RESUMO
Transcriptional enhanced associate domain (TEAD) proteins bind to YAP/TAZ and mediate YAP/TAZ-induced gene expression. TEADs are not only the key transcription factors and final effector of the Hippo signaling pathway, but also the proteins that regulate cell proliferation and apoptosis. Disorders of Hippo signaling pathway occur in liver cancer, breast cancer, colon cancer and other cancers. S-palmitylation can stabilize the structure of TEADs and is also a necessary condition for the binding of TEADs to YAP/TAZ. The absence of TEAD palmitoylation prevents TEADs from binding to chromatin, thereby inhibiting the transcription and expression of downstream target genes in the Hippo pathway through a dominant-negative mechanism. Therefore, disrupting the S-palmitylation of TEADs has become an attractive and very feasible method in cancer treatment. The palmitate binding pockets of TEADs are conservative, and the crystal structures of TEAD2-palmitoylation inhibitor complexes and the potential TEAD2 inhibitors are more than other TEADs, TEAD2 can be selected to be the target receptor. In this study, structure-based and ligand-based virtual screening, molecular dynamics simulations, Molecular Mechanics Poisson-Boltzmann Surface Area (MM/PBSA) calculations, residue decomposition binding energy calculations, and ADME predictions have been performed to discover 11 potential TEAD2 S-palmitylation inhibitors. ChEBML196567 and ZINC000013942794 are the most recommended, because they formed strong binding energies and stable hydrogen bonds with TEAD2 and have good drugbility and high human oral absorption. We found that it was easier to find the targeting small molecules using a combination of structure-based and ligand-based virtual screening methods. Besides, a new core structure has been found in the selected small molecules. In addition, we analyzed the binding modes of these small molecules to TEAD2, and confirmed the hot spot residues Cys380, Ser345, Tyr426, Phe428, Ile408, and Met379. AVAILABILITY OF DATA AND MATERIAL: Supplementary materials are available online.
Assuntos
Neoplasias da Mama , Palmitatos , Fatores de Transcrição de Domínio TEA , Feminino , Humanos , Ligantes , Simulação de Dinâmica Molecular , Palmitatos/química , Palmitatos/metabolismo , Fatores de Transcrição de Domínio TEA/química , Fatores de Transcrição de Domínio TEA/metabolismo , Proteínas de Sinalização YAP/genética , Proteínas de Sinalização YAP/metabolismoRESUMO
A rational-based process was adopted for repurposing pyrrolidine-based 3-deoxysphingosylphosphorylcholine analogs bearing variable acyl chains, different stereochemical configuration and/or positional relationships. Structural features were highly influential on activity. Amongst, enantiomer 1e having 1,2-vicinal relationship for the -CH2O- and the N-acyl moieties, a saturated palmitoyl chain and an opposite stereochemical configuration to natural sphingolipids was the most potent hit compound against promastigotes showing IC50 value of 28.32 µM. The corresponding enantiomer 1a was 2-fold less potent showing a eudismic ratio of 0.54 in promastigotes. Compounds 1a and 1e inhibited the growth of amastigotes more potently relative to promastigotes. Amongst, enantiomer 1a as the more selective and safer. In silico docking study using a homology model of Leishmania donovani inositol phosphoceramide synthase (IPCS) provided plausible reasoning for the molecular factors underlying the found activity. Collectively, this study suggests compounds 1a and 1e as potential hit compounds for further development of new antileishmanial agents.
