Ursolic Acid Lactone Research Articles

Robustanic acid as a glutaminase and Na+, K+-ATPase inhibitor from leaves of Eucalyptus globulus.

This study was to compare glutaminase and Na+, K+-ATPase inhibitory activities of 20 herbal extracts and investigate the isolation, structural elucidation and those inhibitory activities of three triterpenes from the selected extract of Eucalyptus globulus Labill. Three triterpenes, ursolic acid (1), robustanic acid (2) and ursolic acid lactone (3), were identified by analyzing their NMR and MS spectral data and comparison of these with reported data. The IC50 values of 1-3 and the control compound against glutaminase, 6-diazo-5-oxo-l-norleucine (DON), were 443 μM, 334 μM, 963 μM and 134 μM, respectively. The IC50 values of 1, 2 and the control compound against Na+, K+-ATPase and ouabain, were 180 μM, 56 μM and 0.5 μM, respectively. Compounds 1 and 2 may serve as potential lead compounds for the prevention and treatment of neurodegenerative and lifestyle-related diseases by targeting glutaminase and Na+, K+-ATPase. This is the first report on glutaminase and Na+, K+-ATPase inhibitory activities of 2.

RNA-seq analysis reveals modulation of inflammatory pathways by an enriched-triterpene natural extract in mouse and human macrophage cell lines

Chronic inflammation is crucial in developing insulin resistance and type 2 diabetes. Previous studies have shown that a leaf extract of Eucalyptus tereticornis, with ursolic acid (UA), oleanolic acid (OA), and ursolic acid lactone (UAL) as the main molecules (78 %) mixed with unknown minor metabolites (22 %), provided superior anti-inflammatory, hypoglycemic, and hypolipidemic effects than reconstituted triterpenoid mixtures in macrophage cell lines and a pre-diabetic mouse model. Further identification of the molecular mechanisms of action of this mixture of triterpenes is required. This study aims to analyse the RNA expression profiles of mouse and human macrophage cell lines treated with the natural extract and its components. Activated macrophage cell lines were treated with the natural extract, UA, OA, UAL or a triterpene mixture (M1). RNA was extracted and sequenced using the DNBseq platform and the EnrichR software to perform gene enrichment analysis using the Gene Ontology database, Kyoto Encyclopedia of Genes and Genomes, and Reactome. To conduct clustering analysis, we standardised the normalised counts of each gene and applied k-means clustering. The combination of molecules in the natural extract has an additive or synergic effect that affects the expression of up-regulated genes by macrophage activation. Triterpenes (M1) regulated 76 % of human and 68 % of mouse genes, while uncharacterised minority molecules could regulate 24 % of human and 32 % of mouse genes. The extract inhibited the expression of many cytokines (IL6, IL1, OSM), chemokines (CXCL3), inflammatory mediators (MMP8 and MMP13) and the JAK-STAT signalling pathway in both models. The natural extract has a more powerful immunomodulatory effect than the triterpene mixture, increasing the number of genes regulated in mouse and human models. Our study shows that Eucalyptus tereticornis extract is a promising option for breaking the link between inflammation and insulin resistance.

An integrated transcriptomic and metabolomic analysis for changes in rose plant induced by rose powdery mildew and exogenous salicylic acid

We explored the transcriptomic and metabolomic changes in Rosa chinensis after the infection with Podosphaera pannosa and after the treatment with exogenous salicylic acid (SA), separately. The rose responses to the mildew-infection were clearly similar to the responses to the SA-treatment. Based on the combined omics analysis, after the induction by both P. pannosa and SA, R. chinensis responded consistently by MAPK cascades, plant-pathogen interaction pathway activation, and resistance (R) genes expression, and further, triterpenoid biosynthesis, glutathione metabolism, and linoleic acid metabolism were significantly enriched when compared with the control. The levels of the triterpenoids with the largest fold change values were significantly up-regulated such as dehydro (11,12) ursolic acid lactone and maslinic acid, suggesting that these pathways and metabolites were involved in the resistance to P. pannosa. The contents of salicylic acid beta-D-glucoside, methyl salicylate, and methyl jasmonate increased significantly resulting from both P. pannosa-infection and exogenous SA-treatment.

