irisolidone and tectorigenin

Tectorigenin (Te) is a main active component in the flowers of Pueraria thomsonii Benth. and the rhizomes of Belamcanda chinensis (L.) DC. Previously, we have reported the pharmacokinetic properties of Te in rat plasma. The purpose of this study was to investigate the urinary excretion of Te after oral administration to rats at different dose levels. Using UHPLC/Q-TOFMS, totally 26 metabolites were detected in rat urine after oral administration of Te at dose of 65 and 130 mg/kg. Among them, nine metabolites, Te, tectorigenin-7-O-glucuronide-4'-sulfate (Te-7G-4'S), tectorigenin-7-O-glucuronide (Te-7G), tectorigenin-7-O-sulfate (Te-7S), tectorigenin-4'-O-glucuronide (Te-4'S), isotectorigenin, genistein, irisolidone-7-O-glucuronide (Ir-7G), and irisolidone, were identified by comparing the retention time, UV and MS spectra with those of authentic standards. A UHPLC/Q-TOFMS method for simultaneous quantification and semi-quantification of all the metabolites in urine was developed. The cumulative urinary excretions of Te and the major metabolite Te-7G were 1.99 and 5.80 μmol at 65 mg/kg, 3.05 and 6.48 μmol at 130 mg/kg, accounted for 4.17 % and 15.8, 2.81 and 9.49 % of administrated Te, respectively. The excretion rates of Te-7G, Te-7G-4'S, Ir-7G, and Te reached a maximum between 12 and 24 h after oral dosing at 65 and 130 mg/kg. The cumulative urine excretion rates of Te were 23.1 and 20.1 % within 72 h at 65 and 130 mg/kg, respectively. These results suggested that the glucuronidation was the primary metabolic pathway especially at low dose level.

Topics: Administration, Oral; Animals; Chromatography, High Pressure Liquid; Flavonoids; Genistein; Glucuronides; Isoflavones; Male; Mass Spectrometry; Pueraria; Rats; Rats, Sprague-Dawley; Rhizome

This study investigated the metabolic fate of kakkalide (irisolidone 7-xylosylglucoside), a major isoflavone found in extracts of Pueraria lobata flowers, and in rat urine, bile, and feces. Using HPLC/UV or LC/MS/MS methods, seven metabolites, tectorigenin-7-O-glucuronide, tectorigenin-7-O-sulfate, tectorigenin-4'-O-sulfate, 6-OH biochanin A-glucuronide, irisolidone-7-O-glucuronide, tectorigenin, and irisolidone were identified in rat urine after oral administration of kakkalide. Furthermore, irisolidone-7-O-glucuronide was found in bile, and irisolidone and kakkalide were found in feces. An HPLC/UV method for simultaneous quantification of all the metabolites and kakkalide in urine, bile, and feces was developed using daidzein or apigenin as the internal standard. Over a 72-h period, 13.2 ± 2.8 % of the kakkalide was excreted as seven metabolites in urine. Over the same time period, irisolidone-7-O-glucuronide excretion in bile accounted for 3.8 ± 1.1 % of the dose, while kakkalide and irisolidone excretion in feces accounted for 2.1 ± 0.7 % and 0.7 ± 0.1 % of the dose, respectively. The results indicate that urine is the primary route of kakkalide elimination in vivo and that extensive metabolism may be one of the reasons for the low bioavailability of kakkalide.

Topics: Administration, Oral; Animals; Bile; Chromatography, High Pressure Liquid; Chromatography, Liquid; Feces; Flavonoids; Glycosides; Isoflavones; Male; Pueraria; Rats; Rats, Wistar; Tandem Mass Spectrometry

To understand the relationship between the metabolism and estrogenic activity of kakkalide and tectoridin, main isoflavones in the flower of Pueraria thunbergiana (family Leguminosae), these isoflavones and their metabolites by human intestinal microflora as well as their estrogenic effects were investigated. All human fecal specimens metabolized kakkalide and tectoridin. All isolated kakkalide-hydrolyzing intestinal bacteria also hydrolyzed kakkalide and tectoridin to irisolidone and tectorigenin, respectively. When the estrogenic effects of kakkalide and tectoridin were compared with those of their metabolites irisolidone and tectorigenin, the metabolites more potently increased proliferation of MCF-7 cells than kakkalide and tectoridin. These metabolites also potently induced estrogen-response c-fos and pS2 mRNA expression. These results suggest that kakkalide and tectoridin may be metabolized mainly to irisolidone and tectorigenin, respectively, by intestinal microflora in the intestines, and which may be subsequently absorbed into the blood where they can express their estrogenic effect.

Topics: Adult; Bifidobacterium; Cell Line, Tumor; Cell Proliferation; Feces; Flavonoids; Flowers; Glycosides; Humans; Intestines; Isoflavones; Male; Phytoestrogens; Pueraria; Substrate Specificity; Xylosidases; Young Adult

The inhibitory effect of isoflavones isolated from the flowers and rhizomes of Pueraria thunbergiana (Leguminosae) on the growth of Helicobacter pylori (HP) was investigated. Isoflavone glycosides did not inhibit the growth of HP. However, their aglycones, irisolidone, tectorigenin and genistein, inhibited HP growth. Among them, irisolidone had the most potent inhibitory activity against HP and its MIC was 12.5-25 micrograms/ml. Genistein only weakly inhibited the urease of HP and H+/K(+)-ATPase of rat stomach: its IC50 were 0.43 and 0.89 mg/ml, respectively.

Topics: Animals; Anti-Bacterial Agents; Fabaceae; Flavonoids; Gastric Mucosa; Genistein; Helicobacter pylori; Isoflavones; Male; Microbial Sensitivity Tests; Plants, Medicinal; Proton-Translocating ATPases; Rats; Urease