Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
2.
Anticancer Agents Med Chem ; 23(12): 1351-1354, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959156

RESUMO

Neuroprotection is one of the hot topics in medicine. Alzheimer's disease, amyotrophic lateral sclerosis, retinal pigment epithelial (RPE) degeneration, and axonal degeneration have been studied for the involvement of NAD depletion. Localized NAD+ depletion could lead to overactivation and crowding of local NAD+ salvage pathways. It has been stated that NAD+ depletion caused by PARPs and PAR cycling has been related to metabolic diseases and cancer. Additionally, it is now acknowledged that SARM1 dependent NAD+ depletion causes axon degeneration. New targeted therapeutics, such as SARM1 inhibitors, and NAD+ salvage drugs will help alleviate the dysfunctions affecting cell life and death in neurodegeneration as well as in metabolic diseases and cancer.


Assuntos
Axônios , NAD , Humanos , Axônios/metabolismo , NAD/metabolismo
3.
Semin Cancer Biol ; 83: 197-207, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-32738290

RESUMO

Data obtained from cutting-edge research have shown that deregulated epigenetic marks are critical hallmarks of cancer. Rapidly emerging scientific evidence has helped in developing a proper understanding of the mechanisms leading to control of cellular functions, from changes in chromatin accessibility, transcription and translation, and in post-translational modifications. Firstly, mechanisms of DNA methylation and demethylation are introduced, as well as modifications of DNA and RNA, with particular focus on N6-methyladenosine (m6A), discussing the effects of these modifications in normal cells and in malignancies. Then, chromatin modifying proteins and remodelling complexes are discussed. Many enzymes and accessory proteins in these complexes have been found mutated or have undergone differential splicing, leading to defective protein complexes. Epigenetic mechanisms acting on nucleosomes by polycomb repressive complexes and on chromatin by SWI/SNF complexes on nucleosome assembly/disassembly, as well as main mutated genes linked to cancers, are reviewed. Among enzymes acting on histones and other proteins erasing the reversible modifications are histone deacetylases (HDACs). Sirtuins are of interest since most of these enzymes not only deacylate histones and other proteins, but also post-translationally modify proteins adding a Mono-ADP-ribose (MAR) moiety. MAR can be read by MACRO-domain containing proteins such as histone MacroH2A1, with specific function in chromatin assembly. Finally, recent advances are presented on non-coding RNAs with a scaffold function, prospecting their role in assembly of chromatin modifying complexes, recruiting enzyme players to chromatin regions. Lastly, the imbalance in metabolites production due to mitochondrial dysfunction is presented, with the potential of these metabolites to inhibit enzymes, either writers, readers or erasers of epitranscriptome marks. In the perspectives, studies are overwied on drugs under development aiming to limit excessive enzyme activities and to reactivate chromatin modifying complexes, for therapeutic application. This knowledge may lead to novel drugs and personalised medicine for cancer patients.


Assuntos
Histonas , Neoplasias , Cromatina/genética , Montagem e Desmontagem da Cromatina , Epigênese Genética , Histonas/genética , Histonas/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional
5.
Int J Mol Sci ; 22(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34639169

RESUMO

Among the post-translational modifications of proteins, ADP-ribosylation has been studied for over fifty years, and a large set of functions, including DNA repair, transcription, and cell signaling, have been assigned to this post-translational modification (PTM). This review presents an update on the function of a large set of enzyme writers, the readers that are recruited by the modified targets, and the erasers that reverse the modification to the original amino acid residue, removing the covalent bonds formed. In particular, the review provides details on the involvement of the enzymes performing monoADP-ribosylation/polyADP-ribosylation (MAR/PAR) cycling in cancers. Of note, there is potential for the application of the inhibitors developed for cancer also in the therapy of non-oncological diseases such as the protection against oxidative stress, the suppression of inflammatory responses, and the treatment of neurodegenerative diseases. This field of studies is not concluded, since novel enzymes are being discovered at a rapid pace.


Assuntos
ADP-Ribosilação , Neoplasias/tratamento farmacológico , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli Adenosina Difosfato Ribose/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Processamento de Proteína Pós-Traducional , Animais , Humanos , Neoplasias/metabolismo
8.
Curr Med Chem ; 28(41): 8453-8479, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33461448

RESUMO

Mitochondrial dysfunction and oxidative stress are prominent features of a plethora of human disorders. Dysregulation of mitochondrial functions represents a common pathogenic mechanism of diseases such as neurodegenerative disorders and cancer. The maintenance of the Nicotinamide adenine dinucleotide (NAD+) pool, and a positive NAD+/NADH ratio, are essential for mitochondrial and cell functions. The synthesis and degradation of NAD+ and transport of its key intermediates among cell compartments play an important role in maintaining optimal NAD levels, for the regulation of NAD+-utilizing enzymes, such as sirtuins (Sirt), poly-ADP-ribose polymerases, and CD38/157 enzymes, either intracellularly as well as extracellularly. In this review, we present and discuss the links between NAD+, NAD+-consuming enzymes, mitochondria functions, and diseases. Attempts to treat various diseases with supplementation of NAD+ cycling intermediates and inhibitors of sirtuins and ADP-ribosyl transferases may highlight a possible therapeutic approach for therapy of cancer and neurodegenerative diseases.


