RESUMEN
Ralstonia solanacearum is among the most damaging bacterial phytopathogens with a wide number of hosts and a broad geographic distribution worldwide. The pathway of phenotype conversion (Phc) is operated by quorum-sensing signals and modulated through the (R)-methyl 3-hydroxypalmitate (3-OH PAME) in R. solanacearum. However, the molecular structures of the Phc pathway components are not yet established, and the structural consequences of 3-OH PAME on quorum sensing are not well studied. In this study, 3D structures of quorum-sensing proteins of the Phc pathway (PhcA and PhcR) were computationally modeled, followed by the virtual screening of the natural compounds library against the predicted active site residues of PhcA and PhcR proteins that could be employed in limiting signaling through 3-OH PAME. Two of the best scoring common ligands ZINC000014762512 and ZINC000011865192 for PhcA and PhcR were further analyzed utilizing orbital energies such as HOMO and LUMO, followed by molecular dynamics simulations of the complexes for 100 ns to determine the ligands binding stability. The findings indicate that ZINC000014762512 and ZINC000011865192 may be capable of inhibiting both PhcA and PhcR. We believe that, after further validation, these compounds may have the potential to disrupt bacterial quorum sensing and thus control this devastating phytopathogenic bacterial pathogen.
Asunto(s)
Ralstonia solanacearum , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Ligandos , Percepción de Quorum/genéticaRESUMEN
BACKGROUND: The plant growth is influenced by multiple interactions with biotic (microbial) and abiotic components in their surroundings. These microbial interactions have both positive and negative effects on plant. Plant growth promoting bacterial (PGPR) interaction could result in positive growth under normal as well as in stress conditions. METHODS: Here, we have screened two PGPR's and determined their potential in induction of specific gene in host plant to overcome the adverse effect of biotic stress caused by Magnaporthe grisea, a fungal pathogen that cause blast in rice. We demonstrated the glucanase protein mode of action by performing comparative modeling and molecular docking of guanosine triphosphate (GTP) ligand with the protein. Besides, molecular dynamic simulations have been performed to understand the behavior of the glucanase-GTP complex. RESULTS: The results clearly showed that selected PGPR was better able to induce modification in host plant at morphological, biochemical, physiological and molecular level by activating the expression of ß-1,3-glucanases gene in infected host plant. The docking results indicated that Tyr75, Arg256, Gly258, and Ser223 of glucanase formed four crucial hydrogen bonds with the GTP, while, only Val220 found to form hydrophobic contact with ligand. CONCLUSIONS: The PGPR able to induce ß-1,3-glucanases gene in host plant upon pathogenic interaction and ß-1,3-glucanases form complex with GTP by hydrophilic interaction for induction of defense cascade for acquiring resistance against Magnaporthe grisea.
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Magnaporthe , Oryza , Antifúngicos/metabolismo , Antifúngicos/farmacología , Bacterias , Guanosina Trifosfato/metabolismo , Guanosina Trifosfato/farmacología , Ligandos , Magnaporthe/metabolismo , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Oryza/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
Poly (lactidecoglycolide) (PLGA) nanoparticles (NPs) are biodegradable carriers that participate in the transport of neuroprotective drugs across the blood brain barrier (BBB). Targeted brainderived neurotrophic factor (BDNF) delivery across the BBB could provide neuroprotection in brain injury. We tested the neuroprotective effect of PLGA nanoparticlebound BDNF in a permanent middle cerebral artery occlusion (pMCAO) model of ischemia in rats. SpragueDawley rats were subjected to pMCAO. Four hours after pMCAO, two groups were intravenously treated with BDNF and NPBDNF, respectively. Functional outcome was assessed at 2 and 24 h after pMCAO, using the modified neurologic severity score (mNSS) and rotarod performance tests. Following functional assessments, rats were euthanized blood was taken to assess levels of the neurobiomarkers neuronspecific enolase and S100 calciumbinding protein ß (S100ß), and the brain was evaluated to measure the infarct volume. The NPBDNFtreated group showed significant improvement in mNSS compared with pMCAO and BDNFtreated groups and showed improved rotarod performance. The infarct volume in rats treated with NPBDNFs was also significantly smaller. These results were further corroborated by correlating differences in estimated NSE and S100ß. NPBDNFs exhibit a significant neuroprotective effect in the pMCAO model of ischemia in rats.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/uso terapéutico , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Nanopartículas/administración & dosificación , Fármacos Neuroprotectores/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/administración & dosificación , Animales , Factor Neurotrófico Derivado del Encéfalo/administración & dosificación , Factor Neurotrófico Derivado del Encéfalo/farmacología , Portadores de Fármacos , Infarto de la Arteria Cerebral Media/sangre , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/patología , Masculino , Fármacos Neuroprotectores/administración & dosificación , Paresia/etiología , Paresia/prevención & control , Fosfopiruvato Hidratasa/sangre , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Prueba de Desempeño de Rotación con Aceleración Constante , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Índice de Severidad de la EnfermedadRESUMEN
