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1.
J Enzyme Inhib Med Chem ; 38(1): 2274798, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905438

RESUMO

Type 2 diabetes (T2D) is a progressive metabolic disorder of glucose metabolism. One of the therapeutic approaches for the treatment of T2D is reducing postprandial hyperglycaemia through inhibition of the digestive enzymes α-glucosidase and α-amylase. In this context, aimed at identifying natural products endowed with anti-T2D potential, we focused on Ptilostemon casabonae (L.) Greuter, a species belonging to Asteraceae family. Enzymatic inhibition, antioxidant activity, phenolic composition and cellular assays were performed. This study revealed that the P. casabonae hydroalcoholic extract exerts a potent inhibitory activity against α-glucosidase. This activity is supported by an antioxidant effect, preventing ROS formation in a stressed cellular system. HPLC-PDA-MS/MS analysis, revealed a complex polyphenolic fraction. Among the tested pure compounds, 1,5-dicaffeoylquinic acid, apigenin and rutin displayed good α-glucosidase inhibitory activity. Our study suggested new potential of P. casabonae encouraging us to further testing the possible therapeutic potential of this extract.


Assuntos
Asteraceae , Diabetes Mellitus Tipo 2 , Diabetes Mellitus Tipo 2/tratamento farmacológico , Antioxidantes/farmacologia , Hipoglicemiantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Glucosidases/metabolismo , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , alfa-Amilases/metabolismo
2.
Molecules ; 28(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985617

RESUMO

A comparative in vitro study of the antioxidant potential of natural phenols (zingerone, curcumin, raspberry ketone, magnolol) and their synthesized derivatives was performed. The antioxidant efficiency was evaluated in blood serum obtained from healthy individuals, by means of spectrophotometry, before and after the addition of pro-oxidant tert-butyl hydroperoxide (TBH). Moreover, the antioxidant effect of an equimolar mixture of curcumin and zingerone was investigated. Interpretation of our results reveals that in the blood serum of healthy individuals curcumin (C1), raspberry ketone (RK1), magnolol (M1) and synthesized derivative of zingerone (Z2) demonstrate remarkable antioxidant effects (p < 0.05). However, in the state of TBH-induced excessive oxidative stress natural magnolol and synthesized derivatives C1, Z1 and RK1 show powerful antioxidant activity and thus can be further investigated to obtain information about their metabolic transformations and their potential influence at the cellular level. Results obtained from measurements in an equimolar mixture of zingerone and curcumin indicate synergism (p < 0.05) between the two compounds. This combination is especially successful due to the fast and efficient neutralization of added pro-oxidant TBH. The commercial availability of turmeric and ginger and their frequent combined use in diet suggest ideas for further broader utilization of the beneficial synergistic effect of their phenolic components.


Assuntos
Antioxidantes , Curcumina , Humanos , Antioxidantes/farmacologia , Fenóis , Curcumina/farmacologia , Espécies Reativas de Oxigênio
3.
Int J Mol Sci ; 23(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35682928

RESUMO

The tyrosinase enzyme, which catalyzes the hydroxylation of monophenols and the oxidation of o-diphenols, is typically involved in the synthesis of the dark product melanin starting from the amino acid tyrosine. Contributing to the browning of plant and fruit tissues and to the hyperpigmentation of the skin, leading to melasma or age spots, the research of possible tyrosinase inhibitors has attracted much interest in agri-food, cosmetic, and medicinal industries. In this study, we analyzed the capability of antamanide, a mushroom bioactive cyclic decapeptide, and some of its glycine derivatives, compared to that of pseudostellarin A, a known tyrosinase inhibitor, to hinder tyrosinase activity by using a spectrophotometric method. Additionally, computational docking studies were performed in order to elucidate the interactions occurring with the tyrosinase catalytic site. Our results show that antamanide did not exert any inhibitory activity. On the contrary, the three glycine derivatives AG9, AG6, and AOG9, which differ from each other by the position of a glycine that substitutes phenylalanine in the parent molecule, improving water solubility and flexibility, showed tyrosinase inhibition by spectrophotometric assays. Analytical data were confirmed by computational studies.


