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1.
Pharmaceutics ; 16(6)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38931902

RESUMO

Glioblastoma multiform (GBM) is considered the deadliest brain cancer. Conventional therapies are followed by poor patient survival outcomes, so novel and more efficacious therapeutic strategies are imperative to tackle this scourge. Gene therapy has emerged as an exciting and innovative tool in cancer therapy. Its combination with chemotherapy has significantly improved therapeutic outcomes. In line with this, our team has developed temozolomide-transferrin (Tf) peptide (WRAP5)/p53 gene nanometric complexes that were revealed to be biocompatible with non-cancerous cells and in a zebrafish model and were able to efficiently target and internalize into SNB19 and U373 glioma cell lines. The transfection of these cells, mediated by the formulated peptide-drug/gene complexes, resulted in p53 expression. The combined action of the anticancer drug with p53 supplementation in cancer cells enhances cytotoxicity, which was correlated to apoptosis activation through quantification of caspase-3 activity. In addition, increased caspase-9 levels revealed that the intrinsic or mitochondrial pathway of apoptosis was implicated. This assumption was further evidenced by the presence, in glioma cells, of Bax protein overexpression-a core regulator of this apoptotic pathway. Our findings demonstrated the great potential of peptide TMZ/p53 co-delivery complexes for cellular transfection, p53 expression, and apoptosis induction, holding promising therapeutic value toward glioblastoma.

2.
J Funct Biomater ; 14(7)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37504857

RESUMO

The circadian clock controls behavior and physiology. Presently, there is clear evidence of a connection between this timing system and cancer development/progression. Moreover, circadian rhythm consideration in the therapeutic action of anticancer drugs can enhance the effectiveness of cancer therapy. Nanosized drug delivery systems (DDS) have been demonstrated to be suitable engineered platforms for drug targeted/sustained release. The investigation of the chronobiology-nanotechnology relationship, i.e., timing DDS performance according to a patient's circadian rhythm, may greatly improve cancer clinical outcomes. In the present work, we synthesized nanosystems based on an octa-arginine (R8)-modified poly(amidoamine) dendrimer conjugated with the anticancer drug paclitaxel (PTX), G4-PTX-R8, and its physicochemical properties were revealed to be appropriate for in vitro delivery. The influence of the circadian rhythm on its cellular internalization efficiency and potential therapeutic effect on human cervical cancer cells (HeLa) was studied. Cell-internalized PTX and caspase activity, as a measure of induced apoptosis, were monitored for six time points. Higher levels of PTX and caspase-3/9 were detected at T8, suggesting that the internalization of G4-PTX-R8 into HeLa cells and apoptosis are time-specific/-regulated phenomena. For a deeper understanding, the clock protein Bmal1-the main regulator of rhythmic activity, was silenced by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology. Bmal1 silencing was revealed to have an impact on both PTX release and caspase activity, evidencing a potential role for circadian rhythm on drug delivery/therapeutic effect mediated by G4-PTX-R8.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37107868

RESUMO

Roasting is responsible for imparting the main characteristics to coffee, but the high temperatures used in the process can lead to the formation of several potentially toxic substances. Among them, polycyclic aromatic hydrocarbons, acrylamide, furan and its derivative compounds, α-dicarbonyls and advanced glycation end products, 4-methylimidazole, and chloropropanols stand out. The objective of this review is to present a current and comprehensive overview of the chemical contaminants formed during coffee roasting, including a discussion of mitigation strategies reported in the literature to decrease the concentration of these toxicants. Although the formation of the contaminants occurs during the roasting step, knowledge of the coffee production chain as a whole is important to understand the main variables that will impact their concentrations in the different coffee products. The precursors and routes of formation are generally different for each contaminant, and the formed concentrations can be quite high for some substances. In addition, the study highlights several mitigation strategies related to decreasing the concentration of precursors, modifying process conditions and eliminating/degrading the formed contaminant. Many of these strategies show promising results, but there are still challenges to be overcome, since little information is available about advantages and disadvantages in relation to aspects such as costs, potential for application on an industrial scale and impacts on sensory properties.


