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1.
Methods Mol Biol ; 2265: 591-620, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704742

RESUMO

Melanoma accounts for 4% of all skin cancer malignancies, with only 14% of diagnosed patients surviving for more than 5 years after diagnosis. Until now, there is no clear understanding of the detailed molecular contributors of melanoma pathogenesis. Accordingly, more research is needed to understand melanoma development and prognosis.All the treatment approaches that are currently applied have several significant limitations that prevent effective use in melanoma. One major limitation in the treatment of cancer is the acquisition of multidrug resistance (MDR). The MDR results in significant treatment failure and poor clinical outcomes in several cancers, including skin cancer. Treatment of melanoma is especially retarded by MDR. Despite the current advances in targeted and immune-mediated therapy, treatment arms of melanoma are severely limited and stand as a significant clinical challenge. Further, the poor pharmacokinetic profile of currently used chemotherapeutic agents is another reason for treatment failure. Therefore, more research is needed to develop novel drugs and carrier tools for more effective and targeted treatment.Nucleic acid therapy is based on nucleic acids or chemical compounds that are closely related, such as antisense oligonucleotides, aptamers, and small-interfering RNAs that are usually used in situations when a specific gene implicated in a disorder is deemed a therapeutically beneficial target for inhibition. However, the proper application for nucleic acid therapies is hampered by the development of an effective delivery system that can maintain their stability in the systemic circulation and enhance their uptake by the target cells. In this chapter, the prognosis of the different types of melanoma along with the currently used medications is highlighted, and the different types of nucleic acids along with the currently available nanoparticle systems for delivering these nucleic acids into melanoma cells are discussed. We also discuss recently conducted research on the use of different types of nanoparticles for nucleic acid delivery into melanoma cells and highlight the most significant outcomes.


Assuntos
Antineoplásicos , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Melanoma/tratamento farmacológico , Nanopartículas , Ácidos Nucleicos , Neoplasias Cutâneas/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Ácidos Nucleicos/química , Ácidos Nucleicos/farmacologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
2.
Anal Chem ; 93(4): 2351-2358, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33427441

RESUMO

Polymerase chain reaction (PCR) is by far the most commonly used method of nucleic acid amplification and has likewise been employed for a plethora of diagnostic purposes. Nonetheless, multiplexed PCR-based detection schemes have hitherto been largely limited by technical challenges associated with nonspecific interactions and other limitations inherent to traditional fluorescence-based assays. Here, we describe a novel strategy for multiplexed PCR-based analysis called Ligation-eNabled fluorescence-Coding PCR (LiNC PCR) that exponentially enhances the multiplexing capability of standard fluorescence-based PCR assays. The technique relies upon a simple, preliminary ligation reaction in which target DNA sequences are converted to PCR template molecules with distinct endpoint fluorescence signatures. Universal TaqMan probes are used to create target-specific multicolor fluorescence signals that can be readily decoded to identify amplified targets of interest. We demonstrate the LiNC PCR technique by implementing a two-color-based assay for detection of 10 ovarian cancer epigenetic biomarkers at analytical sensitivities as low as 60 template molecules with no detectable target cross-talk. Overall, LiNC PCR provides a simple and inexpensive method for achieving high-dimensional multiplexing that can be implemented in manifold molecular diagnostic applications.


Assuntos
Fluorescência , Ácidos Nucleicos/química , Reação em Cadeia da Polimerase/métodos , Sequência de Bases
3.
Anal Chem ; 93(2): 812-819, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33395261

RESUMO

Electrochemical impedance spectroscopy (EIS), an extremely sensitive analytical technique, is a widely used signal transduction method for the electrochemical detection of target analytes in a broad range of applications. The use of nucleic acids (aptamers) for sequence-specific or molecular detection in electrochemical biosensor development has been extensive, and the field continues to grow. Although nucleic acid-based sensors using EIS offer exceptional sensitivity, signal fidelity is often linked to the physical and chemical properties of the electrode-solution interface. Little emphasis has been placed on the stability of nucleic acid self-assembled monolayers (SAMs) over repeated voltammetric and impedimetric analyses. We have studied the stability and performance of electrochemical biosensors with mixed SAMs of varying length thiolated nucleic acids and short mercapto alcohols on gold surfaces under repeated electrochemical interrogation. This systematic study demonstrates that signal fidelity is linked to the stability of the SAM layer and nucleic acid structure and the packing density of the nucleic acid on the surface. A decrease in packing density and structural changes of nucleic acids significantly influence the signal change observed with EIS after routine voltammetric analysis. The goal of this article is to improve our understanding of the effect of multiple factors on EIS signal response and to optimize the experimental conditions for development of sensitive and reproducible sensors. Our data demonstrate a need for rigorous control experiments to ensure that the measured change in impedance is unequivocally a result of a specific interaction between the target analyte and nucleic recognition element.


