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PubMed2003

Inhibition of DNA polymerases and DNA topoisomerase II by triterpenes produced by plant callus.

We found that some triterpene compounds could not only selectively inhibit the activities of mammalian DNA polymerase alpha (pol alpha) and beta (pol beta), but could also potently inhibit DNA topoisomerase II (topo II) [Biochem. J. 350 (2000) 757]. Here, we report that natural triterpenes produced by callus from an ancient Chinese medicinal plant were also inhibitors of the enzymes, and some were more selective than others. The natural triterpenes with a carboxyl group equally inhibited the activities of pol alpha, pol beta, and topo II, while the olide-type triterpenes with a ketone group suppressed the activities of pol beta and topo II, but not pol alpha. The other triterpenes from the callus hardly influenced these enzyme activities. As also described previously [J. Biochem. 130 (2001) 657], pol beta and topo II have a three-dimensionally similar triterpene-binding region, which is a pocket in which specific compounds can insert. The newly found triterpene inhibitors might structure-dependently insert into the pocket, and the pocket structure of each enzyme might, three-dimensionally but slightly, differ among them. The triterpene frames could be used for screening new inhibitors of the enzymes, and computer-simulated drug design using the frame and pocket structure may in theory be a possible approach to develop new inhibitors.

DNA Polymerase I↗
PubMed1982

Herbal remedies of the Maritime indians: sterols and triterpenes of Tanacetum vulgare L. (Tansy).

Plant sterols and triterpenes exhibit a wide range of pharmacological activities. As part of our ongoing studies of the medicinal aspects of Maritime flora, particularly the herbal remedies of the Micmac and Malecite Indians, we determined the nature of the sterols and triterpenes of Tanacetum vulgare L. (Compositae)-a widely used herbal remedy usually referred to as tansy. By using thin layer and gas chromatographics, nuclear magnetic resonance (NMR) spectroscopy and combined gas chromatography-mass spectrometry, we were able to identify beta-sitosterol as the major sterol and alpha-amyrin as the major triterpene of tansy. We also identified the sterols stigmasterol, campesterol and cholesterol, and the triterpenes beta-amyrin and taraxasterol. A fourth triterpene was tentatively identified as pseudo-taraxasterol. The successful therapeutic application of this herb may be due partly to the presence of one or more of these compounds. The sterols and triterpenes of tansy have not been previously reported; neither, to our knowledge, have the NMR spectra of the amyrins and the NMR and mass spectra of taraxasterol.

Chromatography, Thin Layer↗
PubMed1999

Effects of sesquiterpenes and triterpenes from the rhizome of Alisma orientale on nitric oxide production in lipopolysaccharide-activated macrophages: absolute stereostructures of alismaketones-B 23-acetate and -C 23-acetate.

The methanolic extract from a Chinese herbal medicine, the rhizome of Alisma orientale, was found to exhibit inhibitory activity of nitric oxide (NO) production in lipopolysaccharide (LPS)activated macrophages. Novel triterpenes, alismaketones-B 23-acetate and -C 23-acetate, were isolated from the active extract together with eight sesquiterpenes and eighteen protostane-type triterpenes. The absolute stereostructures of new triterpenes were characterized on the basis of chemical and physicochemical evidence, which included the chemical correlations with known triterpenes. The guaiane-type sesquiterpenes (alismol, orientalols A and C) and protostane- and seco-protostane-types triterpenes (alisols C monoacetate, E-23-acetate, F, H, I, L-23-acetate, and M-23-acetate, alismaketones-B 23-acetate and -C 23-acetate, alismalactone 23-acetate, and 3-methylalismalactone 23-acetate) inhibited LPS-induced NO production (IC50 = 8.4-68 microM). Other triterpenes (alisols A, A monoacetate, B, B monoacetate, E, G, K-23-acetate, and N-23-acetate and 11-deoxyalisol B) also showed the potent inhibitory activity, but they showed cytotoxic effects more than 30 microM (MTT assay). In addition, alismol and alisol F were found to suppress iNOS induction.

Animals↗
PubMed2001

Constituents of compositae plants. 2. Triterpene diols, triols, and their 3-o-fatty acid esters from edible chrysanthemum flower extract and their anti-inflammatory effects.

