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1.
Chem Biodivers ; 21(5): e202400283, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38485665

RESUMO

Fifteen bibenyls and four fluorenones, including five new bibenzyl-phenylpropane hybrids, were isolated from the aerial part of Dendrobium nobile Lindl. Their structures were determined by spectroscopic methods. Bioassay on the LPS-induced proliferations of mouse splenic B lymphocytes, and Con A-induced T lymphocytes showed that compounds 1, 2, and 14 showed excellent immunosuppressive activities with IC50 values of 1.23, 1.01, and 3.87 µM, respectively, while compounds 3-4, 7, 10, 13, and 15 exhibited moderate immunosuppressive activities with IC50 values ranging from 6.89 to 14.2 µM.


Assuntos
Bibenzilas , Proliferação de Células , Dendrobium , Imunossupressores , Dendrobium/química , Animais , Camundongos , Imunossupressores/farmacologia , Imunossupressores/química , Imunossupressores/isolamento & purificação , Bibenzilas/química , Bibenzilas/farmacologia , Bibenzilas/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Relação Dose-Resposta a Droga , Concanavalina A/antagonistas & inibidores , Concanavalina A/farmacologia
2.
Fitoterapia ; 152: 104926, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33991602

RESUMO

Dengratiol A (1), an unprecedented bibenzyl derivative bearing a tropolone unit together with three pairs of bibenzyl enantiomers (±)-dengratiols B-D [(±)-2-(±)-4], were isolated from Dendrobium gratiossimum Rchb.f. The resolution of enantiomers was performed with chiral HPLC. Their structures were characterized by extensive spectroscopic data analysis and calculated electronic circular dichroism (ECD). A hypothetical biosynthetic pathway for 1 is proposed. Biological assay revealed that (-)-2 showed moderate antiviral effect against IAV with IC50 value of 6.3 µM, and (±)-2 displayed cytotoxic activities against five human tumor cell lines with IC50 values ranging from 15.5 to 42.5 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Dendrobium/química , Antineoplásicos Fitogênicos/isolamento & purificação , Bibenzilas/isolamento & purificação , Linhagem Celular Tumoral , China , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Caules de Planta/química
3.
J Nat Prod ; 84(5): 1459-1468, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33913326

RESUMO

An EtOH extract of the Chinese liverwort Radula apiculata showed cytotoxic activity against the A549 lung cancer cell line. Bioassay-guided fractionation led to the isolation of 19 prenylated bibenzyls, including eight previously unknown dimeric prenylated bibenzyls [radulapins A-H (1-8)], four new prenylated bibenzyls (9-12), and seven known compounds (13-19). Compounds 1-11 were analyzed as racemates by chiral-phase separation. Their structures were determined by detailed analysis of their spectroscopic data and by single-crystal X-ray diffraction, chiral resolutions, and electronic circular dichroism measurements. Using an MTT assay, these dimers (1-8) showed significant cytotoxic activity against a panel of human cancer cell lines. Further investigation revealed that compound 4 induces PC-3 cell death via mitochondrial-derived apoptosis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Hepatófitas/química , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Bibenzilas/isolamento & purificação , China , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estrutura Molecular , Células PC-3 , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Prenilação , Estereoisomerismo
4.
Drug Des Devel Ther ; 14: 3301-3313, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848368

