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1.
Annu Rev Biophys ; 51: 453-471, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35133854

RESUMO

Some oxidoreductase enzymes use redox-active tyrosine, tryptophan, cysteine, and/or glycine residues as one-electron, high-potential redox (radical) cofactors. Amino-acid radical cofactors typically perform one of four tasks-they work in concert with a metallocofactor to carry out a multielectron redox process, serve as storage sites for oxidizing equivalents, activate the substrate molecules, or move oxidizing equivalents over long distances. It is challenging to experimentally resolve the thermodynamic and kinetic redox properties of a single-amino-acid residue. The inherently reactive and highly oxidizing properties of amino-acid radicals increase the experimental barriers further still. This review describes a family of stable and well-structured model proteins that was made specifically to study tyrosine and tryptophan oxidation-reduction. The so-called α3X model protein system was combined with very-high-potential protein film voltammetry, transient absorption spectroscopy, and theoretical methods to gain a comprehensive description of the thermodynamic and kinetic properties of protein tyrosine and tryptophan radicals.


Assuntos
Aminoácidos , Triptofano , Aminoácidos/química , Radicais Livres/metabolismo , Cinética , Proteínas/química , Termodinâmica , Triptofano/química , Tirosina/química , Tirosina/metabolismo
2.
Contact Dermatitis ; 86(4): 241-253, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34982482

RESUMO

A major research topic consists of revealing the contribution of radical-mediated reactions in dermatological diseases related to xenobiotic-induced stress to succeed risk-assessment procedures protecting producers and consumers. Allergic contact dermatitis is the clinically relevant consequence of skin sensitization, one of the most critical occupational and environmental health issues related to xenobiotics exposure. The first key event identified for the skin sensitization process to a chemical is its aptitude to react with epidermal proteins and form antigenic structures that will further trigger the immune response. Many chemical sensitizers are suspected to react through mechanisms involving radical intermediates. This review focuses on the recent progress we have accomplished over the last few years studying radical intermediates derived from skin-sensitizing chemicals by electron paramagnetic resonance in combination with the spin-trapping technique. Our work is carried out "from the molecule", performing studies in solution, "to the tissue", by the development of a methodology on a reconstructed human epidermis model, very close in terms of histology and metabolic/enzymatic activity to real human epidermis, that can be used as suitable biological tissue model. The benefits are to test chemicals under conditions close to human use and real-life sensitization exposures and benefit from the three-dimensional (3D) microenvironment.


Assuntos
Alérgenos , Dermatite Alérgica de Contato , Alérgenos/efeitos adversos , Alérgenos/química , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radicais Livres/química , Radicais Livres/metabolismo , Humanos , Peróxido de Hidrogênio , Detecção de Spin/métodos
3.
Biochemistry ; 61(2): 107-116, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34989236

RESUMO

The radical S-adenosyl-l-methionine (SAM) enzyme HydG cleaves tyrosine to generate CO and CN- ligands of the [FeFe] hydrogenase H-cluster, accompanied by the formation of a 4-oxidobenzyl radical (4-OB•), which is the precursor to the HydG p-cresol byproduct. Native HydG only generates a small amount of 4-OB•, limiting detailed electron paramagnetic resonance (EPR) spectral characterization beyond our initial EPR lineshape study employing various tyrosine isotopologues. Here, we show that the concentration of trapped 4-OB• is significantly increased in reactions using HydG variants, in which the "dangler Fe" to which CO and CN- bind is missing or substituted by a redox-inert Zn2+ ion. This allows for the detailed characterization of 4-OB• using high-field EPR and electron nuclear double resonance spectroscopy to extract its g-values and 1H/13C hyperfine couplings. These results are compared to density functional theory-predicted values of several 4-OB• models with different sizes and protonation states, with a best fit to the deprotonated radical anion configuration of 4-OB•. Overall, our results depict a clearer electronic structure of the transient 4-OB• radical and provide new insights into the radical SAM chemistry of HydG.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas Ferro-Enxofre/metabolismo , S-Adenosilmetionina/metabolismo , Shewanella/metabolismo , Proteínas de Bactérias/química , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Radicais Livres/metabolismo , Proteínas Ferro-Enxofre/química , Modelos Moleculares , S-Adenosilmetionina/química , Shewanella/química
4.
Pharm Res ; 39(2): 399-410, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35083639