The n-hexane soluble and the nonsaponifiable lipid fractions of the edible flower extract of chrysanthemum (Chrysanthemum morifolium) were investigated for triterpene diol and triol constituents. These triterpenes occur as the 3-O-fatty acid esters in the n-hexane soluble fraction from which 26 new and 6 known fatty acid esters were isolated and characterized. From the nonsaponifiable lipid fraction, 24 triterpene diols and triols were isolated, of which 3 were new compounds: (24S)-25-methoxycycloartane-3beta,24-diol (11), (24S)-25-methoxycycloartane-3beta,24,28-triol (22), and 22alpha-methoxyfaradiol (23). Faradiol (9) and heliantriol C (19), present in the nonsaponifiable lipid fraction and as the 3-O-palmitoyl esters in the n-hexane soluble fraction, were the most predominant triterpene diol and triol constituents. Fourteen triterpene diols and triols and 9 fatty acid esters were evaluated with respect to their anti-inflammatory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in mice. All of the triterpenes examined showed marked inhibitory activity, with a 50% inhibitory dose (ID50) of 0.03-1.0 mg/ear, which was more inhibitive than quercetin (ID50 = 1.6 mg/ear), a known inhibitor of TPA-induced inflammation in mice.

Animals↗
PubMed2006

Physical, chemical and pharmacological characterization of a new oleogel-forming triterpene extract from the outer bark of birch (betulae cortex).

Triterpenes are biologically active secondary plant substances that display antimicrobial, hepatoprotective and anti-inflammatory effects. However, the poor solubility of triterpenes in both polar and non-polar solvents as well as expensive purification procedures have prevented the large-scale isolation of these compounds for medicinal purposes. Here, we describe a novel quantitative extraction method of triterpenes from the outer bark of birch (Betula species) in which betulin, a lupan triterpene, predominates. The resulting highly purified triterpene extract (TE) in the form of a dry powder contains betulin as the major compound, but also betulinic acid, lupeol, erythrodiol and oleanolic acid. We have found that this TE is able to form an oleogel, thus providing an opportunity for the topical application of pharmacologically relevant amounts of triterpenes. Furthermore, we have investigated the TE in comparison to its major isolated compounds in cell culture experiments with human immortalized keratinocytes and skin cancer cells. We could demonstrate dose-dependent cytotoxic and apoptosis-inducing effects of TE and betulin. These experimental data support the notion from a previous clinical study that TE from the outer bark of birch might represent a new tool for the topical treatment of skin cancer and skin cancer precursors like actinic keratoses.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Anticonvulsant and behavioral actions of triterpene isolated from Rubia cordifolia Linn.

Effect of a triterpene isolated from the acetone soluble part of petroleum ether extract of R. cordifolia was studied on convulsions induced by maximum electro shock (MES), electrical kindling and various chemoconvulsants in rats and mice. The effect of triterpene was also investigated on behavior and gamma-aminobutyric acid (GABA) and serotonin (5-HT) content in mouse brain. Triterpene inhibited seizures induced by MES, electrical kindling, pentylenetetrazol (PTZ), and lithium-pilocarpine. However, seizures induced by strychnine were not inhibited. Triterpene reduced locomotion as well as rearing. Pentobarbitone induced sleep was potentiated and amphetamine induced stereotypy was inhibited. The triterpene was found to possess anxiogenic activity. Brain GABA and 5-HT contents were raised by the compound. The study suggests that the triterpene isolated from R. cordifolia bear a potential for further study.

Animals↗
PubMed2006

[Antitumor effects of novel triterpene from Celastrus hypoleucus on human colorectal cancer cell line RKO in vitro].

OBJECTIVE: To investigate the effects of novel triterpene (12-oleanene-3beta, 6alpha-diol) from Celastrus hypoleucus on the proliferation and apoptosis of human colorectal cancer cell line RKO. METHOD: The inhibitory effect of the novel triterpene on RKO cell proliferation was assayed by MTT dye reduction. The morphology of apoptotic cells was observed with AO/EB double fluorescence staining and HE staining, DNA fragment with electrophoresis on agarose gels, sub-diploid peak and cell cycle with flow cytometer (FCM). RESULT: Novel triterpene (12-oleanene-3beta, 6alpha-diol) from C. hypoleucus significantly inhibited proliferation of RKO cells in dose-dependent and time-dependent manner, the IC50 was (12.20 +/- 0.79) microg x mL(-1) at 48 h. Typical apoptotic changes were observed in RKO cells under the fluorescence microscope and the light microscope. DNA ladder was detected on agarose gels at concentrations from 10 microg x mL(-1) to 20 microg x mL(-1) at 48 h. With FCM methods, dose-dependent apoptosis-induced effect was observed in RKO cell line after treatment of triterpene for 48 h, and the apoptotic rates were increased from(2.93 +/- 0.84) % to (50.79 +/- 6.61) % at concentrations from 2.5 microg x mL(-1) to 20 microg x mL(-1). DNA histograms data from FCM analysis showed that the number of cells was obviously reduced during G0-G1 phase and G2-M phase, but not during S phase for RKO cell line after treatment with various concentrations of the triterpene for 48 hours. CONCLUSION: Novel triterpene (12-oleanene-3beta, 6alpha-diol) from C. hypoleucus can induce apoptosis and has inhibition effect on the proliferation in RKO cell line.