Assuntos
Neoplasias , Sirtuínas , ADP-Ribosilação , Humanos , Mitocôndrias/metabolismo , NAD , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Sirtuínas/metabolismo
9.
Cells ; 10(1)2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440786

RESUMO

Mono(ADP-ribose) transferases and mono(ADP-ribosyl)ating sirtuins use NAD+ to perform the mono(ADP-ribosyl)ation, a simple form of post-translational modification of proteins and, in some cases, of nucleic acids. The availability of NAD+ is a limiting step and an essential requisite for NAD+ consuming enzymes. The synthesis and degradation of NAD+, as well as the transport of its key intermediates among cell compartments, play a vital role in the maintenance of optimal NAD+ levels, which are essential for the regulation of NAD+-utilizing enzymes. In this review, we provide an overview of the current knowledge of NAD+ metabolism, highlighting the functional liaison with mono(ADP-ribosyl)ating enzymes, such as the well-known ARTD10 (also named PARP10), SIRT6, and SIRT7. To this aim, we discuss the link of these enzymes with NAD+ metabolism and chronic diseases, such as cancer, degenerative disorders and aging.


Assuntos
ADP-Ribosilação , Doença , Enzimas/metabolismo , NAD/metabolismo , Animais , Vias Biossintéticas , Humanos , Sirtuínas/metabolismo
10.
Antioxidants (Basel) ; 11(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35052524

RESUMO

The prominent cultivation of lemongrass (Cymbopogon spp.) relies on the pharmacological incentives of its essential oil. Lemongrass essential oil (LEO) carries a significant amount of numerous bioactive compounds, such as citral (mixture of geranial and neral), isoneral, isogeranial, geraniol, geranyl acetate, citronellal, citronellol, germacrene-D, and elemol, in addition to other bioactive compounds. These components confer various pharmacological actions to LEO, including antifungal, antibacterial, antiviral, anticancer, and antioxidant properties. These LEO attributes are commercially exploited in the pharmaceutical, cosmetics, and food preservations industries. Furthermore, the application of LEO in the treatment of cancer opens a new vista in the field of therapeutics. Although different LEO components have shown promising anticancer activities in vitro, their effects have not yet been assessed in the human system. Hence, further studies on the anticancer mechanisms conferred by LEO components are required. The present review intends to provide a timely discussion on the relevance of LEO in combating cancer and sustaining human healthcare, as well as in food industry applications.

11.
Anticancer Agents Med Chem ; 21(5): 567-574, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32628597

RESUMO

Trans-resveratrol (RESV), pterostilbene, trans-piceid and trans-viniferins are bioactive stilbenes present in grapes and other plants. Several groups applied biotechnology to introduce their synthesis in plant crops. Biochemical interaction with enzymes, regulation of non-coding RNAs, and activation of signaling pathways and transcription factors are among the main effects described in literature. However, solubility in ethanol, short half-life, metabolism by gut bacteria, make the concentration responsible for the effects observed in cultured cells difficult to achieve. Derivatives obtained by synthesis, trans-resveratrol analogs and methoxylated stilbenes show to be more stable and allow the synthesis of bioactive compounds with higher bioavailability. However, changes in chemical structure may require testing for toxicity. Thus, the delivery of RESV and its natural analogs incorporated into liposomes or nanoparticles, is the best choice to ensure stability during administration and appropriate absorption. The application of RESV and its derivatives with anti-inflammatory and anticancer activity is presented with description of novel clinical trials.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Sistemas de Liberação de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Resveratrol/farmacologia , Estilbenos/farmacologia , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Humanos , Lipossomos/química , Estrutura Molecular , Nanopartículas/química , Neoplasias/genética , Neoplasias/metabolismo , Resveratrol/síntese química , Resveratrol/química , Estilbenos/síntese química , Estilbenos/química
12.
Biosensors (Basel) ; 10(6)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549369

RESUMO

Pectobacterium atrosepticum (Pba) is a quarantine and threatening phytopathogen known as the causal agent of blackleg and soft rot disease of potatoes in many areas. Its early detection is then important to have healthy potato tubers and reduce economic losses. Today, conventional methods such as enzyme-linked immunosorbent-assay (ELISA) and polymerase chain reaction (PCR) are typically used for Pba detection, but they are expensive and time-consuming. Here we report on the optimization of an alternative approach based on an electrochemical impedance immunosensor combining a microfluidic module and a microelectrodes array, and having advantages in terms of low cost, ease of use and portability. For validation and for assessing its performance, the lab-on-chip platform has been compared with two standard methods (ELISA and PCR).


