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1.
Plants (Basel) ; 13(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38674483

RESUMO

Olibanum, a golden oleo-gum resin from species in the Boswellia genus (Burseraceae family), is a famous traditional herbal medicine widely used around the world. Previous phytochemical studies mainly focused on the non-polar fractions of olibanum. In this study, nine novel diterpenoids, boswellianols A-I (1-9), and three known compounds were isolated from the polar methanolic fraction of the oleo-gum resin of Boswellia carterii. Their structures were determined through comprehensive spectroscopic analysis as well as experimental and calculated electronic circular dichroism (ECD) data comparison. Compound 1 is a novel diterpenoid possessing an undescribed prenylmaaliane-type skeleton with a 6/6/3 tricyclic system. Compounds 2-4 were unusual prenylaromadendrane-type diterpenoids, and compounds 5-9 were new highly oxidized cembrane-type diterpenoids. Compounds 1 and 5 showed significant transforming growth factor ß (TGF-ß) inhibitory activity via inhibiting the TGF-ß-induced phosphorylation of Smad3 and the expression of fibronectin and N-cadherin (the biomarker of the epithelial-mesenchymal transition) in a dose-dependent manner in LX-2 human hepatic stellate cells, indicating that compounds 1 and 5 should be potential anti-fibrosis agents. These findings give a new insight into the chemical constituents of the polar fraction of olibanum and their inhibitory activities on the TGF-ß/Smad signaling pathway.

2.
ACS Appl Mater Interfaces ; 15(46): 53228-53241, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37943281

RESUMO

Nonapoptotic ferroptosis is a promising cancer treatment which offers a solution to the multidrug resistance of conventional apoptosis-induced programmed cancer cell death therapies. Reducing intracellular glutathione (GSH) is essential for inducing excess ROS and has been considered a crucial process to trigger ferroptosis. However, treatments reducing GSH alone have not produced satisfactory effects due to their restricted target. In this regard, FeCDs (Fe3+-modified l-histidine -sourced carbon dots) with dual GSH-consumption capabilities were constructed to engineer ferroptosis by self-amplifying intratumoral oxidative stress. Carbon dots have the ability to consume GSH, and the introduction of Fe3+ can amplify the GSH-consuming ability of CDs, reacting with excess H2O2 in the tumor microenvironment to generate highly oxidized •OH. This is a novel strategy through synergistic self-amplification therapy combining Fe3+ and CDs with GSH-consuming activity. The acid-triggered degradation material (FeCDs@PAE-PEG) was prepared by encapsulating FeCDs in an oil-in-water manner. Compared with other ferroptosis-triggering nanoparticles, the established FeCDs@PAE-PEG is targeted and significantly enhances the consumption efficiency of GSH and accumulation of excess iron without the involvement of infrared light and ultrasound. This synergistic strategy exhibits excellent ferroptosis-inducing ability and antitumor efficacy both in vitro and in vivo and offers great potential for clinical translation of ferroptosis.


Assuntos
Ferroptose , Neoplasias , Humanos , Peróxido de Hidrogênio , Apoptose , Carbono , Glutationa , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio , Microambiente Tumoral
3.
J Asian Nat Prod Res ; 25(1): 95-101, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35291901

RESUMO

A phytochemical investigation of Menispermum dauricum led to the isolation of five oxoisoaporphine-type alkaloids (1-5) and five aporphine-type alkaloids (6-10), including a novel oxoisoaporphine-type alkaloid: menispeimin A (1). Their structures were elucidated by spectroscopic studies including MS, 1 D and 2 D NMR, and confirmed by comparing with literature data. Among them, alkaloids 4-10 were obtained for the first time from Menispermum genus. Natural products 2, 4 and 6 exhibited significant cytotoxic activity against A549, Bel-7402 and MCF-7 cell lines.


