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1.
Bioorg Chem ; 108: 104664, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33550071

RESUMO

Hyperlipidemia is the clinical condition where blood has an increased level of lipids, such as cholesterol and triglycerides. Therefore controlling hyperlipidemia is considered to be a protective strategy to treat many associated diseases. Thus, a novel natural product derived pyrrole, and pyrazole-(E)-Labda-8(17),12-diene-15,16-dial conjugates with cholesterol and triglycerides synthesis inhibition potential was designed through scaffold hopping approach and synthesized via one-pot selective cycloaddition. Amongst the tested hybrids, 3i exhibited excellent activity against triglyceride and cholesterol synthesis with the percentage inhibition of 71.73 ± 0.78 and 68.61 ± 1.19, which is comparable to the positive controls fenofibrate and atorvastatin, respectively. Compounds 3j and 3k also exhibited the considerable potential of promising leads. The HMG CoA reductase inhibitory activity of the compounds was consistent with that of inhibitory activity of cholesterol synthesis. Compound 3i showed the highest inhibitory potential (78.61 ± 2.80) percentage of suppression, which was comparable to that of the positive control pravastatin (78.05 ± 5.4). Favourably, none of the compounds showed cytotoxicity (HepG2) in the concentration ranging from 0.5 to 100 µM.


Assuntos
Anticolesterolemiantes/farmacologia , Produtos Biológicos/farmacologia , Diterpenos/farmacologia , Hiperlipidemias/tratamento farmacológico , Pirróis/farmacologia , Triglicerídeos/antagonistas & inibidores , Anticolesterolemiantes/síntese química , Anticolesterolemiantes/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Colesterol/biossíntese , Diterpenos/química , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Hiperlipidemias/metabolismo , Estrutura Molecular , Pirróis/química , Relação Estrutura-Atividade , Triglicerídeos/biossíntese , Células Tumorais Cultivadas
2.
Apoptosis ; 25(9-10): 763-782, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32894380

RESUMO

The head and neck squamous cell carcinoma (HNSCC) constitute about 90% of all head and neck cancers. HNSCC falls in the top 10 cancers in men globally. Epoxyazadiradione (EPA) and Azadiradione (AZA) are the limonoids derived from the medicinal plant Azadirachta indica (popularly known as Neem). Whether or not the limonoids exhibit activities against HNSCC and the associated mechanism remains elusive. Herein, we demonstrate that EPA exhibits stronger activity in HNSCC in comparison to AZA. The limonoids obeyed the Lipinski's rule of 5. EPA exhibited activities in a variety of HNSCC lines like suppression of the proliferation and the induction of apoptosis. The limonoid suppressed the level of proteins associated with anti-apoptosis (survivin, Bcl-2, Bcl-xL), proliferation (cyclin D1), and invasion (MMP-9). Further, the expression of proapoptotic Bax and caspase-9 cleavage was induced by the limonoid. Exposure of EPA induced reactive oxygen species (ROS) generation in the FaDu cells. N-acetyl-L-cysteine (ROS scavenger) abrogated the down-regulation of tumorigenic proteins caused by EPA exposure. EPA induced NOX-5 while suppressing the expression of programmed death-ligand 1 (PD-L1). Further, hydrogen peroxide induced NF-κB-p65 nuclear translocation and EPA inhibited the translocation. Finally, EPA modulated the expression of lncRNAs in HNSCC lines. Overall, these results have shown that EPA exhibit activities against HNSCC by targeting multiple cancer related signalling molecules. Currently, we are evaluating the efficacy of this molecule in mice models.


Assuntos
Antígeno B7-H1/genética , Limoninas/farmacologia , NADPH Oxidase 5/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Fator de Transcrição RelA/genética , Animais , Apoptose/efeitos dos fármacos , Azadirachta/química , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metaloproteinase 9 da Matriz/genética , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Survivina/genética
3.
Phytother Res ; 31(12): 1892-1902, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29044755

