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1.
Int J Biol Macromol ; 269(Pt 1): 132122, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718992

RESUMEN

In the treatment of bowel diseases such as ulcerative colitis through oral administration, an effective drug delivery system targeting the colon is crucial for enhancing efficacy and minimizing side effects of therapeutic agents. This study focuses on the development of a novel nanocomposite hydrogel bead comprising a synergistic blend of biological macromolecules, namely sodium alginate (ALG) and hyaluronic acid (HA), reinforced with layered double hydroxide nanoparticles (LDHs) for the oral delivery of dual therapeutics. The synthesized hydrogel bead exhibits significantly enhanced gel strength and controllable release of methylprednisolone (MP) and curcumin (CUR), serving as an anti-inflammatory drug and a mucosal healing agent, compared to native ALG or ALG/HA hydrogel beads without LDHs. The physicochemical properties of the synthesized LDHs and hydrogel beads were characterized using various techniques, including scanning electron microscopy, zeta potential measurement, transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. In vitro release studies of MP and CUR under simulated gastrointestinal tract (GIT) conditions demonstrate the superior controlled release property of the nanocomposite hydrogel bead, particularly in minimizing premature drug release in the upper GIT environment while sustaining release of over 82 % of drugs in the colonic environment. Thus, the modularly engineered carrier designed for oral colon targeting holds promise as a potential candidate for the treatment of ulcerative colitis.


Asunto(s)
Alginatos , Liberación de Fármacos , Ácido Hialurónico , Hidrogeles , Nanopartículas , Alginatos/química , Ácido Hialurónico/química , Hidrogeles/química , Nanopartículas/química , Administración Oral , Portadores de Fármacos/química , Humanos , Hidróxidos/química , Curcumina/química , Curcumina/administración & dosificación , Curcumina/farmacología , Metilprednisolona/química , Metilprednisolona/administración & dosificación , Sistemas de Liberación de Medicamentos , Colitis Ulcerosa/tratamiento farmacológico
2.
J Biotechnol ; 314-315: 14-24, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32246945

RESUMEN

Synthetic glucocorticoids are generally preferred over their natural counterparts as these compounds exhibit improved anti-inflammatory potency and glucocorticoid receptor selectivity. However, the biotechnological production of these molecules is often subject to limitations inferred by restricted enzyme stability, selectivity or inhibition thereof. The latter is particularly important during 6α-methylprednisolone production, as the essential C21-hydroxylation of its precursor medrane appears to be hampered by product inhibition of the steroid-21-hydroxylase (CYP21A2). To circumvent this bottleneck, we established a two-step reaction for controlled mixed-culture fermentation, using recombinant E. coli. This process comprises the previously reported C21-hydroxylation of medrane by CYP21A2, followed by an instant derivatization of the hydroxylated product premedrol by chloramphenicol acetyl transferase 1 (CAT1). The CAT1-mediated C21-acetylation prevents the product from regaining access to the enzyme's active site which effectively shifts the chemical equilibrium toward premedrol formation. The successful circumvention of product inhibition at optimized conditions resulted in the formation of more than 1.5 g of product per liter which corresponds to an increase by more than 100 %. Taken together, we demonstrate an efficient system to enhance cytochrome P450-mediated biotransformations, holding great ecologic and economic potential to be applied in industrial processes.


Asunto(s)
Escherichia coli/metabolismo , Glucocorticoides/metabolismo , Acetilación , Biotransformación , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Técnicas de Cocultivo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentación , Glucocorticoides/química , Hidroxilación , Ingeniería Metabólica , Metilprednisolona/química , Metilprednisolona/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Esteroide 21-Hidroxilasa/genética , Esteroide 21-Hidroxilasa/metabolismo , Especificidad por Sustrato
3.
Int J Mol Sci ; 21(6)2020 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-32168938

RESUMEN

Methylprednisolone (MP) is often used in the treatment of various kidney diseases, but overcoming the systemic side effects caused by its nonspecific distribution in the body is a challenge. This article reports the design, synthesis, and renal targeting of methylprednisolone-lysozyme (MPS-LZM). This conjugate was obtained by covalently linking MP with the renal targeting carrier LZM through a linker containing an ester bond, which could utilize the renal targeting of LZM to deliver MP to renal proximal tubular epithelial cells and effectively release MP. The reaction conditions for the preparation of the conjugate were mild, and the quality was controllable. The number of drug payloads per LZM was 1.1. Cell-level studies have demonstrated the safety and endocytosis of the conjugate. Further pharmacokinetic experiments confirmed that, compared with that of free MP, the conjugate increased the renal exposure (AUC0-t) of active MP from 17.59 to 242.18 h*ng/mL, and the targeting efficiency improved by approximately 14 times. Tissue and organ imaging further revealed that the conjugate could reach the kidneys quickly, and fluorescence could be detected in the kidneys for up to 12 h. This study preliminarily validates the feasibility of a renal targeting design strategy for MPS-LZM, which is expected to provide a new option for improving kidney-specific distribution of glucocorticoids.


