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1.
Lasers Med Sci ; 39(1): 75, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383862

RESUMO

The aim of the study was to investigate the impact of multiwave locked system (MLS M1) emitting synchronized laser radiation at 2 wavelength simultaneous (λ = 808 nm, λ = 905 nm) on the mesenchymal stem cells (MSCs). Human MSCs were exposed to MLS M1 system laser radiation with the power density 195-318 mW/cm2 and doses of energy 3-20 J, in continuous wave emission (CW) or pulsed emission (PE). After irradiation exposure in doses of energy 3 J, 10 J (CW, ƒ = 1000 Hz), and 20 J (ƒ = 2000 Hz), increased proliferation of MSCs was observed. Significant reduction of Fluo-4 Direct™ Ca2+ indicator fluorescence over controls after CW and PE with 3 J, 10 J, and 20 J was noticed. A decrease in fluorescence intensity after the application of radiation with a frequency of 2000 Hz in doses of 3 J, 10 J, and 20 J was observed. In contrary, an increase in DCF fluorescence intensity after irradiation with laser radiation of 3 J, 10 J, and 20 J (CW, ƒ = 1000 Hz and ƒ = 2000 Hz) was also shown. Laser irradiation at a dose of 20 J, emitted at 1000 Hz and 2000 Hz, and 3 J emitted at a frequency of 2000 Hz caused a statistically significant loss of MSC viability. The applied photobiomodulation therapy induced a strong pro-apoptotic effect dependent on the laser irradiation exposure time, while the application of a sufficiently high-energy dose and frequency with a sufficiently long exposure time significantly increased intracellular calcium ion concentration and free radical production by MSCs.


Assuntos
Terapia com Luz de Baixa Intensidade , Células-Tronco Mesenquimais , Humanos , Cálcio , Radicais Livres , Apoptose , Necrose , Células-Tronco Mesenquimais/efeitos da radiação
2.
Sci Rep ; 12(1): 1095, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35058528

RESUMO

Plants have served for centuries as sources of compounds useful for human health such as antioxidant, anti-diabetic and antitumor agents. They are also rich in nutrients that improve the human diet. Growing demands for these compounds make it important to seek new sources for them. Hippophae rhamnoides L. is known as a plant with health-promoting properties. In this study we investigated the chemical composition and biological properties of bioactive components of ethanol extracts from leaves and twigs of H. rhamnoides L. Chemical components such as the total content of phenolic compounds, vitamins and amino acids and the antioxidant activities of these compounds in cellular and cell-free systems were assessed. The results suggest that the studied extracts are rich in bioactive compounds with potent antioxidant properties. Cytotoxicity and hemotoxicity assays showed that the extracts had low toxicity on human cells over the range of concentrations tested. Interaction with human serum albumin was investigated and conformational changes were observed. Our results indicate that leaf and twig extracts of H. rhamnoides L. should be considered as a non-toxic source of bioactive compounds which may be of interest to the food, pharmaceutical and cosmetic industries.


Assuntos
Hippophae/metabolismo , Extratos Vegetais/farmacologia , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Etanol/análise , Flavonoides/análise , Frutas/química , Hippophae/química , Testes de Sensibilidade Microbiana , Nutrientes , Fenóis/análise , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Polônia
4.
Lasers Surg Med ; 51(9): 824-833, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31165521

RESUMO

BACKGROUND AND OBJECTIVES: We have investigated how low intensity laser irradiation emitted by a multiwave-locked system (MLS M1) affects the viability and proliferation of human bone marrow mesenchymal stem cells (MSCs) depending on the parameters of the irradiation. STUDY DESIGN/MATERIALS AND METHODS: Cells isolated surgically from the femoral bone during surgery were identified by flow cytometry and cell differentiation assays. For irradiation, two wavelengths (808 and 905 nm) with the following parameters were used: power density 195, 230, and 318 mW/cm 2 , doses of energy 3, 10, and 20 J (energy density 0.93-6.27 J/cm 2 ), and in continuous (CW) or pulsed emission (PE) (frequencies 1,000 and 2,000 Hz). RESULTS: There were statistically significant increases of cell viability and proliferation after irradiation at 3 J (CW; 1,000 Hz), 10 J (1,000 Hz), and 20 J (2,000 Hz). CONCLUSIONS: Irradiation with the MLS M1 system can be used in vitro to modulate MSCs in preparation for therapeutic applications. This will assist in designing further studies to optimize the radiation parameters and elucidate the molecular mechanisms of action of the radiation. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.


