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1.
Int J Mol Sci ; 23(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35563666

RESUMO

For a while, gold nanoparticles (AuNPs) have been recognized as potential radiosensitizers in cancer radiation therapy, mainly due to their physical properties, making them appealing for medical applications. Nevertheless, the performance of AuNPs as radiosensitizers still raises important questions that need further investigation. Searching for selective prostate (PCa) radiosensitizing agents, we studied the radiosensitization capability of the target-specific AuNP-BBN in cancer versus non-cancerous prostate cells, including the evaluation of dose rate effects in comparison with non-targeted counterparts (AuNP-TDOTA). PCa cells were found to exhibit increased AuNP uptake when compared to non-tumoral ones, leading to a significant loss of cellular proliferation ability and complex DNA damage, evidenced by the occurrence of multiple micronucleus per binucleated cell, in the case of PC3 cells irradiated with 2 Gy of γ-rays, after incubation with AuNP-BBN. Remarkably, the treatment of the PC3 cells with AuNP-BBN led to a much stronger influence of the dose rate on the cellular survival upon γ-photon irradiation, as well as on their genomic instability. Overall, AuNP-BBN emerged in this study as a very promising nanotool for the efficient and selective radiosensitization of human prostate cancer PC3 cells, therefore deserving further preclinical evaluation in adequate animal models for prostate cancer radiotherapy.


Assuntos
Nanopartículas Metálicas , Neoplasias da Próstata , Radiossensibilizantes , Animais , Linhagem Celular Tumoral , Ouro/farmacologia , Humanos , Masculino , Próstata , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Radiossensibilizantes/farmacologia , Radiossensibilizantes/uso terapêutico
2.
J Environ Sci (China) ; 115: 215-226, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34969449

RESUMO

Particulate matter emissions (PM10) from the combustion, in a residential stove, of two commercial brands of certified (ENplus A1) pellets, a non-certified brand and laboratory made pellets of acacia were tested for their ability to induce ecotoxic, cytotoxic, and mutagenic responses in unicellular organisms and a human cell line. Ecotoxicity was evaluated through the Vibrio fischeri bioluminescence inhibition assay. Moreover, cytotoxicity was assessed at two time points (24- and 48-hr) through two complementary techniques in order to evaluate the cellular metabolic activity and membrane integrity of human lung epithelial cells A549. The Ames test using two Salmonella typhimurium strains (TA100 and TA98) was employed to assess the mutagenic potential of the polycyclic aromatic hydrocarbon fraction extracted from the PM10 samples. Results obtained with the bioluminescent bacteria indicated that only particles from the combustion of acacia pellets were toxic. All samples induced impairment on the A549 cells metabolic activity, while no significant release of lactate dehydrogenase was recorded. PM10 emissions from acacia pellets were the most cytotoxic, while samples from both certified pellets evoked significant cytotoxicity at lower doses. Cytotoxicity time-dependency was only observed for PM10 from the combustion of acacia pellets and one of the brands of certified pellets. Mutagenic activity was not detected in both S. typhimurium strains. This study emphasises the role of the raw material for pellet manufacturing on the toxicological profile of PM emissions. Alternative raw materials should be deeply investigated before their use in pelletisation and combustion in residential appliances.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Humanos , Testes de Mutagenicidade , Mutagênicos , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Emissões de Veículos , Madeira/química
3.
Medicina (Kaunas) ; 57(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406736

