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1.
Proc Natl Acad Sci U S A ; 119(49): e2209256119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36454752

RESUMO

Auxin inactivation is critical for plant growth and development. To develop plant growth regulators functioning in auxin inactivation pathway, we performed a phenotype-based chemical screen in Arabidopsis and identified a chemical, nalacin, that partially mimicked the effects of auxin. Genetic, pharmacological, and biochemical approaches demonstrated that nalacin exerts its auxin-like activities by inhibiting indole-3-acetic acid (IAA) conjugation that is mediated by Gretchen Hagen 3 (GH3) acyl acid amido synthetases. The crystal structure of Arabidopsis GH3.6 in complex with D4 (a derivative of nalacin) together with docking simulation analysis revealed the molecular basis of the inhibition of group II GH3 by nalacin. Sequence alignment analysis indicated broad bioactivities of nalacin and D4 as inhibitors of GH3s in vascular plants, which were confirmed, at least, in tomato and rice. In summary, our work identifies nalacin as a potent inhibitor of IAA conjugation mediated by group II GH3 that plays versatile roles in hormone-regulated plant development and has potential applications in both basic research and agriculture.


Assuntos
Arabidopsis , Ligases , Arabidopsis/genética , Ácidos Indolacéticos/farmacologia , Fenômenos Químicos , Reguladores de Crescimento de Plantas/farmacologia , Testes Genéticos
2.
New Phytol ; 241(2): 764-778, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37904576

RESUMO

Bioactive triterpenes feature complex fused-ring structures, primarily shaped by the first-committed enzyme, 2,3-oxidosqualene cyclases (OSCs) in plant triterpene biosynthesis. Triterpenes with B,C-ring-opened skeletons are extremely rare with unknown formation mechanisms, harbouring unchartered chemistry and biology. Here, through mining the genome of Chenopodium quinoa followed by functional characterization, we identified a stress-responsive and neofunctionalized OSC capable of generating B,C-ring-opened triterpenes, including camelliol A and B and the novel (-)-quinoxide A as wax components of the specialized epidermal bladder cells, namely the quinoxide synthase (CqQS). Protein structure analysis followed by site-directed mutagenesis identified key variable amino acid sites underlying functional interconversion between pentacyclic ß-amyrin synthase (CqbAS1) and B,C-ring-opened triterpene synthase CqQS. Mutation of one key residue (N612K) in even evolutionarily distant Arabidopsis ß-amyrin synthase could generate quinoxides, indicating a conserved mechanism for B,C-ring-opened triterpene formation in plants. Quantum computation combined with docking experiments further suggests that conformations of conserved W613 and F413 of CqQS might be key to selectively stabilizing intermediate carbocations towards B,C-ring-opened triterpene formation. Our findings shed light on quinoa triterpene skeletal diversity and mechanisms underlying B,C-ring-opened triterpene biosynthesis, opening avenues towards accessing their chemistry and biology and paving the way for quinoa trait engineering and quality improvement.


Assuntos
Chenopodium quinoa , Transferases Intramoleculares , Triterpenos , Chenopodium quinoa/metabolismo , Triterpenos/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo
3.
Nat Chem Biol ; 18(7): 774-781, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761075

RESUMO

Soft-bodied slow-moving sea creatures such as sea stars and sea cucumbers lack an adaptive immune system and have instead evolved the ability to make specialized protective chemicals (glycosylated steroids and triterpenes) as part of their innate immune system. This raises the intriguing question of how these biosynthetic pathways have evolved. Sea star saponins are steroidal, while those of the sea cucumber are triterpenoid. Sterol biosynthesis in animals involves cyclization of 2,3-oxidosqualene to lanosterol by the oxidosqualene cyclase (OSC) enzyme lanosterol synthase (LSS). Here we show that sea cucumbers lack LSS and instead have two divergent OSCs that produce triterpene saponins and that are likely to have evolved from an ancestral LSS by gene duplication and neofunctionalization. We further show that sea cucumbers make alternate sterols that confer protection against self-poisoning by their own saponins. Collectively, these events have enabled sea cucumbers to evolve the ability to produce saponins and saponin-resistant sterols concomitantly.