Assuntos
Produtos Finais de Glicação Avançada , Hidrocarbonetos Policíclicos Aromáticos , Substâncias Perigosas , Temperatura Alta , Acrilamida/química
4.
Pharmaceutics ; 14(10)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36297647

RESUMO

Despite the great progress over the past few decades in both the diagnosis and treatment of a great variety of human cancers, glioblastoma remains the most lethal brain tumor. In recent years, cancer gene therapy focused on non-viral vectors which emerged as a promising approach to glioblastoma treatment. Transferrin (Tf) easily penetrates brain cells of the blood-brain barrier, and its receptor is highly expressed in this barrier and glioblastoma cells. Therefore, the development of delivery systems containing Tf appears as a reliable strategy to improve their brain cells targeting ability and cellular uptake. In this work, a cell-penetrating peptide (WRAP5), bearing a Tf-targeting sequence, has been exploited to condense tumor suppressor p53-encoding plasmid DNA (pDNA) for the development of nanocomplexes. To increase the functionality of developed nanocomplexes, the drug Temozolomide (TMZ) was also incorporated into the formulations. The physicochemical properties of peptide/pDNA complexes were revealed to be dependent on the nitrogen to phosphate groups ratio and can be optimized to promote efficient cellular internalization. A confocal microscopy study showed the capacity of developed complexes for efficient glioblastoma cell transfection and consequent pDNA delivery into the nucleus, where efficient gene expression took place, followed by p53 protein production. Of promise, these peptide/pDNA complexes induced a significant decrease in the viability of glioblastoma cells. The set of data reported significantly support further in vitro research to evaluate the therapeutic potential of developed complexes against glioblastoma.

5.
Polymers (Basel) ; 14(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35215593

RESUMO

The conception of novel anticancer delivery systems and the combination of chronobiology with nanotechnology may provide a powerful tool to optimize cancer therapy. In this work, polyethylenimine (PEI) has been used to complex p53 encoded plasmid DNA (pDNA), and the anticancer drug methotrexate (MTX) has also been loaded into the vectors. To investigate the influence of circadian clock on drug/gene delivery efficiency, HeLa, C33A and fibroblast cells have been transfected with developed PEI/pDNA/MTX delivery vectors at six different time points. Phenomena as the cellular uptake/internalization, drug/gene delivery and p53 protein production have been evaluated. The cell-associated MTX fluorescence have been monitored, and p53 protein levels quantified. In HeLa and C33A cancer cells, significant levels of MTX were found for T8 and T12. For these time points, a high amount of p53 protein was quantified. Confocal microscopy images showed successful HeLa cell's uptake of PEI/pDNA/MTX particles, at T8. In comparison, poor levels of MTX and p53 protein were found in fibroblasts; nevertheless, results indicated rhythmicity. Data demonstrate the influence of circadian rhythm on both cancer-cells targeting ability and transfection performance of PEI/pDNA/MTX carriers and seemed to provide the optimum time for drug/gene delivery. This report adds a great contribution to the field of cancer chronobiology, highlighting the relationship between circadian rhythm and nanodelivery systems, and charting the path for further research on a, yet, poorly explored but promising topic.

6.
Pharmaceutics ; 13(8)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34452218

RESUMO

Cancer gene therapy, mediated by non-viral systems, remains a major research focus. To contribute to this field, in this work we reported on the development of dendrimer drug/gene ternary complexes. This innovative approach explored the great capacity of both polyamidoamine (PAMAM)-paclitaxel (PTX) conjugate and polyethylenimine (PEI) polymers to complex a p53-encoding plasmid DNA (pDNA), highlighting the utility of considering two compacting agents. The pDNA complexation capacity has been investigated as function of the nitrogen to phosphate groups ratio (N/P), which revealed to be a tailoring parameter. The physicochemical properties of the conceived ternary complexes were revealed and were found to be promising for cellular transfection. Furthermore, the formulated co-delivery systems demonstrated to be biocompatible. The ternary systems were able of cellular internalization and payload intracellular release. Confocal microscopy studies showed the co-localization of stained pDNA with the nucleus of cancer cells, after transfection mediated by these carriers. From this achievement, p53 gene expression occurred with the production of protein. Moreover, the activation of caspase-3 indicated apoptosis of cancer cells. This work represents a great progress on the design of dendrimer drug/gene co-delivery systems towards a more efficient cancer therapy. In this way, it instigates further in vitro studies concerning the evaluation of their therapeutic potential, expectedly supported by the synergistic effect, in tumoral cells.