RESUMO

Epoxyazadiradione (EAD) is an important limonoid present in Neem (Azadirachta indica) plant. In the present study, we have purified EAD from Neem seed and studied its anticancer potential in human cervical cancer (HeLa) cells. Cell proliferation inhibition studies indicated that the GI50 value of EAD is 7.5 ± 0.0092 µM in HeLa cells, whereas up to 50 µM concentrations EAD did not affect the growth of normal H9C2 cells. The control drug cisplatin inhibited the growth of both HeLa and H9C2 cells with a GI50 value of 2.92 ± 1.192 and 4.22 ± 1.568 µM, respectively. Nuclear DNA fragmentation, cell membrane blebbing, phosphatidylserine translocation, upregulation of Bax, caspase 3 activity and poly (ADP ribose) polymerase cleavage and downregulation of BCl2 in HeLa cells on treatment with EAD indicated the apoptotic cell death. Increase in caspase 9 activity and release of active cytochrome c to the cytoplasm on treatment with EAD confirmed that the apoptosis was mediated through the mitochondrial pathway. Epoxyazadiradione also inhibited the nuclear translocation of nuclear factor κB in HeLa cells. Thus, our studies demonstrated EAD as a potent and safe chemotherapeutic agent when compared with the standard drug cisplatin that is toxic to both cancer and normal cells equally. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Apoptose/efeitos dos fármacos , Azadirachta/química , Limoninas/química , Mitocôndrias/efeitos dos fármacos , Neoplasias do Colo do Útero/tratamento farmacológico , Feminino , Células HeLa , Humanos , Limoninas/uso terapêutico , NF-kappa B/metabolismo , Sementes , Neoplasias do Colo do Útero/patologia
4.
Bioorg Med Chem Lett ; 26(7): 1767-71, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26916436

RESUMO

(-)-Cubebin, isolated from the seeds of Piper cubeba, and its five different types of derivatives (a total of 17), with varying functionalities, were tested for their in vitro anticancer activity against six human cancer cell lines (A549, K562, SiHa, KB, HCT116 and HT29) using MTT assay. Cubebin as well as its derivatives containing lactone and amide groups showed significant anticancer activity. In some of the tested cell lines, the amide derivatives showed higher activity. Morphological analysis indicated that these compounds act through apoptosis mediated pathway of cell death and we expect that these results will pave new paths in the development of novel anticancer agents by the derivatization of (-)-cubebin.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Lignanas/química , Lignanas/farmacologia , Piper/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Lignanas/isolamento & purificação , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Sementes/química
5.
J Biol Chem ; 288(45): 32343-32356, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24078627

RESUMO

Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has shown efficacy in a phase 2 clinical trial, development of resistance to TRAIL by tumor cells is a major roadblock. We investigated whether azadirone, a limonoidal tetranortriterpene, can sensitize human tumor cells to TRAIL. Results indicate that azadirone sensitized cancer cells to TRAIL. The limonoid induced expression of death receptor (DR) 5 and DR4 but did not affect expression of decoy receptors in cancer cells. The induction of DRs was mediated through activation of ERK and through up-regulation of a transcription factor CCAAT enhancer-binding protein homologous protein (CHOP) as silencing of these signaling molecules abrogated the effect of azadirone. These effects of azadirone were cancer cell-specific. The CHOP binding site on the DR5 gene was required for induction of DR5 by azadirone. Up-regulation of DRs was mediated through the generation of reactive oxygen species (ROS) as ROS scavengers reduced the effect of azadirone on ERK activation, CHOP up-regulation, DR induction, and TRAIL sensitization. The induction of DRs by this limonoid was independent of p53, but sensitization to TRAIL was p53-dependent. The limonoid down-regulated the expression of cell survival proteins and up-regulated the proapoptotic proteins. The combination of azadirone with TRAIL was found to be additive at concentrations lower than IC50, whereas at higher concentrations, the combination was synergistic. Overall, this study indicates that azadirone can sensitize cancer cells to TRAIL through ROS-ERK-CHOP-mediated up-regulation of DR5 and DR4 signaling, down-regulation of cell survival proteins, and up-regulation of proapoptotic proteins.


