Activity-guided isolation of saponins from Kalopanax pictus with anti-inflammatory activity

Hemolysis by Saponin Is Accelerated at Hypertonic Conditions

Saponins are a large group of organic amphiphilic substances (surfactants) mainly extracted from herbs with biological activity, considered as one of the main ingredients in numerous remedies used in traditional medicine since ancient times. Anti-inflammatory, antifungal, antibacterial, antiviral, antiparasitic, antitumor, antioxidant and many other properties have been confirmed for some. There is increasing interest in the elucidation of the mechanisms behind the effects of saponins on different cell types at the molecular level. In this regard, erythrocytes are a very welcome model, having very simple structures with no organelles. They react to changing external conditions and substances by changing shape or volume, with damage to their membrane ultimately leading to hemolysis. Hemolysis can be followed spectrophotometrically and provides valuable information about the type and extent of membrane damage. We investigated hemolysis of erythrocytes induced by various saponin concentrations in hypotonic, isotonic and hypertonic media using measurements of real time and end-point hemolysis. The osmotic pressure was adjusted by different concentrations of NaCl, manitol or a NaCl/manitol mixture. Unexpectedly, at a fixed saponin concentration, hemolysis was accelerated at hypertonic conditions, but was much faster in NaCl compared to mannitol solutions at the same osmotic pressure. These findings confirm the colloid-osmotic mechanism behind saponin hemolysis with pore formation with increasing size in the membrane.

Inhibition of Glucose Transport by Tomatoside A, a Tomato Seed Steroidal Saponin, through the Suppression of GLUT2 Expression in Caco-2 Cells

We investigated whether tomatoside A (5α-furostane-3β,22,26-triol-3-[O-β-d-glucopyranosyl (1→2)-β-d-glucopyranosyl (1→4)-β-d-galactopyranoside] 26-O-β-d-glucopyranoside), a tomato seed saponin, may play a role in the regulation of intestinal glucose transport in human intestinal Caco-2 cells. Tomatoside A could not penetrate through Caco-2 cell monolayers, as observed in the transport experiments using liquid chromatography-mass spectrometry. The treatment of cells with 10 μM tomatoside A for 3 h resulted in a 46.0% reduction in glucose transport as compared to untreated cells. Western blotting analyses revealed that tomatoside A significantly (p < 0.05) suppressed the expression of glucose transporter 2 (GLUT2) in Caco-2 cells, while no change in the expression of sodium-dependent glucose transporter 1 was observed. In glucose transport experiments, the reduced glucose transport by tomatoside A was ameliorated by a protein kinase C (PKC) inhibitor and a multidrug resistance-associated protein 2 (MRP2) inhibitor. The tomatoside A-induced reduction in glucose transport was restored in cells treated with apical sodium-dependent bile acid transporter (ASBT) siRNA or an ASBT antagonist. These findings demonstrated for the first time that the nontransportable tomato seed steroidal saponin, tomatoside A, suppressed GLUT2 expression via PKC signaling pathway during the ASBT-influx/MRP2-efflux process in Caco-2 cells.

Topical anti-inflammatory phytomedicine based on Sphagneticola trilobata dried extracts

CONTEXT

The aerial parts of Sphagneticola trilobata (L.) Pruski (Asteraceae) are popularly used to treat topical inflammation, but have not been fully investigated.

OBJECTIVE

To identify polar compounds in S. trilobata extracts and develop a new topical phytomedicine based on the kaurenoic acid (KA) content while monitoring and demonstrating its topical anti-inflammatory activity.

MATERIALS AND METHODS

Ethanol spray-dried extract of S. trilobata was analysed by LC-MS while the KA content from semisolid was analysed by LC-UV. The extent of ear edema induced by applying 20 μL of croton oil (2.5%), arachidonic acid (AA; 2 mg/ear) and decanoylphorbol-13-acetate (TPA; 2.5 mg/ear) in mice was used to evaluate the biological activity of the semisolids, which were applied 30 min before the phlogistic agents.