7.
J Mol Med (Berl) ; 99(10): 1349-1371, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34213595

RESUMO

Circadian clock is an impressive timing system responsible for the control of several metabolic, physiological and behavioural processes. Nowadays, the connection between the circadian clock and cancer occurrence and development is consensual. Therefore, the inclusion of circadian timing into cancer therapy may potentially offer a more effective and less toxic approach. This way, chronotherapy has been shown to improve cancer treatment efficacy. Despite this relevant finding, its clinical application is poorly exploited. The conception of novel anticancer drug delivery systems and the combination of chronobiology with nanotechnology may provide a powerful tool to optimize cancer therapy, instigating the incorporation of the circadian timing into clinical practice towards a more personalized drug delivery. This review focuses on the recent advances in the field of cancer chronobiology, on the link between cancer and the disruption of circadian rhythms and on the promising targeted drug nanodelivery approaches aiming the clinical application of cancer chronotherapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/fisiopatologia , Animais , Cronoterapia/métodos , Relógios Circadianos/efeitos dos fármacos , Relógios Circadianos/fisiologia , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Humanos
8.
Pharmaceutics ; 13(5)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067176

RESUMO

DNA vaccines still represent an emergent area of research, giving rise to continuous progress towards several biomedicine demands. The formulation of delivery systems to specifically target mannose receptors, which are overexpressed on antigen presenting cells (APCs), is considered a suitable strategy to improve the DNA vaccine immunogenicity. The present study developed binary and ternary carriers, based on polyethylenimine (PEI), octa-arginine peptide (R8), and mannose ligands, to specifically deliver a minicircle DNA (mcDNA) vaccine to APCs. Systems were prepared at various nitrogen to phosphate group (N/P) ratios and characterized in terms of their morphology, size, surface charge, and complexation capacity. In vitro studies were conducted to assess the biocompatibility, cell internalization ability, and gene expression of formulated carriers. The high charge density and condensing capacity of both PEI and R8 enhance the interaction with the mcDNA, leading to the formation of smaller particles. The addition of PEI polymer to the R8-mannose/mcDNA binary system reduces the size and increases the zeta potential and system stability. Confocal microscopy studies confirmed intracellular localization of targeting systems, resulting in sustained mcDNA uptake. Furthermore, the efficiency of in vitro transfection can be influenced by the presence of R8-mannose, with great implications for gene expression. R8-mannose/PEI/mcDNA ternary systems can be considered valuable tools to instigate further research, aiming for advances in the DNA vaccine field.

9.
Food Chem ; 289: 625-634, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955657

RESUMO

Actinidia deliciosa and A. arguta fruits (kiwifruit and kiwiberry, respectively) are an excellent source of bioactive compounds. The aim of this paper is to valorize the fruits that are not commercialized (e.g. due to inadequate size or physical damage) in infusions and decoctions. The antioxidant activity, the scavenging activity against reactive species, the phenolic profile and the intestinal effects of infusions and decoctions of dehydrated fruits were evaluated and compared. Decoctions presented the highest antioxidant activity and a good ability to capture HOCl and NO. The phenolic composition of A. arguta present quinic acid, cis-caftaric acid and its derivatives, caffeoyl hexoside, luteolin glucuronide, quercetin derivatives and myristin, while A. deliciosa extracts were characterized by the presence of quinic acid, caffeic acid and its derivatives and caffeoyl hexoside. No adverse effects were observed on Caco-2 and HT29-MTX cells. Kiwiberry decoctions showed to be the best option to keep the fruits benefits.