Assuntos
Saponinas , Pepinos-do-Mar , Triterpenos , Animais , Glicosilação , Esteróis
4.
Environ Toxicol ; 38(10): 2287-2297, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37318315

RESUMO

Metastasis is commonly occurred in gastric cancer, and it is caused and responsible for one of the major cancer-related mortality in gastric cancer patients. Allyl isothiocyanate (AITC), a natural product, exhibits anticancer activities in human many cancer cells, including gastric cancer. However, no available report shows AITC inhibits gastric cancer cell metastasis. Herein, we evaluated the impact of AITC on cell migration and invasion of human gastric cancer AGS cells in vitro. AITC at 5-20 µM did not induce significant cell morphological damages observed by contrast-phase microscopy but decreased cell viability assayed by flow cytometry. After AGS cells were further examined by atomic force microscopy (AFM), which indicated AITC affected cell membrane and morphology in AGS cells. AITC significantly suppressed cell motility examined by scratch wound healing assay. The results of the gelatin zymography assay revealed that AITC significantly suppressed the MMP-2 and MMP-9 activities. In addition, AITC suppressed cell migration and invasion were performed by transwell chamber assays at 24 h in AGS cells. Furthermore, AITC inhibited cell migration and invasion by affecting PI3K/AKT and MAPK signaling pathways in AGS cells. The decreased expressions of p-AKTThr308 , GRB2, and Vimentin in AGS cells also were confirmed by confocal laser microscopy. Our findings suggest that AITC may be an anti-metastasis candidate for human gastric cancer treatment.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias Gástricas , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Gástricas/metabolismo , Transdução de Sinais , Movimento Celular , Linhagem Celular Tumoral , Invasividade Neoplásica , Proliferação de Células
5.
J Integr Plant Biol ; 65(2): 417-443, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35852486

RESUMO

Plant natural products have been extensively exploited in food, medicine, flavor, cosmetic, renewable fuel, and other industrial sectors. Synthetic biology has recently emerged as a promising means for the cost-effective and sustainable production of natural products. Compared with engineering microbes for the production of plant natural products, the potential of plants as chassis for producing these compounds is underestimated, largely due to challenges encountered in engineering plants. Knowledge in plant engineering is instrumental for enabling the effective and efficient production of valuable phytochemicals in plants, and also paves the way for a more sustainable future agriculture. In this manuscript, we briefly recap the biosynthesis of plant natural products, focusing primarily on industrially important terpenoids, alkaloids, and phenylpropanoids. We further summarize the plant hosts and strategies that have been used to engineer the production of natural products. The challenges and opportunities of using plant synthetic biology to achieve rapid and scalable production of high-value plant natural products are also discussed.


Assuntos
Produtos Biológicos , Engenharia Metabólica , Biologia Sintética , Plantas/genética , Terpenos
6.
Nat Prod Rep ; 39(7): 1393-1422, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35766105

RESUMO

Covering: 2015-2022Plants and microbes have coevolved since their appearance, and their interactions, to some extent, define plant health. A reasonable fraction of small molecules plants produced are involved in mediating plant-microbe interactions, yet their functions and biosynthesis remain fragmented. The identification of these compounds and their biosynthetic genes will open up avenues for plant fitness improvement by manipulating metabolite-mediated plant-microbe interactions. Herein, we integrate the current knowledge on their chemical structures, bioactivities, and biosynthesis with the view of providing a high-level overview on their biosynthetic origins and evolutionary trajectory, and pinpointing the yet unknown and key enzymatic steps in diverse biosynthetic pathways. We further discuss the theoretical basis and prospects for directing plant signaling metabolite biosynthesis for microbe-aided plant health improvement in the future.


Assuntos
Plantas , Transdução de Sinais , Evolução Biológica , Plantas/metabolismo
7.
BMC Plant Biol ; 22(1): 237, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538406

RESUMO

BACKGROUND: Quinoa (Chenopodium quinoa), a dicotyledonous species native to Andean region, is an emerging crop worldwide nowadays due to its high nutritional value and resistance to extreme abiotic stresses. Although it is well known that seed germination is an important and multiple physiological process, the network regulation of quinoa seed germination is largely unknown. RESULTS: Here, we performed transcriptomic study in five stages during transition from quinoa dry seed to seedling. Together with the GC-MS based metabolome analysis, we found that seed metabolism is reprogrammed with significant alteration of multiple phytohormones (especially abscisic acid) and other nutrients during the elongation of radicels. Cell-wall remodeling is another main active process happening in the early period of quinoa seed germination. Photosynthesis was fully activated at the final stage, promoting the biosynthesis of amino acids and protein to allow seedling growth. The multi-omics analysis revealed global changes in metabolic pathways and phenotype during quinoa seed germination. CONCLUSION: The transcriptomic and metabolomic landscape depicted here pave ways for further gene function elucidation and quinoa development in the future.


