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1.
Int J Mol Sci ; 24(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37762072

RESUMO

CDK-1 and PARP-1 play crucial roles in breast cancer progression. Compounds acting as CDK-1 and/or PARP-1 inhibitors can induct cell death in breast cancer with a selective synthetic lethality mechanism. A mixed treatment by means of CDK-1 and PARP-1 inhibitors resulted in radical breast cancer cell growth reduction. Inhibitors with a dual target mechanism of action could arrest cancer progression by simultaneously blocking the DNA repair mechanism and cell cycle, resulting in advantageous monotherapy. To this aim, in the present work, we identified compound 645656 with a significant affinity for both CDK-1 and PARP-1 by a mixed ligand- and structure-based virtual screening protocol. The Biotarget Predictor Tool was used at first in a Multitarget mode to filter the large National Cancer Institute (NCI) database. Then, hierarchical docking studies were performed to further screen the compounds and evaluate the ligands binding mode, whose putative dual-target mechanism of action was investigated through the correlation between the antiproliferative activity data and the target proteins' (CDK-1 and PARP-1) expression pattern. Finally, a Molecular Dynamics Simulation confirmed the high stability of the most effective selected compound 645656 in complex with both PARP-1 and CDK-1.


Assuntos
Antineoplásicos , Mamoplastia , Neoplasias , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Ligantes , Antineoplásicos/farmacologia , Ciclo Celular
2.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36555550

RESUMO

Plant biostimulants are formulations that are experiencing great success from the perspective of sustainable agriculture. In this work, we evaluated the effect derived from the application of a biostimulant based on algae and yeast extracts (Expando®) on the agronomic yield and nutraceutical profile of two different cultivars ("Sugar Time" and "West Rose") of Prunus persica (peach). Although, at the agronomic level, significant effects on production yields were not recorded, the biostimulant was able to reduce the ripening time, increase the fruit size, and make the number of harvestable fruits homogeneous. From a nutraceutical point of view, our determinations via spectrophotometric (UV/Vis) and chromatographic (HPLC-DAD-MS/MS) analysis showed that the biostimulant was able to boost the content of bioactive compounds in both the pulp (5.0 L/ha: +17%; 4.0 L/ha: +12%; 2.5 L/ha: +11%) and skin (4.0 L/ha: +38%; 2.5 L/ha: +15%). These changes seem to follow a dose-dependent effect, also producing attractive effects on the antioxidant properties of the fruits harvested from the treated trees. In conclusion, the biostimulant investigated in this work proved to be able to produce more marketable fruit in a shorter time, both from a pomological and a functional point of view.


Assuntos
Prunus persica , Alga Marinha , Antioxidantes/química , Prunus persica/química , Frutas/química , Espectrometria de Massas em Tandem , Compostos Fitoquímicos/análise , Extratos Vegetais/química
3.
Int J Mol Sci ; 23(22)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36430850

RESUMO

In vitro antiproliferative assays still represent one of the most important tools in the anticancer drug discovery field, especially to gain insights into the mechanisms of action of anticancer small molecules. The NCI-DTP (National Cancer Institute Developmental Therapeutics Program) undoubtedly represents the most famous project aimed at rapidly testing thousands of compounds against multiple tumor cell lines (NCI60). The large amount of biological data stored in the National Cancer Institute (NCI) database and many other databases has led researchers in the fields of computational biology and medicinal chemistry to develop tools to predict the anticancer properties of new agents in advance. In this work, based on the available antiproliferative data collected by the NCI and the manipulation of molecular descriptors, we propose the new in silico Antiproliferative Activity Predictor (AAP) tool to calculate the GI50 values of input structures against the NCI60 panel. This ligand-based protocol, validated by both internal and external sets of structures, has proven to be highly reliable and robust. The obtained GI50 values of a test set of 99 structures present an error of less than ±1 unit. The AAP is more powerful for GI50 calculation in the range of 4-6, showing that the results strictly correlate with the experimental data. The encouraging results were further supported by the examination of an in-house database of curcumin analogues that have already been studied as antiproliferative agents. The AAP tool identified several potentially active compounds, and a subsequent evaluation of a set of molecules selected by the NCI for the one-dose/five-dose antiproliferative assays confirmed the great potential of our protocol for the development of new anticancer small molecules. The integration of the AAP tool in the free web service DRUDIT provides an interesting device for the discovery and/or optimization of anticancer drugs to the medicinal chemistry community. The training set will be updated with new NCI-tested compounds to cover more chemical spaces, activities, and cell lines. Currently, the same protocol is being developed for predicting the TGI (total growth inhibition) and LC50 (median lethal concentration) parameters to estimate toxicity profiles of small molecules.