Assuntos
Alcaloides , Antineoplásicos , Menispermum , Alcaloides/química , Espectroscopia de Ressonância Magnética , Menispermum/química , Menispermum/toxicidade , Rizoma/química
4.
Biomed Pharmacother ; 155: 113705, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36271541

RESUMO

Lung cancer is the leading cause of cancer-related death worldwide. The development of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and immune checkpoint inhibitors (ICIs) has brought favorable survival benefits to patients with non-small-cell lung cancer (NSCLC); unfortunately, acquired drug resistance remains a major barrier to the treatment of NSCLC. Recent studies have demonstrated that the transcriptional co-activator with a PDZ-binding motif (TAZ, also called WWTR1) induces tumor immune evasion by directly modulating the expression of programmed death ligand 1 (PD-L1), a key therapeutic target for checkpoint immunotherapy. Moreover, aberrant activation of TAZ is also a major mechanism of acquired resistance to EGFR-TKIs in NSCLC. Therefore, TAZ signaling blockade might be an effective strategy to overcome resistance to ICIs and EGFR-TKIs in NSCLC. In this study, we showed for the first time that artesunate effectively reduced TAZ and PD-L1 expression in NSCLC. We further demonstrated that artesunate suppressed TAZ/PD-L1-induced T-cell growth inhibition in vitro and enhanced anti-tumor immunity by recruiting infiltrating CD8 + T-cells in syngeneic mouse models. Artesunate also inhibited the stem cell-like properties of NSCLC cells and suppressed tumor growth in xenografts bearing gefitinib-resistant tumors. In addition, our results of molecular docking and cellular thermal shift assay analysis suggested that artesunate might directly target the TAZ-TEAD complex and induce proteasome-dependent TAZ degradation in NSCLC cells. These results suggest that artesunate enhanced anti-tumor immunity and overcame EGFR-TKI resistance in NSCLC at least in part by suppressing TAZ/PD-L1 signaling.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Camundongos , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/patologia , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Artesunato/farmacologia , Artesunato/uso terapêutico , Receptores ErbB/metabolismo , Inibidores de Checkpoint Imunológico , Simulação de Acoplamento Molecular , Complexo de Endopeptidases do Proteassoma , Resistencia a Medicamentos Antineoplásicos , Inibidores de Proteínas Quinases/farmacologia , Fatores de Transcrição/metabolismo , Mutação
5.
Biomed Pharmacother ; 153: 113319, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35753261

RESUMO

As a characteristic transcription factor in solid tumors, hypoxia inducible factor-1 (HIF-1) acts as a master regulator in breast cancer progression. Cryptolepine, as a natural alkaloid, noticeably inhibited HIF-1 transcriptional activity and decreased the protein expression of hypoxia-induced HIF-1α in breast cancer cells. Further study showed that cryptolepine blocked HIF-1-mediated glycolysis and suppressed the expression of multiple glycolysis enzymes, resulting in a decrease in ATP production in hypoxic T47D and 4T1 cells. Meanwhile, cryptolepine displayed potent suppressive effect on tumor growth in a dose-dependent manner. In 4T1 tumor xenografts, cryptolepine reduced HIF-1α protein expression, and thus decreased the levels of both lactate acid and ATP productions. The mechanistic study revealed that cryptolepine could effectively suppress the process of HIF-1α mRNA translation rather than transcription, which was attributed to the inhibition on the phosphorylation of eIF4E regulated by both MAPK and mTOR signaling pathways. Collectively, current findings suggested that cryptolepine possesses the potential to treat breast cancers by modulating HIF-1 both in vitro and in vivo.


Assuntos
Adenocarcinoma , Neoplasias da Mama , Trifosfato de Adenosina/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Feminino , Glicólise , Humanos , Hipóxia/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Alcaloides Indólicos , Quinolinas
6.
Bioorg Chem ; 109: 104740, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33626453

RESUMO

Six new non-classical cardenolides (1-6), and seventeen known ones (7-23) were isolated from Calotropis gigantea. All cardenolides showed inhibitory effect on hypoxia inducible factor-1 (HIF-1) transcriptional activity with IC50 of 8.85 nM-16.69 µM except 5 and 7. The novel 19-dihydrocalotoxin (1) exhibited a comparable HIF-1 inhibitory activity (IC50 of 139.57 nM) to digoxin (IC50 of 145.77 nM), a well-studied HIF-1 inhibitor, and 11, 12, 14, 16 and 19 presented 1.4-15.4 folds stronger HIF-1 inhibition than digoxin. 1 and 11 showed a dose-dependent inhibition on HIF-1α protein, which led to their HIF-1 suppressing effects. Compared with LO2 and H9c2 normal cell lines, both 1 and 11 showed selective cytotoxicity against various cancer cell lines including HCT116, HeLa, HepG2, A549, MCF-7, A2780 and MDA-MB-231. Moreover, a comprehensive structure-activity relationship was concluded for these non-classical cardenolides as HIF-1 inhibitors, which may shed some light on the rational design and development of cardenolide-based anticancer drugs.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Calotropis/química , Cardenolídeos/farmacologia , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Cardenolídeos/química , Cardenolídeos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade
7.
Biomed Pharmacother ; 129: 110462, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32768952