Assuntos
Antiprotozoários/química , Leishmania donovani/efeitos dos fármacos , Fosforilcolina/química , Pirrolidinas/química , Amida Sintases/metabolismo , Antiprotozoários/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Palmitatos/química , Pirrolidinas/farmacologia , Esfingomielinas/química , Relação Estrutura-AtividadeRESUMO
Bacterial biofilms are a major health concern, mainly due to their contribution to increased bacterial resistance to well-known antibiotics. The conventional treatment of biofilms represents a challenge, and frequently, eradication is not achieved with long-lasting administration of antibiotics. In this context, the present work proposes an innovative therapeutic approach that is focused on the encapsulation of N-acetyl-l-cysteine (NAC) into lipid nanoparticles (LNPs) functionalized with d-amino acids to target and disrupt bacterial biofilms. The optimized formulations presented a mean hydrodynamic diameter around 200 nm, a low polydispersity index, and a high loading capacity. These formulations were stable under storage conditions up to 6 months. In vitro biocompatibility studies showed a low cytotoxicity effect in fibroblasts and a low hemolytic activity in human red blood cells. Nevertheless, unloaded LNPs showed a higher hemolytic potential than NAC-loaded LNPs, which suggests a safer profile of the latter. The in vitro antibiofilm efficacy of the developed formulations was tested against Staphylococcus epidermidis (Gram-positive) and Pseudomonas aeruginosa (Gram-negative) mature biofilms. The results showed that the NAC-loaded LNPs were ineffective against S. epidermidis biofilms, while a significant reduction of biofilm biomass and bacterial viability in P. aeruginosa biofilms were observed. In a more complex therapeutic approach, the LNPs were further combined with moxifloxacin, revealing a beneficial effect between the LNPs and the antibiotic against P. aeruginosa biofilms. Both alone and in combination with moxifloxacin, unloaded and NAC-loaded LNPs functionalized with d-amino acids showed a great potential to reduce bacterial viability, with no significant differences in the presence or absence of NAC. However, the presence of NAC in NAC-loaded functionalized LNPs shows a safer profile than the unloaded LNPs, which is beneficial for an in vivo application. Overall, the developed formulations present a potential therapeutic approach against P. aeruginosa biofilms, alone or in combination with antibiotics.
Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Lipossomos/química , Nanopartículas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Acetilcisteína/química , Acetilcisteína/toxicidade , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Linhagem Celular , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Sinergismo Farmacológico , Humanos , Lipossomos/toxicidade , Camundongos , Testes de Sensibilidade Microbiana , Moxifloxacina/farmacologia , Nanopartículas/toxicidade , Palmitatos/química , Palmitatos/toxicidade , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/toxicidade , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Pseudomonas aeruginosa/fisiologiaRESUMO
Antibacterial drug resistance is considered one of the biggest threats to human health worldwide, and the overuse of antibiotics accelerates this problem. Multidrug-resistant (MDR) bacteria are becoming harder to treat as the antibiotics used to treat them become less effective. Therefore, it is necessary to evaluate novel methods to control MDR bacteria. In this study, 40 bacterial isolates were collected from diabetic patients. The sensitivity of 40 bacterial isolates to seven antibiotics was evaluated. Four bacterial isolates were resistant to all antibiotic groups. The MDR pathogenic bacteria were selected and identified morphologically and biochemically and confirmed by VITEK® 2 system as follows: Staphylococcus aureus W35, Pseudomonas aeruginosa D31, Klebsiella pneumoniae DF30, and K. pneumoniae B40. Identification of the most resistant P. aeruginosa D31 was confirmed by the sequencing of a 16S ribosomal RNA gene with an accession number (MW241596). The inhibitory activity of eight types of native grown plant extracts against MDR bacteria was studied. Clove alcoholic extract (CAE) showed the highest inhibitory activity against MDR bacteria. Gas chromatography-mass spectrometry analysis of partially purified CAE at 0.9 Rf detected by thin-layer chromatography showed an active compound named hexadecenoic acid methyl ester with the highest antimicrobial effect against clinical pathogenic bacteria. The formation of silver nanoparticles (AgNPs) by CAE was studied. Evaluation of AgNPs was investigated by X-ray diffraction, UV-Vis, and transmission electron microscopy. The antibacterial effect of AgNPs after 2, 4, and 6 days in light and dark conditions was evaluated. Finally, the AgNPs synthesized using CAE possess good inhibition activity against the tested pathogenic bacteria. As a result, the bactericidal components listed above were promising in reducing MDR bacteria and can be used for treatments of bacterial infection and in the development of safe products with a natural base.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Nanopartículas Metálicas/química , Palmitatos/química , Prata/química , Antibacterianos/química , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Diabetes Mellitus/microbiologia , Química Verde , Humanos , Testes de Sensibilidade Microbiana , Palmitatos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , RNA Ribossômico 16S/genética , Prata/farmacologia , Syzygium/químicaRESUMO
This work describes a novel approach for the synthesis of (-)-epigallocatechin gallate (EGCG) palmitate by a chemical-synthesis method, where the elevated stability of the EGCG derivative is achieved. Various parameters affecting the acylation process, such as the base, solvent, as well as the molar ratio of palmitoyl chloride, have been studied to optimize the acylation procedure. The optimized reaction condition was set as follows: EGCG/palmitoyl chloride/sodium acetate was under a molar ratio of 1:2:2, with acetone as the solvent, and the reaction temperature was 40 °C. Under the optimized condition, the yield reached 90.6%. The EGCG palmitate (PEGCG) was isolated and identified as 4'-O-palmitoyl EGCG. Moreover, the stability of PEGCG under different conditions was proved significantly superior to EGCG. Finally, PEGCG showed better inhibition towards α-amylase and α-glucosidase, which was 4.5 and 52 times of EGCG, respectively. Molecular docking simulations confirmed the in vitro assay results. This study set a novel and practical synthetic approach for the derivatization of EGCG, and suggest that PEGCG may act as an antidiabetic agent.
