Quassinoids from Twigs of Harrisonia perforata (Blanco) Merr and Their Anti-Parkinson's Disease Effect.

Six new C-20 and one new C-19 quassinoids, named perforalactones F-L (1-7), were isolated from twigs of Harrisonia perforata. Spectroscopic and X-ray crystallographic experiments were conducted to identify their structures. Through oxidative degradation of perforalactone B to perforaqussin A, the biogenetic process from C-25 quassinoid to C-20 via Baeyer-Villiger oxidation was proposed. Furthermore, the study evaluated the anti-Parkinson's disease potential of these C-20 quassinoids for the first time on 6-OHDA-induced PC12 cells and a Drosophila Parkinson's disease model of PINK1B9. Perforalactones G and I (2 and 4) showed a 10-15% increase in cell viability of the model cells at 50 µM, while compounds 2 and 4 (100 µM) significantly improved the climbing ability of PINK1B9 flies and increased the dopamine level in the brains and ATP content in the thoraces of the flies.

Cytotoxicity of the methanol extracts and compounds of Brucea antidysenterica (Simaroubaceae) towards multifactorial drug-resistant human cancer cell lines.

BACKGROUND: Cancer remains a global health concern and constitutes an important barrier to increasing life expectancy. Malignant cells rapidly develop drug resistance leading to many clinical therapeutic failures. The importance of medicinal plants as an alternative to classical drug discovery to fight cancer is well known. Brucea antidysenterica is an African medicinal plant traditionally used to treat cancer, dysentery, malaria, diarrhea, stomach aches, helminthic infections, fever, and asthma. The present work was designed to identify the cytotoxic constituents of Brucea antidysenterica on a broad range of cancer cell lines and to demonstrate the mode of induction of apoptosis of the most active samples. METHODS: Seven phytochemicals were isolated from the leaves (BAL) and stem (BAS) extract of Brucea antidysenterica by column chromatography and structurally elucidated using spectroscopic techniques. The antiproliferative effects of the crude extracts and compounds against 9 human cancer cell lines were evaluated by the resazurin reduction assay (RRA). The activity in cell lines was assessed by the Caspase-Glo assay. The cell cycle distribution, apoptosis via propidium iodide (PI) staining, mitochondrial membrane potential (MMP) through 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining, and the reactive oxygen species (ROS) via 2´,7´-dichlorodihydrofluoresceine diacetate (H2DCFH-DA) staining, were investigated by flow cytometry. RESULTS: Phytochemical studies of the botanicals (BAL and BAS) led to the isolation of seven compounds. BAL and its constituents 3, (3-(3-Methyl-1-oxo-2-butenyl))1H indole (1) and hydnocarpin (2), as well as the reference compound, doxorubicin, had antiproliferative activity against 9 cancer cell lines. The IC50 values varied from 17.42 µg/mL (against CCRF-CEM leukemia cells) to 38.70 µg/mL (against HCT116 p53-/- colon adenocarcinoma cells) for BAL, from 19.11 µM (against CCRF-CEM cells) to 47.50 µM (against MDA-MB-231-BCRP adenocarcinoma cells) for compound 1, and from 4.07 µM (against MDA-MB-231-pcDNA cells) to 11.44 µM (against HCT116 p53+/+ cells) for compound 2. Interestingly, hypersensitivity of resistant cancer cells to compound 2 was also observed. BAL and hydnocarpin induced apoptosis in CCRF-CEM cells mediated by caspase activation, the alteration of MMP, and increased ROS levels. CONCLUSION: BAL and its constituents, mostly compound 2, are potential antiproliferative products from Brucea antidysenterica. Other studies will be necessary in the perspective of the discovery of new antiproliferative agents to fight against resistance to anticancer drugs.

Antiplasmodial and cytotoxic effects of the methanol extract, canthinone alkaloids, squalene- and protolimonoid-type triterpenes from Homalolepis suffruticosa roots.

