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1.
Int J Mol Sci ; 23(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36499695

RESUMO

Photodynamic therapy is one of the most patient friendly and promising anticancer therapies. The active ingredient is irradiated protoporphyrin IX, which is produced in the body that transfers energy to the oxygen-triggering phototoxic reaction. This effect could be enhanced by using iron chelators, which inhibit the final step of heme biosynthesis, thereby increasing the protoporphyrin IX concentration. In the presented work, we studied thiosemicarbazone derivative, which is a universal enhancer of the phototoxic effect. We examined several genes that are involved in the transport of the heme substrates and heme itself. The results indicate that despite an elevated level of ABCG2, which is responsible for the PpIX efflux, its concentration in a cell is sufficient to trigger a photodynamic reaction. This effect was not observed for 5-ALA alone. The analyzed cell lines differed in the scale of the effect and a correlation with the PpIX accumulation was observed. Additionally, an increased activation of the iron transporter MFNR1 was also detected, which indicated that the regulation of iron transport is essential in PDT.


Assuntos
Fotoquimioterapia , Tiossemicarbazonas , Humanos , Tiossemicarbazonas/farmacologia , Fotoquimioterapia/métodos , Protoporfirinas/farmacologia , Protoporfirinas/metabolismo , Ácido Aminolevulínico/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Heme/metabolismo , Ferro , Linhagem Celular Tumoral
2.
RSC Adv ; 12(11): 6377-6388, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35424628

RESUMO

The 5-aminolevulinic acid (5-ALA) prodrug is widely used in clinical applications, primarily for skin cancer treatments and to visualize brain tumors in neurosurgery. Unfortunately, its applications are limited by unfavorable pharmacological properties, especially low lipophilicity; therefore, efficient nanovehicles are needed. For this purpose, we synthesized and characterized two novel water-soluble fullerene nanomaterials containing 5-ALA and d-glucuronic acid components. Their physicochemical properties were investigated using NMR, XPS, ESI mass spectrometry, as well as TEM and SEM techniques. In addition, HPLC and fluorescence measurements were performed to evaluate the biological activity of the fullerene nanomaterials in 5-ALA delivery and photodynamic therapy (PDT); additional detection of selected mRNA targets was carried out using the qRT-PCR methodology. The cellular response to the [60]fullerene conjugates resulted in increased levels of ABCG2 and PEPT-1 genes, as determined by qRT-PCR analysis. Therefore, we designed a combination PDT approach based on two fullerene materials, C60-ALA and C60-ALA-GA, along with the ABCG2 inhibitor Ko143.

3.
Int J Mol Sci ; 22(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419163

RESUMO

Recent years have seen the dynamic development of methods for functionalizing the surface of implants using biomaterials that can mimic the physical and mechanical nature of native tissue, prevent the formation of bacterial biofilm, promote osteoconduction, and have the ability to sustain cell proliferation. One of the concepts for achieving this goal, which is presented in this work, is to functionalize the surface of NiTi shape memory alloy by an atypical glass-like nanocomposite that consists of SiO2-TiO2 with silver nanoparticles. However, determining the potential medical uses of bio(nano)coating prepared in this way requires an analysis of its surface roughness, tribology, or wettability, especially in the context of the commonly used reference coat-forming hydroxyapatite (HAp). According to our results, the surface roughness ranged between (112 ± 3) nm (Ag-SiO2)-(141 ± 5) nm (HAp), the water contact angle was in the range (74.8 ± 1.6)° (Ag-SiO2)-(70.6 ± 1.2)° (HAp), while the surface free energy was in the range of 45.4 mJ/m2 (Ag-SiO2)-46.8 mJ/m2 (HAp). The adhesive force and friction coefficient were determined to be 1.04 (Ag-SiO2)-1.14 (HAp) and 0.247 ± 0.012 (Ag-SiO2) and 0.397 ± 0.034 (HAp), respectively. The chemical data showed that the release of the metal, mainly Ni from the covered NiTi substrate or Ag from Ag-SiO2 coating had a negligible effect. It was revealed that the NiTi alloy that was coated with Ag-SiO2 did not favor the formation of E. coli or S. aureus biofilm compared to the HAp-coated alloy. Moreover, both approaches to surface functionalization indicated good viability of the normal human dermal fibroblast and osteoblast cells and confirmed the high osteoconductive features of the biomaterial. The similarities of both types of coat-forming materials indicate an excellent potential of the silver-silica composite as a new material for the functionalization of the surface of a biomaterial and the development of a new type of functionalized implants.


