HIV latency-reversing activity of latex from Euphorbia umbellata (Pax) Bruyns and three diterpenes isolated from this species.

Two unusual phorbol esters, namely 20-deoxyphorbol-3,4,12-triacetate-13-phenylacetate (1) and phorbol-3,4,12,13-tetraacetate-20-phenylacetate (2) plus ingol-3,8,12-triacetate-7-phenylacetate (3) were isolated from the latex of Euphorbia umbellata and identified by HRESIMS and 2D NMR. Compound 1 is herein described for the first time. Assignment of the phenylacetyl group at C-7 in compound 3 was suggested by the HMBC and NOESY spectra obtained in pyridine-d5. In addition to the latex and its distinct terpenoid fractions, the isolated compounds were tested as latent reversal agents against HIV-1-infected J-Lat cells, with reference to phorbol-12-myristate-13-acetate and ingenol-B. Compound 2 reverted 75-80% the viral latency on the GFP-positive cells, resulting EC50 3.70 µg/mL (SI 6.7), while 1 induced 34-40% reactivation at the same concentration range (4-20 µg/mL). The ingol derivative 3 was ineffective. Phorbol esters were confirmed as effective constituents in the latex since the fraction containing them was 2.4-fold more active than the lyophilised latex at the lowest concentration assayed.

In vitro toxicity of latex, its terpenoidal fractions and isolated phorbol esters from Euphorbia umbellata (Pax) Bruyns on monocytic and melanoma cells.

In Brazil, latex from Euphorbia umbellata (African milk tree) has been increasingly used in folk medicine to treat several types of cancer, including melanoma. The effect of lyophilized latex (LL), its hydroethanolic extract (E80), triterpene (F-TRI)- and diterpene (F-DIT)-enriched fractions, along with six isolated phorbol esters from LL and phorbol 12-myristate 13-acetate (PMA) on J774A.1, THP-1, SK-MEL-28, and B16-F10 cell line viability were evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. The compounds were identified by 2D-NMR and HRESIMS. The effect of the LL, extract and fractions on cell viability was also assessed through a resazurin reduction assay. At 100 µg/ml, LL, and its fractions moderately inhibited J774A.1 (37.5-59.5%) and THP-1 (12.6-43.6%) metabolism. LL (IC50 70 µg/ml) and F-TRI (IC50 68 µg/ml) were barely more effective against B16-F10 cells, and only F-TRI exerted an inhibitory effect on SK-MEL-28 cells (IC50 66-75 µg/ml). The samples did not effectively inhibit THP-1 growth (IC50 69-87 µg/ml, assessed by MTT). B16-F10 was susceptible to PMA (IC50 53 µM) and two 12-phenylacetate esters (IC50 56-60 µM), while SK-MEL-28 growth was inhibited (IC50 58 µM) by one of these kinds of esters with an additional 4ß-deoxy structure. Synagrantol A (IC50 39 µM) was as effective as PMA (IC50 47 µM) in inhibiting J774A.1 growth in a dose-dependent manner. Furthermore, an in silico study with target receptors indicated a high interaction of the compounds with the PKC proteins. These results provide useful knowledge on the effect of tigliane-type diterpenes on tumor cell from the perspective of medicinal chemistry.

Untargeted Metabolomic to Access Chemical Differences Induced by Dual Endophyte Cultures Isolated from Euphorbia Umbellata.

Endophytic fungi live asymptomatically inside vegetal tissues, and such uncommon habitat contributes to their exceptional chemical diversity. Isolating natural products from endophytic fungi could fail due to silent biosynthetic gene clusters under ordinary in vitro culture conditions, and co-culturing has been assayed to trigger their metabolism. We carried out single and dual cultures with 13 endophyte strains isolated from Euphorbia umbellata leaves. Multivariate statistics applied to untargeted metabolomics compared the chemical profiles of all endophyte cultures. PCA analysis guided the selection of the Aspergillus pseudonomiae J1 - Porogramme brasiliensis J9 dual culture for its most significant chemical differentiation: Five compounds were putatively annotated in the J1-J9 culture according to UHPLC-HRMS data, kojic acid, haliclonol and its diastereoisomer, caffeic acid, and 2-(3,4-dihydroxyphenyl)acetaldehyde. Analysis by PLS-DA using VIP score showed that kojic acid displayed the most significative importance in discriminating single and dual J1-J9 cultures.

Bioactive Secondary Plant Metabolites from Euphorbia umbellata (PAX) BRUYNS (Euphorbiaceae).

The species Euphorbia umbellata has been used to treat inflammatory diseases, cancer, and ulcers. Biological activities reported in the literature, including antiproliferative, cytotoxic and anti-inflammatory, are attributed to the chemical constituents present in its composition as terpenes and polyphenolic compounds. The most recurrently verified metabolites in the Euphorbiaceae family plant species are terpenes, of which euphol is a major constituent with broadly reported cytotoxic, antinociceptive and anti-inflammatory effects; it frequently appears in various extracts obtained from the plant. Euphol has a documented inhibitory effect on neutrophil chemotaxis and can modulate the complement system. Since complement system activation is intimately intertwined with autoimmune and inflammatory diseases, tumor growth promotion and metastasis, plant metabolites from Euphorbia umbellata might influence the outcomes of inflammatory processes. We believe that this is the first review presenting the current knowledge on Euphorbia umbellata secondary metabolites and their biological activities.