Assuntos
Proliferação de Células/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Mesenquimais/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Humanos
5.
Ann Agric Environ Med ; 25(1): 108-113, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29575876

RESUMO

INTRODUCTION: Authors of numerous publications have proved the therapeutic effect of laser irradiation on biological material, but the mechanisms at cellular and subcellular level are not yet well understood. OBJECTIVE: The aim of this study was to assess the effect of laser radiation emitted by the MLS M1 system (Multiwave Locked System) at two wavelengths (808 nm continuous and 905 nm pulsed) on the stability and fluidity of liposomes with a lipid composition similar to that of human erythrocyte membrane or made of phosphatidylocholine. MATERIAL AND METHODS: Liposomes were exposed to low-energy laser radiation at surface densities 195 mW/cm2 (frequency 1,000 Hz) and 230 mW/cm2 (frequency 2,000 Hz). Different doses of radiation energy in the range 0-15 J were applied. The surface energy density was within the range 0.46 - 4.9 J/cm 2. RESULTS: The fluidity and stability of liposomes subjected to such irradiation changed depending on the parameters of radiation used. CONCLUSIONS: Since MLS M1 laser radiation, depending on the parameters used, affects fluidity and stability of liposomes with the lipid content similar to erythrocyte membrane, it may also cause structural and functional changes in cell membranes.


Assuntos
Membrana Celular/efeitos da radiação , Lipídeos de Membrana/efeitos da radiação , Eritrócitos/efeitos da radiação , Humanos , Lasers , Lipossomos/química , Lipossomos/efeitos da radiação , Terapia com Luz de Baixa Intensidade/instrumentação , Fluidez de Membrana/efeitos da radiação
6.
Mol Pharm ; 14(11): 4087-4097, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28960997

RESUMO

Original metallophosphorus dendrimers (generation 3, 48 terminal groups) have been prepared via the complexation of phosphorus dendrimers bearing imino-pyridino end groups with Au(III) or with both Au(III) and Cu(II). The complexation of the dendrimer with Au(III), leading to 1G3-[Au48][AuCl4]48, strongly increased the antiproliferative activities against both KB and HL-60 tumoral cell lines, showing IC50s in the low nanomolar range. It can be noticed also that this gold conjugated phosphorus dendrimer displayed low activity on the quiescent cell line EPC versus its potent antiproliferative activity against actively dividing cells. In order to evaluate the potential synergistic effect between Au(III) and Cu(II) and the influence of the number of Au(III) moieties on the surface of dendrimer against the proliferative activities, nine other original dendrimers with several surface modifications have been prepared. Whatever the number of Au(III) moieties introduced on the surface of dendrimers, all the dendrimers prepared displayed similar potency (nanomolar range) to 1G3-[Au48][AuCl4]48 against KB and HL60. In marked contrast synergistic effects on the antimicrobial activity of some of these phosphorus dendrimers are observed when both Au(III) and Cu(II) are present on the dendritic structure.


Assuntos
Cobre/química , Dendrímeros/química , Ouro/química , Fósforo/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Linhagem Celular Tumoral , Células HL-60 , Humanos , Estrutura Molecular
7.
Colloids Surf B Biointerfaces ; 155: 11-16, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28388470

RESUMO

Thrombin is an essential part of the blood coagulation system; it is a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, and catalyzes many other coagulation-related reactions. Absorption at its surface of small nanoparticles can completely change the biological properties of thrombin. We have analyzed the influence on thrombin of 3 different kinds of small nanoparticles: dendrimers (phosphorus-based, carbosilane based and polyamidoamine) and 2 hybrid systems containing carbosilane, viologen and phosphorus dendritic scaffolds in one single molecule, bearing different flexibility, size and surface charge. There was significant alteration in the rigidity of the rigid dendrimers in contrast to flexible dendrimers. These differences in their action are important in understanding interactions taking place at a bio-nanointerface.