RESUMO

Triple-negative breast cancer (TNBC) is a highly lethal subtype of breast cancer associated with early relapse and metastasis. Epithelial to mesenchymal transition (EMT) plays pivotal roles in the progression of TNBC, including inducing cancer stem cell (CSC) properties, chemoresistance, tumor metastasis, and recurrence. Abnormally activated YAP/TAZ induces EMT in TNBC, making it a promising target for drug development. Our goal is to identify potential YAP/TAZ inhibitors from naturally derivative molecules and further study its effects on inhibiting EMT and metastasis of TNBC. In the current study, we demonstrate that luteolin significantly inhibits YAP/TAZ activity by promoting YAP/TAZ degradation in TNBC cells. Luteolin treatment leads to a decrease of mesenchymal markers and an increase of epithelial markers in both TNBC cells and TAZ-induced mesenchymal cells. Consistently, luteolin treatment inhibits cell migration in TNBC cells. Additionally, luteolin inhibits tumor growth in mice xenografted with TNBC cells. Collectively, our results support luteolin as a novel YAP/TAZ inhibitor for development as a new agent for the treatment of TNBC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Luteolina/farmacologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Proteólise , Transdução de Sinais , Transativadores/genética , Fatores de Transcrição/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/efeitos dos fármacos , Proteínas de Sinalização YAP
8.
J Orthop Translat ; 22: 92-100, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32440504

RESUMO

BACKGROUND: Angiogenesis plays an important role in the development of rheumatoid arthritis (RA), which increases the supply of nutrients, cytokines, and inflammatory cells to the synovial membrane. Genistein (GEN), a soy-derived isoflavone, has been validated that can effectively inhibit the angiogenesis of several tumours. We thus carried out a study in vitro to investigate the effect of GEN in vascular endothelial growth factor (VEGF) expression and angiogenesis induced by the inflammatory environment of RA. METHODS: MH7A cells were used to verify whether GEN can inhibit the expression of VEGF in MH7A cells under inflammatory conditions and demonstrate the mechanism. EA.hy926 â€‹cells were used to verify whether GEN can inhibit the migration and tube formation of vascular endothelial cells in inflammatory environment. RESULTS: GEN dose-dependently inhibited the expression and secretion of interleukin (IL)-6 and VEGF, as well as the nucleus translocation of Signal transducer and activator of transcription 3 (STAT3) in MH7A. Furthermore, GEN inhibited IL-6-induced vascular endothelial cell migration and tube formation in vitro. CONCLUSION: GEN inhibits IL-6-induced VEGF expression and angiogenesis partially through the Janus kinase 2 (JAK2)/STAT3 pathway in RA, which has provided a novel insight into the antiangiogenic activity of GEN in RA. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Our study provides scientific guidance for the clinical translational research of GEN in the RA treatment.

9.
Biomed Pharmacother ; 115: 108860, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31055235

RESUMO

EGFR tyrosine kinase inhibitors (EGFR-TKIs) improve the progression-free survival of patients with non-small cell lung cancer (NSCLC). However, most patients inevitably developed drug resistance. EGFR T790 M mutation is the major mechanism for resistance to EGFR-TKIs and becomes an obstacle for the treatment of NSCLC patients with EGFR activating mutations. Besides, YAP/TAZ also confers resistance to EGFR-TKIs. Our previous study identified gossypol as a YAP/TAZ inhibitor. In the current study, we found that gossypol inhibited cell growth and induced apoptosis in H1975 cells harboring EGFRL858R/T790M. Also, gossypol treatment sensitized H1975 cells to EGFR-TKIs. Our mechanism studies showed that gossypol decreased the protein level of YAP/TAZ, which was abrogated by the proteasome inhibition. Moreover, over-expression of YAP/TAZ reversed the effects of gossypol on H1975 cells, and YAP/TAZ knockdown sensitized H1975 cells to gossypol treatment. Furthermore, gossypol reduced the protein level of EGFRL858R/T790M and inhibited the downstream ERK1/2 pathway in H1975 cells. Our findings suggested that gossypol might serve a promise drug candidate for overcoming EGFR-TKIs resistance by targeting both YAP/TAZ and EGFRL858R/T790M.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Anticoncepcionais Masculinos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Gossipol/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Fatores de Transcrição/metabolismo , Aciltransferases , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Camundongos Nus , Mutação , Proteínas de Sinalização YAP
10.
Cell Death Discov ; 4: 105, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30479839