Assuntos
Técnicas Biossensoriais , Pectobacterium/isolamento & purificação , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia , Ensaio de Imunoadsorção Enzimática , Dispositivos Lab-On-A-Chip , Reação em Cadeia da Polimerase
13.
Materials (Basel) ; 13(4)2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075305

RESUMO

The employment of plant extracts in the synthesis of metal nanoparticles is a very attractive approach in the field of green synthesis. To benefit from the potential synergy between the biological activities of the Moringa oleifera and metallic bismuth, our study aimed to achieve a green synthesis of phytochemical encapsulated bismuth nanoparticles using a hydroalcoholic extract of M. oleifera leaves. The total phenolic content in the M. oleifera leaves extract used was 23.0 ± 0.3 mg gallic acid equivalent/g of dried M. oleifera leaves powder. The physical properties of the synthesized bismuth nanoparticles were characterized using UV-Vis spectrophotometer, FT-IR spectrometer, TEM, SEM, and XRD. The size of the synthesized bismuth nanoparticles is in the range of 40.4-57.8 nm with amorphous morphology. Using DPPH and phosphomolybdate assays, our findings revealed that the M. oleifera leaves extract and the synthesized bismuth nanoparticles possess antioxidant properties. Using resazurin microtiter assay, we also demonstrate that the M. oleifera leaves extract and the synthesized bismuth nanoparticles exert potent anti-bacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis (estimated MIC values for the extract: 500, 250, 250, and 250 µg/mL; estimated MIC values for the bismuth nanoparticles: 500, 500, 500, and 250 µg/mL, respectively). Similarly, the M. oleifera leaves extract and the synthesized bismuth nanoparticles display relatively stronger anti-fungal activity against Aspergillus niger, Aspergillus flavus, Candida albicans, and Candida glabrata (estimated MIC values for the extract: 62.5, 62.5, 125, and 250 µg/mL; estimated MIC values for the bismuth nanoparticles: 250, 250, 62.5, and 62.5 µg/mL, respectively). Thus, green synthesis of bismuth nanoparticles using M. oleifera leaves extract was successful, showing a positive antioxidant, anti-bacterial, and anti-fungal activity. Therefore, the synthesized bismuth nanoparticles can potentially be employed in the alleviation of symptoms associated with oxidative stress and in the topic treatment of Candida infections.

14.
Molecules ; 25(3)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012912

RESUMO

: The synthesis of metal nanoparticles using plant extracts is a very promising method in green synthesis. The medicinal value of Moringa oleifera leaves and the antimicrobial activity of metallic copper were combined in the present study to synthesize copper nanoparticles having a desirable added-value inorganic material. The use of a hydroalcoholic extract of M. oleifera leaves for the green synthesis of copper nanoparticles is an attractive method as it leads to the production of harmless chemicals and reduces waste. The total phenolic content in the M. oleifera leaves extract was 23.0 ± 0.3 mg gallic acid equivalent/g of dried M. oleifera leaves powder. The M. oleifera leaves extract was treated with a copper sulphate solution. A color change from brown to black indicates the formation of copper nanoparticles. Characterization of the synthesized copper nanoparticles was performed using ultraviolet-visible light (UV-Vis) spectrophotometry, Fourier-transform infrared (FTIR) spectrometry, high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The synthesized copper nanoparticles have an amorphous nature and particle size of 35.8-49.2 nm. We demonstrate that the M. oleifera leaves extract and the synthesized copper nanoparticles display considerable antioxidant activity. Moreover, the M. oleifera leaves extract and the synthesized copper nanoparticles exert considerable anti-bacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis (MIC values for the extract: 500, 250, 250, and 250 µg/mL; MIC values for the copper nanoparticles: 500, 500, 500, and 250 µg/mL, respectively). Similarly, the M. oleifera leaves extract and the synthesized copper nanoparticles exert relatively stronger anti-fungal activity against Aspergillus niger, Aspergillus flavus, Candida albicans, and Candida glabrata (MIC values for the extract: 62.5, 62.5, 125, and 250 µg/mL; MIC values for the copper nanoparticles: 125, 125, 62.5, and 31.2 µg/mL, respectively). Our study reveals that the green synthesis of copper nanoparticles using a hydroalcoholic extract of M. oleifera leaves was successful. In addition, the synthesized copper nanoparticles can be potentially employed in the treatment of various microbial infections due to their reported antioxidant, anti-bacterial, and anti-fungal activities.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Cobre/química , Moringa oleifera/química , Fenóis/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Antioxidantes/síntese química , Antioxidantes/química , Bactérias/efeitos dos fármacos , Cápsulas , Fungos/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Extratos Vegetais/química , Folhas de Planta/química
15.
Foods ; 8(9)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540237