RESUMO

Background and objectives: Polyvascular atherosclerosis is frequent and associated with a high cardiovascular risk, although the mechanisms regulating the atherosclerosis extent to single or multiple arterial territories are still poorly understood. Inflammation regulates atherogenesis and soluble CD40 ligand (sCD40L) is an inflammatory mediator associated with the presence of single-territorial atherosclerosis. We assessed whether the sCD40L expression is associated with the atherosclerosis extent to single or multiple arterial territories and with the atherosclerosis severity in different territories. Materials and Methods: We prospectively enrolled 94 participants with no atherosclerosis (controls, n = 26); isolated coronary atherosclerosis (group 1, n = 20); coronary and lower extremity (LE) atherosclerosis (group 2, n = 18); coronary and carotid atherosclerosis (group 3, n = 12); and coronary, LE, and carotid atherosclerosis (group 4, n = 18). Serum sCD40L levels were quantified. Results: The sCD40L levels (ng/mL, mean (standard deviation)) were 4.0 (1.5), 5.6 (2.6), 7.2 (4.2), 5.9 (3.7), and 5.1 (2.4) in controls and groups 1 to 4, respectively (ANOVA p = 0.012). In nonrevascularized patients, the sCD40L levels were significantly higher in group 2 than in group 1 and were correlated with the number of LE diseased segments. Prior LE bypass surgery was associated with lower sCD40L levels. Coexistence of coronary and LE atherosclerosis was independently associated with the sCD40L levels. Conclusions: The sCD40L levels were increased in stable atherosclerosis, particularly in polyvascular coronary and LE atherosclerosis. The number of LE diseased segments and prior LE revascularization were associated with sCD40L expression. To our knowledge, these are novel data, which provide insights into the mechanisms underlying multi-territorial atherosclerosis expression. sCD40L may be a promising noninvasive tool for refining the stratification of the systemic atherosclerotic burden.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Ligante de CD40 , Humanos , Inflamação
4.
Inorg Chem ; 59(13): 9116-9134, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32578983

RESUMO

The interpretation of in vitro cytotoxicity data of Cu(II)-1,10-phenanthroline (phen) complexes normally does not take into account the speciation that complexes undergo in cell incubation media and its implications in cellular uptake and mechanisms of action. We synthesize and test the activity of several distinct Cu(II)-phen compounds; up to 24 h of incubation, the cytotoxic activity differs for the Cu complexes and the corresponding free ligands, but for longer incubation times (e.g., 72 h), all compounds display similar activity. Combining the use of several spectroscopic, spectrometric, and electrochemical techniques, the speciation of Cu-phen compounds in cell incubation media is evaluated, indicating that the originally added complex almost totally decomposed and that Cu(II) and phen are mainly bound to bovine serum albumin. Several methods are used to disclose relationships between structure, activity, speciation in incubation media, cellular uptake, distribution of Cu in cells, and cytotoxicity. Contrary to what is reported in most studies, we conclude that interaction with cell components and cell death involves the separate action of Cu ions and phen molecules, not [Cu(phen)n] species. This conclusion should similarly apply to many other Cu-ligand systems reported to date.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Fenantrolinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Bovinos , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Cobre/química , Cobre/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Fenantrolinas/síntese química , Fenantrolinas/metabolismo , Ligação Proteica , Soroalbumina Bovina/metabolismo
5.
Ecotoxicology ; 27(4): 430-439, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29572590

RESUMO

The mode of action for nanoparticle (NP) toxicity in aquatic organisms is not yet fully understood. In this work, a strategy other than toxicity testing was applied to Daphnia magna exposed to TiO2-NPs: the use of nuclear microscopy and the assessment of protein profile. D. magna is a keystone species broadly used as a model system in ecotoxicology. Titanium (Ti) was found in the D. magna digestive tract, mainly in the gut. The penetration of Ti into the epithelial region was greater at higher exposure levels and also observed in eggs in the brood pouch. The protein profile of individuals exposed to different concentrations showed that 2.8 and 5.6 mg/L TiO2-NP concentrations induced an over-expression of the majority of proteins, in particular proteins with molecular weight of ∼120, 85 and 15 kDa, while 11.2 mg/L TiO2-NP had an inhibitory effect on protein expression. The Matrix-assisted laser desorption ionization with tandem time of flight mass spectrometry (MALDI-TOF/TOF MS) analysis of these proteins consistently identified them as vitellogenin (Vtg)-like proteins, associated with enzymes involved in redox balance. These results indicate that Vtg-like proteins are up-regulated in D. magna exposed to TiO2-NPs. Vitellogenesis is associated with the reproduction system, suggesting that TiO2-NP exposure can impair reproduction by affecting this process. The precise mode of action of TiO2-NPs is still unclear and the results from this study are a first attempt to identify specific proteins as potential markers of TiO2-NP toxicity in D. magna, providing useful information for future research.


