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1.
Nature ; 582(7813): 566-570, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555455

RESUMO

The gut microbiota synthesize hundreds of molecules, many of which influence host physiology. Among the most abundant metabolites are the secondary bile acids deoxycholic acid (DCA) and lithocholic acid (LCA), which accumulate at concentrations of around 500 µM and are known to block the growth of Clostridium difficile1, promote hepatocellular carcinoma2 and modulate host metabolism via the G-protein-coupled receptor TGR5 (ref. 3). More broadly, DCA, LCA and their derivatives are major components of the recirculating pool of bile acids4; the size and composition of this pool are a target of therapies for primary biliary cholangitis and nonalcoholic steatohepatitis. Nonetheless, despite the clear impact of DCA and LCA on host physiology, an incomplete knowledge of their biosynthetic genes and a lack of genetic tools to enable modification of their native microbial producers limit our ability to modulate secondary bile acid levels in the host. Here we complete the pathway to DCA and LCA by assigning and characterizing enzymes for each of the steps in its reductive arm, revealing a strategy in which the A-B rings of the steroid core are transiently converted into an electron acceptor for two reductive steps carried out by Fe-S flavoenzymes. Using anaerobic in vitro reconstitution, we establish that a set of six enzymes is necessary and sufficient for the eight-step conversion of cholic acid to DCA. We then engineer the pathway into Clostridium sporogenes, conferring production of DCA and LCA on a nonproducing commensal and demonstrating that a microbiome-derived pathway can be expressed and controlled heterologously. These data establish a complete pathway to two central components of the bile acid pool.


Assuntos
Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Hidroxilação/genética , Redes e Vias Metabólicas/genética , Animais , Clostridium/enzimologia , Clostridium/genética , Clostridium/metabolismo , Ácido Desoxicólico/química , Ácido Desoxicólico/metabolismo , Ácido Litocólico/química , Ácido Litocólico/metabolismo , Masculino , Engenharia Metabólica , Camundongos , Óperon/genética , Simbiose
2.
Colloids Surf B Biointerfaces ; 188: 110803, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31981815

RESUMO

Low Molecular Weight (LMWG) gelators are small molecules that form supramolecular self-assembly involving physical forces and are highly biocompatible. However, fragility of these physical gels restricts their applicability where gels of higher mechanical strength are required. Herein, we have developed two different types of 2-D carbon nanomaterials viz. graphene oxide (GO) and carbon nanosheet (CNS) embedded sodium deoxycholate (NaDC) hydrogels. XRD, scanning electron microscopy (SEM), rheology and CD studies suggest significant modification of morphological, mechanical, viscoelastic and optical properties of the nanocomposite gels which is ascribed to the presence of the 2D nanotemplates and participation of different surface functionalities of GO and CNS in the gelation process. The overall shear resistance of both the nanocomposite hydrogels upto a shear rate of 300 shears/s-1 and above reveals tremendously improved mechanical stability with respect to the pure gels. The increased shear strength of the GO/NaDC and CNS/NaDC hydrogels is attributed to their 3-4 times broader and longer ribbon like structures in comparison to the fibrous structure of pure gels. The intact ribbon like morphology and greater entanglement impart 10 folds greater viscosity to GO-NaDC hydrogels as compared to better elasticity of CNS-NaDC hydrogels possessing broken ribbon edges. Most interestingly both GO and CNS influence the optical activity of the gels and presence of GO results in inversion of optical activity. The GO-NaDC gels are also found to demonstrate antibacterial activity against E. coli, and S. aureus. Thus, these extraordinarily modified mechanically strong gels have enhanced potential for use in tissue engineering, enantioselective and sustained drug delivery, topical antibiotics and other biomedical applications.


Assuntos
Antibacterianos/farmacologia , Ácido Desoxicólico/farmacologia , Escherichia coli/efeitos dos fármacos , Hidrogéis/farmacologia , Nanocompostos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Ácido Desoxicólico/química , Liberação Controlada de Fármacos , Hidrogéis/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Testes de Sensibilidade Microbiana , Rotação Ocular , Tamanho da Partícula , Propriedades de Superfície
3.
Colloids Surf B Biointerfaces ; 185: 110594, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31715455

RESUMO

This study demonstrates that significant perturbation of tween20:cholesterol(1:1) niosome membrane takes place even at premicellar concentration of bile salts. Here, 1-naphthol (1-NpOH), a known and sensitive excited state proton transfer (ESPT) probe, was used to understand the nature of perturbation of the membrane in an unbuffered medium. The significant decrease in 1-NpOH fluorescence intensity in niosome-bile salt mixed system at both lower (10 °C) and higher (50 °C) temperatures indicates the bile salts [sodium cholate (NaC) and sodium deoxycholate (NaDC)] induce perturbation of niosome membranes. Variations in the fluorescence lifetime values of both the prototropic emissions (neutral and anionic species) along with the proton transfer rate of 1-NpOH confirm the bile salts perturb up to the hydrophobic core domain of the niosomal membranes. Bile salts induce size change of the niosomal membrane is confirmed through dynamic light scattering study.