Asunto(s)
Riñón/citología , Metilprednisolona/administración & dosificación , Muramidasa/química , Animales , Células Cultivadas , Diseño de Fármacos , Humanos , Riñón/química , Masculino , Metilprednisolona/química , Metilprednisolona/farmacocinética , Ratones , Especificidad de Órganos
4.
Biotechnol Bioeng ; 117(4): 901-911, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31814109

RESUMEN

Synthetic glucocorticoids such as methylprednisolone are compounds of fundamental interest to the pharmaceutical industry as their modifications within the sterane scaffold lead to higher inflammatory potency and reduced side effects compared with their parent compound cortisol. In methylprednisolone production, the complex chemical hydroxylation of its precursor medrane in position C21 exhibits poor stereo- and regioselectivity making the process unprofitable and unsustainable. By contrast, the use of a recombinant E. coli system has recently shown high suitability and efficiency. In this study, we aim to overcome limitations in this biotechnological medrane conversion yielding the essential methylprednisolone-precursor premedrol by optimizing the CYP21A2-based whole-cell system on a laboratory scale. We successfully improved the whole-cell process in terms of premedrol production by (a) improving the electron supply to CYP21A2; here we use the N-terminally truncated version of the bovine NADPH-dependent cytochrome P450 reductase (bCPR-27 ) and coexpression of microsomal cytochrome b5 ; (b) enhancing substrate access to the heme by modification of the CYP21A2 substrate access channel; and (c) circumventing substrate inhibition which is presumed to be the main limiting factor of the presented system by developing an improved fed-batch protocol. By overcoming the presented limitations in whole-cell biotransformation, we were able to achieve a more than 100% improvement over the next best system under equal conditions resulting in 691 mg·L-1 ·d-1 premedrol.


Asunto(s)
Escherichia coli/genética , Ingeniería Metabólica/métodos , Metilprednisolona , Proteínas Recombinantes/metabolismo , Esteroide 21-Hidroxilasa/metabolismo , Animales , Biotransformación , Bovinos , Escherichia coli/metabolismo , Hidroxilación , Metilprednisolona/análogos & derivados , Metilprednisolona/análisis , Metilprednisolona/química , Metilprednisolona/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Esteroide 21-Hidroxilasa/química , Esteroide 21-Hidroxilasa/genética
5.
J Appl Biomater Funct Mater ; 18: 2280800020978505, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33535875

RESUMEN

Methylprednisolone sodium phosphate (MP) is an anti-inflammatory corticosteroid which is used in the treatment of spinal cord injury (SCI), however the overdose of MP has toxic effects Therefore it is prerequisite to develop novel approaches to overcome the side effects of MP and enhance its efficacy. In the present work, we have developed alkaline phosphatase (ALP) trigger self-assembly system of oligopeptides to physically entrap and locally deliver MP. The synthesis of Nap-Phe-Phe-Tyr(H2PO3)-OH (1P) was achieved using solid phase peptide synthesis and was characterized using mass spectroscopy. The 1P is a hydrogelator, which in presence of ALP self-assembles to form the hydrogel. During the self-assembly of 1P, MP was physically entrapped without losing the physical strength of hydrogel as revealed in the rheology study. The consistency of this hydrogel and the structure was characterized using circular dichroism. The MP was released from the hydrogel in a sustain manner and 80% of the drug release was observed at 120 h. The MP + 1P were non-toxic to the cells at lower concentration however toxicity increases with the increase in concentration of MP. Further, the in-vivo administration of MP + 1P significantly reduces the pro-inflammatory cytokines and the histological analysis revealed improvement in the SCI. In conclusion, it could be stated that the synthesis of 1P for the delivery of MP provides the novel opportunity in for the treatment of SCI.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Antiinflamatorios/metabolismo , Hidrogeles/química , Metilprednisolona/metabolismo , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Portadores de Fármacos/química , Liberación de Fármacos , Módulo de Elasticidad , Hidrogeles/metabolismo , Masculino , Metilprednisolona/química , Metilprednisolona/farmacología , Metilprednisolona/uso terapéutico , Microglía/citología , Microglía/metabolismo , Oligopéptidos/química , Oligopéptidos/metabolismo , Ratas , Ratas Sprague-Dawley , Reología , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/patología
6.
Anaesthesia ; 74(12): 1551-1557, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31228255

RESUMEN

Particulate corticosteroids have been described to lead to greater pain improvement compared with their non-particulate counterparts when used in epidural injections. It is hypothesised that filtering may significantly impact their concentration and long-term efficacy. We investigated if passing particulate suspensions through different commonly-used filters affects drug dosage. Two particulate corticosteroid formulations, triamcinolone acetonide and methylprednisolone acetate, were mixed at different concentrations with either bupivacaine hydrochloride or 0.9% sodium chloride. Solutions were passed through a 5-µm and a 0.2-µm filter. Mass spectroscopy results indicated a complete loss of corticosteroid from the solutions using both filters, and light microscopy imaging demonstrated agglomerate formation, suggesting that filtering interferes with drug dosage. The choice of diluents must also be considered to reduce large agglomerate formation. Clinicians should be aware of the consequences of filtering particulate suspensions and carefully consider the selection of diluent when considering treatment plans.