Assuntos
Impedância Elétrica , Ácidos Nucleicos/química , Aptâmeros de Nucleotídeos/química , DNA , Espectroscopia Dielétrica/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Transdução de Sinais
4.
Nat Commun ; 12(1): 501, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479249

RESUMO

DNA-PAINT is a versatile optical super-resolution technique relying on the transient binding of fluorescent DNA 'imagers' to target epitopes. Its performance in biological samples is often constrained by strong background signals and non-specific binding events, both exacerbated by high imager concentrations. Here we describe Repeat DNA-PAINT, a method that enables a substantial reduction in imager concentration, thus suppressing spurious signals. Additionally, Repeat DNA-PAINT reduces photoinduced target-site loss and can accelerate sampling, all without affecting spatial resolution.


Assuntos
DNA/química , Microscopia de Fluorescência/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Animais , Ácidos Nucleicos/química , Oligonucleotídeos/química , Reprodutibilidade dos Testes
5.
Nucleic Acids Res ; 49(3): 1201-1234, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33476366

RESUMO

Operations with nucleic acids are among the main means of studying the mechanisms of gene function and developing novel methods of molecular medicine and gene therapy. These endeavours usually imply the necessity of nucleic acid storage and delivery into eukaryotic cells. In spite of diversity of the existing dedicated techniques, all of them have their limitations. Thus, a recent notion of using ionic liquids in manipulations of nucleic acids has been attracting significant attention lately. Due to their unique physicochemical properties, in particular, their micro-structuring impact and tunability, ionic liquids are currently applied as solvents and stabilizing media in chemical synthesis, electrochemistry, biotechnology, and other areas. Here, we review the current knowledge on interactions between nucleic acids and ionic liquids and discuss potential advantages of applying the latter in delivery of the former into eukaryotic cells.


Assuntos
Técnicas de Transferência de Genes , Líquidos Iônicos/química , Ácidos Nucleicos , Células Eucarióticas , Ácidos Nucleicos/química
6.
Methods Mol Biol ; 2170: 45-51, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32797450

RESUMO

Northern blotting is a classical technique that allows the detection of specific nucleic acids using radioactive or non-radioactive probes. Normally, nucleic acids are denatured and separated by agarose or polyacrylamide gel electrophoresis and transferred and fixed to a membrane prior to detection. Here, we describe a method to analyze specific RNA in native ribonucleoprotein complexes using blue native PAGE with subsequent northern blotting, crosslinking of RNA onto a suitable membrane, and detection using non-radioactive probes.


Assuntos
Northern Blotting/métodos , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , RNA/química , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Ácidos Nucleicos/química , Ácidos Nucleicos/metabolismo
7.
Methods Mol Biol ; 2178: 251-284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33128755

RESUMO

Nowadays, monolithic stationary phases, because of their special morphology and enormous permeability, are widely used for the development and realization of fast dynamic and static processes based on the mass transition between liquid and solid phases. These are liquid chromatography, solid-phase synthesis, microarrays, flow-through enzyme reactors, etc. High-performance liquid chromatography on monoliths, including the bioaffinity mode, represents unique technique appropriate for fast and efficient separation of biological (macro)molecules of different sizes and shapes (proteins, nucleic acids, peptides), as well as such supramolecular systems as viruses.In the edited chapter, the examples of the application of commercially available macroporous monoliths for modern affinity processing are presented. In particular, the original methods developed for efficient isolation and fractionation of monospecific antibodies from rabbit blood sera, the possibility of simultaneous affinity separation of protein G and serum albumin from human serum, the isolation of recombinant products, such as protein G and tissue plasminogen activator, respectively, are described in detail. The suggested and realized multifunctional fractionation of polyclonal pools of antibodies by the combination of several short monolithic columns (disks) with different affinity functionalities stacked in the same cartridge represents the original and practically valuable method that can be used in biotechnology. In addition, macroporous monoliths were adapted to the immobilization of such different enzymes as polynucleotide phosphorylase, ribonuclease A, α-chymotrypsin, chitinolytic biocatalysts, ß-xylosidase, and ß-xylanase. The possibility of use of immobilized enzyme reactors based on monoliths for different purposes is demonstrated.