RESULTS

Eight phenylpropanoids and four oleanane-type triterpenoid saponins were identified, majority of them reported for the first time in this species, in addition to KA. The semisolid containing 1.0% of dried extract reduced the ear edema induced by croton oil [77.2 ± 4.5%; ID50 = 0.49 (0.28-0.87%)], TPA (81.5 ± 2.4%) and AA (39.1 ± 6.9%), with decreasing effect at higher KA concentrations. This was accompanied by neutrophil migration inhibition as investigated by biochemical and histological assays.

DISCUSSION AND CONCLUSION

The anti-inflammatory effects were (at least in part) due to the interference in protein kinase C (PKC) activation, AA-cascade products and neutrophil migration inhibition, demonstrating the efficacy of the folk topical usage of this plant. The results support the development of a novel topical anti-inflammatory phytomedicine properly standardized to treat inflammatory dermatological diseases.

Methyl syringate, a TRPA1 agonist represses hypoxia-induced cyclooxygenase-2 in lung cancer cells

BACKGROUND

We have previously found that methyl syringate is a specific and selective agonist of the human transient receptor potential channel ankyrin 1 (TRPA1) and suppresses food intake and gastric emptying in imprinting control region mice. Because TRPA1 has been implicated in inflammatory responses, and inflammation and tumorigenesis are stimulated by the cyclooxygenase-2 (COX-2)/prostaglandin E2 pathway in hypoxic cancer cells.

PURPOSE

This study examined the effects of methyl syringate on hypoxia-induced COX-2 in human distal lung epithelial A549 cells.

STUDY DESIGN

The effect of the methyl syringate on suppression of hypoxia-induced COX-2 in A549 cells were determined by Western blot and/or quantitative real-time polymerase chain reaction. The anti-invasive effect of methyl syringate was evaluated on A549 cells using matrigel invasion assay.

RESULTS

Methyl syringate suppressed hypoxia-induced COX-2 protein and mRNA expression and promoter activity and reduced hypoxia-induced cell migration and invasion and secretion of vascular endothelial growth factor. These effects were antagonized by a TRPA1 antagonist, implying their mediation by the TRPA1 pathway.

CONCLUSION

Together, these results indicate that methyl syringate inhibits the hypoxic induction of COX-2 expression and cell invasion through TRPA1 activation. These findings suggest that methyl syringate could be effective to suppress hypoxia-induced inflammation and indicate an additional functional effect of methyl syringate.

Biological synthesis of manganese dioxide nanoparticles by Kalopanax pictus plant extract

Manganese dioxide (MnO₂) nanoparticles were synthesised by the reduction of potassium permanganate (KMnO₄) using Kalopanax pictus leaf extract at room temperature. A transparent dark-brown colour appeared after the addition of K. pictus leaf extract to the solution of permanganate. The time course of the reduction of KMnO₄and synthesis of MnO₂ nanoparticles was monitored by means of UV-Vis spectra. The reduction of KMnO₄occurred after addition of plant extract with disappearance of KMnO₄specific peaks and emergence of peak specific for MnO₂nanoparticles. MnO₂nanoparticles showed absorption maxima at 404 nm. The electron dispersive X-ray spectroscopy analyses confirmed the presence of Mn and O in the sample. X-ray photoelectron spectroscopy revealed characteristic binding energies for MnO₂nanoparticles. Transmission electron microscopy micrographs revealed presence of uniformly dispersed spherical shaped particles with average size of 19.2 nm. The selected area electron diffraction patterns revealed the crystalline nature of MnO₂nanoparticles. Fourier transform-infrared spectroscopy spectra of pure MnO₂show the occurrence of O-Mn-O vibrational mode at around 518 cm⁻¹. The phyto-synthesised MnO₂nanoparticles showed degradation ability of dyes (congo red and safranin O) similar to chemically synthesised MnO₂nanoparticles. This study shows simple and eco-friendly synthesis of MnO₂nanoparticles by plant extract and their utilisation for dye degradation for the first time.