Toxicological and anti-inflammatory profile of Synadenium grantii Hook. f. in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Synadenium grantii Hook. f., popularly known as "janaúba" or "leiterinha", is used in the folk medicine to treat gastric disorders, some types of neoplasias and inflammatory diseases. AIM OF THE STUDY: The aim of this study was to show the anti-inflammatory activity of the methanol extract obtained from S. grantii stems and also certify the safety of the extract performing toxicological analysis. MATERIAL AND METHODS: The anti-inflammatory activity was investigated using carrageenan-induced inflammation in the subcutaneous tissue of male Swiss mice orally pre-treated with the S. grantii extract (1, 3 or 10 mg/kg). The leukocyte influx (optical microscopy) and secretion of chemical mediators (TNF, IL-6 and IL-1ß, by enzyme-linked immunosorbent assay) were quantified in the inflamed exudate. The toxicity was investigated using the dose-fixed procedure (acute toxicity) and repeated dose 28-day (subacute toxicity) in mice orally treated with S. grantii extract. The open field and rota-rod test were used to evaluate possible interference of adverse effect of S. grantii on motor coordination, locomotor and exploratory activity. RESULTS: The analysis of the inflammatory exudate of S. grantii-treated mice demonstrated reduction in the polymorphonuclear cells (PMN) migration to the inflamed tissue, as well as the reduction of the pro-inflammatory cytokines TNF and IL-1ß. Furthermore, the acute and sub-acute toxicity studies did not show significant changes in body weight, general behaviour, biochemical parameters, organ weight and liver and kidney histopathological analysis. However, animals acutely treated with S. grantii presented reduction in the number of crosses in relation to the vehicle group, without significant difference in the number of elevations and latency time between the groups in rota-rod test. The obtained results allow to set the NOAEL (Non-observed-adverse-effect level) in 100 mg/kg for this specie of rodent. CONCLUSIONS: Together, the results herein obtained show that S. grantii extract presented anti-inflammatory activity by decreasing the influx of PMN to the inflamed tissue, as well as the cytokines TNF and IL-1ß levels. In addition, S. grantii extract seemed not to present significant acute or subacute toxicity when administered to mice, demonstrating for the first time the safety of this extract, when orally administered.

Effect of Synadenium grantii and its isolated compound on dysmenorrhea behavior model in mice.

OBJECTIVE: This study aimed to evaluate the effects of the methanol extract of Synadenium grantii Hook f. stems and its main isolated compound Query3,4,12,13-tetraacetylforbol-20-phenylacetate (1) on experimental dysmenorrhea in mice. METHODS: Female Swiss mice (n = 6-15) of 6-8 weeks old were used, selected according to the period of the estrous cycle. Animals in proestrus were treated intraperitoneally (i.p.) for 3 days with estradiol. They orally received, on the 4th day, S. grantii extract, the compound 1, ibuprofen or hyoscine butylbromide (Buscopan compound®). Then they were injected (i.p.) with oxytocin 1 h later and individually observed regarding the abdominal writhing for 45 min. The uterus was weighed, photographed and fixed in paraffin for histological analysis. KEY FINDINGS: The extract inhibited the abdominal writhing and similar results were obtained with compound 1 and the positive control drugs Ibuprofen and hyoscine butylbromide. Reduction of uterus volume and histological inflammatory parameters, such as oedema and leukocyte infiltrate, were observed in animals treated with the extract and compound 1. CONCLUSIONS: Our data show promising activity of the extract against dysmenorrhea, indicating important anti-inflammatory activity. Compound 1 appears to be, at least in part, the main responsible for this promising biological effect.

Cytotoxic biomonitored study of Euphorbia umbellata (Pax) Bruyns.

ETHNOPHARMACOLOGICAL RELEVANCE: Euphorbia umbellata latex (sap) has normally been used in folk medicine in southern Brazil to treat different types of cancers. AIM OF STUDY: To carry out a biomonitored investigation of partitioned latex using in vitro assay, to identify the main mechanisms related with the action of the most active fraction as well as to develop a phytochemical study with this material. MATERIALS AND METHODS: Biological screening was performed with hexane, chloroform, ethyl acetate and methanol fractions from the latex of E. umbellata using MTT, trypan blue, and neutral red assays to determine the cytotoxicity against HRT-18, HeLa and Jurkat cells and flow cytometry, DNA quantification, acridine orange and Hoechst 33342 staining to investigate mechanisms of action for the hexane extract. The phytochemical study of the hexane fraction was performed by chromatographic procedures and the substances were identified by NMR analysis. The isolated terpenes were evaluated using MTT to determine the cytotoxicity against Jurkat cells. RESULTS: All the fractions presented concentration and time dependent cytotoxicity. The hexane fraction showed the highest cytotoxicity; whereas the Jurkat cell was the lineage with the highest sensitivity (IC50 1.87µg/mL). Fragmentation of DNA and apoptosis are two mechanisms related with the toxicity of hexane fraction. The hexane fraction arrested the cell cycle in the G0/G1 phase, and the selectivity index was 4.30. Phytochemical study of the hexane fraction led to isolation of euphol (main compound) and germanicol acetate. Both substances demonstrated some slight cytotoxic activity against Jurkat cells after 72h; however the activity was minimal compared to vincristine (anticancer standard drug). CONCLUSION: The current research proves that the fractions of the latex from E. umbellata have a cytotoxic effect against three different cancer cells lines. The hexane fraction showed high in vitro cytotoxic effects against Jurkat cells demonstrating that the effect may be due to non-polar constituents. The two isolated terpenes (euphol and germanicol acetate) showed poor cytotoxic activity indicating that the anticancer properties of the extract may be caused by other substances present in the hexane fraction.