RESUMO

PURPOSES: The primary objectives of this study were to investigate the degradation mechanisms of freeze-dried monoclonal antibody (mAb) formulations under mechanical grinding, assess the sensitivity and suitability of various particle analysis techniques, analyze the structure of the collected subvisible particles (SbVPs), and analyze the antioxidant mechanism of methionine (Met) under degradation process to gain a thorough understanding of the phenomenon. METHODS: The freeze-dried mAb-X formulations underwent grinding, and the resultant SbVPs were characterized through visual inspection, flow imaging microscopy, dynamic light scattering, ultraviolet-visible spectroscopy, and size-exclusion high-performance liquid chromatography. We further evaluated the effect of different temperatures and the free radical scavenger Met on SbVP formation. The produced free radicals were detected using electron paramagnetic resonance, and Met S-oxide formation was detected using liquid chromatography-mass spectrometry. In addition, we analyzed the obtained SbVPs using capillary electrophoresis sodium dodecyl sulfate and Fourier transform infrared spectroscopy. RESULTS: Grinding leads to SbVP formation under high temperature and free radical formation. Free radicals produced during grinding require the participation of a macromolecule. Met could then bind to the produced free radicals, thus partially protecting mAb-X from degradation while itself undergoing oxidation to form Met(O). Sensitivity differences between different particle analysis techniques were evaluated, and the obtained SbVPs showed significant changes in secondary structure and the formation of covalent aggregates and fragments. CONCLUSIONS: Met plays the role of an antioxidant in protecting macromolecules by quenching the free radicals produced during grinding. To thoroughly characterize SbVPs, multiple and orthogonal particle analysis techniques should be used, and if necessary, SbVPs should be processed by enrichment to accurately analyze primary and high order structures.


Assuntos
Anticorpos Monoclonais/química , Sequestradores de Radicais Livres/química , Radicais Livres/metabolismo , Liofilização , Metionina/química , Composição de Medicamentos , Estabilidade de Medicamentos , Estabilidade Proteica , Fatores de Tempo
5.
Mol Pharm ; 19(1): 354-357, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34889598

RESUMO

Two alkylated verdazyl radicals (AlkVZs) were investigated as active compounds for photoinitiated controlled MCF-7 cell death. Observed results unambiguously showed that AlkVZ could be a potential structural moiety for the design of a novel family of photodynamic therapy agents. The main advantage of the proposed substances is an oxygen-independent generation of active radicals, which play a pivotal role in the treatment of oxygen-deficient tumors.


Assuntos
Morte Celular/efeitos dos fármacos , Células MCF-7/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Radicais Livres/metabolismo , Humanos
6.
Int J Mol Sci ; 22(23)2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34884668

RESUMO

Reductive radical stress represents the other side of the redox spectrum, less studied but equally important compared to oxidative stress. The reactivity of hydrogen atoms (H•) and hydrated electrons (e-aq) connected with peptides/proteins is summarized, focusing on the chemical transformations of methionine (Met) and cystine (CysS-SCys) residues into α-aminobutyric acid and alanine, respectively. Chemical and mechanistic aspects of desulfurization processes with formation of diffusible sulfur-centered radicals, such as methanethiyl (CH3S•) and sulfhydryl (HS•) radicals, are discussed. These findings are further applied to biomimetic radical chemistry, modeling the occurrence of tandem protein-lipid damages in proteo-liposomes and demonstrating that generation of sulfur-centered radicals from a variety of proteins is coupled with the cis-trans isomerization of unsaturated lipids in membranes. Recent applications to pharmaceutical and pharmacological contexts are described, evidencing novel perspectives in the stability of formulations and mode of action of drugs, respectively.