Ursolic Acid Lactone Obtained from Eucalyptus tereticornis Increases Glucose Uptake and Reduces Inflammatory Activity and Intracellular Neutral Fat: An In Vitro Study.

Obesity has a strong relationship to insulin resistance and diabetes mellitus, a chronic metabolic disease that alters many physiological functions. Naturally derived drugs have aroused great interest in treating obesity, and triterpenoids are natural compounds with multiple biological activities and antidiabetic mechanisms. Here, we evaluated the bioactivity of ursolic acid lactone (UAL), a lesser-known triterpenoid, obtained from Eucalyptus tereticornis. We used different cell lines to show for the first time that this molecule exhibits anti-inflammatory properties in a macrophage model, increases glucose uptake in insulin-resistant muscle cells, and reduces triglyceride content in hepatocytes and adipocytes. In 3T3-L1 adipocytes, UAL inhibited the expression of genes involved in adipogenesis and lipogenesis, enhanced the expression of genes involved in fat oxidation, and increased AMP-activated protein kinase phosphorylation. The range of biological activities demonstrated in vitro indicates that UAL is a promising molecule for fighting diabetes.

Major triterpenoids from Eucalyptus tereticornis have enhanced beneficial effects in cellular models when mixed with minor compounds present in raw extract.

Obesity is a major risk factor for type 2 diabetes mellitus development and is characterized by an abnormal expansion of adipose tissue and low-grade chronic inflammation that contribute to insulin resistance. Although there are multiple treatments, most therapies can produce undesirable side effects and therefore, new and effective treatments with fewer side effects are necessary. Previously, we demonstrated that a natural extract from the leaves of Eucalyptus tereticornis (OBE100) has anti-inflammatory, hypoglycemic and hypolipidemic activities. The major compounds identified in OBE100 were three pentacyclic triterpenoids, ursolic acid, oleanolic acid, and ursolic acid lactone. Triterpenoids have shown multiples biological activities. This current study compared the biological effect produced by OBE100 with five different reconstituted mixtures of these triterpenoids. Different cell lines were used to evaluate cytotoxicity, reactive oxygen species production, inflammatory cytokine expression, glucose uptake induction, leptin and adiponectin expression, and lipid accumulation. OBE100 treatment was the most efficacious and none of the formulated triterpenoid mixtures significantly improved on this. Moreover, OBE100 was less toxic and reduced reactive oxygen species production. Our study showed that the proven beneficial properties of triterpenoids may be enhanced due to the interaction with minor secondary metabolites present in the natural extract improving their anti-inflammatory properties.

Triterpene-enriched fractions from Eucalyptus tereticornis ameliorate metabolic alterations in a mouse model of diet-induced obesity

Etnopharmacological relevanceEucalyptus tereticornis Sm. (Eu) is a plant species used in traditional medicine to treat diabetes mellitus. Eu leaf extracts have been shown to regulate immuno-metabolic activities that are associated with obesity and insulin resistance. OBE100 and OBE104 are two natural Eu extracts that are rich in pentacyclic triterpenes. The major compounds identified in OBE100 are ursolic acid (UA), oleanolic acid (OA), and ursolic acid lactone (UAL), and the major compounds identified in OBE104 are UA and OA. Aim of the studyThis study aimed to investigate the effects of two extracts from Eu leaves with different triterpene composition in a nutritional animal model of prediabetes. MethodsA mouse model of diet-induced obesity was used to analyze the effects of the OBE100 and OBE104 treatments on metabolic markers and gene expression in liver and visceral adipose tissue. ResultsTreating the prediabetic mouse model with OBE100 and OBE104 increased glucose tolerance. However, only the Eu extract that contained three triterpenes reduced mouse body weight, hepatic and adipose fat content, and plasma lipid levels. OBE100 treatment also led to decreased hepatic mRNA levels of PPARA, CPT1A, and SERBP1. In visceral adipose tissue, OBE100 treatment reduced expression of PPARA and ACACA and increased UCP1 expression. ConclusionsThese results suggest that developing a new multitargeting bioactive compound from the natural extract from Eu may help combat obesity and diabetes. Treatment with OBE100 had better effects than OBE104 in a diet-induced obesity mouse model, suggesting that the OBE100 extract, which contains three triterpenes, may be beneficial in combating obesity.