Analysis of protein-protein interactions is important for better understanding of molecular mechanisms involved in immune regulation and has potential for elaborating avenues for drug discovery targeting T-cell motility. Currently, only a small fraction of protein-protein interactions have been characterized in T-lymphocytes although there are several detection methods available. In this regard, computational approaches garner importance, with the continued explosion of genomic and proteomic data, for handling protein modeling and protein-protein interactions in large scale. Here, we describe a computational method to identify protein-protein interactions based on in silico protein design.
Asunto(s)
Movimiento Celular , Biología Computacional/métodos , Linfocitos T/metabolismo , Glucógeno Sintasa Quinasa 3 beta/química , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Receptor Notch1/química , Receptor Notch1/metabolismo , Linfocitos T/citologíaRESUMEN
Atopic dermatitis (AD) is a chronically relapsing eczematous skin disease characterised by frequent episodes of rashes, severe flares, and inflammation. Till date, there is no absolute therapy for the treatment of AD; however, topical corticosteroids (TCs) are the majorly prescribed class of drugs for the management of AD in both adults and children. Though, topical route is most preferable; however, limited penetration of therapeutics across the startum cornum (SC) is one of the major challenges for scientists. Therefore, the present study was attempted to fabricate a moderate-potency TC, betamethasone valerate (BMV), in the form of chitosan nanoparticles (CS-NPs) for optimum dermal targeting and improved penetration across the SC. To further improve the targeting efficiency of BMV and to potentiate its therapeutic efficacy, the fabricated BMV-CS-NPs were coated with hyaluronic acid (HA). The prepared NPs were characterised for particle size, zeta potential, polydispersity index (PDI), entrapment efficiency, loading capacity, crystallinity, thermal behaviour, morphology, in vitro release kinetics, drug permeation across the SC, and percentage of drug retained into various skin layers. Results showed that optimised HA-BMV-CS-NPs exhibited optimum physicochemical characteristics including finest particle size (< 300 ± 28 nm), higher zeta potential (+ 58 ± 8 mV), and high entrapment efficiency (86 ± 5.6%) and loading capacity (34 ± 7.2%). The in vitro release study revealed that HA-BMV-CS-NPs displayed Fickian diffusion-type mechanism of release in simulated skin surface (pH 5.5). Drug permeation efficiency of BMV was comparatively higher in case of BMV-CS-NPs; however, the amount of drug retained into the epidermis and the dermis was comparatively higher in case of HA-BMV-CS-NPs, compared to BMV-CS-NPs. Conclusively, we anticipate that HA-BMV-CS-NPs could be a promising nanodelivery system for efficient dermal targeting of BMV and improved anti-AD efficacy.
Asunto(s)
Valerato de Betametasona , Quitosano , Sistemas de Liberación de Medicamentos , Glucocorticoides , Ácido Hialurónico , Nanopartículas , Animales , Valerato de Betametasona/administración & dosificación , Valerato de Betametasona/química , Quitosano/administración & dosificación , Quitosano/química , Composición de Medicamentos , Liberación de Fármacos , Glucocorticoides/administración & dosificación , Glucocorticoides/química , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/química , Cinética , Nanopartículas/administración & dosificación , Nanopartículas/química , Ratas Wistar , Piel/metabolismo , Absorción CutáneaRESUMEN
Carbon nanotubes (CNTs) possess outstanding properties that could be useful in several technological, drug delivery, and diagnostic applications. However, their unique physical and chemical properties are hindered due to their poor solubility. This article review's the different ways and means of solubility enhancement of single-wall carbon nanotubes (SWNTs). The advantages of SWNTs over the multi-walled carbon nanotubes (MWNTs) and the method of non-covalent modification for solubility enhancement has been the key interest in this review. The review also highlights a few examples of dispersant design. The review includes some interesting utility of SWNTs being wrapped with polymer especially in biological media that could mediate proper drug delivery to target cells. Further, the use of wrapped SWNTs with phospholipids, nucleic acid, and amphiphillic polymers as biosensors is of research interest. The review aims at summarizing the developments relating to wrapped SWNTs to generate further research prospects in healthcare.