Assuntos
Aminoácidos Sulfúricos/metabolismo , Proteínas/metabolismo , Estresse Fisiológico , Animais , Radicais Livres/metabolismo , Raios gama , Humanos , Oxirredução
7.
Yakugaku Zasshi ; 141(12): 1359-1372, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34853208

RESUMO

In the present paper, generation, detection and protection of reactive oxygen species (ROS)/free radicals in relation to the author's research over about 20 years are reviewed. ROS/free radicals are generally generated physically, chemically and biologically, and they are harmful to living organisms by inducing various disorders and diseases. To prevent the harmful effects of ROS/free radicals, antioxidants are believed to be useful. Among many methods to detect ROS/free radicals, ESR technique is a direct method and is described in detail in this review. Several topics such as the production of ROS/free radicals by low temperature atmospheric pressure plasma, the evaluation of antioxidant activity using hemolysis of erythrocytes and the protective effects of antioxidants against X-ray induced damage to mice, are presented.


Assuntos
Antioxidantes , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radicais Livres/análise , Espécies Reativas de Oxigênio/análise , Animais , Antioxidantes/farmacologia , Membrana Eritrocítica/metabolismo , Radicais Livres/metabolismo , Hemólise , Humanos , Camundongos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/análise , Superóxidos/metabolismo
8.
Bull Exp Biol Med ; 172(2): 214-217, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34855094

RESUMO

Using the rat model of posttraumatic osteoarthrosis of the knee joint induced by surgical transection of their anterior cruciate ligaments, we showed that irreversible loss of hyaluronan by the extracellular matrix of the joint cartilage tissue against the background of oxidative stress accompanied by accumulation of intermediate LPO products in blood serum and formation of thiol system incompetence was one of the key patterns of dystrophic degeneration of the cartilage tissue. Considerable metabolic shifts were associated with structural modification of the articular hyaline cartilage: its thinning and a decrease of chondrocyte density and their abnormal spatial distribution in the matrix with predominance of solitary isolated cells with signs of karyopyknosis and karyolysis.


Assuntos
Cartilagem Articular/patologia , Traumatismos do Joelho/metabolismo , Peroxidação de Lipídeos/fisiologia , Osteoartrite do Joelho/metabolismo , Animais , Animais não Endogâmicos , Antioxidantes/metabolismo , Cartilagem Articular/metabolismo , Modelos Animais de Doenças , Radicais Livres/metabolismo , Traumatismos do Joelho/complicações , Traumatismos do Joelho/patologia , Articulação do Joelho/metabolismo , Articulação do Joelho/patologia , Masculino , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/patologia , Ratos
9.
Anticancer Res ; 41(12): 5881-5902, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34848443

RESUMO

Cancer remains the second leading cause of death worldwide. Research is currently focused on finding novel anticancer therapies and elucidating their mechanisms of action. Cellular redox balance is a promising target for new therapies, as cancer cells already have elevated levels of oxidizing agents due to hypermetabolism and genetic instability. Although free radicals are actively involved in vital cellular signaling pathways, they have also been implicated in certain diseases, including cancer. The aim of this review was to highlight the involvement of oxidative stress in the mechanism of action of anticancer agents. The difference in cellular redox balance between normal and cancer cells is discussed as a potential anticancer target, along with various examples of approved or experimental drugs that may alter the redox state. These drugs are presented in relation to their pro-oxidant or antioxidant mechanisms, with the consequent goal of underscoring the importance of such mechanisms in the overall efficacy of anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Neoplasias/etiologia , Neoplasias/metabolismo , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antioxidantes/química , Antioxidantes/uso terapêutico , Radicais Livres/antagonistas & inibidores , Radicais Livres/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Estresse Oxidativo/efeitos dos fármacos , Relação Estrutura-Atividade , Resultado do Tratamento
10.
Int J Mol Sci ; 22(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34948180