Assuntos
Antineoplásicos , Curcumina , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Bases de Dados Factuais
4.
Bioinformatics ; 36(5): 1562-1569, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31605102

RESUMO

MOTIVATION: New in silico tools to predict biological affinities for input structures are presented. The tools are implemented in the DRUDIT (DRUgs DIscovery Tools) web service. The DRUDIT biological finder module is based on molecular descriptors that are calculated by the MOLDESTO (MOLecular DEScriptors TOol) software module developed by the same authors, which is able to calculate more than one thousand molecular descriptors. At this stage, DRUDIT includes 250 biological targets, but new external targets can be added. This feature extends the application scope of DRUDIT to several fields. Moreover, two more functions are implemented: the multi- and on/off-target tasks. These tools applied to input structures allow for predicting the polypharmacology and evaluating the collateral effects. RESULTS: The applications described in the article show that DRUDIT is able to predict a single biological target, to identify similarities among biological targets, and to discriminate different target isoforms. The main advantages of DRUDIT for the scientific community lie in its ease of use by worldwide scientists and the possibility to be used also without specific, and often expensive, hardware and software. In fact, it is fully accessible through the WWW from any device to perform calculations. Just a click or a tap can start tasks to predict biological properties for new compounds or repurpose drugs, lead compounds, or unsuccessful compounds. To date, DRUDIT is supported by four servers each able to execute 8 jobs simultaneously. AVAILABILITY AND IMPLEMENTATION: The web service is accessible at the www.drudit.com URL and its use is free of charge. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Polifarmacologia , Software , Simulação por Computador , Descoberta de Drogas , Internet
5.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576159

RESUMO

Melatonin is a ubiquitous indolamine, largely investigated for its key role in the regulation of several physiological processes in both animals and plants. In the last century, it was reported that this molecule may be produced in high concentrations by several species belonging to the plant kingdom and stored in specialized tissues. In this review, the main information related to the chemistry of melatonin and its metabolism has been summarized. Furthermore, the biosynthetic pathway characteristics of animal and plant cells have been compared, and the main differences between the two systems highlighted. Additionally, in order to investigate the distribution of this indolamine in the plant kingdom, distribution cluster analysis was performed using a database composed by 47 previously published articles reporting the content of melatonin in different plant families, species and tissues. Finally, the potential pharmacological and biostimulant benefits derived from the administration of exogenous melatonin on animals or plants via the intake of dietary supplements or the application of biostimulant formulation have been largely discussed.


Assuntos
Melatonina/metabolismo , Plantas/metabolismo , Animais , Análise por Conglomerados , Suplementos Nutricionais , Indóis/metabolismo
6.
Int J Mol Sci ; 22(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918281

RESUMO

The cell division cycle 25 (Cdc25) protein family plays a crucial role in controlling cell proliferation, making it an excellent target for cancer therapy. In this work, a set of small molecules were identified as Cdc25 modulators by applying a mixed ligand-structure-based approach and taking advantage of the correlation between the chemosensitivity of selected structures and the protein expression pattern of the proposed target. In the first step of the in silico protocol, a set of molecules acting as Cdc25 inhibitors were identified through a new ligand-based protocol and the evaluation of a large database of molecular structures. Subsequently, induced-fit docking (IFD) studies allowed us to further reduce the number of compounds biologically screened. In vitro antiproliferative and enzymatic inhibition assays on the selected compounds led to the identification of new structurally heterogeneous inhibitors of Cdc25 proteins. Among them, J3955, the most active inhibitor, showed concentration-dependent antiproliferative activity against HepG2 cells, with GI50 in the low micromolar range. When J3955 was tested in cell-cycle perturbation experiments, it caused mitotic failure by G2/M-phase cell-cycle arrest. Finally, Western blotting analysis showed an increment of phosphorylated Cdk1 levels in cells exposed to J3955, indicating its specific influence in cellular pathways involving Cdc25 proteins.