ETHNOPHARMACOLOGICAL RELEVANCE: Different species of the Simaroubaceae family are used in traditional medicine to treat malaria. Among these is Homalolepis suffruticosa (syn. Simaba suffruticosa and Quassia suffruticosa), which is native to Central Brazil and popularly known as calunga. However, there is a lack of investigation concerning its antimalarial effects. AIM OF THE STUDY: To investigate the antiplasmodial and cytotoxic effects of the isolated metabolites and methanol extract from H. suffruticosa roots as well as to conduct the dereplication of this extract aiming to characterize its metabolic profile by UPLC-DAD-ESI-MS/MS. MATERIALS AND METHODS: Methanol extract of the H. suffruticosa roots and six isolated compounds were evaluated against chloroquine-resistant Plasmodium falciparum W2 strain by the PfLDH method and cytotoxicity in HepG2 cells by the MTT assay. Dereplication of the extract was performed by UPLC-DAD-ESI-MS/MS. RESULTS: The six isolated compounds disclosed high to moderate antiplasmodial activity (IC50 0.0548 ± 0.0083 µg/mL to 26.65 ± 2.40 µg/mL) and cytotoxicity was in the range of CC50 0.62 ± 0.33 µg/mL to 56.43 ± 2.54 µg/mL, while 5-metoxycantin-6-one proved to be the most potent constituent of the six assayed ones. The methanol extract of the roots showed high in vitro antiplasmodial activity (IC50 1.88 ± 0.56 µg/mL), moderate cytotoxicity (CC50 41.93 ± 2.30 µg/mL), and good selectivity index (SI = 22.30). Finally, C20 quassinoids and canthin-6-one alkaloids were putatively identified in the H. suffruticosa methanol extract by LC-MS. CONCLUSIONS: Taken together, the isolated compounds, mainly the 5-metoxycantin-6-one and the methanol extract from H. suffruticosa roots, disclose good antiplasmodial activity, supporting the ethnopharmacological history of the Simaroubaceae species as traditional antimalarial drugs.

[An integrative metabolomics and network pharmacology method for exploring bioactive components and preliminary pharmacodynamics in medicinal parts of Harrisonia perforata].

In this paper,metabolomics and network pharmacology were used to investigate the bioactive components of Harrisonia perforata and their possible mechanisms of action. Metabolites in the flowers,fruits,branches,leaves and stalks of H. perforata were analyzed by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Meanwhile,multiple statistical analysis methods including principal component analysis( PCA) and orthogonal partial least squares discriminant analysis( OPLS-DA)were applied to screen and identify differential compounds. With metabolomics method,9 differential compounds were preliminarily identified from leaves and other non-traditional medicinal parts. Subsequently,these compounds were explored by using network pharmacology. With gastrointestinal absorption and drug-likeness as limiting conditions,they were imported into the Swiss ADME,from which 7 compounds with potential medicinal activity were obtained. Then,their targets were predicted by PharmMapper,with Human Protein Targets Only and Normalized Fit Score>0. 9 set as limiting conditions,and 60 standardized potential targets were identified with Uniprot. KEGG( Kyoto encyclopedia of genes and genomes) pathway data was obtained using metascape and the " potential active ingredients-target-pathway" network was constructed with Cytoscape 3. 7. 2. The enrichment analysis of KEGG demonstrated that the 60 targets were enriched in 78 signaling pathways( min overlap: 3,P value cutoff: 0. 01,min enrichment: 1. 5),many of which are related to anti-bacteria,anti-inflammation and anti-virus,such as IL-17 signaling pathway,RIG-I-like receptor signaling pathway and NOD-like receptor signaling pathway. Finally,depending on the clinical activity of H. perforata,the relevant signaling pathways were analyzed through experimental data and literature. Dehydroconiferyl alcohol was reported to have the anti-inflammatory effect and perforamone D to possess the antimycobacterial activity. The KEGG pathway enrichment analysis showed that dehydroconiferyl alcohol could act on the Alzheimer's disease( AD) signaling pathway by targeting CDK5 R1 and BACE1. ACh E inhibitor is the most promising drug to treat AD,while dehydroconiferyl alcohol has been proved to inhibit ACh E according to literature. The experimental results revealed that the extract of leaves of H. perforata can effectively inhibit the growth of Staphylococcus aureus. These are consistent with the enrichment analysis results of KEGG. This study explored the bioactive components and pharmacodynamics of the leaves of the H. perforata,laying a theoretical foundation for its in-depth development and rational application.