RESUMO

OBJECTIVE: To investigate the effect of erianin on tumor growth and immune response in human colorectal cancer cells (CRC). METHODS: The effect of erianin on tumor growth was determined by CCK8 and colony formation assay. Western blotting was used to evaluate the expression levels of relevant proteins and qRT-PCR was used to evaluate the mRNA level of the relevant gene. The transcriptional activity of ß-catenin was determined by dual-luciferase reporter assay. Cellular thermal shift assay was used to quantify drug-target interactions. The cell surface CD47 was assessed by flow cytometry. The enrichment of H3K27 acetyl marks on CD47 promoter was evaluated by chromatin immunoprecipitation assay. Phagocytosis assay was used to determine the phagocytic activity of macrophage. In vivo role of erianin was studied on xenograft models. RESULTS: We found that erianin significantly decreased cell survival, colony formation, induced cell cycle arrest, and led to cell apoptosis in SW480 and HCT116 cells. Mechanism analysis demonstrated that erianin inhibited the nuclear translocation and transcriptional activity of ß-catenin, which might result from erianin-ß-catenin interaction. In addition, the downstream gene expressions, such as c-Myc and cyclin D1, was decreased. More interestingly, erianin decreased the expression of CD47 by regulating H3K27 acetyl marks enrichment on CD47 promoter. Consequently, macrophage-mediated phagocytosis was increased. Our in vivo experiments further confirmed the inhibitory effect of erianin on tumor growth. CONCLUSION: In summary, erianin could inhibit CRC cells growth and promoted phagocytosis, which suggested erianin as a potential therapeutic strategy for CRC patients.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Fagocitose/efeitos dos fármacos , Fenol/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Bibenzilas/química , Bibenzilas/isolamento & purificação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Dendrobium/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Fenol/química , Fenol/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
Fitoterapia ; 142: 104497, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32058054

RESUMO

Five previously undescribed compounds, including two dendrobine-type alkaloids (1 and 2), three bibenzyl derivatives (3-5), along with six known compounds were isolated from orchids Dendrobium findlayanum. The structures and absolute configurations of the undescribed compounds were elucidated on the basis of HR-ESIMS, NMR spectroscopy, optical rotation value, as well as electronic circular dichroism (ECD) calculations. The cytotoxic effects of the isolated compounds on three human tumour cell lines (A172, SHSY5Y, and Hela) were evaluated by the MTT assay. Compound 6 showed excellent inhibitory activities against three human tumour cell lines with IC50 ranging from 1.65 µM to 3.77 µM. All these compounds were assessed for their activity of promoting the gastrointestinal motility of zebrafish treated with Nile red. Compound 6 have excellent activity to promote the gastrointestinal motility of zebrafish at the concentration of 0.3 µM.


Assuntos
Alcaloides/química , Bibenzilas/química , Dendrobium/química , Alcaloides/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fármacos Gastrointestinais/química , Fármacos Gastrointestinais/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Humanos , Larva/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Peixe-Zebra
6.
Nat Prod Res ; 34(12): 1694-1701, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30580616

RESUMO

Phytochemical investigation of the whole plant of Dendrobium scabrilingue resulted in the isolation of two new compounds namely dendroscabrols A (1) and B (2), along with eight known compounds (3-10). The structures of these compounds were determined by NMR and HR-ESI-MS experiments. All of the isolates were evaluated for their α-glucosidase inhibitory effect. Dendroscabrol B (2) and RF-3192C (10) showed the most potent α-glucosidase inhibitory activity. Dendroscabrol A (1), gigantol (5), coelonin (7) and lusianthridin (9) also exhibited strong activity as compared with the positive control acarbose.


Assuntos
Bibenzilas/isolamento & purificação , Dendrobium/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Fenantrenos/isolamento & purificação , Bibenzilas/química , Bibenzilas/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Estrutura Molecular , Fenantrenos/química , Fenantrenos/farmacologia , Extratos Vegetais/química , alfa-Glucosidases/efeitos dos fármacos
7.
Nat Prod Res ; 34(4): 563-566, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30394105

RESUMO

The stems of Dendrobium huoshanense have long been used to prevent various diseases, including inflammatory diseases. This study was aimed to explain the anti-inflammatory effect of D. huoshanense stems in LPS-induced RAW 264.7 macrophages and to discover potential anti-inflammatory compounds. Results exhibited that D. huoshanense stems ethanol extract could significantly inhibit LPS-induced production of NO, TNF-α and IL-1ß. Based on bioassay guided strategy, four bibenzyls (1-4) were isolated from D. huoshanense stems for the first time. Anti-inflammatory assay showed 1-4 could remarkably inhibit the production of NO in LPS-induced macrophages. Moreover, quantitative RT-PCR analysis displayed that the mRNA levels of iNOs, TNF-α and IL-1ß could also be significantly reduced by 1-4. These results suggested that D. huoshanense stems ethanol extract and bibenzyls 1-4 might be well developed as therapeutic agent to prevent inflammatory diseases.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Bibenzilas/isolamento & purificação , Dendrobium/química , Macrófagos/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Bibenzilas/farmacologia , Bioensaio/métodos , Etanol , Interleucina-1beta/genética , Lipopolissacarídeos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7/citologia , RNA Mensageiro/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética
8.
Biosci Biotechnol Biochem ; 84(1): 31-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31794330