RESUMO

Microbial characterization of two Italian traditional cheeses, Giuncata and Caciotta Leccese, was carried out, with the aim to isolate autochthonous bacterial strains to be used as starters to improve and standardize the quality of these cheeses. More than 400 bacterial isolates were found, using PCR-based identification, to belong to 12 species of the Streptococcus, Lactococcus, Lactobacillus, and Leuconostoc genera. The dominant strains were screened for antagonistic activity against pathogenic and spoilage bacteria and exopolysaccharide production, acidification, and proteolytic activity. Since Streptococcus macedonicus was found to be the most prevalent lactic acid bacteria species present in milk and in both types of cheese, the best performing strain of this species was successfully used, alone or in combination with a selected autochthonous Lactococcus lactis strain, in pilot-scale productions of Giuncata and Caciotta Leccese cheeses, respectively. The combined inoculums of selected autochthonous strains positively influenced the sensory characteristics of both Giuncata and Caciotta cheeses. Finally, the selected autochthonous cultures were enriched with a potentially probiotic Lactobacillus rhamnosus strain and successfully used in pilot-scale productions of these traditional cheeses. To the best of our knowledge, this is the first study reporting the use of an autochthonous S. macedonicus strain as a starter for the production of cheeses with added probiotics. In addition, the identification of the probiotic strain in the feces of healthy volunteers fed with the advanced traditional cheese proved its effectiveness as a carrier for the delivery of probiotics to the human body.

18.
Mol Plant Pathol ; 20(6): 751-764, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30938041

RESUMO

The transfer of well-studied native and chimeric pattern recognition receptors (PRRs) to susceptible plants is a proven strategy to improve host resistance. In most cases, the ectodomain determines PRR recognition specificity, while the endodomain determines the intensity of the immune response. Here we report the generation and characterization of the chimeric receptor EFR-Cf-9, which carries the ectodomain of the Arabidopsis thaliana EF-Tu receptor (EFR) and the endodomain of the tomato Cf-9 resistance protein. Both transient and stable expression of EFR-Cf-9 triggered a robust hypersensitive response (HR) upon elf18 treatment in tobacco. Co-immunoprecipitation and virus-induced gene silencing studies showed that EFR-Cf-9 constitutively interacts with SUPPRESSOR OF BIR1-1 (SOBIR1) co-receptor, and requires both SOBIR1 and kinase-active BRI1-ASSOCIATED KINASE1 (BAK1) for its function. Transgenic plants expressing EFR-Cf-9 were more resistant to the (hemi)biotrophic bacterial pathogens Pseudomonas amygdali pv. tabaci (Pta) 11528 and Pseudomonas syringae pv. tomato DC3000, and mounted an HR in response to high doses of Pta 11528 and P. carotovorum. Taken together, these data indicate that the EFR-Cf-9 chimera is a valuable tool for both investigating the molecular mechanisms responsible for the activation of defence responses by PRRs, and for potential biotechnological use to improve crop disease resistance.


Assuntos
Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/microbiologia , Arabidopsis/imunologia , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Resistência à Doença/genética , Resistência à Doença/fisiologia , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/imunologia , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiologia , Fator Tu de Elongação de Peptídeos/genética , Fator Tu de Elongação de Peptídeos/metabolismo , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Imunidade Vegetal/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Receptores de Reconhecimento de Padrão/imunologia , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Nicotiana/imunologia , Nicotiana/metabolismo , Nicotiana/microbiologia
19.
Cancers (Basel) ; 11(4)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987378

RESUMO

There has been a renewed interest in the identification of natural products having premium pharmacological properties and minimum off-target effects. In accordance with this approach, natural product research has experienced an exponential growth in the past two decades and has yielded a stream of preclinical and clinical insights which have deeply improved our knowledge related to the multifaceted nature of cancer and strategies to therapeutically target deregulated signaling pathways in different cancers. In this review, we have set the spotlight on the scientifically proven ability of berberine to effectively target a myriad of deregulated pathways.

20.
Semin Cancer Biol ; 58: 47-55, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30742906

RESUMO

Epigenetic abnormalities and aberrant expression of non-coding RNAs are two emerging features of cancer cells, both of which are responsible for deregulated gene expression. In this review, we describe the interplay between the two. Specific themes include epigenetic silencing of tumor suppressor miRNAs, epigenetic activation of oncogenic miRNAs, epigenetic aberrations caused by miRNAs, and naturally occurring compounds which modulate miRNA expression through epigenetic mechanisms.


Assuntos
Epigênese Genética/genética , MicroRNAs/genética , Neoplasias/genética , Animais , Carcinogênese/genética , Epigenômica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Oncogenes/genética , RNA não Traduzido/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA