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1.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638926

RESUMO

Myo-inositol (myo-Ins) and D-chiro-inositol (D-chiro-Ins) are natural compounds involved in many biological pathways. Since the discovery of their involvement in endocrine signal transduction, myo-Ins and D-chiro-Ins supplementation has contributed to clinical approaches in ameliorating many gynecological and endocrinological diseases. Currently both myo-Ins and D-chiro-Ins are well-tolerated, effective alternative candidates to the classical insulin sensitizers, and are useful treatments in preventing and treating metabolic and reproductive disorders such as polycystic ovary syndrome (PCOS), gestational diabetes mellitus (GDM), and male fertility disturbances, like sperm abnormalities. Moreover, besides metabolic activity, myo-Ins and D-chiro-Ins deeply influence steroidogenesis, regulating the pools of androgens and estrogens, likely in opposite ways. Given the complexity of inositol-related mechanisms of action, many of their beneficial effects are still under scrutiny. Therefore, continuing research aims to discover new emerging roles and mechanisms that can allow clinicians to tailor inositol therapy and to use it in other medical areas, hitherto unexplored. The present paper outlines the established evidence on inositols and updates on recent research, namely concerning D-chiro-Ins involvement into steroidogenesis. In particular, D-chiro-Ins mediates insulin-induced testosterone biosynthesis from ovarian thecal cells and directly affects synthesis of estrogens by modulating the expression of the aromatase enzyme. Ovaries, as well as other organs and tissues, are characterized by a specific ratio of myo-Ins to D-chiro-Ins, which ensures their healthy state and proper functionality. Altered inositol ratios may account for pathological conditions, causing an imbalance in sex hormones. Such situations usually occur in association with medical conditions, such as PCOS, or as a consequence of some pharmacological treatments. Based on the physiological role of inositols and the pathological implications of altered myo-Ins to D-chiro-Ins ratios, inositol therapy may be designed with two different aims: (1) restoring the inositol physiological ratio; (2) altering the ratio in a controlled way to achieve specific effects.

2.
ACS Chem Neurosci ; 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34652128

RESUMO

A new series of pyrimidine and pyridine diamines was designed as dual binding site inhibitors of cholinesterases (ChEs), characterized by two small aromatic moieties separated by a diaminoalkyl flexible linker. Many compounds are mixed or uncompetitive acetylcholinesterase (AChE) and/or butyrylcholinesterase (BChE) nanomolar inhibitors, with compound 9 being the most active on Electrophorus electricus AChE (EeAChE) (Ki = 0.312 µM) and compound 22 on equine BChE (eqBChE) (Ki = 0.099 µM). Molecular docking and molecular dynamic studies confirmed the interaction mode of our compounds with the enzymatic active site. UV-vis spectroscopic studies showed that these compounds can form complexes with Cu2+ and Fe3+ and that compounds 18, 20, and 30 have antioxidant properties. Interestingly, some compounds were also able to reduce Aß42 and tau aggregation, with compound 28 being the most potent (22.3 and 17.0% inhibition at 100 µM on Aß42 and tau, respectively). Moreover, the most active compounds showed low cytotoxicity on a human brain cell line and they were predicted as BBB-permeable.

3.
Biomolecules ; 11(7)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34356672

RESUMO

In the search for new therapeutic strategies to contrast SARS-CoV-2, we here studied the interaction of polydatin (PD) and resveratrol (RESV)-two natural stilbene polyphenols with manifold, well known biological activities-with Spike, the viral protein essential for virus entry into host cells, and ACE2, the angiotensin-converting enzyme present on the surface of multiple cell types (including respiratory epithelial cells) which is the main host receptor for Spike binding. Molecular Docking simulations evidenced that both compounds can bind Spike, ACE2 and the ACE2:Spike complex with good affinity, although the interaction of PD appears stronger than that of RESV on all the investigated targets. Preliminary biochemical assays revealed a significant inhibitory activity of the ACE2:Spike recognition with a dose-response effect only in the case of PD.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/tratamento farmacológico , Glucosídeos/farmacologia , Resveratrol/farmacologia , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/metabolismo , Estilbenos/farmacologia , COVID-19/metabolismo , Descoberta de Drogas , Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/metabolismo
4.
Nanoscale ; 13(27): 11976-11993, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34212969