Assuntos
Anticorpos , Ácidos Nucleicos , Peptídeos , Vírus , Anticorpos/química , Anticorpos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ácidos Nucleicos/química , Ácidos Nucleicos/isolamento & purificação , Peptídeos/química , Peptídeos/isolamento & purificação , Vírus/química , Vírus/isolamento & purificação
8.
Methods Mol Biol ; 2211: 43-55, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33336269

RESUMO

The assessment of the efficient binding between a nucleic acid and its associated nanoparticle is crucial for gene delivery. Emerging from the extensive search for versatile gene carriers, are complexes formed between nucleic acids and nonviral nanocarriers that promise to be viable alternatives to the predominantly viral-based gene delivery vehicles. However, much is still to be known about the exact structure and physico-chemical properties of such nanocomplexes. This chapter will concentrate on cationic lipid, polymer, and functionalized metal nanoparticles and their interaction with nucleic acids by direct conjugation or electrostatic interaction. Methods commonly employed to evaluate the nature and extent of nucleic acid interactions with cationic nanocarriers, such a nucleic acid binding, nuclease protection, and dye displacement assays will be described. In addition, the ultrastructural morphology, size, and zeta potential of these nanocomplexes, which are crucial for their cellular uptake and intracellular trafficking, will be assessed using electron microscopy, fluorescent detection, and nanoparticle tracking analysis (NTA). These assays have the ability to visualize and quantify the interaction and can also be used to complement each other, in addition to providing confirmation of the formation of the relevant nanocomplexes.


Assuntos
Cátions/química , Técnicas de Transferência de Genes , Nanopartículas/química , Ácidos Nucleicos/administração & dosagem , Ácidos Nucleicos/química , Linhagem Celular , Células Cultivadas , Expressão Gênica , Genes Reporter , Humanos
9.
Int J Mol Sci ; 21(24)2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33322664

RESUMO

Supramolecular architectures that are built artificially from biomolecules, such as nucleic acids or peptides, with structural hierarchical orders ranging from the molecular to nano-scales have attracted increased attention in molecular science research fields. The engineering of nanostructures with such biomolecule-based supramolecular architectures could offer an opportunity for the development of biocompatible supramolecular (nano)materials. In this review, we highlighted a variety of supramolecular architectures that were assembled from both nucleic acids and peptides through the non-covalent interactions between them or the covalently conjugated molecular hybrids between them.


Assuntos
Nanoestruturas/química , Nanotecnologia/métodos , Ácidos Nucleicos/química , Ácidos Nucleicos Peptídicos/química , Peptídeos/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Ácidos Nucleicos/ultraestrutura , Ácidos Nucleicos Peptídicos/ultraestrutura , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
10.
Int J Nanomedicine ; 15: 6917-6934, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061359

RESUMO

Exosomes are nano-sized small extracellular vesicles secreted by cells, carrying nucleic acids, proteins, lipids and other bioactive substances to play a role in the body's physiological and pathological processes. Compared to synthetic carriers such as liposomes and nanoparticles, the endogeneity and heterogeneity of exosomes give them extensive and unique advantages in the field of disease diagnosis and treatment. However, the storage stability, low yield, low purity, and weak targeting of exosomes limit its clinical application. For this reason, further exploration is needed to optimize the above problems and facilitate future functional studies of exosomes. In this paper, the origin, classification, preparation and characterization, storage stability and applications of exosome delivery system are summarized and discussed by searching a large number of literatures.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Exossomos , Biologia Molecular/métodos , Terapia de Alvo Molecular/métodos , Criopreservação , Exossomos/química , Exossomos/metabolismo , Exossomos/transplante , Alimentos , Liofilização , Humanos , Ácidos Nucleicos/química , Ácidos Nucleicos/metabolismo , Proteínas/química , Proteínas/metabolismo
11.
Nat Commun ; 11(1): 5317, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087707