Asunto(s)
Nanotubos de Carbono , Polímeros , Animales , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Nanomedicina , Nanotubos de Carbono/química , Polímeros/administración & dosificación , Polímeros/química , SolubilidadRESUMEN
Trans-resveratrol was earlier shown to lower intraocular pressure (IOP) in rats; however, its mechanisms of action remain unclear. It has been shown to modulate adenosine receptor (AR) and TGF-ß2 signaling, both of which play a role in regulating IOP. Hence, we investigated effects of trans-resveratrol on AR and TGF-ß2 signaling. Steroid-induced ocular hypertensive (SIOH) rats were pretreated with A1AR, phospholipase C (PLC) and ERK1/2 inhibitors and were subsequently treated with single drop of trans-resveratrol. Metalloproteinases (MMP)-2 and -9 were measured in aqueous humor (AH). In another set of experiments, effect of trans-resveratrol on AH level of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA) was determined after single and multiple drop administration in SIOH rats. Effect of trans-resveratrol on ARs expression, PLC and pERK1/2 activation and MMPs, tPA and uPA secretion was determined using human trabecular meshwork cells (HTMC). Further, effect of trans-resveratrol on TGF-ß2 receptors, SMAD signaling molecules and uPA and tPA expression by HTMC was determined in the presence and absence of TGF-ß2. Pretreatment with A1AR, PLC and ERK1/2 inhibitors antagonized the IOP lowering effect of trans-resveratrol and caused significant reduction in the AH level of MMP-2 in SIOH rats. Trans-resveratrol increased A1AR and A2AAR expression, cellular PLC, pERK1/2 levels and MMP-2, tPA and uPA secretion by HTMC. Additionally, it produced TGFßRI downregulation and SMAD 7 upregulation. In conclusion, IOP lowering effect of trans-resveratrol involves upregulation of A1AR expression, PLC and ERK1/2 activation and increased MMP-2 secretion. It downregulates TGFßRI and upregulates SMAD7 hence, inhibits TGF-ß2 signaling.
Asunto(s)
Presión Intraocular/efectos de los fármacos , Hipertensión Ocular/tratamiento farmacológico , Resveratrol/farmacología , Transducción de Señal/efectos de los fármacos , Antagonistas del Receptor de Adenosina A1/farmacología , Administración Oftálmica , Animales , Células Cultivadas , Dexametasona/farmacología , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , Masculino , Hipertensión Ocular/inducido químicamente , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Receptores Purinérgicos P1/metabolismo , Resveratrol/uso terapéutico , Malla Trabecular/citología , Malla Trabecular/efectos de los fármacos , Factor de Crecimiento Transformador beta2/metabolismo , Resultado del Tratamiento , Fosfolipasas de Tipo C/antagonistas & inhibidores , Fosfolipasas de Tipo C/metabolismo , Regulación hacia Arriba/efectos de los fármacosRESUMEN
BACKGROUND: Categorized as a Biopharmaceutics Classification System (BCS) Class II drugs, statin exhibit low aqueous solubility and bioavailability thus presenting an obstacle and great challenge to formulation researchers. This paper describes a de novo approach to enhance the aqueous solubility of one of the most commonly prescribed statins i.e., simvastatin (SMV) by forming a complex (SMV-ARG) with cosolute arginine (ARG). METHODS: The complex has been characterized for its apparent solubility and in vitro dissolution. The solid state characterization has been carried out using Fourier Transform Infra-Red (FTIR) Spectroscopy, Elemental Analysis, X-Ray Powder Diffraction (XRD), Differential Scanning Calorimetry (DSC) analysis, Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). RESULTS: Simvastatin-Arginine (SMV-ARG) complex exhibited massive solubility enhancement by 12,000 fold and significant improvement in both acidic and alkaline dissolution media. A conversion of coherent crystalline to non-coherent pattern, and certain extent of amorphization in SMV-ARG complex, fully justifies the enhanced solubility, and hence the dissolution profile. CONCLUSION: The present study provides a significant evidence that ARG molecules are capable to form a complex with small molecules and increase their aqueous solubility which prove to be beneficial in drug formulation and development.