HPLC-ESI-MS/MS validation and pharmacokinetics of kalopanaxsaponin A in rats

A new LC-MS/MS method was developed and validated for the analysis of kalopanaxsaponin A in rat plasma.

Inhibitory effects of oleanane-type triterpenes and saponins from the stem bark of Kalopanax pictus on LPS-stimulated pro-inflammatory cytokine production in bone marrow-derived dendritic cells

Kalopanax pictus (Araliaceae) is a deciduous tree distributed in Korea, Japan, and China. The stem bark of K. pictus has been functionally used as a traditional crude drug for the treatment of various inflammatory diseases. In the present study, we describe the inhibitory effects of oleanane-type triterpenes and saponins isolated from the stem bark of K. pictus on production of pro-inflammatory cytokines in LPS-stimulated bone marrow-derived dendritic cells. Of the compounds tested, 16,23,29-trihydroxy-3-oxo-olean-12-en-28-oic acid (1), 4,23,29-trihydroxy-3,4-seco-olean-12-en-3-oate-28-oic acid (2), 3β,6β,23-trihydroxyolean-12-en-28-oic acid 28-O-β-D-glucopyranoside (3), nipponogenin E (6), 3β,6β,23-trihydroxyolean-12-en-28-oic acid (7), and caulophyllogenin (19) significantly inhibited the production of IL-12 p40 and IL-6 with IC50 values ranging from 3.3 to 9.1 μM. Compounds 2, 3, 7, and 19 significantly suppressed the secretion of TNF-α with IC50 ranging from 8.8 to 20.0 μM. These data provide scientific support for the use of K. pictus stem bark and its triterpene and saponin components in the inhibition of pro-inflammatory cytokine secretion, including IL-12 p40, IL-6, and TNF-α, and for prevention and treatment of inflammatory diseases.

The synthesis of cholestane and furostan saponin analogues and the determination of sapogenin's absolute configuration at C-22

A facile and efficient way for the synthesis of cholestane and furostan saponin analogues was established and adopted for the first time. Following this strategy, starting from diosgenin, three novel cholestane saponin analogues: (22S,25R)-3β,22,26-trihydroxy-cholest-5-ene-16-one 22-O-[O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside] 11, (25R)-3β,16β,26-trihydroxy-cholest-5-ene-22-one 16-O-[O-α-L-rhamnopyranosyl-(1→2)-α-D-glucopyranoside] 14 and (25R)-3β,16β,26-trihydroxy-cholest-5-ene-22-one 16-O-[O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside] 17, three novel furostan saponin analogues: (22S,25R)-furost-5-ene-3β,22,26-triol 22-O-(α-D-glucopyranoside) 23, (22R,25R)-furost-5-ene-3β,22,26-triol 22-O-(α-D-glucopyranoside) 24 and (22S,25R)-furost-5-ene-3β,22,26-triol 22-O-[O-α-L-rhamnopyranosyl-(1→2)-α-D-glucopyranoside] 26, were synthesized ultimately. The structures of all the synthesized analogues were confirmed by spectroscopic methods. The S-chirality at C-22 of cholestane was confirmed by Mosher's method. The absolute configuration at C-22 of furostan saponin analogues was distinguished by conformational analysis combined with the NMR spectroscopy. The cytotoxicities of the synthetic analogues toward four types of tumor cells were shown also.

The Stem Bark of Kalopanax pictus Exhibits Anti-inflammatory Effect through Heme Oxygenase-1 Induction and NF-κB Suppression

Background

The stem bark of Kalopanax pictus (KP) has been used in traditional medicine to treat rheumatoidal arthritis, neurotic pain and diabetes mellitus in China and Korea. In this study, the mechanism responsible for anti-inflammatory effects of KP was investigated.

Methods

We examined the effects of KP on NO production, nitric oxide synthase (iNOS) and HO-1 expression, NF-κB, Nrf2 and MAPK activation in mouse peritoneal macrophages.

