Cycloartanol

Identification and Characterization of Sterol Acyltransferases Responsible for Steryl Ester Biosynthesis in Tomato.[Pubmed:29868054]

Front Plant Sci. 2018 May 8;9:588.

Steryl esters (SEs) serve as a storage pool of sterols that helps to maintain proper levels of free sterols (FSs) in cell membranes throughout plant growth and development, and participates in the recycling of FSs and fatty acids released from cell membranes in aging tissues. SEs are synthesized by sterol acyltransferases, a family of enzymes that catalyze the transfer of fatty acil groups to the hydroxyl group at C-3 position of the sterol backbone. Sterol acyltransferases are categorized into acyl-CoA:sterol acyltransferases (ASAT) and phospholipid:sterol acyltransferases (PSAT) depending on whether the fatty acyl donor substrate is a long-chain acyl-CoA or a phospolipid. Until now, only Arabidopsis ASAT and PSAT enzymes (AtASAT1 and AtPSAT1) have been cloned and characterized in plants. Here we report the identification, cloning, and functional characterization of the tomato (Solanum lycopersicum cv. Micro-Tom) orthologs. SlPSAT1 and SlASAT1 were able to restore SE to wild type levels in the Arabidopsis psat1-2 and asat1-1 knock-out mutants, respectively. Expression of SlPSAT1 in the psat1-2 background also prevented the toxicity caused by an external supply of mevalonate and the early senescence phenotype observed in detached leaves of this mutant, whereas expression of SlASAT1 in the asat1-1 mutant revealed a clear substrate preference of the tomato enzyme for the sterol precursors cycloartenol and 24-methylene Cycloartanol. Subcellular localization studies using fluorescently tagged SlPSAT1 and SlASAT1 proteins revealed that SlPSAT1 localize in cytoplasmic lipid droplets (LDs) while, in contrast to the endoplasmic reticulum (ER) localization of AtASAT1, SlASAT1 resides in the plasma membrane (PM). The possibility that PM-localized SlASAT1 may act catalytically in trans on their sterol substrates, which are presumably embedded in the ER membrane, is discussed. The widespread expression of SlPSAT1 and SlASAT1 genes in different tomato organs together with their moderate transcriptional response to several stresses suggests a dual role of SlPSAT1 and SlASAT1 in tomato plant and fruit development and the adaptive responses to stress. Overall, this study contributes to enlarge the current knowledge on plant sterol acyltransferases and set the basis for further studies aimed at understanding the role of SE metabolism in tomato plant growth and development.

Psychotria viridis: Chemical constituents from leaves and biological properties.[Pubmed:28640347]

An Acad Bras Cienc. 2017 Apr-Jun;89(2):927-938.

The phytochemical study of hexane, chloroform and methanol extracts from leaves of Psychotria viridis resulted in the identification of: the pentacyclic triterpenes, ursolic and oleanolic acid; the steroids, 24-methylene-Cycloartanol, stigmasterol and beta-sitosterol; the glycosylated steroids 3-O-beta-D-glucosyl-beta-sitosterol and 3-O-beta-D-glucosyl-stigmasterol; a polyunsaturated triterpene, squalene; the esters of glycerol, 1-palmitoylglycerol and triacylglycerol; a mixture of long chain hydrocarbons; the aldehyde nonacosanal; the long chain fat acids hentriacontanoic, hexadecanoic and heptadenoic acid; the ester methyl heptadecanoate; the 4-methyl-epi-quinate and two indole alkaloids, N,N-dimethyltryptamine (DMT) and N-methyltryptamine. The chemical structures were determined by means of spectroscopic (IR, 1H and 13C NMR, HSQC, HMBC and NOESY) and spectrometric (CG-MS and LCMS-ESI-ITTOF) methods. The study of biologic properties of P. viridis consisted in the evaluation of the acetylcholinesterase inhibition and cytotoxic activities. The hexane, chloroform, ethyl acetate and methanol extracts, the substances 24-methylene-Cycloartanol, DMT and a mixture of 3-O-beta-D-glucosyl-beta-sitosterol and 3-O-beta-D-glucosyl-stigmasterol showed cholinesterase inhibiting activity. This activity induced by chloroform and ethyl acetate extracts was higher than 90%. The methanol and ethyl acetate extracts inhibit the growth and/or induce the death of the tumor cells strains B16F10 and 4T1, without damaging the integrity of the normal cells BHK and CHO. DMT also demonstrated a marked activity against tumor cell strains B16F10 and 4T1.