Assuntos
Agaricales , Monofenol Mono-Oxigenase , Agaricales/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Glicina/farmacologia , Melaninas/metabolismo , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/metabolismo , Peptídeos Cíclicos
4.
Molecules ; 27(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35164192

RESUMO

Monoamine oxidases (MAOs) are attractive targets in drug design. The inhibition of one of the isoforms (A or B) is responsible for modulating the levels of different neurotransmitters in the central nervous system, as well as the production of reactive oxygen species. Molecules that act selectively on one of the MAO isoforms have been studied deeply, and coumarin has been described as a promising scaffold. In the current manuscript we describe a comparative study between 3-phenylcoumarin (endo coumarin-resveratrol-inspired hybrid) and trans-6-styrylcoumarin (exo coumarin-resveratrol-inspired hybrid). Crystallographic structures of both compounds were obtained and analyzed. 3D-QSAR models, in particular CoMFA and CoMSIA, docking simulations and molecular dynamics simulations have been performed to support and better understand the interaction of these molecules with both MAO isoforms. Both molecules proved to inhibit MAO-B, with trans-6-styrylcoumarin being 107 times more active than 3-phenylcoumarin, and 267 times more active than trans-resveratrol.


Assuntos
Cumarínicos/química , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/efeitos dos fármacos , Resveratrol/química , Estirenos/química , Domínio Catalítico , Simulação de Acoplamento Molecular
5.
Molecules ; 27(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432043

RESUMO

Tyrosinase is a well-known copper-containing metalloenzyme typically involved in the synthesis of melanin. Recently, curcumin and several synthetic derivatives have been recognized as tyrosinase inhibitors with interesting anti-melanogenic therapeutic activity. In this study, three curcumin-inspired compounds 1, 6 and 7 were prepared in yields ranging from 60 to 88 % and spectrophotometric, electrochemical, in vitro and in silico analyses were carried out. The viability of PC12 cells, a rat pheochromocytoma derived-cell line, with compounds 1, 6 and 7, showed values around 80% at 5 µM concentration. In cell proliferation assays, compounds 1, 6 and 7 did not show significant toxicity on fibroblasts nor melanoma cells up to 10 µM with viability values over 90%. The inhibition of tyrosinase activity was evaluated both by a UV-Vis spectroscopic method at two different concentrations, 0.2 and 2.0 µM, and by amperometric assay with IC50 for compounds 1, 6 and 7 ranging from 11 to 24 nM. Melanin content assays on human melanoma cells were performed to test the capability of compounds to inhibit melanin biosynthesis. All compounds exerted a decrease in melanin content, with compound 7 being the most effective by showing a melanogenesis inhibition up to four times greater than arbutin at 100 µM. Moreover, the antioxidant activity of the selected inhibitors was evaluated against H2O2 in amperometric experiments, whereby compound 7 was about three times more effective compared to compounds 1 and 6. The tyrosinase X-ray structure of Bacterium megaterium crystal was used to carry out molecular docking studies in the presence of compounds 1, 6 and 7 in comparison with that of kojic acid and arbutin, two conventional tyrosinase inhibitors. Molecular docking of compounds 6 and 7 confirmed the high affinity of these compounds to tyrosinase protein.


Assuntos
Curcumina , Monofenol Mono-Oxigenase , Humanos , Animais , Ratos , Curcumina/farmacologia , Melaninas , Arbutina , Simulação de Acoplamento Molecular , Peróxido de Hidrogênio
6.
Rapid Commun Mass Spectrom ; 35(11): e9082, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33733542

RESUMO

RATIONALE: 3-Aroylbenzofurans and their 2-nitrophenyl derivatives constitute fundamental intermediates for the synthesis of target compounds with pharmaceutical properties. However, their preparation via the Friedel-Crafts acylation of 2-phenylbenzofurans, using Lewis acid as catalyst, often leads to mixtures of regioisomeric aroylbenzofurans that can be challenging to distinguish, thus preventing the reaction characterization. METHOD: We report a method for the unambiguous identification and differentiation of the desired 3-benzoyl isomers from their 4- and 6-regioisomers in a crude reaction mixture using gas chromatography coupled to multiple-stage mass spectrometric (GC/MSn ) analysis performed in collision-induced dissociation (CID) mode. RESULTS: Upon electron ionization, each set of isomers displayed nearly identical mass spectra. MSn revealed fragmentation patterns that varied in the location of the benzoyl group on the benzofuran scaffold: CID experiments performed on the molecular ion allowed the distinction of the 3-acyl isomers from the 4- and 6-regioisomers; CID experiments on the [M - Ar]+ ion allowed the distinction of the 4-benzoyl from the 6-benzoyl regioisomer, when the nitro group is located on the 2-phenyl ring. Moreover, the unusual loss of OH• radical allowed ascertaining the position of the nitro group in 3-acyl regioisomers bearing the NO2 group. The origin of the diagnostic OH• loss was investigated through MSn experiments using 18 O-labelled 3-benzoyl derivatives. CONCLUSIONS: The method allows the rapid characterization of crude reaction mixtures of benzoylbenzofurans using solely GC/MSn analysis, simplifying the workflow of extensive isolation and purification for structure elucidation.

