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1.
J Environ Manage ; 297: 113312, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333311

RESUMO

An attempt has been made for the treatment of cyanide contaminated wastewater using a S-TiO2@rGO heterogeneous photocatalyst system immobilized on polyurethane foam (PUF) supporting materials. Further, to make the photocatalytic system more efficient and active under visible light, a highly efficient iron porphyrin derivative sensitizer viz. Fe-TCPP was synthesized and employed for cyanide degradation. To investigate the synthesized heterogeneous nano-composite S-TiO2@rGO-FeTCPP photocatalytic system, advanced techniques such as XRD, XPS, FT-IR, PL spectra, UV-vis DRS, FESEM, and EDS were utilized. The photocatalytic performance of the nanocomposite was evaluated in a suspended system and results revealed that about 75% of cyanide degradation was obtained at 100 mg/L of initial cyanide within 2 h. Whereas, at the same condition, more than 91% of cyanide degradation as well as 88% toxicity removal occurred by the PUF immobilized S-TiO2@rGO-FeTCPP solid-state photocatalytic system. First-order kinetics was applied to investigate the degradation of cyanide by the photocatalytic nanocomposite. From the kinetic study, the estimated first-order rate constant (Kf) in a solid-state photocatalytic system of the nanocomposite was 1.7 times superior to that of the suspended system. Further, the rate of photocatalytic activity was nearly 10.8 times greater than that of pure TiO2. This study demonstrated that the immobilized S-TiO2@rGO-FeTCPP photocatalytic system could be an efficient technique for degrading cyanide from industrial effluent.


Assuntos
Cianetos , Nanocompostos , Catálise , Grafite , Metaloporfirinas , Óxidos , Poliuretanos , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio
2.
Inorg Chem ; 60(17): 12870-12882, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34370470

RESUMO

Diheme cytochromes, the simplest members in the multiheme family, play substantial biochemical roles in enzymatic catalysis as well as in electron transfer. A series of diiron(III) porphyrin dimers have been synthesized as active site analogues of diheme cytochromes. The complexes contain six-coordinated iron(III) having thiophenol and imidazole at the fifth and sixth coordination sites, respectively. The iron centers in the complexes have been found to be in a low-spin state, as confirmed through solid-state Mössbauer and electron paramagnetic resonance (EPR) spectroscopic investigations. Mössbauer quadrupole splitting of complexes having mixed ligands is substantially larger than that observed when both axial ligands are the same. Rhombic types of EPR spectra with narrow separation between gx, gy, and gz clearly distinguish heme thiolate coordination compared to bis(imidazole)-ligated low-spin heme centers. The redox potential in diheme cytochromes has been found to be tuned by interheme interactions along with the nature of axial ligands. The effect of mixed-axial ligation within the diiron(III) porphyrin dimers is demonstrated by a positive shift in the Fe(III)/Fe(II) redox couple upon thiophenolate coordination compared to their bis(imidazole) analogues. The pKa of the imidazole also decides the extent of the shift for the Fe(III)/Fe(II) couple, while the potential of the mixed-ligated diiron(III) porphyrin dimer is more positive compared to their monomeric analogue. A variation of around 1.1 V for the Fe(III)/Fe(II) redox potential in the diiron(III) porphyrin dimer can be achieved with the combined effect of axial ligation and a metal spin state, while such a large variation in the redox potential, compared to their monomeric analogues, is attributed to the heme-heme interactions observed in dihemes. Moreover, theoretical calculations also support the experimental shifts in the redox potential values.


Assuntos
Imidazóis/química , Metaloporfirinas/química , Fenóis/química , Compostos de Sulfidrila/química , Citocromos/química , Teoria da Densidade Funcional , Espectroscopia de Ressonância de Spin Eletrônica , Heme/química , Ferro/química , Ligantes , Metaloporfirinas/síntese química , Modelos Químicos , Oxirredução , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Mossbauer
3.
Colloids Surf B Biointerfaces ; 207: 112010, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34392081