Assuntos
Chenopodium quinoa , Chenopodium quinoa/fisiologia , Germinação/genética , Plântula/genética , Plântula/metabolismo , Sementes , Transcriptoma
8.
New Phytol ; 234(6): 1945-1950, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34877653

RESUMO

Plants and microbes coinhabit the earth and have coevolved during environmental changes over time. Root metabolites are the key to mediating the dynamic association between plants and microbes, yet the underlying functions and mechanisms behind this remain largely illusive. Knowledge of metabolite-mediated alteration of the root microbiota in response to environmental stress will open avenues for engineering root microbiotas for improved plant stress resistance and health. Here, we synthesize recent advances connecting environmental stresses, the root metabolome and microbiota, and propose integrated synthetic biology-based strategies for tuning the plant root metabolome in situ for microbe-assisted stress resistance, offering potential solutions to combat climate change. The current limitations, challenges and perspectives for engineering the plant root metabolome for modulating microbiota are collectively discussed.


Assuntos
Microbiota , Metaboloma , Raízes de Plantas , Plantas , Microbiologia do Solo , Estresse Fisiológico
9.
Int J Mol Sci ; 23(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35008959

RESUMO

Bisdemethoxycurcumin (BDMC) has biological activities, including anticancer effects in vitro; however, its anticancer effects in human glioblastoma (GBM) cells have not been examined yet. This study aimed to evaluate the tumor inhibitory effect and molecular mechanism of BDMC on human GBM 8401/luc2 cells in vitro and in vivo. In vitro studies have shown that BDMC significantly reduced cell viability and induced cell apoptosis in GBM 8401/luc2 cells. Furthermore, BDMC induced apoptosis via inhibited Bcl-2 (anti-apoptotic protein) and increased Bax (pro-apoptotic proteins) and cytochrome c release in GBM 8401/luc2 cells in vitro. Then, twelve BALB/c-nude mice were xenografted with human glioblastoma GBM 8401/luc2 cancer cells subcutaneously, and the xenograft nude mice were treated without and with BDMC (30 and 60 mg/kg of BDMC treatment) every 3 days. GBM 8401/luc2 cell xenografts experiment showed that the growth of the tumors was significantly suppressed by BDMC administration at both doses based on the reduction of tumor size and weights. BDMC did not change the body weight and the H&E histopathology analysis of liver samples, indicating that BDMC did not induce systemic toxicity. Meanwhile, treatment with BDMC up-regulated the expressions of BAX and cleaved caspase-3, while it down-regulated the protein expressions of Bcl-2 and XIAP in the tumor tissues compared with the control group. This study has demonstrated that BDMC presents potent anticancer activity on the human glioblastoma GBM 8401/luc2 cell xenograft model by inducing apoptosis and inhibiting tumor cell proliferation and shows the potential for further development to the anti-GBM cancer drug.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Diarileptanoides/farmacologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Ciências Biocomportamentais , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Regulação da Expressão Gênica , Glioblastoma/tratamento farmacológico , Glioblastoma/etiologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
10.
New Phytol ; 230(1): 228-243, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33616937

RESUMO

Plant roots are specialized belowground organs that spatiotemporally shape their development in function of varying soil conditions. This root plasticity relies on intricate molecular networks driven by phytohormones, such as auxin and jasmonate (JA). Loss-of-function of the NOVEL INTERACTOR OF JAZ (NINJA), a core component of the JA signaling pathway, leads to enhanced triterpene biosynthesis, in particular of the thalianol gene cluster, in Arabidopsis thaliana roots. We have investigated the biological role of thalianol and its derivatives by focusing on Thalianol Synthase (THAS) and Thalianol Acyltransferase 2 (THAA2), two thalianol cluster genes that are upregulated in the roots of ninja mutant plants. THAS and THAA2 activity was investigated in yeast, and metabolite and phenotype profiling of thas and thaa2 loss-of-function plants was carried out. THAA2 was shown to be responsible for the acetylation of thalianol and its derivatives, both in yeast and in planta. In addition, THAS and THAA2 activity was shown to modulate root development. Our results indicate that the thalianol pathway is not only controlled by phytohormonal cues, but also may modulate phytohormonal action itself, thereby affecting root development and interaction with the environment.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Triterpenos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Oxilipinas , Raízes de Plantas/metabolismo , Transdução de Sinais
11.
Proc Natl Acad Sci U S A ; 114(29): E6005-E6014, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28673978