RESUMO

4-(2-Hydroxyphenethyl)-2,6-dimethoxyphenol, a bibenzyl, was isolated from the leaves of Empetrum nigrum var. japonicum, collected from Mount Tateyama. Japanese rock ptarmigans frequently eat the leaves and fruits of this plant. The structure of the bibenzyl was confirmed by NMR spectroscopic analysis and fully characterized. A synthesis of this compound was accomplished by coupling 2-hydroxyphenylacetic acid with syringaldehyde, decarboxylation of the resultant isoaurones, and hydrogenation of the double bond in the corresponding stilbene. This compound displayed cytotoxic activity against human cancer cells (HCT116 and Hela cells) and leukemia cells (HL-60 cells). The present study suggests that this plant serves as a source of biologically active natural products. Also, our findings provide information on the secondary metabolites in the diet of Japanese rock ptarmigans.


Assuntos
Bibenzilas/síntese química , Bibenzilas/farmacologia , Ericaceae/química , Extratos Vegetais/síntese química , Extratos Vegetais/farmacologia , Bacillus subtilis/efeitos dos fármacos , Bibenzilas/química , Bibenzilas/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Células HCT116 , Células HL-60 , Células HeLa , Humanos , Japão , Espectroscopia de Ressonância Magnética , Conformação Molecular , Neoplasias/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Pirogalol/análogos & derivados , Pirogalol/química
9.
Fitoterapia ; 138: 104350, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473333

RESUMO

Three new bibenzyl derivatives (bletstrins A-C, 1-3), including two bibenzyls that have hydroxyl-substituted chiral centers on the aliphatic bibenzyl bridge, along with eighteen known stilbenoids (4-21) were isolated from the tubers of Bletilla striata. The structures of new compounds were elucidated by the use of 1D/2D NMR spectroscopic data. The absolute configurations of bletitrins A and B were determined by optical rotation value. Compounds 13-16 were isolated from the Orchidaceae for the first time. Most of the isolated compounds were evaluated for their antibacterial activities against three gram-positive bacterial strains and one gram-negative bacterial strain. Compounds 4, 10, 12, 14, 15, 16 and 18 showed potent inhibitory activities, with MICs of (6-52 µg/mL) against S. aureus ATCC 6538.


Assuntos
Antibacterianos/farmacologia , Orchidaceae/química , Tubérculos/química , Estilbenos/farmacologia , Antibacterianos/isolamento & purificação , Bibenzilas/isolamento & purificação , Bibenzilas/farmacologia , China , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Estilbenos/isolamento & purificação
10.
Fitoterapia ; 138: 104313, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421147

RESUMO

Bulbocodioidins E-H (1-4), four pairs of undescribed racemic bi(9,10-dihydro)phenanthrene and phenanthrene/bibenzyl atropisomers, along with four known compounds (5-8) were isolated from the ethanol extract of the pseudobulbs of Pleione bulbocodioides. Their structures were established by HRESIMS and comprehensive NMR spectroscopic data analysis. Their absolute configurations were elucidated by comparison of their experimental and calculated ECD (electronic circular dichroism) curves. Furthermore, compound 4a displayed cytotoxic activity against colon cancer (HCT-116), liver cancer (HepG2), and breast cancer (MCF-7) cell lines with IC50 values of 7.6, 3.8 and 3.4 µM, respectively. Compound 6 showed cytotoxic activity against breast cancer cell lines (MCF-7) with IC50 value of 5.4 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Orchidaceae/química , Fenantrenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Bibenzilas/isolamento & purificação , China , Células HCT116 , Células Hep G2 , Humanos , Células MCF-7 , Estrutura Molecular , Fenantrenos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química
11.
J Nat Prod ; 82(7): 1741-1751, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31268321