Assuntos
Antineoplásicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Limoninas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Elementos de Resposta , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Fator de Transcrição CHOP/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Reguladoras de Apoptose/biossíntese , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Fator de Transcrição CHOP/genética , Proteína Supressora de Tumor p53/genética , Regulação para Cima/efeitos dos fármacos
6.
J Biol Chem ; 286(2): 1134-46, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21078664

RESUMO

TNF-related apoptosis-inducing ligand (TRAIL) shows promise as a cancer treatment, but acquired tumor resistance to TRAIL is a roadblock. Here we investigated whether nimbolide, a limonoid, could sensitize human colon cancer cells to TRAIL. As indicated by assays that measure esterase activity, sub-G(1) fractions, mitochondrial activity, and activation of caspases, nimbolide potentiated the effect of TRAIL. This limonoid also enhanced expression of death receptors (DRs) DR5 and DR4 in cancer cells. Gene silencing of the receptors reduced the effect of limonoid on TRAIL-induced apoptosis. Using pharmacological inhibitors, we found that activation of ERK and p38 MAPK was required for DR up-regulation by nimbolide. Gene silencing of ERK abolished the enhancement of TRAIL-induced apoptosis. Moreover, our studies indicate that the limonoid induced reactive oxygen species production, which was required for ERK activation, up-regulation of DRs, and sensitization to TRAIL; these effects were mimicked by H(2)O(2). In addition, nimbolide down-regulated cell survival proteins, including I-FLICE, cIAP-1, cIAP-2, Bcl-2, Bcl-xL, survivin, and X-linked inhibitor of apoptosis protein, and up-regulated the pro-apoptotic proteins p53 and Bax. Interestingly, p53 and Bax up-regulation by nimbolide was required for sensitization to TRAIL but not for DR up-regulation. Overall, our results indicate that nimbolide can sensitize colon cancer cells to TRAIL-induced apoptosis through three distinct mechanisms: reactive oxygen species- and ERK-mediated up-regulation of DR5 and DR4, down-regulation of cell survival proteins, and up-regulation of p53 and Bax.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Limoninas/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Neoplasias da Mama , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Células HCT116 , Células HT29 , Humanos , Neoplasias Renais , Leucemia Mielogênica Crônica BCR-ABL Positiva , Neoplasias Pulmonares , Mieloma Múltiplo , Neoplasias Pancreáticas , Espécies Reativas de Oxigênio/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
9.
Mol Carcinog ; 51(6): 475-90, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21678498

RESUMO

Nimbolide, a plant-derived limonoid has been shown to exert its antiproliferative effects in various cell lines. We demonstrate that nimbolide effectively inhibited proliferation of WiDr colon cancer cells through inhibition of cyclin A leading to S phase arrest. It also caused activation of caspase-mediated apoptosis through the inhibition of ERK1/2 and activation of p38 and JNK1/2. Further nimbolide effectively retarded tumor cell migration and invasion through inhibition of metalloproteinase-2/9 (MMP-2/9) expression, both at the mRNA and protein level. It was also a strong inhibitor of VEGF expression, promoter activity, and in vitro angiogenesis. Finally, nimbolide suppressed the nuclear translocation of p65/p50 and DNA binding of NF-κB, which is an important transcription factor for controlling MMP-2/9 and VEGF gene expression.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/genética , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Limoninas/farmacologia , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , NF-kappa B/metabolismo , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/enzimologia , Neoplasias do Colo/metabolismo , Ciclina A/antagonistas & inibidores , Ciclina D1/antagonistas & inibidores , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Limoninas/química , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Invasividade Neoplásica , Neovascularização Patológica , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
J Biomed Biotechnol ; 2012: 721285, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22500104

RESUMO

This study was designed to isolate the compounds responsible for the cytotoxic properties of South Indian Elephantopus scaber L. and further investigate their effects on quiescent and proliferating cells. Bioassay-guided isolation of the whole plant of chloroform extract of South Indian Elephantopus scaber afforded the known sesquiterpene lactone, deoxyelephantopin, and isodeoxyelephantopin whose structures were determined by spectroscopic methods. These compounds caused a dose dependent reduction in the viability of L-929 tumour cells in 72 h culture (IC(50) value of 2.7 µg/mL and 3.3 µg/mL) by the cell viability assay. Both the compounds act selectively on quiescent and PHA-stimulated proliferating human lymphocytes and inhibited tritiated thymidine incorporation into cellular DNA of DLA tumour cells. The compound deoxyelephantopin at a concentration of 3 µg/mL caused maximum apoptotic cells. It also exhibited significant in vivo antitumour efficacy against DLA tumour cells. The results, therefore, indicate that the antiproliferative property of deoxyelephantopin and isodeoxyelephantopin could be used in regimens for treating tumors with extensive proliferative potencies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Asteraceae/química , Lactonas/farmacologia , Linfócitos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , DNA/metabolismo , Relação Dose-Resposta a Droga , Células HCT116 , Humanos , Lactonas/química , Lactonas/isolamento & purificação , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/imunologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Análise de Sobrevida
11.
Nat Prod Res ; 36(10): 2599-2603, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35635050