Quassinoids: Phytochemistry and antitumor prospect.

Quassinoids, originating from the oxidative degradation of tetracyclic tirucallane triterpene, are a diverse class of secondary metabolites identifying from nature mostly in Simaroubaceae family. The crucial pharmacological activities and structural complexity of quassinoids have long fascinated scientists due to their medicinal uses, infamous toxicity, and unique biosynthesis. In the past few decades, 482 quassinoids, assigned to 6 skeletons, have been isolated and identified from plants. The names, classes, molecular formula, and plant sources of these secondary metabolites are collated here. This review will be a detailed update of the naturally occurring quassinoids reported from the plant kingdom, providing an in-depth discussion of their diversity, antitumor activities, structure-activity relationship.

An integrative metabolomics and network pharmacology method for exploring bioactive components and preliminary pharmacodynamics in medicinal parts of Harrisonia perforata / 中国中药杂志

In this paper,metabolomics and network pharmacology were used to investigate the bioactive components of Harrisonia perforata and their possible mechanisms of action. Metabolites in the flowers,fruits,branches,leaves and stalks of H. perforata were analyzed by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Meanwhile,multiple statistical analysis methods including principal component analysis( PCA) and orthogonal partial least squares discriminant analysis( OPLS-DA)were applied to screen and identify differential compounds. With metabolomics method,9 differential compounds were preliminarily identified from leaves and other non-traditional medicinal parts. Subsequently,these compounds were explored by using network pharmacology. With gastrointestinal absorption and drug-likeness as limiting conditions,they were imported into the Swiss ADME,from which 7 compounds with potential medicinal activity were obtained. Then,their targets were predicted by PharmMapper,with Human Protein Targets Only and Normalized Fit Score>0. 9 set as limiting conditions,and 60 standardized potential targets were identified with Uniprot. KEGG( Kyoto encyclopedia of genes and genomes) pathway data was obtained using metascape and the " potential active ingredients-target-pathway" network was constructed with Cytoscape 3. 7. 2. The enrichment analysis of KEGG demonstrated that the 60 targets were enriched in 78 signaling pathways( min overlap: 3,P value cutoff: 0. 01,min enrichment: 1. 5),many of which are related to anti-bacteria,anti-inflammation and anti-virus,such as IL-17 signaling pathway,RIG-I-like receptor signaling pathway and NOD-like receptor signaling pathway. Finally,depending on the clinical activity of H. perforata,the relevant signaling pathways were analyzed through experimental data and literature. Dehydroconiferyl alcohol was reported to have the anti-inflammatory effect and perforamone D to possess the antimycobacterial activity. The KEGG pathway enrichment analysis showed that dehydroconiferyl alcohol could act on the Alzheimer's disease( AD) signaling pathway by targeting CDK5 R1 and BACE1. ACh E inhibitor is the most promising drug to treat AD,while dehydroconiferyl alcohol has been proved to inhibit ACh E according to literature. The experimental results revealed that the extract of leaves of H. perforata can effectively inhibit the growth of Staphylococcus aureus. These are consistent with the enrichment analysis results of KEGG. This study explored the bioactive components and pharmacodynamics of the leaves of the H. perforata,laying a theoretical foundation for its in-depth development and rational application.

Evaluation of in-vivo antidiarrhoeal and in-vitro antibacterial activities of the root extract of Brucea antidysenterica J. F. Mill (Simaroubaceae).