RESUMO

Though liposome-based drugs are in clinical use, the mechanism of cell internalization of liposomes is yet an object of controversy. The present experimental investigation, carried out on human glioblastoma cells, indicated different internalization routes for two diastereomeric liposomes. Molecular dynamics simulations of the lipid bilayers of the two formulations indicated that the different stereochemistry of a lipid component controls some parameters such as area per lipid molecule and fluidity of lipid membranes, surface potential and water organization at the lipid/water interface, all of which affect the interaction with biomolecules and cell components.


Assuntos
Bicamadas Lipídicas , Lipossomos , Composição de Medicamentos , Humanos , Simulação de Dinâmica Molecular , Água
5.
Biomolecules ; 11(3)2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802543

RESUMO

In this paper, the first phytochemical analysis of the ethanolic extract of Daphne sericea Vahl flowering aerial parts collected in Italy and its biological activities were reported. Eleven compounds were identified i.e., α-linolenic acid (1), tri-linoleoyl-sn-glycerol (2), pheophorbide a ethyl ester (3), pilloin (4), sinensetin (5), yuanhuanin (6), rutamontine (7), syringin (8), p-coumaric acid (9), p-anisic acid (10) and caffeic acid (11). To the best of our knowledge, compounds (1-4, 7-8 and 10) were isolated from D. sericea for the first time during this work, whereas sinensetin (5) represents a newly identified component of the entire Thymelaeaceae family. The extract was found to possess radical scavenging against both DPPH• and 2,2'-azino-bis(3-thylbenzothiazoline-6-sulfonic acid (ABTS•+) radicals, with at least a 40-fold higher potency against the latter. Moreover, chelating abilities against both ferrous and ferric ions have been highlighted, thus suggesting a possible indirect antioxidant power of the extract. Although the precise bioactive compounds remain to be discovered, the polyphenolic constituents, including phenolic acids, tannins and flavonoids, seem to contribute to the antioxidant power of the phytocomplex. In addition, the extract produced cytotoxic effects in MDA-MB-231 and U87-MG cancer cell lines, especially at the concentration of 625 µg/mL and after 48-72 h. Further studies are required to clarify the contribution of the identified compounds in the bioactivities of the extract and to support possible future applications.


Assuntos
Daphne/química , Etanol/química , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Antioxidantes/química , Itália , Thymelaeaceae/química
6.
Molecules ; 25(19)2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33036240

RESUMO

In recent decades, increasing interest in the use of natural products in anticancer therapy field has been observed, mainly due to unsolved drug-resistance problems. The antitumoral effect of natural compounds involving different signaling pathways and cellular mechanisms has been largely demonstrated in in vitro and in vivo studies. The encapsulation of natural products into different delivery systems may lead to a significant enhancement of their anticancer efficacy by increasing in vivo stability and bioavailability, reducing side adverse effects and improving target-specific activity. This review will focus on research studies related to nanostructured systems containing natural compounds for new drug delivery tools in anticancer therapies.


Assuntos
Produtos Biológicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Nanomedicina/métodos , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Produtos Biológicos/química , Humanos , Nanoestruturas/química
7.
J Fungi (Basel) ; 6(2)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545584