Assuntos
Dendrímeros/química , Nanopartículas/química , Fósforo/química , Silanos/química , Trombina/química , Sítios de Ligação , Coagulação Sanguínea , Humanos , Cinética , Modelos Moleculares , Nanopartículas/ultraestrutura , Nanotecnologia , Ligação Proteica , Estrutura Secundária de Proteína , Soluções , Eletricidade Estática
8.
Colloids Surf B Biointerfaces ; 155: 159-165, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28419945

RESUMO

The etiology of Parkinson's disease (PD) relates to α-synuclein, a small protein with the ability to aggregate and form Lewy bodies. One of its prevention strategies is inhibition of α-synuclein oligomerization. We have investigated the interaction of α-synuclein and human serum albumin with 3,6-bis-О-di-О-galloyl-1,2,4-tri-О-galloyl-ß-d-glucose (a tannin isolated from the plant Rhus typhina). Using fluorescence spectroscopy method we found that this tannin interacts strongly with α-synuclein forming complexes. Circular dichroism analysis showed a time-dependent inhibition of α-synuclein aggregation in the presence of the tannin. On the other hand, 3,6-bis-О-di-О-galloyl-1,2,4-tri-О-galloyl-ß-d-glucose had a much stronger interaction with human serum albumin than α-synuclein. The calculated binding constant for tannin-protein interaction was considerably higher for albumin than α-synuclein. This tannin interacted with albumin through a "sphere of action" mechanism. The results lead to the conclusion that 3,6-bis-О-di-О-galloyl-1,2,4-tri-О-galloyl-ß-d-glucose is a potent preventive compound against Parkinson's disease. However, this tannin interacts very strongly with human serum albumin, significantly reducing the bioavailability of this compound.


Assuntos
Antiparkinsonianos/química , Rhus/química , Albumina Sérica/química , Taninos/química , alfa-Sinucleína/química , Antiparkinsonianos/isolamento & purificação , Humanos , Cinética , Extratos Vegetais/química , Agregados Proteicos , Ligação Proteica , Albumina Sérica/antagonistas & inibidores , Taninos/isolamento & purificação , alfa-Sinucleína/antagonistas & inibidores
9.
Int J Pharm ; 499(1-2): 247-254, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26724219

RESUMO

In the field of nanotechnology, dendrimers represent a new class of highly branched macromolecules that is receiving a stimulating and rising interest. The structural organization of these synthetic macromolecules provides promising opportunities for using them as nano-carriers of drugs or gene material to be delivered to the target cells. For applications of dendrimers as drug carriers, analysis of their specific interactions with biological structures at molecular level is very important. This paper describes the molecular interactions between cationic phosphorus dendrimers of third and fourth generation (CPD G3 and CPD G4) and 3 plasma regulatory proteins, namely aspartate transaminase, alkaline phosphatase and l-lactic dehydrogenase. Dendrimer-protein interactions were studied using spectrofluorimetric, circular dichroism and dynamic light scattering techniques. Their morphology in the presence or absence of dendrimers was examined by transmission electron microscopy. The results suggest that both dendrimers form positively charged complexes with HIV-derived peptides. The circular dichroism spectra show that these dendrimers can significantly change the secondary structure of proteins, indicating formation of protein/dendrimer complexes.


Assuntos
Dendrímeros/química , Portadores de Fármacos/química , Nanotecnologia/métodos , Fosfatase Alcalina/metabolismo , Aspartato Aminotransferases/metabolismo , Cátions/química , Dicroísmo Circular , Dendrímeros/metabolismo , Portadores de Fármacos/metabolismo , Difusão Dinâmica da Luz , L-Lactato Desidrogenase/metabolismo , Microscopia Eletrônica de Transmissão , Peptídeos/metabolismo , Fósforo/química , Espectrometria de Fluorescência
10.
J Membr Biol ; 249(1-2): 171-9, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26621636

RESUMO

We have examined the interaction between hydrolysable tannin 1-O-galloyl-4,6-hexahydroxydiphenoyl-ß-D-glucose (OGßDG) with neutral liposomes as a model of cell membranes composed of three lipids: lecithin, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at different mass ratios. OGßDG in the concentration range 0.5-15 µg/ml (0.4-12 µM) strongly interacts with liposomal membranes by changing their structure, surface charge and fluidity. Used OGßDG molecules decrease and increase the rigidity of hydrophilic surface and hydrophobic parts of liposomes, respectively. At higher concentrations of tannin (>15 µM), liposomes are aggregated. Fourier Transform Infra-Red (FTIR) analysis showed that mainly -OH groups from OGßDG and also PO(2-) groups from phospholipids are responsible for the interaction. Obtained data indicate the importance of membrane lipid composition in interactions between tannins and cells.