BACKGROUND: Diarrhoea has been the major cause of death especially in children of developing countries. Brucea antidysenterica is one of the several medicinal plants used traditionally for the treatment of diarrhoea in Ethiopia. Hence, the present study was undertaken to investigate the antidiarrhoeal and antibacterial activities of the root extract of B. antidysenterica. METHODS: Plant material was extracted by maceration technique using 80% methanol. The antidiarrhoeal activity was tested using castor oil-induced diarrhoea, castor oil-induced charcoal meal test, and castor oil-induced enteropooling models in mice. Whilst, the antibacterial activity of the crude extract was evaluated using agar well diffusion and broth microdilution methods. RESULTS: The 80% methanolic crude extract significantly delayed the diarrhoeal onset at the two higher doses (p < 0.001) and it has also inhibited the number and weight of faecal output at all tested doses as compared with the negative control. Moreover, it showed a significant anti-motility effect (p < 0.001) at all tested doses. Whereas it displayed a significant reduction in the weight and volume of intestinal contents at the doses of 200 and 400 mg/kg (p < 0.01). The highest concentration (800 mg/mL) of test extract showed maximum zone of inhibition in all tested standard strains of bacteria (18.3 mm-22 mm). While MIC and MBC values (0.39 mg/mL and 1.56 mg/mL) showed that S. flexneri was the most susceptible pathogen for test extract. CONCLUSION: The study revealed that the root extract of B. antidysenterica has antidiarrhoeal and antibacterial activities.

In vitro inhibition of protein glycation and advanced glycation end products formation by hydroethanolic extract and two fractions of Simaba trichilioides roots.

Long-term hyperglycemia maintenance is responsible for increased protein glycation and formation of advanced glycation end products (AGEs), both are associated with the onset of diabetes mellitus complications. Efforts have been made to discover new agents having antiglycation potential. The aim of this study was to investigate the effects of the hydroethanolic extract and the ethyl acetate and methanolic fractions of Simaba trichilioides roots on the formation of AGEs. In an in vitro model system of protein glycation, incubations with hydroethanolic extract, ethyl acetate or methanolic fractions of S. trichilioides decreased the fluorescent AGEs, and markers of tyrosine and tryptophan oxidation. Protein crosslinking was reduced in the presence of the ethyl acetate fraction of S. trichilioides. Simaba trichilioides roots seem to be a promising source of compounds having ability to prevent glycoxidation changes, with potential applications in complementary therapies for management of diabetic complications.

Traditional use and scientific investigations of the medicinal plant Simaba cedron Planch.

Simaba cedron Planch (Simaroubaceae) has frequently been reported as a traditional remedy against snake bites, malaria, gastrointestinal and other disorders. Starting in the 18th century, European physicians and researchers made several efforts to verify the reported virtues and to isolate active principles. Most important achievements are reviewed her. From modern investigations, an anti-malarial activity seems plausible due to the quassinoids contained. An effect against snake-bites seems questionable, research about the usefulness against gastrointestinal disorders, which is also reported, is missing. Other Simaroubaceae, however, are under current investigation now.

Involvement of Potassium Channels, Nitric Oxide Synthase, and Guanylate Cyclase in the Spasmolytic Effect of Simaba ferruginea A.St.-Hil on Rat Isolated Ileum.