RESUMO

Sesterterpenoids are a rare terpene class harboring untapped chemodiversity and bioactivities. Their structural diversity originates primarily from the scaffold-generating sesterterpene synthases (STSs). In fungi, all six known STSs are bifunctional, containing C-terminal trans-prenyltransferase (PT) and N-terminal terpene synthase (TPS) domains. In plants, two colocalized PT and TPS gene pairs from Arabidopsis thaliana were recently reported to synthesize sesterterpenes. However, the landscape of PT and TPS genes in plant genomes is unclear. Here, using a customized algorithm for systematically searching plant genomes, we reveal a suite of physically colocalized pairs of PT and TPS genes for the biosynthesis of a large sesterterpene repertoire in the wider Brassicaceae. Transient expression of seven TPSs from A. thaliana, Capsella rubella, and Brassica oleracea in Nicotiana benthamiana yielded fungal-type sesterterpenes with tri-, tetra-, and pentacyclic scaffolds, and notably (-)-ent-quiannulatene, an enantiomer of the fungal metabolite (+)-quiannulatene. Protein and structural modeling analysis identified an amino acid site implicated in structural diversification. Mutation of this site in one STS (AtTPS19) resulted in premature termination of carbocation intermediates and accumulation of bi-, tri-, and tetracyclic sesterterpenes, revealing the cyclization path for the pentacyclic sesterterpene (-)-retigeranin B. These structural and mechanistic insights, together with phylogenetic analysis, suggest convergent evolution of plant and fungal STSs, and also indicate that the colocalized PT-TPS gene pairs in the Brassicaceae may have originated from a common ancestral gene pair present before speciation. Our findings further provide opportunities for rapid discovery and production of sesterterpenes through metabolic and protein engineering.


Assuntos
Brassicaceae/genética , Brassicaceae/metabolismo , Genoma de Planta , Proteínas de Plantas/genética , Sesterterpenos/biossíntese , Algoritmos , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Evolução Molecular , Mutação , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Sesterterpenos/genética , Nicotiana/genética , Nicotiana/metabolismo
12.
Bioorg Med Chem Lett ; 29(23): 126742, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648857

RESUMO

Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, occasionally causes severe central nervous system disorders in the risk zone where more than 3 billion people reside. Our prior studies demonstrated antiviral potential of 4,5-dihydrofuran-3-carboxylate compound CW-33 (ethyl 2-(3',5'-dimethylanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) and its derivative CW-33A ((ethyl 2-(2-fluoroanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) against JEV infection ((Int. J. Mol. Sci. 2016, 17: E1386; Sci. Rep. 2018, 8: 16595). This study synthesized six new CW-33 derivatives containing chloro, or bromo groups at the C-2, C-3, or C-4 of anilino ring of CW-33, and assessed the antiviral activity and mechanisms of these chloro- and bromo-anilino substitutedderivatives. CW-33K, CW-33L and CW-33M had the bromo-substituents at the C-2, C-3, or C-4 of anilino ring of CW-33, respectively, showing the higher anti-JEV activity than CW-33 and other derivatives. CW-33K (ethyl 2-(2-bromoanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate) exhibited the highest antiviral efficacy and therapeutic index. The IC50 value of CW-33K was less than 5 µM for reducing JEV-induced cytopathic effect, virus infectivity and virus yield. CW-33K significantly inhibited the JEV replication at the early and late stages, suppressing viral RNA synthesis and intracellular JEV particle production. The study demonstrated that the CW-33 derivative with a bromosubstitutionat the C-2 anilino ring improved the antiviral activity JEV, providing the structure-antiviral activity relationship for the development of anti-JEV agents.