RESUMO

Nine new prenylated bibenzyls, radstrictins A-I (1-9), and 11 known congeners were obtained from the Chinese liverwort Radula constricta. Their structures were identified by analysis of HRMS, NMR, and electronic circular dichroism data. Radstrictins A-F (1-6) were isolated as a racemate or scalemic mixtures. All the isolated compounds were subjected to cytotoxicity assessment. Methyl 2,4-dihydroxy-3-(3-methyl-2-butenyl)-6-phenethylbenzoate (10) exhibited significant activity against human lung cancer cell lines A549 and NCI-H1299 with IC50 values of 6.0 and 5.1 µM, respectively. Further research revealed that cell death triggered by 10 occurred via mitochondria-derived paraptosis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Bibenzilas/isolamento & purificação , Bibenzilas/farmacologia , Hepatófitas/química , Mitocôndrias/efeitos dos fármacos , Prenilação , Bibenzilas/química , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Análise Espectral/métodos
12.
Toxicol Appl Pharmacol ; 371: 41-54, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30946863

RESUMO

Erianin, a component extracted from the traditional Chinese herbal medicine Dendrobium, has shown significant anti-tumour activity in various cancers but not in bladder cancer. In this study, we assessed the effects of Erianin on bladder cancer growth and elucidated the related mechanisms. First, Erianin was synthesized with high yields, and markedly suppressed EJ and T24 cell proliferation. It induced G2/M-phase arrest in vitro. Furthermore, Erianin triggered apoptosis via caspase cascades activation and the mitochondrial-mediated apoptotic pathway. Bim up-regulation and Bcl-2 down-regulation as the symbol of apoptosis which were found to play the dominant role in the effects of Erianin. We further showed that JNK pathway activation is necessary for the Erianin-mediated anti-proliferation and apoptotic response. Finally, Erianin exhibited anti-tumour activity and induced apoptosis in tumour tissue in vivo. Collectively, these results suggest that Erianin induced cell cycle G2/M-phase arrest and apoptosis via the JNK signalling pathway in bladder cancer, indicating the potential usefulness of Erianin for the therapy of bladder cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bibenzilas/farmacologia , Proliferação de Células/efeitos dos fármacos , Dendrobium , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitocôndrias/efeitos dos fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Antineoplásicos/isolamento & purificação , Proteína 11 Semelhante a Bcl-2/genética , Proteína 11 Semelhante a Bcl-2/metabolismo , Bibenzilas/isolamento & purificação , Linhagem Celular Tumoral , Dendrobium/química , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Camundongos Nus , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Fenol , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Neoplasias da Bexiga Urinária/enzimologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Fitoterapia ; 129: 241-248, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30055233

RESUMO

Ten previously undescribed stilbenoids, including six bibenzyls (bleochrins A-F, 1-6), three phenanthrenes derivatives (bleochrins G-J, 7-10) along with eleven known compounds were isolated from the rhizomes of Bletilla ochracea Schltr. The structural characterizations of 1-21 were accomplished by spectroscopic data, while the absolute stereostructure of 6 was confirmed by electronic circular dichroism (ECD) data analyses. All isolated metabolites except 7 were evaluated for cytotoxic activity against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW480). Four isolates exhibited significant inhibitory ability against HL-60, SMMC-7721, and MCF-7 cell lines, with IC50 values ranging from 0.79 to 6.57 µM. The isolates were tested further for inhibitory effects on the NO production of the liposaccharide (LPS)-induced RAW264.7 macrophages and showed activity with IC50 values at 15.29-24.02 µM.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Orchidaceae/química , Fenantrenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Bibenzilas/isolamento & purificação , Linhagem Celular Tumoral , China , Humanos , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Fenantrenos/isolamento & purificação , Células RAW 264.7 , Rizoma/química
14.
Fitoterapia ; 127: 74-80, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29421240