RESUMO

Rapid and efficient pesticide detection methods are particularly important due to the growing problems of pesticide residues. Here, a new azo-based porous organic polymer, Azo(Fe)PPOP, was prepared from octa(amino-phenyl)silsesquioxane (OAPS) and iron(III) 5,10,15,20-tetrakis(4-nitrophenyl)porphyrin (FeTPP(NO2)4) via a simple coupling reaction without the participation of metal catalysts. The inorganic cage units of OAPS endowed Azo(Fe)PPOP a porous framework, high surface area, favorably thermal and chemical stability. In Azo(Fe)PPOP, iron(III) porphyrin units were individually isolated in a fixed location, which could effectively avoid dimerization or self-oxidation as happens as in the case of porphyrin monomers. Such a unique structure made Azo(Fe)PPOP exhibit an excellent peroxidase-like catalytic performance in the presence of H2O2 and 3,3',5,5'-tetramethylbenzidine (TMB). Because of these advantages, we established a selective, facile, and sensitive colorimetric platform for direct detection of malathion within a very short time (3 min) with a low detection limit (8.5 nM). In addition, the recognition mechanism between Azo(Fe)PPOP and malathion was verified using X-ray photoelectron spectroscopy spectra. The practicality of the constructed platform was further executed by the detection of the pesticide in soil and food samples.


Assuntos
Compostos de Anilina/química , Colorimetria , Malation/análise , Metaloporfirinas , Compostos de Organossilício/química , Peroxidase/química , Compostos Férricos , Peróxido de Hidrogênio , Polímeros , Porosidade
4.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445313

RESUMO

High levels of hyaluronic acid (HA) in tumors correlate with poor outcomes with several types of cancers due to HA-driven support of adhesion, migration and proliferation of cells. In this study we explored how to enhance the degradation of HA into low-molecular fragments, which cannot prevent the immune system to fight tumor proliferation and metastases. The physiological solution of HA was exposed to oxidative degradation by ascorbate and cupric ions in the presence of either one of three ortho isomeric Mn(III) substituted N-alkyl- and alkoxyalkylpyridylporphyrins or para isomeric Mn(III) N-methylpyridyl analog, commonly known as mimics of superoxide dismutase. The changes in hyaluronan degradation kinetics by four Mn(III) porphyrins were monitored by measuring the alteration in the dynamic viscosity of the HA solution. The ortho compounds MnTE-2-PyP5+ (BMX-010, AEOL10113), MnTnBuOE-2-PyP5+ (BMX-001) and MnTnHex-2-PyP5+ are able to redox cycle with ascorbate whereby producing H2O2 which is subsequently coupled with Cu(I) to produce the •OH radical essential for HA degradation. Conversely, with the para analog, MnTM-4-PyP5+, no catalysis of HA degradation was demonstrated, due to its inertness towards redox cycling with ascorbate. The impact of different Mn(III)-porphyrins on the HA decay was further clarified by electron paramagnetic resonance spectrometry. The ability to catalyze the degradation of HA in a biological milieu, in the presence of cupric ions and ascorbate under the conditions of high tumor oxidative stress provides further insight into the anticancer potential of redox-active ortho isomeric Mn(III) porphyrins.


Assuntos
Ácido Ascórbico/química , Ácido Hialurônico/química , Metaloporfirinas/química , Cobre/química , Magnésio/química , Oxirredução , Superóxido Dismutase/metabolismo
5.
Biomolecules ; 11(6)2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205698

RESUMO

In order to maintain redox homeostasis, non-small-cell lung cancer (NSCLC) increases the activation of many antioxidant systems, including the heme-oxygenase (HO) system. The overexpression of HO-1 has been often associated with chemoresistance and tumor aggressiveness. Our results clearly showed an overexpression of the HO-1 protein in A549 NSCLC cell lines compared to that in non-cancerous cells. Thus, we hypothesized that "off-label" use of tin mesoporphyrin, a well-known HO activity inhibitor clinically used for neonatal hyperbilirubinemia, has potential use as an anti-cancer agent. The pharmacological inhibition of HO activity caused a reduction in cell proliferation and migration of A549. SnMP treatment caused an increase in oxidative stress, as demonstrated by the upregulation of reactive oxygen species (ROS) and the depletion of glutathione (GSH) content. To support these data, Western blot analysis was performed to analyze glucose-6-phosphate dehydrogenase (G6PD), TP53-induced glycolysis and the apoptosis regulator (TIGAR), and the glutamate cysteine ligase catalytic (GCLC) subunit, as they represent the main regulators of the pentose phosphate pathway (PPP) and glutathione synthesis, respectively. NCI-H292, a subtype of the NSCLC cell line, did not respond to SnMP treatment, possibly due to low basal levels of HO-1, suggesting a cellular-dependent antitumorigenic effect. Altogether, our results suggest HO activity inhibition may represent a potential target for selective chemotherapy in lung cancer subtypes.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células/efeitos dos fármacos , Glutationa/metabolismo , Heme Oxigenase-1/metabolismo , Neoplasias Pulmonares , Metaloporfirinas/farmacologia , Células A549 , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteína Supressora de Tumor p53/metabolismo
6.
J Nanobiotechnology ; 19(1): 200, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225744