Assuntos
Daphnia/efeitos dos fármacos , Ecotoxicologia/métodos , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Proteínas de Artrópodes/metabolismo , Biomarcadores/metabolismo , Feminino , Espectrometria de Massas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
J Physiol ; 594(10): 2751-72, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26915902

RESUMO

KEY POINTS: The presynaptic protein α-synuclein forms aggregates during Parkinson's disease. Accumulating evidence suggests that the small soluble oligomers of α-synuclein are more toxic than the larger aggregates appearing later in the disease. The link between oligomer toxicity and structure still remains unclear. In the present study, we have produced two structurally-defined oligomers that have a similar morphology but differ in secondary structure. These oligomers were introduced into neocortical pyramidal cells during whole-cell recording and, using a combination of experimentation and modelling, electrophysiological parameters were extracted. Both oligomeric species had similar effects on neuronal properties reducing input resistance, time constant and increasing capacitance. The net effect was a marked reduction in neuronal excitability that could impact on network activity. ABSTRACT: The presynaptic protein α-synuclein (αSyn) aggregates during Parkinson's disease (PD) to form large proteinaceous amyloid plaques, the spread of which throughout the brain clinically defines the severity of the disease. During early stages of aggregation, αSyn forms soluble annular oligomers that show greater toxicity than much larger fibrils. These oligomers produce toxicity via a number of possible mechanisms, including the production of pore-forming complexes that permeabilize membranes. In the present study, two well-defined species of soluble αSyn oligomers were produced by different protocols: by polymerization of monomer and by sonication of fibrils. The two oligomeric species produced were morphologically similar, with both having an annular structure and consisting of approximately the same number of monomer subunits, although they differed in their secondary structure. Oligomeric and monomeric αSyn were injected directly into the soma of pyramidal neurons in mouse neocortical brain slices during whole-cell patch clamp recording. Using a combined experimental and modelling approach, neuronal parameters were extracted to measure, for the first time in the neocortex, specific changes in neuronal electrophysiology. Both species of oligomer had similar effects: (i) a significant reduction in input resistance and the membrane time constant and (ii) an increase in the current required to trigger an action potential with a resultant reduction in the firing rate. Differences in oligomer secondary structure appeared to produce only subtle differences in the activity of the oligomers. Monomeric αSyn had no effect on neuronal parameters, even at high concentrations. The oligomer-induced fall in neuronal excitability has the potential to impact both network activity and cognitive processing.


Assuntos
Potenciais de Ação/fisiologia , Líquido Intracelular/metabolismo , Células Piramidais/fisiologia , alfa-Sinucleína/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Humanos , Líquido Intracelular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Células Piramidais/efeitos dos fármacos , alfa-Sinucleína/farmacologia
7.
Am J Psychoanal ; 76(3): 281-294, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28638134

RESUMO

This paper discusses ideas about depression as a paradigmatic symptom of contemporaneous psychological suffering and makes a comparison between depression and melancholia. The ideas we describe were stimulated by two comparative studies that were conducted based on an analysis of how depressed subjects relate to the concept of desire, their feelings of shame and their self-image in today's age.


