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1.
Molecules ; 28(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37630288

RESUMO

Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies were applied to characterize and compare the chemical shifts in the polyphenols' regions of some fruit wines. The obtained results showed that FTIR spectra (1800-900 cm-1) and 1H NMR (δ 6.5-9.3 ppm) of different fruit wines can be used as main indices of the year of vintage and quality of fruit wines. In addition to the classical determination of antioxidant profiles and bioactive substances in wines, fluorometric measurements were used to determine the interactions of wine substances with the main human serum proteins. The results showed relatively high binding properties of wines with the highest one for pomegranate, followed by kiwifruit and persimmon wines. The interactions of vitamin C, catechin and gallic acid with human serum albumin (HSA) were also examined by docking studies. The docking calculations showed that gallic acid has a stronger binding affinity compared to catechin and vitamin C. The stronger binding affinity of gallic acid may be due to three hydrogen bonds and pi-pi interactions. The fluorescence and docking studies proved that only the bioactive compounds of wines and not the amount of alcohol have high binding properties to human serum proteins. The emphasis in this report was made on the utility of FTIR, NMR and fluorescence of wines as a mean of wine authentication and its fingerprint. The findings, based on polyphenols from fruits and fruit wines, their bioactivity and health properties, offer valuable insights for future endeavours focused on designing healthy food products.


Assuntos
Catequina , Vinho , Humanos , Frutas , Análise de Fourier , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Ascórbico , Vitaminas , Espectroscopia de Ressonância Magnética
2.
J Chem Phys ; 157(24): 244301, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36586970

RESUMO

The ability to design catalysis largely depends on our understanding of the electrostatic effect of the surrounding on the bonds participating in the reaction. Here, we used a simplistic model of point charges (PCs) to determine a set of rules guiding how to construct PC-bond arrangement that can strengthen or weaken different chemical bonds. Using valence bond theory to calculate the in situ bond energies, we show that the effect of the PC mainly depends on the bond's dipole moment irrespective of its type (being covalent or charge shift). That is, polar bonds are getting stronger or weaker depending on the sign and location of the PC, whereas non- or weakly polar bonds become stronger or weaker depending only on the location of the PC and to a smaller extent compared with polar bonds. We also show that for polar bonds, the maximal bond strengthening and weakening effect can be achieved when the PC is placed along the bond axis, as close as possible to the more and less polarizable atom/fragment, respectively. Finally, due to the stabilizing effects of polarizability, we show that, overall, it is easier to cause bond strengthening compared with bond weakening. Particularly, for polar bonds, bond strengthening is larger than bond weakening obtained by an oppositely signed PC. These rules should be useful in the future design of catalysis in, e.g., enzyme active sites.


Assuntos
Catálise , Eletricidade Estática
3.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361562

RESUMO

Fruit used in the common human diet in general, and kiwifruit and persimmon particularly, displays health properties in the prevention of heart disease. This study describes a combination of bioactivity, multivariate data analyses and fluorescence measurements for the differentiating of kiwifruit and persimmon, their quenching and antioxidant properties. The metabolic differences are shown, as well in the results of bioactivities and antioxidant capacities determined by ABTS, FRAP, CUPRAC and DPPH assays. To complement the bioactivity of these fruits, the quenching properties between extracted polyphenols and human serum proteins were determined by 3D-fluorescence spectroscopy studies. These properties of the extracted polyphenols in interaction with the main serum proteins in the human metabolism (human serum albumin (HSA), α-ß-globulin (α-ß G) and fibrinogen (Fgn)), showed that kiwifruit was more reactive than persimmon. There was a direct correlation between the quenching properties of the polyphenols of the investigated fruits with serum human proteins, their relative quantification and bioactivity. The results of metabolites and fluorescence quenching show that these fruits possess multiple properties that have a great potential to be used in industry with emphasis on the formulation of functional foods and in the pharmaceutical industry. Based on the quenching properties of human serum proteins with polyphenols and recent reports in vivo on human studies, we hypothesize that HSA, α-ß G and Fgn will be predictors of coronary artery disease (CAD).


