Showing papers on "Triterpene published in 2015"

Dietary squalene supplementation improves DSS‐induced acute colitis by downregulating p38 MAPK and NFkB signaling pathways

Abstract: cope Squalene is a polyunsaturated triterpene, which has exhibited anticancer and antioxidant activities among others. We investigated dietary squalene supplementation effect on an acute colitis model induced by dextran sulfate sodium (DSS) in C57BL/6 mice. Methods and results Mice were fed from weaning with squalene at 0.02% and 0.1%. After 4 weeks, mice were exposed to 3% DSS for 5 days developing acute colitis. After DSS removal (5 days), colons were histological and biochemically processed. Our results showed that dietary squalene treatment exerts anti-inflammatory action in DSS-induced acute colitis. Western blot revealed that squalene downregulated COX-2 (where COX is cyclooxygenase) and inducible nitric oxide synthase system by inhibition of mitogen-activated protein kinase p38 and the nuclear factor-kappa B signaling pathways, preventing an increase in the cytokines levels. Under our experimental conditions, STAT3 and FOXP3 (where FOXP3 is forkhead box P3) were not modified and the transcriptional regulation of antioxidant and/or detoxifying enzymes, Nrf2 (where Nrf2 is nuclear factor (erythroid-derived 2)-like 2), was reduced in DSS-induced colitis. However, any change could be observed after squalene supplementation. Conclusion Squalene was able to improve the oxidative events and returned proinflammatory proteins expression to basal levels probably through p38 mitogen-activated protein kinase and nuclear factor-kappa B signaling pathways. However, supplementary studies are needed in order to provide a basis for developing a new dietary supplementation strategy.

Cucurbitacins from the Leaves of Citrullus colocynthis (L.) Schrad

Abstract: Two new tetracyclic cucurbitane-type triterpene glycosides were isolated from an ethyl acetate extract of Citrullus colocynthis leaves together with four known cucurbitacins. Their structures were established on the basis of their spectroscopic data (mainly NMR and mass spectrometry). Evaluation of the in vitro cytotoxic activity of the isolated compounds against two human colon cancer cell lines (HT29 and Caco-2) and one normal rat intestine epithelial cell line (IEC6), revealed that one of the isolated compounds presented interesting specific cytotoxic activity towards colorectal cell lines.

Hepatoprotective Triterpene Saponins from the Roots of Glycyrrhiza inflata

Abstract: Two novel oleanane-type triterpene saponins, licorice-saponin P2 (1) and licorice-saponin Q2 (3), together with nine known compounds 2, 4-11, have been isolated from the water extract of the roots of Glycyrrhiza inflata. The structures of these compounds were elucidated on the basis of spectroscopic analysis, including 2D-NMR experiments (1H-1H COSY, HSQC, HMBC and ROESY). In in vitro assays, compounds 2-4, 6 and 11 showed significant hepatoprotective activities by lowering the ALT and AST levels in primary rat hepatocytes injured by D-galactosamine (D-GalN). In addition, compounds 2-4, 6, 7 and 11 were found to inhibit the activity of PLA2 with IC50 values of 6.9 μM, 3.6 μM, 16.9 μM, 27.1 μM, 32.2 μM and 9.3 μM, respectively, which might be involved in the regulation of the hepatoprotective activities observed.

Triterpene glycosides of sea cucumbers (Holothuroidea, Echinodermata) as taxonomic markers.

Abstract: Triterpene glycosides are characteristic metabolites of sea cucumbers (Holothurioidea, Echinodermata). The majority of the glycosides belong to the holostane type {lanostane derivatives with an 18(20)-lactone}. Carbohydrate chains of these glycosides contain xylose, glucose, quinovose, 3-O-methylglucose, and, rarely, 3-O-methylxylose, 3-O-methylglucuronic acid, 3-O-methylquinovose, and 6-O-acetyl-glucose. The glycosides are specific for genera, groups of genera and even for species. The advantages and problems in the use of triterpene glycosides as taxonomic markers in the systematics of sea cucumbers are discussed.

Structure Identification of Triterpene from the Mushroom Pleurotus eryngii with Inhibitory Effects Against Breast Cancer

Abstract: Breast cancer is the leading cause of death among women, with approximately 1 million diagnoses annually. Triterpenoids, which have cancer preventive or anti-tumour efficacy towards various tumour cells, may play a role in breast cancer prevention. In our previous study, an acetic ether (EtOAc) fraction from the sporocarp of the edible mushroom Pleurotus eryngii (P. eryngii) exhibited significant tumour cell growth inhibition both in vitro and in vivo. In this study, three pentacyclic triterpenoid compounds (1-3) were isolated from EtOAc extracts using chromatographic separation and were identified using nuclear magnetic resonance (NMR) and mass spectrometry (MS). The compounds were 2, 3, 6, 23-tetrahydroxy-urs-12-en-28 oic acid (1), 2,3,23-trihydroxy-urs-12-en-28 oic acid (2) and lupeol (3). All three purified triterpenes showed significant inhibitory activity against breast cancer MCF-7 cell lines in vitro, with the greatest activity exhibited by compound 1, followed by compound 2 and 3. The IC(50) values were 15.71, 48 and 66.89 μM, respectively. Our study may help elucidate the health benefits of P. eryngii mushroom consumption.