LC-ESI-MS/MS profiling of alkaloids and antiproliferative activity of Pachypoduim lamerei drake leaves

In the present study, evaluation of the antiproliferative activity of Pachypodium lamerei Drake leaves (family Apocyaceae) against human breast cancer cell lines MDA-MB-231 was done for the total methanolic extract, crude alkaloidal mixture and ursolic acid using the MTT colorimetric assay. The methanolic extract showed the strongest antiproliferative activity followed by ursolic acid and crude alkaloidal fraction with an IC50 equal to 6.2, 14.55 and 56.3 µg/ml respectively compared to oleocanthal. It is the first record for the LC/ESI-MS/MS alkaloidal profiling of the leaves of P. lamerei. Seven alkaloids were tentatively identified according to their fragmentation patterns. Four alkaloids were related to the parent indole class and two alkaloids belong to the quinoline class in addition to one steroidal alkaloid with a pregnan nucleus. Phytochemical investigation of the methanolic extract led to the isolation of three triterpenoidal compounds including ursolic acid, 11,12-didehydroursolic acid lactone and ursolic acid lactone.

Immunometabolic regulation by triterpenes of Eucalyptus tereticornis in adipose tissue cell line models

Eucalyptus tereticornis Sm (Myrtaceae) is a plant used in traditional medicine to control obesity, insulin resistance and diabetes. Chronic adipose tissue inflammation is involved in generating insulin resistance, the greatest risk factor in developing type 2 diabetes mellitus and cardiovascular disease. In the present study, a mixture of triterpenes, as obtained from the starting plant material, was evaluated in inflamed adipose tissue cells models. Our goal is to advance into the understanding, at the cellular level, of the immunometabolic effects of the triterpene mixes from Eucalyptus tereticornis in in vitro models of mouse and human adipose tissues. Triterpene mixes were obtained from Eucalyptus tereticornis leaves by organic extraction. The major compounds of these mixes were identified by 1H NMR and 13C NMR in addition to HPLC using primary and secondary standards of ursolic acid, oleanolic acid and ursolic acid lactone. To provide an approach for evaluating the cellular and molecular mechanisms through which triterpene mixes act to modify the metabolic processes associated with obesity, mouse macrophage and adipocyte cell lines, human macrophage cell line and primary culture of human adipocytes were used as models. Adipocytes treated with the two natural chemically characterized triterpene mixes partially reduce lipogenesis and leptin expression. Additionally, an increase in the transcriptional expression of PPARγ, and C/EBPα is observed. In macrophages, these triterpene mixes, decrease the transcriptional and translational expression of pro-inflammatory cytokines, such as interleukin-6 (IL-6), interleukin 1β (IL-1β) and tumoral necrosis factor α (TNFα). Conditioned medium of 3T3-L1 adipocytes treated with the triterpene mix shows a stronger anti-inflammatory response on activated J774A.1 macrophages. The mixtures of the three triterpenes in the proportions obtained from the plant material may act on different components of the cell, generating a different response, which, in some cases, is more powerful than that seen when exposure to only two triterpenes. It makes this three triterpenes mix a good phytotherapeutic prototype for pathologies as complex as those associated with obesity.