Asunto(s)
Corticoesteroides/administración & dosificación , Corticoesteroides/química , Química Farmacéutica , Composición de Medicamentos , Filtración , Técnicas de Dilución del Indicador , Inyecciones Epidurales , Metilprednisolona/administración & dosificación , Metilprednisolona/química , Tamaño de la Partícula , Material Particulado , Suspensiones , Triamcinolona Acetonida/administración & dosificación , Triamcinolona Acetonida/química
7.
Equine Vet J ; 51(3): 343-348, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30080939

RESUMEN

BACKGROUND: Methylprednisolone (MP) acetate is a commonly used corticosteroid for suppression of inflammation in synovial structures in horses. Its use is often regulated in equine sports by plasma MP concentrations. OBJECTIVES: To describe variability in MP plasma concentrations after MP acetate injection in different synovial structures and with co-administration with hyaluronic acid (HA). STUDY DESIGN: Field study in actively racing horses in three disciplines (Thoroughbred, Standardbred and Quarter Horse). METHODS: Seventy-six horses (15 Thoroughbreds, 20 Standardbreds and 41 Quarter Horses) were included in the study. Injection of any synovial structure with a total body dose of 100 mg MP acetate was permitted, data were grouped according to the synovial structure injected and co-administration with HA. Plasma was collected before injection and at 6 days post-injection. Per cent censored data (below the limit of quantification) for each synovial structure were determined, and summary statistics generated by Robust Regression on Order. Differences between synovial structures and co-administration with HA were identified by ANOVA with Tukey's post hoc testing. RESULTS: The MP plasma concentration at 6 days for injection for the entire group (mean ± standard deviation [s.d.], pg/mL) was 96 ± 104. Metacarpophalangeal (MCP) plasma concentrations contained 86% censored data and could not be included in the statistical analysis. The carpal joints (CJO) group had a lower plasma MP concentration (P<0.05) than the distal tarsal joints (DTJ) or medial femorotibial (MFT), the no HA (NHA) group had a lower plasma MP concentration (P<0.05) than HA. MAIN LIMITATIONS: The synovial structures injected varied by racing discipline, so this study was unable to identify any differences between disciplines. CONCLUSIONS: Practitioners should be aware that injection of DTJ, CS and MFT joints, and combining MP acetate with HA may prolong its clearance, and withdrawal times for competition in regulated equine sports.


Asunto(s)
Antiinflamatorios/farmacocinética , Enfermedades de los Caballos/tratamiento farmacológico , Inflamación/veterinaria , Articulaciones/lesiones , Metilprednisolona/farmacocinética , Líquido Sinovial/química , Animales , Antiinflamatorios/sangre , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Caballos , Inflamación/tratamiento farmacológico , Inyecciones Intraarticulares/veterinaria , Metilprednisolona/sangre , Metilprednisolona/química , Metilprednisolona/uso terapéutico
8.
Br J Clin Pharmacol ; 84(5): 1020-1028, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29385232

RESUMEN

AIMS: Intravenous high-dose free methylprednisolone (MP) hemisuccinate is the primary treatment for an acute relapse in relapsing-remitting multiple sclerosis. However, it is inconvenient and its side effects are undesirable. Both dose and dosing frequency can be reduced by incorporating free MP in glutathione-PEGylated liposomes, creating a slow-release formulation with reduced toxicity and prolonged peripheral efficacy. This first-in-human study was designed to assess the safety, pharmacokinetics and pharmacodynamics of glutathione-PEGylated liposomes containing MP (2B3-201). METHODS: The first part was a double-blind, three-way cross over study in 18 healthy male subjects, receiving ascending doses of 2B3-201, active comparator (free MP) or placebo. Part 2 of the study was an open-label infusion of 2B3-201 (different doses), exploring pretreatment with antihistamines and different infusion schedules in another 18 healthy male subjects, and a cross-over study in six healthy female subjects. MP plasma concentrations, lymphocyte counts, adrenocorticotropic hormone, osteocalcin and fasting glucose were determined. Safety and tolerability profiles were assessed based on adverse events, safety measurements and central nervous system tests. RESULTS: The most frequent recorded AE related to 2B3-201 was an infusion related reaction (89%). 2B3-201 was shown to have a plasma half-life between 24 and 37 h and caused a prolonged decrease in the lymphocyte count, adrenocorticotropic hormone and osteocalcin, and a rise in fasting glucose. CONCLUSION: 2B3-201 is considered safe, with no clinically relevant changes in central nervous system safety parameters and no serious adverse events. In addition, 2B3-201 shows a long plasma half-life and prolonged immunosuppressive effects.