Assuntos
Ácido Desoxicólico/química , Fluorescência , Lipossomos/química , Membranas/química , Micelas , Naftóis/química , Colato de Sódio/química
4.
Molecules ; 24(24)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31835427

RESUMO

Au nanoparticles (NPs) were prepared by UV light irradiation of a mixed solution of HAuCl4 and sodium deoxycholate (NaDC) under alkaline condition, in which NaDC served as both reducing agent and capping agent. The reaction was monitored by circular dichroism (CD) spectra, and it was found that the formed gold NPs could catalyze the oxidation of NaDC. A CD signal at ~283 nm in the UV region was observed for the oxidation product of NaDC. The intensity of the CD signal of the oxidation product was enhanced gradually with the reaction time. Electrospray ionization (ESI) mass spectra and nuclear magnetic resonance (NMR) spectra were carried out to determine the chemical composition of the oxidation product, revealing that NaDC was selectively oxidized to sodium 3-keto-12-hydroxy-cholanate (3-KHC). The chiral discrimination abilities of the micelles of NaDC and its oxidation product, 3-KHC, were investigated by using chiral model molecules R,S-1,1'-Binaphthyl-2,2'-diyl hydrogenphosphate (R,S-BNDHP). Compared with NaDC, the micelles of 3-KHC displayed higher binding ability to the chiral model molecules. In addition, the difference in binding affinity of 3-KHC micelles towards R,S-isomer was observed, and S-isomer was shown to preferentially bind to the micelles.


Assuntos
Ácidos e Sais Biliares/química , Ácido Desoxicólico/química , Ouro/química , Nanopartículas Metálicas/química , Micelas , Catálise , Nanopartículas Metálicas/ultraestrutura , Estrutura Molecular , Oxirredução , Análise Espectral
5.
Int J Nanomedicine ; 14: 6339-6356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496690

RESUMO

Objective: The rational combination of immunotherapy with standard chemotherapy shows synergistic clinical activities in cancer treatment. In the present study, an oral powder formulation of pemetrexed (PMX) was developed to enhance intestinal membrane permeability and investigate its application in metronomic chemotherapy in combination with immunotherapy. Methods: PMX was ionically complexed with a bile acid derivative (Nα-deoxycholyl-l-lysyl-methylester; DCK) as a permeation enhancer and mixed with dispersing agents, such as poloxamer 188 (P188) and Labrasol, to form an amorphous oral powder formulation of PMX/DCK (PMX/DCK-OP). Results: The apparent permeability (Papp) of PMX/DCK-OP across a Caco-2 cell monolayer was 2.46- and 8.26-fold greater than that of PMX/DCK and free PMX, respectively, which may have been due to the specific interaction of DCK with bile acid transporters, as well as the alteration of membrane fluidity due to Labrasol and P188. Furthermore, inhibition of bile acid transporters by actinomycin D in Caco-2 cell monolayers decreased the Papp of PMX/DCK-OP by 75.4%, suggesting a predominant role of bile acid transporters in the intestinal absorption of PMX/DCK-OP. In addition, caveola/lipid raft-dependent endocytosis, macropinocytosis, passive diffusion, and paracellular transport mechanisms significantly influenced the permeation of PMX/DCK-OP through the intestinal membrane. Therefore, the oral bioavailability of PMX/DCK-OP in rats was 19.8%±6.93%, which was 294% higher than that of oral PMX. Moreover, an in vivo anticancer efficacy study in B16F10 cell-bearing mice treated with a combination of oral PMX/DCK-OP and intraperitoneal anti-PD1 exhibited significant suppression of tumor growth, and the tumor volume was maximally inhibited by 2.03- and 3.16-fold compared to the oral PMX/DCK-OP and control groups, respectively. Conclusion: These findings indicated the therapeutic potential of a combination of low-dose oral chemotherapy and immunotherapy for synergistic anticancer efficacy.


Assuntos
Ácido Desoxicólico/química , Composição de Medicamentos , Intestinos/efeitos dos fármacos , Pemetrexede/farmacologia , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Disponibilidade Biológica , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/química , Humanos , Íons , Lisina/análogos & derivados , Lisina/química , Camundongos Endogâmicos BALB C , Pemetrexede/administração & dosagem , Pemetrexede/sangue , Pemetrexede/farmacocinética , Permeabilidade , Ratos Sprague-Dawley
6.
AAPS PharmSciTech ; 20(7): 302, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31489504

