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1.
Analyst ; 149(13): 3615-3624, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38775016

RESUMEN

Mycophenolate mofetil (MpM) is a medication used to prevent the rejection of transplanted organs, particularly in kidney, heart, and liver transplant surgeries. It is extremely important to be conscious that MpM can raise the risk of severe infections and some cancers if it exceeds the recommended dose while lower doses will result in organ rejections. So, it is essential to monitor the dosage of MpM in real time in the micromolar range. In this work, we have synthesized 3-aminopropyltriethoxysilane (APTES) functionalized nickel cobaltite (NiCo2O4) and this amino functionalization was chosen to enhance the stability and electrochemical activity of NiCo2O4. The enhanced activity of NiCo2O4 was used for developing an electrochemical sensor for the detection of MpM. APTES functionalized NiCo2O4 was coated on carbon cloth and used as the working electrode. Surface functionalization with APTES on NiCo2O4 was aimed at augmenting the adsorption/interaction of MpM due to its binding properties. The developed sensor showed a very low detection limit of 1.23 nM with linear ranges of 10-100 nM and 1-100 µM and its practical applicability was examined using artificial samples of blood serum and cerebrospinal fluid, validating its potential application in real-life scenarios.


Asunto(s)
Carbono , Inmunosupresores , Límite de Detección , Ácido Micofenólico , Nanoestructuras , Níquel , Erizos de Mar , Dispositivos Electrónicos Vestibles , Animales , Níquel/química , Ácido Micofenólico/sangre , Ácido Micofenólico/química , Ácido Micofenólico/análisis , Inmunosupresores/sangre , Inmunosupresores/análisis , Inmunosupresores/química , Carbono/química , Erizos de Mar/química , Nanoestructuras/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Propilaminas/química , Humanos , Cobalto/química , Electrodos , Silanos
2.
J Enzyme Inhib Med Chem ; 37(1): 2725-2741, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36189734

RESUMEN

The group of 18 new amide derivatives of mycophenolic acid (MPA) and selected heterocyclic amines was synthesised as potential immunosuppressive agents functioning as inosine-5'-monophosphate dehydrogenase (IMPDH) uncompetitive inhibitors. The synthesis of 14 of them employed uronium-type activating system (TBTU/HOBt/DIPEA) while 4 of them concerned phosphonic acid anhydride method (T3P/Py) facilitating amides to be obtained in moderate to excellent yields without the need of phenolic group protection. Most of optimised protocols did not require complicated reaction work-ups, including chromatographic, solvent-consuming methods. The biological activity assay was performed on the T-Jurkat cell line and peripheral mononuclear blood cells (PBMCs) which are both dedicated for antiproliferative activity determination. Each of designed derivatives was characterised by reduced cytotoxicity and benzoxazole analogue (A2) revealed the most promising activity. Subsequently, an observed structure-activity relationship was discussed.


Asunto(s)
Inmunosupresores , Ácido Micofenólico , Amidas/farmacología , Aminas , Anhídridos , Benzoxazoles , Inhibidores Enzimáticos/farmacología , IMP Deshidrogenasa , Inmunosupresores/química , Inosina , Ácido Micofenólico/química , Solventes
3.
Molecules ; 26(17)2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34500831

RESUMEN

A simple, precise, and accurate reversed-phase ultra-performance liquid chromatographic (UPLC) method was developed and validated for the determination of a mycophenolic acid-curcumin (MPA-CUR) conjugate in buffer solutions. Chromatographic separation was performed on a C18 column (2.1 × 50 mm id, 1.7 µm) with a gradient elution system of water and acetonitrile, each containing 0.1% formic acid, at a flow rate of 0.6 mL/min. The column temperature was controlled at 33 °C. The compounds were detected simultaneously at the maximum wavelengths of mycophenolic acid (MPA), 254 nm, and curcumin (CUR), or MPA-CUR, at 420 nm. The developed method was validated according to the ICH Q2(R1) guidelines. The linear calibration curves of the assay ranged from 0.10 to 25 µg/mL (r2 ≥ 0.995, 1/x2 weighting factor), with a limit of detection and a limit of quantitation of 0.04 and 0.10 µg/mL, respectively. The accuracy and precision of the developed method were 98.4-101.6%, with %CV < 2.53%. The main impurities from the specificity test were found to be MPA and CUR. Other validation parameters, including robustness and solution stability, were acceptable under the validation criteria. Forced degradation studies were conducted under hydrolytic (acidic and alkaline), oxidative, thermal, and photolytic stress conditions. MPA-CUR was well separated from MPA, CUR, and other unknown degradation products. The validated method was successfully applied in chemical kinetic studies of MPA-CUR in different buffer solutions.