RESUMO

Triple-negative breast cancer (TNBC) remains a clinical challenge because of the absence of effective therapeutic targets. In TNBC, overexpression of YAP and TAZ correlates with bioactivities of cancer stem cells (CSCs), high histological grade, resistance to chemotherapy, and metastasis. Thus, YAP/TAZ may serve as potential therapeutic targets in TNBC. To identify YAP/TAZ inhibitors, in previous experiments, we screened a library of natural compounds by using YAP/TAZ luciferase reporter assay and identified apigenin as a potential inhibitor. In this study, we demonstrated that apigenin significantly suppressed the proliferation and migration of TNBC cells. Furthermore, we demonstrated that apigenin inhibited stemness features of TNBC cells in both in vitro and in vivo assays. Our mechanism study demonstrated that apigenin decreased YAP/TAZ activity and the expression of target genes, such as CTGF and CYR61, in TNBC cells. We also showed that apigenin disrupted the YAP/TAZ-TEADs protein-protein interaction and decreased expression of TAZ sensitized TNBC cells to apigenin treatment. Collectively, our studies suggest that apigenin is a promising therapeutic agent for the treatment of TNBC patients with high YAP/TAZ activity.

11.
Chem Biol Drug Des ; 92(5): 1851-1858, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29931766

RESUMO

Lung cancer is the number one cancer in terms of both mortality and incidence. Cancer cells differ from normal cells in that they can reprogram their metabolism to support a rapid proliferation rate and alter oxidative phosphorylation processes toward lactic acid fermentation, even under aerobic conditions. Therefore, we aimed to identify new compounds that might act as pyruvate kinase M2 isoform (PKM2) activators and to investigate their anti-cancer efficacy in non-small-cell lung cancer (NSCLC) cells. The molecular docking method was applied to screen PKM2 activators from our virtual natural products library. Then, compounds with promising docking scores were examined for cytotoxic effects in a panel of NSCLC cells using the MTT assay. Functional effects and therapeutic mechanisms were investigated by in vitro enzyme assays, western blotting (WB), and flow cytometry. Molecular docking showed that 0089-0022 acts as a potential PKM2 activator by binding to the kinase pocket. An in vitro enzyme activity assay showed that 0089-0022 is a direct PKM2 activator and that it effectively induces apoptosis in A549 and H1975 cells through inhibition of AKT phosphorylation. Our results suggest that 0089-0022 activates PKM2 and thus is a promising anti-cancer therapeutic candidate in NSCLC.


Assuntos
Antineoplásicos/química , Piruvato Quinase/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Sítios de Ligação , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Isoenzimas/química , Isoenzimas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Piruvato Quinase/metabolismo , Sulfonamidas/química , Sulfonamidas/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
12.
J Nat Prod ; 81(6): 1333-1342, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29883114

RESUMO

Seven new α,ß-diphenyl-γ-butyrolactones (1-7), three new lignans (8-10), five new neolignans (11-15), two new 1,3-biphenylpropanoids (16 and 17), and a new flavonol galactoside-lignan ester (18), together with 43 known compounds (19-61), were isolated from the twigs of Cinnamomum cassia. Their structures were elucidated by spectroscopic data analysis as well as chemical methods. The α,ß-diphenyl-γ-butyrolactones are a class of unique natural compounds that have only been isolated from C. cassia. Compounds 11 and 12 are rare examples of neolignans possessing a 1,2-dioxetane moiety. Compound 13 is a new oxyneolignan possessing a unique C-9-O-C-9' linkage between the benzopyran and cinnamyl alcohol moieties. Compound 15 is the first example of a natural neolignan possessing a 2-styryl-3-phenyltetrahydrofuran skeleton. The isolated compounds were evaluated for their neuroprotective activities against tunicamycin-induced cytotoxicity in SH-SY5Y cells. Compounds 3, 5, 10, 11, 12, 20, 36, and 56 showed statistically significant neuroprotective activity with EC50 values ranging between 21 and 75 µM.