A new oxo-sterol derivative from the rhizomes of Costus speciosus.[Pubmed:28480734]

Nat Prod Res. 2018 Jan;32(1):18-22.

Chemical investigation of the rhizomes of Costus speciosus led to the isolation of a new compound, 22-ketocholesteryl palmitate (1) along with four known compounds, 24-methyleneCycloartanol (2), Cycloartanol (3), stigmasterol (4) and linoleic acid (5). The structure of new compound was characterised by extensive 1D-, 2D-NMR and mass spectrometry (GC-MS and HR-ESI-MS) techniques.

Triterpene alcohols and sterols from rice bran reduce postprandial hyperglycemia in rodents and humans.[Pubmed:26935127]

Mol Nutr Food Res. 2016 Jul;60(7):1521-31.

SCOPE: Hyperglycemia is a major public health problem worldwide and there is increasing demand for prevention of postprandial hyperglycemia in diabetic, prediabetic, and healthy humans. METHODS AND RESULTS: We investigated whether rice bran and triterpene alcohol and sterol preparation (TASP) lowered hyperglycemia in mice and humans. Brown rice and white rice supplemented with TASP lowered the postprandial hyperglycemia in humans. TASP and its components (cycloartenol [CA], 24-methylene Cycloartanol, beta-sitosterol, and campesterol) decreased postprandial hyperglycemia in C57BL/6J mice. Glucose transport into everted rat intestinal sacs and human HuTu80 cells transfected with sodium-glucose cotransporter-1 (SGLT1) was significantly reduced by the addition of CA. Intracellular localization analysis suggested that SGLT1 translocation to the apical plasma membrane was inhibited when the cells were treated with CA. CONCLUSIONS: We demonstrated for the first time that TASP from rice bran lowered postprandial hyperglycemia in mice and humans. The smaller increase in blood glucose following TASP consumption may be due to the CA-induced decrease in glucose absorption from the intestine, which may be related to decreased membrane translocation of SGLT1.

Cycloartane Triterpenes from the Aerial Parts of Actaea racemosa.[Pubmed:26760374]

J Nat Prod. 2016 Mar 25;79(3):541-54.

Investigating the phytochemical equivalence of the aerial parts of Actaea racemosa (syn. Cimicifuga racemosa) relative to the widely used roots/rhizomes, this study provides a perspective for the potential use of renewable ("green") plant parts as a source of black cohosh botanical preparations. In addition to the characterization of Nomega-methylserotonin as one representative marker of the Actaea alkaloids, nine cycloartane triterpenes were isolated and characterized, including the two new triterpene glycosides (1S,15R)-1,15,25-trihydroxy-3-O-beta-d-xylopyranosyl-acta-(16S,23R,24R)-16,23;16, 24-binoxoside (1) and 3-O-alpha-l-arabinopyranosyl-(1S,24R)-1,24,25-trihydroxy-15-oxo-acta-(16R,23R)-16 ,23-monoxoside (2). Their structures were elucidated by spectroscopic data interpretation. The relative configuration of 1 was deduced by (1)H iterative full-spin analysis (HiFSA), making it the first example of the complete analysis of the complex (1)H NMR spectrum of a triterpene glycoside. In addition to the new compounds 1 and 2, the aerial plant parts were shown to contain the previously known binoxosides 3, 4, 6, and 7, the monoxoside 8, and the binoxols 5 and 9. Overall, the metabolome of the aerial plant parts consists of a variety of Actaea triterpenes, similar to those found in roots/rhizomes, a tendency toward C-1 and C-7 hydroxylation of the Cycloartanol skeleton, a greater abundance of aglycones, and the presence of comparable amounts of Nomega-methylserotonin.

