Oleanane Triterpene Research Articles

In vivo and in vitro Models of PM2.5 Induced COPD: Focus on the Role of RTA-408.

Inflammation and oxidative stress are important factors in the pathogenesis of Chronic obstructive pulmonary disease (COPD). Current treatments for COPD focus on improving symptoms caused by inflammation rather than curing the disease, therefore, emerging research focusing on upstream pathways may help develop effective treatments. Epidemiological investigations have shown that exposure to fine particulate matter (PM2.5) can cause lung inflammation and oxidative stress through nuclear factor NF-E2-associated factor (Nrf2) pathway, leading to COPD. Nrf2 is an important transcription factor regulating anti-inflammatory and antioxidant stress, and its abnormal expression level or changes in transcriptional activity are related to the occurrence and development of COPD. Omaviloxone - RTA-408, a synthetic oleanane triterpene that acts as an Nrf2 activator, RTA-408 may play an important role in COPD. In this study, PM2.5 was used to establish HBE cell model in vitro and rat model in vivo to simulate COPD, and the effect of Nrf2 activator RTA-408 on PM2.5-induced COPD model and its mechanism were investigated. The HBE cell model in vitro and rat model in vivo were established to simulate COPD, and the effect of RTA-408 on COPD was detected by various experimental methods. The results showed that RTA-408 could activate Nrf2 both in vivo and in vitro. By activating Nrf2/HO-1 pathway, RTA-408 inhibits NF-κB and IFN-γ pathways, alleviates inflammation and oxidative stress of HBE cells in COPD model rats and PM2.5 exposed cells, and plays a therapeutic role in reversing cell damage and delaying disease progression in COPD. In addition, in vitro experiments, silencing Nrf2 eliminated the protective effect of RTA-408 on COPD cell models, which also confirmed the role of RTA-408. We conclude that RTA-408 is well worth considering as a new strategy for the treatment of COPD, and may also have a positive preventive effect.

Characterisation of saponins from Hedera nepalensis in Vietnam northwest mountainous areas with the aid of high-resolution mass spectrometry

This research aims to explore the saponins composition of H. nepalensis in four northwest mountainous areas of Vietnam including Ha Giang, Lai Chau, Lao Cai, and Lang Son with the aid of high-resolution mass spectrometry. As a result, 42 saponins are successfully identified in H. nepalensis leaves by UHPLC‐Q‐TOF-MS/MS analyses, in which two 30-noroleanane and four oleanane triterpene saponins structures have been reported for the first time. Two structures of compound 20 were discovered in four samples. Two structures of compound 8 were found in H. nepalensis from Ha Giang and Lao Cai, while two structures of compound 28 were not observed in Lang Son. Different environmental and climatic circumstances in various places may have an impact on chemical constituents of H. nepalensis. By providing the phytochemicals profile of H. nepalensis leaves, our study supports the orientation for future research on this medicinal plant as well as other Hedera species.

Oleanane-type triterpenoid sulphates, two new α-glucosidase inhibitors from Elaeocarpus hainanensis

In connection with our interest in the phytochemical investigation of Elaeocarpus hainanensis Oliv. (Elaeocarpaceae) growing in Vietnam, two new sulphated oleanane triterpenes were obtained herein and structurally identified. Based on the combination of the extensive 1D-, 2D NMR and HR ESI MS spectroscopic data analysis, their chemical structures have been elucidated as 1α,3β-dihydroxy-olean-18-ene 1-sulphate (1) and 1α,3β-dihydroxy-olean-12-ene 1-sulphate (2). Notably, compounds 1 and 2 are corroborating the proposition that triterpenoid sulphates serve as chemosystematic markers of the Elaeocarpus genus. Additionally, all these two new compounds 1 and 2 strongly inhibited α-glucosidase in vitro with the respective IC50 values of 3.81 ± 0.33 µM and 21.27 ± 0.48 µM, which were significantly better than that obtained from positive control, acarbose (IC50 247.73 ± 11.85 µM).