Assuntos
Actinidia/química , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Células CACO-2 , Dessecação , Manipulação de Alimentos , Células HT29 , Humanos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Ácido Quínico/farmacologia
10.
Colloids Surf B Biointerfaces ; 178: 430-438, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30908999

RESUMO

The development of delivery systems based on cell penetrating peptides represents an incredible asset and may deeply contribute for the evolution of therapies efficacy. In this context, we explore the plasmid DNA (pDNA) condensation ability of TAT peptide to produce a suitable intracellular delivery platform. The nanoparticles were formed at various ratios of nitrogen to phosphate groups (N/P) and the variation of polyplexes properties with this parameter was studied. Beyond the large size exhibited by these carriers, their low pDNA immobilization profile instigates the need for an additional compacting agent. To maximize the performance of this peptide delivery system, a series of alkyl trimethyl ammonium bromide surfactants (CnTAB) were employed to further condense pDNA. In general, not only this strategy promotes the formation of lower sized vectors, but also greatly enhances particle characteristics such as surface charge and pDNA encapsulation. The magnitude of this effect is intimately dependent on surfactant chain length. Furthermore, the known cytotoxicity of cationic surfactants has been dramatically reduced by their incorporation into TAT/pDNA complexes. The release kinetics can be tailored and optimized to promote the controlled/sustained release of pDNA. Following this, the surfactant alkyl chain length and the N/P ratio are important controlling parameters. In addition, doxorubicin and paclitaxel can be efficiently loaded and encapsulated into peptide/pDNA/surfactant carriers. The presented platform reveals a great potential for therapeutic payloads loading and controlled release open advanced and new approaches in the design/formulation of innovative biomedical systems towards clinical translation.


Assuntos
Peptídeos/química , Plasmídeos/genética , Tensoativos/química , Peptídeos Penetradores de Células/química , Nanopartículas/química
11.
Food Res Int ; 111: 724-731, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007738

RESUMO

The nutritional composition of Calluna vulgaris flowers as well as the phytochemical profile, antioxidant (DPPH and FRAP assays), antimicrobial and cytotoxic (in human immortalized non-tumorigenic keratinocyte and fibroblasts) activities of aqueous, hydroalcoholic and ethanolic extracts were evaluated. A high content of fiber and carbohydrates (75%) and the prevalence of α-tocopherol as vitamer deserves attention. Linolenic (35%), linoleic (27%) and palmitic (21%) acids were the most abundant fatty acids. Qualitative and quantitative analysis by LC-MS and 1NMR indicated high levels of quercetin, kaempferol and myricetin derivatives as well as procyanidins. The hydro-alcoholic extract displayed the highest antioxidant activity and total phenolics (TPC) and flavonoid contents (TFC). No adverse effects on cells were observed until a concentration of 100 µg/mL and a good antimicrobial activity was reported against S. epidermidis and S. aureus with the hydro-alcoholic extract. The data obtained demonstrated that wild plants like heather, although not being a common nutritional reference, can be used in an alimentary base as a source of bioactive compounds, namely antioxidants.


Assuntos
Calluna/química , Flores/química , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Antibacterianos/análise , Antibacterianos/farmacologia , Antioxidantes/análise , Linhagem Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácidos Graxos/análise , Flavonoides/análise , Sequestradores de Radicais Livres/análise , Humanos , Quempferóis/análise , Testes de Sensibilidade Microbiana , Nutrientes/análise , Fenóis/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Proantocianidinas/análise , Quercetina/análise , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Vitamina E/análise
12.
Chronobiol Int ; 35(2): 270-279, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29172740

RESUMO

The suprachiasmatic nucleus (SCN) of the hypothalamus is considered the master circadian oscillator in mammals. However, extra-SCN structures in the brain also display daily rhythms. Recently, we have demonstrated that the choroid plexus (CP) expresses core clock genes that are subjected to circadian regulation in a sex-dependent manner. By using CP explants cultured from female knock-in mice carrying the Period-luciferase transgene, we show that CP exhibits endogenous circadian rhythms of PERIOD2::LUCIFERASE expression. Furthermore, we demonstrate that estrogen declines following ovariectomy modulates the daily rhythm expression of Bmal1, Per1 and Per2 in female rat CP, corroborating data obtained in experiments where rat CP epithelial cell (CPEC) cultures were incubated with 17ß-estradiol (E2). The molecular mechanism underlying these effects was also investigated, and we provide evidence that the estrogen receptor (ER) mediates the response of clock genes to E2. In conclusion, our study proves that the CP harbors a circadian oscillator that is modulated by estrogens and demonstrates that E2 regulation occurs through an estrogen-receptor-dependent mechanism.