RESUMO

Four new dihydrophenanthrenofuran, bleochranols A-D (1-4), along with 21 known compounds including phenanthrenes (5-14) and bibenzyls (15-25) were isolated and elucidated from the rhizomes of Bletilla ochracea. Combination of 1D/2D NMR techniques and the Electronic Circular Dichroism (ECD) spectroscopy based on the empirical helicity rules, chemical structure of those isolates were determined. All the compounds were evaluated for cytotoxicity against HL-60, SMMC-7721, A-549, MCF-7 and SW480 human cancer cell lines by MTS assay and anti-inflammatory activity by nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophages. Among the 25 tested compounds, bleochranol A (1) showed remarkable cytotoxic activity against HL-60, A-549, and MCF-7 with IC50 values of 0.24 ±â€¯0.03, 3.51 ±â€¯0.09 and 3.30 ±â€¯0.99 µM respectively. The anti-inflammatory assay showed that compound 12 exhibited most potential activity against NO production in RAW 264.7 macrophages with IC50 2.86 ±â€¯0.17 µM. The results indicated that the main chemical constituents of B. ochracea were phenanthrene and bibenzyl and similar to that of B. striata.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Orchidaceae/química , Estilbenos/isolamento & purificação , Animais , Anti-Inflamatórios/farmacologia , Bibenzilas/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Fenantrenos/isolamento & purificação , Extratos Vegetais/química , Células RAW 264.7 , Rizoma/química , Estilbenos/farmacologia
15.
Nat Prod Res ; 32(20): 2447-2451, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29284299

RESUMO

A new phenanthrene, bobulretin A (1), and a new 9,10-dihydrophenanthrene, bobulretin B (2) along with four known bibenzyls (3-6) were isolated from the whole plants of Bulbophyllum retusiusculum. Their structures were elucidated by means of extensive spectroscopic analysis. Bobulretin B (2), isolated as enantiomer mixture with unequal proportions, was verified by analysis on a chiral OD-H HPLC column. Compounds 1, 3 and 4 were evaluated for their α-glucosidase inhibitory activity. Neither of them showed obvious activity.


Assuntos
Orchidaceae/química , Fenantrenos/química , Bibenzilas/química , Bibenzilas/isolamento & purificação , China , Estrutura Molecular , Fenantrenos/isolamento & purificação , alfa-Glucosidases
16.
J Asian Nat Prod Res ; 20(4): 385-390, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28617053

RESUMO

A novel glucoside bletilloside A (1) was isolated from the tubers of Bletilla striata, together with seven known compounds (2-8). Their structures were determined on the basis of extensive spectroscopic analyses. All compounds were evaluated for the inhibition on NO production effects in RAW 264.7 macrophage cells, while militarine (4) and dactylorhin A (5) exhibited moderate inhibitory effects.


Assuntos
Bibenzilas/isolamento & purificação , Bibenzilas/farmacologia , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Orchidaceae/química , Animais , Bibenzilas/química , Glucosídeos/química , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Tubérculos/química
17.
Fitoterapia ; 122: 95-100, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28882670

RESUMO

Two new bisbibenzyls, heudelotol A (1) and B (2), along with the known bibenzyls, (E)-combretastatin A-1 (3) and combretastatin B-1 (4) have been isolated from the ethyl acetate extract of the roots of Dichapetalum heudelotii. Structure elucidation of all four isolated compounds was achieved using UV, IR, 1D and 2D NMR spectroscopy and HR-Mass Spectrometry. The compounds exhibited varying antiproliferative activity against six cancer cell lines using the CellTiter-Glo® Luminiscent Cell Viability Assay. Compound 3 was found to be the most active with sub-micromolar growth inhibition concentrations against all the cell lines (GI50 0.03-0.72µM). However, it was about ten-fold less active than the positive control, taxol. The new bisbibenzyls heudelotol A and B exhibited good activity against human pancreatic adenocarcinoma (GI50 9.04µM) and Burkitt's lymphoma (GI50 4.67µM) respectively, and average activity against the other cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Magnoliopsida/química , Estilbenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Bibenzilas/isolamento & purificação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Raízes de Plantas/química , Estilbenos/isolamento & purificação
18.
Bioorg Chem ; 72: 130-147, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28460355

RESUMO

The combretastatins are isolated from South African tree combretum caffrum kuntze. The lead compound combretastatin A-4 has displayed remarkable cytotoxic effect in a wide variety of preclinical tumor models and inhibits tubulin polymerization by interacting at colchicine binding site of microtubule. However, the structural simplicity of C A-4 is favorable for synthesis of various derivatives projected to induce rapid and selective vascular shutdown in tumors. Majority of the molecules have shown excellent antiproliferative activity and are able to inhibit tubulin polymerization as well as possible mechanisms of action have been investigated. In this review article, the synthesis and structure-activity relationships of C A-4 and immense number of its synthetic derivatives with various modifications on the A, B-rings, bridge carbons and their anti mitotic activities are discussed.