RESUMO

Multidimensional TOCSY and NOESY are central experiments in chemical and biophysical NMR. Limited efficiencies are an intrinsic downside of these methods, particularly when targeting labile sites. This study demonstrates that the decoherence imparted on these protons through solvent exchanges can, when suitably manipulated, lead to dramatic sensitivity gains per unit time in the acquisition of these experiments. To achieve this, a priori selected frequencies are encoded according to Hadamard recipes, while concurrently subject to looped selective inversion or selective saturation procedures. Suitable processing then leads to protein, oligosaccharide and nucleic acid cross-peak enhancements of ≈200-1000% per scan, in measurements that are ≈10-fold faster than conventional counterparts. The extent of these gains will depend on the solvent exchange and relaxation rates of the targeted sites; these gains also benefit considerably from the spectral resolution provided by ultrahigh fields, as corroborated by NMR experiments at 600 MHz and 1 GHz. The mechanisms underlying these experiments' enhanced efficiencies are analyzed on the basis of three-way polarization transfer interplays between the water, labile and non-labile protons, and the experimental results are rationalized using both analytical and numerical derivations. Limitations as well as further extensions of the proposed methods, are also discussed.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Ácidos Nucleicos/química , Polissacarídeos/química , Proteínas/química , Sítios de Ligação , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular/métodos
13.
Phys Chem Chem Phys ; 22(20): 11197-11218, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32393957

RESUMO

Compartmentalization is a fundamental principle in biology that is needed for the temporal and spatial separation of chemically incompatible reactions and biomolecules. Nano- or micro-sized compartments made of synthetic polymers are used to mimick this principle. The self-assembly of these polymers into vesicular objects is highly compatible with the integration of biomolecules, either into the lumen, the membrane or onto the surface of the vesicles. Thus, a great variety of biohybrid nano- and microscaled compartments has been developed exploiting the specific function and properties of targeting peptides, antibodies, enzymes, nucleic acids or lipids. Such biohybrid compartments have moved from simple systems encapsulating e.g. a model protein into complex multicompartmentalized structures that are able to combine the activity of different biomolecular cargos getting closer to the realization of artifical organelles or cells. Encapsulation of medically relevant cargos combined with careful design of the polymeric scaffold and specific surface functionalization have led to a significant progress in therapeutical applications such as targeted drug delivery or enzyme replacement therapy.


Assuntos
Células Artificiais/química , Polímeros/química , Ácidos Nucleicos/química , Peptídeos/química , Proteínas/química , Lipossomas Unilamelares/química
14.
Nucleic Acids Res ; 48(W1): W94-W103, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32427333

RESUMO

A mixed Protein Structure Network (PSN) and Elastic Network Model-Normal Mode Analysis (ENM-NMA)-based strategy (i.e. PSN-ENM) was developed to investigate structural communication in bio-macromolecules. Protein Structure Graphs (PSGs) are computed on a single structure, whereas information on system dynamics is supplied by ENM-NMA. The approach was implemented in a webserver (webPSN), which was significantly updated herein. The webserver now handles both proteins and nucleic acids and relies on an internal upgradable database of network parameters for ions and small molecules in all PDB structures. Apart from the radical restyle of the server and some changes in the calculation setup, other major novelties concern the possibility to: a) compute the differences in nodes, links, and communication pathways between two structures (i.e. network difference) and b) infer links, hubs, communities, and metapaths from consensus networks computed on a number of structures. These new features are useful to identify commonalties and differences between two different functional states of the same system or structural-communication signatures in homologous or analogous systems. The output analysis relies on 3D-representations, interactive tables and graphs, also available for download. Speed and accuracy make this server suitable to comparatively investigate structural communication in large sets of bio-macromolecular systems. URL: http://webpsn.hpc.unimore.it.


Assuntos
Conformação Proteica , Software , Internet , Modelos Moleculares , Conformação de Ácido Nucleico , Ácidos Nucleicos/química , Proteínas/química
15.
Nucleic Acids Res ; 48(13): e74, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32442277

RESUMO

Sophisticated analysis and simplified visualization are crucial for understanding complicated structures of biomacromolecules. DSSR (Dissecting the Spatial Structure of RNA) is an integrated computational tool that has streamlined the analysis and annotation of 3D nucleic acid structures. The program creates schematic block representations in diverse styles that can be seamlessly integrated into PyMOL and complement its other popular visualization options. In addition to portraying individual base blocks, DSSR can draw Watson-Crick pairs as long blocks and highlight the minor-groove edges. Notably, DSSR can dramatically simplify the depiction of G-quadruplexes by automatically detecting G-tetrads and treating them as large square blocks. The DSSR-enabled innovative schematics with PyMOL are aesthetically pleasing and highly informative: the base identity, pairing geometry, stacking interactions, double-helical stems, and G-quadruplexes are immediately obvious. These features can be accessed via four interfaces: the command-line interface, the DSSR plugin for PyMOL, the web application, and the web application programming interface. The supplemental PDF serves as a practical guide, with complete and reproducible examples. Thus, even beginners or occasional users can get started quickly, especially via the web application at http://skmatic.x3dna.org.