RESUMO

The Candida parapsilosis genome encodes for five agglutinin-like sequence (Als) cell-wall glycoproteins involved in adhesion to biotic and abiotic surfaces. The work presented here is aimed at analyzing the role of the two still uncharacterized ALS genes in C. parapsilosis, CpALS4790 and CpALS0660, by the generation and characterization of CpALS4790 and CpALS066 single mutant strains. Phenotypic characterization showed that both mutant strains behaved as the parental wild type strain regarding growth rate in liquid/solid media supplemented with cell-wall perturbing agents, and in the ability to produce pseudohyphae. Interestingly, the ability of the CpALS0660 null mutant to adhere to human buccal epithelial cells (HBECs) was not altered when compared with the wild-type strain, whereas deletion of CpALS4790 led to a significant loss of the adhesion capability. RT-qPCR analysis performed on the mutant strains in co-incubation with HBECs did not highlight significant changes in the expression levels of others ALS genes. In vivo experiments in a murine model of vaginal candidiasis indicated a significant reduction in CFUs recovered from BALB/C mice infected with each mutant strain in comparison to those infected with the wild type strain, confirming the involvement of CpAls4790 and CpAls5600 proteins in C. parapsilosis vaginal candidiasis in mice.

8.
Eur J Med Chem ; 198: 112350, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32380385

RESUMO

In order to obtain multi-functional molecules for Alzheimer's disease, a series of deferiprone derivatives has been synthesized and evaluated in vitro with the hypothesis that they can restore the cholinergic tone and attenuate the dyshomeostasis of the metals mainly involved in the pathology. These compounds were designed as dual binding site AChE inhibitors: they possess an arylalkylamine moiety connected via an alkyl chain to a 3-hydroxy-4-pyridone fragment, to allow the simultaneous interaction with catalytic active site (CAS) and peripheral anionic site (PAS) of the enzyme. Deferiprone moiety and 2-aminopyridine, 2-aminopyrimidine or 2,4-diaminopyrimidine groups have been incorporated into these compounds, in order to obtain molecules potentially able to chelate bio-metals colocalized in Aß plaques and involved in the generation of radical species. Synthesized compounds were tested by enzymatic inhibition studies towards EeAChE and eqBChE using Ellman's method. The most potent EeAChE inhibitor is compound 5a, with a Ki of 788 ± 51 nM, while the most potent eqBChE inhibitors are compounds 12 and 19, with Ki values of 182 ± 18 nM and 258 ± 25 nM respectively. Selected compounds, among the most potent cholinesterases inhibitors, were able to form complex with iron and in some cases with copper and zinc. Moreover, these compounds were characterized by low toxicity on U-87 MG Cell Line from human brain (glioblastoma astrocytoma).


Assuntos
Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/síntese química , Deferiprona/síntese química , Quelantes de Ferro/síntese química , Aminas/química , Sequência de Aminoácidos , Aminopiridinas/química , Domínio Catalítico , Inibidores da Colinesterase/farmacologia , Complexos de Coordenação/química , Deferiprona/farmacologia , Desenho de Fármacos , Humanos , Quelantes de Ferro/farmacologia , Simulação de Acoplamento Molecular , Pirimidinas/química , Relação Estrutura-Atividade
9.
Expert Opin Drug Metab Toxicol ; 16(3): 255-274, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32129111

RESUMO

Introduction: This Experts' opinion provides an updated scientific support to gynecologists, obstetricians, endocrinologists, nutritionists, neurologists and general practitioners on the use of Inositols in the therapy of Polycystic Ovary Syndrome (PCOS) and non-insulin dependent (type 2) diabetes mellitus (NIDDM).Areas covered: This paper summarizes the physiology of Myo-Inositol (MI) and D-Chiro-Inositol (DCI), two important molecules present in human organisms, and their therapeutic role, also for treating infertility. Some deep differences between the physiological functions of MI and DCI, as well as their safety and intestinal absorption are discussed. Updates include new evidence on the efficacy exerted in PCOS by the 40:1 MI/DCI ratio, and the innovative approach based on alpha-lactalbumin to overcome the decreased therapeutic efficacy of Inositols in some patients.Expert opinion: The evidence suggests that MI, alone or with DCI in the 40:1 ratio, offers a promising treatment for PCOS and NIDDM. However, additional studies need to evaluate some still unresolved issues, such as the best MI/DCI ratio for treating NIDDM, the potential cost-effectiveness of reduced gonadotropins administration in IVF due to MI treatment, or the benefit of MI supplementation in ovulation induction with clomiphene citrate in PCOS patients.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Prova Pericial , Inositol/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Reprodução/efeitos dos fármacos , Complexo Vitamínico B/uso terapêutico , Animais , Diabetes Mellitus Tipo 2/metabolismo , Prova Pericial/tendências , Feminino , Humanos , Inositol/farmacocinética , Síndrome do Ovário Policístico/metabolismo , Reprodução/fisiologia , Complexo Vitamínico B/farmacocinética
10.
Microbiol Res ; 231: 126351, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707298