RESUMO

Docetaxel (DTX) was effective in the treatment of neoplasm but could only be administered intravenously with the poor oral bioavailability owing to its undesirable solubility, remarkably metabolic conversion, and other factors. Cimetidine (CMD), a classic CYP3A4 isozyme inhibitor, had exhibited a wide range of inhibition on the metabolism of many drugs. The aim of this study was to construct the novel docetaxel-cimetidine (DTX-CMD) complex and the chitosan-deoxycholate nanoparticles based on it to confirm whether this formulation could show advantages in terms of solubility, dissolution rate, small intestinal absorption, and oral bioavailability in comparison with the pure drug. The solid-state characterization was carried out by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), and simultaneous DSC-TGA (SDT). Dissolution rate and kinetic solubility study were determined by evaluating the amount of DTX in distilled water and phosphate buffer solution (pH = 7.4), respectively. And small intestinal absorption and pharmacokinetics study were conducted in rats. The results of this study demonstrated that we successfully constructed DTX-CMD complex and its chitosan-deoxycholate nanoparticles. Furthermore, the DTX-CMD complex increased the solubility of DTX by 2.3-fold and 2.1-fold in distilled water and phosphate buffer solution, respectively. The ultimate accumulative amount of DTX-CMD complex nanoparticles through rat small intestinal in 2 h was approximately 4.9-fold and the oral bioavailability of the novel nanoparticles was enhanced 2.8-fold, compared with the pure DTX. The superior properties of the complex nanoparticles could both improve oral bioavailability and provide much more feasibility for other formulations of DTX.


Assuntos
Antineoplásicos/química , Cimetidina/química , Docetaxel/química , Administração Oral , Animais , Disponibilidade Biológica , Quitosana/química , Cimetidina/farmacocinética , Ácido Desoxicólico/química , Docetaxel/farmacocinética , Composição de Medicamentos , Masculino , Nanopartículas/química , Ratos , Ratos Sprague-Dawley , Solubilidade
7.
Carbohydr Polym ; 223: 115118, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426975

RESUMO

New biocompatible amphiphilic block copolymers were prepared using two natural compounds as starting materials, a polysaccharide (dextran) and a bile acid (deoxycholic acid). The copolymers were synthesized by dipolar 1,3-cycloaddition reaction between dextran with azide end groups and deoxycholic acid - oligo(ethylene glycol)s polyester with propargyl end groups. Different copolymer composition were obtained by variation of molecular weights of dextran (Mn 4.5, 8, 15 kDa) and polyester (Mn 2-6 kDa), as well as the length of oligo(ethylene glycol) (2-4 ethylenglycol units) used for polyester synthesis. These copolymers can for micelle like aggregates in aqueous medium with nanometric size (50-600 nm) and spherical form, as assessed by light scattering, atomic force microscopy and transmission electron microscopy. Encapsulation of the hydrophobic drug curcumin in micelles could increase 68,181 times its water solubility, and curcumin release from micelles was slow and with reduced burst effect.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Curcumina/química , Ácido Desoxicólico/química , Dextranos/química , Polímeros/síntese química , Tensoativos/síntese química , Materiais Biocompatíveis/química , Cápsulas/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Micelas , Conformação Molecular , Tamanho da Partícula , Polímeros/química , Solubilidade , Propriedades de Superfície , Tensoativos/química
8.
Int J Biol Macromol ; 139: 665-677, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377298

RESUMO

Sorafenib (SF) a chemotherapeutic drug is used in hepatocellular carcinoma (HCC) with vast side effects. The aim of the project ahead was synthesis of SF loaded co-polymeric micelles of pectin-deoxycholic acid (P-DOCA) to target the overexpressed asialoglycoprotein receptors of hepatocytes by pectin. DOCA was modified with ethylenediamine and conjugated to pectin. FT-IR and 1HNMR confirmed the bio-conjugation. Pyrene was used to measure critical micelle concentration (CMC) by fluorimetry technique. P-DOCA micelles were loaded with SF and their particle size, zeta potential, drug loading and release efficiency were measured. MTT assay was used for determining cytotoxicity. The cell cycle arrest was studied by flow cytometry analysis and the cellular uptake was studied using cumarin-6 as the fluorophore agent. The micelles capability in preventing the cells migration was tested by Transwell plates. The CMC of P-DOCA micelles was 10.747 µg/mL. The best formulation obtained from SF to polymer ratio of 1:2. SF loaded micelles showed 30% increased cytotoxicity. The micelles cellular uptake was more than the free drug. Relative migration of HepG2 cells treated with SF loaded micelles was reduced to 6.67% compared to free SF which was 26.67%. The designed micelles are promising for antitumor drug targeting to HCC.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/patologia , Ácido Desoxicólico/química , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas/patologia , Pectinas/química , Sorafenibe/administração & dosagem , Receptor de Asialoglicoproteína/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Ciclo Celular , Movimento Celular , Proliferação de Células , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Micelas , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos , Temperatura , Fatores de Tempo
9.
Int J Biol Macromol ; 139: 1035-1045, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412265

