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Four new biphenyl and biphenyl ether quinolizidine N-oxide alkaloids, 5- EPI-dihydrolyfoline N-oxide (1), decamine N-oxide (2), lagerstroemine N-oxide (3), and lagerine N-oxide (4), were isolated from the aerial parts of Lagerstroemia indica, and their structures were established by extensive spectroscopic studies. In addition, the inhibitory effects of isolated compounds on rat lens aldose reductase (RLAR) were examined., (© Georg Thieme Verlag KG Stuttgart · New York.)

Two new lignans, (2 R,3 R)-2 β-(4''-hydroxy-3''-methoxybenzyl)-3 α-(4'-hydroxy-3'-methoxybenzyl)-γ-butyrolactone 2-O-( β-D-glucopyranoside) (1) and (1 S,2 R,3 S)-dimethyl-1,2,3,4-tetrahydro-3,6,7-trihydroxy-1-(3',4'-dihydroxyphenyl)naphthalene-2,3-dicarboxylate (2) together with nine known compounds (3-11) were isolated from the ethyl acetate fraction of the roots of Pulsatilla koreana. Their chemical structures were established based on physicochemical and spectroscopic data analyses. All isolates were investigated for their inhibition effects against the classical pathway of the complement system. Among them, compound 6 showed significant inhibitory activity with an IC (50) value of 75.9 µM, compounds 8 and 9 had moderate effects with IC (50) values of 182.2 and 166.5 µM, respectively., (© Georg Thieme Verlag KG Stuttgart · New York.)

In the course of screening plants used in folk medicine as memory enhancers, a 70% ethanolic extract of Stephania rotunda roots showed significant AChE inhibitory activity. Repeated column chromatography led to the isolation of a new protoberberine alkaloid, which we named stepharotudine (1), and seven known compounds (2-8). The chemical structures of the isolated compounds were elucidated based on extensive 1D and 2D NMR spectroscopic data. Compounds 1-8 were investigated in vitro for their anticholinesterase activity using a rat cortex AChE enzyme., (© Georg Thieme Verlag KG Stuttgart · New York.)

Two new lanostane triterpenes, methyl lucidenate N ( 1) and T-butyl lucidenate B ( 2), were isolated from the fruiting bodies of GANODERMA LUCIDUM together with five known compounds ( 3- 7). The structures of the two new triterpenes were established as methyl 3 β,7 β-dihydroxy-4,4,14 α-trimethyl-11,15-dioxo-5 α-chol-8-en-24-oate ( 1) and T-butyl 7 β,12 β-dihydroxy-4,4,14 α-trimethyl-3,11,15-trioxo-5 α-chol-8-en-24-oate ( 2) by extensive spectroscopic studies and chemical evidence. The effect of the isolated compounds ( 1- 7) on triglyceride (TG) accumulation, an indicator of adipocyte differentiation, during the differentiation of 3T3-L1 preadipocytes was examined. T-Butyl lucidenate B ( 2) reduced the TG accumulation significantly by 72 % at 80 µM compared to the untreated group. Furthermore, compound 2 effectively suppressed the GPDH activity in the cells. Consistent with the decrease in TG accumulation and GPDH activity, compound 2 suppressed the gene expressions of PPAR γ, C/EBP α, and SREBP-1c in a dose-dependent manner during differentiation. Our findings demonstrate that the lanostane triterpenes isolated in this study contribute to the inhibitory effect of the fruiting bodies of G. LUCIDUM on adipocyte differentiation in 3T3-L1 cells., (© Georg Thieme Verlag KG Stuttgart · New York.)

Chemical investigation of the stems and leaves of Rhus Sylvestris afforded a new megastigmane glycoside named rhusonoside A ( 1), along with four other known compounds: dihydroquercetin ( 2), astragalin ( 3), hyperin ( 4), and kaempferol-3- O-rutinoside ( 5). Their structures were determined by a combination of spectroscopic analysis and application of the modified Mosher's method. The effect of compounds 1 - 5 on the function of osteoblastic MC3T3-E1 cells was examined by determining cell viability, alkaline phosphatase (ALP) activity, collagen synthesis, and mineralization. Rhusonoside A ( 1) significantly increased the function of osteoblastic MC3T3-E1 cells. Cell viability, ALP activity, and collagen synthesis were increased dose dependently, up to 155.39 %, 171.27 %, and 134.25 %, respectively, of the basal value at 10 muM ( P < 0.05). In addition, 0.1 muM of compound 1 significantly increased mineralization of MC3T3-E1 cells to 142.78 % ( P < 0.05) of the basal value.

To provide a better understanding of the anti-complement activity of triterpenoids, seven unusual pentacyclic triterpenoids bearing a carboxyl group at C-27 were evaluated for their anticomplement activities against the classical pathway of the complement system. The triterpenoids were isolated from the whole plant of Aceriphyllum rossii of the family Saxifragaceae and were determined to be 3alpha,23-isopropylidenedioxyolean-12-en-27-oic acid (1), 3-oxoolean-12-en-27-oic acid (2), 3alpha-hydroxyolean-12-en-27-oic acid (3), beta-peltoboykinolic acid (4), 3alpha,23-diacetoxyolean-12-en-27-oic acid (5), 23-hydroxy-3-oxoolean-12-en-27-oic acid (6) and aceriphyllic acid A ( 7). Among them, compounds 2, 3, and 5 showed significant anticomplement activity on the classical pathway with IC (50) values of 71.4, 98.5, and 180.7 microM, respectively, whereas compounds 1, 4, 6, and 7 were inactive. Our findings suggest that both the ketone at C-3 and the methyl at C-23 in the oleanane triterpenoids with a carboxyl group at C-27 are important for the anticomplement activity against the classical pathway.