RESUMO

The excessive formation of reactive oxygen species (ROS) and impairment of defensive antioxidant systems leads to a condition known as oxidative stress. The main source of free radicals responsible for oxidative stress is mitochondrial respiration. The deleterious effects of ROS on cellular biomolecules, including DNA, is a well-known phenomenon that can disrupt mitochondrial function and contribute to cellular damage and death, and the subsequent development of various disease processes. In this review, we summarize the most important findings that implicated mitochondrial oxidative stress in a wide variety of pathologies from Alzheimer disease (AD) to autoimmune type 1 diabetes. This review also discusses attempts to affect oxidative stress as a therapeutic avenue.


Assuntos
Mitocôndrias/metabolismo , Doenças Mitocondriais/fisiopatologia , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/farmacologia , Doença/etiologia , Radicais Livres/metabolismo , Humanos , Espécies Reativas de Oxigênio/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo
11.
Biochemistry (Mosc) ; 86(10): 1256-1274, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34903155

RESUMO

The review presents current concepts of the molecular mechanisms of oxidative stress development and describes main stages of the free-radical reactions in oxidative stress. Endogenous and exogenous factors of the oxidative stress development, including dysfunction of cell oxidoreductase systems, as well as the effects of various external physicochemical factors, are discussed. The review also describes the main components of the antioxidant defense system and stages of its evolution, with a special focus on peroxiredoxins, glutathione peroxidases, and glutathione S-transferases, which share some phylogenetic, structural, and catalytic properties. The substrate specificity, as well as the similarities and differences in the catalytic mechanisms of these enzymes, are discussed in detail. The role of peroxiredoxins, glutathione peroxidases, and glutathione S-transferases in the regulation of hydroperoxide-mediated intracellular and intercellular signaling and interactions of these enzymes with receptors and non-receptor proteins are described. An important contribution of hydroperoxide-reducing enzymes to the antioxidant protection and regulation of such cell processes as growth, differentiation, and apoptosis is demonstrated.


Assuntos
Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/química , Radicais Livres/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/química , Glutationa Peroxidase/metabolismo , Glutationa Transferase/química , Glutationa Transferase/metabolismo , Humanos , Peroxirredoxinas/química , Peroxirredoxinas/metabolismo , Filogenia
12.
J Nanobiotechnology ; 19(1): 390, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34823543

RESUMO

BACKGROUND: Although lower temperature (< 45 °C) photothermal therapy (LPTT) have attracted enormous attention in cancer therapy, the therapeutic effect is still unsatisfying when applying LPTT alone. Therefore, combining with other therapies is urgently needed to improve the therapeutic effect of LPTT. Recently reported oxygen-irrelevant free radicals based thermodynamic therapy (TDT) exhibit promising potential for hypoxic tumor treatment. However, overexpression of glutathione (GSH) in cancer cells would potently scavenge the free radicals before their arrival to the specific site and dramatically diminish the therapeutic efficacy. METHODS AND RESULTS: In this work, a core-shell nanoplatform with an appropriate size composed of arginine-glycine-aspartate (RGD) functioned polydopamine (PDA) as a shell and a triphenylphosphonium (TPP) modified hollow mesoporous manganese dioxide (H-mMnO2) as a core was designed and fabricated for the first time. This nanostructure endows a size-controllable hollow cavity mMnO2 and thickness-tunable PDA layers, which effectively prevented the pre-matured release of encapsulated azo initiator 2,2'-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIBI) and revealed pH/NIR dual-responsive release performance. With the mitochondria-targeting ability of TPP, the smart nanocomposites (AIBI@H-mMnO2-TPP@PDA-RGD, AHTPR) could efficiently induce mitochondrial associated apoptosis in cancer cells at relatively low temperatures (< 45 °C) via selectively releasing oxygen-irrelevant free radicals in mitochondria and facilitating the depletion of intracellular GSH, exhibiting the advantages of mitochondria-targeted LPTT/TDT. More importantly, remarkable inhibition of tumor growth was observed in a subcutaneous xenograft model of osteosarcoma (OS) with negligible side effects. CONCLUSIONS: The synergistic therapy efficacy was confirmed by effectively inducing cancer cell death in vitro and completely eradicating the tumors in vivo. Additionally, the excellent biosafety and biocompatibility of the nanoplatforms were confirmed both in vitro and in vivo. Taken together, the current study provides a novel paradigm toward oxygen-independent free-radical-based cancer therapy, especially for the treatment of hypoxic solid tumors.