Assuntos
Antivirais/uso terapêutico , Efeito Citopatogênico Viral/efeitos dos fármacos , Vírus da Encefalite Japonesa (Espécie)/efeitos dos fármacos , Antivirais/farmacologia , Humanos
13.
New Phytol ; 218(3): 1076-1088, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29528490

RESUMO

Triterpene synthases, also known as 2,3-oxidosqualene cyclases (OSCs), synthesize diverse triterpene skeletons that form the basis of an array of functionally divergent steroids and triterpenoids. Tetracyclic and pentacyclic triterpene skeletons are synthesized via protosteryl and dammarenyl cations, respectively. The mechanism of conversion between two scaffolds is not well understood. Here, we report a promiscuous OSC from rice (Oryza sativa) (OsOS) that synthesizes a novel pentacyclic triterpene orysatinol as its main product. The OsOS gene is widely distributed in indica subspecies of cultivated rice and in wild rice accessions. Previously, we have characterized a different OSC, OsPS, a tetracyclic parkeol synthase found in japonica subspecies. Phylogenetic and protein structural analyses identified three key amino acid residues (#732, #365, #124) amongst 46 polymorphic sites that determine functional conversion between OsPS and OsOS, specifically, the chair-semi(chair)-chair and chair-boat-chair interconversions. The different orientation of a fourth amino acid residue Y257 was shown to be important for functional conversion The discovery of orysatinol unlocks a new path to triterpene diversity in nature. Our findings also reveal mechanistic insights into the cyclization of oxidosqualene into tetra- and pentacyclic skeletons, and provide a new strategy to identify key residues determining OSC specificity.


Assuntos
Aminoácidos/metabolismo , Transferases Intramoleculares/química , Oryza/enzimologia , Sequência de Aminoácidos , Ciclização , Variação Genética , Transferases Intramoleculares/genética , Lanosterol/análogos & derivados , Lanosterol/química , Lanosterol/metabolismo , Oryza/genética , Filogenia , Especificidade por Substrato
14.
Molecules ; 23(8)2018 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-30104528

RESUMO

Many studies have demonstrated that berberine inhibited the cell migration and invasion in human cancer cell lines. However, the exact molecular mechanism of berberine inhibiting the cell migration and invasion of human melanoma A375.S2 and A375.S2/PLX (PLX4032 induced resistant A375.S2) skin cancer cells remains unknown. In this study, we investigated the anti-metastasis mechanisms of berberine in human melanoma cancer A375.S2 cells and A375.S2/PLX resistant cells in vitro. Berberine at low concentrations (0, 1, 1.5 and 2 µM) induced cell morphological changes and reduced the viable cell number and inhibited the mobility, migration, and invasion of A375.S2 cells that were assayed by wound healing and transwell filter. The gelatin zymography assay showed that berberine slightly inhibited MMP-9 activity in A375.S2 cells. Results from western blotting indicated that berberine inhibited the expression of MMP-1, MMP-13, E-cadherin, N-cadherin, RhoA, ROCK1, SOS-1, GRB2, Ras, p-ERK1/2, p-c-Jun, p-FAK, p-AKT, NF-κB, and uPA after 24 h of treatment, but increased the PKC and PI3K in A375.S2 cells. PLX4032 is an inhibitor of the BRAFV600E mutation and used for the treatment of cancer cells harboring activated BRAF mutations. Berberine decrease cell number and inhibited the cell mobility in the resistant A375.S2 (A375.S2/PLX, PLX4032 generated resistant A375.S2 cells). Based on these observations, we suggest that the potential of berberine as an anti-metastatic agent in melanoma that deserves to be investigated in more detail, including in vivo studies in future.


Assuntos
Berberina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Quinase 1 de Adesão Focal/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Humanos , Metaloproteinases da Matriz/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Metástase Neoplásica
15.
Angew Chem Int Ed Engl ; 57(5): 1291-1295, 2018 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-29194888

RESUMO

Sesterterpenoids are a relatively rare class of plant terpenes. Sesterterpene synthase (STS)-mediated cyclization of the linear C25 isoprenoid precursor geranylfarnesyl diphosphate (GFPP) defines sesterterpene scaffolds. So far only a very limited number of STSs have been characterized. The discovery of three new plant STSs is reported that produce a suite of sesterterpenes with unprecedented 6/11/5 and 6/6/7/5 fused ring systems when transiently co-expressed with a GFPP synthase in Nicotiana benthamiana. Structural elucidation, feeding experiments, and quantum chemical calculations suggest that these STSs catalyze an unusual cyclization path involving reprotonation, intramolecular 1,6 proton transfer, and concerted but asynchronous bicyclization events. The cyclization is diverted from those catalyzed by the characterized plant STSs by forming unified 15/5 bicyclic sesterterpene intermediates. Mutagenesis further revealed a conserved amino acid residue implicated in reprotonation.