Assuntos
Fosfatases cdc25/antagonistas & inibidores , Sítios de Ligação , Proteína Quinase CDC2/metabolismo , Simulação por Computador , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Ligantes , Terapia de Alvo Molecular , Fosforilação/efeitos dos fármacos , Fosfatases cdc25/metabolismo
7.
Int J Mol Sci ; 22(5)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800828

RESUMO

Hypercholesterolemia is one of the major causes of cardiovascular disease, the risk of which is further increased if other forms of dyslipidemia occur. Current therapeutic strategies include changes in lifestyle coupled with drug administration. Statins represent the most common therapeutic approach, but they may be insufficient due to the onset of resistance mechanisms and side effects. Consequently, patients with mild hypercholesterolemia prefer the use of food supplements since these are perceived to be safer. Here, we investigate the phytochemical profile and cholesterol-lowering potential of Protium heptaphyllum gum resin extract (PHE). Chemical characterization via HPLC-APCI-HRMS2 and GC-FID/MS identified 13 compounds mainly belonging to ursane, oleanane, and tirucallane groups. Studies on human hepatocytes have revealed how PHE is able to reduce cholesterol production and regulate the expression of proteins involved in its metabolism. (HMGCR, PCSK9, LDLR, FXR, IDOL, and PPAR). Moreover, measuring the inhibitory activity of PHE against HMGR, moderate inhibition was recorded. Finally, molecular docking studies identified acidic tetra- and pentacyclic triterpenoids as the main compounds responsible for this action. In conclusion, our study demonstrates how PHE may be a useful alternative to contrast hypercholesterolemia, highlighting its potential as a sustainable multitarget natural extract for the nutraceutical industry that is rapidly gaining acceptance as a source of health-promoting compounds.


Assuntos
Anticolesterolemiantes/farmacologia , Hidrogênio/química , Gomas Vegetais/química , Resinas Vegetais/química , Triterpenos/farmacologia , Anticolesterolemiantes/isolamento & purificação , Domínio Catalítico/efeitos dos fármacos , Colesterol/metabolismo , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Avaliação Pré-Clínica de Medicamentos , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lovastatina/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , Triterpenos/isolamento & purificação
8.
Molecules ; 26(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299583

RESUMO

Background: G-quadruplex (G4) forming sequences are recurrent in telomeres and promoter regions of several protooncogenes. In normal cells, the transient arrangements of DNA in G-tetrads may regulate replication, transcription, and translation processes. Tumors are characterized by uncontrolled cell growth and tissue invasiveness and some of them are possibly mediated by gene expression involving G-quadruplexes. The stabilization of G-quadruplex sequences with small molecules is considered a promising strategy in anticancer targeted therapy. Methods: Molecular virtual screening allowed us identifying novel symmetric bifunctionalized naphtho[1,2-b:8,7-b']dithiophene ligands as interesting candidates targeting h-Telo and c-MYC G-quadruplexes. A set of unexplored naphtho-dithiophene derivatives has been synthesized and biologically tested through in vitro antiproliferative assays and spectroscopic experiments in solution. Results: The analysis of biological and spectroscopic data highlighted noteworthy cytotoxic effects on HeLa cancer cell line (GI50 in the low µM range), but weak interactions with G-quadruplex c-MYC promoter. Conclusions: The new series of naphtho[1,2-b:8,7-b']dithiophene derivatives, bearing the pharmacophoric assumptions necessary to stabilize G-quadruplexes, have been designed and successfully synthesized. The interesting antiproliferative results supported by computer aided rational approaches suggest that these studies are a significant starting point for a lead optimization process and the isolation of a more efficacious set of G-quadruplexes stabilizers.