RESUMO

Colorectal cancer (CRC) is a prevalent and fatal cancer. Oral administration provided the potential for in situ treatment of the colorectal cancer. However, drugs couldn't be well-absorbed mainly due to its degradation in the gastric area and poor intestinal permeability. In this study, we synthesized deoxycholic acid and hydroxybutyl decorated chitosan nanoparticles (DAHBC NPs) as oral curcumin (CUR) delivery system for colorectal cancer treatment. DAHBC with lower critical solution temperature (LCST) below 37 °C (27-33 °C) was obtained. DAHBC NPs were correspondingly stable in simulated gastric conditions (pH 1.2, 37 °C), due to the offset of size change between pH-responsive expansion and thermo-responsive shrinkage. In simulated intestinal tract (pH 7.0-7.4, 37 °C), DAHBC NPs exhibited burst release of CUR owing to the onefold effect of thermo-responsive shrinkage. DAHBC27 NPs showed the minimum CUR leakage (~10%) in simulated gastric conditions, because a furthest temperature-sensitive shrinkage caused by the lowest LCST offset the expansion in acid environment. DAHBC27 NPs induced ~10-fold increased (P < 0.05) CUR absorption by paracellular transport pathway, compared to the free CUR. Thus, DAHBC NPs stabilized in the gastric environment may be a promising oral drugs delivery system for effective in situ colorectal cancer therapy.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Curcumina/administração & dosagem , Curcumina/química , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Mucosa Gástrica/metabolismo , Administração Oral , Adsorção , Células CACO-2 , Quitosana/análogos & derivados , Quitosana/química , Curcumina/uso terapêutico , Ácido Desoxicólico/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Hemólise/efeitos dos fármacos , Humanos , Absorção Intestinal , Teste de Materiais , Nanopartículas/química , Temperatura
10.
Colloids Surf B Biointerfaces ; 183: 110406, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31401462

RESUMO

Amphotericin B is used for local delivery from polymethylmethacrylate to treat fungal prosthetic joint infections. The optimal amphotericin B formulation and the influence of different poragens in the bone cements are unknown. To investigate the necessary amount of amphotericin B in the bone cement to prevent Candida biofilm several amphotericin B formulations were studied: non-liposomal and liposomal with or without poragen gentamicin. For the non-liposomal formulation, standard bile salt, the sodium deoxycholate, was used and additionally N-methyl-D-glucamine/palmitate was applied. The activity of the released amphotericin B was tested against C. albicans, C. glabrata, C. parapsilosis and C. krusei biofilms with application of the isothermal calorimeter and standard microbiological methods. Compressive strength was measured before and after antifungal elution from the cements. There is less aggregated N-methyl-D-glucamine/palmitate amphotericin B released but its antifungal activity is equivalent with the deoxycholate amphotericin B. The minimum quantity of antifungal preventing the Candida biofilm formation is 12.5 mg in gram of polymer powder for both non-liposomal formulations. The addition of gentamicin reduced the release of sodium deoxycholate amphotericin B. Gentamicin can be added to N-methyl-D-glucamine/palmitate amphotericin B in order to boost the antifungal release. When using liposomal amphotericin B more drug is released. All amphotericin B formulations were active against Candida biofilms. Although compressive strength slightly decreased, the obtained values were above the level of strength recommended for the implant fixation. The finding of this work might be beneficial for the treatment of the prosthetic joint infections caused by Candida spp.


Assuntos
Anfotericina B/análogos & derivados , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Ácido Desoxicólico/farmacologia , Anfotericina B/química , Antifúngicos/química , Biofilmes/crescimento & desenvolvimento , Cimentos para Ossos/análise , Cimentos para Ossos/química , Candida albicans/crescimento & desenvolvimento , Candida glabrata/efeitos dos fármacos , Candida glabrata/crescimento & desenvolvimento , Candida parapsilosis/efeitos dos fármacos , Candida parapsilosis/crescimento & desenvolvimento , Força Compressiva , Ácido Desoxicólico/química , Combinação de Medicamentos , Liberação Controlada de Fármacos , Gentamicinas/farmacologia , Cinética , Teste de Materiais , Testes de Sensibilidade Microbiana , Polimetil Metacrilato/análise , Polimetil Metacrilato/química , Porosidade
11.
PLoS One ; 14(8): e0221052, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31415606

RESUMO

Protein solubility is a critical prerequisite to any proteomics analysis. Combination of urea/thiourea and 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) have been routinely used to enhance protein solubilization for oil palm proteomics studies in recent years. The goals of these proteomics analysis are essentially to complement the knowledge regarding the regulation networks and mechanisms of the oil palm fatty acid biosynthesis. Through omics integration, the information is able to build a regulatory model to support efforts in improving the economic value and sustainability of palm oil in the global oil and vegetable market. Our study evaluated the utilization of sodium deoxycholate as an alternative solubilization buffer/additive to urea/thiourea and CHAPS. Efficiency of urea/thiourea/CHAPS, urea/CHAPS, urea/sodium deoxycholate and sodium deoxycholate buffers in solubilizing the oil palm (Elaeis guineensis var. Tenera) mesocarp proteins were compared. Based on the protein yields and electrophoretic profile, combination of urea/thiourea/CHAPS were shown to remain a better solubilization buffer and additive, but the differences with sodium deoxycholate buffer was insignificant. A deeper mass spectrometric and statistical analyses on the identified proteins and peptides from all the evaluated solubilization buffers revealed that sodium deoxycholate had increased the number of identified proteins from oil palm mesocarps, enriched their gene ontologies and reduced the number of carbamylated lysine residues by more than 67.0%, compared to urea/thiourea/CHAPS buffer. Although only 62.0% of the total identified proteins were shared between the urea/thiourea/CHAPS and sodium deoxycholate buffers, the importance of the remaining 38.0% proteins depends on the applications. The only observed limitations to the application of sodium deoxycholate in protein solubilization were the interference with protein quantitation and but it could be easily rectified through a 4-fold dilution. All the proteomics data are available via ProteomeXchange with identifier PXD013255. In conclusion, sodium deoxycholate is applicable in the solubilization of proteins extracted from oil palm mesocarps with higher efficiency compared to urea/thiourea/CHAPS buffer. The sodium deoxycholate buffer is more favorable for proteomics analysis due to its proven advantages over urea/thiourea/CHAPS buffer.