Assuntos
Catequina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Palmitatos/farmacologia , Polifenóis/química , Chá/química , Bacillus licheniformis/enzimologia , Catequina/síntese química , Catequina/química , Catequina/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Ligantes , Simulação de Acoplamento Molecular , Palmitatos/síntese química , Palmitatos/química , Saccharomyces cerevisiae/enzimologia , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismoRESUMO
Current efforts on inflammatory bowel diseases (IBD) treatment are focused on strategies for localised drug delivery at the intestinal mucosa. Despite the potential of curcumin (CC) for IBD treatment, its low solubility and stability limit its application. Thus, the design of nanocarriers that focus CC delivery at the intestinal epithelium is an area of interest. This work proposes α-tocopherol nanoemulsions (NE) stabilised by ascorbyl-2,6-dipalmitate (ADP) as intestinal CC-carriers. The antioxidant capacity of α-tocopherol and ADP could have a synergistic effect on IBD-affected tissues, characterised by an oxidative environment. We obtained nanoemulsions (NE-ADP) with size below 200 nm, negative surface charge, stable in gastrointestinal media and no toxic in the Caco-2 cell model. Intracellular retention of NE-ADP in Caco-2 cells was observed by confocal microscopy. The extremely low Papp values obtained for CC and α-tocopherol indicated the lack of transport across the Caco-2 monolayer. Control nanoemulsion stabilised by lecithin (NE-L) was greatly transported across the Caco-2 cells monolayer, confirming the relevance of ADP on the cellular retention of NE-ADP. The therapeutic potential of NE-ADP was shown by the significant decrease of intracellular ROS levels. Altogether, these results indicate the potential of NE-ADP as a novel approach for the treatment of IBD.
Assuntos
Ácido Ascórbico/química , Curcumina/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Palmitatos/química , alfa-Tocoferol/administração & dosagem , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Transporte Biológico , Células CACO-2 , Curcumina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Emulsões , Humanos , Lecitinas/química , Nanopartículas , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Solubilidade , alfa-Tocoferol/farmacologiaRESUMO
This work investigates the feasibility of using coffee silverskin (CSS) as a reinforcing agent in biobased polyethylene (BioPE) composites, by adding it in bulk and thin film samples. The effect of two different treatments, alkali bleaching (CSS_A) and esterification with palmitoyl chloride (CSS_P), on mechanical, thermal, morphological and water absorption behavior of produced materials at different CSS loading (10, 20 and 30 wt %) was investigated. A reactive graft copolymerization of BioPE with maleic anhydride was considered in the case of alkali treated CSS. It was found that, when introduced in bulk samples, improvement in the elastic modulus and a reduction in strain at maximum stress were observed with the increase in CSS fraction for the untreated and treated CSS composites, while the low aspect ratio of the CSS particles and their poor adhesion with the polymeric matrix were responsible for reduced ductility in films, decreasing crystallinity values and reduction of elastic moduli. When CSS_A and CSS_P are introduced in the matrix, a substantial reduction in the water uptake is also obtained in films, mainly due to presence of maleated PE, that builds up some interactions to eliminate the amounts of OH groups and hydrophobized CSS, due to the weakened absorption capacity of the functionalized CSS.