Assuntos
Cinnamomum aromaticum/química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fenóis/química , Casca de Planta/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/farmacologia , Humanos , Lignanas/química
13.
J Org Chem ; 83(4): 2376-2381, 2018 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-29345463

RESUMO

(±)-Sativamides A (1) and B (2), two pairs of nor-lignanamide enantiomers featuring a unique benzo-angular triquinane skeleton, were isolated from the fruits of Cannabis sativa (hemp seed). Their structures were elucidated by detailed spectroscopic analysis and ECD calculations. The resolution of (+)- and (-)-sativamides A and B were achieved by chiral HPLC. Pretreatment of neuroblastoma cells with 1 and 2 significantly reduced the endoplasmic reticulum (ER) stress-induced cytotoxicity.


Assuntos
Cannabis/química , Frutas/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Humanos , Conformação Molecular , Células PC12 , Teoria Quântica , Ratos , Relação Estrutura-Atividade
14.
Fitoterapia ; 124: 73-79, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29074226

RESUMO

Four new monoterpenoid indole alkaloids (MIAs), scholarisines P-S (1-4), and 14 known MIAs (5-18) were isolated from the leaves of Alstonia scholaris (L) R. Br. (Apocynaceae). Their structures were elucidated by analyzing their HRESIMS data and NMR spectroscopic data. All of the isolated MIAs were evaluated for their Nuclear Factor-kappa B (NF-κB) inhibitory activity in HepG2-NF-κB-Luc cells. Among them, five compounds (4, 7, 8, 13 and 16) exhibited significant NF-κB inhibitory activity.


Assuntos
Alstonia/química , NF-kappa B/antagonistas & inibidores , Folhas de Planta/química , Alcaloides de Triptamina e Secologanina/química , Células Hep G2 , Humanos , Estrutura Molecular
15.
Int J Mol Sci ; 18(1)2017 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-28098763

RESUMO

Eleven new abietane type (1‒11), and one new kaurane (12), diterpenes, together with eleven known compounds (13-23), were isolated and identified from the stems of Tripterygium regelii, which has been used as a traditional folk Chinese medicine for the treatment of rheumatoid arthritis in China. The structures of new compounds were characterized by means of the interpretation of high-resolution electrospray ionization mass spectrometry (HRESIMS), extensive nuclear magnetic resonance (NMR) spectroscopic data and comparisons of their experimental CD spectra with calculated electronic circular dichroism (ECD) spectra. Compound 1 is the first abietane type diterpene with an 18→1 lactone ring. Compound 19 was isolated from the plants of the Tripterygium genus for the first time, and compounds 14-17 were isolated from T. regelii for the first time. Triregelin I (9) showed significant cytotoxicity against A2780 and HepG2 with IC50 values of 5.88 and 11.74 µM, respectively. It was found that this compound was inactive against MCF-7 cells. The discovery of these twelve new diterpenes not only provided information on chemical substances of T. regelii, but also contributed to the chemical diversity of natural terpenoids.


Assuntos
Abietanos/isolamento & purificação , Diterpenos do Tipo Caurano/isolamento & purificação , Caules de Planta/química , Tripterygium/química , Abietanos/química , Abietanos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dicroísmo Circular , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Humanos , Espectroscopia de Prótons por Ressonância Magnética
16.
J Ethnopharmacol ; 194: 930-936, 2016 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-27793783