RESUMO

Nine non-alkaloid constituents viz., sitostenone (1), ß-sitosterol (2), naringenin (3), aromadendrin (4), matairesinol (5), vanillic acid (6), ferulic acid (7), protocatechuic acid (8) and sitosterol-3-O-ß-D-glucopyranoside (9) were isolated from the acetone extract as well as five alkaloids viz., japindine (10), sarcorucinine D (11), dictyophlebin (12), chonemorphine (13) and N-formylchonemorphine (14) were isolated from the ethanol extract of Chonemorpha fragrans roots. Except ß-sitosterol, all other non-alkaloid compounds and the alkaloid sarcorucinine D are being reported for the first time from C. fragrans. From the MIC and MBC values, it has been found that sarcorucinine D shows most promising antibacterial activity. Quantification of antibacterial activity as well as killing curve determinations were performed in order to confirm the efficacy of the compound. The cytotoxic activity studies revealed that it is nontoxic up to 100 µM concentration.


Assuntos
Apocynaceae , Medicamentos de Ervas Chinesas , Antibacterianos/análise , Antibacterianos/farmacologia , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química
12.
Mol Pharmacol ; 80(5): 769-81, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21795584

RESUMO

Although inflammatory pathways have been linked with various chronic diseases including cancer, identification of an agent that can suppress these pathways has therapeutic potential. Herein we describe the identification of a novel compound bharangin, a diterpenoid quinonemethide that can suppress pro-inflammatory pathways specifically. We found that bharangin suppresses nuclear factor (NF)-κB activation induced by pro-inflammatory cytokine, tumor promoter, cigarette smoke, and endotoxin. Inhibition of NF-κB activation was mediated through the suppression of phosphorylation and degradation of inhibitor of nuclear factor-κB (IκBα); inhibition of IκBα kinase activation; and suppression of p65 nuclear translocation, and phosphorylation. The diterpenoid inhibited binding of p65 to DNA. A reducing agent reversed the inhibitory effect, and mutation of the Cys(38) of p65 to serine abrogated the effect of bharangin on p65-DNA binding. Molecular docking revealed strong interaction of the ligand with the p65 via two hydrogen bonds one with Lys(37) (2.204 Å) and another with Cys(38) (2.023 Å). The inhibitory effect of bharangin on NF-κB activation was specific, inasmuch as binding of activator protein-1 and octameric transcription factor 1 to DNA was not affected. Suppression of NF-κB activation by this diterpenoid caused the down-regulation of the expression of proteins involved in tumor cell survival, proliferation, invasion, and angiogenesis, leading to potentiation of apoptosis, suppression of proliferation, and invasion of tumor cells. Furthermore, the genetic deletion of p65 and mutation of p65Cys(38) residue to Ser abolished the affect of bharangin. Overall, our results demonstrate that bharangin specifically inhibits the NF-κB activation pathway by modifying p65 and inhibiting IκBα kinase activation and potentiates apoptosis in tumor cells.


Assuntos
Cisteína/metabolismo , Flavonoides/farmacologia , Expressão Gênica/fisiologia , NF-kappa B/metabolismo , Apoptose , Western Blotting , Carcinógenos/farmacologia , Linhagem Celular Tumoral , Ensaio de Desvio de Mobilidade Eletroforética , Genes Reporter , Humanos , Imuno-Histoquímica , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , NF-kappa B/química , NF-kappa B/fisiologia , Fosforilação
13.
J Biol Chem ; 285(35): 26987-27000, 2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-20576605