The aim of this study was to investigate the antioxidant activity of magnoflorine, an alkaloid isolated from Coptidis Rhizoma, against the oxidation of native low density lipoprotein (LDL) and modified LDL. Magnoflorine was found to inhibit the copper-mediated (Cu2+) oxidation of LDL, as well as of glycated and glycoxidated LDL by increasing the lag time of conjugated diene formation and preventing the generation of thiobarbituric acid reactive substances (TBARS). In addition, the results from the fluorescence emission spectra of tryptophan (Trp) supported that the antioxidant activity of magnoflorine could be associated with the protective effect on the structural modification of apolipoprotein B (apoB) required for LDL oxidation. These results suggest that magnoflorine may be useful for preventing the oxidation of various LDL forms.

Patridoids I, II and IIA, are new iridoids isolated from the whole plants of Patrinia saniculaefolia. These compounds were examined by assessing their effects on the production of tumor necrosis factor-alpha (TNF-alpha) as well as by investigating the expression of two enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), in the lipopolysaccharide (LPS)-stimulated murine macrophage-like cell line, Raw 264.7. Among them, patridoid II consistently inhibited nitric oxide (NO) and TNF-alpha production in a dose-dependent manner, with IC (50) values of 14.1 and 17.6 microM, respectively. Western Blotting probed with specific anti-iNOS antibodies showed that the decrease in the quantity of the NO product was accompanied by a decrease in the iNOS protein level. However, all three patridoids did not affect the COX-2 protein expression level in the LPS-stimulated macrophages. In addition, the C-5 isomer of patridoid II, patridoid I, only slightly affected the production of NO. Moreover, the C-3 isomer of patridoid II, patridoid IIA, did not inhibit proinflammatory cytokines and NO production. These results suggest that the orientations of the C-3 and C-5 methoxy groups in the patridoids have a significant role in the expression of their biological activity.

The aim of this study was to investigate the protective effect of honokiol and magnolol on hepatocyte injury induced by either tertiary butyl hydroperoxide (tBH)- or D-galactosamine (GalN). The cellular leakage of LDH and AST, and cell death by treatment with 1.5 mM tBH for 1 h, were significantly inhibited by treatment with honokiol (40 and 20 microM) or magnolol (40 microM). Treatment with honokiol or magnolol significantly inhibited lipid peroxidation in both cells and media, the generation of intracellular reactive oxygen species (ROIs), and intracellular glutathione (GSH) depletion induced by tBH. The cellular leakage of LDH and AST, and cell death, by 24-hour treatment with 30 mM GalN were significantly inhibited by treatment with honokiol (20, 5 and 1 microM) or magnolol (20, 5 and 1 microM). Treatment with honokiol (20, 5 and 1 microM) or magnolol (20 and 5 microM) significantly inhibited the intracellular GSH depletion induced by GalN. The hepatoprotective effects of honokiol and magnolol on oxidative stress induced by tBH were probably the result of their antioxidant activity. Honokiol and magnolol also had a protective effect against GalN-induced hepatotoxicity, which was used as an alternate model to oxidative stress, acting by inhibiting intracellular GSH depletion.

Eight sesquiterpene lactones, 4 alpha,5 alpha-epoxy-10 alpha,14-dihydro-inuviscolide (1), 2,3-dihydroaromomaticin (2), carpesiolin (3), carabrone (4), carabrol (5), telekin (6), ivalin (7) and 11,13-didehydroivaxillin (8), were isolated from the aerial parts of Carpesium abrotanoides Linne (Compositae). In vitro cytotoxicity testing was carried out against L1210, A549, SK-OV-3, SK-MEL-2, XF-498 and HCT-15 tumor cell lines. Sesquiterpene lactone compounds 1 - 8 showed significant cytotoxic activity (ED50 values, < 20 microM) against all tumor call lines tested. Among these compounds, 4 alpha,5 alpha-epoxy-10 alpha,14-dihydro-inuviscolide (1), 2,3-dihydroaromomaticin (2), telekin (6) and ivalin (7) showed cytotoxic activity (ED50, < 10 microM) comparable to that of cisplatin.

Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans.

The methanolic extract from the root of Scutellaria baicalensis Georgi and its flavonoids, wogonin, baicalein, and baicalin were evaluated for anti-inflammatory action and the activatory effect on gingival fibroblasts. In LPS-induced production of IL-1 beta, three flavonoids at 1 microgram/ml expressed a significant (> 50%) inhibitory effect, similar to that of prednisolone. Moreover, the flavonoids inhibited IL-1 beta-induced synthesis of PGE2 and LTB4 considerably, although the effect of wogonin on LTB4 synthesis was marginal. In addition, three flavonoids exerted a moderate inhibition (33-36%) of collagenolytic activity, comparable to 40% inhibition by tetracycline. Meanwhile, the cellular activity of fibroblasts was augmented remarkably (40%) by baicalein (2) and slightly by baicalin (3) or wogonin (1). Consistent with the cellular activation, flavonoids enhanced the synthesis of both collagen and total protein in fibroblasts, in contrast to growth factors which increased only the synthesis of total protein. Although the effects of the methanolic extract resembled those of the flavonoids, the extract expressed a preferential effect on the synthesis of collagen and total protein.