7.
Bioorg Chem ; 107: 104616, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33444985

RESUMO

A new series of 2-phenylbenzofuran derivatives were designed and synthesized to determine relevant structural features for the MAO inhibitory activity and selectivity. Methoxy substituents were introduced in the 2-phenyl ring, whereas the benzofuran moiety was not substituted or substituted at the positions 5 or 7 with a nitro group. Substitution patterns on both the phenyl ring and the benzofuran moiety determine the affinity for MAO-A or MAO-B. The 2-(3-methoxyphenyl)-5-nitrobenzofuran 9 was the most potent MAO-B inhibitor (IC50 = 0.024 µM) identified in this series, whereas 7-nitro-2-phenylbenzofuran 7 was the most potent MAO-A inhibitor (IC50 = 0.168 µM), both acting as reversible inhibitors. The number and position of the methoxyl groups on the 2-phenyl ring, have an important influence on the inhibitory activity. Molecular docking studies confirmed the experimental results and highlighted the importance of key residues in enzyme inhibition.


Assuntos
Benzofuranos/química , Inibidores da Monoaminoxidase/síntese química , Monoaminoxidase/química , Benzofuranos/metabolismo , Benzofuranos/farmacologia , Sítios de Ligação , Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Estrutura Terciária de Proteína , Relação Estrutura-Atividade
8.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073232

RESUMO

Melanoma, the deadliest form of skin cancer, is still one of the most difficult cancers to treat despite recent advances in targeted and immune therapies. About 50% of advanced melanoma do not benefit of such therapies, and novel treatments are requested. Curcumin and its analogs have shown good anticancer properties and are being considered for use in combination with or sequence to recent therapies to improve patient outcomes. Our group previously published the synthesis and anticancer activity characterization of a novel curcumin-related compound against melanoma and neuroblastoma cells (D6). Here, two hydroxylated biphenyl compounds-namely, compounds 11 and 12-were selected among a small collection of previously screened C2-symmetric hydroxylated biphenyls structurally related to D6 and curcumin, showing the best antitumor potentiality against melanoma cells (IC50 values of 1.7 ± 0.5 µM for 11 and 2.0 ± 0.7 µM for 12) and no toxicity of normal fibroblasts up to 32 µM. Their antiproliferative activity was deeply characterized on five melanoma cell lines by performing dose-response and clonal growth inhibition assays, which revealed long-lasting and irreversible effects for both compounds. Apoptosis induction was ascertained by the annexin V and TUNEL assays, whereas Western blotting showed caspase activation and PARP cleavage. A cell cycle analysis, following cell treatments with either compound 11 or 12, highlighted an arrest in the G2/M transition. Taking all this evidence together, 11 and 12 were shown to be good candidates as lead compounds to develop new anticancer drugs against malignant melanoma.


Assuntos
Antineoplásicos , Apoptose/efeitos dos fármacos , Compostos de Bifenilo , Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Melanoma/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Relação Estrutura-Atividade , Melanoma Maligno Cutâneo
9.
Molecules ; 26(3)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513915