RESUMO

BACKGROUND: Recent studies have demonstrated that multidrug resistance (MDR) is a critical factor in the low efficacy of cancer chemotherapy. The main mechanism of MDR arises from the overexpression of P-glycoprotein (P-gp), which actively enhances drug efflux and limits the effectiveness of chemotherapeutic agents. RESULTS: In this study, we fabricated a "combo" nanoagent equipping with triple synergistic strategies for enhancing antitumor efficacy against MDR cells. Tumor homing-penetrating peptide endows the nanosystem with targeting and penetrating capabilities in the first stage of tumor internalization. The abundant amine groups of polyethylenimine (PEI)-modified nanoparticles then trigger a proton sponge effect to promote endo/lysosomal escape, which enhances the intracellular accumulation and retention of anticancer drugs. Furthermore, copper tetrakis(4-carboxyphenyl)porphyrin (CuTCPP) encapsulated in the nanosystem, effectively scavenges endogenous glutathione (GSH) to reduce the detoxification mediated by GSH and sensitize the cancer cells to drugs, while simultaneously serving as a photoacoustic imaging (PAI) contrast agent for image visualization. Moreover, we also verify that these versatile nanoparticles in combination with PD-1/PD-L1 blockade therapy can not only activate immunological responses but also inhibit P-gp expression to obliterate primary and metastatic tumors. CONCLUSION: This work shows a significant enhancement in therapeutic efficacy against MDR cells and syngeneic tumors by using multiple MDR reversing strategies compared to an equivalent dose of free paclitaxel.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Nanopartículas/uso terapêutico , Animais , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Cobre , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Tratamento Farmacológico , Feminino , Compostos Heterocíclicos , Humanos , Lisossomos , Células MCF-7 , Metaloporfirinas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanomedicina , Nanopartículas/química , Compostos Organofosforados , Paclitaxel/farmacologia
7.
Chemistry ; 27(48): 12371-12379, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34137472

RESUMO

We investigated the photoionization and fragmentation of isolated metal protoporphyrin IX cations (MPPIX+ with M=Fe, Co, Zn) by means of vacuum-ultraviolet (VUV) action spectroscopy in the energy range of 8.5-35 eV. Experiments were carried out in the gas phase by interfacing an electrospray ionization tandem mass spectrometer with a synchrotron beamline. The mass spectra and partial ion yields show that photoexcitation of the precursor ions predominantly leads to . CH2 COOH radical side-chain losses of the macrocycle with additional methyl radical (. CH3 ) side-chain losses. Ionization, in contrast, leads to the formation of the intact ionized precursor and various doubly charged fragments which are mostly due to side-chain cleavages. Although statistical fragmentation dominates, we found evidence for non-statistical processes such as new fragments involving for example single and double H2 O losses, indicating that different relaxation mechanisms are at play upon photoionization compared to photoexcitation. The measured ionization energies were 9.6±0.2 eV, 9.4±0.2 eV and 9.6±0.2 eV for FePPIX+ , CoPPIX+ and ZnPPIX+ , respectively.


Assuntos
Metaloporfirinas , Cátions , Espectrometria de Massas , Análise Espectral , Raios Ultravioleta
8.
Analyst ; 146(14): 4585-4594, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34159957