Results

The aqueous extract of KP inhibited LPS-induced NO secretion as well as inducible iNOS expression, without affecting cell viability. KP suppressed LPS-induced NF-κB activation, phosphorylation and degradation of IκB-α, phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Furthermore, KP induced HO-1 expression and Nrf2 nuclear translocation.

Conclusion

These results suggest that KP has the inhibitory effects on LPS-induced NO production in macrophages through NF-κB suppression and HO-1 induction.

Induction of cell cycle arrest and apoptosis by the ethyl acetate fraction of Kalopanax pictus leaves in human colon cancer cells

Kalopanax pictus is a deciduous tree used in traditional medicine; its leaves are also consumed as a vegetable. In this study, the ethyl acetate fraction of K. pictus leaves (EFK) was tested in vitro for anticancer activity against four cell lines: human colon cancer (HT-29) cells, human stomach cancer (NCI-N87) cells, human breast cancer (MDA-MB231) cells, and mouse melanoma (B16F1) cells. Results indicated that EFK showed the most potent tumor selective growth inhibitory activity against HT-29 cells with less cytotoxic effect on normal cell lines. Cytotoxicity of EFK on HT-29 cells was associated mainly with cell chromatin condensation, DNA fragmentation, and loss of membrane phospholipid asymmetry with appearance of G2/M phase arrest. Cell death induced by EFK displayed features characteristic of apoptosis, and was associated with generation of reactive oxygen species (ROS) and increase of Bax/Bcl-2 ratio. These findings suggest that K. pictus leaves have anticancer properties and may be valuable for application in pharmaceutical industry.

Evaluation of the analgesic and anti-inflammatory effects of the essential oil of Lippia gracilis leaves

AIM OF THE STUDY

The aim of the present study is to investigate the antinociceptive, anti-inflammatory, and antioxidant activities of essential oil (EO) of Lippia gracilis Schauer (Verbenaceae) leaves to support the medicinal uses claimed by folklore practitioners in the caatinga region (semi-arid) of Northeastern Brazil.

MATERIALS AND METHODS

The chemical composition and antinociceptive and anti-inflammatory activities of the EO of Lippia gracilis leaves (50-200 mg/kg) were investigated. Antinociceptive activity of the EO was evaluated by writhing test. Anti-inflammatory activity of the EO was evaluated using paw oedema and peritonitis methods.

RESULTS

Oral treatment with the EO of Lippia gracilis leaves elicited inhibitory activity on acetic acid effect at 50, 100, and 200 mg/kg (30.33+/-2.36, 25.20+/-1.48, and 21.00+/-1.54 abdominal writhes, respectively, P<0.05), as compared with the control group (36.73+/-1.92 writhes). The compound acetylsalicylic acid (ASA, 300 mg/kg) inhibited the acetic acid-induced writhing (12.67+/-0.50 abdominal writhes, P<0.001). Carrageenan-induced oedema formation was reduced with the EO of Lippia gracilis leaves at 200 mg/kg (0.72+/-0.06 mL h, P<0.001) and by the reference compound ASA (300 mg/kg, 0.85+/-0.04 mL h, P<0.001), as compared with the control group (1.76+/-0.06 mL h). Leukocyte migration into the peritoneal cavity induced by carrageenan was reduced with the EO of Lippia gracilis leaves at 50, 100, and 200 mg/kg (13.81+/-0.61, 11.77+/-0.91, and 10.30+/-0.60 leukocytes x 10(6)/mL, respectively, P<0.01), and by the compound dexamethasone (2 mg/kg, 5.34+/-0.33 leukocytes x 10(6)/mL, P<0.001), as compared with the control group (16.71+/-0.54 leukocytes x 10(6)/mL). The analyses of the essential oil allowed the identification of Lippia gracilis as a thymol-p-cymene chemotype (32.68% and 17.82%, respectively).

CONCLUSIONS

The EO of Lippia gracilis leaves shows antinociceptive and anti-inflammatory activities.