Sterols and squalene in apricot (Prunus armeniaca L.) kernel oils: the variety as a key factor.[Pubmed:26745662]

Nat Prod Res. 2017 Jan;31(1):84-88.

The profile of sterols and squalene content in oils recovered from the kernels of 15 apricot (Prunus armeniaca L.) varieties were investigated. Nine sterols (campesterol, beta-sitosterol, Delta5-avenasterol, 24-methylene-Cycloartanol, cholesterol, gramisterol, Delta7-stigmasterol, Delta7-avenasterol and citrostadienol) were identified in apricot kernel oils. The beta-sitosterol was the predominant sterol in each cultivar and consisted of 76-86% of the total detected sterols. The content of total sterols and squalene were significantly affected by the variety and ranged between 215.7-973.6 and 12.6-43.9 mg/100 g of oil, respectively.

Unveiling the anti-inflammatory activity of Sutherlandia frutescens using murine macrophages.[Pubmed:26585972]

Int Immunopharmacol. 2015 Dec;29(2):254-262.

Sutherlandia frutescens is a botanical widely used in southern Africa for treatment of inflammatory and other conditions. Previously, an ethanolic extract of S. frutescens (SFE) has been shown to inhibit the production of reactive oxygen species (ROS) and nitric oxide (NO) by murine neurons and a microglia cell line (BV-2 cells). In this study we sought to confirm the anti-inflammatory activities of SFE on a widely used murine macrophage cell line (i.e., RAW 264.7 cells) and primary mouse macrophages. Furthermore, experiments were conducted to investigate the anti-inflammatory activity of the flavonol and Cycloartanol glycosides found in high quantities in S. frutescens. While the SFE exhibited anti-inflammatory activities upon murine macrophages similar to that reported with the microglia cell line, this effect does not appear to be mediated by sutherlandiosides or sutherlandins. In contrast, chlorophyll in our extracts appeared to be partly responsible for some of the activity observed in our macrophage-dependent screening assay.

Unsaponifiable Fraction of Unripe Fruits of Olea europaea: An Interesting Source of Anti-inflammatory Constituents.[Pubmed:26544118]

Planta Med. 2016 Feb;82(3):273-8.

The unsaponifiable fraction of olive oil from unripe fruits of Olea europaea at different stages of maturation (from 20 to 32 weeks after flowering) was analyzed by gas chromatography-mass spectrometry in order to select the time associated to the unsaponifiable fraction with the maximal yield in bioactive constituents. According to quantitative gas chromatography-mass spectrometry analysis, the unsaponifiable fraction (2.46% of the total oil) from olive fruits at the 22nd week was found to contain the maximal yield in anti-inflammatory constituents. Its composition was lanosterol (2.60 mg/g oil), stigmasterol (2.15), Cycloartanol acetate (2.04), stigmastan-3,5-diene (2.01), obtusifoliol (1.93), cholesta-4,6-dien-3-one (1.42), alpha-amyrin (1.42), alpha-tocopherol (1.32), squalene (1.02), beta-amyrin (0.57), and beta-sitosterol (0.22). At later times, there was a decrease in the quantitative unsaponifiable fraction yield and a qualitative shift in the bioactive constituents. The 22nd week unsaponifiable fraction was subsequently incorporated into a topical preparation to be utilized for a small pilot clinical study in five patients affected by osteoarthrosis. According to clinical observation, the application of the ointment (three times daily for three weeks) attenuated hand and knee joint inflammatory features in all patients and was not associated to any adverse reactions.

Triterpene alcohols and sterols from rice bran lower postprandial glucose-dependent insulinotropic polypeptide release and prevent diet-induced obesity in mice.[Pubmed:25257874]

J Appl Physiol (1985). 2014 Dec 1;117(11):1337-48.