Assuntos
Café/química , Anidridos Maleicos/química , Palmitatos/química , Módulo de Elasticidade , Esterificação , Estudos de Viabilidade , Teste de Materiais , Propriedades de SuperfícieRESUMO
Nanostructured lipid carriers (NLC) belong to youngest lipid-based nanocarrier class and they have gained increasing attention over the last ten years. NLCs are composed of a mixture of solid and liquid lipids, which solubilizes the active pharmaceutical ingredient, stabilized by a surfactant. The miscibility of the lipid excipients and structural changes (polymorphism) play an important role in the stability of the formulation and are not easily predicted in the early pharmaceutical development. Even when the excipients are macroscopically miscible, microscopic heterogeneities can result in phase separation during storage, which is only detected after several months of stability studies. In this sense, this work aimed to evaluate the miscibility and the presence of polymorphism in lipid mixtures containing synthetic (cetyl palmitate, Capryol 90®, Dhaykol 6040 LW®, Precirol ATO5® and myristyl myristate) and natural (beeswax, cocoa and shea butters, copaiba, sweet almond, sesame and coconut oils) excipients using Raman mapping and multivariate curve resolution - alternating least squares (MCR-ALS) method. The results were correlated to the macroscopic stability of the formulations. Chemical maps constructed for each excipient allowed the direct comparison among formulations, using standard deviation of the histograms and the Distributional Homogeneity Index (DHI). Lipid mixtures of cetyl palmitate/Capryol®; cetyl palmitate/Dhaykol®; myristyl myristate/Dhaykol® and myristyl myristate/coconut oil presented a single histogram distribution and were stable. The sample with Precirol®/Capryol® was not stable, although the histogram distribution was narrower than the samples with cetyl palmitate, indicating that miscibility was not the factor responsible for the instability. Structural changes before and after melting were identified for cocoa butter and shea butter, but not in the beeswax. Beeswax + copaiba oil sample was very homogenous, without polymorphism and stable over 6â¯months. Shea butter was also homogeneous and, in spite of the polymorphism, was stable. Formulations with cocoa butter presented a wider histogram distribution and were unstable. This paper showed that, besides the miscibility evaluation, Raman imaging could also identify the polymorphism of the lipids, two major issues in lipid-based formulation development that could help guide the developer understand the stability of the NLC formulations.
Assuntos
Portadores de Fármacos/química , Lipídeos/química , Nanopartículas/química , Diglicerídeos/química , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes/química , Análise Multivariada , Miristatos/química , Palmitatos/química , Tamanho da Partícula , Óleos de Plantas/química , Polímeros/química , Propilenoglicóis/química , Solubilidade , Análise Espectral Raman , Tensoativos/química , Ceras/químicaRESUMO
Water-in-oil (W/O) emulsions with a discontinuous aqueous phase dispersed in a continuous camellia oil phase were prepared by using tea polyphenol palmitate (Tp-palmitate) particle as effective stabilizers and their properties were characterized by droplet size, slip melting point (SMP), stability, microstructure and rheology. The d(4,3) and d(3,2) decreased from 7.96⯵m to 4.67⯵m and from 5.98⯵m to 3.07⯵m, respectively, and the SMP rose from 33.73⯰C to 38.60⯰C when the Tp-palmitate concentration increased from 1.0% to 2.5% (m/v). The storage stability, freeze/thaw stability and thermal stability significantly enhanced and the droplets aggregation progressively increased with the increasing of Tp-palmitate concentration. The liquid camellia oil was transformed into solid-like viscoelastic emulsion gels with a SMP of 38.6⯰C when using 2.5% Tp-palmitate as particle stabilizers. This study provides a promising method for production of edible gel-like W/O emulsions using polyphenol-lipid complexes to potentially replace solid fats.