Assuntos
Radicais Livres , Nanopartículas Metálicas/química , Mitocôndrias , Terapia Fototérmica , Animais , Compostos Azo/química , Linhagem Celular Tumoral , Temperatura Baixa , Feminino , Radicais Livres/análise , Radicais Livres/metabolismo , Humanos , Imidazóis/química , Compostos de Manganês/química , Camundongos , Camundongos Nus , Mitocôndrias/química , Mitocôndrias/metabolismo , Óxidos/química
13.
Molecules ; 26(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34833934

RESUMO

The aim of this study was to evaluate the bioremoval of anthracycline antibiotics (daunomycin-DNR, doxorubicin-DOX, and mitoxantrone-MTX) by immobilized mycelium of B. adusta CCBAS 930. The activity of oxidoreductases: versatile peroxidases (VP), superoxide dismutase (SOD), catalase (CAT), and glucose oxidase (GOX), and the levels of phenolic compounds (PhC) and free radicals (SOR) were determined during the biotransformation of anthracyclines by B. adusta strain CCBAS 930. Moreover, the phytotoxicity (Lepidium sativum L.), biotoxicity (MARA assay), and genotoxicity of anthracyclines were evaluated after biological treatment. After 120 h, more than 90% of anthracyclines were removed by the immobilized mycelium of B. adusta CCBAS 930. The effective biotransformation of anthracyclines was correlated with detoxification and reduced genotoxicity.


Assuntos
Antraciclinas/metabolismo , Coriolaceae/metabolismo , Citostáticos/metabolismo , Micélio/metabolismo , Biotransformação/fisiologia , Radicais Livres/metabolismo , Lepidium sativum/metabolismo , Oxirredutases/metabolismo , Fenóis/metabolismo
14.
Cell Mol Life Sci ; 78(24): 8187-8208, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34738149

RESUMO

There is significant contemporary interest in the application of enzymes to replace or augment chemical reagents toward the development of more environmentally sound and sustainable processes. In particular, copper radical oxidases (CRO) from Auxiliary Activity Family 5 Subfamily 2 (AA5_2) are attractive, organic cofactor-free catalysts for the chemoselective oxidation of alcohols to the corresponding aldehydes. These enzymes were first defined by the archetypal galactose-6-oxidase (GalOx, EC 1.1.3.13) from the fungus Fusarium graminearum. The recent discovery of specific alcohol oxidases (EC 1.1.3.7) and aryl alcohol oxidases (EC 1.1.3.47) within AA5_2 has indicated a potentially broad substrate scope among fungal CROs. However, only relatively few AA5_2 members have been characterized to date. Guided by sequence similarity network and phylogenetic analysis, twelve AA5_2 homologs have been recombinantly produced and biochemically characterized in the present study. As defined by their predominant activities, these comprise four galactose 6-oxidases, two raffinose oxidases, four broad-specificity primary alcohol oxidases, and two non-carbohydrate alcohol oxidases. Of particular relevance to applications in biomass valorization, detailed product analysis revealed that two CROs produce the bioplastics monomer furan-2,5-dicarboxylic acid (FDCA) directly from 5-hydroxymethylfurfural (HMF). Furthermore, several CROs could desymmetrize glycerol (a by-product of the biodiesel industry) to D- or L-glyceraldehyde. This study furthers our understanding of CROs by doubling the number of characterized AA5_2 members, which may find future applications as biocatalysts in diverse processes.