RESUMO

A covalent organic framework (COF) is a promising type of porous material with customizable surface characteristics. Confining multiple catalytic units within a mesoporous COF can generate abundant active sites and improve the catalytic performance. In this work, a COF with both metalloporphyrin and a metal nanoparticle complex denoted as hemin/TAPB-DMTP-COF/AuNPs (TAPB: 1,3,5-tris(4-amino-phenyl)benzene, DMTP: 2,5-dimethoxyterephaldehyde, AuNPs: Au nanoparticles) has been successfully fabricated through a hierarchical encapsulation method. The as-synthesized composite was then employed to construct an electrochemical sensing platform for the efficient detection of bisphenol A (BPA). Under the optimal conditions, the hemin/TAPB-DMTP-COF/AuNP sensor presented a linear range of 0.01-3 µmol L-1 and a low detection limit of 3.5 nmol L-1. The satisfactory signal amplification is based on a triple-signaling amplification strategy due to the abundant Fe3+ sites of Fe-porphyrin, high conductivity of AuNPs and a large specific surface area of the TAPB-DMTP-COF. The proposed method was used to measure the content of BPA in different water samples with a satisfactory recovery from 95.5 to 104.0%, suggesting the great potential of the sensor in practical applications.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Metaloporfirinas , Compostos Benzidrílicos , Catálise , Ouro , Fenóis
9.
Biochim Biophys Acta Gen Subj ; 1865(7): 129897, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33811942

RESUMO

BACKGROUND: Photodynamic inactivation (PDI) is emerging as a promising alternative for cutaneous leishmaniasis (CL). The chemotherapy currently used presents adverse effects and cases of drug resistance have been reported. ZnTnHex-2-PyP4+ is a porphyrin with a high potential as a photosensitizer (PS) for PDI, due to its photophysical properties, structural stability, and cationic/amphiphilic character that can enhance interaction with cells. This study aimed to investigate the photodynamic effects mediated by ZnTnHex-2-PyP4+ on Leishmania parasites. METHODS: ZnTnHex-2-PyP4+ stability was evaluated using accelerated solvolysis conditions. The photodynamic action on promastigotes was assessed by (i) viability assays, (ii) mitochondrial membrane potential evaluation, and (iii) morphological analysis. The PS-promastigote interaction was studied. PDI on amastigotes and the cytotoxicity on macrophages were also analyzed. RESULTS: ZnTnHex-2-PyP4+, under submicromolar concentration, led to immediate inactivation of more than 95% of promastigotes. PDI promoted intense mitochondrial depolarization, loss of the fusiform shape, and plasma membrane wrinkling in promastigotes. Fluorescence microscopy revealed a punctate PS labeling in the parasite cytoplasm. PDI also led to reductions of ca. 64% in the number of amastigotes/macrophage and 70% in the infection index after a single treatment session. No noteworthy toxicity was observed on mammalian cells. CONCLUSIONS: ZnTnHex-2-PyP4+ is stable against demetallation and more efficient as PS than the ethyl analogue ZnTE-2-PyP4+, indicating readiness for evaluation in in vivo studies as an alternative approach to CL. GENERAL SIGNIFICANCE: This report highlighted promising photodynamic effects mediated by ZnTnHex-2-PyP4+ on Leishmania parasites, opening up perspectives for applications in CL pre-clinical assays and PDI of other microorganisms.


Assuntos
Leishmania/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Metaloporfirinas/farmacologia , Fotoquimioterapia/métodos , Zinco/química , Animais , Feminino , Leishmania/crescimento & desenvolvimento , Metaloporfirinas/química , Camundongos , Camundongos Endogâmicos BALB C
10.
Bioorg Med Chem Lett ; 40: 127931, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33705911

RESUMO

Green photosynthetic bacteria with an efficient light-harvesting system contain special chlorophyll molecules, called bacteriochlorophylls c, d, e, in their main antennae. In the biosynthetic pathway, a BciC enzyme is proposed to catalyze the hydrolysis of the C132-methoxycarbonyl group of chlorophyllide a, but the resulting C132-carboxy group has not been detected yet because it is spontaneously removed due to the instability of the ß-keto-carboxylic acid. In this study, the in vitro BciC enzymatic reactions of zinc methyl (131R/S)-hydroxy-mesochlorophyllides a were examined and a carboxylic acid possessing the C132S-OH was first observed as the hydrolyzed product of the C132-COOCH3.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Clorofilídeos/metabolismo , Metaloporfirinas/metabolismo , Proteínas de Bactérias/metabolismo , Chlorobi/enzimologia , Clorofilídeos/química , Hidrólise , Metaloporfirinas/química , Estrutura Molecular , Zinco/química
11.
J Neuroimmunol ; 354: 577544, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33756414