Assuntos
Depressão/psicologia , Transtorno Depressivo/psicologia , Narcisismo , Autoimagem , Vergonha , Mecanismos de Defesa , Humanos
8.
Arch Toxicol ; 89(11): 1909-30, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26140917

RESUMO

Metal oxide nanoparticles in sunscreens provide broad-spectrum ultraviolet protection to skin. All studies to assess dermal penetration of nanoparticles have unanimously concluded that the overwhelming majority of nanoparticles remain on the outer surface of the skin. However, possibly due to many different experimental protocols in use, conclusions over the potential penetration to viable skin are mixed. Here, we review several factors that may influence experimental results for dermal penetration including the species studied (human, or animal model), size and coating of the metal oxide nanoparticles, composition of the sunscreen formulation, site of sunscreen application, dose and number of applications, duration of the study, types of biological samples analysed, methods for analysing samples, exposure to UV and skin flexing. Based on this information, we suggest an appropriate research agenda involving international collaboration that maximises the potential for dermal absorption of nanoparticles, and their detection, under normal conditions of sunscreen use by humans. If results from this research agenda indicate no absorption is observed, then concerns over adverse health effects from the dermal absorption of nanoparticles in sunscreens may be allayed.


Assuntos
Nanopartículas Metálicas/administração & dosagem , Absorção Cutânea , Protetores Solares/administração & dosagem , Administração Cutânea , Animais , Humanos , Cooperação Internacional , Óxidos/química , Tamanho da Partícula , Projetos de Pesquisa , Pele/metabolismo , Protetores Solares/farmacocinética
9.
Int J Environ Health Res ; 25(1): 67-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24670229

RESUMO

Occupational exposure to lead (Pb) requires continuous surveillance to assure, as much as possible, safe and healthful working conditions. This study addresses the suitability of assessing Pb exposure in relevant workers using their exhaled breath condensate (EBC). This study enrolled workers of two different Pb processing industries characterized by moderate and high Pb exposure levels in the work environment, and a group of non-exposed individuals working in offices who served as baseline for Pb exposure. The EBC-Pb of workers reflected the Pb levels in the work environment of all three settings, although the relationship with B-Pb was not clear. The lack of correlation between EBC-Pb and B-Pb most probably indicates the time lag for Pb to enter in the two body pools. The EBC-Pb seems to reflect immediate exposure, providing a prompt signature of Pb in the environmental that may interact directly with the organ. By delivering short-term evaluation of exposure, EBC-Pb represents a clear advantage in biomonitoring and may become an interesting tool for estimating organ burden.


Assuntos
Poluentes Ocupacionais do Ar/metabolismo , Testes Respiratórios , Monitoramento Ambiental/métodos , Chumbo/metabolismo , Exposição Ocupacional , Adulto , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Biochim Biophys Acta ; 1828(8): 1899-908, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23590997

RESUMO

Menadione (MEN), a polycyclic aromatic ketone, was shown to promote cell injury by imposing massive oxidative stress and has been proposed as a promising chemotherapeutic agent for the treatment of cancer diseases. The mechanisms underlying MEN-induced mitochondrial dysfunction and cell death are not yet fully understood. In this work, a systematic study was performed to unveil the effects of MEN on membrane lipid organization, using models mimicking mitochondrial membranes and native mitochondrial membranes. MEN was found to readily incorporate in membrane systems composed of a single phospholipid (phosphatidylcholine) or the lipids dioleoylphosphatidylcholine, dioleoylphosphatidylethanolamine and tetraoleoylcardiolipin at 1:1:1 molar ratio, as well as in mitochondrial membranes. Increased permeability in both membrane models, monitored by calcein release, seemed to correlate with the extent of MEN incorporation into membranes. MEN perturbed the physical properties of vesicles composed of dipalmitoylphosphatidylcholine or dipalmitoylphosphatidylethanolamine plus tetraoleoylcardiolipin (at 7:3 molar ratio), as reflected by the downshift of the lipid phase transition temperature and the emergence of a new transition peak in the mixed lipid system, detected by DSC. (31)P NMR studies revealed that MEN favored the formation of non-lamellar structures. Also, quenching studies with the fluorescent probes DPH and TMA-DPH showed that MEN distributed across the bilayer thickness in both model and native mitochondrial membranes. MEN's ability to promote alterations of membrane lipid organization was related with its reported mitochondrial toxicity and promotion of apoptosis, predictably involved in its anti-carcinogenic activity.