RESUMO

Onychomycosis is a common nail infection mainly caused by species belonging to the F. oxysporum, F. solani, and F. fujikuroi species complexes. The aim of this study was to evaluate the in vitro susceptibility of six representative strains of clinically relevant Fusarium spp. toward a set of natural-occurring hydroxycinnamic acids and their derivatives with the purpose to develop naturally occurring products in order to cope with emerging resistance phenomena. By introducing a prenylated chain at one of the hydroxy groups of trans-cinnamic acids 1-3, ten prenylated derivatives (coded 4-13) were preliminarily investigated in solid Fusarium minimal medium (FMM). Minimal inhibitory concentration (MIC) and lethal dose 50 (LD50) values were then determined in liquid FMM for the most active selected antifungal p-coumaric acid 3,3'-dimethyl allyl ester 13, in comparison with the conventional fungicides terbinafine (TRB) and amphotericin B (AmB), through the quantification of the fungal growth. Significant growth inhibition was observed for prenylated derivatives 4-13, evidencing ester 13 as the most active. This compound presented MIC and LD50 values (62-250 µM and 7.8-125 µM, respectively) comparable to those determined for TRB and AmB in the majority of the tested pathogenic strains. The position and size of the prenylated chain and the presence of a free phenol OH group appear crucial for the antifungal activity. This work represents the first report on the activity of prenylated cinnamic esters and ethers against clinical Fusarium spp. and opens new avenues in the development of alternative antifungal compounds based on a drug repositioning strategy.


Assuntos
Anti-Infecciosos/farmacologia , Produtos Biológicos/farmacologia , Ésteres/farmacologia , Éteres/farmacologia , Fusarium/efeitos dos fármacos , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Reposicionamento de Medicamentos/métodos , Fusariose/tratamento farmacológico , Fusariose/microbiologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Onicomicose/tratamento farmacológico , Onicomicose/microbiologia , Terbinafina/farmacologia
10.
Arch Insect Biochem Physiol ; 104(3): e21669, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32190926

RESUMO

Drosophila suzukii Matsumura (Diptera: Drosophilidae) is an invasive, destructive crop pest that originated in South East Asia. D. suzukii recently invaded Western countries and is threatening both European and American fruit industries. It is extremely attracted to otherwise undamaged, ripening fruits, unlike most other Drosophila species that attack only decaying or rotten fruits. Recent studies on different insect species showed that several naturally occurring compounds of easy market availability showing deterrent action may be used to supplement mass catches with food traps. Based on these considerations, the aim of the present work was to test the effects of some natural compounds (alone or in the mixture) on the olfactory system of the D. suzukii and the behavioral responses evoked. We measured by electroantennogram (EAG) recordings, the olfactory sensitivity of antennae to increasing concentrations of eugenol, vanillin, menthol, cis-jasmone; eugenol + vanillin, +menthol, +cis-jasmone; vanillin + menthol, +cis-jasmone. In addition, the behavioral responses to the same compounds and mixtures were evaluated. Our electrophysiological results show a dose-response relationship between the EAG amplitudes and the increasing concentrations of the olfactory compound. The behavioral results show that the number of laid eggs is significantly different between the standard diet and the standard diet + natural compound. These results underline a specificity in the olfactory sensitivity and in the ovipositing behavior of D. suzukii females; also, they could be valuable for the identification of key chemicals aimed at the future development of strategies in the management and control of this harmful insect for crops.


Assuntos
Drosophila/efeitos dos fármacos , Oviposição/efeitos dos fármacos , Olfato , Animais , Antenas de Artrópodes/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Benzaldeídos , Ciclopentanos , Relação Dose-Resposta a Droga , Drosophila/fisiologia , Fenômenos Eletrofisiológicos , Eugenol , Comportamento Alimentar , Feminino , Repelentes de Insetos , Mentol , Odorantes , Oxilipinas
11.
Molecules ; 25(11)2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32545293

RESUMO

The impaired activity of tyrosinase and laccase can provoke serious concerns in the life cycles of mammals, insects and microorganisms. Investigation of inhibitors of these two enzymes may lead to the discovery of whitening agents, medicinal products, anti-browning substances and compounds for controlling harmful insects and bacteria. A small collection of novel reversible tyrosinase and laccase inhibitors with a phenylpropanoid and hydroxylated biphenyl core was prepared using naturally occurring compounds and their activity was measured by spectrophotometric and electrochemical assays. Biosensors based on tyrosinase and laccase enzymes were constructed and used to detect the type of protein-ligand interaction and half maximal inhibitory concentration (IC50). Most of the inhibitors showed an IC50 in a range of 20-423 nM for tyrosinase and 23-2619 nM for laccase. Due to the safety concerns of conventional tyrosinase and laccase inhibitors, the viability of the new compounds was assayed on PC12 cells, four of which showed a viability of roughly 80% at 40 µM. In silico studies on the crystal structure of laccase enzyme identified a hydroxylated biphenyl bearing a prenylated chain as the lead structure, which activated strong and effective interactions at the active site of the enzyme. These data were confirmed by in vivo experiments performed on the insect model Tenebrio molitur.


