacology ; Humans ; Nasopharyngeal Neoplasms ; pathology

The chemical constituents from the branches and leaves of Artocarpus incisus were isolated and purified via silica gel, ODS, and Sephadex LH-20 column chromatography as well as preparative HPLC. The chemical structures of all isolated compounds were identified in the light of their physicochemical properties, spectroscopic analyses, and comparisons of their physicochemical and spectroscopic data with the reported data in literature. As a result, 20 compounds were isolated and characterized from the 90% ethanol extract of the branches and leaves of A. incisus, which were identified as tephrosin(1), 6-hydroxy-6 a, 12 a-dehydrodeguelin(2), sarcolobin(3), lupiwighteone(4), 12-deoxo-12α-methoxyelliptone(5), 6 aα,12 aα-12 a-hydroxyelliptone(6), homopterocarpin(7), 3-hydroxy-8,9-dimethoxypterocarpan(8), pterocarpin(9), maackiain(10), medicarpin(11), calycosin(12), genistein(13), formononetin(14), 5-hydroxy-4',7-dimethoxy isoflavone(15), liquiritigenin(16), 4(15)-eudesmene-1β,7α-diol(17), ent-4(15)-eudesmene-1β,6α-diol(18), 1α-hydroxyisodauc-4-en-15-al(19), and guaianediol(20). Except compounds 13 and 16, all other compounds were isolated from the Artocarpus plants for the first time. Additionally, using MTS assay, compounds 1-20 were eva-luated for their anti-rheumatoid arthritis activities by measuring their anti-proliferative effects on synoviocytes in vitro. As a consequence, compounds 1-16 showed notable anti-rheumatoid arthritis activities, which displayed inhibitory effects on the proliferation of MH7 A synovial fibroblast cells, with the IC_(50) values in range of(9.86±0.09)-(218.07±1.96) μmol·L~(-1).
Arthritis ; Artocarpus ; Cell Proliferation ; Ethanol ; Genistein ; Plant Extracts/pharmacology* ; Silica Gel ; Synoviocytes

Antineoplastic Agents ; pharmacology ; Carcinoma, Hepatocellular ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Genistein ; pharmacology ; Humans ; Liver Neoplasms ; pathology ; Oncogenes

OBJECTIVEGenistein, a major soy isoflavone metabolite (SIF), inactivates oxidation activity of bovine lactoperoxidase (LPO). Modification of the heme moiety of LPO by nitrogen-containing compounds has been shown to inactivate LPO. In contrast, SIF mediated inactivation of LPO does not involve a heme modification and the mechanism of SIF inhibition is poorly understood.

METHODSAfter inactivation of LPO by genistein in the presence of H(2)O(2), trypsin-digested LPO peptide fragments were collected and analyzed by MALDI-TOF-MS to characterize the chemical binding of genistein(s) to LPO.

RESULTSThe heme moiety of LPO was not modified by genistein. A covalent binding study showed that (3)H-genistein bound to LPO with a ratio of ∼12 to 1. After HPLC analysis and peak collection, trypsin-digested peptide fragments were analyzed by MALDI-TOF-MS. The 3H-genistein co-eluted peptide fragments (RT=24 min) were putatively identified as 199IVGYLDEEGVLDQNR214 with two bound genistein molecules or a genistein dimer (2 259 Da), 486TPDNIDIWIGGNAEPMVER504 with two bound genistein molecules or a genistein dimer (2 663 Da), and 161ARWLPAEYEDGLALPFGWTQR182 with three bound genistein molecules or a genistein trimer (3 060 Da). The fragment with a mass of 1 792 Da (RT=36 min) was identified as 132CDENSPYR139 with three genistein molecules or a genistein trimer.

CONCLUSIONSThe results suggest that LPO was inactivated by irreversible covalent binding of genistein or genistein polymers to particular peptide fragments constituting regions of the outward domain. No genistein interaction with the prosthetic heme moiety of LPO was observed.

Animals ; Cattle ; Enzyme Activation ; drug effects ; Genistein ; metabolism ; Hydrogen Peroxide ; pharmacology ; Isoflavones ; pharmacology ; Lactoperoxidase ; metabolism ; Placental Lactogen ; Protein Binding

Animals ; Cell Cycle ; drug effects ; Enzyme Inhibitors ; pharmacology ; Genistein ; pharmacology ; Liver ; cytology ; drug effects ; Male ; Rats ; Rats, Wistar

The purpose of this study was to investigate the effects of phytoestrogen genistein (GST) on delayed after depolarization (DAD) and triggered activity (TA) induced by ouabain in guinea pig papillary muscles. Action potentials (APs) were recorded from the guinea pig papillary muscles with standard glass microelectrode technique. The results are as follows: (1) DAD and TA induced by ouabain (1 micromol/L) were markedly inhibited by pretreatment with GST (10, 50, 100 micromol/L) in a concentration-dependent manner. (2) NG-nitro-L-arginine methyl ester (L-NAME, 1 mmol/L), an NO synthase inhibitor, failed to affect the above effects of GST. (3) 5 micromol/L 17beta-estradiol (E2) or 10 micromol/L GST alone showed no effects on DAD and TA, whereas GST combined with E(2) at the same doses exerted significant inhibitory effects on DAD and TA. Since GST is known to reduce the calcium influx, it is suggested that GST might have antiarrhythmic effects, possibly by reducing calcium influx. The antiarrhythmic effects of GST may contribute to its cardioprotective action.
Action Potentials ; drug effects ; Animals ; Genistein ; pharmacology ; Guinea Pigs ; Male ; Neuromuscular Depolarizing Agents ; pharmacology ; Ouabain ; pharmacology ; Papillary Muscles ; drug effects ; physiology ; Phytoestrogens ; pharmacology