Enrichment and separation of antitumor triterpene acids from the epidermis of Poria cocos by pH-zone-refining counter-current chromatography and conventional high-speed counter-current chromatography.

Abstract: Triterpene acids were extracted from the epidermis of Poria cocos (Schw.) Wolf. These acids were found to inhibit the growth of lung cancer cells in vitro and in vivo. An efficient method for the preparative separation of antitumor triterpene acids was established that involves the combination of pH-zone-refining counter-current chromatography and conventional high-speed counter-current chromatography. We used pH-zone-refining counter-current chromatography to concentrate the triterpene acids using a two-phase solvent system composed of petroleum ether/ethyl acetate/methanol/water (3:7:5:5, v/v/v/v), trifluoroacetic acid (10 mM) was added to the upper phase as a retainer, and ammonia (10 mM) was added to the lower phase as an eluter. As a result, 200 mg concentrate of triterpene acids was obtained from 1.0 g of crude extract. The concentrate was further separated by conventional high-speed counter-current chromatography using a solvent system composed of petroleum ether/ethyl acetate/methanol/water (0.8:1.2:1.2:0.9, v/v), yielding 50 mg of poricoic acid A and 5 mg of poricoic acid B from 120 mg concentrate, respectively. The inhibitory activity of the major compound on lung A549 cells was examined and poricoic acid A was found to significantly inhibit the growth of A 549 cells.

Antioxidant and anticholinesterase activities of lupane triterpenoids and other constituents of Salvia trichoclada

Abstract: The methanol extract of the aerial parts of Salvia trichoclada Bentham (Lamiaceae) was studied for bioactive non-volatile secondary metabolites, and nine compounds were isolated. Structures of the isolated compounds were elucidated as lupeol (1), lupenone (2), glochidone (3), monogynol A (4), oleanolic acid (5), ursolic acid (6), β-sitosterol (7), apigenin-7-O-rhamnoside (8), and rosmarinic acid (9) by using 1D and 2D-NMR spectroscopic techniques. A lupane triterpene glochidone was isolated from a Salvia species and Lamiaceae family for the first time in this study. The antioxidant potential of the extract and the isolated compounds were carried out by using lipid peroxidation inhibitory activity (β-carotene bleaching method) and DPPH free radical scavenging activity test assays. Their anticholinesterase activity was investigated by the Ellman method against both acetylcholinesterase (AChE) and butyrylcholinesterase enzymes. Compounds 1, 3, 5, 6, 8 and 9 showed fairly high anticholinesterase activity almost at all concentrations. Among them, a flavone glycoside apigenin-7-O-rhamnoside exhibited the highest and selective AChE inhibitory activity. Glochidone (3) was found to be the most active one among the isolated lupanes, which exhibited a close activity to that of standard compound galanthamine. Among all the tested compounds, rosmarinic acid (9) exhibited highest antioxidant and good anticholinesterase activity.

Cytotoxicity of Triterpenes from Green Walnut Husks of Juglans mandshurica Maxim in HepG-2 Cancer Cells.

Abstract: Among the classes of identified natural products, triterpenoids, one of the largest families, have been studied extensively for their diverse structures and variety of biological activities, including antitumor effects. In the present study, a phytochemical study of the green walnut husks of Juglans mandshurica Maxim led to the isolation of a new dammarane triterpene, 12β, 20(R), 24(R)-trihydroxydammar-25-en-3-one (6), together with sixteen known compounds, chiefly from chloroform and ethyl acetate extracts. According to their structural characteristics, these compounds were divided into dammarane-type, oleanane- and ursane-type. Dammarane-type triterpenoids were isolated for the first time from the Juglans genus. As part of our continuing search for biologically active compounds from this plant, all of these compounds were also evaluated for their cytotoxic activities against the growth of human cancer cells lines HepG-2 by the MTT assay. The results were shown that 20(S)-protopanaxadiol, 2α,3β,23-trihydroxyolean-12-en-28-oic acid and 2α,3β,23-trihydroxyurs-12-en-28-oic acid exhibited better cytotoxicity in vitro with IC50 values of 10.32±1.13, 16.13±3.83, 15.97±2.47 μM, respectively. Preliminary structure-activity relationships for these compounds were discussed.

Kadcoccinic Acids A–J, Triterpene Acids from Kadsura coccinea

Abstract: Eleven triterpene acids including 10 new compounds (kadcoccinic acids A–J, 1–10) were isolated from the stems of Kadsura coccinea. Except for 10, these compounds feature a rearranged lanostane skeleton with a 6/6/5/6 tetracyclic ring system, and compounds 1 and 2 are the first examples of 2,3-seco-6/6/5/6-fused tetracyclic triterpenoids. Their structures were established primarily by spectroscopic and spectrometric methods. Additionally, the absolute configuration of 3 was determined by single-crystal X-ray diffraction. Several of the compounds isolated were tested for their anti-HIV-1 and cytotoxic activities.