RESUMO

The ability of yeast to adhere to biotic and abiotic surfaces represents an essential trait during the early stages of infection. Agglutinin-like sequence (Als) cell-wall proteins play a key role in adhesion of Candida species. Candida parapsilosis genome encompasses 5 ALS members, of which only the role of CPAR2_404800 has been elucidated. The present project was aimed at investigating the contribution of C. parapsilosis Als proteins by generating edited strains lacking functional Als proteins. CPAR2_404770 and CPAR2_404780, further indicated as CpALS4770 and CpALS4780, were selected for the generation of single and double edited strains using an episomal CRISPR/Cas9 technology. Phenotypic characterization of mutant strains revealed that editing of both genes had no impact on the in vitro growth of C. parapsilosis or on morphogenesis. Notably, CpALS4770-edited strain showed a reduction of biofilm formation and adhesive properties to human buccal cells (HBECs). Conversely, single CpALS4780-edited strain did not show any difference compared to the wild-type strain in all the assays performed, while the double CpALS4770-CpALS4780 mutant revealed an increased ability to produce biofilm, a hyper-adhesive phenotype to HBECs, and a marked tendency to form cellular aggregates. Murine vaginal infection experiments indicated a significant reduction in CFUs recovered from BALC/c mice infected with single and double edited strains, compared to those infected with the wild-type strain. These finding clearly indicate that CpAls4770 plays a role in adhesion to biotic and abiotic surfaces, while both CpALS4770 and CpALS4780 genes are required for C. parapsilosis ability to colonize and persist in the vaginal mucosa.


Assuntos
Candida parapsilosis , Adesão Celular/genética , Virulência/genética , Animais , Biofilmes/crescimento & desenvolvimento , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Candida parapsilosis/genética , Candida parapsilosis/patogenicidade , Candidíase , Técnicas de Cultura de Células , Feminino , Proteínas Fúngicas/genética , Inativação Gênica , Genes Fúngicos , Humanos , Camundongos , Membrana Mucosa/microbiologia
11.
Medicines (Basel) ; 5(4)2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-30347861

RESUMO

Since ancient times, plants have been used to preserve food, or for their health properties. Essential oils are complex mixtures of volatile compounds that are obtained from botanical material, specifically from aromatic plants. Lamiaceae is one of the most important families in the production of essential oils, as it has both antioxidant and antimicrobial properties. The essential oils of Mentha (the Lamiaceae family) have been extensively studied for their biological actions. In this review, we report the antioxidant, antifungal, antibiofilm, and cytotoxic properties of Mentha spp. essential oils. The first objective is to provide comprehensive information about the use of essential oils in the treatment of fungal infections, or as antioxidants and integrative anticancer therapy. The second is to explore the evidence supporting its effectiveness in treating diseases without causing any serious adverse reactions.

12.
Front Microbiol ; 8: 1040, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659878

RESUMO

Membrane vesicles (MVs) are bilayer structures which bleb from bacteria, and are important in trafficking biomolecules to other bacteria or host cells. There are few data about MVs produced by the Gram-positive commensal-derived probiotic Lactobacillus reuteri; however, MVs from this species may have potential therapeutic benefit. The aim of this study was to detect and characterize MVs produced from biofilm (bMVs), and planktonic (pMVs) phenotypes of L. reuteri DSM 17938. MVs were analyzed for structure and physicochemical characterization by Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). Their composition was interrogated using various digestive enzyme treatments and subsequent Transmission Electron Microscopy (TEM) analysis. eDNA (extracellular DNA) was detected and quantified using PicoGreen. We found that planktonic and biofilm of L. reuteri cultures generated MVs with a broad size distribution. Our data also showed that eDNA was associated with pMVs and bMVs (eMVsDNA). DNase I treatment demonstrated no modifications of MVs, suggesting that an eDNA-MVs complex protected the eMVsDNA. Proteinase K and Phospholipase C treatments modified the structure of MVs, showing that lipids and proteins are important structural components of L. reuteri MVs. The biological composition and the physicochemical characterization of MVs generated by the probiotic L. reuteri may represent a starting point for future applications in the development of vesicles-based therapeutic systems.