Asunto(s)
Arginina/química , Simvastatina/química , Rastreo Diferencial de Calorimetría , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Difracción de Polvo , Solubilidad , Temperatura , Agua/químicaRESUMEN
Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels.
Asunto(s)
Catarata/prevención & control , Diabetes Mellitus Experimental/complicaciones , Cristalino/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Tocotrienoles/farmacología , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Administración Tópica , Animales , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Calpaína , Catalasa/metabolismo , Catarata/complicaciones , Diabetes Mellitus Experimental/sangre , Expresión Génica/efectos de los fármacos , Glutatión/metabolismo , Cristalino/metabolismo , Cristalino/patología , Masculino , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Nitrosación/efectos de los fármacos , Proyectos Piloto , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo , Factores de Tiempo , Tocotrienoles/administración & dosificaciónRESUMEN
Atopic dermatitis (AD) is a chronically relapsing skin inflammatory disorder characterized by perivascular infiltration of immunoglobulin-E (IgE), T-lymphocytes and mast cells. The key pathophysiological factors causing this disease are immunological disorders and the compromised epidermal barrier integrity. Pruritus, intense itching, psychological stress, deprived physical and mental performance and sleep disturbance are the hallmark features of this dermatological complication. Preventive interventions which include educational programs, avoidance of allergens, exclusive care towards skin, and the rational selection of therapeutic regimen play key roles in the treatment of dermatosis. In last two decades, it is evident from a plethora of studies that scientific focus is being driven from conventional therapies to the advanced nanocarrier-based regimen for an effective management of AD. These nanocarriers which include polymeric nanoparticles (NPs), hydrogel NPs, liposomes, ethosomes, solid lipid nanoparticles (SLNs) and nanoemulsion, provide efficient roles for the target specific delivery of the therapeutic payload. The success of these targeted therapies is due to their pharmaceutical versatility, longer retention time at the target site, avoiding off-target effects and preventing premature degradation of the incorporated drugs. The present review was therefore aimed to summarise convincing evidence for the therapeutic superiority of advanced nanocarrier-mediated strategies over the conventional therapies used in the treatment of AD.
Asunto(s)
Dermatitis Atópica/tratamiento farmacológico , Portadores de Fármacos/administración & dosificación , Sistemas de Liberación de Medicamentos , Nanomedicina/tendencias , Manejo de la Enfermedad , Portadores de Fármacos/química , HumanosRESUMEN
Categorized as a Biopharmaceutics Classification System Class II drugs, atorvastatin (ATV) exhibits low aqueous solubility and bioavailability thus presenting an obstacle and great challenge to formulation researchers. Numerous studies are available in regard to the solubility enhancement of ATV, but very few actually describe this phenomenon in terms of thermodynamics and the solute-solvent interaction. Arginine (ARG) is an amino acid that has been reported to enhance the solubility of the highly insoluble wheat protein gluten through hydrogen bonding and π electron-cation interaction. To our knowledge, ARG has never been investigated as a solubility enhancement agent of aqueous insoluble drugs. Thus, this study aimed to elucidate the solute-solvent and solute-cosolute interactions and derive thermodynamic parameters that bolstered the solubility of ATV in the presence of ARG. We examined the electrolytic conductance and densities of ATV-ARG binary system covering the temperature ranging from 298.15 K to 313.15 K. Conductometric and volumetric parameters such as limiting molar conductance, association constants, limiting partial molar volumes, and expansibility values were calculated. Additionally, thermodynamic parameters (ΔG(0), ΔH(0), ΔS(0), and Es) involved in the association process of the solute in the aqueous solution of ARG were also determined.
