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1.
Int J Biol Macromol ; 253(Pt 2): 126652, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37673169

RESUMO

Channelopathies arise from ion channel dysfunction. Successful treatment entails delivery of functional ion channels to replace dysfunctional ones. Glycine receptor (GlyR)-rich cell membrane fragments (CMF) were previously delivered to target cell membranes using fusogenic liposomes. Here, cystic fibrosis transmembrane conductance regulator (CFTR)-bearing CMF were similarly delivered to target cells. We studied the effect of lipid composition on liposomes' ability to incorporate CMF and fuse with target cell membranes to deliver functional CFTR. Four formulations were prepared using thin-film hydration out of different lecithin sources, egg and soy lecithin (EL and SL), in the presence and absence of cholesterol (CHOL): EL + CHOL, EL-CHOL, SL + CHOL, and SL-CHOL. EL liposomes incorporated more CMF than SL liposomes, with CHOL only increasing CMF incorporation in SL liposomes. SL + CHOL fused better with target cell membranes than EL + CHOL. SL + CHOL and EL + CHOL equally delivered CFTR to target cell membranes, owing to the former's superior fusogenic capacity and the latter's superior CMF-incorporation capacity. SL-CHOL and EL-CHOL delivered CFTR to a lesser extent, indicating the importance of CHOL for fusion. Patch-clamp electrophysiology and confocal laser scanning microscopy (CLSM) confirmed CFTR delivery to target cell membranes by SL + CHOL. Therefore, CMF-bearing fusogenic liposomes offer a promising universal platform for the treatment of channelopathies.


Assuntos
Canalopatias , Fibrose Cística , Humanos , Lipossomos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Lecitinas , Canalopatias/tratamento farmacológico
2.
Biomed Mater ; 18(1)2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36541457

RESUMO

Metabolic reprogramming 'Warburg effect' and immune checkpoint signaling are immunosuppressive hallmarks of triple-negative breast cancer (TNBC) contributing to the limited clinical applicability of immunotherapy. Biomaterials arise as novel tools for immunomodulation of the tumor microenvironment that can be used alongside conventional immunotherapeutics. Chitosan and lecithin are examples of versatile biomaterials with interesting immunomodulatory properties. In this study, we aimed at investigation of the role of carefully designed hybrid nanoparticles (NPs) on common mediators of both programmed death ligand 1 (PD-L1) expression and glycolytic metabolism. Hybrid lecithin-chitosan NPs were prepared and characterized. Their intracellular concentration, localization and effect on the viability of MDA-MB-231 cells were assessed. Glycolytic metabolism was quantified by measuring glucose consumption, adenosine triphosphate (ATP) generation, lactate production and extracellular acidification. Nitric oxide production was quantified using Greiss reagent. Gene expression of inducible nitric oxide synthase (iNOS), phosphatidylinositol-3-kinase (PI3K), protein kinase B (PKB or Akt), mammalian target of rapamycin (mTOR), hypoxia-inducible factor 1α(HIF-1α) and PD-L1 was quantified by quantitative reverse transcription polymerase chain reaction (q-RT-PCR). Chitosan, lecithin and the NPs-formulated forms have been shown to influence the 'Warburg effect' and immune checkpoint signaling of TNBC cells differently. The composition of the hybrid systems dictated their subcellular localization and hence the positive or negative impact on the immunosuppressive characteristics of TNBC cells. Carefully engineered hybrid lecithin-chitosan NPs could convert the immune-suppressive microenvironment of TNBC to an immune-active microenvironment via reduction of PD-L1 expression and reversal of the Warburg effect.


Assuntos
Quitosana , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/genética , Antígeno B7-H1 , Lecitinas , Materiais Biocompatíveis , Microambiente Tumoral
3.
Clin J Pain ; 35(4): 328-334, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30829734

RESUMO

OBJECTIVES: Continuous wound infiltration of local anesthetics has been proposed as an alternative to epidural analgesia during abdominal surgery. Cytokines have a major role in inflammatory changes caused by surgery. This study aimed to compare the effects of continuous preperitoneal versus epidural analgesia on inflammatory cytokines postoperatively. MATERIALS AND METHODS: Forty patients scheduled for radical cystectomy were included in this observer-blinded, randomized trial; patients were randomly assigned into 2 groups to receive; continuous preperitoneal wound infiltration (PPB) or epidural analgesia (EDB). Serum levels of interleukins (IL1ß, IL6, IL10, and tumor necrosis factor α) were measured at baseline (before induction of anesthesia), preinfusion (before the start of local anesthetic infusion), 6 and 24 hours postoperatively. Visual Analog Scale at rest/movement (VAS-R/M), time to the first request of analgesia, total morphine consumption, sedation score, hemodynamics, and side effects were observed 24 hours postoperatively. RESULTS: There was a significant reduction in IL6, IL1ß and increase in IL10 in PPB compared with EDB at 6 and 24 hours postoperatively and compared with preinfusion levels (P≤0.001). In EDB, a significant increase in IL1ß, IL10, and tumor necrosis factor α at 6 hours compared with preinfusion levels (P≤0.002). VAS-R/M was significantly decreased at 2, 4, 6, 8, and 12 hours in EDB compared with PPB (P≤0.014), with no significant difference in the mean time to the first request of analgesia and total morphine consumption between the 2 groups. CONCLUSION: Continuous preperitoneal analgesia better attenuated postoperative inflammatory response and provided a comparable overall analgesia to that with continuous epidural analgesia following radical cystectomy.