Assuntos
Inibidores Enzimáticos/síntese química , Lacase/química , Monofenol Mono-Oxigenase/química , Fenol/química , Propanóis/síntese química , Tenebrio/crescimento & desenvolvimento , Animais , Domínio Catalítico , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Hidroxilação , Lacase/antagonistas & inibidores , Lacase/metabolismo , Modelos Moleculares , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Células PC12 , Propanóis/química , Propanóis/farmacologia , Conformação Proteica , Ratos , Tenebrio/efeitos dos fármacos , Tenebrio/enzimologia
12.
Bioorg Chem ; 84: 302-308, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30529848

RESUMO

We have designed, synthesized and evaluated a series of hydroxylated 2-phenylbenzofuran derivatives as potential cholinesterase inhibitors. Starting from a series of 2-phenylbenzofurans previously published, in this paper we present a complete synthesis and the influence on the activity of one or two hydroxyl groups located in meta or in meta and para positions respectively of the 2-phenyl ring and highlight the importance of position of hydroxyl groups. Moreover, simultaneous introduction of halogen at position 7 of the benzofuran scaffold resulted in an improved inhibitory activity against the enzyme. To further provide molecular insight and to identify the most probable ligand-binding site of the protein, docking studies were performed for the top-ranked compounds. Docking results revealed conserved ligand-binding residues and supported the role of catalytic site residues in enzyme inhibition.


Assuntos
Acetilcolinesterase/metabolismo , Benzofuranos/química , Inibidores da Colinesterase/síntese química , Acetilcolinesterase/química , Benzofuranos/metabolismo , Sítios de Ligação , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Domínio Catalítico , Inibidores da Colinesterase/metabolismo , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
13.
Sensors (Basel) ; 19(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141953

RESUMO

A preliminary assessment of properties of the commercial product Chemiplus 2DS HB (BI-QEM Specialties SpA) is proposed. Cyclic voltammetry of this oligomer containing sulfate/sulfone groups shows a single oxidative peak at +0.866 V vs. Ag/AgCl, and its passivating process on Pt electrode suggests the formation of a non-conductive layer. Electrode modification was achieved by exploiting the constant potential amperometry setting potential at +0.900 V vs. Ag/AgCl. A substantial change in the oxidative currents from electroactive species H2O2 and ascorbic acid (AA) were observed on Pt/Chemiplus 2DS HB sensors compared to unmodified Pt. Furthermore, the influence of different storage conditions on modified sensors was examined. A storage solution containing AA concentration from 0.1 until 10 mM maintained effective AA rejection of Pt/Chemiplus 2DS HB after 7 days from construction; H2O2 oxidation capability was also retained. Sulfone and sulfonate groups of Chemiplus 2DS HB are likely responsible for the dimensionality of the film and the electrostatic interaction leading to a self-blocking/self-rejection of AA. The way Pt/Chemiplus can reveal the AA presence depends on the maintaining of AA rejection, and this peculiarity can distinguish it from other sensors or biosensors.

14.
J Sci Food Agric ; 98(3): 1079-1087, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28722756

RESUMO

BACKGROUND: Traditionally, globe artichoke cultivation in the Mediterranean basin is based on monoculture and on use of high amounts of nitrogen fertiliser. This raises issues regarding its compatibility with sustainable agriculture. We studied the effect of one typical conventional (CONV) and two alternative cropping systems [globe artichoke in sequence with French bean (NCV1), or in biannual rotation (NCV2) with cauliflower and with a leguminous cover crop in inter-row spaces] on yield, polyphenol and mineral content of globe artichoke heads over two consecutive growing seasons. RESULTS: NCV2 showed statistical differences in terms of fresh product yield with respect to the monoculture systems. In addition, the dihydroxycinnamic acids and dicaffeoylquinic acids of non-conventional samples were one-fold significantly higher than the conventional one. All the samples reported good mineral content, although NCV2 achieved a higher Fe content than conventional throughout the two seasons. After two and three dates of sampling, the CONV samples showed the highest levels of K content. CONCLUSION: In our study, an acceptable commercial yield and quality of 'Spinoso sardo' were achieved by shifting the common conventional agronomic management to more sustainable ones, by means of an accurate choice of cover crop species and rotations introduced in the systems. © 2017 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Cynara scolymus/química , Cynara scolymus/crescimento & desenvolvimento , Brassica/crescimento & desenvolvimento , Fabaceae/crescimento & desenvolvimento , Minerais/análise , Polifenóis/química
15.
Bioorg Med Chem Lett ; 26(9): 2308-13, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26995529