Asunto(s)
Cromatografía Liquida/métodos , Curcumina/química , Cinética , Ácido Micofenólico/química , Temperatura
4.
Bioorg Med Chem Lett ; 45: 128135, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34044119

RESUMEN

Twenty six propargylamine mycophenolate analogues were designed and synthesized from mycophenolic acid 1 employing a key step A3-coupling reaction. Their cytotoxic activity was examined against six cancer cell lines. Compounds 6a, 6j, 6t, 6u, and 6z exhibited selective cytotoxicity towards neuroblastoma (SH-SY5Y) cancer cells and were less toxic to normal cells in comparison to the lead compound, MPA 1 and a standard drug, ellipticine. Molecular docking results suggested that compound 6a is fit well in the key amino acid of three proteins (CDK9, EGFR, and VEGFR-2) as targets in cancer therapy. The propargylamine mycophenolate scaffold might be a valuable starting point for development of new neuroblastoma anticancer drugs.


Asunto(s)
Antineoplásicos/farmacología , Ácido Micofenólico/farmacología , Neuroblastoma/tratamiento farmacológico , Pargilina/análogos & derivados , Propilaminas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Ácido Micofenólico/síntesis química , Ácido Micofenólico/química , Neuroblastoma/patología , Pargilina/síntesis química , Pargilina/química , Pargilina/farmacología , Propilaminas/síntesis química , Propilaminas/química , Relación Estructura-Actividad
5.
FEBS J ; 288(19): 5768-5780, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33843134

RESUMEN

Mycophenolic acid (MPA) is a fungal natural product and first-line immunosuppressive drug for organ transplantations and autoimmune diseases. In the compartmentalized biosynthesis of MPA, the acyl-coenzyme A (CoA) hydrolase MpaH' located in peroxisomes catalyzes the highly specific hydrolysis of MPA-CoA to produce the final product MPA. The strict substrate specificity of MpaH' not only averts undesired hydrolysis of various cellular acyl-CoAs, but also prevents MPA-CoA from further peroxisomal ß-oxidation catabolism. To elucidate the structural basis for this important property, in this study, we solve the crystal structures of the substrate-free form of MpaH' and the MpaH'S139A mutant in complex with the product MPA. The MpaH' structure reveals a canonical α/ß-hydrolase fold with an unusually large cap domain and a rare location of the acidic residue D163 of catalytic triad after strand ß6. MpaH' also forms an atypical dimer with the unique C-terminal helices α13 and α14 arming the cap domain of the other protomer and indirectly participating in the substrate binding. With these characteristics, we propose that MpaH' and its homologs form a new subfamily of α/ß hydrolase fold protein. The crystal structure of MpaH'S139A /MPA complex and the modeled structure of MpaH'/MPA-CoA, together with the structure-guided mutagenesis analysis and isothermal titration calorimetry (ITC) measurements, provide important mechanistic insights into the high substrate specificity of MpaH'.


Asunto(s)
Acilcoenzima A/química , Hidrolasas/ultraestructura , Ácido Micofenólico/metabolismo , Peroxisomas/ultraestructura , Secuencia de Aminoácidos/genética , Dominio Catalítico/genética , Hidrolasas/química , Hidrolasas/genética , Ácido Micofenólico/química , Penicillium/genética , Penicillium/ultraestructura , Peroxisomas/enzimología , Estructura Secundaria de Proteína/genética , Especificidad por Sustrato/genética
6.
Theranostics ; 11(8): 3694-3709, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33664856

RESUMEN

Immune-mediated inflammatory diseases (IMIDs) are characterized by immune dysregulation and severe inflammation caused by the aberrant and overactive host immunological response. Mycophenolic acid (MPA)-based immunosuppressive drugs are potential treatments for IMIDs because of their mild side-effect profile; however, their therapeutic effects are limited by the high albumin binding rate, unsatisfactory pharmacokinetics, and undefined cellular uptake selectivity. Methods: Polysaccharide mycophenolate was synthesized by conjugating MPA molecules to dextran (a typical polysaccharide widely used in drug delivery) and encapsulated extra free MPA molecules to fabricate MPA@Dex-MPA nanoparticles (NPs). The efficacy of these NPs for mediating immunosuppression and treatment of IMIDs was evaluated in imiquimod-induced psoriasis-like skin inflammation in Balb/c mice, a representative IMID model. Results: The MPA@Dex-MPA NPs exhibited high MPA loading efficiency, low albumin binding rates, and sustained MPA release, resulting in improved pharmacokinetics in vivo. Compared to free MPA, MPA@Dex-MPA NPs induced more robust therapeutic effects on IMIDs. Mechanistic studies indicated that MPA@Dex-MPA NPs were primarily distributed in dendritic cells (DCs) and significantly suppressed the overactivated DCs in vivo and in vitro. Furthermore, the recovered DCs rehabilitated the IL-23/Th17 axis function and significantly ameliorated imiquimod-induced psoriasis-like skin inflammation. Importantly, MPA@Dex-MPA NPs showed favorable safety and biocompatibility in vivo. Conclusion: Our results indicated the polysaccharide mycophenolate-based NPs to be highly promising for IMID treatment.


Asunto(s)
Inmunosupresores/administración & dosificación , Inflamación/tratamiento farmacológico , Ácido Micofenólico/análogos & derivados , Animales , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Terapia de Inmunosupresión , Inmunosupresores/química , Inmunosupresores/farmacocinética , Inflamación/inmunología , Inflamación/patología , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Ácido Micofenólico/administración & dosificación , Ácido Micofenólico/química , Nanopartículas/administración & dosificación , Nanopartículas/química , Nanopartículas/toxicidad , Polisacáridos/administración & dosificación , Polisacáridos/química , Medicina de Precisión , Psoriasis/tratamiento farmacológico , Psoriasis/inmunología , Psoriasis/patología , Ratas , Ratas Sprague-Dawley
7.
Anticancer Agents Med Chem ; 21(4): 462-467, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32416705

RESUMEN

BACKGROUND: Although Mycophenolic Acid (MPA) is applied as prodrugs in clinic as an immunosuppressant, it also possesses anticancer activity. MPA acts as Inosine-5'-Monophosphate Dehydrogenase (IMPDH) inhibitor, where the carboxylic group at the end of the side chain interacts with Ser 276 of the enzyme via hydrogen bonds. Therefore, MPA derivatives with other polar groups indicated high inhibition too. On the other hand, potent anticancer agents like dacarbazine and cisplatin give numerous side-effects. OBJECTIVE: Based on the literature data, MPA derivatives should be explored towards anticancer properties. Conversion of the carboxylic group of MPA to amide could maintain antiproliferative activity. Therefore, we decided to investigate several amino acid and peptide derivatives of MPA against chosen cancer cell lines in vitro. METHODS: Amides of MPA hold threonine and arginine amino acid unit. These amino acid derivatives were tested as L and D enantiomers and both in free acid and methyl esters forms. Additionally, MPA was modified with tuftsin or retro-tuftsin as biologically active peptides, which could act as a drug carrier. RESULTS: Amino acid and peptide derivatives of MPA were investigated in vitro as potential anticancer agents on cell lines: Ab melanoma, A375 melanoma and SHSY5Y neuroblastoma. The activity of the tested compounds was compared to parent MPA and known chemotherapeutics: dacarbazine and cisplatin. CONCLUSION: Amino acid moiety and the sequence of amino acids in the peptide part influenced observed activity. The most active amino acid MPA analogues occurred to be D and L-threonine derivatives as methyl esters, probably due to better cell membrane penetration.