Assuntos
Analgesia Epidural/métodos , Analgesia/métodos , Inflamação/patologia , Infusões Parenterais , Dor Pós-Operatória/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Adolescente , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/uso terapêutico , Anestesia Local , Anestésicos Locais/administração & dosagem , Cistectomia/efeitos adversos , Feminino , Humanos , Interleucinas/sangue , Lidocaína/administração & dosagem , Masculino , Pessoa de Meia-Idade , Morfina/administração & dosagem , Morfina/uso terapêutico , Medição da Dor , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Prospectivos , Adulto Jovem
4.
Eur J Pharm Biopharm ; 134: 96-106, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30471341

RESUMO

Preventing hepatic stellate cell (HSC) activation represents a promising approach to resolve liver fibrosis. Several drugs have been reported to delay/prevent HSCs activation, however with limited clinical benefits. The latter may be in part attributed to the limited ability of such drugs in targeting more than one pathway of HSC activation. Added to that, is their inability of reaching their target cell in sufficient amounts to induce a therapeutic effect. In this work, chitosan NPs were loaded with JQ1 and atorvastatin, two drugs that have been reported to prevent HSCs activation, however via different mechanisms. NPs were then modified with different densities of retinol (Rt) for active targeting of HSCs. The NP HSCs targeting ability as a function of Rt density was assessed in vitro on primary HSCs and in vivo in carbon tetrachloride (CCl4) induced fibrotic mouse models. In vitro NPs modified with a low Rt density (LRt-NPs) showed ≈2 folds enhanced HSCs uptake in comparison to unmodified NPs, whereas NPs modified with a high Rt density (HRt-NPs) showed ≈0.8 folds change in uptake relative to unmodified NPs. Similarly, in vivo LRt-NPs showed higher accumulation in fibrotic livers in comparison to healthy livers whereas HRt-NPs and unmodified NPs showed lower accumulation in fibrotic livers relative to healthy controls respectively. Finally, the ability of drug-loaded NPs in preventing HSCs activation was assessed by monitoring the reduction in α-smooth muscle actin (α-SMA) expression by Western blot. NPs loaded with both JQ1 and atorvastatin showed reduction in α-SMA expression. In addition, a synergistic reduction in α-SMA was observed when cells were co-treated with JQ1 and atorvastatin loaded NPs.


Assuntos
Atorvastatina/administração & dosagem , Azepinas/administração & dosagem , Células Estreladas do Fígado/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Cirrose Hepática/tratamento farmacológico , Triazóis/administração & dosagem , Actinas/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Quitosana/química , Modelos Animais de Doenças , Portadores de Fármacos/química , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Células HEK293 , Células Estreladas do Fígado/imunologia , Humanos , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Masculino , Camundongos , Nanopartículas/química , Proteínas Nucleares/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Resultado do Tratamento , Vitamina A/química
5.
Pharm Dev Technol ; 18(5): 1078-88, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22656315

RESUMO

OBJECTIVE: The aim of this study was to investigate the effect of two mechanistically different porogens, namely: the hydrophilic hydroxy-propyl-ß-cyclodextrin and the hydrophobic porogens (mineral oil and corn oil) in producing open/closed pored engineered polylactide-co-glycolic-acid microspheres suitable for pulmonary delivery of risedronate sodium (RS). MATERIALS AND METHODS: Surface morphology of the microspheres was studied and they were characterized for entrapment efficiency (%EE), particle size, and porosity as well as aerodynamic and flow properties. Selected formulae were investigated for in vitro drug release and deposition behavior using next generation impactor. Furthermore, the safety of the free drug and the selected prepared systems was assessed by MTT viability test performed on Calu-3 cell line. RESULTS AND DISCUSSION: The current work revealed that HP-ß-CD produced open-pored microspheres, while oils produced closed pored microspheres. Modulation of preparation parameters generated porous RS microspheres with high %EE, sustained drug release profile up to 15 days, suitable geometric and aerodynamic particle sizes and excellent flow properties. The safety of HP-ß-CD systems was higher than the systems utilizing oil as porogen. CONCLUSION: Porogen type affected the behavior of the microspheres as demonstrated by the various characterization experiments, with microspheres prepared using HP-ß-CD being superior to those prepared using oils as porogens.


