New 8,12;8,20-diepoxy-8,14-secopregnane hexa- and hepta-glycosides from the roots of Asclepias tuberosa.

Previously, phytochemical investigation of the roots of Asclepias tuberosa (Asclepiadaceae) led to the isolation of some 8,12;8,20-diepoxy-8,14-secopregnane tri-, tetra-, and penta-glycosides. An additional eight new minor 8,12;8,20-diepoxy-8,14-secopregnane glycosides were afforded in the recent investigation of this plant. These glycosides consisted of six or seven 2,6-dideoxy-hexopyranoses together with the aglycone, tuberogenin. The structures of each of these compounds were established using NMR, mass spectroscopic analysis and chemical evidence. As 8,12;8,20-diepoxy-8,14-secopregnane-type glycosides were observed only in A. tuberosa, these compounds were considered to be characteristic phytochemicals of this plant.

Flavonoid Glycosides from Sedum bulbiferum.

The MeOH extract from dried whole Sedum bulbiferum MAKINO (Crassulaceae) plants yielded 34 compounds, including six new flavonoid glycosides and 28 known compounds. The structures of new compounds were established using NMR, Mass spectroscopic analysis and chemical evidence.

Chemical constituents of aerial parts and roots of Pycnanthemum flexuosum.

An extract of whole plants of Pycnanthemum flexuosum showed an inhibitory effect on hyaluronidase activity. From an 80% acetone extract of aerial parts, 3-[(3E)-4-phenylbut-3-enoylamino]propionic acid, 3-O-ß-D-glucuronopyranosyl-echinocystic acid 28-O-ß-D-xylopyranosyl-(1→3)-[3,4-diacetyl-ß-D-xylopyranosyl-(1→4)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester, vanillic acid 1-O-[(5-O-syringoyl)-ß-D-apiofuranosyl]-(1→2)-ß-D-glucopyranoside, and (4S,5R)-4-hydroxy-5-phenyl-tetrahydrofuran-2-one were isolated together with 30 known compounds. Six known compounds were isolated from an 80% acetone extract of roots, and eritrichin was revealed as a hyaluronidase inhibitor in P. flexuosum.

Diastereomers of lithospermic acid and lithospermic acid B from Monarda fistulosa and Lithospermum erythrorhizon.

Monardic acids A (1) and B (2), which are (7R,8R) diastereomers of lithospermic acid (LA) and lithospermic acid B, respectively, were isolated from Monarda fistulosa. A (7S,8R) isomer (3) of LA was also isolated from this plant, and a (7R,8S) isomer (7) of LA was obtained from Lithospermum erythrorhizon. The absolute configuration of 1 was confirmed by analysis of its hydrolysates, 7-epiblechnic acid and 2R-3-(3,4-dihydroxyphenyl)-2-hydroxypropanoic acid. The configuration in the dihydrobenzofuran moieties of 2, 3, and 7 was extrapolated by using the phenylglycine methyl ester method and a Cotton effect at approximately 250-260 nm in their electronic circular dichroism spectra. Diastereomers (1-3 and 7) displayed moderate hyaluronidase inhibitory and histamine release inhibitory activities.

Hydroxylation of (-)-epigallocatechin-3-O-gallate at 3'', but not 4'', is essential for the PI3-kinase/Akt-dependent phosphorylation of endothelial NO synthase in endothelial cells and relaxation of coronary artery rings.

(-)-Epigallocatechin-3-O-gallate (EGCg) has been shown to induce endothelium-dependent nitric oxide (NO)-mediated relaxation via the redox-sensitive Src/PI3-kinase/Akt-dependent phosphorylation of endothelial NO synthase (eNOS). Although the presence of 8 hydroxyl functions, mainly on B and D rings, is essential for the EGCg-induced activation of eNOS, the relative role of each individual hydroxyl function still remains unclear. This study examined the effect of selective replacement of hydroxyl functions by methoxy moieties on either the B or D ring on the EGCg-induced phosphorylation of Akt and eNOS, formation of reactive oxygen species (ROS) and NO in cultured coronary artery endothelial cells, and endothelium-dependent relaxation of coronary artery rings. Replacement of a single hydroxyl by the methoxy group on position 3', 4' or 4'' affected little the EGCg-induced phosphorylation of Akt and eNOS, formation of ROS and NO in endothelial cells, and induction of endothelium-dependent relaxations. In contrast, the single methylation at position 3'' and the double methylation at both positions 3' and 4' reduced markedly the phosphorylation of Akt and eNOS, the formation of ROS and NO in endothelial cells and the relaxation of artery rings. These findings suggest that the hydroxyl group at the 3'' position of the gallate ring is essential and, also, to some extent, the two hydroxyl groups at positions 3' and 4', for the EGCg-induced redox-sensitive activation of eNOS leading to the subsequent NO-mediated vascular relaxation.

