Effects of phenylpropanoid and iridoid glycosides on free radical-induced impairment of endothelium-dependent relaxation in rat aortic rings.

The protective effect of phenylpropanoid glycosides, forsythoside B and alyssonoside, and the iridoid glycoside lamiide, isolated from the aerial parts of Phlomis pungens var. pungens, against free radical-induced impairment of endothelium-dependent relaxation in isolated rat aorta was investigated. Aortic rings were exposed to free radicals by the electrolysis of the physiological bathing solution. Free radical-induced inhibition of the endothelium-dependent relaxation in response to acetylcholine was countered by incubation of the aortic rings before electrolysis with the aqueous extract (200 microg/ml), phenylpropanoid fraction (100 microg/ml) and iridoid fraction (150 microg/ml) of P. pungens var. pungens. Major components of the phenylpropanoid fraction forsythoside B and alyssonoside also prevented the inhibition of the acetylcholine response, at 10(-4) M concentration. However, the major component of iridoid fraction lamiide was found ineffective at the same concentration. The protective activity of phenylpropanoid glycosides against the free radical-induced impairment of endothelium-dependent relaxation may be related to their free radical scavenging property.

Polyphenolic compounds from Geranium pratense and their free radical scavenging activities.

Two new polyphenolic compounds, myricetin 3-O-(2"-O-galloyl)-beta-D-glucopyranoside and (-)-6-chloroepicatechin, were isolated from the aerial parts of Geranium pratense subsp. finitimum (Woronow) Knuth, along with three known polyphenolic compounds [quercetin 3-O-(2"-O-galloyl)-beta-D-glucopyranoside, quercetin 3-O-(2"-O-galloyl)-beta-D-galactopyranoside, methyl gallate] and tryptophan. Quercetin 3-O-beta-D-glucopyranoside, quercetin 3-O-beta-D-galactopyranoside, quercetin 3-O-(2"-O-galloyl)-beta-D-glucopyranoside and quercetin 3-O-(2"-O-galloyl)-beta-D-galactopyranoside were found to be effective against free radical induced impairment of endothelium-dependent relaxation in isolated rat aorta.

Induction of apoptotic cell death in HL-60 cells by acteoside, a phenylpropanoid glycoside.

Acteoside, a phenylpropanoid glycoside with anti-oxidative activity, induced cell death in promyelocytic leukemia HL-60 cells with an IC50 value of 26.7/microM. Analysis of extracted DNA on agarose gel electrophoresis revealed that acteoside induced the internucleosomal breakdown of chromatin DNA characteristic of apoptosis. Apoptosis-specific DNA fragmentation was clearly detectable 4 h after treatment with acteoside and was independent of the cell cycle phase. These data indicate that acteoside induces apoptosis in HL-60 cells.

Induction of cytokines by a phenylpropanoid glycoside acteoside.

A phenylpropanoid glycoside acteoside was found to induce interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-alpha) in macrophage-like cell line J774.A1 at 1-100 ng/ml. In addition, when the stimulatory action of acteoside was studied using the bovine glomerular endothelial cell line GEN-T, it stimulated IL-6 production. These stimulatory activities were not abolished by treatment with polymixin B, which inactivates lipopolysaccharide (LPS), indicating that the action was not a contamination of LPS.

Minor saponins from Tetrapanax papyriferum.

Four new minor saponins, papyrioside LE-LH, were isolated from the leaves of Tetrapanax papyriferum, and their structures were determined on the basis of spectroscopic evidence.

Four novel cycloartane glycosides from Astragalus oleifolius.

Four novel cycloartane-type triterpene glycosides, macrophyllosaponins A-D (1-4) were isolated from the roots of Astragalus oleifolius. By means of chemical (acetylation, alkaline hydrolysis) and spectroscopic methods (IR, 1D- and 2D-NMR, FABMS), their structures were established as 3-O-alpha-L-rhamnopyranosyl-24-O-(4"-O-acetyl)-beta-D-xylopyranosyl-1 alpha,3 beta,7 beta,24(S), 25-pentahydroxycycloartane (1), 3-O-alpha-L-rhamnopyranosyl-24-O-beta-D-xylopyranosyl-1 alpha,3 beta, 7 beta,24(S), 25-pentahydroxycycloartane (2), 3-O-alpha-L-rhamnopyranosyl-25-O-beta-D-glucoyranosyl-1 alpha, 3 beta,7 beta,24(S),25-pentahydroxycycloartane (3), and 3-O-alpha-L-rhamnopyranosyl-24-O-(2-O-beta-D-xylopyranosyl) -beta-D-xylopyranosyl-1 alpha,3 beta,7 beta,24(S), 25-pentahydroxycycloartane (4).

Triterpene saponins from Tetrapanax papyriferum K. Koch.