Obesity is now a worldwide health problem. Glucose-dependent insulinotropic polypeptide (GIP) is a gut hormone that is secreted following the ingestion of food and modulates energy metabolism. Previous studies reported that lowering diet-induced GIP secretion improved energy homeostasis in animals and humans, and attenuated diet-induced obesity in mice. Therefore, food-derived GIP regulators may be used in the development of foods that prevent obesity. Rice bran oil and its components are known to have beneficial effects on health. Therefore, the aim of the present study was to clarify the effects of the oil-soluble components of rice bran on postprandial GIP secretion and obesity in mice. Triterpene alcohols [cycloartenol (CA) and 24-methylene Cycloartanol (24Me)], beta-sitosterol, and campesterol decreased the diet-induced secretion of GIP in C57BL/6J mice. Mice fed a high-fat diet supplemented with a triterpene alcohol and sterol preparation (TASP) from rice bran for 23 wk gained less weight than control mice. Indirect calorimetry revealed that fat utilization was higher in TASP-fed mice than in control mice. Fatty acid oxidation-related gene expression in the muscles of mice fed a TASP-supplemented diet was enhanced, whereas fatty acid synthesis-related gene expression in the liver was suppressed. The treatment of HepG2 cells with CA and 24Me decreased the gene expression of sterol regulatory element-binding protein (SREBP)-1c. In conclusion, we clarified for the first time that triterpene alcohols and sterols from rice bran prevented diet-induced obesity by increasing fatty acid oxidation in muscles and decreasing fatty acid synthesis in the liver through GIP-dependent and GIP-independent mechanisms.

Changes in the triterpenoid content of cuticular waxes during fruit ripening of eight grape (Vitis vinifera) cultivars grown in the Upper Rhine Valley.[Pubmed:25058466]

J Agric Food Chem. 2014 Aug 13;62(32):7998-8007.

Triterpenoids present in grape cuticular waxes are of interest due to their potential role in protection against biotic stresses, their impact on the mechanical toughness of the fruit surface, and the potential industrial application of these biologically active compounds from grape pomace. The determination of the triterpenoid profile of cuticular waxes reported here supplements existing knowledge of the chemical diversity of grape, with some compounds reported in this species for the first time. Common compounds identified in eight examined cultivars grown in the Upper Rhine Valley include oleanolic acid, oleanolic and ursolic acid methyl esters, oleanolic aldehyde, alpha-amyrin, alpha-amyrenone, beta-amyrin, Cycloartanol, 24-methyleneCycloartanol, erythrodiol, germanicol, lupeol accompanied by lupeol acetate, campesterol, cholesterol, sitosterol, stigmasterol, and stigmasta-3,5-dien-7-one, whereas 3,12-oleandione was specific for the Muscat d'Alsace cultivar. Changes in the triterpenoid content of cuticular waxes were determined at three different phenological stages: young grapes, grapes at veraison (the onset of ripening), and mature grapes. The results reveal a characteristic evolution of triterpenoid content during fruit development, with a high level of total triterpenoids in young grapes that gradually decreases with a slight increase in the level of neutral triterpenoids. This phenomenon may partially explain changes in the mechanical properties of the cuticle and possible modulations in the susceptibility to pathogens of mature grapes.

[Network pharmacology study on major active compounds of siwu decoction analogous formulae for treating primary dysmenorrhea of gynecology blood stasis syndrome].[Pubmed:24754179]

Zhongguo Zhong Yao Za Zhi. 2014 Jan;39(1):113-20.