RESUMEN
The inhibitory role of AgNO3 on glucose-mediated respiration in Escherichia coli has been investigated as a function of pH and temperature using Clark-type electrode, environmental scanning electron microscopy, and computational tools. In the given concentration of bacterial suspension (1 × 108 CFU/ml), E. coli showed an increasing nonlinear trend of tetra-phasic respiration between 1-133 µM glucose concentration within 20 min. The glucose concentrations above 133 µM did not result any linear increment in respiration but rather showed a partial inhibition at higher glucose concentrations (266-1066 µM). In the presence of glucose, AgNO3 caused a concentration-dependent (47-1960 µM) inhibition of the respiration rate within 4 min of its addition. The respiration rate was the highest at pH 7-8 and then was decreased on either side of this pH range. The inhibitory action of AgNO3 upon bacterial respiration was the highest at 37 °C. The observations of the respiration data were well supported by the altered bacterial morphology as observed in electron microscopic study. Docking study indicated the AgNO3 binding to different amino acids of all respiratory complex enzymes in E. coli and thereby explaining its interference with the respiratory chain. Copyright © 2016 John Wiley & Sons, Ltd.
Asunto(s)
Transporte de Electrón/efectos de los fármacos , Escherichia coli/fisiología , Glucosa/metabolismo , Nitrato de Plata/farmacología , Sitios de Unión , Escherichia coli/efectos de los fármacos , Escherichia coli/ultraestructura , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Simulación del Acoplamiento Molecular , TemperaturaRESUMEN
We examined the solubility of simvastatin in water in 0.01 mol·dm(-3), 0.02 mol·dm(-3), 0.04 mol·dm(-3), 0.09 mol·dm(-3), 0.18 mol·dm(-3), 0.36 mol·dm(-3), and 0.73 mol·dm(-3) arginine (ARG) solutions. The investigated drug is termed the solute, whereas ARG the cosolute. Phase solubility studies illustrated a higher extent of solubility enhancement for simvastatin. The aforementioned system was subjected to conductometric and volumetric measurements at temperatures (T) of 298.15 K, 303.15 K, 308.15 K, and 313.15 K to illustrate the thermodynamics involved and related solute-solvent interactions. The conductance values were used to evaluate the limiting molar conductance and association constants. Thermodynamic parameters (ΔG (0), ΔH (0), ΔS (0), and E s) for the association process of the solute in the aqueous solutions of ARG were calculated. Limiting partial molar volumes and expansibilities were evaluated from the density values. These values are discussed in terms of the solute-solvent and solute-cosolute interactions. Further, these systems were analyzed using ultraviolet-visible analysis, Fourier-transform infrared spectroscopy, and (13)C, (1)H, and two-dimensional nuclear overhauser effect spectroscopy nuclear magnetic resonance to complement thermophysical explanation.
Asunto(s)
Arginina/química , Simvastatina/química , Solventes/química , Espectroscopía de Resonancia Magnética , Conformación Molecular , Solubilidad , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua/químicaRESUMEN
Steroid-induced hypertension and glaucoma is associated with increased extracellular meshwork (ECM) deposition in trabecular meshwork (TM). Previous studies have shown that single drop application of trans-resveratrol lowers IOP in steroid-induced ocular hypertensive (SIOH) rats. This IOP lowering is attributed to activation of adenosine A1 receptors, which may lead to increased matrix metalloproteinase (MMP)-2 activity. This study evaluated the effect of repeated topical application of trans-resveratrol for 21 days in SIOH animals on IOP, changes in MMP-2 level in aqueous humor, trabecular meshwork and retinal morphology and retinal redox status. We observed that treatment with trans-resveratrol results in significant and sustained IOP reduction in SIOH rats. This IOP reduction is associated with significantly higher aqueous humor total MMP-2 level; significantly reduced TM thickness and increased number of TM cells. Treatment with trans-resveratrol also significantly increased ganglion cell layer (GCL) thickness, the linear cell density in the GCL and inner retina thickness; and significantly reduced retinal oxidative stress compared to the SIOH vehicle-treated group. In conclusion, repeated dose topical application of trans-resveratrol produces sustained IOP lowering effect, which is associated with increased level of aqueous humor MMP-2, normalization of TM and retinal morphology and restoration of retinal redox status.