Assuntos
Camellia/química , Emulsões/química , Palmitatos/química , Óleos de Plantas/química , Camellia/metabolismo , Congelamento , Géis/química , Microscopia de Fluorescência , Polifenóis/química , Reologia , Resistência ao Cisalhamento , Chá/metabolismo , Temperatura , Viscosidade , Água/químicaRESUMO
Alkyldiethanolamides (fatty acid diethanolamides) synthesis from Terminalia catappa L. kernel oil was optimized using lypozyme as a catalyst. The result showed that the optimal reaction conditions were 2 hours reaction time, with a ratio of oil mass (g) to diethanolamine (mmol) of 1:5, a ratio of oil mass to enzyme (g) of 1: 0.075, and a temperature of 40°C. The percentage of alkyldiethanolamides at optimum condition was 56-60%. The synthesis results were also analyzed by FTIR. FTIR spectra revealed specific absorption at several wave numbers (3434 cm-1, 1655 cm-1, 1280 cm-1), indicating that amide and alcohol bonds (C=O, C-N, and O-H) were formed. GC-MS was employed to identify the types of fatty acid diethanolamides that were successfully synthesized. The fatty acid diethanolamides formed were palmitoyldiethanolamide (Rt = 32.96 min) and oleyldiethanolamide (Rt = 35.57 min). The total nitrogen content of alkyldietanolamides was 0.26%, or 0.19 mmol of the amide group in 1 g of sample.
Assuntos
Etanolaminas/química , Ácidos Oleicos/síntese química , Palmitatos/síntese química , Óleos de Plantas/química , Sementes/química , Terminalia/química , Catálise , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas , Nitrogênio/análise , Ácidos Oleicos/química , Palmitatos/química , Temperatura , Fatores de TempoRESUMO
As hydrolysis of carotenoid esters is believed to be highly efficient in vivo, their insufficient hydrolysis in in vitro-digestion models, particularly, regarding zeaxanthin diesters, is a current issue. Therefore, in this study, several factors related to the enzymatic hydrolysis were investigated in an adapted version of the standardized INFOGEST in vitro-digestion model, using zeaxanthin dipalmitate (ZDP) as a substrate. The results showed that pancreatic lipase was able to hydrolyze ZDP, whereas carboxyl ester lipase (CEL) substantially contributed to ZDP cleavage. Replacement of commonly used porcine with bovine bile extracts and the substitution of coffee creamer for soybean oil at identical fat contents both significantly improved hydrolysis efficiency and bioaccessibility of total zeaxanthin to better mimic in vivo conditions. Thus, bile and lipids selection for in vitro digestion of carotenoid esters was crucial. The combined use of coffee creamer, pancreatin, CEL, and bovine bile led to the highest hydrolysis efficiency of 29.5%.
Assuntos
Digestão , Palmitatos/química , Palmitatos/metabolismo , Xantofilas/química , Xantofilas/metabolismo , Animais , Bovinos , Hidrólise , Lipase/metabolismo , Óleo de Soja/química , SuínosRESUMO
Ascorbic acid (AA) possesses multiple beneficial functions, such as regulating collagen biosynthesis and redox balance in the skin. AA derivatives have been developed to overcome this compound's high fragility and to assist with AA supplementation to the skin. However, how AA derivatives are transferred into cells and converted to AA in the skin remains unclear. In the present study, we showed that AA treatment failed to increase the cellular AA level in the presence of AA transporter inhibitors, indicating an AA transporter-dependent action. In contrast, torisodium ascorbyl 6-palmitate 2-phosphate (APPS) treatment significantly enhanced the cellular AA level in skin cells despite the presence of inhibitors. In ex vivo experiments, APPS treatment also increased the AA content in a human epidermis model. Interestingly, APPS was readily metabolized and converted to AA in keratinocyte lysates via an intrinsic mechanism. Furthermore, APPS markedly repressed the intracellular superoxide generation and promoted viability associated with an enhanced AA level in Sod1-deficient skin cells. These findings indicate that APPS effectively restores the AA level and normalizes the redox balance in skin cells in an AA transporter-independent manner. Topical treatment of APPS is a beneficial strategy for supplying AA and improving the physiology of damaged skin.