Assuntos
Arecaceae/química , Ácido Desoxicólico/química , Detergentes/química , Óleo de Palmeira/química , Proteínas de Plantas/análise , Proteômica , Tampões (Química) , Ácidos Cólicos/química , Proteínas de Plantas/química
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117326, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31302566

RESUMO

The present investigation reports a detailed characterization of the interaction of a cationic photosensitizer, phenosafranin (PSF) with sodium deoxycholate (NaDC) bile salt aggregates based on spectroscopic and calorimetric techniques. Our explicit spectroscopic results not only establish the occurrence of PSF-NaDC binding interaction, but also reveal marked lowering of micropolarity at the interaction site (ET(30) = 55.97 kcal mol-1 in the presence of NaDC as compared to ET(30) = 63.1 kcal mol-1 in bulk aqueous buffer). A thorough mathematical analysis of the fluorescence depolarization results based on the two-step and wobbling in cone model yields critical insight into the complex rotational relaxation dynamics of the bound drug. The impartation of motional restriction on the PSF molecules within the bile salt aggregates is evidenced from enhancement of average rotational correlation time from <τr> = 136 ps in aqueous buffer to 1.11 ns with added NaDC (8.0 mM). This is further supported from a high value of the generalized order parameter (S = 0.81) as well as the diffusion coefficient (Dw = 1.40 × 1012 s-1). Furthermore, our extensive calorimetric investigation unveils the complicated thermodynamics of the interaction process in terms of predominant entropic contribution over the enthalpic part in the lower temperature regime (TΔS = 18.84 ±â€¯1.13 kJ mol-1, ΔH = -5.82 ±â€¯0.35 kJ mol-1 at 288 K) with subsequent reversal of the relative contributions with increasing temperature (TΔS = 7.54 ±â€¯0.39 kJ mol-1, ΔH = - 17.09 ±â€¯0.90 kJ mol-1 at 318 K). The instrumental role of the hydrophobic effect underlying the PSF-NaDC interaction is characterized by a negative heat capacity change (ΔCp = -364 J mol-1 K-1). An intriguing thermodynamic feature in terms of enthalpy-entropy compensation (with increasing temperature ΔG remains almost constant while ΔH and TΔS vary significantly) aptly corroborates the aforesaid argument and establishes an appreciable hydrophobic contribution to the overall binding energies.


Assuntos
Ácidos e Sais Biliares/química , Fármacos Fotossensibilizantes/química , Anisotropia , Calorimetria , Cátions , Ácido Desoxicólico/química , Entropia , Fenazinas/química , Espectrometria de Fluorescência , Termodinâmica , Fatores de Tempo
13.
PLoS One ; 14(7): e0219752, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31310613

RESUMO

Daclatasvir is a new direct acting antiviral used in treatment of Hepatitis C virus, in an attempt to increase its hepatocytes specificity and uptake. It was encapsulated within bile based vesicles (BBVs) containing egg phosphatidyl choline, cholesterol and sodium deoxycholate fabricated by thin-film hydration method. A D-optimal mixture design was applied to study the effect of formulation variables on vesicular characteristics. The dependent variables picked were the particle size, polydispersity index, zeta potential and entrapment efficiency. The optimized bile based vesicles were subjected for further modifications to prepare miniaturized anionic (ABBVs), cationic (CBBVs) and Sito-G decorated BBVs (Sito-GBBVs) to be capable to penetrate liver fenestrae (<200 nm). The aim of the current work is to compare the potential of the ABBVs, CBBVs and Sito-GBBVs loaded with Daclatasvir for stability in simulated biological fluids, ex-vivo intestinal transenterocytic transport, HepG2 cellular uptake and resistance to blood protein adsorption. The miniaturized ABBVs, CBBVs and Sito-GBBVs showed acceptable stability in simulated biological fluids. CBBVs had the highest transenterocytic transport through intestinal membrane. The internalization of CBBVs into HepG2 cells was about 2.1 folds that of ABBVs and 1.45 folds that of Sito-GBBVs. ABBVs and Sito-GBBVs showed superior resistance to opsonization compared to CBBVs which showed significant increase in particle size (p˃0.05) due to protein adsorption. The miniaturized Sito-GBBVs constitute a promising strategy to overcome key biological barriers facing hepatocytes specific delivery of Daclatasvir.