Assuntos
Alquil e Aril Transferases/metabolismo , Proteínas de Plantas/metabolismo , Sesterterpenos/química , Alquil e Aril Transferases/classificação , Cátions/química , Ciclização , Cromatografia Gasosa-Espectrometria de Massas , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Proteínas de Plantas/classificação , Teoria Quântica , Sesterterpenos/metabolismo , Nicotiana/enzimologia , Nicotiana/metabolismo
16.
Environ Toxicol ; 32(1): 329-343, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26822499

RESUMO

Tetrandrine, a bisbenzylisoquinoline alkaloid, is extracted from the root of the Chinese herb Radix Stephania tetrandra S Moore. This compound has antitumor activity in different cancer cell types. In this study, the effects of tetrandrine on human oral cancer CAL 27 cells were examined. Results indicated that tetrandrine induced cytotoxic activity in CAL 27 cells. Effects were due to cell death by the induction of apoptosis and accompany with autophagy and these effects were concentration- and time-dependent manners. Tetrandrine induced apoptosis was accompanied by alterations in cell morphology, chromatin fragmentation, and caspase activation in CAL 27 cells. Tetrandrine treatment also induced intracellular accumulation of reactive oxygen species (ROS). The generation of ROS may play an important role in tetrandrine-induced apoptosis. Tetrandrine triggered LC3B expression and induced autophagy in CAL 27 cells. Tetrandrine induced apoptosis and autophagy were significantly attenuated by N-acetylcysteine pretreatment that supports the involvement of ROS production. Tetrandrine induced cell death may act through caspase-dependent apoptosis with Beclin-1-induced autophagy in human oral cancer cells. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 329-343, 2017.


Assuntos
Autofagia/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Benzilisoquinolinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Cálcio/metabolismo , Caspases/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica , Proteínas Associadas aos Microtúbulos/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia
17.
New Phytol ; 211(3): 771-89, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27112429

RESUMO

Contents 771 I. 771 II. 772 III. 780 IV. 781 V. 786 786 References 786 SUMMARY: Plant natural products are of great value for agriculture, medicine and a wide range of other industrial applications. The discovery of new plant natural product pathways is currently being revolutionized by two key developments. First, breakthroughs in sequencing technology and reduced cost of sequencing are accelerating the ability to find enzymes and pathways for the biosynthesis of new natural products by identifying the underlying genes. Second, there are now multiple examples in which the genes encoding certain natural product pathways have been found to be grouped together in biosynthetic gene clusters within plant genomes. These advances are now making it possible to develop strategies for systematically mining multiple plant genomes for the discovery of new enzymes, pathways and chemistries. Increased knowledge of the features of plant metabolic gene clusters - architecture, regulation and assembly - will be instrumental in expediting natural product discovery. This review summarizes progress in this area.


Assuntos
Genômica , Plantas/genética , Plantas/metabolismo , Produtos Biológicos/metabolismo , Vias Biossintéticas , Família Multigênica
18.
Environ Toxicol ; 31(12): 1899-1908, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26370218

RESUMO

Curcuminoids are the major natural phenolic compounds found in the rhizome of many Curcuma species. Curcuminoids consist of a mixture of curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC). Although numerous studies have shown that curcumin induced cell apoptosis in many human cancer cells, however, mechanisms of BDMC-inhibited cell growth and -induced apoptosis in human lung cancer cells still remain unclear. Herein, we investigated the effect of BDMC on the cell death via the cell cycle arrest and induction of apoptosis in NCI H460 human lung cancer cells. Flow cytometry assay was used to measure viable cells, cell cycle distribution, the productions of reactive oxygen species (ROS) and Ca2+ , mitochondrial membrane potential (ΔΨm ) and caspase-3, -8 and -9 activity. DNA damage and condension were assayed by Comet assay and DAPI staining, respectively. Western blotting was used to measure the changes of cell cycle and apoptosis associated protein expressions. Results indicated that BDMC significantly induced cell death through induced S phase arrest and induced apoptosis. Moreover, DMC induced DNA damage and condension, increased ROS and Ca2+ productions and decreased the levels of ΔΨm and promoted activities caspase-3, -8, and -9. Western blotting results showed that BDMC inhibited Cdc25A, cyclin A and E for causing S phase arrest, furthermore, promoted the expression of AIF, Endo G and PARP and the levels of Fas ligand (Fas L) and Fas were also up-regulated. Results also indicated that BDMC increased ER stress associated protein expression such as GRP78, GADD153, IRE1α, IRE1ß, ATF-6α, ATF-6ß, and caspase-4. Taken together, we suggest that BDMC induced cell apoptosis through multiple signal pathways such as extrinsic, intrinsic and ES tress pathway. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1899-1908, 2016.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Curcumina/análogos & derivados , Ciclina A/metabolismo , Ciclina E/metabolismo , Estresse do Retículo Endoplasmático , Mitocôndrias/metabolismo , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Curcumina/farmacologia , Dano ao DNA , Diarileptanoides , Chaperona BiP do Retículo Endoplasmático , Humanos , Neoplasias Pulmonares , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fase S , Transdução de Sinais/efeitos dos fármacos , Fosfatases cdc25/metabolismo
19.
Environ Toxicol ; 31(12): 1859-1868, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26332341