Assuntos
Actinidia/química , Antioxidantes/química , Diospyros/química , Frutas/química , Extratos Vegetais/química , Polifenóis/química , Antioxidantes/farmacologia , Humanos , Polifenóis/farmacologia
4.
Biomacromolecules ; 20(8): 2934-2941, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31259534

RESUMO

We report here on the synthesis, characterization, degradation, and drug release of acetal-protected gluconic acid-based poly(α-hydroxy ester). This polyester was synthesized by ring-opening polymerization of O-carboxyanhydride of acetal-protected gluconic acid. The polymer undergoes hydrolytic degradation under mild acidic media, whereas minimal degradation takes place under physiological pH. Under acidic conditions, the acetal-protecting groups are hydrolyzed, resulting in a water-soluble polyester with saccharide side chains that erodes from the surface, leaving the bulk of the polymer matrix intact. At pH 3.5, zero-order kinetics was maintained for 50 days accounting for ∼75% drug release. These biodegradable, pH-responsive, sustained zero-order release kinetics of the polymer have application as drug carriers for oral drug delivery or medical implants or also for nonmedical applications.


Assuntos
Proliferação de Células , Dexametasona/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Gluconatos/química , Hidrogéis/química , Polímeros/química , Animais , Dexametasona/farmacologia , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Camundongos , Células NIH 3T3 , Polietilenoglicóis
5.
Chemistry ; 21(7): 3108-14, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25529335

RESUMO

The design of Pt(IV) pro-drugs as anticancer agents is predicated on the assumption that they will not undergo substitution reactions before entering the cancer cell. Attempts to improve the cytotoxic properties of Pt(IV) pro-drugs included the use of haloacetato axial ligands. Herein, we demonstrate that Pt(IV) complexes with trifluoroacetato (TFA) or dichloroacetato (DCA) ligands can be unstable under biologically relevant conditions and readily undergo hydrolysis, which results in the loss of the axial TFA or DCA ligands. The half-lives for Pt(IV) complexes with two TFA or DCA ligands at pH 7 and 37 °C range from 6 to 800 min, which is short relative to the duration of cytotoxicity experiments that last 24-96 h. However, complexes with two monochloroacetato (MCA) or acetato axial ligands are stable under biologically relevant conditions. The loss of the axial ligands depends primarily on the electron-withdrawing strength of the axial ligands, but also upon the nature of the equatorial ligands. We were unable to find obvious correlations between the structures of the Pt(IV) complexes and the rates of decay of the parent compounds. The X-ray crystal structures of the bis-DCA and bis-MCA Pt(IV) derivatives of oxaliplatin did not reveal any significant structural differences that could explain the observed differences in stability.


Assuntos
Platina/química , Pró-Fármacos/química , Humanos , Hidrólise , Ligantes , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo
6.
J Med Chem ; 66(8): 5536-5549, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37057997

RESUMO

There is growing interest in non-psychoactive phytocannabinoids, namely cannabidiol (CBD), cannabigerol (CBG), and cannabichromene, as potential leads for novel therapeutic agents. In this study, we report on the development of new derivatives in which we methylated either position 4 of olivetol or the phenolic positions of olivetol, or both. We introduce a refinement on previously reported chemical procedures for phytocannabinoid derivatization as well as the biological evaluation of all derivatives in anti-inflammatory in vivo models. Compounds such as the CBD derivative, 2 and the CBG derivative, 11, significantly reduced cytokine levels when compared to their parent compounds. Moreover, both of these derivatives proved to be as potent as dexamethasone for the inhibition of IL-1ß. We believe that these new derivatives, as described herein, can be further developed as novel drug candidates for inflammatory conditions.


Assuntos
Canabidiol , Canabidiol/farmacologia , Resorcinóis , Anti-Inflamatórios , Citocinas
7.
Bioconjug Chem ; 21(8): 1425-31, 2010 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-20715847