Asunto(s)
Antioxidantes/administración & dosificación , Modelos Animales de Enfermedad , Presión Intraocular/efectos de los fármacos , Hipertensión Ocular/tratamiento farmacológico , Retina/patología , Estilbenos/administración & dosificación , Malla Trabecular/patología , Administración Tópica , Animales , Humor Acuoso/enzimología , Recuento de Células , Femenino , Glucocorticoides/toxicidad , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Hipertensión Ocular/inducido químicamente , Hipertensión Ocular/enzimología , Hipertensión Ocular/patología , Soluciones Oftálmicas , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Resveratrol , Células Ganglionares de la Retina/efectos de los fármacos , Tonometría OcularRESUMEN
Despite the fact that intrinsic oxidative stress is inevitable, the extrinsic factor such as ultraviolet radiation enhances reactive oxygen species (ROS) generation resulting in premature skin aging. Nanoemulsion was loaded with fullerene, a strong free radical scavenger, and its efficacy to provide protection and regenerative effect against ROS-induced collagen breakdown in human skin was studied. Stable fullerene nanoemulsions were formulated using high shear homogenization and ultrasonic dispersion technique. An open trial was conducted using fullerene nanoemulsion on skin twice a day for 28 days. The mean collagen score significantly increased (P<0.05) from 36.53±4.39 to 48.69±5.46 with 33.29% increment at the end of the treatment. Biophysical characteristics of skin revealed that skin hydration was increased significantly (P<0.05) from 40.91±7.01 to 58.55±6.08 corneometric units (43.12% increment) and the water was able to contain within the stratum corneum without any increased in transepidermal water loss. In the in vitro safety evaluation, fullerene nanoemulsion showed no acute toxicity on 3T3 fibroblast cell line for 48h and no indication of potential dermal irritation. Hence, the fullerene nanoemulsion may assist in protecting collagen from breakdown with cosmeceutical benefit.
Asunto(s)
Colágeno/fisiología , Fulerenos/administración & dosificación , Nanopartículas/administración & dosificación , Regeneración/efectos de los fármacos , Envejecimiento de la Piel/efectos de los fármacos , Células 3T3 , Adulto , Animales , Antioxidantes/administración & dosificación , Antioxidantes/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Colágeno/química , Emulsiones , Femenino , Depuradores de Radicales Libres/metabolismo , Fulerenos/metabolismo , Humanos , Masculino , Ratones , Nanopartículas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Regeneración/fisiología , Envejecimiento de la Piel/fisiología , Cuidados de la Piel/métodosRESUMEN
BACKGROUND: Steroid-induced ocular hypertension is currently treated in the same way as primary open-angle glaucoma. However, the treatment is often suboptimal and is associated with adverse effects. We evaluated the oculohypotensive effects of topical trans-resveratrol in rats with steroid-induced ocular hypertension and involvement of adenosine receptors (AR) in intraocular pressure (IOP) lowering effect of trans-resveratrol. METHODS: The oculohypotensive effect of unilateral single-drop application of various concentrations of trans-resveratrol was first studied in oculonormotensive rats. Concentration with maximum effect was similarly studied in rats with steroid-induced ocular hypertension. Involvement of AR was studied by observing the alterations of IOP in response to trans-resveratrol after pretreating animals with AR subtype-specific antagonists. Additionally, we used computational methods, including 3D modelling, 3D structure generation and protein-ligand interaction, to determine the AR-trans-resveratrol interaction. RESULTS: All concentrations of trans-resveratrol produced significant IOP reduction in normotensive rat eyes. Maximum mean IOP reduction of 15.1% was achieved with trans-resveratrol 0.2%. In oculohypertensive rats, trans-resveratrol 0.2% produced peak IOP reduction of 25.2%. Pretreatment with A1 antagonist abolished the oculohypotensive effect of trans-resveratrol. Pretreatment with A3 and A2A AR antagonists produced significant IOP reduction in both treated and control eyes, which was further augmented by trans-resveratrol application in treated eyes. Computational studies showed that trans-resveratrol has highest affinity for A2B and A1, followed by A2A and A3 AR. CONCLUSION: Topically applied trans-resveratrol reduces IOP in rats with steroid-induced ocular hypertension. Trans-resveratrol-induced oculohypotension involves its agonistic activity at the A1 AR.