A New Oleanane Triterpene with Allelopathic Activity from Lantana camara

A New Oleanane Triterpene with Allelopathic Activity from Lantana camara

Chryroxosides A–E: five new triterpene saponins from the leaves of Chrysophyllum roxburghii G.Don. and their cytotoxic activity

Five undescribed oleanane triterpene glycosides named chryroxosides A–D (1–5), together with five known compounds (6–10) were isolated from the leaves of Chrysophyllum roxburghii G.Don. Their chemical structures were elucidated by extensive spectroscopic data analyses including IR, HR-ESI-MS, 1D and 2D NMR). Compounds 1, 3, and 5 showed cytotoxic effects against KB, HepG2, HL60, P388, HT29, and MCF7 cell lines with the IC50 values ranging from 14.40 to 52.63 μM compared to the positive control compound (ellipticine) with the IC50 values ranging from 1.34 to 1.99 μM.

Five New Oleanane Triterpene Saponins from Camellia petelotii and their Alpha-glucosidase Inhibitory Activity.

Five new triterpenoid glycosides, named campetelosides A-E (1-5), together with three known compounds, chikusetsusaponin IVa (6), umbellatoside B (7), and silvioside E (8) were isolated from the leaves of Camellia petelotii (Merr.) Sealy. Their chemical structures were determined by interpretations of HR-ESI-MS and NMR spectra. In addition, compounds 1-8 were evaluated for their α-glucosidase inhibitory effects. Compounds 1-3 significantly showed α-glucosidase inhibitory activity with IC50 values of 166.7 ± 6.0, 45.9 ± 2.6, and 395.3 ± 10.5 μM, respectively, compared to that of the positive control, acarbose, with an IC50 value of 200.4 ± 10.5 μM.

Assessing the Effectiveness of Chemical Marker Extraction from Amazonian Plant Cupuassu (Theobroma grandiflorum) by PSI-HRMS/MS and LC-HRMS/MS.

Employing a combination of liquid chromatography electrospray ionization and paper spray ionization high-resolution tandem mass spectrometry, extracts from cupuassu (Theobroma grandiflorum) pulp prepared with either water, methanol, acetonitrile or combinations thereof were subjected to metabolite fingerprinting. Among the tested extractors, 100% methanol extracted preferentially phenols and cinnamic acids derivatives, whereas acetonitrile and acetonitrile/methanol were more effective in extracting terpenoids and flavonoids, respectively. And while liquid chromatography- mass spectrometry detected twice as many metabolites as paper spray ionization tandem mass spectrometry, the latter proved its potential as a screening technique. Comprehensive structural annotation showed a high production of terpenes, mainly oleanane triterpene derivatives. of the mass spectra Further, five major metabolites with known antioxidant activity, namely catechin, citric acid, epigallocatechin-3'-glucuronide, 5,7,8-trihydroxyflavanone, and asiatic acid, were subjected to molecular docking analysis using the antioxidative enzyme peroxiredoxin 5 (PRDX5) as a model receptor. Based on its excellent docking score, a pharmacophore model of 5,7,8-trihydroxyflavanone was generated, which may help the design of new antioxidants.

Chemical constituents from the leaves of Craibiodendron yunnanense and their chemotaxonomic significance

The phytochemical investigation on the leaves of Craibiodendron yunnanense W.W. Smith resulted in the isolation of 21 compounds, including 11 known ursane triterpenes, 8 oleanane triterpenes, and 2 sterols. Their structures were clarified by analyses of their NMR spectroscopic data as well as by comparison of these data with those published in the literature. From the present investigation, compounds 1–2, 6, 8–10, 13–16, 18 and 21 were isolated for the first time from the family Ericaceae, and their chemotaxonomic significance was discussed. Additionally, compounds 21 exhibited in vitro cytotoxicity against human MDA-MB-231 and BT-549 cancer cell lines with IC50 value of 14.19 μM and 21.45 μM, respectively.

Triterpenes and limonoids of Cedrela: Distribution, biosynthesis, and 1 H and 13 C NMR data.