Novel Dammarane-Type Triterpene Saponins from Panax ginseng Root

Abstract: Four phytochemical constituents were isolated from Panax ginseng root by repeated column chromatography (CC), medium pressure liquid chromatography (MPLC), high-speed counter current chromatography (HSCCC), and semi-preparative HPLC. Their structures were elucidated as the dammarane-type triterpene saponins ginsenoside-Rg18 (1), 6-acetyl ginsenoside-Rg3 (2), ginsenoside-Rs11 (3), and ginsenoside-Re7 (4) based on spectral data. Compounds 1-4 from P. ginseng root were new compounds from nature. They showed good hydroxyl radical scavenging activity and anti-bacterial activity against Escherichia coli and Staphylococcus aureus. However, they did not show any anti-inflammatory activity. In addition, they inhibited the growth of adenocarcinoma gastric stomach cells. Among them, ginsenoside-Rs11 (3) showed the best anti-oxidative, anti-bacterial, and anti-cancer activities.

Cytotoxic triterpene glycosides from the roots of Sanguisorba officinalis

Abstract: Phytochemical investigation of the ethanol extract of the roots of Sanguisorba officinalis resulted in the isolation of three new triterpene glycosides, 3β-[(α-L-arabinopyranosyl)oxy]-19α,23-dihydroxyolean-12-en-28-oic acid 28-[6-O-acetyl-β-D-glucopyranosyl] ester (1), 2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid 28-[6-O-acetyl-β-D-glucopyranosyl] ester (2), and 3β-[(α-L-arabinopyranosyl)oxy]-19α-hydroxyurs-12,20(30)-dien-28-oic acid 28-[6-O-acetyl-β-D-glucopyranosyl] ester (3). All the triterpene glycosides exhibited the significant cytotoxic potential with low IC50 values (IC50 < 5.0 μM) against six tumor cell lines (MCF-7, HeLa, HepG2, SGC-7901, NCI-H460, and BGC-823).

Isolation and characterization of two squalene epoxidase genes from Botryococcus braunii, race B.

Abstract: The B race of the green microalga Botryococcus braunii produces triterpene hydrocarbons, botryococcenes and methylsqualenes that can be processed into jet fuels with high heating values. In this alga, squalene is also converted into membrane sterols after 2,3-epoxidation. In the present study, cDNA clones of two distinct squalene epoxidases (BbSQE-I and -II) were isolated. Predicted amino acid sequences encoded on these genes are 45% identical with each other. Introduction of BbSQE-I or -II into Saccharomyces cerevisie erg1 mutants resulted in the complementation of ergosterol auxotrophy. The relative expression level of SQE-II increased 3.5-fold from the early stage to the middle phase of a culture period of 42 days, while that of SQE-I was almost constant throughout the culture period. Southern blot analyses suggested that these genes are single-copied genes. This is the first report on the isolation of functional SQEs that are encoded in duplicated loci in the algal genome.

Simultaneous determination of five triterpene acids in rat plasma by liquid chromatography–mass spectrometry and its application in pharmacokinetic study after oral administration of Folium Eriobotryae effective fraction

Abstract: Folium Eriobotryae effective fraction (FEA), the extract of Folium Eriobotryae, had been used as anti-hyperglycemia and anti-hyperlipemia medicine in China. A previous study indicated that euscaphic acid, maslinic acid, corosolic acid, oleanolic acid and ursolic acid, the five structurally similar triterpene acids (containing two groups of structural isomers), are the major components of FEA. In the present study, we developed a specific and reliable LC-MS method for simultaneous determination of the five triterpene acids in rat plasma, and further investigated their pharmacokinetic properties after oral administration of FEA. Following a simple sample preparation, chromatographic separation was achieved on a C18 column with a mobile phase composed of methanol-0.1% ammonium acetate (80:20, v/v). Quantification was achieved by monitoring the selected ions at m/z 487.6 for euscaphic acid, m/z 471.5 for maslinic acid and corosolic acid, m/z 455.5 for oleanolic acid and ursolic acid and m/z 469.5 for internal standard. The method was validated to be specific, accurate and precise over the concentration ranges of 10-3000 ng/mL with limits of detections of 5 ng/mL for the five triterpene acids. Finally, the method was successfully applied to the pharmacokinetic study of the five structurally similar triterpene acids in rats after oral administration of FEA.

Triterpene glycosides with stimulatory activity on melanogenesis from the aerial parts of Weigela subsessilis

Abstract: Three new triterpene glycosides (Lonicerosides K, L and M) and 11 known compounds were isolated from the aerial parts of Weigela subsessilis. Among the known isolated compounds, loniceroside A, sweroside, kaempferol-3-O-glucopyranoside 6″-(3-hydroxy-3-methylglutarate), kaempferol-3-O-acetylglucoside and grandifloroside were reported for the first time in a Weigela genus plant. Their chemical structures were identified using extensive spectroscopic analysis including two-dimensional (2D)-NMR experiments, HR-ESI-QTOF-MS and comparison with reported data. Among these compounds, lonicerosides A and L had potent melanogenesis stimulatory activity in murine B16F0 melanoma cells. The structural relationship of active compounds was discussed.