Antineoplastic Agents, Phytogenic↗
PubMed1994

Activation of human platelet phospholipases C and A2 by various oxygenated triterpenes.

Eight structural analogues of oxygenated triterpenes exerted striking differences in activation of human platelets. They are four pairs of stereoisomers and two pairs of positional isomers with varying: 1) acetoxyl/hydroxyl substituents; 2) the position of the substituents at C-3 and C-15; and 3) the stereochemistry of a substituent at C-3. It required a threshold concentration for each agent to cause the concentration-dependent activation. These triterpenes were hydrophobic with < 20% difference in the partition coefficients between 1-octanol and water. They caused differential effects on: inositol triphosphate production; the increase in [Ca2+]i; diacylglycerol formation; phosphatidic acid accumulation, protein phosphorylations and arachidonate release. These agents activated both phospholipases C and A2. The trend of activating phospholipase C was triterpenes with two acetoxyl substituents > one acetoxyl/one hydroxyl substituents > two hydroxyl substituents. In activating phospholipase A2, triterpenes with two acetoxyl substituents were most effective, whereas the paired isomers with a hydroxyl group at C-15 alpha and an acetoxyl substituent at C-3 failed the activation. The results enable one to discuss the possible structure-activity relationship of various oxygenated triterpenes in the activation of both phospholipases C and A2.

Arachidonic Acid↗
PubMed2003

Molecular cloning and characterization of triterpene synthases from Medicago truncatula and Lotus japonicus.

Cloning of OSCs required for triterpene synthesis from legume species that are amenable to molecular genetics will provide tools to address the importance of triterpenes and their derivatives during normal plant growth and development and also in interactions with symbionts and pathogens. Here we report the cloning and characterization of a total of three triterpene synthases from the legume species Medicago truncatula and Lotus japonicus. These include a beta-amyrin synthase from M. truncatula (MtAMY1) and a mixed function triterpene synthase from Lotus japonicus (LjAMY2). A partial cDNA predicted to encode a beta-amyrin synthase (LjAMY1) was also isolated from L. japonicus. The expression patterns of MtAMY1, LjAMY1 and LjAMY2 and of additional triterpene synthases previously characterised from M. truncatula and pea differ in different plant tissues and during nodulation, suggesting that these enzymes may have distinct roles in plant physiology and development.

Amino Acid Sequence↗
PubMed2000

Effect of plant sterols from rice bran oil and triterpene alcohols from sheanut oil on serum lipoprotein concentrations in humans.

BACKGROUND: Intake of unsaponifiable compounds from edible oils, such as plant sterols, can lower serum cholesterol concentrations in humans. However, little is known about effects of other chemically related unsaponifiables in edible oils, such as triterpene alcohols. OBJECTIVE: We studied the effects of plant sterols from rice bran oil and triterpene alcohols from sheanut oil on cholesterol concentrations in healthy, normolipemic volunteers. DESIGN: Twenty-eight men and 32 women consumed 29 g/d of 3 margarines for 3 wk each on a crossover, double-blind basis. A margarine based on sunflower oil was used as the control. Concentrates of plant sterols from rice bran oil or triterpene alcohols from sheanut oil were added to make 2 experimental margarines with the same fatty acid composition as the control margarine. RESULTS: Intake of 2.1 g plant sterols/d from rice bran oil decreased total cholesterol by 0.19 mmol/L (95% CI: -0.31, -0.07 mmol/L) and LDL cholesterol by 0.20 mmol/L (95% CI: -0.30, -0.10 mmol/L). HDL-cholesterol and triacylglycerol concentrations did not change significantly. Intake of 2.6 g triterpene alcohols/d from sheanut oil did not significantly affect lipoprotein concentrations in all subjects combined. CONCLUSIONS: We found that 2.1 g plant sterols/d from rice bran oil lowered serum total cholesterol by 5% and LDL cholesterol by 9% in normolipemic humans, whereas triterpene alcohols from sheanut oil did not significantly affect lipoprotein concentrations in all subjects combined. The effect of rice bran oil sterols is probably due to ss-sitosterol and other 4-desmethylsterols and not to 4,4'-dimethylsterols.