Assuntos
Plexo Corióideo/metabolismo , Ritmo Circadiano/fisiologia , Estrogênios/metabolismo , Proteínas Circadianas Period/metabolismo , Animais , Feminino , Hipotálamo/metabolismo , Luciferases/metabolismo , Camundongos Transgênicos , Neurônios/metabolismo , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiologia
13.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1061-1062: 334-341, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28787651

RESUMO

The deeper understanding of retinal detachment (RD) pathogenesis may improve the visual outcome after surgery. Given the main role of the vitreous in retinal eye diseases, two strategies were explored to identify its proteome in RD. Fractionation techniques such as anion exchange chromatography (IEX) and SDS-PAGE combined with MALDI-TOF/TOF analysis allowed to identify 127 proteins in vitreous of RD patients. From these proteins, 19 were identified using only the IEX fractionation strategy, and 117 using a bidimensional (IEX and SDS-PAGE) fractionation. Of these proteins, 68 had not yet been found in other vitreous proteomic studies. The fractionation with IEX and SDS-PAGE largely improved the number of identified proteins proving that it is crucial to combine several methodologies to cover vitreous proteome.


Assuntos
Proteoma/análise , Proteômica/métodos , Descolamento Retiniano/metabolismo , Corpo Vítreo/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Proteínas do Olho/análise , Proteínas do Olho/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/química , Proteoma/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
J Sci Food Agric ; 95(1): 44-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24852602

RESUMO

BACKGROUND: The industrial processing of pineapple generates a high quantity of by-products. To reduce the environmental impact of these by-products and the inherent cost of their treatment, it is important to characterise and valorise these products, converting them into high added value products. Ultra-violet radiation is one of the main sustainable sanitation techniques for fruits. Since this radiation can induce plant stress which can promote the biosynthesis of bioactive compounds, it is important to evaluate its effect in fruits. RESULTS: The amounts of vitamins (C and E) and carotenoids (α-carotene, ß-carotene, ß-cryptoxanthin, lutein, lycopene, neoxanthin, violaxanthin and zeaxanthin) in pineapple by-products (core and rind) were analysed before and after treatment with UV radiation. All treated and untreated pineapple by-products contained ß-carotene as the main carotenoid (rind, 2537-3225 µg; and core, 960-994 µg 100 g(-1) DW). Pineapple rind also contained lutein (288-297 µg 100 g(-1) DW) and α-carotene (89-126 µg 100 g(-1) DW). CONCLUSION: The results provide evidence of the potential of pineapple by-products as a source of bioactive compounds with antioxidant activity, which can be used by pharmaceutical, cosmetics and food industries. In addition, UV-C was shown to be a treatment that can add nutritional value to pineapple by-products.


Assuntos
Ananas/química , Manipulação de Alimentos/métodos , Irradiação de Alimentos , Frutas/química , Frutas/efeitos da radiação , Antioxidantes/análise , Ácido Ascórbico/análise , Carotenoides/análise , Luteína/análise , Raios Ultravioleta , Vitamina A/análise , Vitamina E/análise , beta Caroteno/análise
15.
Artigo em Inglês | MEDLINE | ID: mdl-24405324

RESUMO

The demand for natural antioxidant active packaging is increasing due to its unquestionable advantages compared with the addition of antioxidants directly to the food. Therefore, the search for antioxidants perceived as natural, namely those that naturally occur in herbs and spices, is a field attracting great interest. In line with this, in the last few years, natural antioxidants such as α-tocopherol, caffeic acid, catechin, quercetin, carvacrol and plant extracts (e.g. rosemary extract) have been incorporated into food packaging. On the other hand, consumers and the food industry are also interested in active biodegradable/compostable packaging and edible films to reduce environmental impact, minimise food loss and minimise contaminants from industrial production and reutilisation by-products. The present review focuses on the natural antioxidants already applied in active food packaging, and it reviews the methods used to determine the oxidation protection effect of antioxidant active films and the methods used to quantify natural antioxidants in food matrices or food simulants. Lastly consumers' demands and industry trends are also addressed.


Assuntos
Antioxidantes/química , Embalagem de Alimentos/tendências , Biodegradação Ambiental , União Europeia , Embalagem de Alimentos/legislação & jurisprudência , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Humanos , Legislação sobre Alimentos , Extratos Vegetais/química
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