Assuntos
Lipossomos/química , Oenothera/química , Taninos/química , Taninos Hidrolisáveis/química , Bicamadas Lipídicas/química , Fluidez de Membrana , Estrutura Molecular , Tamanho da Partícula , Fosfolipídeos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Taninos/isolamento & purificação
11.
Int J Pharm ; 485(1-2): 288-94, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25796120

RESUMO

This paper examines a perspective to use newly engineered nanomaterials as effective and safe carriers for gene therapy of cancer. Three different groups of cationic dendrimers (PAMAM, phosphorus, and carbosilane) were complexed with anticancer siRNA and the biophysical properties of the dendriplexes created were analyzed. The potential of the dendrimers as nanocarriers for anticancer Bcl-xl, Bcl-2, Mcl-1 siRNAs and additionally a scrambled sequence siRNA has been explored. Dendrimer/siRNA complexes were characterised by various methods including fluorescence, zeta potential, dynamic light scattering, circular dichroism, gel electrophoresis and transmission electron microscopy. In this part of study, the transfection of complexes in HeLa and HL-60 cells was analyzed using both single apoptotic siRNAs and a mixture (cocktail) of them. Cocktails were more effective than single siRNAs, allowing one to decrease siRNAs concentration in treating cells. The dendrimers were compared as siRNA carriers, the most effective being the phosphorus-based ones. However, they were also the most cytotoxic on their own, so that in this regard the application of all dendrimers in anticancer therapy will be discussed.


Assuntos
Dendrímeros/química , Neoplasias/terapia , Fósforo/química , RNA Interferente Pequeno/genética , Terapêutica com RNAi/métodos , Silanos/química , Transfecção/métodos , Apoptose , Sobrevivência Celular , Dicroísmo Circular , Dendrímeros/toxicidade , Eletroforese em Gel de Ágar , Regulação Neoplásica da Expressão Gênica , Células HL-60 , Células HeLa , Heparina/química , Humanos , Luz , Microscopia Eletrônica de Transmissão , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Conformação de Ácido Nucleico , Tamanho da Partícula , Fósforo/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo , Espalhamento de Radiação , Silanos/toxicidade , Espectrometria de Fluorescência , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
12.
Int J Pharm ; 485(1-2): 261-9, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25791760

RESUMO

This paper examines a perspective on the use of newly engineered nanomaterials as effective and safe carriers of genes for the therapy of cancer. Three different groups of cationic dendrimers (PAMAM, phosphorus and carbosilane) were complexed with anticancer siRNA and their biophysical properties of the dendriplexes analyzed. The potential of the dendrimers as nanocarriers for anticancer siBcl-xl, siBcl-2, siMcl-1 siRNAs and a siScrambled sequence was explored. Dendrimer/siRNA complexes were characterized by methods including fluorescence, zeta potential, dynamic light scattering, circular dichroism, gel electrophoresis and transmission electron microscopy. Some of the experiments were done with heparin to check if siRNA can be easily disassociated from the complexes, and whether released siRNA maintains its structure after interaction with the dendrimer. The results indicate that siRNAs form complexes with all the dendrimers tested. Oligoribonucleotide duplexes can be released from dendriplexes after heparin treatment and the structure of siRNA is maintained in the case of PAMAM or carbosilane dendrimers. The dendrimers were also effective in protecting siRNA from RNase A activity. The selection of the best siRNA carrier will be made based on cell culture studies (Part B).