BACKGROUND AND AIM: Simaba ferruginea A.St.-Hil. Popularly known as "calunga," is a typical Brazilian cerrado plant whose rhizomes are popular for treating diarrhea. AIMS: The aim of this study was to evaluate the spasmolytic activity and the antidiarrheal effect of the ethanolic extract obtained from S. ferruginea (Sf-EtOH). METHODS: Ileal segments (1-2 cm) from male Wistar rats were mounted in isolated organ baths and connected to a force transducer, and then to an amplifier which was connected to a computer (AVS Projetos/São Paulo-SP). After stabilization for 60 min, under tension (1 gf), two submaximal contractions were induced with KCl 40 mM or carbachol 10-6 M on ileal segments. During the third tonic and sustained contraction, Sf-EtOH was added in cumulative concentrations to the organ bath. Incubations with L-NAME (10-4 M), ODQ (10-5 M), TEA+ (5 or 1 mM), glibenclamide (10-5 M), or apamine (100 nM) were prepared (n = 5), separately and used to verify the involvement of the nitric oxide synthase, guanylate cyclase, and potassium channels in the relaxing effect. The results were expressed as mean ± standard error of the mean and were statistically evaluated using one-way ANOVA followed by Bonferroni test, when necessary *p < 0.05. RESULTS: Sf-EtOH promotes relaxation on rat isolated ileum pre-contracted with CCh and KCl in a concentration-dependent manner. Sf-EtOH also inhibited ileum contractions against cumulative concentrations of carbachol (CCh), KCl, and CaCl2, shifting the curves to the right in a non-parallel manner with an Emax reduction. In the presence of potassium channel blockers, Sf-EtOH shifted the curves to the right with a reduction of Emax, suggesting the involvement of BKCa, KATP, and SKCa in its spasmolytic effect. In the presence of L-NAME or ODQ, the relaxation curves were shifted to the right, suggesting the involvement of this pathway in Sf-EtOH spasmolytic effect. CONCLUSIONS: Sf-EtOH acts in a concentration-dependent manner, involving the positive modulation of K+ channels and NO pathway.

In vitro nematicidal effect of Chenopodium ambrosioides and Castela tortuosa n-hexane extracts against Haemonchus contortus (Nematoda) and their anthelmintic effect in gerbils.

The in vitro nematicidal effect of Chenopodium ambrosioides and Castela tortuosa n-hexane extracts (E-Cham and E-Cato, respectively) on Haemonchus contortus infective larvae (L3) and the anthelmintic effect of these extracts against the pre-adult stage of the parasite in gerbils were evaluated using both individual and combined extracts. The in vitro confrontation between larvae and extracts was performed in 24-well micro-titration plates. The results were considered 24 and 72 h post confrontation. The in vivo nematicidal effect was examined using gerbils as a study model. The extracts from the two assessed plants were obtained through maceration using n-hexane as an organic agent. Gerbils artificially infected with H. contortus L3 were treated intraperitoneally with the corresponding extract either individually or in combination. The results showed that the highest individual lethal in vitro effect (96.3%) was obtained with the E-Cham extract at 72 h post confrontation at 40 mg/ml, followed by E-Cato (78.9%) at 20 mg/ml after 72 h. The highest combined effect (98.7%) was obtained after 72 h at 40 mg/ml. The in vivo assay showed that the individual administration of the E-Cato and E-Cham extracts reduced the parasitic burden in gerbils by 27.1% and 45.8%, respectively. Furthermore, the anthelmintic efficacy increased to 57.3% when both extracts were administered in combination. The results of the present study show an important combined nematicidal effect of the two plant extracts assessed against L3 in gerbils.

12ß-Acetyloxyperforatin, a New Limonoid from Harrisonia Perforata.

A new A, D-seco limonoid, named 12-acetyloxyperforatin (1), along with three known ones, were isolated from the leaves of Harrisonia perforata. Their structures were elucidated on the basis of spectroscopic analysis, including extensive NMR techniques and computational modelling. These compounds showed no inhibitory activity against the 11ß-HSD1 enzyme.

Ailanthone exerts an antitumor function on the development of human lung cancer by upregulating microRNA-195.