Assuntos
Cobre/metabolismo , Radicais Livres/metabolismo , Proteínas Fúngicas/metabolismo , Fusarium/enzimologia , Metaloproteínas/metabolismo , Oxirredutases/metabolismo , Filogenia , Oxirredutases do Álcool/química , Oxirredutases do Álcool/metabolismo , Cobre/química , Radicais Livres/química , Proteínas Fúngicas/química , Metaloproteínas/química , Oxirredução , Oxirredutases/química , Conformação Proteica , Especificidade por Substrato
15.
Nucleic Acids Res ; 49(21): 12556-12576, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34755876

RESUMO

CstR is a persulfide-sensing member of the functionally diverse copper-sensitive operon repressor (CsoR) superfamily. While CstR regulates the bacterial response to hydrogen sulfide (H2S) and more oxidized reactive sulfur species (RSS) in Gram-positive pathogens, other dithiol-containing CsoR proteins respond to host derived Cu(I) toxicity, sometimes in the same bacterial cytoplasm, but without regulatory crosstalk in cells. It is not clear what prevents this crosstalk, nor the extent to which RSS sensors exhibit specificity over other oxidants. Here, we report a sequence similarity network (SSN) analysis of the entire CsoR superfamily, which together with the first crystallographic structure of a CstR and comprehensive mass spectrometry-based kinetic profiling experiments, reveal new insights into the molecular basis of RSS specificity in CstRs. We find that the more N-terminal cysteine is the attacking Cys in CstR and is far more nucleophilic than in a CsoR. Moreover, our CstR crystal structure is markedly asymmetric and chemical reactivity experiments reveal the functional impact of this asymmetry. Substitution of the Asn wedge between the resolving and the attacking thiol with Ala significantly decreases asymmetry in the crystal structure and markedly impacts the distribution of species, despite adopting the same global structure as the parent repressor. Companion NMR, SAXS and molecular dynamics simulations reveal that the structural and functional asymmetry can be traced to fast internal dynamics of the tetramer. Furthermore, this asymmetry is preserved in all CstRs and with all oxidants tested, giving rise to markedly distinct distributions of crosslinked products. Our exploration of the sequence, structural, and kinetic features that determine oxidant-specificity suggest that the product distribution upon RSS exposure is determined by internal flexibility.


Assuntos
Proteínas de Bactérias/química , Cobre/química , Simulação de Dinâmica Molecular , Óperon , Proteínas Repressoras/química , Sulfetos/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cobre/metabolismo , Cristalografia por Raios X , Cisteína/química , Cisteína/genética , Cisteína/metabolismo , Polarização de Fluorescência , Radicais Livres/química , Radicais Livres/metabolismo , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/metabolismo , Espectroscopia de Ressonância Magnética , Conformação Proteica , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Sulfetos/metabolismo , Enxofre/química , Enxofre/metabolismo , Tolueno/análogos & derivados , Tolueno/química
16.
Pharmacol Res ; 174: 105968, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34752922

RESUMO

Cellular redox status has been considered as a focal point for the pathogenesis of multiple disorders. High and persistent levels of free radicals kick off inflammation and associated disorders. Though oxidative stress at high levels is harmful but at low levels it has been shown to exert cytoprotective effects. Therefore, cytoprotection by perturbation in cellular redox balance is a leading strategy for therapeutic interventions. Prooxidants are potent redox modifiers that generate mild oxidative stress leading to a spectrum of bioactivities. Naphthoquinones are a group of highly reactive organic chemical species that interact with biological systems owing to their prooxidants nature. Owing to the ability of naphthoquinones and its derivatives to perturb redox balance in a cell and modulate redox signaling, they have been in epicenter of drug development for plausible utilization in multiple clinical settings. The present review highlights the potential of 1,4-naphthoquinone and its natural derivatives (plumbagin, juglone, lawsone, menadione, lapachol and ß-lapachone) as redox modifiers with anti-inflammatory, anti-cancer, anti-diabetic and anti-microbial activities for implication in therapeutic settings.