RESUMO

The ability to cleave DNA with the aid of chemical nucleases has been a challenge in the scientific community, particularly in the absence of a redox active metal ion. Inspired by structural characterization of the active site found in Staphylococcal nuclease, we have designed a series of organic molecule comprising cyclic pentapeptides conjugated to a DNA intercalator (e.g., anthraquinone). The cyclic peptide is designed to cleave the phosphodiester backbone, whereas the intercalator is expected to improve binding affinity to the substrate (DNA). Our lead compound (1-AQ), composed of the cyclic peptide cyc-d-Lys-Gly-Arg-Ser-Arg conjugated to anthraquinone, degrades DNA into small fragments at physiologically relevant conditions (i.e., 37 degrees C, pH = 7.4). We find that 1-AQ is highly effective in degrading duplex DNA at micromolar concentrations as corroborated by agarose and polyacrylamide gel electrophoresis. Changing the DNA intercalator to acridine (1-Ac) renders the compound comparable in nuclease activity to 1-AQ. In comparison to control compounds (Lin-1 and 1) that lack either the cyclic scaffold or the DNA intercalator, our lead compound (1-AQ) is found to be significantly more active as a DNA chemical nuclease. We have studied the importance of the triad (Arg-Ser-Arg) as the designed module for DNA cleavage. Changing l-Ser to l-Glu (cyc-d-Lys-Gly-Arg-Glu-Arg, Glu-AQ) results in an inactive compound, whereas the cyclic peptide Gly-AQ (cyc-d-Lys-Gly-Arg-Gly-Arg, where glycine replaces l-serine) has similar DNA nuclease activity to 1-AQ. In addition, changing the stereochemistry from d-lysine to l-lysine results in a cyclic peptide (1-L-AQ) exerting weak DNA nuclease activity, highlighting the importance of the cyclic backbone conformation for efficient DNA nuclease activity. The addition of ROS scavengers does not reduce DNA nuclease activity; an observation that supports a hydrolytic cleavage mechanism. Finally, we have estimated the kinetics of DNA cleavage of a 15-mer duplex DNA substrate by compound 1-AQ. By monitoring DNA duplex degradation by following the change in absorbance (hyperchromicity) at various 1-AQ concentrations, we report a maximal k(obs) value (as an underestimation of k(max)) of 1.62 h(-1) at a 7.5-fold of 1-AQ. We have also compared the other two active peptide conjugates, namely, 1-Ac and Gly-AQ to that of 1-AQ. Both compounds exert similar nuclease activity to that of 1-AQ. To the best of our knowledge, this is the most active metal-free DNA nuclease reported to date that exerts its DNA nuclease activity at biologically relevant conditions.


Assuntos
DNA/química , Desoxirribonucleases/química , Peptídeos Cíclicos/química , Antraquinonas/química , DNA/síntese química , DNA/efeitos dos fármacos , Clivagem do DNA/efeitos dos fármacos , Desoxirribonucleases/metabolismo , Estrutura Molecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/farmacologia , Estereoisomerismo
8.
Bioconjug Chem ; 21(4): 616-21, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20345124

RESUMO

DNA photocleavage by triplex forming oligonucleotides (TFO) has potential implications in both biotechnology and medicine. We have synthesized a series of homopurine DNA and DNA/LNA 14-mers to which an amino acid (glycine or l-tryptophan) and a cyanine dye are covalently linked. Two cyanine dyes were examined that include a quinolinium ring linked to a benzothiazolium ring through a monomethine (TO1) or trimethine (TO2) linker. The 14-mer sequence was chosen to target mdm2, a ubiquitin ligase (E3) that regulates p53 by promoting its ubiquitylation and proteosomal degradation. Such inhibition has been previously proposed as a therapeutic approach to target wild-type p53-expressing cancers. To examine whether our TFO conjugates photocleave the mdm2 target, we incubated the various conjugates with the mdm2 plasmid and irradiated the samples with visible light. We show that only the TFO with the complementary sequence and with an intervening l-tryptophan leads to the linearization of the plasmid after a short irradiation time (10 min) exciting the dye (lambda(max)(TO1) = 500 nm and lambda(max)(TO2) = 630 nm) with visible light. Furthermore, the photoreactivity is more pronounced for the LNA/DNA conjugate, an observation that is consistent with improved hybridization to the DNA target. Sequence specificity of the photoreaction is further corroborated on a synthetic 44-mer duplex containing the TFO site. Evidence for a ROS-dependent mechanism is also given and discussed.


Assuntos
Aminoácidos/química , Carbocianinas/química , Clivagem do DNA , DNA/química , Luz , Oligonucleotídeos/química , Oxigênio/química , Fotoquímica , Plasmídeos/química
9.
ChemMedChem ; 12(7): 510-519, 2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28206707

RESUMO

The discrepancy between the in vitro cytotoxic results and the in vivo performance of Pt56MeSS prompted us to look into its interactions and those of its PtIV derivatives with human serum (HS), human serum albumin (HSA), lipoproteins, and serum-supplemented cell culture media. The PtII complex, Pt56MeSS, binds noncovalently and reversibly to slow-tumbling proteins in HS and in cell culture media and interacts through the phenanthroline group with HSA, with a Kd value of ∼1.5×10-6 m. All PtIV complexes were found to be stable toward reduction in HS, but those with axial carboxylate ligands, cct-[Pt(1S,2S-DACH)(5,6-dimethyl-1,10-phenantroline)(acetato)2 ](TFA)2 (Pt56MeSS(OAc)2 ) and cct-[Pt(1S,2S-DACH)(5,6-dimehtyl-1,10-phenantroline)(phenylbutyrato)2 ](TFA)2 (Pt56MeSS(PhB)2 ), were spontaneously reduced at pH 7 or higher in phosphate buffer, but not in Tris buffer (pH 8). HS also decreased the rate of reduction by ascorbate of the PtIV complexes relative to the reduction rates in phosphate buffer, suggesting that for this compound class, phosphate buffer is not a good model for HS.