RESUMO

The antioxidant MnTBAP was previously shown to down-regulate the surface expression of CD4 molecule in T cells. This observation obviously holds great potential impact in a number of pathological human conditions, including autoimmunity. Three different single doses of MnTBAP reduced the frequency of CD4high cells. However, the median florescent intensity (MFI) was not different. Initiation of in vivo pharmacotherapy or vehicle control was performed inC57BL/6 mice that were actively immunized for experimental autoimmune encephalomyelitis (EAE). In contrast to published reports, the mean frequency of CD4high cells, and the median fluorescent intensity (MFI) of CD4 was similar in both treatment groups. 25-day survival following active immunization among the MnTBAP treated animals compared to vehicle controls was16.6 ± 6.9 days vs 23.6 ± 2.7 days; (P value <0.05). We conclude that MnTBAP (Sack and Herzog, 2009 (Sack and Herzog, 2009)) does not effectively downregulate CD4 expression in T cells in vivo, probably due to extensive mechanism that distinguishes it from an in vitro model (Harding, 1993 (Harding, 1993)) possesses toxic properties that may limit its clinic use in possible doses that could deliver the immunomodulation through down regulation of CD4 expression, and (Saizawa et al., 1987 (Saizawa et al., 1987)) has limited availability in specific tissues, including the CNS.


Assuntos
Antioxidantes/farmacologia , Antígenos CD4/biossíntese , Linfócitos T CD4-Positivos/efeitos dos fármacos , Encefalomielite Autoimune Experimental/imunologia , Metaloporfirinas/farmacologia , Animais , Antígenos CD4/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Regulação para Baixo , Camundongos , Camundongos Endogâmicos C57BL
12.
Chem Asian J ; 16(8): 1007-1015, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33617127

RESUMO

A series of bis-acryl functionalized porphyrins and their corresponding metalloporphyrins (M=Co, Mn) were synthesized and investigated for their antimicrobial properties through MIC screening and bacteria time-kill kinetic studies. The Mn(III) 4-(bis)methylphenyl-substituted-porphyrins showed superior batericidal activities even in the dark with low hemotoxicity and good cytotoxicity profile.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Metaloporfirinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Hemólise/efeitos dos fármacos , Humanos , Cinética , Metaloporfirinas/síntese química , Metaloporfirinas/química , Estrutura Molecular
13.
Angew Chem Int Ed Engl ; 60(15): 8220-8226, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33606332

RESUMO

Temperature can be used as clinical marker for tissue metabolism and the detection of inflammations or tumors. The use of magnetic resonance imaging (MRI) for monitoring physiological parameters like the temperature noninvasively is steadily increasing. In this study, we present a proof-of-principle study of MRI contrast agents (CA) for absolute and concentration independent temperature imaging. These CAs are based on azoimidazole substituted NiII porphyrins, which can undergo Light-Driven Coordination-Induced Spin State Switching (LD-CISSS) in solution. Monitoring the fast first order kinetic of back isomerisation (cis to trans) with standard clinical MR imaging sequences allows the determination of half-lives, that can be directly translated into absolute temperatures. Different temperature responsive CAs were successfully tested as prototypes in methanol-based gels and created temperature maps of gradient phantoms with high spatial resolution (0.13×0.13×1.1 mm) and low temperature errors (<0.22 °C). The method is sufficiently fast to record the temperature flow from a heat source as a film.


Assuntos
Compostos Azo/química , Meios de Contraste/química , Imidazóis/química , Imageamento por Ressonância Magnética , Metaloporfirinas/química , Temperatura , Conformação Molecular , Processos Fotoquímicos
14.
Inorg Chem ; 60(5): 3207-3217, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33587634

RESUMO

There have been two known categories of porphyrins: a meso-substituted porphyrin like meso-tetramesitylporphyrin (TMP) and a pyrrole-ß-substituted porphyrin like native porphyrins and 2,7,12,17-tetramethyl-3,8,13,18-tetramesitylporphyrin (TMTMP). To reveal the chemical and biological function of native hemes, we compare the reactivity of the oxoiron(IV) porphyrin π-cation radical complex (Compound I) of TMP (TMP-I) with that of TMTMP (TMTMP-I) for epoxidation, hydrogen abstraction, hydroxylation, sulfoxidation, and demethylation reactions. Kinetic analysis of these reactions indicated that TMP-I is much more reactive than TMTMP-I when the substrate is not sterically bulky. However, as the substrate is sterically bulkier, the difference of the reactivity between TMP-I and TMTMP-I becomes smaller, and the reactivity of TMP-I is comparable to that of TMTMP-I for a sterically hindered substrate. Since the redox potential of TMP-I is almost the same as that of TMTMP-I, we conclude that TMP-I is intrinsically more reactive than TMTMP-I for these atom transfer reactions, but the steric effect of TMP-I is stronger than that of TMTMP-I. This is contrary to the previous result for the single electron transfer reaction: TMTMP-I is faster than TMP-I. DFT calculations indicate that the orbital energies of the Fe═O moiety for TMTMP-I are higher than those for TMP-I. The difference in steric effect between TMP-I and TMTMP-I is explained by the distance from the mesityl group to the oxo ligand of Compound I. Significance of the pyrrole-ß-substituted structure of the hemes in native enzymes is also discussed on the basis of this study.