13.
Nat Prod Res ; 30(4): 412-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25782920

RESUMO

Pseudomonas syringae pv. actinidiae (PSA) is the causal agent of bacterial canker of kiwifruit. It is very difficult to treat pandemic disease. The prolonged treatment with antibiotics, has resulted in failure and resistance and alternatives to conventional antimicrobial therapy are needed. The aim of our study was to analyse the phenotypic characteristics of PSA, identify new substances from natural source i.e. essential oils (EOs) able to contain the kiwifruit canker and investigate their potential use when utilised in combination. Specially, we investigated the morphological differences of PSA isolates by scanning electron microscope, and the synergic action of different EOs by time-kill and checkerboard methods. Our results demonstrated that PSA was able to produce extracellular polysaccharides when it was isolated from trunk, and, for the first time, that it was possible to kill PSA with a mixture of EOs after 1 h of exposition. We hypothesise on its potential use in agriculture.


Assuntos
Antibacterianos/farmacologia , Óleos Voláteis/farmacologia , Pseudomonas syringae/efeitos dos fármacos , Actinidia/microbiologia , Sinergismo Farmacológico , Frutas , Cinética , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Doenças das Plantas/microbiologia
14.
J Biomater Sci Polym Ed ; 27(1): 69-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26468979

RESUMO

The synthesis and the characterization of three new naproxen decorated polymers are described. A versatile and general approach is employed to link the drug to polymers, affording the derivatives with a very high degree of purity. The release of the drug from the conjugates proved to be exceptionally slow, even in acidic aqueous media, and the kinetic of the process seems to be triggered by their solubility in water. On the other hand, the interesting outcome of the first ex vivo drug release experiments on human blood samples makes this preliminary study valuable for future investigations on the use of these polymeric prodrugs in in vivo treatment of inflammatory states.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Naproxeno/química , Polímeros/química , Pró-Fármacos/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Solubilidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Água/química
15.
Biochim Biophys Acta ; 1848(11 Pt A): 2868-77, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26325345

RESUMO

Saliva contains hundreds of small proline-rich peptides most of which derive from the post-translational and post-secretory processing of the acidic and basic salivary proline-rich proteins. Among these peptides we found that a 20 residue proline-rich peptide (p1932), commonly present in human saliva and patented for its antiviral activity, was internalized within cells of the oral mucosa. The cell-penetrating properties of p1932 have been studied in a primary gingival fibroblast cell line and in a squamous cancer cell line, and compared to its retro-inverso form. We observed by mass-spectrometry, flow cytometry and confocal microscopy that both peptides were internalized in the two cell lines on a time scale of minutes, being the natural form more efficient than the retro-inverso one. The cytosolic localization was dependent on the cell type: both peptide forms were able to localize within nuclei of tumoral cells, but not in the nuclei of gingival fibroblasts. The uptake was shown to be dependent on the culture conditions used: peptide internalization was indeed effective in a complete medium than in a serum-free one allowing the hypothesis that the internalization could be dependent on the cell cycle. Both peptides were internalized likely by a lipid raft-mediated endocytosis mechanism as suggested by the reduced uptake in the presence of methyl-ß-cyclodextrin. These results suggest that the natural peptide may play a role within the cells of the oral mucosa after its secretion and subsequent internalization. Furthermore, lack of cytotoxicity of both peptide forms highlights their possible application as novel drug delivery agents.