Assuntos
Bibenzilas/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Polimerização/efeitos dos fármacos , Tubulina (Proteína)/metabolismo , Animais , Bibenzilas/química , Bibenzilas/isolamento & purificação , Humanos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , África do Sul
19.
Chem Pharm Bull (Tokyo) ; 65(3): 295-299, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28250350

RESUMO

Four new prenylated bibenzyls, named aglaiabbrevins A-D (2, 4-6), were isolated from the leaves of Aglaia abbreviata, along with two known related analogues, 3,5-dihydroxy-2-[3,7-dimethyl-2(E),6-octadienyl]bibenzyl (7) and 3,5-dihydroxy-2-(3-methyl-2-butenyl)bibenzyl (8). The structures of the new compounds were elucidated on the basis of extensive spectroscopic experiments, mainly one and two dimensional (1D- and 2D)-NMR, and the absolute configuration of 5 was determined by the measurement of specific rotation. The isolated compounds were evaluated for their protein tyrosine phosphatase-1B (PTP1B) inhibitory activity. The results showed that compounds 5-7 exhibited more potent PTP1B inhibitory effects with IC50 values of 2.58±0.52, 2.44±0.35, and 2.23±0.14 µM, respectively, than the positive control oleanolic acid (IC50=2.74±0.20 µM). On the basis of the data obtained, these bibenzyls with the longer C-2 prenyl groups may be considered as potential lead compounds for the development of new anti-obesity and anti-diabetic agents. Also, the PTP1B inhibitory effects for prenylated bibenzyls are being reported for the first time.


Assuntos
Aglaia/química , Bibenzilas/farmacologia , Inibidores Enzimáticos/farmacologia , Folhas de Planta/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Bibenzilas/química , Bibenzilas/isolamento & purificação , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Estrutura Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Relação Estrutura-Atividade
20.
J Ethnopharmacol ; 198: 255-261, 2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28104409

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dendrobium. chrysotoxum Lindl is a commonly used species of medicinal Dendrobium which belongs to the family of Orchidaceae, locally known as "Shihu" or "Huangcao". D. chrysotoxum Lindl is widely known for medicinal values in traditional Chinese medicine as it possesses anti-inflammatory, anti-hyperglycemic induction, antitumor and antioxidant properties. STUDY AIM: To characterize the interaction between gigantol extracted from D. chrysotoxum Lindl and the AR gene, and determine gigantol's efficacy against cataractogenesis. MATERIALS AND METHODS: Human lens epithelial cells (HLECs) were induced by glucose as the model group. Reverse transcription polymerase chain reaction (RT-PCR) was used to assess AR gene expression. Then, the mode of interaction of gigantol with the AR gene was evaluated by UV-visible spectroscopy, atomic force microscope (AFM) and surface-enhanced Raman spectroscopy (SERS). The binding constant was determined by UV-visible. RESULTS: Gigantol depressed AR gene expression in HLECs. UV-visible spectra preliminarily indicated that interaction between the AR gene and gigantol may follow the groove mode, with a binding constant of 1.85×103L/mol. Atomic force microscope (AFM) data indicated that gigantol possibly bound to insert AR gene base pairs of the double helix. Surface-enhanced Raman spectroscopy (SERS) studies further supported these observations. CONCLUSION: Gigantol extracted from D. chrysotoxum Lindl not only has inhibitory effects on aldose reductase, but also inhibits AR gene expression. These findings provide a more comprehensive theoretical basis for the use of Dendrobium for the treatment of diabetic cataract.


Assuntos
Aldeído Redutase/genética , Bibenzilas/farmacologia , Catarata/prevenção & controle , Dendrobium/química , Guaiacol/análogos & derivados , Bibenzilas/isolamento & purificação , Catarata/etiologia , Células Cultivadas , Complicações do Diabetes/prevenção & controle , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/enzimologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Guaiacol/isolamento & purificação , Guaiacol/farmacologia , Humanos , Cristalino/citologia , Cristalino/efeitos dos fármacos , Cristalino/enzimologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Espectral Raman
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