Ursocholanic acid rescues mitochondrial function in common forms of familial Parkinson’s disease

Previous drug screens aiming to identify disease-modifying compounds for Parkinson's disease have typically been based on toxin-induced in vitro and in vivo models of this neurodegenerative condition. All these compounds have failed to have a reliable disease-modifying effect in subsequent clinical trials. We have now established a novel approach, namely to screen an entire compound library directly in patient tissue to identify compounds with a rescue effect on mitochondrial dysfunction as a crucial pathogenic mechanism in Parkinson's disease. The chosen Microsource Compound library contains 2000 compounds, including 1040 licensed drugs and 580 naturally occurring compounds. All 2000 compounds were tested in a step-wise approach for their rescue effect on mitochondrial dysfunction in parkin (PARK2) mutant fibroblasts. Of 2000 compounds, 60 improved the mitochondrial membrane potential by at least two standard deviations. Subsequently, these 60 compounds were assessed for their toxicity and drug-like dose-response. The remaining 49 compounds were tested in a secondary screen for their rescue effect on intracellular ATP levels. Of 49 compounds, 29 normalized ATP levels and displayed drug-like dose response curves. The mitochondrial rescue effect was confirmed for 15 of these 29 compounds in parkin-mutant fibroblasts from additional patients not included in the initial screen. Of 15 compounds, two were chosen for subsequent functional studies, namely ursocholanic acid and the related compound dehydro(11,12)ursolic acid lactone. Both compounds markedly increased the activity of all four complexes of the mitochondrial respiratory chain. The naturally occurring compound ursolic acid and the licensed drug ursodeoxycholic acid are chemically closely related to ursocholanic acid and dehydro(11,12)ursolic acid lactone. All four substances rescue mitochondrial function to a similar extent in parkin-mutant fibroblasts, suggesting a class effect. The mitochondrial rescue effect depends on activation of the glucocorticoid receptor with increased phosphorylation of Akt and was confirmed for both ursocholanic acid and ursodeoxycholic acid in a Parkin-deficient neuronal model system. Of note, both ursocholanic acid and ursodeoxycholic acid also rescued mitochondrial function in LRRK2(G2019S) mutant fibroblasts. Our study demonstrates the feasibility of undertaking drug screens in Parkinson's disease patients' tissue and has identified a group of chemically-related compounds with marked mitochondrial rescue effect. Drug repositioning is considered to be a time- and cost-saving strategy to assess drugs already licensed for a different condition for their neuroprotective effect. We therefore propose both ursolic acid as a naturally occurring compound, and ursodeoxycholic acid as an already licensed drug as promising compounds for future neuroprotective trials in Parkinson's disease.

In Vitro Antiprotozoal Activity of Triterpenoid Constituents of Kleinia odora Growing in Saudi Arabia

Two lupane and four ursane triterpenes, namely epilupeol (1), lupeol acetate (2), ursolic acid (3), brein (4), 3β 11α-dihydroxy urs-12-ene (5) and ursolic acid lactone (6) were isolated from aerial parts of Kleinia odora and identified. Compounds 1 and 3–6 were isolated for the first time from K. odora. The triterpene constituents were investigated for antiprotozoal potential against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. Cytotoxicity was determined against MRC-5 fibroblasts to assess selectivity. The ursane triterpenes were found to be active against more than one type of the tested parasites, with the exception of compound 6. This is also the first report on the occurrence of ursane type triterpenes in the genus Kleinia and their antiprotozoal potential against P. falciparum, L. infantum, T. cruzi, and T. brucei.

Determination of ursolic acid and ursolic acid lactone in the leaves of Eucalyptus tereticornis by HPLC

A simple isocratic HPLC method has been developed for the simultaneous quantification of two bioactive triterpenes, ursolic acid and ursolic acid lactone in E. tereticornis leaves. Samples were analyzed on RP-18 (4.6 × 250 mm, 5 µm) column with methanol and water acidified to pH 3.5 with TFA (88:12) at 210 nm. The method was validated and applied for the simultaneous quantification of the individual triterpenes in E. tereticornis extract. The calibration curves were linear over a concentration range of 0.05-0.3 mg mL -1 (r = 0.999 and 0.998, respectively). The limits of detection and quantification were 0.190 and 0.644 µg for ursolic acid, and 0.176 and 0.587 µg for ursolic acid lactone, while the percentage recoveries were 97.32 and 96.23% for ursolic acid and ursolic acid lactone, respectively. This is the first report on the HPLC method of ursolic acid lactone with high precision and accuracy.