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Calotropis gigantea (L.) Dryand (Apocynaceae) is a medicinal plant native to southern China, India and Southeast Asia. It has been traditionally used for the treatment of several diseases including cancers in these countries. AIM OF THE STUDY: This study aimed to isolate bioactive cardenolides from C. gigantea, to screen their hypoxia-inducible factor (HIF-) 1 inhibitory activity, and to analyze the structure-activity relationship (SAR). MATERIALS AND METHODS: Isolation and purification of cardenolides from the latex and the fruits of C. gigantea were performed by using a series of separation techniques. Their structures were fully characterized by elucidating their NMR and HRMS data. The HIF-1 inhibitory activities of cardenolides were evaluated by using a T47D cell-based dual-luciferase reporter assay. The potent cardenolides were selected to further evaluate their dose-response manner. Cytotoxic effects of selected cardenolides were also examined against breast cancer cell line (MCF-7) and normal mammary epithelial cell line (MCF-10A) by MTT assay. RESULTS: Among twenty isolated cardenolides, compounds 1, 3, 4, 6-8, 14 and 17 exhibited stronger HIF-1 inhibitory activities than that of digoxin, a well-known HIF-1 inhibitor (P<0.001). These eight cardenolides inhibited HIF-1 transcriptional activity in a dose-dependent manner with IC50 values in nanomolar potency (21.8-64.9nM). An analysis of SAR revealed the great contributions of a ß-configuration of the substituents at positions of C-2' and C-3', an aldehydic moiety on C-19, and the dioxane moiety between the aglycone and sugar parts of cardenolides to the HIF-1 inhibitory activity. In contrast, a hydroxyl group at any positions of C-15, C-16 and C-4' of cardenolides showed negative effects on suppressing HIF-1 transcriptional activity. In addition, these eight cardenolides also exhibited potent cytotoxic effects against human breast cancer cell MCF-7 (IC50 values ranged from 30.5 to 68.8nM), but less toxic effects to human normal mammary epithelial cell MCF-10A (IC50 values >20µM). CONCLUSIONS: This is the first report of a comprehensive study of SAR on cardenolides from C. gigantea as HIF-1 inhibitors. Eight cardenolides (1, 3, 4, 6-8, 14 and 17) showed both potent HIF-1 inhibitory activity and strong cytotoxic effect against MCF-7 cancer cells in nanomolar level. The findings of these cardenolides provided important insights into the development of these potent HIF-1 inhibitors as anticancer drug.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Calotropis/química , Cardenolídeos/farmacologia , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Transcrição Gênica/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Látex/química , Células MCF-7 , Estrutura Molecular , Plantas Medicinais/química , Relação Estrutura-Atividade
17.
Fitoterapia ; 113: 69-73, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27425447

RESUMO

Three new triterpenoids, triregelolides A, B (1, 2), and triregeloic acid (3), were isolated from the stems of Tripterygium regelii along with twenty known triterpene analogues (4-23). The structures of three new compounds were identified by analyzing their NMR spectroscopic and HRESIMS data. Compounds 4, 7, 8, 10, 13, 14, 17, 21-23 were isolated from T. regelii for the first time. Compounds 3, 5, 6, 8, 9, 10, 14 and 16 showed inhibitory effects on the proliferation of human breast cancer cells MCF-7 by 24.1%, 69.6%, 72.8%, 21.6%, 23.1%, 43.3%, 25.5% and 23.5% (p<0.05) at a concentration of 10µM, respectively.


Assuntos
Caules de Planta/química , Tripterygium/química , Triterpenos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Extratos Vegetais/química , Triterpenos/isolamento & purificação
18.
Fitoterapia ; 112: 1-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27113553

RESUMO

Twelve new dihydro-ß-agarofuran polyesters, triptregelines A-J (1-3 and 5-11) and triptregelols A, B (4, 12), together with five known ones (13-17) were isolated from the stems of Tripterygium regelii. The structures were determined on the basis of extensive analysis of spectroscopic data (1D, 2D NMR, and UV etc.) and HRMS data. Cytotoxic effects of these compounds were evaluated against a pair of cancer cell lines, A549 and taxol-resistant A549T. Triptofordin B (14) showed cytotoxicity against both A549 and A549T cells with IC50 value of 21.2 and 10.8µM, respectively. In addition, triptregeline B (2), triptregeline C (3), triptregeline H (9) and 1α, 6ß, 15-triacetoxy-8α-benzoyloxy-4ß-hydroxy-9α-(3-nicotinoyloxy)-dihydro-ß-agarofuran (17) exhibited weak cytotoxic effects on taxol-resistant A549T with IC50 values ranged from 29.4 to 54.4µM. The cytotoxic effect of triptofordin B (14) was much less than taxol with IC50 value of 0.08µM on A549 cancer cell.