Antinociceptive and anti-inflammatory activities of Bowdichia virgilioides (sucupira)

ETHNOPHARMACOLOGICAL RELEVANCE

Bowdichia virgilioides Kunth (Leguminosae Papilonoideae) is a plant with anti-inflammatory activity used in folk medicine. The importance of this plant promoted its inclusion in Brazilian Pharmacopoeia.

AIM OF THE STUDY

In order to evaluate the actions of this plant, studies were performed on antinociceptive and anti-inflammatory activities.

MATERIALS AND METHODS

The aqueous extracts (AE) of Bowdichia virgilioides inner bark and leaves were used at 100, 200, and 400mg/kg. Antinociceptive activity of plant extract was evaluated by writhing, hot-plate and formalin tests. Anti-inflammatory activity was evaluated using paw oedema and peritonitis methods.

RESULTS

Oral treatment with the AE of inner bark or leaves elicited inhibitory activity (P<0.01) on acetic acid effect at 200 and 400mg/kg, and reduced the formalin effect at the second-phase (200 and 400mg/kg, P<0.01), however it did not elicit any inhibitory effect on hot-plate test. The indomethacin inhibited the acetic acid-induced writhing and the formalin effect at the second-phase (P<0.001), and the morphine reduced the both phases of formalin test (P<0.001). Carrageenan-induced oedema formation and neutrophil migration into the peritoneal cavity were reduced with the AE of inner bark or leaves at 100, 200, and 400mg/kg (P<0.05), and by the reference compounds aspirin (P<0.001) and dexamethasone (P<0.001), respectively.

CONCLUSIONS

The AE of Bowdichia virgilioides shows antinociceptive and anti-inflammatory activities, supporting the folkloric usage of the plant to treat various inflammatory diseases.

Anti-ulcer, anti-inflammatory and antioxidant activities of the n-butanol fraction from Pteleopsis suberosa stem bark

Pteleopsis suberosa Engl. et Diels (Combretaceae) is a tree distributed in many African countries. The decoction from the stem bark is orally administered for the treatment of gastric ulcers in traditional medicine. Previous pharmacological studies reported the anti-ulcer activity of extracts from P. suberosa stem bark. In the present study, the anti-ulcer and anti-inflammatory effects of the n-butanol fraction (RBuOH) obtained from a methanol extract of P. suberosa bark were investigated on ethanol-induced gastric ulcers in rats and carrageenan-induced paw oedema in mice. Misoprostol (0.50 mg/kg, p.o.) and indomethacin (8.00 mg/kg, p.o.) were used as positive controls for anti-ulcer and anti-inflammatory activities, respectively. Results showed that RBuOH treatment significantly reduced the incidence of gastric lesions (50 mg/kg, P<0.05; 100 and 200 mg/kg, P<0.01) and restored the decreased levels of total sulfhydryl groups (T-SH) and non-protein sulfhydryl groups (NP-SH) (50, 100 mg/kg, P<0.05; 200 mg/kg, P<0.01) in the stomach homogenate. Moreover, RBuOH treatment attenuated MDA levels as index of lipid peroxidation in gastric mucosa. Administration of RBuOH at the same dosage (50, 100 and 200 mg/kg) reduced significantly (P<0.01) carrageenan-induced paw oedema in dose-dependent manner (from 42.81% to 87.81% inhibition, 5h after carrageenan injection). The anti-inflammatory effect of RBuOH at 200 mg/kg was comparable with that of indomethacin. Finally, RBuOH proved to possess elevated free radical scavenger capacity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (IC(50) 23.48 microg/ml) which may contribute to the observed anti-ulcer and anti-inflammatory activities.