Assuntos
Ácido Etidrônico/análogos & derivados , Poliglactina 910/química , Linhagem Celular , Óleo de Milho/química , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microesferas , Óleo Mineral/química , Tamanho da Partícula , Poliglactina 910/administração & dosagem , Porosidade , Ácido Risedrônico , beta-Ciclodextrinas/administração & dosagem , beta-Ciclodextrinas/química
6.
AAPS PharmSciTech ; 9(1): 154-62, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18446476

RESUMO

The purpose of this study was to prepare lipospheres containing aceclofenac intended for topical skin delivery with the aim of exploiting the favorable properties of this carrier system and developing a sustained release formula to overcome the side effects resulting from aceclofenac oral administration. Lipospheres were prepared using different lipid cores and phospholipid coats adopting melt and solvent techniques. Characterization was carried out through photomicroscopy, scanning electron microscopy, particle size analysis, DSC, In vitro drug release and storage study. The anti-inflammatory effect of liposphere systems was assessed by the rat paw edema technique and compared to the marketed product. Results revealed that liposphere systems were able to entrap aceclofenac at very high levels (93.1%). The particle size of liposphere systems was well suited for topical drug delivery. DSC revealed the molecular dispersion of aceclofenac when incorporated in lipospheres. Both entrapment efficiency and release were affected by the technique of preparation, core and coat types, core to coat ratio and drug loading. Lipospheres were very stable after 3 months storage at 2-8 degrees C manifested by low leakage rate (less than 7%) and no major changes in particle size. Finally, liposphere systems were found to possess superior anti-inflammatory activity compared to the marketed product in both lotion and paste consistencies. Liposphere systems proved to be a promising topical system for the delivery of aceclofenac as they possessed the ability to entrap the drug at very high levels and high stability, and to sustain the anti-inflammatory effect of the drug.


Assuntos
Preparações de Ação Retardada/química , Diclofenaco/análogos & derivados , Composição de Medicamentos/métodos , Inflamação/prevenção & controle , Lipossomos/química , Administração Tópica , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Diclofenaco/administração & dosagem , Diclofenaco/química , Difusão , Avaliação Pré-Clínica de Medicamentos , Inflamação/patologia , Masculino , Teste de Materiais , Ratos
7.
AAPS PharmSciTech ; 8(1): 1, 2007 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-17408209

RESUMO

The purpose of this study was to formulate topically effective controlled release ophthalmic acetazolamide liposomal formulations. Reverse-phase evaporation and lipid film hydration methods were used for the preparation of reverse-phase evaporation (REVs) and multilamellar (MLVs) acetazolamide liposomes consisting of egg phosphatidylcholine (PC) and cholesterol (CH) in the molar ratios of (7:2), (7:4), (7:6), and (7:7) with or without stearylamine (SA) or dicetyl phosphate (DP) as positive and negative charge inducers, respectively. The prepared liposomes were evaluated for their entrapment efficiency and in vitro release. Multilamellar liposomes entrapped greater amounts of drug than REVs liposomes. Drug loading was increased by increasing CH content as well as by inclusion of SA. Drug release rate showed an order of negatively charged > neutral > positively charged liposomes, which is the reverse of the data of drug loading efficiency. Physical stability study indicated that approximately 89%, 77%, and 69% of acetazolamide was retained in positive, negative, and neutral MLVs liposomal formulations up to a period of 3 months at 4 degrees C. The intraocular pressure (IOP)-lowering activity of selected acetazolamide liposomal formulations was determined and compared with that of plain liposomes and acetazolamide solution. Multilamellar acetazolamide liposomes revealed more prolonged effect than REVs liposomes. The positively charged and neutral liposomes exhibited greater lowering in IOP and a more prolonged effect than the negatively charged ones. The positive multilamellar liposomes composed of PC:CH:SA (7:4:1) molar ratio showed the maximal response, which reached a value of -7.8 +/- 1.04 mmHg after 3 hours of topical administration.


Assuntos
Acetazolamida/administração & dosagem , Acetazolamida/química , Pressão Intraocular/efeitos dos fármacos , Lipossomos/química , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/química , Veículos Farmacêuticos/química , Administração Tópica , Animais , Difusão , Composição de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos , Pressão Intraocular/fisiologia , Masculino , Teste de Materiais , Tamanho da Partícula , Coelhos , Propriedades de Superfície
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