Assuntos
Antineoplásicos Fitogênicos/química , Poliésteres/química , Sesquiterpenos/química , Tripterygium/química , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Humanos , Estrutura Molecular , Extratos Vegetais/química , Caules de Planta/química , Poliésteres/isolamento & purificação , Sesquiterpenos/isolamento & purificação
19.
J Ethnopharmacol ; 172: 44-60, 2015 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-26113182

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Saussurea involucrata Matsum. & Koidz. is an endangered species of the Asteraceae family, growing in the high mountains of central Asia. It has been, and is, widely used in traditional Uyghur, Mongolian and Kazakhstan medicine as well as in Traditional Chinese Medicine as Tianshan Snow Lotus (Chinese: ). In traditional medical theory, S. involucrata can promote blood circulation, thereby alleviating all symptoms associated with poor circulation. It also reputedly eliminates cold and dampness from the body, diminishes inflammation, invigorates, and strengthens Yin and Yang. It has long been used to treat rheumatoid arthritis, cough with cold, stomach ache, dysmenorrhea, and altitude sickness in Uyghur and Chinese medicine. AIM OF THE REVIEW: To comprehensively summarize the miscellaneous research that has been done regarding the botany, ethnopharmacology, phytochemistry, biological activity, and toxicology of S. involucrata. METHOD: An extensive review of the literature was carried out. Apart from different electronic databases including SciFinder, Chinese National Knowledge Infrastructure (CNKI), ScienceDirect that were sourced for information, abstracts, full-text articles and books written in English and Chinese, including those traditional records tracing back to the Qing Dynasty. Pharmacopoeia of China and other local herbal records in Uighur, Mongolian and Kazakhstan ethnomedicines were investigated and compared for pertinent information. RESULTS: The phytochemistry of S. involucrata has been comprehensively investigated. More than 70 compounds have been isolated and identified; they include phenylpropanoids, flavonoids, coumarins, lignans, sesquiterpenes, steroids, ceramides, polysaccharides. Scientific studies on the biological activity of S. involucrata are equally numerous. The herb has been shown to have anti-neoplastic, anti-inflammatory, analgesic, anti-oxidative, anti-fatigue, anti-aging, anti-hypoxic, neuroprotective and immunomodulating effects. Many have shown correlations to the traditional clinical applications in Traditional Chinese Medicine and medicines. The possible mechanisms of S. involucrata in treating various cancers are revealed in the article, these include inhibition of cancer cells by affecting their growth, adhesion, migration, aggregation and invasion, inhibition of epidermal growth factor receptor signaling in cancer cells, hindrance of cancer cell proliferation, causing cytotoxicity to cancer cells and promoting expression of tumor suppressor genes. Dosage efficacy is found to be generally concentration- and time-dependent. However, studies on the correlation between particular chemical constituents and specific bioactivities are limited. CONCLUSION: In this review, we have documented the existing traditional uses of S. involucrata and summarized recent research into the phytochemistry and pharmacology of S. involucrata. Many of the traditional uses have been validated by phytochemical and modern pharmacological studies but there are still some areas where the current knowledge could be improved. Although studies have confirmed that S. involucrata has a broad range of bioactivities, further in-depth studies on the exact bioactive molecules and the mechanism of action are expected. Whether we should use this herb independently or in combination deserves to be clarified. The exact quality control as well as the toxicology studies is necessary to guarantee the stability and safety of the clinic use. The sustainable use of this endangered resource was also addressed. In conclusion, this review was anticipated to highlight the importance of S. involucrata and provides some directions for the future development of this plant.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Saussurea/química , Animais , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Etnofarmacologia , Humanos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacologia
20.
Phytochemistry ; 107: 175-81, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25189120

RESUMO

Eight ring C-seco and ring-intact limonoids, and 25 known limonoids were isolated from the fruits of Melia toosendan (Meliaceae). Their structures were elucidated on the basis of extensive spectroscopic evidence including HRMS, 1D and 2D NMR spectroscopic data. A total of 29 isolated limonoids was evaluated for NF-κB activities. Among them, eight compounds significantly enhanced the TNFα-induced NF-κB luciferase activity at 10µM, while 10 compounds suppressed the NF-κB activation.


Assuntos
Frutas/química , Limoninas/isolamento & purificação , Limoninas/farmacologia , Melia/química , NF-kappa B/efeitos dos fármacos , Células Hep G2 , Hong Kong , Humanos , Limoninas/química , Luciferases/metabolismo , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fator de Necrose Tumoral alfa/farmacologia
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