OBJECTIVE: To explore the molecular mechanisms of main active ingredients of Siwu decoction analogous formulae for treating primary dysmenorrhea of gynecology blood stasis syndrome by network pharmacology study, and to investigate the correlations between multi-compounds, multi targets and multi pathways. METHOD: Major active compounds from Siwu decoction analogous formulae, including ligustilide, butylidene phthalide, senkyunolide, ferulic acid, gallic acid, peoniflorin, jioglutin A, catalpol, transanethole, zingiberone, commiphoric acid, eugenol, isorhamnetin-3-O-neohesperidoside, wulingzhic acid, alpha-cyperone, cyperene, costunolide, costic acid, tetrahydropalmatine, protopine, amygdalin, 24-methylene Cycloartanol, oleic acid, linoleic acid, 3-p-coumaroylquinic acid, hydroxysafflor yellow A, coptisine, berberine, jatrorrhizine, baicalein, baicalin, wogonin were collected to build component-protein networks based on PharmMapper database. The targets information access was used to construct and visualize components-targets-pathways network model using the kyoto encyclopedia of genes and genomes (KEGG) pathway database and Cytoscape software. RESULT AND CONCLUSION: Serine threonine protein kinases play an important role in the process of cells. They were potential targets in the effect of Siwu decoction analogous formulae. The effect of main active ingredients involved 51 the pathway. Besides the same ones, Shaofu Zhuyu decoction had more effect on lipid metabolism, Xiangfu Siwu decoction on amino acid metabolism pathways, Taohong Siwu decoction on carbohydrate metabolism, while, Qinlian Siwu decoction on ErbB, VEGF signal transduction pathway. Siwu decoction and its derived formulae not only had common targets and pathways, but also had their own emphasis. This reflected the formulae effect mode of multi-ingredients, multi-targets and multi-pathways. It may provide clues to deeper study of molecular mechanism of Siwu decoction analogous formulae action.

Triterpenoid content of berries and leaves of bilberry Vaccinium myrtillus from Finland and Poland.[Pubmed:23157739]

J Agric Food Chem. 2012 Dec 5;60(48):11839-49.

Triterpenoid compounds found in free and ester forms in extracts of entire fruits and leaves and in fruit and leaf cuticular waxes of bilberry (Vaccinium myrtillus L.) collected in Finland and Poland were identified and quantitated by gas chromatography-mass spectrometry coupled to a flame ionization detector (GC-MS/FID). The main bilberry triterpenoid profile consisted of alpha- and beta-amyrin, alpha- and beta-amyrenone, campesterol, cholesterol, citrostadienol (in berries), Cycloartanol, erythrodiol, lupeol, 24-methyleneCycloartanol, sitosterol, sitostanol, stigmasterol, stigmasta-3,5-dien-7-one, uvaol, oleanolic and ursolic aldehydes, and oleanolic, ursolic, 2alpha-hydroxyoleanolic, and 2alpha-hydroxyursolic acids. Friedelin and D:A-friedooleanan-3beta-ol were found only in Finnish plants, whereas D:C-friedours-7-en-3beta-ol and taraxasterol were found only in Polish plants. To our knowledge, this is the first thorough description of triterpenoid compounds in this species. The presented results revealed that the triterpenoid profile of bilberry varied considerably between different organs of the plant, regardless of the plant origin, as well as between plant samples obtained from the two geographical locations.

Triterpenoid profile of flower and leaf cuticular waxes of heather Calluna vulgaris.[Pubmed:23148482]

Nat Prod Res. 2013 Aug;27(15):1404-7.

Analysis of the main triterpenoid profile of chloroform-soluble cuticular waxes of heather flowers and leaves by GC-MS revealed the following composition: five triterpene acids - betulinic, oleanolic, ursolic, 3-oxo-olean-12-en-28-oic and 3-oxo-ursan-12-en-28-oic; eight monohydroxyalcohols - alpha-amyrin, beta-amyrin, Cycloartanol, 24-methyleneCycloartanol, friedelinol, germanicol, lupeol and taraxasterol; three dihydroxyalcohols - betulin, erythrodiol and uvaol; two aldehydes - oleanolic and ursolic; four ketones - alpha-amyrenone, 4-epi-friedelin, friedelin and taraxerone and seven steroids - campesterol, cholesterol, sitostanol, sitosterol, stigmasterol, stigmasta-3,5-dien-7-one and stigmastane-3,6-dione. Triterpenoids accounted for 20% and 65% by mass of flower and leaf waxes, respectively, which suggest that heather leaves represent a very promising source of these compounds. Ursolic acid was the principal triterpenoid in the cuticular wax of both organs, whereas among the neutral triterpenes, friedelin and uvaol were the most abundant in flowers and leaves, respectively. This report provides the first thorough overview of the triterpenoid composition of cuticular waxes of heather.