Assuntos
Peptídeos Penetradores de Células/metabolismo , Endocitose/fisiologia , Peptídeos/metabolismo , Proteínas Salivares Ricas em Prolina/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/farmacocinética , Peptídeos Penetradores de Células/farmacologia , Células Cultivadas , Meios de Cultura/farmacologia , Meios de Cultura Livres de Soro/farmacologia , Endocitose/efeitos dos fármacos , Fibroblastos/metabolismo , Citometria de Fluxo , Gengiva/citologia , Humanos , Microscopia Confocal , Peptídeos/farmacocinética , Peptídeos/farmacologia , Proteínas Salivares Ricas em Prolina/farmacocinética , Proteínas Salivares Ricas em Prolina/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , beta-Ciclodextrinas/farmacologia
16.
Ann Ist Super Sanita ; 51(1): 62-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25857386

RESUMO

INTRODUCTION: Escherichia coli O157:H7 possesses one chromosomal and two prophagic sodC genes encoding for Cu,Zn superoxide dismutases. We evaluated the contribution of sodC genes in biofilm formation and its resistance to hydrogen peroxide. METHODS: The biofilm of sodC deletion mutants has been studied, in presence or absence of hydrogen peroxide, by crystal violet in 96-well plates and Scanning Electron Microscopy on glass coverslips. RESULTS: Deletion of prophagic sodC genes had no effect on biofilm construction, in contrast to the chromosomal gene deletion. Hydrogen peroxide treatment showed higher cell mortality and morphological alterations in sodC deletion mutants respect to wild type. These effects were related to the biofilm development stage. CONCLUSION: The role of the three SodCs is not redundant in biofilm formation and the resistance to oxidative damage. The stage of biofilm development is a crucial factor for an effective sanitization.


Assuntos
Anti-Infecciosos Locais/farmacologia , Biofilmes/efeitos dos fármacos , Cromossomos Bacterianos/genética , Escherichia coli O157/genética , Proteínas de Escherichia coli/genética , Peróxido de Hidrogênio/farmacologia , Prófagos/genética , Superóxido Dismutase/genética , Deleção de Genes
17.
Free Radic Biol Med ; 81: 88-99, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25591967

RESUMO

The uptake of spermine into mammalian mitochondria indicated the need to identify its catabolic pathway in these organelles. Bovine liver mitochondria were therefore purified and their capacity for natural polyamine uptake was verified. A kinetic approach was then used to determine the presence of an MDL 72527-sensitive enzyme with spermine oxidase activity in the matrix of bovine liver mitochondria. Western blot analysis of mitochondrial fractions and immunogold electron microscopy observations of purified mitochondria unequivocally confirmed the presence of a protein recognized by anti-spermine oxidase antibodies in the mitochondrial matrix. Preliminary kinetic characterization showed that spermine is the preferred substrate of this enzyme; lower activity was detected with spermidine and acetylated polyamines. Catalytic efficiency comparable to that of spermine was also found for 1-aminododecane. The considerable effect of ionic strength on the Vmax/KM ratio suggested the presence of more than one negatively charged zone inside the active site cavity of this mitochondrial enzyme, which is probably involved in the docking of positively charged substrates. These findings indicate that the bovine liver mitochondrial matrix contains an enzyme belonging to the spermine oxidase class. Because H2O2 is generated by spermine oxidase activity, the possible involvement of the latter as an important signaling transducer under both physiological and pathological conditions should be considered.


Assuntos
Fígado/enzimologia , Mitocôndrias Hepáticas/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Espermina/metabolismo , Animais , Domínio Catalítico , Bovinos , Peróxido de Hidrogênio/metabolismo , Cinética , Concentração Osmolar , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/isolamento & purificação , Putrescina/análogos & derivados , Putrescina/química , Espermidina/metabolismo , Eletricidade Estática , Especificidade por Substrato
18.
Langmuir ; 31(1): 76-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25496076

RESUMO

Anthraquinone compound aloe-emodin (AE) has shown antineoplastic, antibacterial, antiviral, and anti-inflammatory properties and scavenging activity on free radicals. Because of these therapeutic features, AE has been attracting increasing interest and could be applied in the curing of many diseases. However, until now the physicochemical features of this compound have not been fully investigated; furthermore, its wide application might be hindered by its scarce solubility in aqueous media (∼19 µM). The inclusion of AE in nanocarriers, such as cationic liposomes, could allow its delivery effectively and selectively to target sites, reducing side effects in the remaining tissues. In this work, the weak acid nature of AE, because of its two phenolic functions, was exploited to load it remotely in the internal aqueous phase of liposomes in response to a difference in pH between the inside and outside of the liposomes, pHin > pHout. The inclusion of AE in gemini-based cationic liposomes by the acetate gradient method was obtained at high AE/lipid ratios (up to 1:30).