Assuntos
Antineoplásicos , Proliferação de Células/efeitos dos fármacos , Citotoxinas , Quadruplex G/efeitos dos fármacos , Naftóis , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Células HeLa , Humanos , Naftóis/síntese química , Naftóis/química , Naftóis/farmacologia , Proteínas Proto-Oncogênicas c-myc/biossíntese
9.
Molecules ; 25(11)2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32512771

RESUMO

Annona cherimola (Cherimoya) and Annona atemoya (Atemoya) are tropical plants known for their edible fruit. Scientific data suggest that their leaves, used in traditional medicine in the form of teas or infusions without evidence of toxicity, contain several bioactive compounds. However, only Annona muricata among all the Annona species is currently used in the nutraceutical field, and its dried leaves are marketed for tea preparation. In this work, we explored the nutraceutical potential of Atemoya and Cherimoya leaves, by evaluating their chemical profile and functional properties. Phytochemical analyses showed large amounts of phenolic compounds, in particular proanthocyanidins, and identified 18 compounds, either flavonoids or alkaloids. Concerning biological activity, we found antioxidative properties correlated with polyphenols, and antiproliferative activity against HeLa and HepG2 cell lines correlated with alkaloids. The obtained results demonstrate the potential use of Annona cherimola leaves for the preparation of dietary supplements aimed to promote the physiological redox balance. Moreover, the varietal comparison suggests that two commercial cultivars (Campas and White) and the local Torre 1, better suit this purpose. On the other hand, among the studied cultivars, Campas and Torre 1 are also the richest in alkaloids and, in consideration of the anti-proliferative properties of their extracts, dietary supplements based on these cultivars might also have chemo-preventive effects.


Assuntos
Annona/química , Antioxidantes/farmacologia , Neoplasias/patologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Polifenóis/farmacologia , Annona/classificação , Apoptose , Proliferação de Células , Humanos , Neoplasias/tratamento farmacológico , Células Tumorais Cultivadas
10.
J Pineal Res ; 67(3): e12598, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349378

RESUMO

Melatonin is the main secretory product of the pineal gland, and it is involved in the regulation of periodic events. A melatonin production independent of the photoperiod is typical of the gut. However, the local physiological role of melatonin at the intestinal tract is poorly characterized. In this study, we evaluated the anti-inflammatory activities of melatonin in an in vitro model of inflamed intestinal epithelium. To this purpose, we assessed different parameters usually associated with intestinal inflammation using IL-1ß-stimulated Caco-2 cells. Differentiated monolayers of Caco-2 cells were preincubated with melatonin (1 nmol/L-50 µmol/L) and then exposed to IL-1ß. After each treatment, different inflammatory mediators, DNA-breakage, and global DNA methylation status were assayed. To evaluate the involvement of melatonin membrane receptors, we also exposed differentiated monolayers to melatonin in the presence of luzindole, a MT1 and MT2 antagonist. Our results showed that melatonin, at concentrations similar to those obtained in the lumen gut after ingestion of dietary supplements for the treatment of sleep disorders, was able to attenuate the inflammatory response induced by IL-1ß. Anti-inflammatory effects were expressed as both a decrease of the levels of inflammatory mediators, including IL-6, IL-8, COX-2, and NO, and a reduced increase in paracellular permeability. Moreover, the protection was associated with a reduced NF-κB activation and a prevention of DNA demethylation. Conversely, luzindole did not reverse the melatonin inhibition of stimulated-IL-6 release. In conclusion, our findings suggest that melatonin, through a local action, can modulate inflammatory processes at the intestinal level, offering new opportunities for a multimodal management of IBD.


Assuntos
Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-1beta/farmacologia , Intestinos/citologia , Melatonina/uso terapêutico , Células CACO-2 , Diferenciação Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Metilação de DNA/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
J Sci Food Agric ; 99(3): 1038-1045, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30014464