Assuntos
Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/administração & dosagem , Fibroblastos/efeitos dos fármacos , Palmitatos/administração & dosagem , Administração Tópica , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Linhagem Celular , Epiderme/efeitos dos fármacos , Deleção de Genes , Humanos , Modelos Biológicos , Estrutura Molecular , Estresse Oxidativo , Palmitatos/química , Palmitatos/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismoRESUMO
BACKGROUND: Crude camellia seed oil is rich in free fatty acids, which must be removed to produce an oil of acceptable quality. In the present study, we reduced the free fatty acid content of crude camellia seed oil by lipophilization of epicatechin with these free fatty acids in the presence of Candida antarctica lipase B (Novozym 435), and this may enhance the oxidative stability of the oil at the same time. RESULTS: The acid value of crude camellia seed oil reduced from 3.7 to 2.5 mgKOH g-1 after lipophilization. Gas chomatography-mass spectrometry analysis revealed that epicatechin oleate and epicatechin palmitate were synthesized in the lipophilized oil. The peroxide, p-anisidine, and total oxidation values during heating of the lipophilized oil were much lower than that of the crude oil and commercially available camellia seed oil, suggesting that lipophilized epicatechin derivatives could help enhance the oxidative stability of edible oil. CONCLUSION: The enzymatic process to lipophilize epicatechin with the free fatty acids in crude camellia seed oil described in the present study could decrease the acid value to meet the quality standards for commercial camellia seed oil and, at the same time, obtain a new edible camellia seed oil product with good oxidative stability. © 2016 Society of Chemical Industry.
Assuntos
Antioxidantes/metabolismo , Camellia sinensis/química , Catequina/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Óleos de Plantas/química , Sementes/química , Antioxidantes/análise , Antioxidantes/química , Catequina/análogos & derivados , Catequina/análise , Catequina/química , China , Gorduras Insaturadas na Dieta/análise , Gorduras Insaturadas na Dieta/metabolismo , Enzimas Imobilizadas/metabolismo , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/química , Manipulação de Alimentos , Qualidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta/efeitos adversos , Interações Hidrofóbicas e Hidrofílicas , Ácidos Oleicos/análise , Ácidos Oleicos/química , Ácidos Oleicos/metabolismo , Oxirredução , Palmitatos/análise , Palmitatos/química , Palmitatos/metabolismo , SolubilidadeRESUMO
In this study, decomposition products of glycidyl palmitate (GP) of fatty acids heated at high temperature such as deep frying were investigated. When GP and tripalmitin (TP) were heated at 180 and 200 °C, they were decreased with heating time. The weight of GP was less than that of TP, although both GP and TP were converted to polar compounds after heating. The decomposition rate of GP was higher than TP. Both GP and TP produced considerable amounts of hydrocarbons and aldehydes during heating. Aldehydes produced from GP and TP included saturated aldehydes with carbon chain length of 3-10, while hydrocarbons consisted of carbon chain length of 8-15. It was observed that major hydrocarbons produced from GP during heating were pentadecane. Moreover, the level of carbon dioxide (CO2) released from GP was higher than that of TP. It was suggested that fatty acids in GE might be susceptible to decarboxylation. From these results, GP might be quickly decomposed to hydrocarbons, aldehydes and CO2 besides polar compounds by heating, in comparison with TP.
Assuntos
Compostos de Epóxi/química , Palmitatos/química , Triglicerídeos/química , Aldeídos/análise , Aldeídos/química , Alcanos/química , Cromatografia em Camada Fina , Culinária , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas , Calefação , Hidrocarbonetos/análise , Hidrocarbonetos/química , Óleos de Plantas/química , TemperaturaRESUMO
HYPOTHESIS: The phase behavior and the properties of water, oil, surfactant, and cosurfactant mixtures depend on the fine balance of different forces, among them the bending energy of the amphiphilic film. Thus, it should be possible to control the structural evolution of nonionic microemulsions by the cosurfactant content and the hydration of the surfactant headgroup. EXPERIMENTS: An extensive investigation of the pseudoternary phase diagram of mixtures of water, isopropyl palmitate, polyoxyethylene (10) oleyl ether Brij 97 (C18E10), and butanol is presented for two different cosurfactant concentrations, thereby varying the hydrophilicity of the amphiphile. The studies were performed employing conductometric titrations, differential scanning calorimetry (DSC), and small-angle neutron scattering (SANS). FINDINGS: A systematic growth of the domain sizes and correlation lengths is observed by increasing the water content in the initial oil/surfactant solution. The formation of a bicontinuous structure, as deduced from conductivity is directly related to the presence of free water unbound to the EO units of the surfactant, as determined by DSC. The experimental results, e.g., the extension of the different phase regions and the mesoscopic structure are discussed on a molecular level, therefore providing a direct link between the composition of the microemulsions and the resulting structure and properties.