Assuntos
Bicamadas Lipídicas/metabolismo , Lipídeos de Membrana/metabolismo , Membranas Artificiais , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Fosfatidiletanolaminas/metabolismo , Vitamina K 3/metabolismo , Biofísica , Varredura Diferencial de Calorimetria , Permeabilidade da Membrana Celular , Fluoresceínas/metabolismo , Fluorescência , Humanos , Bicamadas Lipídicas/química , Lipídeos de Membrana/química , Mitocôndrias/química , Membranas Mitocondriais/química , Fosfatidiletanolaminas/química , Espectrofotometria , Vitamina K 3/química
11.
Acta Derm Venereol ; 94(1): 14-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23728724

RESUMO

Measurement of the concentration of iron in the skin, if correlated with total body iron stores, may enable better informed decisions on when to initiate, change or stop therapy in hereditary heamochromatosis. Naïve haemochromatosis patients with iron overload and with C282Y and/or H63D HFE mutations were evaluated at the following time-points: disease diagnosis, end of the therapy programme, and 6 months after the end of therapy. The distribution and concentration of iron in the skin were assessed by quantitative nuclear microscopy methods, in parallel with serum and plasma iron concentration. Iron content in the liver was determined by nuclear magnetic resonance. Iron accumulated in the epidermis; its concentration increased from outer to inner layers, being maximal in the basal layer (7.33 ± 0.98 µmol/g). At all 3 time-points, most of the iron was associated with the extracellular space. During the phlebotomy programme the iron content of the skin and the liver decreased by a factor of 2. These data suggest that measurements of iron concentration in the epidermis, which is a readily accessible tissue, reflect iron overload in the liver.


Assuntos
Epiderme/química , Hemocromatose/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Ferro/análise , Fígado/química , Proteínas de Membrana/genética , Pele/metabolismo , Adulto , Espaço Extracelular/química , Feminino , Hemocromatose/genética , Hemocromatose/terapia , Proteína da Hemocromatose , Humanos , Ferro/sangue , Ferro/farmacocinética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação , Flebotomia
12.
J Surg Case Rep ; 2024(1): rjae004, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38283413

RESUMO

Cranial suture diastases are an uncommon clinical entity, with post craniotomy diastases being a previously undescribed finding in literature to our best knowledge. Herein, we report a case of a 28-year-old adult who underwent a second-stage low-grade glioma surgery 7 months after initial surgery. This study presents coronal suture diastases adjacent to the previously performed craniotomy. After literature and pathophysiology review, we found it to be unique and that the craniotomy can resemble the mechanical stress of trauma.

13.
Dalton Trans ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953883

RESUMO

Monoanionic gold bis(dithiolene) complexes were recently shown to display activity against ovarian cancer cells, Gram-positive bacteria, Candida strains and the rodent malaria parasite, P. berghei. To date, only monoanionic gold(III) bis(dithiolene) complexes with a thiazoline backbone substituted with small alkyl chains have been evaluated for biomedical applications. We now analyzed the influence of the length and the hydrophobicity vs. hydrophilicity of these complexes' alkyl chain on their anticancer and antiplasmodial properties. Isomer analogues of these monoanionic gold(III) bis(dithiolene) complexes, this time with a thiazole backbone, were also investigated in order to assess the influence of the nature of the heterocyclic ligand on their overall chemical and biological properties. In this report we present the total synthesis of four novel monoanionic gold(III) bis(dithiolene) complexes with a long alkyl chain and a polyoxygenated (PEG) chain aiming to improve their solubility and biological properties. Our results showed that the complexes with a PEG chain showed promising anticancer and antiplasmodial activities beside improved solubility, a key parameter in drug discovery and development.