Assuntos
Anti-Inflamatórios/uso terapêutico , Naftoquinonas/uso terapêutico , Animais , Radicais Livres/metabolismo , Humanos , Oxirredução
17.
Cells ; 10(10)2021 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-34685623

RESUMO

It is generally accepted that dietary phenolics from fruits are of significant importance to human health. Unfortunately, there is minimal published data on how differences in phenolic structure(s) impact biological pathways at cellular and molecular levels. We observed that haskap berry extracts isolated with ethanol:formic acid:water or phenolic subclass fractions separated using different concentrations of ethanol (40% and 100%) impacted cell growth in a positive manner. All fractions and extracts significantly increased population doubling times. All extracts and fractions reduced intracellular free radicals; however, there were differences in these effects, indicating different abilities to scavenge free radicals. The extracts and fractions also exhibited differing impacts on transcripts encoding the antioxidant enzymes (CAT, SOD1, GPX1, GSS and HMOX1) and the phosphorylation state of nuclear factor-κB (NF-κB). We further observed that extracts and fractions containing different phenolic structures had divergent impacts on the mammalian target of rapamycin (mTOR) and sirtuin 1 (SIRT1). siRNA-mediated knockdown of SIRT1 transcripts demonstrated that this enzyme is key to eliciting haskap phenolic(s) impact on cells. We postulate that phenolic synergism is of significant importance when evaluating their dietary impact.


Assuntos
Derme/patologia , Fibroblastos/patologia , Frutas/química , Lonicera/química , Fenóis/farmacologia , Estresse Fisiológico , Antioxidantes/metabolismo , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Radicais Livres/metabolismo , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Extratos Vegetais/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirtuína 1/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fator de Transcrição RelA/metabolismo
18.
Molecules ; 26(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34641628

RESUMO

This work aims to assess the recently established anti-inflammatory and antioxidant potential of melatonin of plant origin extracted from the plant matrix as a phytomelatonin complex (PHT-MLT), and compare its activity with synthetic melatonin (SNT-MLT) when used on its own or with vitamin C. For this purpose, a COX-2 enzyme inhibitory activity test, an antiradical activity in vitro and on cell lines assays, was performed on both PHT-MLT and SNT-MLT products. COX-2 inhibitory activity of PHT-MLT was found to be ca. 6.5 times stronger than that of SNT-MLT (43.3% and 6.7% enzyme inhibition, equivalent to the activity of acetylsalicylic acid in conc. 30.3 ± 0.2 and 12.0 ± 0.3 mg/mL, respectively). Higher antiradical potential and COX-2 inhibitory properties of PHT-MLT could be explained by the presence of additional naturally occurring constituents in alfalfa, chlorella, and rice, which were clearly visible on the HPLC-ESI-QTOF-MS fingerprint. The antiradical properties of PHT-MLT determined in the DPPH test (IC50 of 21.6 ± 1 mg of powder/mL) were found to originate from the presence of other metabolites in the 50% EtOH extract while SNT-MLT was found to be inactive under the applied testing conditions. However, the antioxidant studies on HaCaT keratinocytes stimulated with H2O2 revealed a noticeable activity in all samples. The presence of PHT-MLT (12.5, 25 and 50 µg/mL) and vitamin C (12.5, 25 and 50 µg/mL) in the H2O2-pretreated HaCaT keratinocytes protected the cells from generating reactive oxygen species. This observation confirms that MLT-containing samples affect the intracellular production of enzymes and neutralize the free radicals. Presented results indicated that MLT-containing products in combination with Vitamin C dosage are worth to be considered as a preventive alternative in the therapy of various diseases in the etiopathogenesis, of which radical and inflammatory mechanisms play an important role.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Ciclo-Oxigenase 2/metabolismo , Queratinócitos/citologia , Melatonina/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Antioxidantes/síntese química , Antioxidantes/química , Ácido Ascórbico/farmacologia , Linhagem Celular , Regulação para Baixo , Sinergismo Farmacológico , Radicais Livres/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/efeitos adversos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Melatonina/síntese química , Melatonina/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
19.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638985