Assuntos
1-Butanol/química , Emulsões/química , Palmitatos/química , Transição de Fase , Óleos de Plantas/química , Polietilenoglicóis/química , Varredura Diferencial de Calorimetria , Interações Hidrofóbicas e Hidrofílicas , Tensoativos/químicaRESUMO
Nanocarriers and electroporation (also named electropermeabilization) are convenient methods to increase drug transport. In the current study, we present an effective support of drug delivery into cancer cells, utilizing these methods. We compare the efficiency of each of them and their combination. Multifunctional solid lipid nanoparticles (SLNs) loaded with a cyanine-type IR-780 - acting as a diagnostic agent and a photosensitizer, and a flavonoid derivative - baicalein (BAI) or fisetin (FIS) as a therapeutic cargo - were fabricated via solvent-diffusion method. A therapy supplemented with flavonoids may provide a more precise method to apply desirable lower drug doses and is more likely to result in lower toxicity and a decrease in tumor growth. The SLNs were stabilized with Phospholipon 90G at various concentrations; cetyl palmitate (CP) was applied as a solid matrix. The obtained nanosystems were characterized by dynamic light scattering (size along with size distribution), UV-vis (cargos encapsulation efficiency) and atomic force microscopy (morphology and shape). The obtained SLNs were used as drug carriers alone and in combination with electropermeabilization induced by millisecond pulsed electric fields of high intensity. Two cell lines were selected for the study: LoVo and CHO-K1. The viability was assessed after electroporation alone, the use of electroporation and nanoparticles, and nanoparticles or drugs alone. The intracellular accumulation of cyanine IR-780 and the impact on intracellular structure organization of cytoskeleton was visualized with confocal microscopy method with alpha-actin and beta-tubulin. In this study, the efficacy of nanoparticles with mixed cargo, additionally enhanced by electroporation, is demonstrated to act as an anticancer modality to eliminate cancer cells.
Assuntos
Neoplasias do Colo/patologia , Portadores de Fármacos/química , Eletroporação , Flavonoides/química , Indóis/química , Nanopartículas/química , Palmitatos/química , Animais , Células CHO , Linhagem Celular Tumoral , Chlorocebus aethiops , Neoplasias do Colo/tratamento farmacológico , Cricetulus , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Citoesqueleto/efeitos da radiação , Flavanonas/química , Flavanonas/farmacologia , Flavanonas/uso terapêutico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Flavonóis , Humanos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Superóxido Dismutase/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
OBJECTIVE: The overall objective of this work is to determine the percutaneous absorption of chlorpromazine hydrochloride from pluronic lecithin organogels (PLO gels) and verify the suitability of topically applied chlorpromazine hydrochloride PLO gels for use in hospice patients for relieving symptoms such as vomiting and nausea during the end stages of life. METHODS: PLO gels of chlorpromazine hydrochloride were prepared using isopropyl palmitate (IPP) or ricinoleic acid (RA) as oil phase. In vitro percutaneous absorption of chlorpromazine hydrochloride was assessed through porcine ear and human abdominal skin. Further, the theoretical steady state plasma concentration (Css) of chlorpromazine was calculated from the flux values. RESULTS: The pH, viscosity, and stability of both PLO gels prepared with IPP and RA were comparable. The thixotropic property of RA PLO gel was found to be better than that of IPP PLO gel. The permeation of chlorpromazine hydrochloride was higher from RA PLO gel than from IPP PLO gel and pure drug solution. Theoretical Css of chlorpromazine from pure drug solution, IPP PLO gel and RA PLO gel were found to be 1.05, 1.20, and 1.50 ng/ml, respectively. PLO gels only marginally increased the flux and theoretical Css of chlorpromazine. CONCLUSION: From this study, it is clearly evident that PLO gels fail to achieve required systemic levels of chlorpromazine following topical application. Chlorpromazine PLO gel may not be effective in treating nausea and vomiting for hospice patients with swallowing difficulties.