Assuntos
Antivirais/administração & dosagem , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Hepatócitos/efeitos dos fármacos , Imidazóis/administração & dosagem , Sitosteroides/química , Adsorção , Animais , Transporte Biológico , Colesterol/química , Ácido Desoxicólico/química , Células Hep G2 , Humanos , Lipossomos/química , Fígado/efeitos dos fármacos , Masculino , Tamanho da Partícula , Fosfatidilcolinas/química , Ratos , Ratos Wistar
14.
Colloids Surf B Biointerfaces ; 182: 110374, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330430

RESUMO

This work presents the outcomes of a comparative study of molecular interactions of polymyxin B (PMB) and F12 and F13 formulations in the mole ratios of 1:2 and 1:3 of PMB:sodium deoxycholate sulfate (SDCS), respectively, and a commercial PMB formulation (CPMB) with lipopolysaccharides (LPS). Several spectroscopic and interfacial studies were performed to obtain LPS-peptide interactions at a molecular level. The fluorescence titrimetry method revealed that the F12 formulation (325 nM) exhibited a lower number of binding sites to the LPS compared to CPMB and F13 as well as PMB alone (537 nM). Similarly, in the presence of LPS, the F12 formulation (88 nm) exhibited smaller particle sizes in the dynamic light scattering study compared to PMB (116 nm), CPMB, and the F13 formulation. An interfacial study and circular dichroism spectroscopy revealed PMB and CPMB insertion into the LPS micelles to destabilize and disrupt the LPS membrane, whereas the F12 and F13 formulations may induce pseudo-aggregation. The NMR and IR studies showed that the presence of SDCS, the hydrophobicity of PMB increased by hydrogen bonding and electrostatic interactions and formed stabilized PMB-SDCS micelles. The PMB-SDCS formulation is likely to release PMB for easy penetration into the lipid membrane and cause disruption of the complex LPS micelles. Furthermore, the PMB-SDCS formulations neutralized and detoxified the LPS micelles with minimal toxicity to normal kidney tubular cells as well as an immortalised kidney cell line. The antimicrobial properties of PMBloaded SDCS nanomicelles were effective against a resistant strain of Pseudomonas aeruginosa.


Assuntos
Ácido Desoxicólico/química , Lipopolissacarídeos/química , Polimixina B/química , Sulfatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ácido Desoxicólico/metabolismo , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Escherichia coli/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Polimixina B/metabolismo , Polimixina B/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Eletricidade Estática , Sulfatos/metabolismo
15.
Molecules ; 24(14)2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31330911

RESUMO

A series of novel deoxycholic acid (DCA) derivatives containing aliphatic diamine and aminoalcohol or morpholine moieties at the C3 position were synthesized by 3,26-epoxide ring-opening reactions. These compounds were investigated for their cytotoxicity in four human tumor cell lines and murine macrophages and for inhibitory activity against macrophage-mediated NO synthesis in vitro. Obtained data revealed that: (i) all amine-containing substituents significantly increased the cytotoxicity of the novel compounds (IC502-10 = 1.0-36.0 µM) in comparison with DCA (IC50DCA ≥ 82.9 µM); (ii) aminoalcohol moieties were more preferable than diamine moieties due to the fact they imparted better selectivity for tumor cells of the novel derivatives; (iii) the susceptibility of tested cell lines to derivatives diminished in the following order: HuTu-80 (duodenal carcinoma) ≈ HepG2 (hepatocarcinoma) > KB-3-1 (cervical carcinoma) > RAW264.7 (macrophages) > A549 (lung carcinoma); (iv) compounds 8 and 9, bearing aminoethanol and aminopropanol moieties, respectively, exhibited high cytotoxic selectivity indexes (SIHuTu-80 = 7.9 and 8.3, respectively) and good drug-likeness parameters; (v) the novel compounds do not display anti-NO activity. Mechanistic study revealed that compound 9 induces ROS-dependent cell death by activation of intrinsic caspase-dependent apoptosis and cytodestructive autophagy in HuTu-80 cells and vitamin D receptor can be considered as its primary target.