Assuntos
Antraquinonas/química , Lipossomos/química , Compostos de Amônio Quaternário/química , Concentração de Íons de Hidrogênio , Membranas Artificiais , Água/química
19.
PLoS One ; 9(6): e98387, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24896636

RESUMO

Currently available therapies for candidiasis are based on antifungal drugs belonging to azole and echinocandin families that interfere with different aspects of fungal metabolism. These drugs, beyond their specific effects, elicit also a cellular stress including an unbalance of redox state that is counteracted not only utilizing antioxidant species but also increasing the outcome export by transporters to detoxify the internal environment. These cellular actions are both based on the cytosolic concentration of reduced glutathione (GSH). In this paper we investigated the effects of two antifungal drugs fluconazole and micafungin on the redox state of the cell in C. albicans to understand if the resistance to these drugs is accompanied by variation of glutathione metabolism. Analyses of resistant strains showed a marked difference in glutathione contents in strains resistant to fluconazole (CO23RFLC) or micafungin (CO23RFK). In CO23RFLC, the total amount of glutathione was more than doubled with respect to CO23RFK thanks to the increased activity of γ-glutamilcysteine synthetase, the key enzyme involved in GSH synthesis. We demonstrated that the GSH increase in CO23RFLC conferred to this strain a clear advantage in counteracting oxidative toxic agents while assignment of other roles, such as a more efficient elimination of the drug from the cell, should be considered more speculative. As far as MCFG resistance is concerned, from our data a role of glutathione metabolism in supporting this condition is not evident. Overall our data indicate that glutathione metabolism is differently affected in the two resistant strains and that glutathione system may play an important role in the global organization of C.albicans cells for resistance to fluconazole. Such scenario may pave the way to hypothesize the use of oxidant drugs or inhibitors able to deplete reduced glutathione level as a novel approach, for counteracting the resistance to this specific antifungal drug.


Assuntos
Antifúngicos/farmacologia , Candida albicans/metabolismo , Farmacorresistência Fúngica/fisiologia , Equinocandinas/farmacologia , Fluconazol/farmacologia , Glutationa/metabolismo , Lipopeptídeos/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Micafungina , Testes de Sensibilidade Microbiana , Oxirredução
20.
Artigo em Inglês | MEDLINE | ID: mdl-24719638

RESUMO

Candidosis is the most important cause of fungal infections in humans. The yeast Candida albicans can form biofilms, and it is known that microbial biofilms play an important role in human diseases and are very difficult to treat. The prolonged treatment with drugs has often resulted in failure and resistance. Due to the emergence of multidrug resistance, alternatives to conventional antimicrobial therapy are needed. This study aims to analyse the effects induced by essential oil of Mentha suaveolens Ehrh (EOMS) on Candida albicans and its potential synergism when used in combination with conventional drugs. Morphological differences between control and EOMS treated yeast cells or biofilms were observed by scanning electron microscopy and transmission electron microscopy (SEM and TEM resp.,). In order to reveal the presence of cell cycle alterations, flow cytometry analysis was carried out as well. The synergic action of EOMS was studied with the checkerboard method, and the cellular damage induced by different treatments was analysed by TEM. The results obtained have demonstrated both the effects of EOMS on C. albicans yeast cells and biofilms and the synergism of EOMS when used in combination with conventional antifungal drugs as fluconazole (FLC) and micafungin (MCFG), and therefore we can hypothesize on its potential use in therapy. Further studies are necessary to know its mechanism of action.

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