Cedrela genus, a member of the Meliaceae family, presents both chemical characteristics associated with and those that distinguish it from the rest of its members. The presence of triterpenes and limonoids is the characteristic of the Meliaceae family, but the class and type of these chemical constituents are distinctive for each genus. Cedrela includes cycloartane, ursane, oleanane, tirucallane, butyrospermane, and apotirucallane triterpenes, and its limonoids belongs to six class and nine types, known as class Ia-type havanensines, class Ib-type delevoyin, class II-type gedunin, class IIIb-type andirobin, class IIIg-type mexicanolide, class IVa-type evoludone, class Va-type obacunol, class V-type limonin, and class VIII. Each of these structural arrangements includes specific traits, defined by their biosynthetic origin, which can be established by means of structural elucidation techniques, particularly 1 H and 13 C NMR, which assisted by 2D NMR techniques, allowing to deduce their structures unequivocally. The constant presence of these skeletal arrangements in Cedrela ensures that they are its chemophenetic markers and their recurrence is an important criterion for their identity. This review is a compilation of the occurrence of triterpenes and limonoids in Cedrela genus, detailing their biosynthetic association and collecting and organizing their NMR data, with the purpose of facilitating its location, analysis, and use in the phytochemical study of species from this genus.

Growth and Oleanolic Acid Accumulation of Polyscias fruticosa Cell Suspension Cultures.

Oleanolic acid is an oleanane triterpene found in many plant species all over the world. This compound is also a major saponin in leaves of Polyscias fruticosa and possesses several promising pharmacological activities, such as hepatoprotective effects, and antiinflammatory, antioxidant, or anticancer activities. The objective of the present work is to establish cell suspension culture of P. fruticosa, investigate the influence of several factors such as plant growth regulators and carbon source on cell growth, and determine their oleanolic acid content. Cell culture was established by using 2 g fresh weight of 30 day old friable callus derived from in vitro stem segment in 50 mL of liquid medium with a shaking speed of 220 rpm. The culture was then incubated at 25±2ºC with a shaking speed of 120 rpm in the period of 12 h daylight at a light intensity of about 6.75 μmol/m2/s. Cell growth was measured by fresh and dry biomass at 16 h day. Oleanolic acid content was determined using HPLC analysis. The study results showed that MS medium containing 2% sucrose as a carbon source, supplemented with 1 mg/L 6-benzylaminopurine and 0.5 mg/L 2,4-dichlorophenoxyacetic acid was the most appropriate growth medium. Cell biomass and oleanolic acid content reached the highest values of 0.43 g dry weight/flask and 25.4 mg/g dry weight, respectively. These results indicated the potential production of oleanolic acid, a compound with high pharmacological value, from P. fruticosa cell culture.

Tetracyclic and Pentacyclic Triterpenes with High Therapeutic Efficiency in Wound Healing Approaches.

Wounds are among the most common skin conditions, displaying a large etiological diversity and being characterized by different degrees of severity. Wound healing is a complex process that involves multiple steps such as inflammation, proliferation and maturation and ends with scar formation. Since ancient times, a widely used option for treating skin wounds are plant- based treatments which currently have become the subject of modern pharmaceutical formulations. Triterpenes with tetracyclic and pentacyclic structure are extensively studied for their implication in wound healing as well as to determine their molecular mechanisms of action. The current review aims to summarize the main results of in vitro, in vivo and clinical studies conducted on lupane, ursane, oleanane, dammarane, lanostane and cycloartane type triterpenes as potential wound healing treatments.

Screening of Indonesian Edible Plants for Bioactive Constituents and a New Protein Tyrosine Phosphatase 1B Inhibitory Acylbenzene Derivative from Leaves of Indonesian Syzygium polyanthum.

Bioassay screening using Indonesian plants, such as traditional foods (vegetables, spices, and tea) and folk medicinal herbs, identified eight protein tyrosine phosphatase (PTP) 1B inhibitory and two antibacterial plants. The leaves of Syzygium polyanthum (Wight) Walp. were examined in more detail to define PTP1B inhibitory components, resulting in the isolation of a new active acylbenzene (1) along with four related congeners of 1 (2-5) and four oleanane triterpenes (6-9). The structure of 1 was elucidated as 12-oxo-12-(2,3,5-trihydroxy-4-methylphenyl)dodecanoic acid based on its spectroscopic data. The acylbenzenes 1 and 3-5 inhibited PTP1B activity with IC50 values ranging between 9.5 and 14 µM, whereas the triterpenes 7-9 also suppressed this activity with IC50 values of 3.3-5.7 µM.