Asunto(s)
Preparaciones de Acción Retardada/farmacología , Glutatión/química , Liposomas/química , Metilprednisolona/farmacología , Metilprednisolona/farmacocinética , Hormona Adrenocorticotrópica/sangre , Adulto , Antialérgicos/uso terapéutico , Antiinflamatorios/efectos adversos , Antiinflamatorios/química , Antiinflamatorios/farmacocinética , Glucemia , Clemastina/uso terapéutico , Estudios Cruzados , Preparaciones de Acción Retardada/farmacocinética , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Composición de Medicamentos/métodos , Quimioterapia Combinada/efectos adversos , Femenino , Voluntarios Sanos , Humanos , Liposomas/efectos adversos , Liposomas/farmacocinética , Liposomas/farmacología , Recuento de Linfocitos , Masculino , Metilprednisolona/efectos adversos , Metilprednisolona/química , Osteocalcina/sangre , Polietilenglicoles/química
9.
J Dtsch Dermatol Ges ; 16(1): 34-40, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29280553

RESUMEN

BACKGROUND: The sulfone dapsone has an established role in systemic therapy. Its pharmacological and toxicological properties are well known. Topically, dapsone is used in a gel formulation for the treatment of acne vulgaris. In addition, there have been individual case reports on the efficacy of topical dapsone preparations in the treatment of various neutrophilic dermatoses. To date, no finished medicinal product for topical use has been available in Germany. MATERIAL AND METHODS: Against this background, we set out to develop extemporaneous preparations containing dapsone (5 %) that meet the quality requirements of the European Pharmacopoeia as well as the manufacturing requirements of the German Ordinance on the Operation of Pharmacies (ApBetrO). These formulations included the incorporation of dapsone in a hydrophobic cream base ("hydrophobe Basiscreme DAC") as well as in methylprednisolone aceponate 0.1 % ointment (alternatively, in the latter's cream base without active ingredient). RESULTS: Tests aimed at investigating the physical, chemical, and microbiological stability of these formulations showed them to meet the aforementioned quality requirements. CONCLUSION: The extemporaneous formulations presented herein broaden the therapeutic options for topical treatment, in particular for patients with chronic inflammatory dermatoses associated with a neutrophilic pathogenesis.


Asunto(s)
Dapsona/química , Dapsona/uso terapéutico , Administración Cutánea , Combinación de Medicamentos , Composición de Medicamentos , Estabilidad de Medicamentos , Humanos , Metilprednisolona/análogos & derivados , Metilprednisolona/química , Metilprednisolona/uso terapéutico , Pomadas , Crema para la Piel
10.
Drug Deliv ; 24(1): 1770-1781, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29160134

RESUMEN

The advent of nanomedicine requires novel delivery vehicles to actively target their site of action. Here, we demonstrate the development of lung-targeting drug-loaded liposomes and their efficacy, specificity and safety. Our study focuses on glucocorticoids methylprednisolone (MPS), a commonly used drug to treat lung injuries. The steroidal molecule was loaded into functionalized nano-sterically stabilized unilamellar liposomes (NSSLs). Targeting functionality was performed through conjugation of surfactant protein A (SPANb) nanobodies to form MPS-NSSLs-SPANb. MPS-NSSLs-SPANb exhibited good size distribution, morphology, and encapsulation efficiency. Animal experiments demonstrated the high specificity of MPS-NSSLs-SPANb to the lung. Treatment with MPS-NSSLs-SPANb reduced the levels of TNF-α, IL-8, and TGF-ß1 in rat bronchoalveolar lavage fluid and the expression of NK-κB in the lung tissues, thereby alleviating lung injuries and increasing rat survival. The nanobody functionalized nanoparticles demonstrate superior performance to treat lung injury when compared to that of antibody functionalized systems.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Liposomas/química , Metilprednisolona/química , Metilprednisolona/farmacología , Nanopartículas/química , Proteína A Asociada a Surfactante Pulmonar/química , Animales , Líquido del Lavado Bronquioalveolar/química , Sistemas de Liberación de Medicamentos/métodos , Glucocorticoides/química , Glucocorticoides/farmacología , Interleucina-8/metabolismo , Pulmón/efectos de los fármacos , Masculino , Surfactantes Pulmonares/química , Surfactantes Pulmonares/farmacología , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
11.
Cell Calcium ; 66: 10-18, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28807145

RESUMEN

The transient receptor potential canonical channel 5 (TRPC5) is a Ca2+-permeable ion channel, which is predominantly expressed in the brain. TRPC5-deficient mice exhibit a reduced innate fear response and impaired motor control. In addition, outgrowth of hippocampal and cerebellar neurons is retarded by TRPC5. However, pharmacological evidence of TRPC5 function on cellular or organismic levels is sparse. Thus, there is still a need for identifying novel and efficient TRPC5 channel modulators. We, therefore, screened compound libraries and identified the glucocorticoid methylprednisolone and N-[3-(adamantan-2-yloxy)propyl]-3-(6-methyl-1,1-dioxo-2H-1λ6,2,4-benzothiadiazin-3-yl)propanamide (BTD) as novel TRPC5 activators. Comparisons with closely related chemical structures from the same libraries indicate important substructures for compound efficacy. Methylprednisolone activates TRPC5 heterologously expressed in HEK293 cells with an EC50 of 12µM, while BTD-induced half-maximal activation is achieved with 5-fold lower concentrations, both in Ca2+ assays (EC50=1.4µM) and in electrophysiological whole cell patch clamp recordings (EC50=1.3 µM). The activation resulting from both compounds is long lasting, reversible and sensitive to clemizole, a recently established TRPC5 inhibitor. No influence of BTD on homotetrameric members of the remaining TRPC family was observed. On the main sensory TRP channels (TRPA1, TRPV1, TRPM3, TRPM8) BTD exerts only minor activity. Furthermore, BTD can activate heteromeric channel complexes consisting of TRPC5 and its closest relatives TRPC1 or TRPC4, suggesting a high selectivity of BTD for channel complexes bearing at least one TRPC5 subunit.