14.
Pharmaceutics ; 15(2)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36839886

RESUMO

Gold(III) bisdithiolate complexes have been reported as potential antimicrobial and antitumoral agents. The complex [Au(cdc)2]- (cdc=cyanodithioimido carbonate) displayed antimicrobial and outstanding antitumor activity against the ovarian cancer cells A2780 and A2780cisR, which are sensitive and resistant to cisplatin, respectively. However, poor water solubility may hamper its clinical use. Block copolymer micelles (BCMs) may solubilize hydrophobic drugs, improving their bioavailability and circulation time in blood. Aiming to provide water solubility, prolonged availability, and enhanced therapeutic indexes, BCMs loaded with [Au(cdc)2]- were synthesized and characterized. The BCM-[Au(cdc)2] micelles were prepared with a loading efficiency of 64.6% and a loading content of 35.3 mg [Au(cdc)2]-/gBCM. A hydrodynamic diameter of 77.31 ± 27.00 nm and a low polydispersity index of 0.18 indicated that the micelles were homogenous and good candidates for drug delivery. Cytotoxic activity studies against A2780/A2780cisR cells showed that BCM-[Au(cdc)2] maintained relevant cytotoxic activity comparable to the cytotoxicity observed for the same concentration of gold complexes. The Au uptake in A2780 cells, determined by PIXE, was ca. 17% higher for BCMs-[Au(cdc)2] compared to [Au(cdc)2]-. The BCMs-[Au(cdc)2] presented antimicrobial activity against S. aureus Newman and C. glabrata CBS138. These results evidenced the potential of BCM-[Au(cdc)2] for drug delivery and its promising anticancer and antimicrobial activities.

15.
Nanotheranostics ; 7(1): 22-40, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36593794

RESUMO

Over the last decades, gold nanoparticles (AuNPs) have proven to be remarkable tools for drug delivery and theranostic applications in cancer treatment. On the other hand, Pt(IV) prodrugs have been employed as an interesting alternative to the more common Pt(II) complexes, such as cisplatin, for cancer chemotherapy. Searching to design an image-guided nanocarrier to deliver selectively Pt(IV) prodrugs to tumors expressing the gastrin releasing peptide receptor (GRPR), we have synthesized small core AuNPs carrying a thiolated DOTA derivative, a GRPR-targeting bombesin analog (BBN[7-14]) and a Pt(IV) prodrug attached to the AuNPs without (AuNP-BBN-Pt1) or with a PEGylated linker (AuNP-BBN-Pt2 and AuNP-BBN-Pt3). In the GRPR+ prostate cancer PC3 cell line, the cytotoxic activity of the designed AuNP-BBN-Pt nanoparticles is strongly influenced by the presence of the PEGylated linker. Thus, AuNP-BBN-Pt1 displayed the lowest IC50 value (9.3 ± 2.3 µM of Pt), which is comparable to that exhibited by cisplatin in the same cell line. In contrast, AuNP-BBN-Pt1 showed an IC50 value of 97 ± 18 µM of Pt in the non-tumoral RWPE-1 prostate cells with a much higher selective index (SI) towards PC3 cells (SI = 10) when compared with cisplatin (SI = 1.3). The AuNPs were also successfully labeled with 67Ga and the resulting 67Ga-AuNP-BBN-Pt were used to assess their cellular uptake in PC3 cells, with AuNP-BBN-Pt1 also displaying the highest cellular internalization. Finally, intratumoral administration of 67Ga-AuNP-BBN-Pt1 in a PC3 tumor-bearing mice showed a prolonged retention of the nanoparticle compared to that of cisplatin, with optimal in vivo stability and 20% of the injected platinum remaining in the tumor after 72 h post-injection. Furthermore, microSPECT imaging studies confirmed the uptake and considerable retention of the 67Ga-labeled AuNPs in the tumors. Overall, these results show the potential of these targeted AuNPs loaded with Pt(IV) prodrugs for prostate cancer theranostics.