Preparative-Scale Separation of Anticancer Triterpenes from Eucalyptus hybrid by Centrifugal Partition Chromatography

Centrifugal partition chromatography was successfully applied in the separation of close R f complex anticancer triterpenes directly from a fraction of Eucalyptus hybrid (Myrtaceae). The experiment was performed with a two-phase solvent system composed of hexane/ethyl acetate/methanol/water (1:2:1.5:1 v/v/v) where 2% ammonia solution was added in lower aqueous mobile phase to achieve pH 9.5. From 1.5 g of a fraction, 145 mg of ursolic acid and 72 mg of ursolic acid lactone were obtained in 95.4% and 94.8% purities. The total yield recovery was >94% and the isolated triterpenes were characterized on the basis of their 1H, 13C-NMR, and ESI-MS data.

Chromenone Glucosides Acylated with Monoterpene Acids from the Leaves of Eucalyptus camaldulensis var. obtusa

AbstractThree new chromenone glucosides acylated with monoterpene acids, eucamaldusides A (1), B (2), and C (3), were isolated from the leaves of Eucalyptus camaldulensis var. obtusa, together with the five known compounds ursolic acid lactone, obtusilin, β‐sitosterol glucoside, 4‐hydroxybenzoic acid, and cypellocarpin C. The structures of the new compounds were established by exhaustive 1D‐ and 2D‐NMR spectroscopic studies. Their configuration was determined by measuring the [α]D of the known methyl esters of the monoterpene acids obtained by methanolysis of 1–3.

Constituents of Baccharis dracunculifolia DC (Asteraceae) with in vitro antileishmanial, antiplasmodial and cytotoxic activities

Baccharis dracunculifolia D.C. (Asteraceae) is the most important plant source of the Brazilian green propolis. The aim of this work was to evaluate the antileishmanial and antiplasmodial activities of B. dracunculifolia and its isolated compounds. The leave rinse extract of B. dracunculifolia (BdE) showed in vitro antileishmanial activity against Leishmania donovani, displaying an IC50 value of 45µg/mL, while green propolis hydroalcoholic extract (GPE) showed an IC50 value of 49µg/mL. Among the isolated compounds, ursolic acid and hautriwaic acid lactone, showed the highest antileishmanial activities, displaying IC50 values of 3.7µg/mL and 7.0µg/mL, respectively. The pentacyclic triterpene Uvaol, as well as the flavonoids acacetin and ermanin showed IC50 values of 15.0µg/mL, 18.0µg/mL and 40.0µg/mL, respectively. Regarding the antiplasmodial assay against Plasmodium falciparum, BdE and GPE showed similar IC50 values (about 20µg/mL). Hautriwaic acid lactone displayed moderate antiplasmodial activity, with IC50 values of 0.8µg/mL (D6 clone) and 2.2µg/mL (W2 clone). In order to compare the effect on the parasites with toxicity with mammalian cells, the cytotoxic activity of the samples were evaluated against the Vero cells, showing that all evaluated compounds exhibited no cytotoxicity in the maximum dose tested.

In vitro antileishmanial, antiplasmodial and cytotoxic activities of phenolics and triterpenoids from Baccharis dracunculifolia D. C. (Asteraceae)

Baccharis dracunculifolia (Asteraceae), the most important plant source of the Brazilian green propolis (GPE), displayed in vitro activity against Leishmania donovani, with an IC(50) value of 45 microg/mL, while GPE presented an IC(50) value of 49 microg/mL. Among the isolated compounds of B. dracunculifolia, ursolic acid, and hautriwaic acid lactone showed IC(50) values of 3.7 microg/mL and 7.0 microg/mL, respectively. Uvaol, acacetin, and ermanin displayed moderate antileishmanial activity. Regarding the antiplasmodial assay against Plasmodium falciparum, BdE and GPE gave similar IC(50) values (about 20 microg/mL), while Hautriwaic acid lactone led to an IC(50) value of 0.8 microg/mL (D6 clone).