RESUMO

The human skin is exposed to various environmental factors including solar radiation and ambient air pollutants. Although, due to its physical and biological properties, the skin efficiently protects the body against the harm of environmental factors, their excessive levels and possible synergistic action may lead to harmful effects. Among particulate matter present in ambient air pollutants, PM2.5 is of particular importance for it can penetrate both disrupted and intact skin, causing adverse effects to skin tissue. Although certain components of PM2.5 can exhibit photochemical activity, only a limited amount of data regarding the interaction of PM2.5 with light and its effect on skin tissue are available. This study focused on light-induced toxicity in cultured human keratinocytes, which was mediated by PM2.5 obtained in different seasons. Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM) were employed to determine sizes of the particles. The ability of PM2.5 to photogenerate free radicals and singlet oxygen was studied using EPR spin-trapping and time-resolved singlet oxygen phosphorescence, respectively. Solar simulator with selected filters was used as light source for cell treatment to model environmental lightning conditions. Cytotoxicity of photoexcited PM2.5 was analyzed using MTT assay, PI staining and flow cytometry, and the apoptotic pathway was further examined using Caspase-3/7 assay and RT-PCR. Iodometric assay and JC-10 assay were used to investigate damage to cell lipids and mitochondria. Light-excited PM2.5 were found to generate free radicals and singlet oxygen in season-dependent manner. HaCaT cells containing PM2.5 and irradiated with UV-Vis exhibited oxidative stress features-increased peroxidation of intracellular lipids, decrease of mitochondrial membrane potential, enhanced expression of oxidative stress related genes and apoptotic cell death. The data indicate that sunlight can significantly increase PM2.5-mediated toxicity in skin cells.


Assuntos
Poluentes Atmosféricos/efeitos da radiação , Poluentes Atmosféricos/toxicidade , Células HaCaT/efeitos dos fármacos , Luz/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/efeitos da radiação , Material Particulado/toxicidade , Poluentes Atmosféricos/química , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Radicais Livres/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HaCaT/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/genética , Estresse Oxidativo/efeitos da radiação , Tamanho da Partícula , Material Particulado/química , Espécies Reativas de Oxigênio/metabolismo , Pele/efeitos dos fármacos , Pele/metabolismo , Envelhecimento da Pele/efeitos dos fármacos
20.
Int J Mol Sci ; 22(19)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34639139

RESUMO

Oxygen in the atmosphere is a crucial component for life-sustaining aerobic respiration in humans. Approximately 95% of oxygen is consumed as energy and ultimately becomes water; however, the remaining 5% produces metabolites called activated oxygen or reactive oxygen species (ROS), which are extremely reactive. Skin, the largest organ in the human body, is exposed to air pollutants, including diesel exhaust fumes, ultraviolet rays, food, xenobiotics, drugs, and cosmetics, which promote the production of ROS. ROS exacerbate skin aging and inflammation, but also function as regulators of homeostasis in the human body, including epidermal keratinocyte proliferation. Although ROS have been implicated in various skin diseases, the underlying mechanisms have not yet been elucidated. Current knowledge on ROS-related and oxidative stress-related skin diseases from basic research to clinical treatment strategies are discussed herein. This information may be applied to the future treatment of skin diseases through the individual targeting of the ROS generated in each case via their inhibition, capture, or regulation.


Assuntos
Radicais Livres/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Dermatopatias/patologia , Animais , Humanos , Dermatopatias/metabolismo
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