Adolescent↗
PubMed2004

[Comparative study on triterpenes in different Ganoderma species].

The triterpene profiles of different Ganoderma products was analysed by HPLC. The results showed that the seven-day fermented mycelia had little triterpene and different growth stages fruiting bodies almost had changeless triterpene. Compared with the fruiting body, the triterpene level of spore was lower. Among different Ganoderma species, Ganoderma atrum had little triterpenes too.

Chromatography, High Pressure Liquid↗
PubMed1994

Antiarthritic mechanisms of amyrin triterpenes.

The triterpenes, alpha-amyrin (AA) and its palmitate (AAP) and linoleate esters (AAL), were tested on models of inflammatory and destructive arthritic processes and their effects were compared with the clinical antiarthritic drugs indomethacin (IN) and methotrexate (MTX). The triterpenes had no effect on the prostaglandin phase of carrageenin pedal edema in rats, which was reduced 28% by 100 microM IN. AAL caused a considerable reduction in the synthesis by human neutrophils of 5-lipoxygenase products--5-HETE (IC50 = 70 microM), LTB4, (62 microM), isomer I (30 microM) and isomer II (24 microM). Rat osteosarcoma cell growth was inhibited by all triterpenes with IC50's (microM) of < 10 (AAP), 14 (AA) and 27 (AAL) and were more effective than IN (35). MTX caused 100% inhibition at a concentration of 10 microM compared with 64% inhibition by AAP. Tadpole collagenase digestion of type I (bone) native collagen was completely inhibited by all the triterpenes as well as IN and MTX at 100 microM. The results indicate that the principal point of antiarthritic intervention by amyrin triterpenes lies in their local inhibition of joint destruction.

Animals↗
PubMed2004

Enhanced triterpene and phytosterol biosynthesis in Panax ginseng overexpressing squalene synthase gene.

Roots of Panax ginseng, one of the most famous medicinal plants, contain various phytosterols and bioactive triterpene saponins (ginsenosides). In P. ginseng, phytosterols and triterpenes share the common biosynthetic intermediate, squalene. Here, we investigate the regulatory role of Panax ginseng squalene synthase (PgSS1) on the biosynthesis of phytosterols and triterpene saponins. PgSS1 transcripts are expressed ubiquitously in the various plant tissues, but higher in shoot apex and root. The transcript levels of PgSS1 increased markedly in the adventitious roots during 12- to 96-h period after metyl jasmonate (MeJA) treatment; MeJA treatment induced the activation of the transcripts of squalene epoxidase (SE), beta-amyrin synthase (bAS), but not cycloartenol synthase (CAS). Unlike MeJA treatment, overexpression of PgSS1 in adventitious roots of transgenic P. ginseng was followed by the up-regulation of all the downstream genes tested, such as SE, bAS, and CAS. The enhanced activity of PgSS1 enzyme resulted in remarkable increase of phytosterols as well as ginsenoside contents. These results demonstrate that PgSS1 is a key regulatory enzyme not only for phytosterol but also for triterpene biosynthesis and overexpressing of PgSS1 confers the hyperproduction of triterpene saponins to P. ginseng.

Acetates↗
PubMed2005

Dammarane triterpenes from the hypocotyls and fruits of Ceriops tagal.

Three new dammarane triterpenes, cereotagaloperoxide, cereotagalol A, and cereotagalol B, together with four known dammarane triterpenes, an oleanane triterpene, and 13 known lupane triterpenes were isolated from the hypocotyls and fruits of Ceriops tagal. The structures of 1-3 were characterized on the basis of their spectroscopic data.

Fruit↗
PubMed1999

Antimicrobial triterpenes from Ilex integra and the mechanism of antifungal action.