Asunto(s)
Benzotiadiazinas/farmacología , Potenciales de la Membrana/efectos de los fármacos , Metilprednisolona/farmacología , Canales Catiónicos TRPC/metabolismo , Animales , Benzotiadiazinas/química , Señalización del Calcio/efectos de los fármacos , Células HEK293 , Humanos , Metilprednisolona/química , Ratones , Microscopía Confocal , Técnicas de Placa-Clamp , Fosfoinositido Fosfolipasa C/metabolismo , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/metabolismo , Subunidades de Proteína/agonistas , Subunidades de Proteína/metabolismo , Canales Catiónicos TRPC/agonistas , Canales Catiónicos TRPC/genética
12.
Int J Mol Med ; 39(4): 851-860, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28259932

RESUMEN

Glucocorticoids (GCs) are commonly used in the treatment of nephrotic syndrome. However, high doses and long periods of GC therapy can result in severe side effects. The present study aimed to selectively deliver albumin­methylprednisolone (MP) nanoparticles towards glomerular podocytes, which highly express the specific neonatal Fc receptor (FcRn) of albumin. Bovine serum albumin (BSA) was labeled with a fluorescent dye and linked with modified MP via an amide bond. The outcome nanoparticle named BSA633­MP showed a uniform size with a diameter of approximately 10 nm and contained 12 drug molecules on average. The nanoconjugates were found to be stable at pH 7.4 and acid­sensitive at pH 4.0, with approximately 72% release of the MP drug after 48 h of incubation. The nanoparticle demonstrated a 36­fold uptake in receptor­specific cellular delivery in the FcRn­expressing human podocytes compared to the uptake in the non-FcRn-expressing control cells. Co­localization further confirmed that uptake of the nanoconjugates involved receptor­mediated endocytosis followed by lysosome associated transportation. In vitro cellular experiments indicated that the BSA633­MP ameliorated puromycin aminonucleoside­induced podocyte apoptosis. Moreover, in vivo fluorescence molecular imaging showed that BSA633-MP was mainly accumulated in the liver and kidney after intravenous dosing for 24 h. Collectively, this study may provide an approach for the effective and safe therapy of nephrotic syndrome.


Asunto(s)
Portadores de Fármacos , Antígenos de Histocompatibilidad Clase I/metabolismo , Metilprednisolona , Nanopartículas/química , Podocitos/metabolismo , Receptores Fc/metabolismo , Albúmina Sérica Bovina , Animales , Apoptosis/efectos de los fármacos , Bovinos , Línea Celular Transformada , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Humanos , Metilprednisolona/química , Metilprednisolona/farmacología , Puromicina Aminonucleósido/efectos adversos , Puromicina Aminonucleósido/farmacología , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/farmacología
13.
Eur J Pharm Sci ; 91: 225-35, 2016 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-27189528

RESUMEN

The objective of this study was to improve the therapeutic efficacy of methylprednisolone acetate (MPA) in the treatment of rheumatoid arthritis (RA) by incorporating the drug into the hydroxyapatite (HAp) nanoparticles. The nanoparticles were synthesized using a chemical precipitation technique and their size and morphology were evaluated by dynamic light scattering and scanning electron microscopy (SEM). The solid-state behavior of the nanoparticles was also characterized by operating X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The Brunauer-Emmett-Teller and Barrett-Joyner-Halenda N2 adsorption/desorption analyses were also performed to determine the surface area, Vm (the volume of the N2 adsorbed on the one gram of the HAp when the monolayer is complete) and the pore size of the samples. Furthermore, the therapeutic efficacy of the prepared nanoformulation on the adjuvant induced arthritic rats was assessed. HAp mesoporous nanoparticles with a particle size of 70.45nm, pore size of 2.71nm and drug loading of 44.53% were obtained. The specific surface area of HAp as well as the Vm values were decreased after the drug loading process. The nanoformulation revealed the slower drug release profile compared to the pure drug. The MTT assay indicated that the MPA-loaded nanoparticles had a lower cytotoxic effect on NIH-3T3 and CAOV-4 cell lines compared to the pure drug. Interestingly, the in vivo study confirmed that the drug-loaded nanoparticles could considerably decrease the paw volume and normalize the hematological abnormalities in the arthritic rats.