Asunto(s)
Antihipertensivos/administración & dosificación , Antioxidantes/administración & dosificación , Presión Intraocular/efectos de los fármacos , Hipertensión Ocular/tratamiento farmacológico , Receptores Purinérgicos P1/fisiología , Estilbenos/administración & dosificación , Administración Tópica , Animales , Dexametasona/toxicidad , Modelos Animales de Enfermedad , Femenino , Glucocorticoides/toxicidad , Masculino , Hipertensión Ocular/inducido químicamente , Hipertensión Ocular/metabolismo , Soluciones Oftálmicas , Antagonistas de Receptores Purinérgicos P1/farmacología , Ratas , Ratas Sprague-Dawley , Resveratrol , Tonometría OcularRESUMEN
This research aims to formulate and to optimize a nanoemulsion-based formulation containing fullerene, an antioxidant, stabilized by a low amount of mixed surfactants using high shear and the ultrasonic emulsification method for transdermal delivery. Process parameters optimization of fullerene nanoemulsions was done by employing response surface methodology, which involved statistical multivariate analysis. Optimization of independent variables was investigated using experimental design based on Box-Behnken design and central composite rotatable design. An investigation on the effect of the homogenization rate (4,000-5,000 rpm), sonication amplitude (20%-60%), and sonication time (30-150 seconds) on the particle size, ζ-potential, and viscosity of the colloidal systems was conducted. Under the optimum conditions, the central composite rotatable design model suggested the response variables for particle size, ζ-potential, and viscosity of the fullerene nanoemulsion were 152.5 nm, -52.6 mV, and 44.6 pascal seconds, respectively. In contrast, the Box-Behnken design model proposed that preparation under the optimum condition would produce nanoemulsion with particle size, ζ-potential, and viscosity of 148.5 nm, -55.2 mV, and 39.9 pascal seconds, respectively. The suggested process parameters to obtain optimum formulation by both models yielded actual response values similar to the predicted values with residual standard error of <2%. The optimum formulation showed more elastic and solid-like characteristics due to the existence of a large linear viscoelastic region.
Asunto(s)
Fulerenos/química , Nanoestructuras/química , Administración Cutánea , Química Farmacéutica , Elasticidad , Emulsiones/administración & dosificación , Emulsiones/química , Fulerenos/administración & dosificación , Modelos Químicos , Nanoestructuras/administración & dosificación , Tamaño de la Partícula , Proyectos de Investigación , Reología , ViscosidadRESUMEN
Fullerene nanoemulsions were formulated in palm kernel oil esters stabilized by low amount of mixed nonionic surfactants. Pseudoternary phase diagrams were established in the colloidal system of PKOEs/Tween 80 : Span 80/water incorporated with fullerene as antioxidant. Preformulation was subjected to combination of high and low energy emulsification methods and the physicochemical characteristics of fullerene nanoemulsions were analyzed using electroacoustic spectrometer. Oil-in-water (O/W) nanoemulsions with particle sizes in the range of 70-160 nm were formed. The rheological characteristics of colloidal systems exhibited shear thinning behavior which fitted well into the power law model. The effect of xanthan gum (0.2-1.0%, w/w) and beeswax (1-3%, w/w) in the estimation of thermodynamics was further studied. From the energetic parameters calculated for the viscous flow, a moderate energy barrier for transport process was observed. Thermodynamic study showed that the enthalpy was positive in all xanthan gum and beeswax concentrations indicating that the formation of nanoemulsions could be endothermic in nature. Fullerene nanoemulsions with 0.6% or higher xanthan gum content were found to be stable against creaming and flocculation when exposed to extreme environmental conditions.
Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Fulerenos/química , Absorción Cutánea/fisiología , Emulsiones/química , Fulerenos/administración & dosificación , Humanos , Aceite de Palma , Tamaño de la Partícula , Aceites de Plantas , Reología , TermodinámicaRESUMEN
PURPOSE: Oxidative and nitrosative stress underlies cataractogenesis, and therefore, various antioxidants have been investigated for anticataract properties. Several vitamin E analogs have also been studied for anticataract effects due to their antioxidant properties; however, the anticataract properties of tocotrienols have not been investigated. In this study, we investigated the effects of topically applied tocotrienol on the onset and progression of cataract and lenticular oxidative and nitrosative stress in galactosemic rats. METHODS: In the first part of this study, we investigated the effects of topically applied microemulsion formulation of tocotrienol (TTE) using six concentrations ranging from 0.01% to 0.2%. Eight groups of Sprague-Dawley rats (n = 9) received distilled water, vehicle, or one of the six TTE concentrations as pretreatment topically twice daily for 3 weeks while on a normal diet. After pretreatment, animals in groups 2-8 received a 25% galactose diet whereas group 1 continued on the normal diet for 4 weeks. During this 4-week period, topical treatment continued as for pretreatment. Weekly slit-lamp examination was conducted to assess cataract progression. At the end of the experimental period, the animals were euthanized, and the proteins and oxidative stress parameters were estimated in the lenses. In the second part of the study, we compared the anticataract efficacy of the TTE with the liposomal formulation of tocotrienol (TTL) using five groups of Sprague-Dawley rats (n = 15) that received distilled water, TTE, TTL, or corresponding vehicle. The mode of administration and dosing schedule were the same as in study 1. Weekly ophthalmic examination and lens protein and oxidative stress estimates were performed as in study 1. Lens nitrosative stress was also estimated. RESULTS: During the 4-week treatment period, the groups treated with 0.03% and 0.02% tocotrienol showed slower progression of cataract compared to the vehicle-treated group (p<0.05), whereas the group treated with 0.2% tocotrienol showed faster progression of cataract compared to the vehicle-treated group (p<0.05). The lenticular protein content, malondialdehyde, superoxide dismutase, and catalase levels were normalized in the groups that received 0.03% and 0.02% tocotrienol. The lenticular reduced glutathione also showed a trend toward normalization in these groups. In contrast, the group treated with 0.2% tocotrienol showed increased lenticular oxidative stress. When the microemulsion and liposomal formulations were compared, the effects on cataract progression, lens oxidative and nitrosative stress, and lens protein content did not show significant differences. CONCLUSIONS: Topically applied tocotrienol within the concentration range of less than 0.05% and more than 0.01% tends to delay the onset and progression of cataract in galactose-fed rats by reducing lenticular oxidative and nitrosative stress. However, topical tocotrienol at a concentration of 0.2% and higher aggravates cataractogenesis in galactose-fed rats by increasing lens oxidative stress. The anticataract efficacy of 0.03% microemulsion of tocotrienol did not differ from its liposomal formulations at the same concentration.
Asunto(s)
Catarata/complicaciones , Catarata/tratamiento farmacológico , Galactosemias/complicaciones , Cristalino/metabolismo , Cristalino/patología , Tocotrienoles/administración & dosificación , Tocotrienoles/uso terapéutico , Administración Tópica , Animales , Segmento Anterior del Ojo/efectos de los fármacos , Segmento Anterior del Ojo/patología , Catalasa/metabolismo , Catarata/metabolismo , Progresión de la Enfermedad , Emulsiones , Proteínas del Ojo/metabolismo , Galactosemias/metabolismo , Glutatión/metabolismo , Cristalino/efectos de los fármacos , Cristalino/enzimología , Liposomas/química , Malondialdehído/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Oxidación-Reducción/efectos de los fármacos , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Electricidad Estática , Estrés Fisiológico/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Tocotrienoles/farmacología , Tirosina/análogos & derivados , Tirosina/metabolismo , ViscosidadRESUMEN
This study presents development and evaluation of novel sustained release system of diclofenac sodium (DS) prepared by solid dispersion (SD) technique using Eudragit E 100 (EE 100) and/or Eudragit S 100 (ES 100) as carriers. Compatibility of the drug and its crystalline nature in the SD were examined using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The drug was relatively stable, amorphous in the SD. The greater amount of EE100 or ES 100 in the SD slowed down the release rates with smaller dissolution efficiency and hence the mean dissolution time was enhanced. Moreover, combined carriers of EE 100-ES 100 exhibited more dissolution retarding effect than any of the carriers. The release of drug followed anomalous transport in artificial intestinal juice (pH 6.8).