Antimicrobial triterpenes were isolated from the fruits of Ilex integra. Their structures were elucidated by spectral data and identified as rotundic acid (1), ulsolic acid (2) and peduncloside (3). Triterpene 1 showed significantly broad antimicrobial activity against bacteria, yeast and filamentous fungi. The antifungal activity of 1 was reversed by fatty acids. Cellular constituents leaked from Candida albicans cells incubated with triterpene 1. These results suggest that the antimicrobial activity of triterpenes in I. integra is due to a change of membrane permeability arising from membrane lipid alteration.

Antifungal Agents↗
PubMed1982

Herbal remedies of the Maritime Indians: sterols and triterpenes of Achillea millefolium L. (Yarrow).

As part of ongoing studies of the medicinal aspects of Maritime flora, particularly the herbal remedies of the Micmac and Malecite Indians, the sterols and triterpenes of Achillea millefolium L. (Compositae), a widely used herbal remedy known commonly as yarrow, were determined. Using modern techniques, including nuclear magnetic resonance spectroscopy and combined GC-mass spectrometry, beta-sitosterol was identified as the major sterol and alpha-amyrin as the major triterpene of this plant. The sterols stigmasterol, campesterol, and cholesterol and the triterpenses beta-amyrin, taraxasterol, and pseudotaraxasterol were also identified. Successful therapeutic application of yarrow may be partly due to the presence of one or more of these compounds since many sterols and triterpenes exhibit a wide range of pharmacological activities. This is the first reported occurrence of cholesterol, campesterol, and the four triterpenes in yarrow.

Canada↗
PubMed2002

Triterpenes from Agarista mexicana as potential antidiabetic agents.

Hypoglycaemic activity-guided fractionation together with chemical analysis led to the isolation of 12-ursene and a novel triterpene 23,24 dimethyl-24-ethyl-stigmast-25-ene from the chloroform extract of the dried stem of A. mexicana. Identification was based on spectroscopic methods. The isolated triterpenes were tested for hypoglycaemic activity in normal and alloxman-diabetic CD1 mice 25-30 g at a dose of 50 mg/kg body weight. The blood glucose levels were determined before and 1.5, 3, 4.5 and 24 h after intraperitoneal drug administration. The results showed that the triterpenes produced a significant hypoglycaemic effect in normal as well as in diabetic mice. Comparison was made between the action of the triterpenes and a known hypoglycaemic drug, tolbutamide (50 mg/kg). The 12-ursene was found to be slow and less effective than tolbutamide, and the 23,24 dimethyl-24-ethyl-stigmast-25-ene was shown to be more effective than tolbutamide.

Animals↗
PubMed2003

Recycling plant wax constituents for chemical defense: hemi-biosynthesis of triterpene saponins from beta-amyrin in a leaf beetle.

Several species of Doryphorina leaf beetles from Central- and South America produce oleanane triterpene glycosides in their defensive glands. The presence of pentacyclic triterpenes in insects is intriguing since they lack the key enzymes necessary to synthesize these compounds. Since beta-amyrin is a common constituent of leaf waxes, we hypothesized that these leaf beetles use this compound as a precursor to their oleanane glycosides. To test this hypothesis we first confirmed the presence of beta-amyrin in Ipomoea batatas, the food plant of Platyphora kollari. Next, adults of P. kollari were fed for 10 days with I. batatas leaf disks painted with a solution of [2,2,3-(2)H(3)]beta-amyrin ([2,2,3-(2)H(3)]-1). The secretion from their defensive glands was collected and analyzed by HPLC-ESIMS. The results demonstrated that the secretion of beetles fed with an amount of [2,2,3-(2)H(3)]beta-amyrin corresponding to the quantity of unlabeled (natural) beta-amyrin present in the leaf disks contained on average 5.1% of [2,2,3-(2)H(3)]-3- O-beta- d-glucopyranosyl-(1-->4)-beta- d-glucuronopyranosyl-hederagenin ([2,2,3-(2)H(3)]-2), whereas the secretions of beetles fed with 10 times this amount of [2,2,3-(2)H(3)]beta-amyrin contained on average 23.9% of [2,2,3-(2)H(3)]-2. In both series of experiments, the percentage of labeled versus unlabeled triterpene glycoside in the secretion was positively correlated with the amount of deuterated beta-amyrin ingested. These results demonstrate for the first time that some leaf beetles are able to metabolize a widespread triterpenic constituent of leaf wax into more complex glycosides that are stored in their defensive glands.

Animals↗