Assuntos
Amino Álcoois/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Ácido Desoxicólico/química , Ácido Desoxicólico/farmacologia , Diaminas/química , Animais , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Ácido Desoxicólico/síntese química , Relação Dose-Resposta a Droga , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Relação Estrutura-Atividade
16.
Int J Nanomedicine ; 14: 4123-4131, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239671

RESUMO

Purpose: The objective of this work was to formulate a delivery system of pDNA encoded p53 gene-loaded chitosan-sodium deoxycholate (CS-DS) nanoparticles, and to evaluate their influence on in vitro cytotoxicity and transfection efficiency of p53 gene. Methods: The prepared pDNA-loaded CS-DS nanoparticles were evaluated for morphology, particle size, zeta potential, entrapment efficiency %, in vitro release, in vitro cytotoxicity, and transfection efficiency. Results: The mean particle size ranged from from 96.5 ± 11.31 to 405 ± 46.39 nm. All nanoparticles had good positive zeta potential values. Entrapment efficiency % ranged from 38.25 ± 3.25 to 94.89 ± 5.67. The agarose gel electrophoresis confirmed the strong binding between plasmid and CS. The in vitro pDNA release from nanoparticles exhibited an initial burst effect followed by a sustained drug release over a period of 6 days. In vitro cytotoxicity against human Caco-2 cells showed low cell cytotoxicity of plain CS-DS nanoparticles, while pDNA-loaded CS-DS nanoparticles showed a cytotoxic effect with increasing nanoparticles' concentration. Gene transfection, analyzed by PCR and ELISA, showed a direct correlation between gene expression and concentration of pDNA. The highest expression of the gene was achieved with pDNA concentration of 9 µg/mL with 5.7 times increase compared to naked pDNA of the same concentration. Conclusion: The obtained results were very encouraging and offer an alternative approach to enhancing the transfection efficiency of genetic material-loaded chitosan-based delivery systems.


Assuntos
Quitosana/química , DNA/genética , Ácido Desoxicólico/química , Nanopartículas/química , Plasmídeos/metabolismo , Transfecção , Proteína Supressora de Tumor p53/genética , Células CACO-2 , Morte Celular , Liberação Controlada de Fármacos , Humanos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática
17.
Int J Nanomedicine ; 14: 3679-3689, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239660

RESUMO

Background and purpose: Conventional topical ophthalmic aqueous solutions and suspensions are often associated with low bioavailability and high administration frequency, pulsatile dose and poor exposure to certain ocular parts. The aim of this study was to develop an ophthalmic nanoparticles loaded gel, for delivering prednisolone acetate (PA), to increase dosing accuracy, bioavailability, and accordingly, efficiency of PA in treating inflammatory ocular diseases. Methods: A novel formulation of self-assembled nanoparticles was prepared by the complexation of chitosan (CS) and, the counter-ion, sodium deoxycholate (SD), loaded with the poorly-water-soluble PA. Particle size, zeta potential, encapsulation efficiency (EE) and drug loading content (LC) of prepared nanoparticles were assessed. Moreover, the nanoparticles were characterized using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Drug release and eye anti-inflammatory potential of the prepared novel formulation was investigated. Results: Mean particle size of the nanoparticles have dropped from 976 nm ±43 (PDI 1.285) to 480 nm ±28 (PDI 1.396) when the ratio of CS-SD was decreased. The incorporation of 0.1-0.3% of polyvinyl alcohol (PVA), in the preparation stages, resulted in smaller nanoparticles: 462 nm ±19 (PDI 0.942) and 321 nm ±22 (PDI 0.454) respectively. DSC and FTIR results demonstrated the interaction between CS and SD, however, no interactions were detected between PA and CS or SD. Drug release of PA as received, in simulated tears fluid (pH 7.4), showed a twofold increase (reaching an average of 98.6% in 24 hours) when incorporated into an optimized nanoparticle gel formulation (1:5 CS-SD). Conclusion: The anti-inflammatory effect of PA nanoparticles loaded gel on female guinea pig eyes was significantly superior to that of the micronized drug loaded gel (P < 0.05).


Assuntos
Anti-Inflamatórios/farmacologia , Quitosana/química , Ácido Desoxicólico/química , Olho/efeitos dos fármacos , Olho/patologia , Nanopartículas/química , Prednisolona/análogos & derivados , Animais , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Feminino , Cobaias , Inflamação/patologia , Nanopartículas/ultraestrutura , Tamanho da Partícula , Prednisolona/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Ovarian Res ; 12(1): 58, 2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31228949

RESUMO

BACKGROUND: In order to preserve fertility in young women with disseminated cancer, e.g. leukemia, an approach that has been suggested is to retransplant isolated small follicles within an ovarian matrix free from malignant cells and with no risk for contamination. The present study evaluates the first step to create a bioengineered ovarian construct that can act as growth-supporting tissue for isolated small follicles that are dependent on a stroma for normal follicular maturation. The present study used the intact mouse ovary to develop a mouse ovarian scaffold through various protocols of decellularization. MATERIAL AND METHODS: Potential Immunogenic DNA and intracellular components were removed from whole mouse ovaries by agitation in a 0.5% sodium dodecyl sulfate solution (Protocol 1; P1), or in a 2% sodium deoxycholate solution (P2) or by a combination of the two (P3). The remaining decelluralized ovarian extracellular matrix structure was then assessed based on the DNA- and protein content, and was further evaluated histologically by haematoxylin and eosin-, Verhoeff's van gieson- (for elastin), Masson's trichrome- (for collagens) and Alcian blue (for glycosaminoglycans) staining. We also evaluated the decellularization efficiency using the mild detergent Triton-X100 (1%). RESULTS: Sodium dodecyl sulfate efficiently removed DNA and intracellular components from the ovarian tissue but also significantly reduced the integrity of the remaining ovarian extracellular matrix. Sodium deoxycholate, a considerably milder detergent compared to sodium dodecyl sulfate, preserved the ovarian extracellular matrix better, evident by a more distinct staining for glycosaminoglycan, collagen and elastic fibres. Triton-X100 was found ineffective as a decellularization reagent for mouse ovaries in our settings. CONCLUSIONS: The sodium dodecyl sulfate generated ovarian scaffolds contained minute amounts of DNA that may be an advantage to evade a detrimental immune response following engraftment. The sodium deoxycholate generated ovarian scaffolds had higher donor DNA content, yet, retained the extracellular composition better and may therefore have improved recellularization and other downstream bioengineering applications. These two novel types of mouse ovarian scaffolds serve as promising scaffold-candidates for future ovarian bioengineering experiments.