Assuntos
Radicais Livres/química , Metaloporfirinas/química , Desmetilação , Teoria da Densidade Funcional , Hidroxilação , Ferro/química , Cinética , Modelos Químicos , Oxirredução , Porfirinas/química
15.
Photodiagnosis Photodyn Ther ; 34: 102224, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33609757

RESUMO

Photodynamic therapy (PDT) is one of the treatments for cancer. This therapy uses a combination of a photosensitizer (PS), light irradiation, and oxygen O2, which is converted to cytotoxic 1O2 and other forms of reactive oxygen species (ROS), causing selective damage to the target tissue. In this work, we studied effect of two porphyrin photosensitizers TMPyP and ZnTPPS4 at three different concentrations (0.25, 0.5, 5µM) after two irradiation doses (5 and 25 J/cm2). Photodynamic efect of TMPyP and ZnTPPS4 were confirmed by a battery of in vitro tests including MTT, reactive oxygen species (ROS) production and mitochondrial membrane potential test (MMP). Morphological changes of the cells before and after treatment were imaged by atomic force microscopy (AFM). The most effective combination of irradiation dose and concentration for both PSs showed a concentration of 5 µM and a irradiation dose of 25 J/cm2 in both cell cultures.


Assuntos
Metaloporfirinas , Neoplasias , Fotoquimioterapia , Porfirinas , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/farmacologia , Espécies Reativas de Oxigênio
16.
Bioorg Med Chem ; 35: 116090, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33639594

RESUMO

Manganese(III) porphyrins (MnIIIPs) as MRI contrast agents (CAs) have drawn particular attention due to their high longitudinal relaxivity (r1) and unique biodistribution. In this work, two MnIIIP-based oligomers, MnPD and MnPT, were designed to further improve the relaxivity with ease of synthesis. The two compounds were fully characterized and their nuclear magnetic relaxation dispersion (NMRD) profiles were acquired with a fast field cycling NMR relaxometer. Both of the compounds exhibited extended high molar r1 at high fields, higher than that of Gd-DTPA, the first clinical gadolinium(III)-based MRI CA. The r1 value of per manganese atom increased with the increasing number of MnIIIP building blocks, suggesting rotational correlation time (τR) played dominant role in the r1 dispersion. The toxicity of the two MnIIIPs and the imaging effectiveness were estimated in vitro and in vivo. With good biocompatibility, significant contrast enhancement, and complete excretion in 24 h, MnPD and MnPT are both promising for high field clinical applications. The applied strategy also potentially provided a facile approach for creation of more MnIIIP oligomer as efficient T1 MRI CAs.


Assuntos
Meios de Contraste/química , Imageamento por Ressonância Magnética , Metaloporfirinas/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/farmacologia , Relação Dose-Resposta a Droga , Humanos , Masculino , Metaloporfirinas/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular
17.
Metallomics ; 13(3)2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33576808

RESUMO

Understanding the toxicological properties of MnIII-porphyrins (MnTPPS, MnTMPyP, or MnTBAP) can provide important biochemical rationales in developing them as the therapeutic drugs against protein tyrosine nitration-induced inflammation diseases. Here, we present a comprehensive understanding of the pH-dependent redox behaviors of these MnIII-porphyrins and their structural effects on catalyzing bovine serum albumin (BSA) nitration in the presence of H2O2 and NO2-. It was found that both MnTPPS and MnTBAP stand out in catalyzing BSA nitration at physiologically close condition (pH 8), yet they are less effective at pH 6 and 10. MnTMPyP was shown to have no ability to catalyze BSA nitration under all tested pHs (pH 6, 8, and 10). The kinetics and active intermediate determination through electrochemistry method revealed that both the pH-dependent redox behavior of the central metal cation and the antioxidant capability of porphin derivative contribute to the catalytic activities of three MnIII-porphyrins in BSA nitration in the presence of H2O2/NO2-. These comprehensive studies on the oxidative reactivity of MnIII-porphyrins toward BSA nitration may provide new clues for searching the manganese-based therapeutic drugs against the inflammation-related diseases.