Antiproliferative activity of new pentacyclic triterpene and a saponin from Gladiolus segetum Ker-Gawl corms supported by molecular docking study.

A new triterpenoidal saponin identified as 3-O-[β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-xylopyranosyl]-2β,3β,16α-trihydroxyolean-12-en-23,28-dioic acid-28-O-α-l-rhamnopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 2)-α-l-arabinopyranoside 1 together with a new oleanane triterpene identified as 2β,3β,13α,22α-tetrahydroxy olean-23,28-dioic acid 2 and 6 known compounds (3–8) have been isolated from Gladiolus segetum Ker-Gawl corms. The structural elucidation of the isolated compounds was confirmed using different chemical and spectroscopic methods, including 1D and 2D NMR experiments as well as HR-ESI-MS. Moreover, the in vitro cytotoxic activity of the fractions and that of the isolated compounds 1–8 were investigated against five human cancer cell lines (PC-3, A-549, HePG-2, MCF-7 and HCT-116) using doxorubicin as a reference drug. The results showed that the saponin fraction exhibited potent in vitro cytotoxic activity against the five human cancer cell lines, whereas the maximum activity was exhibited against the PC-3 and A-549 cell lines with the IC50 values of 1.13 and 1.98 μg mL−1, respectively. In addition, compound 1 exhibited potent activity against A-549 and PC-3 with the IC50 values of 2.41 μg mL−1 and 3.45 μg mL−1, respectively. Interestingly, compound 2 showed the maximum activity against PC-3 with an IC50 of 2.01 μg mL−1. These biological results were in harmony with that of the molecular modeling study, which showed that the cytotoxic activity of compound 2 might occur through the inhibition of the HER-2 enzyme.

Structure-Activity Relationships of Pentacyclic Triterpenoids as Inhibitors of Cyclooxygenase and Lipoxygenase Enzymes.

Pentacyclic triterpenes may be active agents and provide a rich natural resource of promising compounds for drug development. The inhibitory activities of 29 natural oleanane and ursane pentacyclic triterpenes were evaluated against four major enzymes involved in the inflammatory process: 5-LOX, 15-LOX-2, COX-1, and COX-2. It was found that 3-O-acetyl-β-boswellic acid potently inhibited human 15-LOX-2 (IC50 = 12.2 ± 0.47 μM). Analysis of the structure-activity relationships revealed that the presence of a hydroxy group at position 24 was beneficial in terms of both 5-LOX and COX-1 inhibition. Notably, the introduction of a carboxylic acid group at position 30 was important for dual 5-LOX/COX inhibitory activity; furthermore, its combination with a carbonyl group at C-11 considerably increased 5-LOX inhibition. Also, the presence of an α-hydroxy group at C-2 or a carboxylic acid group at C-23 markedly suppressed the 5-LOX activity. The present findings reveal that the types and configurations of polar moieties at positions C-2, -3, -11, -24, and -30 are important structural aspects of pentacyclic triterpenes for their potential as anti-inflammatory lead compounds.

Chemical constituents from the roots of cultivated Ilex pubescens

Phytochemical study of butanol extract from the roots of cultivated Ilex pubescens Hook. et Arn. obtained nine ursane triterpenes (1–9), two oleanane triterpenes (10–11) and three phenylpropanoids (12–14). All of the compounds were determined on the basis of MS and NMR and comparison with literature. Among them, compounds 2 and 13 were isolated from I. pubescens for the first time, of which 13 was a new finding in the Aquifoliaceae family. Our present study exhibited the taxonomic relationships between I. pubescens and other species in genus Ilex and those between Aquifoliaceae and other families. Furthermore, the study suggested the cultivated I. pubescens may be as an alternative for those wild resource collected freshly from mountain.

A new oleanane triterpene from the leaves of Ficus hirta

Repeated column chromatography of the n-hexane extract of Ficus hirta leaves (Moraceae) led to isolation of a new oleanane triterpene, 3β-hydroxy-11-oxo-olean-12-enyl-3-stearate (1) in addition to three known compounds, taraxerol (2), 3β-acetoxy-11α-methoxy-12-ursene (3) and 3β-acetoxy-11α-hydroxy-12-ursene (4). Their structures were elucidated by spectroscopic methods and by comparison with data reported in the literatures.