RESUMO

BACKGROUND: Pomegranate fruits are a rich source of polyphenols with numerous health-promoting effects. Pomegranate juices of five genotypes ('Mollar', 'Kingdom', 'Dente di Cavallo', and two old populations 'Francofonte' and 'Santa Tecla') were evaluated regarding anthocyanin and non-anthocyanin phenolic contents using ultrahigh performance liquid chromatography (UHPLC)-Orbitrap-mass spectrometry (MS). Moreover, total antioxidant activity (TAA) was evaluated using a 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assay. RESULTS: Twenty-three phenolic compounds were identified. Cyanidin-3,5-O-diglucoside and pelargonidin-3,5-O-diglucoside were the most representative anthocyanins in all genotypes; the Santa Tecla population had the highest content of these anthocyanins, 97.64 mg L-1 and 40.29 mg L-1 respectively. In the Francofonte population, ferulic acid hexoside was the most abundant compound (391.18 mg L-1 ). TAA values ranged between 221.5 and 36.73 µmol Trolox equivalents/100 mL of juice. A high TAA value was recorded for the Santa Tecla pomegranate population. CONCLUSION: The UHPLC-Orbitrap-MS approach was employed for the first time to identify the phenolic compound profiling in five pomegranate genotypes. TAA was analysed using an ABTS assay, and the results showed a significant variability in nutraceutical potential of the pomegranate genotypes studied. The inclusion of phenolic information in the linear discriminant analysis allowed very good discriminations among genotypes to be obtained. © 2018 Society of Chemical Industry.


Assuntos
Antioxidantes/análise , Frutas/química , Lythraceae/química , Antocianinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Sucos de Frutas e Vegetais/análise , Genótipo , Itália , Lythraceae/genética , Fenóis , Espectrometria de Massas em Tandem
12.
Inflamm Res ; 67(4): 327-337, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29256007

RESUMO

OBJECTIVE AND DESIGN: Epigenetic regulation is important in the activation of inflammatory cells. In the present study, we evaluated if DNA-methylation variations are involved in Interleukin-1ß (IL-1ß)-induced intestinal epithelial cells activation. MATERIALS AND METHODS: Differentiated Caco-2 cells were exposed to IL-1ß or to 5-azadeoxycytidine (5-azadC) for 24 or 48 h. Genome-wide methylation status was evaluated, while DNA methylation status at the promoter region of the gene encoding interleukin-6, 8 and 10 (IL-6, 8 and 10) was estimated. The levels of the corresponding gene products as well as DNA methyltransferases (DNMTs) quantity were assessed. RESULTS: IL-1ß decreased genomic methylation of human intestinal epithelial cells and induced demethylation at cg-specific sites at the promoter of pro-inflammatory genes IL6 and IL8; conversely it did not change the methylation of the IL10 promoter. IL-1ß also increased the release of IL-6 and IL-8 but did not change the IL-10 expression. Finally, cell exposure to IL-1ß decreased the DNMT3b expression, increased DNMT3a and was not able to change DNMT1 expression. CONCLUSIONS: Our results suggest a potential role of IL-1ß as modulator of DNA methylation in activated differentiated Caco-2 cell line.


Assuntos
Metilação de DNA , Interleucina-1beta/fisiologia , Interleucinas/genética , Mucosa Intestinal/metabolismo , Regiões Promotoras Genéticas , Células CACO-2 , Metilases de Modificação do DNA/metabolismo , Epigênese Genética , Humanos , Mediadores da Inflamação/metabolismo , Interleucinas/metabolismo
13.
Cell Physiol Biochem ; 34(4): 1075-89, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25228229

RESUMO

BACKGROUND/AIMS: Oxysterol activity on the erythrocyte (RBC) programmed cell death (eryptosis) had not been studied yet. Effects of an oxysterol mixture in hyper-cholesterolemic-relevant proportion, and of individual compounds, were investigated on RBCs from healthy humans. METHODS: Membrane phosphatidylserine (PS) externalization, calcium entry, ROS production, amino-phospholipid translocase (APLT) activity were evaluated by cytofluorimetric assays, cell volume from forward scatter. Prostaglandin PGE2 was measured by ELISA; GSH-adducts and lipoperoxides by spectrophotometry. Involvement of protein kinase C and caspase was investigated by inhibitors staurosporin, calphostin C, and Z-DEVD-FMK, respectively. RESULTS: Oxysterols caused PS externalization and cell shrinkage, associated with PGE2release, opening of PGE2-dependent calcium channels, ROS production, GSH depletion, membrane lipid oxidation. Addition of antioxidants prevented Ca(2+) influx and eryptosis. Calcium removal prevented cell shrinkage, with small effect (-20%) on the PS exposure, whereas ROS generation was unaltered. Either in the presence or absence of calcium i) oxysterols inhibited APLT, ii) staurosporin, calphostin C, Z-DEVD-FMK blunted and iii) antioxidants fully prevented the oxysterol-induced PS externalization. Only 7-ketocholesterol and cholestan-3ß,5α,6ß-triol were individually active. Eryptosis was observed in RBCs isolated after ex vivo spiking of human whole blood with the oxysterol mixture. CONCLUSIONS: Oxysterols induce an oxidative stress-dependent eryptosis, involving calcium-independent mechanisms. Eryptotic activity of oxysterols may be relevant in vivo.