Lipase inhibitory and LDL anti-oxidative triterpenes from Abies sibirica.

A methanol extract of Abies sibirica Ladeb, a Mongolian medicinal plant, had an inhibitory effect on both lipase activity in mouse plasma and LDL anti-oxidative activity, which are preventative factors for arteriosclerosis. The extract was fractionated by silica gel column chromatography and its active constituents were sought. From lipid soluble fractions, 20 terpenoids including seven hitherto unknown triterpenes were isolated. The latter triterpenes had either a γ-lactone ring with a lactol or a derivative thereof. Their chemical structures were determined by spectroscopic methods. The lipase inhibitory activity and LDL anti-oxidative activity of these compounds were evaluated. Some constituents (either lipase inhibitory or LDL anti-oxidative activities) had moderate inhibitory activities.

Flavonoid glycosides from Botrychium ternatum.

The MeOH extract from dried whole Botrychium ternatum plants yielded 33 compounds, including seventeen new flavonoid glycosides and sixteen known compounds. The structures of new compounds were established using NMR spectroscopic analysis and chemical evidence.

Triterpene saponins from the pericarps of Akebia trifoliata.

Eleven new triterpene saponin components (1-11) were isolated from the MeOH extract of pericarp of Akebia trifoliata (THUNB.) KOIDZ. Each of their structures was determined using NMR techniques and mass spectrometry.

Triterpene saponins with hyaluronidase inhibitory activity from the seeds of Camellia sinensis.

The MeOH extract of the seeds of Camellia sinensis (L.) KUNTZE gave twelve new saponins (1-12) along with ten known saponins (13-22). These saponins (1-22) showed stronger hyaluronidase inhibitory activity than the positive control, rosmarinic acid.

Constituents from the roots of Taraxacum platycarpum and their effect on proliferation of human skin fibroblasts.

A MeOH extract from the roots of Taraxacum platycarpum has shown significant effects on the proliferation of normal human skin fibroblasts. Chemical analysis of the extract resulted in the isolation of 26 compounds, including eight new triterpenes, one new sesquiterpene glycoside, and seventeen known compounds. The structure of each new compound was established using NMR spectroscopy. Some triterpenes had a significant effect on the proliferation of normal human skin fibroblasts.

Hyaluronidase inhibitors from Keiskea japonica.

An extract of Keiskea japonica MIQ. showed an inhibitory effect on hyaluronidase activity. From the extract, four new phenylpropanoids, two new maltol glycosides, two new monoterpene glycosides, and two new phenolic compounds were isolated together with 19 known compounds. Among these constituents, two phenylpropanoids and a flavone glucuronide were revealed as hyaluronidase inhibitors.

8,12;8,20-diepoxy-8,14-secopregnane glycosides from roots of Asclepias tuberosa and their effect on proliferation of human skin fibroblasts.

A pregnane glycoside fraction from the roots of Asclepias tuberosa L. caused normal human skin fibroblasts to proliferate. This fraction contained 21 pregnane glycosides whose structures were established using NMR spectroscopic analysis and chemical evidence. The aglycones of most of these compounds were identified as 8,12;8,20-diepoxy-8,14-secopregnanes, such as tuberogenin or 5,6-didehydrotuberogenin, the same aglycones as constituents of the aerial parts of this plant. Some of these compounds also caused proliferation of skin fibroblasts.

Estrogenic and anti-estrogenic compounds from the Thai medicinal plant, Smilax corbularia (Smilacaceae).