Assuntos
Peróxido de Hidrogênio/química , Metaloporfirinas/química , Nitratos/química , Nitritos/química , Estresse Oxidativo , Soroalbumina Bovina/química , Tirosina/química , Animais , Bovinos , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Metaloporfirinas/metabolismo , Nitritos/metabolismo
18.
Molecules ; 26(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572895

RESUMO

The pivotal role played by potassium ions in the noncovalent synthesis of discrete porphyrin-calixarene nanostructures has been examined. The flattened-cone conformation adopted by the two cavities of octa-cationic calix[4]tube C4T was found to prevent the formation of complexes with well-defined stoichiometry between this novel water-soluble calixarene and the tetra-anionic phenylsulfonate porphyrin CuTPPS. Conversely, preorganization of C4T into a C4v-symmetrical scaffold, triggered by potassium ion encapsulation (C4T@K+), allowed us to carry out an efficient hierarchical self-assembly process leading to 2D and 3D nanostructures. The stepwise formation of discrete CuTPPS/C4T@K+ noncovalent assemblies, containing up to 33 molecular elements, was conveniently monitored by UV/vis spectroscopy by following the absorbance of the porphyrin Soret band.


Assuntos
Calixarenos/química , Ferroquelatase/química , Nanoestruturas/química , Porfirinas/química , Complexos de Coordenação/química , Íons/química , Metaloporfirinas/química , Conformação Molecular , Estrutura Molecular , Potássio/química , Ésteres do Ácido Sulfúrico/química
19.
Molecules ; 26(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546465

RESUMO

A novel double-decker porphyrin complex, bis{meso-tetrakis(4-N-alkylpyridiniumyl)porphyrinato}cerium, was prepared. Electrochemical measurements revealed that this complex exhibited reversible redox waves corresponding to a 1e- redox reaction of the cerium center. Treating the complex alternately with an oxidant and a reductant resulted in the reversible redox switching between the oxidized and reduced states in an organic solvent.


Assuntos
Cério/química , Metaloporfirinas/química , Metaloporfirinas/síntese química , Modelos Moleculares , Oxirredução
20.
Molecules ; 26(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562133

RESUMO

Bymeans of spectrophotometric titration and NMR spectroscopy, the selective binding ability ofthe Co(III)-5,15-bis-(3-hydroxyphenyl)-10,20-bis-(4-sulfophenyl)porphyrin (Со(III)Р1) andCo(III)-5,15-bis-(2-hydroxyphenyl)-10,20-bis-(4-sulfophenyl)porphyrin (Со(III)Р2) towards imidazole derivatives of various nature (imidazole (L1), metronidazole (L2), and histamine (L3)) in phosphate buffer (pH 7.4) has been studied. It was found that in the case of L2, L3 the binding of the "first" ligand molecule by porphyrinatesCo(III)P1 and Co(III)P2 occurs with the formation of complexes with two binding sites (donor-acceptor bond at the center and hydrogen bond at the periphery of the macrocycle), while the "second" ligand molecule is added to the metalloporphyrin only due to the formation of the donor-acceptor bond at the macrocycle coordination center. The formation of stable complexes with two binding sites has been confirmed by density functional theory method (DFT) quantum chemical calculations and two-dimensional NMR experiments. It was shown that among the studied porphyrinates, Co(III)P2 is more selective towards to L1-L3 ligands, and localization of cobalt porphyrinates in cetylpyridinium chloride (CPC) micelles does not prevent the studied imidazole derivatives reversible binding. The obtained materials can be used to develop effective receptors for recognition, delivery, and prolonged release of drug compounds to the sites of their functioning. Considering that cetylpyridinium chloride is a widely used cationic biocide as a disinfectant, the designed materials may also prove to be effective antimicrobial agents.


Assuntos
Cetilpiridínio/química , Cobalto/química , Imidazóis/química , Metaloporfirinas/química , Fosfatos/química , Tampões (Química) , Concentração de Íons de Hidrogênio , Modelos Moleculares , Conformação Molecular , Soluções
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