Assuntos
Apoptose/fisiologia , Eritrócitos/metabolismo , Eritrócitos/patologia , Hipercolesterolemia/patologia , Estresse Oxidativo/fisiologia , Antioxidantes/metabolismo , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Caspases/metabolismo , Dinoprostona/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Cetocolesteróis/metabolismo , Fosfatidilserinas/metabolismo , Proteína Quinase C/metabolismo , Espécies Reativas de Oxigênio/metabolismo
14.
Biochem Biophys Res Commun ; 450(1): 652-8, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24937448

RESUMO

Phytochemicals may exert chemo-preventive effects on cells of the gastro-intestinal tract by modulating epigenome-regulated gene expression. The effect of the aqueous extract from the edible fruit of Opuntia ficus-indica (OFI extract), and of its betalain pigment indicaxanthin (Ind), on proliferation of human colon cancer Caco-2 cells has been investigated. Whole extract and Ind caused a dose-dependent apoptosis of proliferating cells at nutritionally relevant amounts, with IC50 400±25 mg fresh pulp equivalents/mL, and 115±15 µM (n=9), respectively, without toxicity for post-confluent differentiated cells. Ind accounted for ∼80% of the effect of the whole extract. Ind did not cause oxidative stress in proliferating Caco-2 cells. Epigenomic activity of Ind was evident as de-methylation of the tumor suppressor p16(INK4a) gene promoter, reactivation of the silenced mRNA expression and accumulation of p16(INK4a), a major controller of cell cycle. As a consequence, decrease of hyper-phosphorylated, in favor of the hypo-phosphorylated retinoblastoma was observed, with unaltered level of the cycline-dependent kinase CDK4. Cell cycle showed arrest in the G2/M-phase. Dietary cactus pear fruit and Ind may have chemo-preventive potential in intestinal cells.


Assuntos
Apoptose/efeitos dos fármacos , Betaxantinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina/agonistas , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Opuntia/química , Extratos Vegetais/farmacologia , Piridinas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Betaxantinas/química , Betaxantinas/isolamento & purificação , Células CACO-2 , Humanos , Piridinas/química , Piridinas/isolamento & purificação
15.
Bioorg Med Chem Lett ; 24(15): 3291-7, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24986661

RESUMO

New benzothieno[3,2-d]-1,2,3-triazines, together with precursors triazenylbenzo[b]thiophenes, were designed, synthesized and screened as anticancer agents. The structural features of these compounds prompted us to investigate their DNA binding capability through UV-vis absorption titrations, circular dichroism, and viscometry, pointing out the occurrence of groove-binding. The derivative 3-(4-methoxy-phenyl)benzothieno[3,2-d]-1,2,3-triazin-4(3H)-one showed the highest antiproliferative effect against HeLa cells and was also tested in cell cycle perturbation experiments. The obtained results assessed for the first time the anticancer activity of benzothieno[3,2-d]-1,2,3-triazine nucleus, and we related it to its DNA-binding properties.