Assuntos
Conformação de Ácido Nucleico , Ácidos Nucleicos/química , Software , Modelos Moleculares
16.
Acta Crystallogr C Struct Chem ; 76(Pt 5): 513-523, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32367834

RESUMO

The positional change of nitrogen-7 of the RNA constituent guanosine to the bridgehead position-5 leads to the base-modified nucleoside 5-aza-7-deazaguanosine. Contrary to guanosine, this molecule cannot form Hoogsteen base pairs and the Watson-Crick proton donor site N3-H becomes a proton-acceptor site. This causes changes in nucleobase recognition in nucleic acids and has been used to construct stable `all-purine' DNA and DNA with silver-mediated base pairs. The present work reports the single-crystal X-ray structure of 7-iodo-5-aza-7-deazaguanosine, C10H12IN5O5 (1). The iodinated nucleoside shows an anti conformation at the glycosylic bond and an N conformation (O4'-endo) for the ribose moiety, with an antiperiplanar orientation of the 5'-hydroxy group. Crystal packing is controlled by interactions between nucleobase and sugar moieties. The 7-iodo substituent forms a contact to oxygen-2' of the ribose moiety. Self-pairing of the nucleobases does not take place. A Hirshfeld surface analysis of 1 highlights the contacts of the nucleobase and sugar moiety (O-H...O and N-H...O). The concept of pK-value differences to evaluate base-pair stability was applied to purine-purine base pairing and stable base pairs were predicted for the construction of `all-purine' RNA. Furthermore, the 7-iodo substituent of 1 was functionalized with benzofuran to detect motional constraints by fluorescence spectroscopy.


Assuntos
DNA/química , Guanosina/análogos & derivados , Ácidos Nucleicos/química , Purinas/química , Ribonucleosídeos/química , Prata/química , Pareamento de Bases , Cristalografia por Raios X , Guanosina/química , Conformação Molecular
17.
Int J Nanomedicine ; 15: 2809-2828, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368056

RESUMO

Introduction: Glioblastoma (GBM) is the most common and lethal of the central nervous system (CNS) malignancies. The initiation, progression, and infiltration ability of GBMs are attributed in part to the dysregulation of microRNAs (miRNAs). Thus, targeting dysregulated miRNAs with RNA oligonucleotides (RNA interference, RNAi) has been proposed for GBM treatment. Despite promising results in the laboratory, RNA oligonucleotides have clinical limitations that include poor RNA stability and off-target effects. RNAi therapies against GBM confront an additional obstacle, as they need to cross the blood-brain barrier (BBB). Methods: Here, we developed gold-liposome nanoparticles conjugated with the brain targeting peptides apolipoprotein E (ApoE) and rabies virus glycoprotein (RVG). First, we functionalized gold nanoparticles with oligonucleotide miRNA inhibitors (OMIs), creating spherical nucleic acids (SNAs). Next, we encapsulated SNAs into ApoE, or RVG-conjugated liposomes, to obtain SNA-Liposome-ApoE and SNA-Liposome-RVG, respectively. We characterized each nanoparticle in terms of their size, charge, encapsulation efficiency, and delivery efficiency into U87 GBM cells in vitro. Then, they were administered intravenously (iv) in GBM syngeneic mice to evaluate their delivery efficiency to brain tumor tissue. Results: SNA-Liposomes of about 30-50 nm in diameter internalized U87 GBM cells and inhibited the expression of miRNA-92b, an aberrantly overexpressed miRNA in GBM cell lines and GBM tumors. Conjugating SNA-Liposomes with ApoE or RVG peptides increased their systemic delivery to the brain tumors of GBM syngeneic mice. SNA-Liposome-ApoE demonstrated to accumulate at higher extension in brain tumor tissues, when compared with non-treated controls, SNA-Liposomes, or SNA-Liposome-RVG. Discussion: SNA-Liposome-ApoE has the potential to advance the translation of miRNA-based therapies for GBM as well as other CNS disorders.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Lipossomos/administração & dosagem , Interferência de RNA , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Técnicas de Transferência de Genes , Glioblastoma/genética , Glioblastoma/patologia , Ouro/química , Humanos , Lipossomos/química , Masculino , Nanopartículas Metálicas/química , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Ácidos Nucleicos/química , Oligonucleotídeos/química , Oligonucleotídeos/genética , Oligonucleotídeos/farmacocinética , Proteínas do Envelope Viral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
18.
ACS Appl Mater Interfaces ; 12(10): 11397-11408, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32083455