Anti-inflammatory activities of ent-16αH,17-hydroxy-kauran-19-oic acid isolated from the roots of Siegesbeckia pubescens are due to the inhibition of iNOS and COX-2 expression in RAW 264.7 macrophages via NF-κB inactivation

To isolate the anti-inflammatory components in Siegesbeckia pubescens root, we performed activity-guided fractionation using a carrageenan-induced edema rat model. Antinociceptive effects were followed using acetic acid-induced abdominal constriction and hot plate tests in mice. Chloroform extract was subjected to silica gel and octadesyl silane (ODS) column chromatography, and a diterpene was isolated which was identified as ent-16alphaH,17-hydroxy-kauran-19-oic acid (siegeskaurolic acid). Pretreatment with siegeskaurolic acid (20 or 30 mg/kg/day, p.o.) exhibited anti-inflammatory and antinociceptive effects in these animal models. To investigate the mechanisms underlying this anti-inflammatory action, we investigated the effect of siegeskaurolic acid on lipopolysaccharide (LPS)-induced responses in a murine macrophage cell line, RAW 264.7. Siegeskaurolic acid was found to significantly inhibit the productions of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and tumor necrosis factor-alpha (TNF-alpha). Consistent with these findings, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins, and iNOS, COX-2, and TNF-alpha mRNAs were found to be inhibited by siegeskaurolic acid. Furthermore, siegeskaurolic acid inhibited the nuclear factor-kappaB (NF-kappaB) activation induced by LPS, and this was associated with the prevention of inhibitor kappaB degradation (I kappaB), and subsequently with decreased nuclear p65 and p50 protein levels. Taken together, our data indicate that the anti-inflammatory and antinociceptive properties of siegeskaurolic acid may be due to iNOS, COX-2 and TNF-alpha inhibition via the down-regulation of NF-kappaB binding activity.

Identification and evaluation of antioxidant, analgesic/anti-inflammatory activity of the most active ninhydrin–phenol adducts synthesized

Treatment of phenols with ninhydrin in acidic medium afforded 2-hydroxy-2-(ortho-hydroxy-phenyl/naphthyl)-1,3-dioxoindanes, which being unstable were isolated in their hemiketal forms. These synthesized compounds were subjected to TLC screening for radical scavenging and in vitro lipoxgenase and cycloxygenase enzyme inhibition assays. The best compound was identified and studied in detail for steady-state and time-resolved free radical kinetics, viz., DPPH, ABTS(-), *OH and rate constants for these reactions were evaluated. The best compound was also subjected to in vivo anti-inflammatory and analgesic activities in which the compound showed good promise for further structural optimization.

Synthesis, Anticonvulsant, and Anti-inflammatory Activities of Some New Benzofuran-Based Heterocycles

Treatment of 2-bromoacetylbenzofuran (2) with pyridine afforded its corresponding pyridinium bromide 3. The latter salt reacted with some activated alkenes and acetylenes to give the corresponding indolizine derivatives. Treatment of the salt 3 with benzylidenemalononitriles 9 afforded polysubstituted aniline derivatives, however with arylidenecyanothioacetamides 15 it gave the corresponding 4,5-dihydrothiophenes. Bromide 3 also coupled with p-chlorobenzenediazonium salt followed by ammonium acetate to give the corresponding 1,2,4,5-tetrazine derivative. The biological activity of the newly synthesized compounds was examined and some of them were found to possess anticonvulsant and anti-inflammatory activities.

Anti-inflammatory and free radical scavenging activity of Ricinus communis root extract

Anti-inflammatory and free radical scavenging activities of the methanolic extract of Ricinus communis (RCM) (Euphorbiaceae) Linn. root was studied in Wistar albino rats. The methanolic extract at doses 250 and 500 mg/kg p.o. exhibited significant (P<0.001) anti-inflammatory activity in carrageenan-induced hind paw edema model. The extract at the dose of 500 mg/kg p.o. also exhibited significant (P<0.001) anti-inflammatory activity in cotton pellet granuloma model. The methanolic extract showed significant free radical scavenging activity by inhibiting lipid peroxidation initiated by carbon tetrachloride and ferrous sulphate in rat liver and kidney homogenates. The extract enhanced free radical scavenging activity of stable radical 2,2-diphenyl-1-picryl-hydrazyl (DPPH*), nitric oxide and hydroxyl radical in in vitro assay methods. The results of the study indicate that the methanolic extract of Ricinus communis root possess significant anti-inflammatory activity in acute and chronic inflammatory models in rats. The observed pharmacological activity may be due to the presence of phytochemicals like flavonoids, alkaloids and tannins present in the plant extract with various biological activities.