Chemical constituents from roots and rhizomes of Rubia oncotricha and their cytotoxic activities

Fourteen compounds, including rubiprasin D (1), rubiprasin B (2), rubiprasin C (3), oleanolic acid (4), methyl-5-hydroxy-dinaphtho[1, 2-2'3']furan-7, 12-dione-6-carboxylate (5), rubioncolin C (6), mollugin (7), furomollugin (8), 3-amino-2-methoxycarbonyl-1, 4-naphthoquinone (9), 1-hydroxy-2-methyl-9, 10-anthraquinone (10), 2-hydroxy-6-methyl-9, 10-anthraquinone (11), 1, 4-dihydroxy-2-hydroxymethyl-9, 10-anthraquinone (12), 2-hydroxy-1-methoxy-9, 10-anthraquinone (13), and 1-hydroxy-2-methoxy-6-methyl-9, 10-anthraquinone(14), were isolated from the methanol extract of the roots and rhizomes of Rubia oncotricha using various column chromatographies. Their structures were mainly determined on basis of NMR and MS spectroscopic data analyses. Among them, 1 is a new oleanane triterpene, and compounds 2-5, 9 and 11-13 were obtained from this plant for the first time. Cytotoxic and nematicidal activities of all these compounds were evaluated, and the results showed that only 4, 6, 11 and 12 exhibited cytotoxicities against A549, SGC-7901 and HeLa cancer cell lines. The IC₅₀ of 6 were 19.42, 2.74, 8.07 μmol·L⁻¹, respectively.

Facile preparation and characterization of novel oleanane-type triterpene functionalized β-cyclodextrin conjugates

Oleanolic acid (OA) and echinocystic acid (EA), two naturally occurring pentacyclic oleanane triterpenes, are gaining increasing attention due to their promising pharmacological activities. Conjugation with amphiphilic α(β)-cyclodextrin (CD) via “click chemistry” can improve their solubility and anti-HCV entry potency. In the present work, four water-soluble β-CD-pentacyclic triterpene conjugates were designed and synthesized, in which OA and EA was coupled to one of the primary hydroxyl groups of β-CD via ester and amide bonds. The structures of the conjugates were unambiguously determined by 1H NMR, 13C NMR and HRMS or MALDI-TOF-MS. All the conjugates showed lower hydrophobicity (AlogP) than their parent compounds and no significant cytotoxicity was found to HL-60, A549, Hela and Bel-7402 cells at concentrations up to 10 μmol/L. Further anti-HCV entry activity and mechanism studies are under way in our laboratory.

Two new oleanane derivatives from the fruits of Leonurus japonicus and their cytotoxic activities.

Two new oleanane derivatives, leonuronins A and B (1 and 2), along with three known oleanane triterpenes (3-5) were isolated from the fruits of Leonurus japonicus. Their structures were elucidated on the basis of NMR, MS, IR and UV spectroscopic data. The new compounds were tested for cytotoxic activities against A549 and Hela cancer cell lines. Compounds 1 and 2 exhibited weak cytotoxicity with IC50 values ranging from 6.97 to 18.13μM.

Soyasaponin Ab protects against oxidative stress in HepG2 cells via Nrf2/HO-1/NQO1 signaling pathways

Soyasaponin Ab (SA) is a typical oleanane triterpene saponin isolated from soybean and represents effects of antioxidation and anti-inflammation. In this study, we found the expressions of some phase II detoxifying enzymes were stimulated by SA via the signaling pathway of nuclear factor erythroid 2-related factor 2 (Nrf2) in HepG2 cells. Luciferase assay results demonstrated that SA promoted the Nrf2 transcription via binding to the antioxidant response element. In addition, a combining of luciferase assay and Western blotting suggested that SA activated ERK1/2 signaling pathways, and made Nrf2 translocated from cytoplasm to nucleus. SA also upregulated some Nrf2-related antioxidant enzymes such as heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase-1 (NQO1), and glutamate cysteine ligase catalytic subunit (GCLC). Inhibition of si-Nrf2 resisted expressions of SA-induced antioxidant genes. Collectively, these results suggest that SA exerted its protection against oxidative stress via the Nrf2/HO-1/NQO1 signaling pathways.