RESUMO

A series of 2-phenylbenzofurans compounds was designed, synthesized and evaluated as cholinesterase inhibitors. The biological assay experiments showed that most of the compounds displayed a clearly selective inhibition for butyrylcholinesterase (BChE), while a weak or no effect towards acetylcholinesterase (AChE) was detected. Among these benzofuran derivatives, compound 16 exhibited the highest BChE inhibition with an IC50 value of 30.3 µM. This compound was found to be a mixed-type inhibitor as determined by kinetic analysis. Moreover, molecular dynamics simulations revealed that compound 16 binds to both the catalytic anionic site (CAS) and peripheral anionic site (PAS) of BChE and it displayed the best interaction energy value, in agreement with our experimental data.


Assuntos
Benzofuranos/síntese química , Benzofuranos/farmacologia , Butirilcolinesterase/efeitos dos fármacos , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Benzofuranos/química , Inibidores da Colinesterase/química , Modelos Moleculares
16.
Analyst ; 140(10): 3607-15, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25857616

RESUMO

Amperometric biosensors are often coated with a polymeric permselective film to avoid electroactive interference by reducing agents present in the target medium. Phenylenediamine and phenol monomers are commonly used to form these permselective films in the design of microsensors and biosensors. This paper aims to evaluate the permselectivity, stability and lifetime of polymers electrosynthesized using either constant potential amperometry (CPA) or cyclic voltammetry (CV) from naturally occurring phenylpropanoids in monomeric and dimeric forms (eugenol, isoeugenol, dehydrodieugenol and magnolol). Sensors were characterized by scanning electron microscopy and permselectivity analysis. Magnolol formed an electro-deposited polymer with a more defined three-dimensional texture in comparison with the other films. The phenol-derived films showed different permselectivity towards H2O2 over ascorbic acid and dopamine, likely to be related to the thickness and compactness of the polymer. The CV-derived films had a better permselectivity compared to the CPA-corresponding polymers. Based on these results, the permselectivity, stability and lifetime of a biosensor for glucose were studied when a magnolol coating was electro-deposited. The structural principles governing the permselectivity of the magnolol-derived film are suggested to be mainly related to the conformational flexibility of this monomer. Newly designed biosensors, coated with electropolymerized natural phenol derivatives, may represent promising analytical devices for different application fields.


Assuntos
Técnicas Biossensoriais/métodos , Fenóis/química , Polimerização , Polímeros/química , Técnicas Biossensoriais/instrumentação , Eletroquímica , Eletrodos , Glucose/análise , Glucose/química , Peróxido de Hidrogênio/química , Irídio/química , Fenilenodiaminas/química , Platina/química , Fatores de Tempo
17.
Lett Drug Des Discov ; 12(2): 131-139, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26074750

RESUMO

A small collection of eugenol- and curcumin-analog hydroxylated biphenyls was prepared by straightforward methods starting from natural 4-substituted-2-methoxyphenols and their antitumoral activity was evaluated in vitro. Two curcumin-biphenyl derivatives showed interesting growth inhibitory activities on different malignant melanoma cell lines with IC50 ranging from 13 to 1 µM. Preliminary molecular modeling studies were carried out to evaluate conformations and dihedral angles suitable for antiproliferative activity in hydroxylated biphenyls bearing a side aliphatic chain.