Assuntos
Dendrímeros/química , Fósforo/química , RNA Interferente Pequeno/química , Terapêutica com RNAi/métodos , Silanos/química , Transfecção , Dicroísmo Circular , Eletroforese em Gel de Ágar , Regulação Neoplásica da Expressão Gênica , Heparina/química , Humanos , Luz , Microscopia Eletrônica de Transmissão , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia , Conformação de Ácido Nucleico , Tamanho da Partícula , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espalhamento de Radiação , Espectrometria de Fluorescência , Transfecção/métodos , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
13.
Expert Opin Ther Pat ; 25(5): 539-48, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25645514

RESUMO

INTRODUCTION: The beginning of the nano-era started with the appearance of artificial nanosized supramolecular systems called nanomaterials and nanoparticles (NPs). AREAS COVERED: In the present review, we have analyzed the patents on phosphorus-based nanomaterials (fullerenes, quantum dots [QDs], graphene, liposomes, dendrimers, gold and silver NPs) in biology and medicine. Their impact in treatment of cancer, viral infections and cardiovascular diseases is discussed. EXPERT OPINION: Liposomes and dendrimers had the highest number of biomedical patents. The third candidates were QDs and the fourth and fifth were gold and silver NPs. Fullerenes and carbon nanotubes have the fewest applications in biology and medicine. Thus, our first conclusion was about the 'unifying nanotoxicology paradigm', that 'soft' NPs are significantly more biocompatible than 'hard' NPs. There has been a trend of these nanomaterials being applied in medicine drug and gene delivery, visualization of cells and pathologic processes, using them as antivirals and antimicrobials, contrast agents, antioxidants and photosensitizers. It was unexpected that no patents were found in which phosphorus NPs were used in 3D printing of bones and other biological tissues. The conclusion reached is that nanomaterials are promising tools in future medical applications.


Assuntos
Nanopartículas , Nanoestruturas , Fósforo/química , Animais , Doenças Cardiovasculares/terapia , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Humanos , Neoplasias/terapia , Patentes como Assunto , Impressão Tridimensional , Viroses/terapia
14.
Int J Pharm ; 473(1-2): 599-606, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25091374

RESUMO

The development of medical nanosystems requires knowledge of their behavior in vivo. Clinical chemistry tests are widely used to estimate the systemic toxicity of nanoparticles. In this paper we have explored the impact of small positively charged nanoparticles-poly(amidoamine), phosphorous and carbosilane dendrimers - on biochemical parameters of standardized serum in vitro. All the dendrimers could shift the main biochemical parameters. Thus, in the case of patients having the normal, but 'boundary', values of biochemical parameters, nanoparticle-induced changes can be wrongly interpreted as evidence of some dysfunctions (hepatic, renal, etc.). Moreover, the effects of nanoparticles of metals, carbon nanotubes, quantum dots, fullerenes, dendrimers having been sized up to 4000 nm and the hundreds of reactive groups, can be significantly higher. Thus, preliminary evaluation of any nanomaterial in vitro is required in clinical chemistry tests before its application in vivo to draw the correct conclusions and benefit animals.


Assuntos
Dendrímeros/química , Nanopartículas/química , Soro/química , Testes de Química Clínica , Fósforo/química , Silanos/química
15.
Int J Pharm ; 474(1-2): 42-9, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25108046

RESUMO

We have investigated whether polyamidoamine (PAMAM), phosphorus (pd) and viologen-phosphorus (vpd) dendrimers can prevent damage to embryonic mouse hippocampal cells (mHippoE-18) caused by rotenone, which is used as a pesticide, insecticide, and as a nonselective piscicide, that works by interfering with the electron transport chain in mitochondria. Several basic aspects, such as cell viability, production of reactive oxygen species and changes in mitochondrial transmembrane potential, were analyzed. mHippoE-18 cells were treated with these structurally different dendrimers at 0.1µM. A 1h incubation with dendrimers was followed by the addition of rotenone at 1µM, and a further 24h incubation. PAMAM, phosphorus and viologen-phosphorus dendrimers all increased cell viability (reduced cell death-data need to be compared with untreated controls). A lower level of reactive oxygen species and a favorable effect on mitochondrial system were found with PAMAM and viologen-phosphorus dendrimers. These results indicate reduced toxicity in the presence of dendrimers.