RESUMO

Currently available strategies show limited effects in preventing morbidity and disability from chronic diabetic wounds. Ideal vascularization is indispensable for better restoration and prognosis of diabetic wounds. This study aims to investigate the role of tetrahedral framework nucleic acids (tFNAs) in the process of angiogenesis during diabetic wound healing and the underlying mechanism. The in vitro results showed that tFNAs treatment enhanced the formation of a vessel-like structure that was inhibited by advanced glycation end products (AGEs). Positive variations were detected in aspects of cell viability, migratory ability, nitric oxide (NO) levels, and vascular endothelial growth factor-A (VEGF-A) expression. In addition, high reactive oxygen species (ROS) levels and gene expressions relevant to oxidative damage and inflammation in diabetic human umbilical vein endothelial cells (HUVECs) were attenuated by tFNAs. As for the underlying mechanism, the p-Akt/total Akt ratio, nuclear factor erythroid 2-related factor 2 (Nrf2) levels, and heme oxygenase-1 (HO-1) levels were higher in diabetic HUVECs treated with tFNAs. In vivo experiments showed that tFNAs facilitated diabetic wound healing by accelerating vascularization, epithelialization, collagen deposition, and collagen alignment. In conclusion, tFNAs could protect endothelial cell function, reduce inflammation, and impede oxidative damage through their antioxidant activity via the Akt/Nrf2/HO-1 signaling pathway. The application of tFNAs may pave the way for better healing of diabetic wounds.


Assuntos
Indutores da Angiogênese/farmacologia , Antioxidantes/farmacologia , Ácidos Nucleicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/química , Animais , Antioxidantes/química , Células Cultivadas , Pé Diabético/metabolismo , Modelos Animais de Doenças , Produtos Finais de Glicação Avançada/metabolismo , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Nanoestruturas/química , Ácidos Nucleicos/química , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
19.
Top Curr Chem (Cham) ; 378(2): 26, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32067108

RESUMO

Genetic information and the blueprint of life are stored in the form of nucleic acids. The primary sequence of DNA, read from the canonical double helix, provides the code for RNA and protein synthesis. Yet these already-information-rich molecules have higher-order structures which play critical roles in transcription and translation. Uncovering the sequences, parameters, and conditions which govern the formation of these structural motifs has allowed researchers to study them and to utilize them in biotechnological and therapeutic applications in vitro and in vivo. This review covers both DNA and RNA structural motifs found naturally in biological systems including catalytic nucleic acids, non-coding RNA, aptamers, G-quadruplexes, i-motifs, and Holliday junctions. For each category, an overview of the structural characteristics, biological prevalence, and function will be discussed. The biotechnological and therapeutic applications of these structural motifs are highlighted. Future perspectives focus on the addition of proteins and unnatural modifications to enhance structural stability for greater applicability.


Assuntos
Biotecnologia , Ácidos Nucleicos/química , Ácidos Nucleicos/uso terapêutico , Conformação de Ácido Nucleico
20.
Molecules ; 25(3)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012929

RESUMO

Antibiotic resistance is an escalating, worldwide problem. Due to excessive use of antibiotics, multidrug-resistant bacteria have become a serious threat and a major global healthcare problem of the 21st century. This fact creates an urgent need for new and effective antimicrobials. The common strategies for antibiotic discovery are based on either modifying existing antibiotics or screening compound libraries, but these strategies have not been successful in recent decades. An alternative approach could be to use gene-specific oligonucleotides, such as peptide nucleic acid (PNA) oligomers, that can specifically target any single pathogen. This approach broadens the range of potential targets to any gene with a known sequence in any bacterium, and could significantly reduce the time required to discover new antimicrobials or their redesign, if resistance arises. We review the potential of PNA as an antibacterial molecule. First, we describe the physicochemical properties of PNA and modifications of the PNA backbone and nucleobases. Second, we review the carriers used to transport PNA to bacterial cells. Furthermore, we discuss the PNA targets in antibacterial studies focusing on antisense PNA targeting bacterial mRNA and rRNA.


Assuntos
Antibacterianos/farmacologia , Ácidos Nucleicos Peptídicos/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/química , Bactérias/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Testes de Sensibilidade Microbiana , Conformação de Ácido Nucleico , Ácidos Nucleicos/química , Ácidos Nucleicos Peptídicos/administração & dosagem , Ácidos Nucleicos Peptídicos/química
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