Assuntos
Complexos de Coordenação/química , Platina/química , Ácido Ascórbico/química , Complexos de Coordenação/sangue , Complexos de Coordenação/síntese química , Cicloexilaminas/química , Estabilidade de Medicamentos , Técnicas Eletroquímicas , Humanos , Espectroscopia de Ressonância Magnética , Oxirredução , Fenantrolinas/química , Proibitinas
10.
J Control Release ; 105(1-2): 52-67, 2005 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-15955366

RESUMO

Injectable polymeric formulation for paclitaxel was studied. Poly ricinoleic acid and sebacic acid were synthesized. The effect of additives on the viscosity of polymer, paclitaxel release, and polymer degradation was investigated both in vitro and in vivo. Additives that were used in this study were ricinoleic acid, phospholipid, PEG 400, and PEG 2000. Addition of 20% ricinoleic acid to P(SA:RA)3:7 liquefied the formulation and allowed injection of the formulation containing paclitaxel via a 22-G needle at room temperature with no effect on paclitaxel release rate. Addition of PEG 400, PEG 2000, and phospholipid to the formulation did not affect the paclitaxel release from the formulation. The degradation of modified formulations with paclitaxel and additives was examined in vitro and by subcutaneous injection of liquid formulations to the backspace via a 22-G needle into seven groups of four C3H mice. In vivo formulations with additives (20% ricinoleic acid and PEG or phospholipid) and 5% paclitaxel content degraded faster than the formulation with only 20% ricinoleic acid and the same paclitaxel content: 51% and 54% versus 43%. The slowest degradation (26% in 1 week) was of the formulation containing 10% paclitaxel. The release rate in vivo was affected by the paclitaxel content; the higher the content, the slower was the release. By using additives, we could adjust the physical characteristics of the surgical paste while maintaining a desirable system for sustained paclitaxel release.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Ácidos Decanoicos/química , Portadores de Fármacos/química , Paclitaxel/administração & dosagem , Polímeros/química , Ácidos Ricinoleicos/química , Animais , Antineoplásicos Fitogênicos/química , Química Farmacêutica , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Feminino , Hidrólise , Camundongos , Camundongos Endogâmicos C3H , Paclitaxel/química , Veículos Farmacêuticos , Fosfolipídeos , Polietilenoglicóis , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Viscosidade
11.
J Med Chem ; 56(5): 1811-29, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23384387

RESUMO

Newly synthesized acylethanolamide derivatives oleoyl-L-valinolamide (1), oleoyl-D-valinolamide (2), elaidoyl-L-valinolamide (3), elaidoyl-D-valinolamide (4) stearoyl-L-valinolamide (5), and palmitoyl-L-valinolamide (6) were investigated in mice as antiobesity compounds. Compounds 1, 2, 5, 6 significantly decreased body weight by 6.57% following eight injections of 1 mg/kg i.p. during 39 days, while 3 and 4 showed no such activity. Receptor binding indicated that no compound activated CB1, CB2, PPARα, or TRPV1 receptors. Hypothalamic RT-PCR showed that mRNA expression of the anorexigenic genes POMC and CART was up-regulated by 1, 2, 5 and 1, 2, respectively, while that of the orexigenic genes NPY and CaMKK2 was down-regulated by the respective compounds 1, 5, 6 and 1, 2, 5. Oleoyl-L-valinolamide enhances anorectic pathways and lead to decreased glucose levels, enhanced locomotor activity, and improved cognition. Effects of oleoyl-L-valinolamide on weight were dose-dependent, and it could be given orally. 1, 2, 4, 5 down-regulated FAAH mRNA expression.


Assuntos
Amidas/farmacologia , Fármacos Antiobesidade/síntese química , Peso Corporal/efeitos dos fármacos , Hipotálamo/metabolismo , Neuropeptídeo Y/antagonistas & inibidores , Ácidos Oleicos/síntese química , Pró-Opiomelanocortina/biossíntese , Valina/análogos & derivados , Animais , Fármacos Antiobesidade/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Etanolaminas/farmacologia , Feminino , Hipotálamo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Neuropeptídeo Y/biossíntese , Ressonância Magnética Nuclear Biomolecular , Ácidos Oleicos/farmacologia , Valina/síntese química , Valina/farmacologia
12.
J Control Release ; 160(2): 401-6, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22227025