Assuntos
Dendrímeros/farmacologia , Fósforo/farmacologia , Poliaminas/farmacologia , Rotenona/antagonistas & inibidores , Rotenona/farmacologia , Viologênios/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dendrímeros/química , Relação Dose-Resposta a Droga , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Estrutura Molecular , Fósforo/química , Poliaminas/química , Espécies Reativas de Oxigênio/metabolismo , Rotenona/química , Relação Estrutura-Atividade
16.
Curr Med Chem ; 21(16): 1898-909, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24304285

RESUMO

AIMS: The objective was to study if cationic phosphorus dendrimers can be used as DC-based vaccine or adjuvant in anti-HIV-1 vaccine development when associated with HIV-1 derived peptides. MATERIALS & METHODS: The HIV derived peptides uptake in DC and the phenotype of iDC and mDC were studied using Flow Cytometry analysis. Migration of mDC was evaluated by an in vitro chemotaxis assay. Allogenic T-cells proliferative response induced by DC was studied using Flow Cytometry assays. Cytokines production was analysed by Diaclon DIAplex Th1/Th2/Inflammation kit. RESULTS: All phosphorus dendrimers showed the ability to deliver HIV-derived peptides in DC. The phosphorus dendrimers from second and third generations induced important changes in phenotype. Moreover, the treatment of mDC with the second generation dendrimer and derivated dendriplexes modified cellular migratory properties, altered their capacity to stimulate allogenic naïve T cells in vitro and impeded the production of pro-inflammatory cytokines. CONCLUSIONS: The phosphorus dendrimers cannot be used as vaccines because they would not have the ability to induce an immune response. The cationic phosphorus dendrimers associated with HIV-derived peptides have the ability to deliver peptides as non-viral vectors. However, there are other potential therapeutic applications of these compounds, for instance as topical antiinflammatory agents, as compounds for allograft rejection or autoimmune diseases and as agents inducing specific tolerance with antigen-loaded DC against allergy reaction. Nevertheless, these applications need to be evaluated.


Assuntos
Dendrímeros/uso terapêutico , Células Dendríticas/imunologia , Antígenos HIV/imunologia , Imunoterapia , Fósforo/química , Movimento Celular , Citocinas/metabolismo , Dendrímeros/química , Células Dendríticas/metabolismo , Humanos
17.
Molecules ; 18(10): 12222-40, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-24084024

RESUMO

A new class of viologen-phosphorus dendrimers (VPDs) has been recently shown to possess the ability to inhibit neurodegenerative processes in vitro. Nevertheless, in the Central Nervous Systems domain, there is little information on their impact on cell functions, especially on neuronal cells. In this work, we examined the influence of two VPD (VPD1 and VPD3) of zero generation (G0) on murine hippocampal cell line (named mHippoE-18). Extended analyses of cell responses to these nanomolecules comprised cytotoxicity test, reactive oxygen species (ROS) generation studies, mitochondrial membrane potential (ΔΨm) assay, cell death detection, cell morphology assessment, cell cycle studies, as well as measurements of catalase (CAT) activity and glutathione (GSH) level. The results indicate that VPD1 is more toxic than VPD3. However, these two tested dendrimers did not cause a strong cellular response, and induced a low level of apoptosis. Interestingly, VPD1 and VPD3 treatment led to a small decline in ROS level compared to untreated cells, which correlated with slightly increased catalase activity. This result indicates that the VPDs can indirectly lower the level of ROS in cells. Summarising, low-cytotoxicity on mHippoE-18 cells together with their ability to quench ROS, make the VPDs very promising nanodevices for future applications in the biomedical field as nanocarriers and/or drugs per se.


Assuntos
Dendrímeros/toxicidade , Viologênios/toxicidade , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Glutationa/metabolismo , Hipocampo/citologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Organofosfonatos/toxicidade , Espécies Reativas de Oxigênio/metabolismo
18.
Cell Mol Biol Lett ; 18(3): 459-78, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23893290