Synthesis, anticonvulsant, and anti-inflammatory evaluation of some new benzotriazole and benzofuran-based heterocycles

Treatment of 2-bromoacetylbenzofuran with 1H-benzotriazole afforded 1-(benzofuran-2-yl)-2-(benzotriazol-1-yl)ethanone which reacted with phenylisothiocyanate to give the corresponding thioacetanilide derivatives. Treatment of the latter ethanone and thioacetanilide derivatives with hydrazonoyl chlorides afforded the corresponding pyrazole and 1,3,4-thiadiazole derivatives. The thioacetanilide derivative reacted with alpha-haloketones and alpha-halodiketones to afford thiophene and thiazole derivatives, respectively. The newly synthesized compounds were found to possess anticonvulsant and anti-inflammatory activities with the same mechanism of action of selective COX-2 inhibitors.

Induction of neurite outgrowth by (-)-(7R, 8S)-dihydrodehyd-rodiconiferyl alcohol from PC12 Cells

A lignan derivative, (-)-(7R, 8S)-dihydrodehydrodiconiferyl alcohol (DHDA), was isolated from Kalopanax septemlobus L. and was observed to have neuritogenic activity. DHDA at 50 microM caused a marked induction of neurite outgrowth and an enhancement of nerve growth factor (NGF)-mediated neurite outgrowth from PC12 cells. However, it did not exhibit any neurotrophic action. At 50 microM, DHDA enhanced NGF-induced neurite-bearing activity. This activity was partially blocked by the mitogen-activated protein kinase (MAPK) inhibitor PD98059 and by GF109203X, a protein kinase C (PKC) inhibitor. These results suggest that DHDA can induce neurite outgrowth and enhance NGF-induced neurite outgrowth from PC12 cells by amplifying up-stream steps such as MAPK and PKC.

Antinociceptive and Anti-Inflammatory Effects of the Saponin and Sapogenins Obtained from the Stem of Akebia quinata

The stem of Akebia quinata Decasisne (Lardizabalaceae) has been used to treat urinary tract inflammatory disease. It has been reported that saponins in medicinal plants may act as bioactive components after biodegradation to sapogenins in the gastrointestinal tract. To find the active components, we obtained the methanol (MeOH) extract from A. quinata stems and fractionated this extract into CHCl(3), butanol (BuOH), and H(2)O fractions. A saponin-containing BuOH fraction was refluxed in an acidic solution to yield the hydrolyzed fraction. Silica gel column chromatography separated kalopanaxsaponin A (1) from the BuOH fraction, and oleanolic acid (2) and hederagenin (3) were obtained from the hydrolyzed fraction. The antinociceptive effect was tested by hot plate-writhing and tail-flicks methods using mice, and the anti-inflammatory effect was assayed using carrageenan-induced rat edema against the following samples: the MeOH extract of A. quinata stems, its fractions, the isolated saponin, kalopanaxsaponin A, and the sapogenins hederagenin and oleanolic acid. The MeOH extract exhibited antinociceptive/anti-inflammatory effects by oral administration of 100 and 250 mg/kg doses, indicating that the MeOH extract has an antinociceptive/anti-inflammatory activity. The BuOH fraction (crude saponin) also significantly exhibited those bioactivities. Treatments with 10 and 30 mg/kg perorally of these two sapogenins produced significant antinociceptive/ anti-inflammatory effects in the rat, suggesting that the sapogenins may act as resultant active compounds. Compounds 2 and 3 inhibited dye leakage into the peritoneal cavity induced by acetic acid, and the latter was more active than the former. The anti-inflammtory effects were further supported by the reduction of carrageenan-induced lipid peroxidation and hydroxy radical content in serum. These results suggest that the antinociceptive/anti-inflammatory properties of the stem of A. quinata can be attributed to the sapogenins oleanolic acid and hederagenin.