Assuntos
Níquel/química , Próteses e Implantes , Ligas de Memória da Forma/química , Dióxido de Silício/química , Prata/química , Titânio/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/química , Durapatita/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Humanos , Teste de Materiais/métodos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Propriedades de Superfície , Molhabilidade
4.
Eur J Med Chem ; 212: 113032, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33261897

RESUMO

Terpyridine derivatives are known from their broad application including anticancer properties. In this work we present the newly synthesized 4'-phenyl-2,2':6',2″-terpyridine group with high antiproliferative activity. We suggest that these compounds influence cellular redox homeostasis. Cancer cells are particularly susceptible to any changes in the redox balance because of their handicapped and inefficient antioxidant cellular systems. The antiproliferative activity of the studied compounds was tested on five different cell lines that represent several types of tumours; glioblastoma, leukemia, breast, pancreatic and colon. Additionally, we also tested their selectivity towards normal cells. We performed molecular biology studies in order to detect the response of a cell to its treatment with the compounds that were tested. We looked at the in-depth changes in the proteins and cellular pathways that lead to cell cycle inhibition (G0/G1 and S), and consequently, death on the apoptosis and autophagy pathways. We proved that the studied compounds targeted DNA as well. Special attention was paid to the targets connected with ROS generation.


Assuntos
Antineoplásicos/farmacologia , Piridinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Clivagem do DNA , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
J Photochem Photobiol B ; 199: 111585, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31450131

RESUMO

Thiosemicarbazone derivatives are known for their broad biological activity including their antitumor potency. The aim of the current study was to examine the effect of a novel series of non-toxic iron chelators on the accumulation of protoporphyrin IX after external 5-aminolevulonic acid administration. From this series we selected one the most promising derivative which causes a pronounced increase in the concentration of protoporphyrin IX. The increase of the photosensitizer concentration is necessary for the trigger the efficient therapeutic effect of the photodynamic reaction. For selected compound 2 we performed an examination of a panel of the genes that are involved in the heme biosynthesis and degradation. Results indicated the crucial roles of ferrochelatase and heme oxygenase in the described processes. Surprisingly, there was a strict dependence on the type of the tested cell line. A decrease in the expression of the two aforementioned enzymes after incubation with compound 2 and 5-aminolevulonic acid is a commonly known fact and we detected this trend for the MCF-7 and HCT 116 cell lines. However, we noticed the upregulation of the tested targets for the Hs683 cells. These unconventional results prompted us to do a more in-depth analysis of the described processes. In conclusion, we found that compound 2 is a novel, highly effective booster of photodynamic therapy that has prospective applications.


Assuntos
Antineoplásicos/síntese química , Ferro/química , Fármacos Fotossensibilizantes/síntese química , Protoporfirinas/química , Tiossemicarbazonas/metabolismo , Células A549 , Ácido Aminolevulínico/química , Ácido Aminolevulínico/metabolismo , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Ferroquelatase/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Heme Oxigenase (Desciclizante)/metabolismo , Humanos , Células MCF-7 , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia , Tiossemicarbazonas/síntese química
6.
Sci Rep ; 9(1): 6387, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31011161

RESUMO

A series of 116 small-molecule 1-hydroxynaphthalene-2-carboxanilides was designed based on the fragment-based approach and was synthesized according to the microwave-assisted protocol. The biological activity of all of the compounds was tested on human colon carcinoma cell lines including a deleted TP53 tumor suppressor gene. The mechanism of activity was studied according to the p53 status in the cell. Several compounds revealed a good to excellent activity that was similar to or better than the standard anticancer drugs. Some of these appeared to be more active against the p53 null cells than their wild-type counterparts. Intercalating the properties of these compounds could be responsible for their mechanism of action.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Desenho de Fármacos , Naftóis/síntese química , Naftóis/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Doxorrubicina/farmacologia , Células HCT116 , Humanos , Substâncias Intercalantes/farmacologia , Modelos Moleculares , Naftóis/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia
7.
ACS Appl Bio Mater ; 2(3): 987-998, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35021389