RESUMO

Dendrimers containing viologen (derivatives of 4,4'-bipyridyl) units in their structure have been demonstrated to exhibit antiviral activity against human immunodeficiency virus (HIV-1). It has also recently been revealed that novel dendrimers with both viologen units and phosphorus groups in their structure show different antimicrobial, cytotoxic and hemotoxic properties, and have the ability to influence the activity of cholinesterases and to inhibit α-synuclein fibrillation. Since the influence of viologen-phosphorus structures on basic cellular processes had not been investigated, we examined the impact of such macromolecules on the murine neuroblastoma cell line (N2a). We selected three water-soluble viologen-phosphorus (VPD) dendrimers, which differ in their core structure, number of viologen units and number and type of surface groups, and analyzed several aspects of the cellular response. These included cell viability, generation of reactive oxygen species (ROS), alterations in mitochondrial activity, morphological modifications, and the induction of apoptosis and necrosis. The MTT assay results suggest that all of the tested dendrimers are only slightly cytotoxic. Although some changes in ROS formation and mitochondrial function were detected, the three compounds did not induce apoptosis or necrosis. In light of these results, we can assume that the tested VPD are relatively safe for mouse neuroblastoma cells. Although more research on their safety is needed, VPD seem to be promising nanoparticles for further biomedical investigation.


Assuntos
Apoptose/efeitos dos fármacos , Dendrímeros/toxicidade , Fósforo/química , Viologênios/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dendrímeros/química , Relação Dose-Resposta a Droga , Citometria de Fluxo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Estrutura Molecular , Necrose/induzido quimicamente , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Espécies Reativas de Oxigênio/metabolismo
19.
Molecules ; 18(4): 4451-66, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23591925

RESUMO

There are many types of dendrimers used as nanomolecules for gene delivery but there is still an ongoing search for ones that are able to effectively deliver drugs to cells. The possibility of gene silencing using siRNA gives hope for effective treatment of numerous diseases. The aim of this work was to investigate in vitro biophysical properties of dendriplexes formed by siRNA and cationic phosphorus dendrimers of 3rd and 4th generation. First, using the ethidium bromide intercalation method, it was examined whether dendrimers have an ability to form complexes with siRNA. Next, the characterisation of dendriplexes formed at different molar ratios was carried out using biophysical methods. The effects of zeta potential, size and changes of siRNA conformation on the complexation with dendrimers were examined. It was found that both phosphorus dendrimers interacted with siRNA. The zeta potential values of dendriplexes ranged from negative to positive and the hydrodynamic diameter depended on the number of dendrimer molecules in the complex. Furthermore, using circular dichroism spectroscopy it was found that cationic phosphorus dendrimers changed only slightly the shape of siRNA CD spectra, thus they did not induce significant changes in the nucleic acid secondary structure during complex formation.


Assuntos
Dendrímeros/química , Fósforo/química , RNA Interferente Pequeno/farmacologia , Biofísica/métodos , Dicroísmo Circular , Etídio/química , Inativação Gênica , Técnicas de Transferência de Genes , Terapia Genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Nanopartículas/química , Tamanho da Partícula , Proteínas Proto-Oncogênicas c-bcr/genética , Proteínas Proto-Oncogênicas c-bcr/metabolismo , RNA Interferente Pequeno/química
20.
Mol Pharm ; 10(3): 1131-7, 2013 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-23379345

RESUMO

Inhibition of α-synuclein (ASN) fibril formation is a potential therapeutic strategy in Parkinson's disease and other synucleinopathies. The aim of this study was to examine the role of viologen-phosphorus dendrimers in the α-synuclein fibrillation process and to assess the structural changes in α-synuclein under the influence of dendrimers. ASN interactions with phosphonate and pegylated surface-reactive viologen-phosphorus dendrimers were examined by measuring the zeta potential, which allowed determining the number of dendrimer molecules that bind to the ASN molecule. The fibrillation kinetics and the structural changes were examined using ThT fluorescence and CD spectroscopy. Depending on the concentration of the used dendrimer and the nature of the reactive groups located on the surface, ASN fibrillation kinetics can be significantly reduced, and even, in the specific case of phosphonate dendrimers, the fibrillation can be totally inhibited at low concentrations. The presented results indicate that viologen-phosphorus dendrimers are able to inhibit ASN fibril formation and may be used as fibrillar regulating agents in neurodegenerative disorders.


Assuntos
Dendrímeros/química , Fósforo/química , Viologênios/química , alfa-Sinucleína/química , Dicroísmo Circular , Humanos
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