Assuntos
Antineoplásicos/farmacologia , Tiofenos/farmacologia , Triazinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dicroísmo Circular , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Estrutura Molecular , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade , Tiofenos/síntese química , Tiofenos/química , Triazinas/síntese química , Triazinas/química , Viscosidade
16.
Proc Biol Sci ; 280(1768): 20130959, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23926145

RESUMO

Circadian clocks are endogenous approximately 24 h oscillators that temporally regulate many physiological and behavioural processes. In order to be beneficial for the organism, these clocks must be synchronized with the environmental cycles on a daily basis. Both light : dark and the concomitant daily temperature cycles (TCs) function as Zeitgeber ('time giver') and efficiently entrain circadian clocks. The temperature receptors mediating this synchronization have not been identified. Transient receptor potential (TRP) channels function as thermo-receptors in animals, and here we show that the Pyrexia (Pyx) TRP channel mediates temperature synchronization in Drosophila melanogaster. Pyx is expressed in peripheral sensory organs (chordotonal organs), which previously have been implicated in temperature synchronization. Flies deficient for Pyx function fail to synchronize their behaviour to TCs in the lower range (16-20°C), and this deficit can be partially rescued by introducing a wild-type copy of the pyx gene. Synchronization to higher TCs is not affected, demonstrating a specific role for Pyx at lower temperatures. In addition, pyx mutants speed up their clock after being exposed to TCs. Our results identify the first TRP channel involved in temperature synchronization of circadian clocks.


Assuntos
Relógios Circadianos/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/fisiologia , Temperatura , Canais de Potencial de Receptor Transitório/fisiologia , Animais , Temperatura Corporal , Escuridão , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Fotoperíodo , Canais de Potencial de Receptor Transitório/genética , Canais de Potencial de Receptor Transitório/metabolismo
17.
Br J Nutr ; 110(2): 230-40, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23228674

RESUMO

7-Ketocholesterol (7-KC)-induced apoptosis of macrophages is considered a key event in the development of human atheromas. In the present study, the effect of indicaxanthin (Ind), a bioactive pigment from cactus pear fruit, on 7-KC-induced apoptosis of human monocyte/macrophage THP-1 cells was investigated. A pathophysiological condition was simulated by using amounts of 7-KC that can be reached in human atheromatous plaque. Ind was assayed within a micromolar concentration range, consistent with its plasma level after dietary supplementation with cactus pear fruit. Pro-apoptotic effects of 7-KC were assessed by cell cycle arrest, exposure of phosphatidylserine at the plasma membrane, variation of nuclear morphology, decrease of mitochondrial trans-membrane potential, activation of Bcl-2 antagonist of cell death and poly(ADP-ribose) polymerase-1 cleavage. Kinetic measurements within 24 h showed early formation of intracellular reactive oxygen species over basal levels, preceding NADPH oxidase-4 (NOX-4) over-expression and elevation of cytosolic Ca²âº, with progressive depletion of total thiols. 7-KC-dependent activation of the redox-sensitive NF-κB was observed. Co-incubation of 2·5 µm of Ind completely prevented 7-KC-induced pro-apoptotic events. The effects of Ind may be ascribed to inhibition of NOX-4 basal activity and over-expression, inhibition of NF-κB activation, maintaining cell redox balance and Ca homeostasis, with prevention of mitochondrial damage and consequently apoptosis. The findings suggest that Ind, a highly bioavailable dietary phytochemical, may exert protective effects against atherogenetic toxicity of 7-KC at a concentration of nutritional interest.


Assuntos
Apoptose/efeitos dos fármacos , Betaxantinas/farmacologia , Cálcio/metabolismo , Cetocolesteróis/efeitos adversos , Opuntia/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Piridinas/farmacologia , Aterosclerose/prevenção & controle , Betaxantinas/sangue , Betaxantinas/uso terapêutico , Linhagem Celular , Citosol/metabolismo , Suplementos Nutricionais , Frutas , Humanos , Cetocolesteróis/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mitocôndrias/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Fitoterapia , Placa Aterosclerótica/prevenção & controle , Piridinas/sangue , Piridinas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/metabolismo
18.
Mem Inst Oswaldo Cruz ; 108 Suppl 1: 80-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24473806

RESUMO

Mosquitoes are the culprits of some of the most important vector borne diseases. A species' potential as a vector is directly dependent on their pattern of behaviour, which is known to change according to the female's physiological status such as whether the female is virgin/mated and unfed/blood-fed. However, the molecular mechanism triggered by and/or responsible for such modulations in behaviour is poorly understood. Clock genes are known to be responsible for the control of circadian behaviour in several species. Here we investigate the impact mating and blood-feeding have upon the expression of these genes in the mosquito Aedes aegypti. We show that blood intake, but not insemination, is responsible for the down-regulation of clock genes. Using RNA interference, we observe a slight reduction in the evening activity peak in the fourth day after dstim injection. These data suggest that, as in Drosophila, clock gene expression, circadian behaviour and environmental light regimens are interconnected in Ae. aegypti.