BACKGROUND: Lung cancer is a common leading cause of cancer-related death worldwide. Ailanthone, a natural compound isolated from Chinese herb Ailanthus altissima, has been reported to exert antiproliferative effects on various cancer cells. METHODS: The present study aimed to investigate the role of ailanthone in the lung cancer cells and the correlation between the ailanthone and microRNA (miR)-195. The cell viability, proliferation, and apoptosis were determined by cell counting kit-8 assay, bromodeoxyuridine incorporation method, annexin V-fluorescein isothiocyanate/propidium iodide assay, respectively. Apoptosis- and autophagy-related proteins, as well as regulatory factors in the signaling pathways, were analyzed by Western blot method. The expression of miR-195 was quantified by quantitative reverse transcription-polymerase chain reaction. RESULTS: The results confirmed that ailanthone was involved in the lung cancer cell progress by inhibiting cell viability and proliferation, but promoted cell apoptosis and autophagy. We also found that ailanthone upregulated the expression of miR-195. Further, the downregulated miR-195 inhibited the apoptosis and autophagy induced by ailanthone. Moreover, our studies revealed that miR-195 inhibitor promoted the phosphorylation of PI3K, AKT, JAK, and STAT3, which was inhibited by ailanthone. CONCLUSION: All these findings suggest that ailanthone plays key roles in lung cancer progress and is closely correlated with miR-195 expression.

Assessment of toxicity and differential antimicrobial activity of methanol extract of rhizome of Simaba ferruginea A. St.-Hil. and its isolate canthin-6-one.

ETHNOPHARMACOLOGICAL RELEVANCE: Simaba ferruginea A. St.-Hil., Simaroubaceae, popularly known as "calunga" is a typical subtropical shrub used in Central Brazil mainly for infection, anti-inflammatory, analgesic and gastric duodenal-ulcers. It presents in its composition the alkaloid canthin-6-one, an alkaloid indole ß-carboxylic. AIM: This study aims to investigate the toxicity, antimicrobial activities of methanol extract of Simaba ferruginea (MESf) and canthin-6-one by using different experimental models. METHODS: The present study evaluated the phytochemical analysis by high performance liquid chromatography (HPLC), toxicological potential of MESf and canthin-6-one, using the cytotoxicity, genotoxicity assays with CHO-K1 cells and in vivo acute test in mice. Antimicrobial activity was evaluated by the broth microdilution assays, while the antimicrobial mechanism of action was also assessed using different in vitro bacterial and fungal models. RESULTS: The HPLC analysis of MESf revealed the presence of canthin-6-one, kaempferol and morin. Differential in vitro toxicities were observed between MESf and canthin-6-one. In the cytotoxicity assay, MESf presented toxicity against CHO-K1, while canthin-6-one did not. In the case of in vitro genotoxicity, both showed to be potentially genotoxic. In the in vivo toxicity study, both MESf (up to 1000 mg/kg) and cantin-6-one (up to 100 mg/kg) caused no toxicologically relevant alterations and are thus considered not to be toxic. MESf was shown to be relatively safe with NOAEL (100 mg/kg) when administrate in mice. Both MESf and canthin-6-one also showed differential antimicrobial activities. On one hand, MESf demonstrated good spectrum of antibacterial action against Staphylococcus aureus (MIC 12.5 µg/mL) and Escherichia coli (MIC 25 µg/mL) and moderate activity against Enterococcus faecalis and Shigella flexneri (MIC 200 µg/mL) but no antifungal effect. On the hand, canthin-6-one showed no antibacterial activity, except against Staphylococcus aureus (100 µg/mL), but potent in vitro fungicidal activity against clinically important Aspergillus niger and Candida species at MFC intervals ranging from 3.12 to 25 µg/mL. Both MESf and canthin-6-one were bacteriostatic in action. MESf antimicrobial mechanism of actions are associated with changes in the permeability of bacterial membranes, evidenced by the increased entry of hydrophobic antibiotic in Shigella flexneri, intense K+ efflux (Shigella flexneri, Staphylococcus aureus) and nucleotides leakage (Staphylococcus aureus). In the antifungal mode of action, canthin-6-one inhibited Saccharomyces cerevisiae growth and including alteration in the cell membrane of Neurospora crassa. CONCLUSION: The results of this work demonstrated the differential antimicrobial activities of MESf and its alkaloid isolate, canthin-6-one with antibacterial and antifungal activities, respectively. The present study support the popular use of Simaba ferruginea in combatting afflictions related to bacterial infections, and demonstrate that canthin-6-one as a promising antifungal agent. Both MESf and canthin-6-one are considered non-toxic based on the in vitro toxicological study.

Anti-plasmodial effect of plant extracts from Picrolemma huberi and Picramnia latifolia.

BACKGROUND: Malaria is an infectious disease caused by parasites of the genus Plasmodium, of which Plasmodium vivax and Plasmodium falciparum are the major species that cause the disease in humans. As there are relatively few alternatives for malaria treatment, it is necessary to search for new chemotherapeutic options. Colombia possesses a great diversity of plants, which are potential sources of new compounds of medical interest. Thus, in this study the antiplasmodial effect of extracts from two species of plants from the families Simaroubaceae and Picramniaceae (Picramnia latifolia and Picrolemma huberi) was evaluated in vitro and in vivo. These plants were chosen because they contain secondary metabolites with interesting medicinal effects. RESULTS: The ethanolic extracts of both species were highly active with IC50: 1.2 ± 0.19 µg/mL for P. latifolia and IC50: 0.05 ± 0.005 µg/mL for P. huberi. The P. latifolia extract had a stage specific effect on trophozoites and inhibited parasite growth in vivo by 52.1 ± 3.4%, evaluated at 1000 mg/kg in Balb/c mice infected with Plasmodium berghei. On the other hand, evaluated at 150 mg/kg body weight in the same murine model, the ethanolic extract from P. huberi had an antiplasmodial effect in all the asexual intraerythrocytic stages of P. falciparum FCR3 and inhibited the parasitic growth in 93 ± 32.9%. CONCLUSIONS: This is the first report of anti-malarial activity for these two species of plants. Thus, P. latifolia and P. huberi are potential candidates for the development of new drugs for treating malaria.

Glaucarubulone glucoside from Castela macrophylla suppresses MCF-7 breast cancer cell growth and attenuates benzo[a]pyrene-mediated CYP1A gene induction.

Quassinoids often exhibit antioxidant and antiproliferative activity. Emerging evidence suggests that these natural metabolites also display chemopreventive actions. In this study, we investigated the potential for the quassinoid glaucarubulone glucoside (Gg), isolated from the endemic Jamaican plant Castela macrophylla (Simaroubaceae), to display potent cytotoxicity and inhibit human cytochrome P450s (CYPs), particularly CYP1A enzymes, known to convert polyaromatic hydrocarbons into carcinogenic metabolites. Gg reduced the viability of MCF-7 breast adenocarcinoma cells (IC50 = 121 nm) to a greater extent than standard of care anticancer agents 5-fluorouracil, tamoxifen (IC50 >10 µm) and the tamoxifen metabolite 4-hydroxytamoxifen (IC50 = 2.6 µm), yet was not cytotoxic to non-tumorigenic MCF-10A breast epithelial cells. Additionally, Gg induced MCF-7 breast cancer cell death. Gg blocked increases in reactive oxygen species in MCF-10A cells mediated by the polyaromatic hydrocarbon benzo[a]pyrene (B[a]P) metabolite B[a]P 1,6-quinone, yet downregulated the expression of genes that promote antioxidant activity in MCF-7 cells. This implies that Gg exhibits antioxidant and cytoprotective actions in non-tumorigenic breast epithelial cells and pro-oxidant, cytotoxic actions in breast cancer cells. Furthermore, Gg inhibited the activities of human CYP1A according to non-competitive kinetics and attenuated the ability of B[a]P to induce CYP1A gene expression in MCF-7 cells. These data indicate that Gg selectively suppresses MCF-7 breast cancer cell growth without impacting non-tumorigenic breast epithelial cells and blocks B[a]P-mediated CYP1A induction. Taken together, our data provide a rationale for further investigations of Gg and similar plant isolates as potential agents to treat and prevent breast cancer. Copyright © 2017 John Wiley & Sons, Ltd.