RESUMO

Crotepoxide (a substituted cyclohexane diepoxide), isolated from Kaempferia pulchra (peacock ginger), although linked to antitumor and anti-inflammatory activities, the mechanism by which it exhibits these activities, is not yet understood. Because nuclear factor kappaB (NF-kappaB) plays a critical role in these signaling pathways, we investigated the effects of crotepoxide on NF-kappaB-mediated cellular responses in human cancer cells. We found that crotepoxide potentiated tumor necrosis factor (TNF), and chemotherapeutic agents induced apoptosis and inhibited the expression of NF-kappaB-regulated gene products involved in anti-apoptosis (Bcl-2, Bcl-xL, IAP1,(2) MCl-1, survivin, and TRAF1), apoptosis (Bax, Bid), inflammation (COX-2), proliferation (cyclin D1 and c-myc), invasion (ICAM-1 and MMP-9), and angiogenesis (VEGF). We also found that crotepoxide inhibited both inducible and constitutive NF-kappaB activation. Crotepoxide inhibition of NF-kappaB was not inducer-specific; it inhibited NF-kappaB activation induced by TNF, phorbol 12-myristate 13-acetate, lipopolysaccharide, and cigarette smoke. Crotepoxide suppression of NF-kappaB was not cell type-specific because NF-kappaB activation was inhibited in myeloid, leukemia, and epithelial cells. Furthermore, we found that crotepoxide inhibited TAK1 activation, which led to suppression of IkappaBalpha kinase, abrogation of IkappaBalpha phosphorylation and degradation, nuclear translocation of p65, and suppression of NF-kappaB-dependent reporter gene expression. Overall, our results indicate that crotepoxide sensitizes tumor cells to cytokines and chemotherapeutic agents through inhibition of NF-kappaB and NF-kappaB-regulated gene products, and this may provide the molecular basis for crotepoxide ability to suppress inflammation and carcinogenesis.


Assuntos
Indutores da Angiogênese/metabolismo , Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Proliferação de Células/efeitos dos fármacos , Compostos de Epóxi/farmacologia , Mediadores da Inflamação/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Humanos , Invasividade Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Zingiberaceae/química
14.
J Biol Chem ; 285(46): 35406-17, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-20829362

RESUMO

Reverse pharmacology, also called the "bedside to bench" approach, that deals with new uses for a well known molecular entity has been used extensively in cancer drug development to identify novel compounds and delineate their mechanisms of action. Here, we show that nimbolide, a triterpenoid isolated from Azadirachta indica, enhanced the apoptosis induced by inflammatory cytokines and chemotherapeutic agents in tumor cells. This limonoid abrogated the expression of proteins associated with cell survival (Bcl-2, Bcl-xL, IAP-1, and IAP-2), proliferation (cyclin D1), invasion (MMP-9), and angiogenesis (VEGF), all regulated by nuclear factor (NF)-κB. Nimbolide inhibited the activation of NF-κB induced by carcinogens and inflammatory stimuli. Constitutively active NF-κB found in most tumor cells was also inhibited. We found that suppression of NF-κB activation by nimbolide was caused by inhibition of IκB kinase (IKK), which led to suppression of IκBα phosphorylation and degradation, nuclear translocation, DNA binding, and gene transcription. Reducing agent reversed the action of the limonoid, suggesting the involvement of a cysteine residue. Replacement of Cys(179) of IKK-ß with alanine abolished the effect of nimbolide, suggesting that Cys(179) plays a critical role in inhibiting the NF-κB activation. Overall, our results indicate that nimbolide can sensitize tumor cells to chemotherapeutic agents through interaction with IKK, leading to inhibition of NF-κB-regulated proteins.


Assuntos
Proliferação de Células/efeitos dos fármacos , Quinase I-kappa B/metabolismo , Limoninas/farmacologia , NF-kappa B/metabolismo , Substituição de Aminoácidos , Apoptose/efeitos dos fármacos , Azadirachta/química , Western Blotting , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Cisteína/genética , Cisteína/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Células HEK293 , Células HL-60 , Humanos , Quinase I-kappa B/genética , Células Jurkat , Células K562 , Limoninas/química , Estrutura Molecular , NF-kappa B/genética , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Células U937 , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Mol Cancer Ther ; 7(10): 3306-17, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18852134