Assuntos
Nanopartículas Metálicas , Pró-Fármacos , Neoplasias da Próstata , Humanos , Masculino , Animais , Camundongos , Pró-Fármacos/farmacologia , Ouro , Cisplatino/farmacologia , Nanopartículas Metálicas/química , Receptores da Bombesina/metabolismo , Neoplasias da Próstata/metabolismo , Polietilenoglicóis
16.
ChemMedChem ; 18(14): e202300074, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37098105

RESUMO

Four new Cu(I) complexes of the general formula [Cu(PP)(LL)][BF4 ], in which PP is a phosphane ligand (triphenylphosphane or 1,2-bis(diphenylphosphano)ethane (dppe)) and LL is a bioactive thiosemicarbazone ligand (4-(methyl)-1-(5-nitrofurfurylidene)thiosemicarbazone) or 4-(ethyl)-1-(5-nitrofurfurylidene)thiosemicarbazone) were synthesized and fully characterized by classical analytical and spectroscopic methods. The anti-trypanosome and anticancer activities were investigated in vitro on Trypanosoma cruzi and in two human cancer cell lines (ovarian OVCAR3 and prostate PC3). To test the selectivity toward parasites and cancer cells, the cytotoxicity on normal monkey kidney VERO and human dermal fibroblasts HDF cells was also evaluated. The new heteroleptic complexes were more cytotoxic on T. cruzi and chemoresistant prostate PC3 cells than the benchmark drugs nifurtimox and cisplatin. The compounds also showed a high level of cellular internalization by the OVCAR3 cells and, in particular, those containing the dppe phosphane showed activation of the cell death mechanism via apoptosis. On the other hand, the production of reactive oxygen species induced by these complexes was not evident.


Assuntos
Anti-Infecciosos , Antineoplásicos , Doença de Chagas , Complexos de Coordenação , Neoplasias Ovarianas , Tiossemicarbazonas , Feminino , Masculino , Humanos , Cobre/química , Linhagem Celular Tumoral , Antiparasitários/farmacologia , Apoptose , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/química , Ligantes , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
17.
J Am Chem Soc ; 134(3): 1454-7, 2012 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-22239162

RESUMO

Albumin transports both fatty acids and zinc in plasma. Competitive binding studied by isothermal titration calorimetry revealed that physiologically relevant levels of fatty acids modulate the Zn-binding capacity of albumin, with far-reaching implications for biological zinc speciation. The molecular mechanism for this effect is likely due to a large conformational change elicited by fatty acid binding to a high-affinity interdomain site that disrupts at least one Zn site. Albumin may be a molecular device to "translate" certain aspects of the organismal energy state into global zinc signals.


Assuntos
Ácidos Graxos/sangue , Ácidos Graxos/metabolismo , Albumina Sérica/metabolismo , Zinco/sangue , Zinco/metabolismo , Transporte Biológico , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Albumina Sérica/química
18.
Microsc Microanal ; 18(5): 1060-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23046744

RESUMO

The effects of plasma lipid overload on pancreatic islet function and on mineral imbalance are issues under debate. However, the outcomes may be biased by the different metabolisms of different species. This prospective study evaluated whether a high fat diet intake changed the distribution of physiologically relevant elements within pancreatic endocrine and exocrine tissues of Sprague Dawley rats and New Zealand White rabbits. Nuclear microscopy techniques provided images of the specimen density and structure as well as the elemental distributions and quantification of P, S, Cl, K, Ca, Fe, and Zn using unstained cryosections of pancreas. Our results indicate that pancreatic islets in normal rats and rabbits had lower tissue density and higher Ca, Fe, and Zn content compared to exocrine tissue, and that rabbit islets exhibit the highest Zn content (3,300 µg/g in rabbits versus 510 µg/g in rats). Fat diet intake resulted in large deposits of fat in the pancreas, which modified the density contrast of tissues and also resulted in a twofold decrease of Ca and Zn concentrations in islets of both rats and rabbits. This result indicates that a fat diet leads to a reduction in essential trace element concentrations in pancreas, which in turn may hamper endocrine function.