Chemical composition of the epicuticular wax from the fruits ofEucalyptus globulus

The chemical composition of the epicuticular wax from the fruits of Eucalyptus globulus was studied by GC-MS before and after alkaline hydrolysis. The wax had two main components, ursolic acid and tritriacontan-16,18-dione, together with several other triterpenic acids. After alkaline hydrolysis, a large increase in the amounts of triterpenic acids and fatty acids (particularly in hexadecanoic acid) was observed, suggesting that these components were present predominantly in esterified forms in the fruit wax. Six compounds were isolated from the fruits by preparative chromatography, and were identified as 8-desmethyleucalyptin, sesamin, tritriacontan-16,18-dione, ursolic acid, 3beta-hydroxyurs-11-en-13beta(28)-olide (ursolic acid lactone) and 3beta,11alpha-dihydroxyurs-12-en-28-oic acid, the latter of which was identified for the first time.

Antiproliferative Constituents from Umbelliferae Plants VII. Active Triterpenes and Rosmarinic Acid from Centella asiatica

The antiproliferative constituents in the MeOH extract from the aerial parts of Centella asiatica were investigated. Activity-guided fractionation of MeOH extract resulted in the isolation of ursolic acid lactone, ursolic acid, pomolic acid, 2alpha,3alpha-dihydroxyurs-12-en-28-oic acid, 3-epimaslinic acid, asiatic acid, corosolic acid, and rosmarinic acid. Antiproliferative activity of the isolated compounds against human gastric adenocarcinoma (MK-1), human uterine carcinoma (HeLa), and murine melanoma (B16F10) cells was estimated.

Triterpenoidal constituents from Eucalyptus camaldulensis var. obtusa leaves

An investigation on the constituents of the fresh, uncrushed leaves of Eucalyptus camaldulensis var. obtusa has led to the isolation of the triterpenoid amirinic acid and four known triterpenoids ursolic acid lactone, betulinic acid, oleanolic acid and ursolic acid. Amirinic acid transformed into amirolide in deuterated chloroform at room temperature. The new products were characterized by exhaustive spectroscopic studies as 2α,3β,7β-trihydroxy-11α-methoxyurs-12-en-28-oic acid and 2α,3β,7β-trihydroxyurs-11-en-28,13β-olide.

Spasmolytic constituents from Eucalyptus camaldulensis var. obtusa leaves.

Phytochemical studies on the leaves of Eucalyptus camaldulensis var. obtusa have resulted in the isolation of a new triterpenoid camaldulin (3beta-formyloxyurs-11-en-28,13beta-olide) (1) along with ursolic acid lactone acetate (2), ursolic acid lactone (3), betulinic acid (4), and beta-sitosterol 3-O-beta-D-glucopyranoside (5). The structures were assigned on the basis of 1D and 2D NMR studies. Compounds 1-3 were tested for spasmolytic activity and were found to possess calcium antagonist activity.

Isolation and Structural Elucidation of Acylated Pentacyclic Triterpenoids from the Leaves ofEucalyptus camaldulensisvar.obtusa

Ten pentacyclic triterpenoids including two new constituents, eucalyptic acid and eucalyptolic acid, and eight known compounds (ursolic acid lactone, betulinic acid, oleanolic acid, ursolic acid, 3β-O-cis-p-coumaroylalphitolic acid, alphitolic acid, 3β-O-trans-p-coumaroylalphitolic acid, and 3β-O-trans-p-coumaroylmaslinic acid) have been isolated from the fresh and uncrushed leaves of Eucalyptus camaldulensis var. obtusa. Their structures were elucidated through detailed 1D and 2D NMR studies. The new natural products were characterized as 2α-hydroxy-3β-E-feruloyloxy-lup-20(29)-en-28-oic acid and 2α-hydroxy-3β-E-feruloyloxy-olean-12-en-28-oic acid, respectively. Except for oleanolic acid, all the known compounds are hitherto unreported from this plant. This is the first report of the isolation of 2-oxygenated 3-O-acylated triterpenoids from Eucalyptus genus.