RESUMO

Nonsmall cell lung carcinoma (NSCLC) is a devastating primary lung tumor resistant to conventional therapies. Bisdemethoxycurcumin (BDMC) is one of curcumin derivate from Turmeric and has been shown to induce NSCLC cell death. Although there is one report to show BDMC induced DNA double strand breaks, however, no available information to show BDMC induced DNA damage action with inhibited DNA repair protein in lung cancer cells in detail. In this study, we tested BDMC-induced DNA damage and condensation in NCI-H460 cells by using Comet assay and DAPI staining examinations, respectively and we found BDMC induced DNA damage and condension. Western blotting was used to examine the effects of BDMC on protein expression associated with DNA damage and repair and results indicated that BDMC suppressed the protein levels associated with DNA damage and repair, such as 14-3-3σ (an important checkpoint keeper of DDR), O6-methylguanine-DNA methyltransferase, DNA repair proteins breast cancer 1, early onset, mediator of DNA damage checkpoint 1 but activate phosphorylated p53 and p-H2A.X (phospho Ser140) in NCI-H460 cells. Confocal laser systems microscopy was used for examining the protein translocation and results show that BDMC increased the translocation of p-p53 and p-H2A.X (phospho Ser140) from cytosol to nuclei in NCI-H460 cells. In conclusion, BDMC induced DNA damage and condension and affect DNA repair proteins in NCI-H460 cells in vitro. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1859-1868, 2016.


Assuntos
Antineoplásicos/farmacologia , Curcumina/análogos & derivados , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Diarileptanoides , Histonas/metabolismo , Humanos , Neoplasias Pulmonares , Fosforilação , Transporte Proteico/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
20.
Environ Toxicol ; 31(11): 1600-1611, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26122529

RESUMO

Prostate cancer is the most frequently diagnosed malignancy in men and the second highest contributor of male cancer mortality. The crude extract of Euphorbia formosana (CEEF) has been used for treatment of different diseases but the cytotoxic effects of CEEF on human cancer cells have not been reported. The purpose of the present experiments was to determine effects of CEEF on cell cycle distribution and induction of apoptosis in DU145 human prostate cancer cells in vitro. Contrast-phase microscope was used for examining cell morphological changes. Flow cytometric assays were used for cell viability, cell cycle, apoptosis, reactive oxygen species, and Ca2+ production and mitochondria membrane potential (ΔΨm ). Western blotting was used for examining protein expression of cell cycle and apoptosis associated proteins. Real-time PCR was used for examining mRNA levels of caspase-3, -8, and -9, AIF, and Endo G. Confocal laser microscope was used to examine the translocation of AIF, Endo G, and cytochrome in DU145 cells after CEEF exposure. CEEF-induced cell morphological changes, decreased the percentage of viable cells, and induced S phase arrest and apoptosis in DU145 cells. Furthermore, CEEF promoted RAS and Ca2+ production and reduced ΔΨm levels. Real-time QPCR confirmed that CEEF promoted the mRNA expression of caspase-3 and -9, AIF and Endo G and we found that AIF and Endo G and cytochrome c were released from mitochondria. Taken together, CEEF-induced cytotoxic effects via ROS production, induced S phase arrest and induction of apoptosis through caspase-dependent and independent and mitochondria-dependent pathways in DU245 cancer cells. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1600-1611, 2016.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/fisiologia , Euphorbia , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Mitocôndrias/fisiologia , Neoplasias da Próstata/patologia
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