Asunto(s)
Antiinflamatorios/administración & dosificación , Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Durapatita/química , Metilprednisolona/análogos & derivados , Nanopartículas/administración & dosificación , Adsorción , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Artritis Experimental/patología , Artritis Reumatoide/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Liberación de Fármacos , Humanos , Articulaciones/efectos de los fármacos , Articulaciones/patología , Masculino , Metilprednisolona/administración & dosificación , Metilprednisolona/química , Metilprednisolona/farmacología , Metilprednisolona/uso terapéutico , Acetato de Metilprednisolona , Ratones , Células 3T3 NIH , Nanopartículas/química , Nanopartículas/uso terapéutico , Alcohol Polivinílico/química , Ratas Wistar
14.
J Diabetes Res ; 2016: 4196460, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26885529

RESUMEN

Tacrolimus and sirolimus are important immunosuppressive drugs used in human islet transplantation; however, they are linked to detrimental effects on islets and reduction of long-term graft function. Few studies investigate the direct effects of these drugs combined in parallel with single drug exposure. Human islets were treated with or without tacrolimus (30 µg/L), sirolimus (30 µg/L), or a combination thereof for 24 hrs. Islet function as well as apoptosis was assessed by glucose-stimulated insulin secretion (GSIS) and Cell Death ELISA. Proinflammatory cytokines were analysed by qRT-PCR and Bio-Plex. Islets exposed to the combination of sirolimus and tacrolimus were treated with or without methylprednisolone (1000 µg/L) and the expression of the proinflammatory cytokines was investigated. We found the following: (i) No additive reduction in function and viability in islets existed when tacrolimus and sirolimus were combined compared to the single drug. (ii) Increased expression of proinflammatory cytokines mRNA and protein levels in islets took place. (iii) Methylprednisolone significantly decreased the proinflammatory response in islets induced by the drug combination. Although human islets are prone to direct toxic effect of tacrolimus and sirolimus, we found no additive effects of the drug combination. Short-term exposure of glucocorticoids could effectively reduce the proinflammatory response in human islets induced by the combination of tacrolimus and sirolimus.


Asunto(s)
Glucocorticoides/administración & dosificación , Islotes Pancreáticos/efectos de los fármacos , Sirolimus/administración & dosificación , Sirolimus/efectos adversos , Tacrolimus/administración & dosificación , Tacrolimus/efectos adversos , Adulto , Apoptosis , Índice de Masa Corporal , Células Cultivadas , Citocinas/metabolismo , Sinergismo Farmacológico , Femenino , Glucosa/química , Humanos , Inmunosupresores/uso terapéutico , Inflamación , Insulina/metabolismo , Secreción de Insulina , Trasplante de Islotes Pancreáticos , Masculino , Metilprednisolona/química , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Mensajero/metabolismo
15.
Nanomedicine ; 12(4): 965-976, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26733264

RESUMEN

6α-Methylprednisolone-loaded surfactant-free nanoparticles have been developed to palliate cisplatin ototoxicity. Nanoparticles were based on two different amphiphilic pseudo-block copolymers obtained by free radical polymerization and based on N-vinyl pyrrolidone and a methacrylic derivative of α-tocopheryl succinate or α-tocopherol. Copolymers formed spherical nanoparticles by nanoprecipitation in aqueous media that were able to encapsulate 6α-methylprednisolone in their inner core. The obtained nanovehicles were tested in vitro using HEI-OC1 cells and in vivo in a murine model. Unloaded nanoparticles were not able to significantly reduce the cisplatin ototoxicity. Loaded nanoparticles reduced cisplatin-ototoxicity in vitro being more active those based on the methacrylic derivative of vitamin E, due to their higher encapsulation efficiency. This formulation was able to protect hair cells in the base of the cochlea, having a positive effect in the highest frequencies tested in a murine model. A good correlation between the in vitro and the in vivo experiments was found. FROM THE CLINICAL EDITOR: Cisplatin is a commonly used chemotherapeutic agent against many cancers clinically. However, one of the significant side-effects remains ototoxicity. Here, the authors presented their data on using 6α-methylprednisolone-loaded nanoparticles in the reduction of ototoxicity in in-vitro and in-vivo experiments. Early promising results should enable further refinement of adopting this new approach in future experiments.


Asunto(s)
Antineoplásicos/administración & dosificación , Cisplatino/administración & dosificación , Metilprednisolona/administración & dosificación , Nanopartículas/administración & dosificación , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/efectos adversos , Apoptosis/efectos de los fármacos , Cisplatino/efectos adversos , Cóclea/efectos de los fármacos , Cóclea/patología , Oído Interno/efectos de los fármacos , Oído Interno/patología , Células Ciliadas Auditivas/efectos de los fármacos , Células Ciliadas Auditivas/patología , Humanos , Metilprednisolona/química , Ratones , Nanopartículas/química , Neoplasias/patología , Sustancias Protectoras/administración & dosificación , Sustancias Protectoras/química , Pirrolidinonas/administración & dosificación , Pirrolidinonas/química , Ratas
16.
Biomed Chromatogr ; 30(9): 1346-53, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26713406