RESUMO

OBJECTIVE: Preparation and characterization of an oral pro-dispersion liposphere formulation for cyclosporin, a water insoluble drug with limited bioavailability. METHODS: Pro-dispersion formulation consisted of a solid fat, dispersing agents and amphiphilic solvents as the major components besides cyclosporin A (CsA) were prepared in the present work. For preparation of this formulation, phospholipid was dissolved in pharmaceutically acceptable water soluble organic solvent, thereafter CsA along with other components was added and formulation optimization was carried out. After formulation preparation, particle size determination and in vitro release study was carried out. Additionally, ultracentrifugation, TEM, Cryo-TEM and DSC techniques were used for in vitro characterization of formulation. The prepared system was also compared with marketed Neoral® microemulsion formulation. RESULTS: Liposphere formulations were prepared and optimized as according to procedure. Though, determination of in vitro characteristics of such formulations is complex and difficult, yet selected and performed tests confirmed formation and existence of solid liposphere particles upon dispersion of formulation in water. It was also observed that particle size is influenced by the type of solid fat used and amphiphilic solvent present in the formulation. Prepared pro-dispersion was found to be stable for 2 years under normal storage conditions. CONCLUSION: Prepared pro-dispersion liposphere formulation is a homogeneous solution of a lipophilic drug such as cyclosporin in a mixture of surfactants, lipids and ethyl lactate proved to spontaneously form dispersion when added to aqueous media. This formulation concept has a potential clinical use for improved bioavailability of water insoluble drugs.


Assuntos
Ciclosporina/administração & dosagem , Portadores de Fármacos/química , Imunossupressores/administração & dosagem , Triglicerídeos/química , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Microscopia Crioeletrônica , Composição de Medicamentos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
13.
J Agric Food Chem ; 60(28): 6984-93, 2012 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-22712722

RESUMO

Comparison between organic and conventional kiwifruit cultivars 'Hayward' and 'Bidan', which was done by four radical scavenging assays, ESI-MS, and DSC measurements, showed significant differences between the cultivars. Such results were not estimated in kiwifruit growing under organic and conventional conditions. The extraction of bioactive compounds was done by two different methods: sequential extraction with ethyl acetate followed by methanol and maceration with methanol and ethyl acetate. The highest yield of polyphenols was found in the new cultivar 'Bidan' in comparison with the classic 'Hayward', by direct extraction with methanol. This is the first investigation of 'Bidan' kiwifruit cultivar, grown under organic conditions and compared with 'Hayward' organic. High contents of bioactive compounds and antioxidant and antiproliferative properties of the two kiwifruit cultivars justify their use as sources of valuable antioxidants. It is necessary to continue this study as a long-term experiment to eliminate the influence of seasonality.


Assuntos
Actinidia , Antioxidantes/análise , Alimentos Orgânicos , Frutas/química , Promoção da Saúde , Antineoplásicos Fitogênicos , Antioxidantes/farmacologia , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Flavonoides/análise , Humanos , Extratos Vegetais/farmacologia , Polifenóis/análise , Taninos/análise
14.
Pharm Res ; 23(6): 1306-12, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16741657

RESUMO

A systematic study on the degradation and drug release from L-lactic acid and ricinoleic-acid-based copolyesters is reported. These copolyesters were synthesized by ring opening polymerization (ROP), melt condensation (COND) and transesterification (TRANS) of high molecular weight poly(lactic acid) (PLA) with ricinoleic acid (PLA-RA), and repolymerization by condensation to yield random and block copolymers of weight average molecular weights (Mw) between 3000 and 13,000. All polymers showed an almost zero-order weight loss, with a 20-40% loss after 60 days of incubation. Lactic acid release to the degradation solution is proportional to weight loss of the polymer samples. The main decrease in molecular weight was observed during the first 20 days, followed by a slow degradation phase, which kept the number average molecular weight (Mn) at 4000-2000 for another 40 days. Water-soluble 5FU was released from ricinoleic-acid-based polymers faster than slightly water-soluble triamcinolone. Drug release into phosphate-buffered saline (pH 7.4, 0.1 M) at 37 degrees C from P(LA-RA) 60:40 prepared by condensation of the acids was faster than from pasty P(PLA-RA) 60:40 synthesized by transesterification for both drugs.


Assuntos
Antimetabólitos Antineoplásicos/química , Portadores de Fármacos/síntese química , Glucocorticoides/química , Ácido Láctico/síntese química , Poliésteres/síntese química , Ácidos Ricinoleicos/síntese química , Fluoruracila/química , Hidrólise , Cinética , Peso Molecular , Solubilidade , Temperatura de Transição , Triancinolona/química
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