18.
Beilstein J Org Chem ; 11: 1398-411, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26425195

RESUMO

This study compares the ability to scavenge different peroxyl radicals and to act as chain-breaking antioxidants of monomers related to curcumin (1): dehydrozingerone (2), zingerone (3), (2Z,5E)-ethyl 2-hydroxy-6-(4-hydroxy-3-methoxyphenyl)-4-oxohexa-2,5-dienoate (4), ferulic acid (5) and their corresponding C 2-symmetric dimers 6-9. Four models were applied: model 1 - chemiluminescence (CL) of a hydrocarbon substrate used for determination of the rate constants (k A) of the reactions of the antioxidants with peroxyl radicals; model 2 - lipid autoxidation (lipidAO) used for assessing the chain-breaking antioxidant efficiency and reactivity; model 3 - oxygen radical absorbance capacity (ORAC), which yields the activity against peroxyl radicals generated by an azoinitiator; model 4 - density functional theory (DFT) calculations at UB3LYP/6-31+G(d,p) level, applied to explain the structure-activity relationship. Dimers showed 2-2.5-fold higher values of k A than their monomers. Model 2 gives information about the effects of the side chains and revealed much higher antioxidant activity for monomers and dimers with α,ß-unsaturated side chains. Curcumin and 6 in fact are dimers of the same monomer 2. We conclude that the type of linkage between the two "halves" by which the molecule is made up does not exert influence on the antioxidant efficiency and reactivity of these two dimers. The dimers and the monomers demonstrated higher activity than Trolox (10) in aqueous medium (model 3). A comparison of the studied compounds with DL-α-tocopherol (11), Trolox and curcumin is made. All dimers are characterized through lower bond dissociation enthalpies (BDEs) than their monomers (model 4), which qualitatively supports the experimental results.

19.
Nutrients ; 16(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38892571

RESUMO

Pistacia lentiscus L. (P. lentiscus) is an evergreen shrub (Anacardiaceae family) primarily found in the Mediterranean region. The plant has been thoroughly characterized, resulting in a high concentration of bioactive compounds as flavonoids and phenolics. Moreover, P. lentiscus was revealed to possess a great nutritional and industrial importance because of its variety of biological activities, including antibacterial, anti-inflammatory, anti-atherogenic and antioxidant properties. Many of its beneficial health properties and applications date back to antiquity, and the European Medicines Agency officially acknowledged it as an herbal medicinal product. Indeed, it is widely employed in conventional medicine to treat several diseases, including type 2 diabetes (T2D). On this basis, this review aims to summarize and describe the chemical composition of different parts of the plant and highlight the potential of P. lentiscus, focusing on its antidiabetic activities. The plant kingdom is drawing increasing attention because of its complexity of natural molecules in the research of novel bioactive compounds for drug development. In this context, P. lentiscus demonstrated several in vitro and in vivo antidiabetic effects, acting upon many therapeutic T2D targets. Therefore, the information available in this review highlighted the multitarget effects of P. lentiscus and its great potential in T2D treatment.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Pistacia , Extratos Vegetais , Pistacia/química , Hipoglicemiantes/farmacologia , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Fitoterapia , Animais
20.
Chem Biol Interact ; 397: 111087, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823536

RESUMO

Xanthine oxidase (XO) plays a critical role in purine catabolism, catalyzing the conversion of hypoxanthine to xanthine and xanthine to uric acid, contributing to superoxide anion production. This process is implicated in various human diseases, particularly gout. Traditional XO inhibitors, such as allopurinol and febuxostat, while effective, may present side effects. Our study focuses on Asphodelus microcarpus, a plant renowned for traditional anti-inflammatory uses. Recent investigations into its phenolic-rich flowers, notably abundant in luteolin derivatives, reveal its potential as a natural source of XO inhibitors. In the present research, XO inhibition by an ethanolic flowers extract from A. microcarpus is reported. In silico docking studies have highlighted luteolin derivatives as potential XO inhibitors, and molecular dynamics support that luteolin 7-O-glucoside has the highest binding stability compared to other compounds and controls. In vitro studies confirm that luteolin 7-O-glucoside inhibits XO more effectively than the standard inhibitor allopurinol, with an IC50 value of 4.8 µg/mL compared to 11.5 µg/mL, respectively. These findings underscore the potential therapeutic significance of A. microcarpus in managing conditions related to XO activity. The research contributes valuable insights into the health-promoting properties of A. microcarpus and its potential application in natural medicine, presenting a promising avenue for further exploration in disease management.


Assuntos
Inibidores Enzimáticos , Luteolina , Simulação de Acoplamento Molecular , Xantina Oxidase , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Luteolina/química , Luteolina/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Simulação de Dinâmica Molecular , Flores/química , Alopurinol/farmacologia , Alopurinol/química , Humanos , Sítios de Ligação
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