RESUMEN

The present study deals with preparation and optimization of a novel chitosan hydrogel-based matrix by suspension cross-linking method for controlled release of Depo-Medrol. The controlled release of Depo-Medrol for effective Rheumatoid arthritis disease has become an imperative field in the drug delivery system. In this context, it was intended to optimize loading circumstances by experimental design and also study the release kinetics of Depo-Medrol entrapped in the chitosan matrix in order to obtain maximal efficiency for drug loading. The optimum concentrations of chitosan (2.5 g), glutaraldehyde (3.05 µL) and Depo-Medrol (0.1 mg) were set up to achieve the highest value of drug loaded and the most sustained release from the chitosan matrix. In vitro monitoring of drug release kinetic using high-performance liquid chromatography showed that 73% of the Depo-Medrol was released within 120 min, whereas remained drug was released during the next 67 h. High correlation between first-order and Higuchi's kinetic models indicates a controlled diffusion of Depo-Medrol through the surrounding media. Moreover, recovery capacity >82% and entrapment efficiency of 58-88% were achieved under optimal conditions. Therefore, the new synthesized Depo Medrol-chitosan is an applicable appliance for arthritis therapy by slow release mechanism. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Quitosano/química , Cromatografía Líquida de Alta Presión/métodos , Hidrogeles , Metilprednisolona/análogos & derivados , Metilprednisolona/administración & dosificación , Rastreo Diferencial de Calorimetría , Preparaciones de Acción Retardada , Metilprednisolona/química , Metilprednisolona/farmacocinética , Acetato de Metilprednisolona
17.
Artif Cells Nanomed Biotechnol ; 44(2): 497-503, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25289448

RESUMEN

The aim of the present study was to formulate methylprednisolone acetate -Eudragit(®) RS100 nanofibers and nanobeads by the electrospinning method. The physicochemical characteristics of the prepared electrospuns were assessed as well. The particle size and morphology were evaluated using scanning electron microscopy. The crystallinity of the drug in the nanofibers and nanobeads obtained was also studied by X-ray crystallography and differential scanning calorimetry (DSC) thermograms. In addition, FT-IR spectroscopy was applied to investigate any possible chemical interaction between the drug and carrier during the preparation process. The drug release kinetics were considered, to predict the release mechanism. Increasing the concentration of the injected solution resulted in the production of more nanofibers and less nanobeads, with the particle size ranging from 100 to 500 nm. The drug crystallinity was decreased during the electrospinning process; however, no interaction between drug and polymer was observed. The electrospuns showed faster drug release pattern compared to the pure drug. The release data were best fitted to the Weibull model, in which the corresponding shape factor values of the model were less than 0.75 indicating the diffusion mechanism of drug release. In conclusion, electrospinning could be considered as a simple and cost effective method for fabricating the drug: polymer nanofibers and nanobeads.


Asunto(s)
Fenómenos Químicos , Portadores de Fármacos/química , Electricidad , Metilprednisolona/análogos & derivados , Nanofibras/química , Nanotecnología/métodos , Ácidos Polimetacrílicos/química , Liberación de Fármacos , Cinética , Metilprednisolona/química , Acetato de Metilprednisolona
18.
Artículo en Inglés | MEDLINE | ID: mdl-26377799

RESUMEN

BACKGROUND: Inflammatory bowel disease (IBD) is one of the five most prevalent gastrointestinal disease burdens which commonly require lifetime care. Worldwide incidence rate of ulcerative colitis and Crohn's disease is about 16.8% and 13.4% respectively. Colitis is an inflammation of the colon. Colon targeted drug delivery will direct the drug to the colon. The drug will reach at the site of action and hence its side effects as well as dose can be reduced. Recent patent describes treatment of ulcerative colitis using anti CD3 antibodies, with nicotine and anti-depressant drugs, budesonide foam etc. OBJECTIVE: Present study deals with optimization of site targeted methylprednisolone delivery for treatment of colitis. METHOD: Chitosan and Eudragit RS 100 were used as coating polymers. Tablets were prepared by press coated technology. The core tablets contain drug, avicel as binder, croscarmellose sodium as super disintegrant and dicalcium phosphate as diluent. Drug excipient compatibility was carried out using FTIR, UV and DSC. Design of experiment was used to optimize the formulation. Tablets were evaluated for thickness, weight variation, hardness, swelling index, in-vitro drug release and release of drug in simulated media. RESULTS: Optimized batch (B2) contained chitosan 40% and eudragit RS 100 17.5%. B2 showed in-vitro drug release 85.65 ± 7.6% in 6.8 pH phosphate buffer and 96.7 ±9.1% in simulated media after 7.5 hours. CONCLUSION: In-vivo x-ray placebo study for formulation B2 had shown that the tablet reached to the ascending colon after 5 hours. This indicated a potential site targeted delivery of optimized batch B2.


Asunto(s)
Resinas Acrílicas/química , Antiinflamatorios/química , Quitosano/química , Colitis/tratamiento farmacológico , Portadores de Fármacos , Fármacos Gastrointestinales/química , Metilprednisolona/química , Administración Oral , Antiinflamatorios/administración & dosificación , Rastreo Diferencial de Calorimetría , Composición de Medicamentos , Estabilidad de Medicamentos , Fármacos Gastrointestinales/administración & dosificación , Concentración de Iones de Hidrógeno , Cinética , Metilprednisolona/administración & dosificación , Solubilidad , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Comprimidos , Tecnología Farmacéutica/métodos
19.
Pain Physician ; 18(6): E1131-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26606028