From the rhizomes of Smilax corbularia Kunth. (Smilacaceae), 11 compounds, (2R,3R)-2″-acetyl astilbin, (2R,3R)-3″-acetyl astilbin, (2R,3R)-4″-acetyl astilbin, (2R,3R)-3″-acetyl engeletin, (2R,3S)-4″-acetyl isoastilbin, 2-(4-hydroxyphenyl)-3,4,9,10-tetrahydro-3,5-dihydroxy-10-(3,4-dihydroxyphenyl)-(2R,3R,10R)-2H,8H-benzo [1,2-b:3,4-b'] dipyran-8-one, 2-(4-hydroxyphenyl)-3,4,9,10-tetrahydro-3,5-dihydroxy-10-(3,4-dihydroxyphenyl)-(2R,3R,10S)-2H, 8H-benzo [1,2-b:3,4-b'] dipyran-8-one, 3,4-dihydro-7-hydroxy-4-(3,4-dihydroxyphenyl)-5-[(1E)-2-(4-hydroxyphenyl) ethenyl]-2H-1-benzopyran-2-one, 3,4-dihydro-7-hydroxy-4-(3,4-dihydroxy-phenyl)-5-[(1E)-2-(3,4-dihydroxyphenyl) ethenyl]-2H-1-benzopyran-2-one, 3,4-dihydro-7-hydroxy-4-(4-hydroxy-3-methoxyphenyl)-5-[(1E)-2-(4-hydroxyphenyl) ethenyl]-2H-1-benzopyran-2-one, and 5,7,3',4'-tetrahydroxy-3-phenylcoumarin along with 34 known compounds were isolated and characterized as 19 flavonoids, 14 catechin derivatives, 6 stilbene derivatives, and 6 miscellaneous substances. All isolates had their estrogenic and anti-estrogenic activities determined using the estrogen-responsive human breast cancer cell lines MCF-7 and T47D. The major constituents were recognized as flavanonol rhamnosides by the suppressive effect on estradiol induced cell proliferation at a concentration of 1µM. Meanwhile, flavanonol rhamnoside acetates demonstrated estrogenic activity in both MCF-7 and T47D cells at a concentration of 100µM, and they enhanced the effects of co-treated E2 on T47D cell proliferation at concentrations of more than 0.1µM.

New phenolic compounds from Meehania urticifolia.

A new phenylethanoid glycoside, rashomoside A (1), a new phenolic glucoside, rashomoside B (2), and a new shikimic acid derivative (3) were isolated from Meehania urticifolia together with 12 known flavones (4-15), three known phenylethanoid glycosides (16-18), and 13 other compounds (19-31). The structure of each of these compounds was elucidated based on the results of spectroscopic analysis.

Preventive effects of C-2 epimeric isomers of tea catechins on mouse type I allergy.

The preventive effects of C-2 epimeric isomers of (-)-epigallocatechin-3-O-gallate (EGCG) and the O-methylated derivative, (-)-epigallocatechin-3-O-(3-O-methyl)gallate (EGCG3''Me), against ovalbumin-induced type I allergy in male mice were investigated. EGCG and EGCG3''Me exhibited strong antiallergic effects by oral administration at doses of 25 and 50 mg/kg body weight. The antiallergic effects of their C-2 epimers, (-)-gallocatechin-3-O-gallate and (-)-gallocatechin-3-O-(3-O-methyl)gallate (GCG3''Me), on mouse type I allergy were almost equivalent to and/or as strong as those of the corresponding original catechins, respectively. Oral administration of these compounds at a dose of 50 mg/kg body weight tended to suppress the increases in interleukin-4 levels in the abdominal walls of allergic mice and immunoglobulin E levels in the serum of allergic mice. In particular, the administration of GCG3''Me exhibited significant effects on the production and/or release of these parameters stimulating type 2 T helper cells and mast cells in the type I allergic process. These results indicated that C-2 epimerization of tea catechins, which are produced during heat processing at high temperatures, would not be disadvantageous for preventive effects on type I allergy.

Hyaluronidase inhibitors from "Cimicifugae Rhizoma" (a mixture of the rhizomes of Cimicifuga dahurica and C. heracleifolia).