RESUMO

Compounds isolated from members of the Zingiberaceae family are traditionally used as a medicine against inflammatory diseases, but little is known about the mechanism. Here, we report the isolation and structural identification of coronarin D [E-labda-8(17),12-diene-15-ol], a labdane-type diterpene, from Hedychium coronarium and delineate its mechanism of action. Because the transcription factor nuclear factor-kappaB (NF-kappaB) is a key mediator of inflammation, apoptosis, invasion, and osteoclastogenesis, we investigated the effect of coronarin D on NF-kappaB activation pathway, NF-kappaB-regulated gene products, and NF-kappaB-regulated cellular responses. The coronarin D inhibited NF-kappaB activation induced by different inflammatory stimuli and carcinogens. This labdane also suppressed constitutive NF-kappaB activity in different cell lines and inhibited IkappaBalpha kinase activation, thus leading to the suppression of IkappaBalpha phosphorylation, degradation, p65 nuclear translocation, and reporter gene transcription. Coronarin D also inhibited the NF-kappaB-regulated gene products involved in cell survival (inhibitor of apoptosis protein 1, Bcl-2, survivin, and tumor necrosis factor receptor-associated factor-2), proliferation (c-myc, cyclin D1, and cyclooxygenase-2), invasion (matrix metalloproteinase-9), and angiogenesis (vascular endothelial growth factor). Suppression of these gene products by the diterpene enhanced apoptosis induced by TNF and chemotherapeutic agents, suppressed TNF-induced cellular invasion, and abrogated receptor activator of NF-kappaB ligand-induced osteoclastogenesis. Coronarin D was found to be more potent than its analogue coronarin D acid. Overall, our results show that coronarin D inhibited NF-kappaB activation pathway, which leads to inhibition of inflammation, invasion, and osteoclastogenesis, as well as potentiation of apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diterpenos/farmacologia , NF-kappa B/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Diterpenos/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Proteínas I-kappa B/metabolismo , Camundongos , Inibidor de NF-kappaB alfa , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ligante RANK/farmacologia , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
16.
Nat Prod Res ; 33(8): 1204-1208, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29607669

RESUMO

Myristica fragrans Houtt., the source of very important spice 'nutmeg' used world over is native to India, Indonesia, Sri Lanka, South Africa and Southeast Asia. Phytochemical investigation of M. fragrans stem bark led to the isolation of bis-aryl dimethyl tetrahydrofuran lignans, such as grandisin [(7S,8S,7'S,8'S)-3,3',4,4',5,5'-hexamethoxy-7,7',8,8'-lignan] and (7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7,7',8,8'-lignan along with important lignans and neolignans, licarinA, licarin B, odoratisol A, (2S, 3R)-7-methoxy-3-methyl-5-((E)-prop-1-enyl)-2-(5-methoxy,3,4-methylenedioxyphenyl)-2,3-dihydrobenzofuran, elemicin, fragransin B1, raphidecursinol B, erythro-(7S,8R)-Δ8'-4,7-dihydroxy-3,5,3'-trimethoxy-8-O-4'-neolignan, erythro-(7S,8R)-Δ8'-7-hydroxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan, surinamensin.and ß-sitosterol. Structures of the 12 compounds isolated were unambiguously identified by various spectroscopic methods. The former two compounds were isolated from M. fragrans for the first time. Furthermore, the X-ray crystal structure of odoratisol A is reported in this paper for the first time.


Assuntos
Myristica/química , Compostos Fitoquímicos/análise , Casca de Planta/química , Anisóis , Benzofuranos , Dioxóis , Furanos/análise , Furanos/isolamento & purificação , Índia , Indonésia , Lignanas/análise , Lignanas/isolamento & purificação , Estrutura Molecular , Análise Espectral , Sri Lanka
18.
Sci Rep ; 9(1): 17980, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784542