RESUMEN

BACKGROUND: Case reports of catastrophic neurological sequelae during ESIs have questioned the safety of this procedure. A proposed mechanism is particulate steroid embolization resulting in neuralischemia. Previous reports have described steroid clumping in common epidural injection mixtures. We demonstrate that physiologic medium can also modify aggregation. OBJECTIVE: To inspect and compare aggregative properties of steroid preparations with and without human serum. SETTING: Academic tertiary care center. HYPOTHESIS: Particulate steroids display different aggregation characteristics in serum compared to non-physiologic solutions. DESIGN: Solutions were inspected under light microscopy: betamethasone sodium phosphate/betamethasone acetate, methylprednisolone, and dexamethasone were each mixed in lidocaine 1%, bupivacaine 0.5%, or sterile water in a 1:1 ratio. All preparations were inspected under light microscopy with 100x and 400x magnifications by a pathologist blinded to our expectations and hypothesis. Five random viewing fields were selected within each slide and the number of aggregates per field and the number of particles per aggregate was evaluated. RESULTS: The addition of serum had a significant effect on steroid particle aggregation and number of particles per aggregate. LIMITATIONS: This study was limited by sample size as only 2 sets of human serum samples were tested with each preparation against one non-serum control. Additionally, as steroid preparations were evaluated under light microscopy, the ex vivo setting must be considered in the interpretation of results. Finally, mixing preparations with human serum as opposed to whole blood was necessary to allow for improved visibility on light microscopy despite the fact that whole blood may be necessary to more closely emulate in vivo coagulation setting. CONCLUSIONS: Overall, the presence of serum resulted in fewer large steroid particle aggregates when compared to non-serum control samples. Amongst particulate steroids, betamethasone with bupivacaine 0.5% demonstrated the fewest and smallest particle aggregates, suggesting that preparation may reduce the risk of embolic infarction. Methylprednisolone formed significantly larger particles in bupivicaine 0.5% with serum compared to non-serum controls.


Asunto(s)
Suero/química , Esteroides/química , Betametasona/química , Bupivacaína/química , Dexametasona/química , Embolia/etiología , Humanos , Inyecciones Epidurales , Lidocaína/química , Metilprednisolona/química , Tamaño de la Partícula , Esteroides/administración & dosificación
20.
J Zhejiang Univ Sci B ; 16(1): 52-61, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25559956

RESUMEN

BACKGROUND AND AIMS: Ingestion of paraquat (PQ), a widely used herbicide, can cause severe toxicity in humans, leading to a poor survival rate and prognosis. One of the main causes of death by PQ is PQ-induced pulmonary fibrosis, for which there are no effective therapies. The aim of this study was to evaluate the effects of rapamycin (RAPA) on inhibiting PQ-induced pulmonary fibrosis in mice and to explore its possible mechanisms. METHODS: Male C57BL/6J mice were exposed to either saline (control group) or PQ (10 mg/kg body weight, intraperitoneally; test group). The test group was divided into four subgroups: a PQ group (PQ-exposed, non-treated), a PQ+RAPA group (PQ-exposed, treated with RAPA at 1 mg/kg intragastrically), a PQ+MP group (PQ-exposed, treated with methylprednisolone (MP) at 30 mg/kg intraperitoneally), and a PQ+MP+RAPA group (PQ-exposed, treated with MP at 30 mg/kg intraperitoneally and with RAPA at 1 mg/kg intragastrically). The survival rate and body weight of all the mice were recorded every day. Three mice in each group were sacrificed at 14 d and the rest at 28 d after intoxication. Lung tissues were excised and stained with hematoxylin-eosin (H&E) and Masson's trichrome stain for histopathological analysis. The hydroxyproline (HYP) content in lung tissues was detected using an enzyme-linked immunosorbent assay (ELISA) kit. The expression of transforming growth factor-ß1 (TGF-ß1) and α-smooth muscle actin (α-SMA) in lung tissues was detected by immunohistochemical staining and Western blotting. RESULTS: A mice model of PQ-induced pulmonary fibrosis was established. Histological examination of lung tissues showed that RAPA treatment moderated the pathological changes of pulmonary fibrosis, including alveolar collapse and interstitial collagen deposition. HYP content in lung tissues increased soon after PQ intoxication but had decreased significantly by the 28th day after RAPA treatment. Immunohistochemical staining and Western blotting showed that RAPA treatment significantly down-regulated the enhanced levels of TGF-ß1 and α-SMA in lung tissues caused by PQ exposure. However, RAPA treatment alone could not significantly ameliorate the lower survival rate and weight loss of treated mice. MP treatment enhanced the survival rate, but had no significant effects on attenuating PQ-induced pulmonary fibrosis or reducing the expression of TGF-ß1 and α-SMA. CONCLUSIONS: This study demonstrates that RAPA treatment effectively suppresses PQ-induced alveolar collapse and collagen deposition in lung tissues through reducing the expression of TGF-ß1 and α-SMA. Thus, RAPA has potential value in the treatment of PQ-induced pulmonary fibrosis.


Asunto(s)
Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/fisiopatología , Sirolimus/uso terapéutico , Actinas/metabolismo , Animales , Peso Corporal , Colágeno/química , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Herbicidas/efectos adversos , Inmunohistoquímica , Inmunosupresores/uso terapéutico , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Metilprednisolona/química , Ratones , Ratones Endogámicos C57BL , Paraquat/efectos adversos , Pronóstico , Fibrosis Pulmonar/inducido químicamente , Factor de Crecimiento Transformador beta1/metabolismo , Resultado del Tratamiento
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