Assuntos
Clorpromazina/administração & dosagem , Clorpromazina/metabolismo , Géis/administração & dosagem , Géis/metabolismo , Lecitinas/química , Pele/metabolismo , Abdome , Administração Cutânea , Animais , Clorpromazina/química , Sistemas de Liberação de Medicamentos/métodos , Orelha , Géis/química , Humanos , Palmitatos/química , Ácidos Ricinoleicos/química , Absorção Cutânea/fisiologia , Suínos , ViscosidadeRESUMO
Palmitoylation involves the reversible posttranslational addition of palmitate to cysteines and promotes membrane binding and subcellular localization. Recent advancements in the detection and identification of palmitoylated proteins have led to multiple palmitoylation proteomics studies but these datasets are contained within large supplemental tables, making downstream analysis and data mining time-consuming and difficult. Consequently, we curated the data from 15 palmitoylation proteomics studies into one compendium containing 1,838 genes encoding palmitoylated proteins; representing approximately 10% of the genome. Enrichment analysis revealed highly significant enrichments for Gene Ontology biological processes, pathway maps, and process networks related to the nervous system. Strikingly, 41% of synaptic genes encode a palmitoylated protein in the compendium. The top disease associations included cancers and diseases and disorders of the nervous system, with Schizophrenia, HD, and pancreatic ductal carcinoma among the top five, suggesting that aberrant palmitoylation may play a pivotal role in the balance of cell death and survival. This compendium provides a much-needed resource for cell biologists and the palmitoylation field, providing new perspectives for cancer and neurodegeneration.
Assuntos
Lipoilação , Neoplasias/metabolismo , Doenças do Sistema Nervoso/metabolismo , Palmitatos/análise , Proteoma/análise , Proteômica/métodos , Cisteína/química , Cisteína/metabolismo , Bases de Dados de Proteínas , Humanos , Palmitatos/química , Palmitatos/metabolismo , Proteoma/química , Proteoma/metabolismoRESUMO
PURPOSE: Intravenous injections of propofol emulsions are accompanied by pain likely due to the interaction of the dissolved drug with endothelial cells of the vasculature. It is commonly hypothesized that reducing the aqueous phase concentration of propofol could reduce pain. METHODS: To minimize the propofol concentration in the aqueous phase, we developed stable oil-in-water emulsions with excipient oil mixtures that have an increased partition coefficient for propofol. We then explored the emulsion stability by measuring size distributions after extended durations of shelf storage and also after freeze-thaw cycling. The effects of oil type, surfactant and salt concentration on emulsion stability were also explored. RESULTS: Small chain oils like ethyl butyrate exhibit high drug partitioning but poor stability, while larger molecules such as soybean oil exhibit lower partitioning but excellent emulsion stability. Emulsions with mixtures of soybean oil and ethyl butyrate are stable for longer than a year, resistant to freeze-thaw cycling, and reduce aqueous drug concentrations of propofol twofold compared to pure soybean oil emulsions. CONCLUSIONS: Oil-in-water emulsions of propofol formulated with mixtures of ethyl butyrate and soybean oil are kinetically stable and significantly reduce the aqueous phase drug concentration making them promising candidates for future propofol therapies.
Assuntos
Anestésicos Intravenosos/química , Hipnóticos e Sedativos/química , Propofol/química , Administração Intravenosa , Butiratos/química , Caprilatos/química , Estabilidade de Medicamentos , Emulsões , Cinética , Miristatos/química , Azeite de Oliva/química , Palmitatos/química , Poloxâmero/química , Polietilenoglicóis/química , Polissorbatos/química , Óleo de Soja/química , Tensoativos/químicaRESUMO
Alginate and low methoxylated pectin gel matrices emulsified with oleic acid were studied for phage oral delivery. Matrix structural analysis revealed that emulsified pectin (EP) gel microbeads were harder and more cohesive than those of emulsified alginate (EA). EP showed high swelling capacity and slower matrix degradation in aqueous media, suggesting that oleic acid is mainly located on the surface of EP microbeads. EA and EP matrices having p-nitrophenyl palmitate (C-16 ester) as tracer dissolved into oleic acid and in the presence of lipase confirmed this hypothesis which is consistent with EP better phage protective capability. Surface analysis of gel microbeads by scanning electron microscopy revealed strong differences between EP and EA gel microbeads. Phage release kinetics was tested using semi-empirical mathematical models. Experimental curve best fitted the Korsmeyer-Peppas model, predicting transport mechanisms according to the high swelling and degradation of EP. The proposed encapsulation model represents an innovative technology for phage therapy, which can be extrapolated to other therapeutic purposes, using a simple environmentally friendly synthesis procedure and cheap food-grade raw materials.