Assuntos
Gorduras na Dieta/metabolismo , Minerais/metabolismo , Pâncreas/metabolismo , Animais , Dieta Hiperlipídica , Ilhotas Pancreáticas/química , Ilhotas Pancreáticas/metabolismo , Masculino , Minerais/análise , Microscopia Nuclear , Pâncreas/química , Coelhos , Ratos , Ratos Sprague-Dawley
19.
Antibiotics (Basel) ; 11(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36009879

RESUMO

The cytotoxic activity of four sets of camphorimine complexes based on the Cu(I), Cu(II), Ag(I), and Au(I) metal sites were assessed against the cisplatin-sensitive A2780 and OVCAR3 ovarian cancer cells. The results showed that the gold complexes were ca. one order of magnitude more active than the silver complexes, which in turn were ca. one order of magnitude more active than the copper complexes. An important finding was that the cytotoxic activity of the Ag(I) and Au(I) camphorimine complexes was higher than that of cisplatin. Another relevant aspect was that the camphorimine complexes did not interact significantly with DNA, in contrast with cisplatin. The cytotoxic activity of the camphorimine complexes displayed a direct relationship with the cellular uptake by OVCAR3 cells, as ascertained by PIXE (particle-induced X-ray emission). The levels of ROS (reactive oxygen species) formation exhibited an inverse relationship with the reduction potentials for the complexes with the same metal, as assessed by cyclic voltammetry. In order to gain insight into the toxicity of the complexes, their cytotoxicity toward nontumoral cells (HDF and V79 fibroblasts) was evaluated. The in vivo cytotoxicity of complex 5 using the nematode Caenorhabditis elegans was also assessed. The silver camphorimine complexes displayed the highest selectivity coefficients (activity vs. toxicity).

20.
J Mater Chem B ; 10(47): 9794-9815, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36373493

RESUMO

Glioblastoma multiforme (GBM) is the most common and fatal primary brain tumor, and is highly resistant to conventional radiotherapy and chemotherapy. Therefore, the development of multidrug resistance and tumor recurrence are frequent. Given the poor survival with the current treatments, new therapeutic strategies are urgently needed. Radiotherapy (RT) is a common cancer treatment modality for GBM. However, there is still a need to improve RT efficiency, while reducing the severe side effects. Radiosensitizers can enhance the killing effect on tumor cells with less side effects on healthy tissues. Herein, we present our pioneering study on the highly stable and amphiphilic metallacarboranes, ferrabis(dicarbollides) ([o-FESAN]- and [8,8'-I2-o-FESAN]-), as potential radiosensitizers for GBM radiotherapy. We propose radiation methodologies that utilize secondary radiation emissions from iodine and iron, using ferrabis(dicarbollides) as iodine/iron donors, aiming to achieve a greater therapeutic effect than that of a conventional radiotherapy. As a proof-of-concept, we show that using 2D and 3D models of U87 cells, the cellular viability and survival were reduced using this treatment approach. We also tested for the first time the proton boron fusion reaction (PBFR) with ferrabis(dicarbollides), taking advantage of their high boron (11B) content. The results from the cellular damage response obtained suggest that proton boron fusion radiation therapy, when combined with boron-rich compounds, is a promising modality to fight against resistant tumors. Although these results are encouraging, more developments are needed to further explore ferrabis(dicarbollides) as radiosensitizers towards a positive impact on the therapeutic strategies for GBM.


Assuntos
Boro , Prótons
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