From the 80% acetone extract of "Cimicifugae Rhizoma" (a mixture of Cimicifuga dahurica and C. heracleifolia used medicinally), seven new fukiic acid derivatives (1-7) and a new phenylethanoid derivative (8) were isolated along with eight known compounds (9-16). Fukinolic acid (9) and cimicifugic acids A-J (10-16, 5-7) showed stronger hyaluronidase inhibitory activities than the positive control, rosmarinic acid.

Hyaluronidase inhibitors from Takuran, Lycopus lucidus.

Takuran is a traditional herbal medicine that is produced from the herbal plant Lycopus lucidas TURCZ. (Lamiaceae). Takuran is used as a treatment for diseases in women. From Takuran, four new phenylpropanoids along with 18 known compounds were isolated, and their structures were elucidated by spectroscopic analyses. Five phenylpropanoids isolated from the plant showed hyaluronidase inhibitory activity comparable to that of rosmarinic acid.

Phenolic constituents of the aerial parts of Cimicifuga simplex and Cimicifuga japonica.

Chemical investigation of the aerial parts of Cimicifuga simplex afforded four new fukinolic acid analogues, cimicifugic acids K-N (1-4), and 10 known compounds, and C. japonica afforded three new fukinolic acid analogues, cimicifugic acids K-M (1-3), a new phenolic glycoside, shomaside F (5), and 10 known compounds. Cimicifugic acids K-N showed more potent hyaluronidase inhibitory activities than rosmarinic acid.

Antiestrogenic constituents of the Thai medicinal plants Capparis flavicans and Vitex glabrata.

Antiestrogenic compounds were investigated from Thai indigenous plants for galactogogues since estrogen is reported to suppress lactation in breastfeeding women. The aerial parts of the Thai medicinal plant Capparis flavicans, which has traditionally been used to promote lactation, gave the new compound capparoside A (1), along with 28 known compounds. The leaves of Vitex glabrata belong to the same genus as the chaste tree (Vitex agnus-castus), which is used traditionally to support lactation, and afforded the new compounds khainaoside A (14), khainaoside B (15), and khainaoside C (16), together with six known compounds. The isolates were tested for their biological activity using the estrogen-responsive human breast cancer cell lines MCF-7 and T47D. Syringaresinol (3) and principin (6), from C. flavicans, and khainaoside A (14) showed the most potent inhibitory effects on estrogen-enhanced cell proliferation among all compounds isolated. These results suggest that the lactation-promoting properties of C. flavicans might be related to the inhibitory effect on excess estrogen of women who experience insufficient breastfeeding and highlight the possibility of using V. glabrata leaves for their antiestrogenic properties.

Flavonoids from the heartwood of the Thai medicinal plant Dalbergia parviflora and their effects on estrogenic-responsive human breast cancer cells.

From the heartwood of Dalbergia parviflora, eight new compounds, khrinones A (1), B (2), C (3), D (4), and E (5), isodarparvinol B (6), dalparvin (7), and (3S)-sativanone (22), along with 32 known compounds, have been isolated and characterized as 17 isoflavones, nine isoflavanones, five flavanones, six isoflavans, and three miscellaneous substances. Isolates were evaluated for their cell proliferation stimulatory activity against the MCF-7 and T47D human breast cancer cell lines, and their luciferase inductive effects using luciferase transiently transfected MCF-7/luc and T47D/luc cells were also determined. Isoflavones such as genistein (10), biochanin A (11), tectorigenin (12), and 2'-methoxyformononetin (13) stimulated the proliferation of both cells, and concentrations of lower than 1 muM of these compounds showed equivalent activity to 10 pM of estradiol (E2). The new isoflavanone (22) also showed activity against both cell types, although it was weaker than that of the corresponding isoflavone (2'-methoxyformononetin, 13). Two optically active isoflavanones (22 and 24: (3S)-violanone) stimulated the proliferation of both cell lines at lower concentrations than three racemates (21: vestitone, 23: 7,3'-dihydroxy-4'-methoxyisoflavanone, and 25: 3-O-methylviolanone). Bowdichione (20), an isoflavone with a quinone structure in its B-ring, showed activity against only one cell line associated with MCF-7 in these assays.