Assuntos
Ovário/citologia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Órgãos Bioartificiais , DNA/análise , DNA/isolamento & purificação , Ácido Desoxicólico/química , Matriz Extracelular/química , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Ovário/química , Dodecilsulfato de Sódio/química
19.
Carbohydr Polym ; 219: 143-154, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151511

RESUMO

In recent years, the utilization of polysaccharides as targeted drug carriers has attracted considerable attention. Herein, Angelica sinensis polysaccharide (ASP), a plant polysaccharide with good biocompatibility, excellent aqueous solubility and intrinsic liver-targeted capability, was modified with hydrophobic group (deoxycholic acid) to fabricate amphiphilic conjugate (ASP-DOCA). Self-assembled nanoparticles were successfully developed for hepatoma-targeted delivery of therapeutic drug doxorubicin (DOX). The DOX loaded nanoparticles (DOX/ASP-DOCA NPs) were spherical in shape with a particle size of 228 nm and negatively charged around -17 mV. DOX was released from nanoparticles in a sustainable and pH-dependent manner. In vitro cellular uptake revealed that DOX/ASP-DOCA NPs were internalized into HepG2 cells through asialoglycoprotein receptor (ASGPR)-mediated endocytosis, resulting in a higher anti-proliferation effect than DOX-loaded dextran derivative DOX/DEX-DOCA NPs. Additionally, DOX/ASP-DOCA NPs showed higher inhibition on the growth of HepG2 multicellular spheroids (MCs) than DOX/DEX-DOCA NPs. In vivo imaging demonstrated that ASP-DOCA NPs specifically targeted HepG2 tumors via ASGPR, improving the accumulation of DOX/ASP-DOCA NPs in tumors and generating superior antitumor activity compared with free DOX and DOX/DEX-DOCA NPs. Taken together, ASP-DOCA NPs possess potential applications in drug delivery systems targeting liver cancer.


Assuntos
Angelica sinensis/metabolismo , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanoconjugados/uso terapêutico , Nanopartículas/uso terapêutico , Polissacarídeos/uso terapêutico , Animais , Receptor de Asialoglicoproteína/metabolismo , Ácido Desoxicólico/química , Células HeLa , Células Hep G2 , Humanos , Camundongos , Nanopartículas/ultraestrutura , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
20.
Eur J Med Chem ; 178: 458-467, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202993

RESUMO

The liver X receptors (LXRs) of the nuclear receptor family are promising therapeutic targets of multiple diseases like lipid disorders, chronic inflammation, as well as different human cancers. To date, no LXR agonists or antagonists can be used in clinics, emphasizing the importance for discovering new LXR modulators. Fragment-based lead discovery (FBLD) is powerful for designing new scaffolds and new mechanistic drugs, but fragment screening has not been applied to LXRs yet, which might be due to the lack of a specific fragment screening method against the dynamic and hydrophobic ligand binding domain (LBD) of LXRs. Herein, a series of fluorescent tracers were designed, synthesized and tested. The tracer based on hyodeoxycholic acid exhibited a good capability for competitively detecting the ligand binding of LXRß using a fluorescence polarization approach. Then, 1074 fragments were screened against the LBD of LXRß (LXRß-LBD), resulting in 27 binding hits. These fragment hits were further tested using the co-activator recruitment assay and reporter gene assay, and efforts in X-ray crystallography fortunately solved a co-crystal structure of LXRß-LBD with the fragment F3 (tert-butyl-7-amino-3,4-dihydroisoquinoline-2(1H)-carboxylate). The fluorescence-based fragment screening tool and the newly identified LXRß binding fragments provide the basis for developing novel LXRß modulators.


Assuntos
Ácido Desoxicólico/farmacologia , Polarização de Fluorescência , Corantes Fluorescentes/farmacologia , Receptores X do Fígado/antagonistas & inibidores , Cristalografia por Raios X , Ácido Desoxicólico/síntese química , Ácido Desoxicólico/química , Relação Dose-Resposta a Droga , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Receptores X do Fígado/metabolismo , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
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