Four new oleanane-type saponins, papyrioside LA--LD, were isolated from the leaves of Tetrapanax papyriferum. The structures of these new compounds were elucidated as 11 alpha-hydroxy-3,21-dioxo-olean-12-en-28-oyl-alpha-L-rhamnopyranosy l- (1-->4)-(6-O-acetyl-beta-D-glucopyranosyl)-(1-->6)- beta-D-glucopyranoside, 11 alpha-methoxy-3,21-dioxo-olean-12-en-28-oyl-alpha-L-rhamnopyranosy l- (1-->4)-(6-O-acetyl-beta-D-glucopyranosyl)-(1-->6)- beta-D-glucopyranoside, 3 alpha-hydroxy-11 alpha-methoxy-21-oxo-olean-12-en-28-oyl-alpha-L-rhamnopyranosyl-(1 -->4)- (6-O-acetyl-beta-D-glucopyranosyl)-(1-->6)-beta-D-glucopyranoside and 21 alpha-hydroxy-11 alpha-methoxy-3-oxo-olean-12-en-28-oyl-alpha-L- rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)- beta-D-glucopyranoside, respectively, on the basis of spectroscopic and chemical evidence.

Studies on constituents with cytotoxic and cytostatic activity of two Turkish medicinal plants Phlomis armeniaca and Scutellaria salviifolia.

Ten known glycosidic compounds, betulalbuside A (1), 8-hydroxylinaloyl,3-O-beta-D-glucopyranoside (2) (monoterpen glycosides), ipolamide (3) (iridoid glycoside), acteoside (verbascoside) (4), leucosceptoside A (5), martynoside (6), forsythoside B (7), phlinoside B (8), phlinoside C (9), and teuerioside (10) (phenylpropanoid glycosides) were isolated from methanolic extracts of Phlomis armeniaca and Scutellaria salviifolia (Labiatae). Structure elucidations were carried out using 1H-, 13C-NMR and FAB-MS spectra, as well as chemical evidence. The cytotoxic and cytostatic activities of isolated compounds were investigated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) method. Among the glycosides obtained here, caffeic acid-containing phenylpropanoid (or phenethyl alcohol, or phenylethanoid) glycosides were found to show activity against several kinds of cancer cells. However, they didn't affect the growth and viability of primary-cultured rat hepatocytes. Study of the structure-activity relationship indicated that ortho-dihydroxy aromatic systems of phenylpropanoid glycosides are necessary for their cytotoxic and cytostatic activities.

Two phenethyl alcohol glycosides from Scutellaria orientalis subsp. pinnatifida.

Two new phenethyl alcohol glycosides, darendoside A and B (= deacyl martynoside) were isolated from the methanolic extract of the aerial parts of Scutellaria orientalis subsp. pinnatifida, along with four known glycosides, syringin, martynoside, leucosceptoside A and verbascoside. On the basis of chemical and spectral evidence the structures of darendoside A and B were determined as beta-(4-hydroxyphenyl)ethyl O-beta-D-apiofuranosyl-(1-->2)-O-beta-D-glucopyranoside and beta-(3-hydroxy-4-methoxyphenyl)ethyl O-alpha-L-rhamnopyranosyl-(1-->3)-O-beta-D-glucopyranoside (= deacyl martynoside), respectively.

Phlinosides D and E, phenylpropanoid glycosides, and iridoids from Phlomis linearis.

Two new phenylpropanoid glycosides, phlinosides D and E were isolated from the methanolic extract of the aerial parts of Phlomis linearis, along with the known iridoid glucosides, lamiide, ipolamiide and auroside (= 5-hydroxy-8-epiloganin). On the basis of chemical and spectral evidence the structures of phlinosides D and E were determined as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-xylopyranosyl-(1----2)-al pha-L-rhamnopyranosyl-(1----3)-4-O-feruloyl-beta-D-glucopyranoside and 3,4-dihydroxy-beta-phenylethoxy-O-alpha-L-rhamnopyranosyl-(1----2) -alpha-L- rhamnopyranosyl-(1----3)-4-O-feruloyl-beta-D-glucopyranoside, respectively.

Phlinosides A, B and C, three phenylpropanoid glycosides from Phlomis linearis.

Three new phenylpropanoid glycosides, phlinosides A, B and C were isolated from a methanolic extract of the aerial parts of Phlomis linearis. On the basis of chemical and spectral evidence their structures were determined as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-glucopyranosyl-(1----2)-a lpha-L- rhamnopyranosyl-(1----3)-4-O-caffeoyl-beta-D-glucopyranoside, 3,4 dihydroxy-beta-phenylethoxy-O-beta-D-xylopyranosyl-(1----2)-alpha- L- rhamnopyranosyl-(1----3)-4-O-caffeoyl-beta-D-glucopyranoside and 3,4-dihydroxy-beta-phenylethoxy-O-alpha-L-rhamnopyranosyl-(1----2) -alpha- L-rhamnopyranosyl-(1----3)-4-O-caffeoyl-beta-D-glucopyranoside, respectively.