(±)-Perforison A, A Pair of New Chromone Enantiomers from Harrisonia perforata.

(+)-Perforison A and (-)-perforison A, a new pair of chromone enantiomers, along with four known compounds, were isolated from the leaves and stems of Harrisonia perforata. Their structures and absolute configurations were determined on the basis of extensive analysis of spectroscopic data and electronic circular dichroism (ECD) calculations. The cytotoxic activities in vitro of these compounds were evaluated, but none showed significant activity.

16-nor Limonoids from Harrisonia perforata as promising selective 11ß-HSD1 inhibitors.

Two new 16-nor limonoids, harperspinoids A and B (1 and 2), with a unique 7/5/5/6/5 ring system, have been isolated from the plant Harrisonia perforate together with a known one, Harperforin G (3). Their structures were elucidated by NMR spectroscopy, X-ray diffraction analysis and computational modelling. Compound 1 exists as polymorphic crystals. Conformations of 1 in solution were further discussed based on the computational results. These compounds exhibited notable inhibitory activity against the 11ß-HSD1 enzyme. Compound 3 had potencies for the inhibition of human 11ß-HSD1 with high selectivity against 11ß-HSD2 (IC50 0.58 µM, SI > 174). Molecular docking and quantitative structure-activity relationship studies revealed a mixed regulatory mechanism.

The quassinoid isobrucein B reduces inflammatory hyperalgesia and cytokine production by post-transcriptional modulation.

Isobrucein B (1) is a quassinoid isolated from the Amazonian medicinal plant Picrolemma sprucei. Herein we investigate the anti-inflammatory and antihyperalgesic effects of this quassinoid. Isobrucein B (1) (0.5-5 mg/kg) inhibited carrageenan-induced inflammatory hyperalgesia in mice in a dose-dependent manner. Reduced hyperalgesia was associated with reduction in both neutrophil migration and pronociceptive cytokine production. Pretreatment with 1 inhibited in vitro production/release of cytokines TNF, IL-1ß, and KC/CXCL1 by lipopolysaccharide-stimulated macrophages. To investigate its molecular mechanism, RAW 264.7 macrophages with a luciferase reporter gene controlled by the NF-κB promoter were used (RAW 264.7-Luc). Quassinoid 1 reduced the luminescence emission by RAW 264.7-Luc stimulated by different compounds. Unexpectedly, NF-κB translocation to macrophage nuclei was not inhibited by 1 when evaluated by Western blotting and immunofluorescence. Furthermore, quassinoid 1 did not change the levels of TNF mRNA transcription in stimulated macrophages, suggesting post-transcriptional modulation. In addition, constitutive expression of luciferase in RAW 264.7 cells transiently transfected with a plasmid containing a universal promoter was inhibited by 1. Thus, isobrucein B (1) displays anti-inflammatory and antihyperalgesic activities by nonselective post-transcriptional modulation, resulting in decreased production/release of pro-inflammatory cytokines and neutrophil migration.

[Chemical constituents from the twigs and leaves of Harrisonia perforate].

This study was performed to investigate the chemical constituents in the twigs and leaves of Harrisonia perforate. Six compounds were isolated from the 95% EtOH extract of the twigs and leaves of Harrisonia perforate by silica gel, ODS, Sephadex LH-20 column chromatographies and preparative HPLC. On the basis of chemical properties and spectra data, these compounds were identified as harriperfin E (1), kihadanin A (2), kihadanin B (3), 6α-acetoxyobacunol acetate (4), gardaubryone C (5), and ß-sitosterol methyl ether (6), respectively. Compound 1 is a new chromone, and compounds 2-6 are isolated from this plant for the first time.