RESUMO

In recent years, one of the more important and costly problems of modern medicine is the need to replace or supplement organs in order to improve the quality of human life. In this field, promising solutions seem to have been implants which are based on NiTi alloys with shape memory effects. Unfortunately, this material is susceptible to the corrosion and release of toxic nickel to the human organism. Hence, its application as a long-term material is strongly limited. Therefore, this paper presents a new solution which should help to improve the functionality of the NiTi alloy and elongate its medical stability to use. The idea was focused on functionalization of the implant surface by a biocompatible, multifunctional coating without any impact on the features of the substrate, i.e., the martensitic transformation responsible for shape memory effects. For this purpose, we prepared a colloidal suspension, composed of ß-TCP (particle size ∼450 nm) and the Ag/SiO2 nanocomposite which due to the electrophoretic deposition (EPD) led to the formation of structurally atypical calcium phosphosilicate coating. Those biomaterials formed a crack-free coating, adhering well to the NiTi surface when distributed over the entire surface, with low concentration of metallic and oxide silver (<3 at. %). At the same time, the coat-forming materials had resulted in the growth of a Gram-negative bacterial biofilm. Additionally, the additive of the silver-silica composite enhances cell proliferation, effectively a few times higher than commonly used coat-forming materials (e.g., pure ß-TCP).

8.
Protoplasma ; 254(2): 657-668, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27154759

RESUMO

In apomictic Taraxacum species, the development of both the embryo and the endosperm does not require double fertilisation. However, a structural reduction of ovular transmitting tissue was not observed in apomictic dandelions. The aim of this study was to analyse the chemical composition of the cell walls to describe the presence of arabinogalactan proteins (AGPs), hemicellulose and some pectic epitopes in the micropylar transmitting tissue of apomictic Taraxacum. The results point to (1) the similar distribution of AGPs in different developmental stages, (2) the absence of highly methyl-esterified homogalacturonan (HG) in transmitting tissue of ovule containing a mature embryo sac and the appearance of this pectin domain in the young seed containing the embryo and endosperm, (3) the similar pattern of low methyl-esterified pectin occurrence in both an ovule and a young seed with an embryo and endosperm in apomictic Taraxacum and (4) the presence of hemicelluloses recognised by LM25 and LM21 antibodies in the reproductive structure of Taraxacum.


Assuntos
Apomixia , Epitopos/metabolismo , Mucoproteínas/metabolismo , Óvulo Vegetal/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismo , Taraxacum/metabolismo , Taraxacum/fisiologia , Endosperma/citologia , Imuno-Histoquímica , Óvulo Vegetal/citologia , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/ultraestrutura , Proteínas de Plantas/metabolismo , Taraxacum/embriologia , Taraxacum/ultraestrutura
9.
PLoS One ; 11(11): e0167426, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27893856

RESUMO

Brachypodium distachyon L. Beauv. (Brachypodium) is a species that has become an excellent model system for gaining a better understanding of various areas of grass biology and improving plant breeding. Although there are some studies of an in vitro Brachypodium culture including somatic embryogenesis, detailed knowledge of the composition of the main cell wall components in the embryogenic callus in this species is missing. Therefore, using the immunocytochemical approach, we targeted 17 different antigens of which five were against the arabinogalactan proteins (AGP), three were against extensins, six recognised pectic epitopes and two recognised hemicelluloses. These studies were complemented by histological and scanning electron microscopy (SEM) analyses. We revealed that the characteristic cell wall components of Brachypodium embryogenic calli are AGP epitopes that are recognised by the JIM16 and LM2 antibodies, an extensin epitope that is recognised by the JIM11 antibody and a pectic epitopes that is recognised by the LM6 antibody. Furthermore, we demonstrated that AGPs and pectins are the components of the extracellular matrix network in Brachypodium embryogenic culture. Additionally, SEM analysis demonstrated the presence of an extracellular matrix on the surface of the calli cells. In conclusion, the chemical compositions of the cell walls and ECMSN of Brachypodium callus show spatial differences that correlate with the embryogenic character of the cells. Thus, the distribution of pectins, AGPs and hemicelluloses can be used as molecular markers of embryogenic cells. The presented data extends the knowledge about the chemical composition of the embryogenic callus cells of Brachypodium.


Assuntos
Brachypodium/metabolismo , Calosidades/metabolismo , Parede Celular/metabolismo , Mucoproteínas/metabolismo , Técnicas de Embriogênese Somática de Plantas , Brachypodium/embriologia , Brachypodium/ultraestrutura , Parede Celular/ultraestrutura , Microscopia Eletrônica de Varredura , Pectinas/metabolismo , Proteínas de Plantas/metabolismo
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