RESUMO

The sesquiterpene lactones, Isodeoxyelephantopin (IDET) and Deoxyelephantopin (DET) are known to exhibit activities against some cancer types. The activities of these lactones against breast cancer and the molecular bases is not known. We examined the efficacy of lactones in breast cancer preclinical model. Although both lactones exhibited drug like properties, IDET was relatively effective in comparison to DET. IDET suppressed the proliferation of both invasive and non-invasive breast cancer cell lines. IDET also suppressed the colony formation and migration of breast cancer cells. The assays for Acridine Orange (AO)/Propidium Iodide (PI) staining, cell cycle distribution, phosphatidylserine externalization and DNA laddering suggested the apoptosis inducing potential of IDET. The treatment with IDET also induced an accumulation of cells in the sub-G1 and G2/M phases. The exposure of breast cancer cells to the lactone was associated with a depolarization in mitochondrial membrane potential, and cleavage of caspase and PARP. The lactone induced reactive oxygen species (ROS) generation in breast cancer cells. Further, the use of N-acetyl cysteine (NAC) suppressed IDET induced ROS generation and apoptosis. The NF-κB-p65 nuclear translocation induced by okadaic acid (OA) was suppressed by the sesquiterpene. IDET also suppressed the expression of NF-κB regulated tumorigenic proteins, and induced the expression of proapoptotic gene (Bax) in cancer cells. While the expression of oncogenic lncRNAs was suppressed, the tumor suppressor lncRNAs were induced by the sesquiterpene. Collectively, the modulation of multiple cell signaling molecules by IDET may contribute to its activities in breast cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Asteraceae/química , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/genética , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lactonas/química , Lactonas/uso terapêutico , Potencial da Membrana Mitocondrial/efeitos dos fármacos , RNA Longo não Codificante/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/química , Sesquiterpenos/uso terapêutico , Transdução de Sinais/genética , Estereoisomerismo , Fator de Transcrição RelA/metabolismo
19.
Biochim Biophys Acta Gen Subj ; 1862(12): 2738-2749, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30251663

RESUMO

Breast cancer remains one of the leading causes of cancer related deaths in women worldwide. Bharangin is a diterpenoid quinonemethide that has demonstrated therapeutic potential against leukemia, lymphoma, and multiple myeloma cells. Whether this diterpenoid exhibit activities against breast cancer cells and the underlying mechanism is largely unknown. Herein, we provide evidence that bharangin suppresses the proliferation of MCF-7, MDA-MB-231, MDA-MB-453, MDA-MB-468 and T-47D breast cancer cells. As examined by AO/PI staining, DAPI staining, sub-G1 analysis, phosphatidylserine externalization, caspase activation, DNA laddering, and poly-ADP ribose polymerase cleavage, the diterpenoid induced apoptosis in breast cancer cells. The growth inhibitory effect of bharangin on breast cancer cells was further confirmed from colony-formation assay. Furthermore, the cancer cell migration was also suppressed by the diterpenoid. Mechanistically, bharangin was found to modulate multiple cancer related cell signalling pathways in breast cancer cells. Bharangin suppressed the expression of cell survival and invasive proteins, and induced Bax and mitochondrial depolarization in breast cancer cells. The diterpenoid also suppressed the activation of pro-inflammatory transcription factor, nuclear factor (NF)-κB induced by okadaic acid. Finally, the diterpenoid induced the expression of tumor suppressor lncRNAs (MEG-3, GAS-5), while down-regulating oncogenic H19 expression. Overall, these results suggest that bharangin exhibits anti-carcinogenic, anti-proliferative and anti-inflammatory activities against breast cancer cells. The modulation of lncRNA expression and inhibition of NF-κB activation by bharangin may contribute to its anti-carcinogenic activities.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/patologia , Flavonoides/farmacologia , NF-kappa B/fisiologia , RNA Longo não Codificante/fisiologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Poli(ADP-Ribose) Polimerase-1/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
ACS Med Chem Lett ; 9(7): 662-666, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30034597

RESUMO

Obesity contributes to the genesis of many metabolic disorders including dyslipidemia, coronary heart disease (CHD), nonalcoholic fatty liver, type 2 diabetes, etc. Pancreatic lipase plays a vital role in food fat digestion and absorption. Therefore, to control obesity, inhibition of pancreatic lipase is the active therapy. Thus, novel natural product derived labdane appended triazoles with pancreatic lipase inhibition potential were designed and synthesized. Among these hybrids, 6b and 6f exhibited excellent inhibitory activity (IC50 0.75 ± 0.02 µM and 0.77 ± 0.01 µM), slightly better than that of the positive control Orlistat (IC50 0.8 ± 0.03 µM). Compounds 6c, 6e, and 6g-j inhibited the PL comparable to that of positive control. Interestingly none of the compounds showed cytotoxicity (Hep G2) in the concentration range from 0.5 to 100 µM. Overall results reveal the potential of labdane appended triazoles as antiobesity agents.

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