Triterpenoids

This review covers the isolation and structure determination of triterpenoids including squalene derivatives, lanostanes, cycloartanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleannes, friedelanes, ursanes, hopanes, isomalabaricanes and saponins. The literature from January to December 2002 is reviewed and 221 references are used.

Anti-inflammatory effect of caffeic acid methyl ester and its mode of action through the inhibition of prostaglandin E2, nitric oxide and tumor necrosis factor-α production

The anti-inflammatory effects of caffeic acid (CA), caffeic acid methyl ester (CM) and di-O-acetylcaffeic acid (DAC) were investigated in rats using the carrageenin-induced edema model and the antinociceptive effects of these compounds were also assessed in mice by means of the acetic acid-induced abdominal constriction test and hot plate test. CM (10mg/kg, p.o.) showed the most potent anti-inflammatory and antinociceptive effects in these animal models. To investigate the mechanism of the anti-inflammatory action, we examined the effects of these compounds on the lipopolysaccharide (LPS)-induced NO and PGE2 responses in the murine macrophage cell line, RAW 264.7. Our data indicate that CM is the most potent inhibitor of NO and PGE2 production and it also significantly decreased tumor necrosis factor-alpha (TNF-alpha) release. Consistent with these observations, the protein and mRNA expression levels of iNOS and COX-2 were found to be inhibited by CM in a dose-dependent manner. Furthermore, CM inhibited the nuclear factor-kappaB (NF-kappaB) activation induced by LPS, which was associated with the prevention of the degradation of the inhibitor kappaB, and subsequently with decreased p65 protein levels in the nucleus. Taken together, our data indicate that the anti-inflammatory properties of CM might result from the inhibition of iNOS, COX-2 and TNF-alpha expression through the down-regulation of NF-kappaB binding activity.

Biological activities and distribution of plant saponins

Plant saponins are widely distributed amongst plants and have a wide range of biological properties. The more recent investigations and findings into their biological activities were summarized. Isolation studies of saponins were examined to determine which are the more commonly studied plant families and in which families saponins have been identified.

Antiinflammatory activity of alpha-hederin methyl ester from the alkaline hydrolysate of the butanol fraction of Kalopanax pictus bark extract

Three antiinflammatory saponin components were isolated from the alkaline hydrolysate of a butanol-soluble portion of Kalopanax pictus bark extract through an in vivo activity-guided fractionation procedure. The hydrolysate showed inhibition of adjuvant induced arthritis in rats. After further fractionation, the ethyl acetate fraction exhibited antiarthritic activity, which resulted in the isolation of alpha-hederin, alpha-hederin methyl ester, and kalopanaxsaponin I. All compounds showed inhibition of vascular permeability in mice, but only alpha-hederin methyl ester showed anticarrageenan activity in rats and antiarthritic activity in rats and mice.

Antinociceptive and Antiinflammatory Effects of Niga-ichigoside F1 and 23-Hydroxytormentic Acid Obtained from Rubus coreanus

As an attempt to search for bioactive natural constituents exerting antinociceptive and antiinflammatory activities, we examined the potency of the extract of Rubus coreanus fruits by the activity-guided fractionation. The EtOAc- and BuOH fraction and those alkaline hydrolysates showed significant antinociceptive effects as assessed by writhing-, hot plate- and tail flicks tests in mice and rats as well as antiinflammatory effect in rats with carrageenan-induced edema. BuOH extract was subjected to column chromatography to obtain a large amount of niga-ichigoside F(1) (1,23-hydroxytormentic acid 28-O-glc), which was again hydrolyzed in NaOH solution to yield an aglycone 23-hydroxytormentic acid (1a). The aglycone, 23-hydroxytormentic acid, was much more potent in both antinociceptive and antiinflammatory tests than the glycoside, niga-ichigoside F(1). The antiinflammatory effects of these compounds were further supported by the reduction of carrageenan-induced lipid peroxidation and hydroxyl radical in serum. These results suggested that 23-hydroxytormentic acid might be an active moiety of niga-ichigoside F(1) present in R. coreanus.