Assuntos
Aedes/genética , Proteínas CLOCK/genética , Relógios Circadianos/genética , Inseminação/genética , Fotoperíodo , Interferência de RNA/fisiologia , Animais , Ritmo Circadiano/genética , Regulação para Baixo/genética , Comportamento Alimentar/fisiologia , Feminino , Expressão Gênica , Atividade Motora/genética , Reação em Cadeia da Polimerase em Tempo Real , Comportamento Sexual Animal
19.
Antioxidants (Basel) ; 12(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37760012

RESUMO

Griffonia simplicifolia, a tropical plant endemic to West Africa, is highly regarded for its significant pharmacological potential. The objective of this study was to evaluate the metabolomic profile and to explore the antioxidant properties, antiproliferative activity, and antimicrobial potential of G. simplicifolia seed extracts obtained through either maceration, microwave-assisted extraction (MAE), or Soxhlet extraction using water, acetone, methanol and ethanol as solvents. Overall, methanol possessed superior total extraction efficiency. HPLC analyses confirmed the efficacy of acetone and ethanol as optimal solvents for the extraction of flavonoids and flavan-3-ols, whereas MAE exhibited enhanced effectiveness in extracting N-containing compounds, including 5-hydroxytryptophan (5-HTP). HPLC-MS analyses identified forty-three compounds, including thirty-four phenolic compounds and nine N-containing molecules. Isomyricitrin, taxifolin and a flavonol glucuronide were the main polyphenols, whereas 5-HTP was the main N-containing compound. Hydroalcoholic G. simplicifolia extracts showed the highest radical scavenging and metal-reducing antioxidant power, suggesting that most of the contribution to antioxidant activity depends on the more polar bioactive compounds. G. simplicifolia extracts showed dose-dependent antiproliferative activity against three distinct cancer cell lines (HeLa, HepG2, and MCF-7), with notable variations observed among both the different extracts and cell lines and divergent GI50 values, emphasizing substantial discrepancies in cell sensitivity to the various extracts. Furthermore, G. simplicifolia extracts revealed antibiotic activity against Staphylococcus aureus. Our results highlight the potential of G. simplicifolia phytochemicals in the development of functional foods, nutraceuticals, and dietary supplements.

20.
Dalton Trans ; 52(10): 2966-2975, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36444991

RESUMO

DNA G-rich sequences can organize in four-stranded structures called G-quadruplexes (G4s). These motifs are enriched in significant sites within the human genomes, including telomeres and promoters of cancer related genes. For instance, KIT proto-oncogene promoter, associated with diverse cancers, contains three adjacent G4 units, namely Kit2, SP, and Kit1. Aiming at finding new and selective G-quadruplex binders, we have synthesized and characterized five non-charged metal complexes of Pt(II), Pd(II), Ni(II), Cu(II) and Zn(II) of a chlorine substituted Salphen ligand. The crystal structure of the Pt(II) and Pd(II) complexes was determined by XRPD. FRET measurements indicated that Pt(II) and Pd(II) compounds stabilize Kit1 and Kit2 G4s but not SP, telomeric and double stranded DNA. Spectroscopic investigations (UV-Vis, circular dichroism and fluorescence) suggested the Cu(II) complex as the most G4-selective compound. Interestingly, docking simulations indicate that the synthesized compounds fit groove binding pockets of both Kit1 and Kit2 G4s. Moreover, they exhibited dose-dependent cytotoxic activity in MCF-7, HepG2 and HeLa cancer cells.


Assuntos
Antineoplásicos , Complexos de Coordenação , Quadruplex G , Humanos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Antineoplásicos/farmacologia , Fenilenodiaminas/química , Dicroísmo Circular , Telômero
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