Asunto(s)
Aminoácidos/farmacología , Antineoplásicos/farmacología , Ácido Micofenólico/farmacología , Péptidos/farmacología , Aminoácidos/síntesis química , Aminoácidos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Mitocondrias/efectos de los fármacos , Estructura Molecular , Ácido Micofenólico/síntesis química , Ácido Micofenólico/química , Péptidos/síntesis química , Péptidos/química , Relación Estructura-Actividad
8.
Biomed Chromatogr ; 35(3): e5011, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33119895

RESUMEN

This study presents, for the first time, the development and validation of a liquid chromatography and time-of-flight mass-spectrometry (LC-TOF-MS) based assay to quantify mycophenolic acid (MPA) in patient samples as part of a routine therapeutic drug monitoring service. MPA was extracted from 50 µl human plasma by protein precipitation, using sulindac as internal standard (IS). Separation was obtained on a Luna™ Omega polar C18 column kept at 40°C. The mobile phase consisted of a mixture of acetonitrile-deionized water (50:50, v/v) with 0.1% formic acid at a flow rate of 350 µl/min. Analyte and IS were monitored on a TOF-MS using a Jet-Stream™ (electrospray) interface running in positive mode. Assay performance was evaluated by analysing patient plasma (N = 69) and external quality assessment (N = 6) samples. The retention times were 2.66 and 2.18 min for MPA and IS, respectively. The lower limit of quantification of MPA was 0.1 µg/ml. The within- and between-assay reproducibility results ranged from 1.81 to 10.72%. Patient and external quality assessment sample results were comparable with those obtained previously by an in-house validated LC-MS/MS method. This method showed satisfactory analytical performance for the determination of MPA in plasma over the calibration range of 0.1-15.0 µg/ml.


Asunto(s)
Cromatografía Liquida/métodos , Monitoreo de Drogas/métodos , Inmunosupresores/sangre , Ácido Micofenólico/sangre , Espectrometría de Masa por Ionización de Electrospray/métodos , Humanos , Inmunosupresores/química , Inmunosupresores/farmacocinética , Modelos Lineales , Ácido Micofenólico/química , Ácido Micofenólico/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Int J Nanomedicine ; 15: 5603-5612, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848390

RESUMEN

INTRODUCTION: Organ transplantation is a critically important procedure, which requires immune modulation by using immunosuppressants. Development of nanoparticles is an emerging and beneficial engineering process to increase the dissolution rate of poorly soluble immunosuppressants as well as to provide controlled release for better therapeutic outcomes. METHOD: Currently, the nanoprecipitation method was employed to fabricate ß-cyclodextrin (ßCD) facilitated mycophenolate mofetil (MMF)-loaded solid lipid nanoparticles (SLNPs). The prime objectives of the study included, improvement of the dissolution profile of poorly aqueous soluble drug and controlled release from the SLNs to provide steady state drug concentration. Drug release from the prepared SLNs was assessed in two different media, ie, acidic buffer at pH 1.2 and phosphate buffer at pH 7.2 using USP dissolution apparatus for 12 h, followed by the evaluation of drug release mechanism and pattern by applying kinetic models. RESULTS: Justifiably, in acidic medium, the release was found to be 12% more (68%) in comparison to that in basic medium (56%). However, in both dissolution media, drug release was independent of initial concentration (R2>0.95) with non-Fickian type of diffusion mechanism. The outcomes of the study have exhibited that prepared formulations were in nanosized range (80-170 nm) with a net charge of ±23 charge on their surface. They possessed fairly uniform surface with acceptable polydispersity index (0.23±0.09). Scanning electron microscopy (SEM) analysis illustrated that the nanoparticles had uniform particle size and shape. DISCUSSION: The findings show potential applications of the nanoparticles and the method for the development of SLNPs in controlled release of MMF for better therapeutic outcomes. Conclusively, the prepared SLNPs were well designed in nanosized ranges and justifying the once daily controlled release formulation dose of MMF to enhance patient compliance.


Asunto(s)
Portadores de Fármacos/química , Inmunosupresores/farmacocinética , Ácido Micofenólico/farmacocinética , Nanopartículas/química , Disponibilidad Biológica , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Difusión , Portadores de Fármacos/farmacocinética , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Concentración de Iones de Hidrógeno , Inmunosupresores/química , Lípidos/química , Microscopía Electrónica de Rastreo , Ácido Micofenólico/química , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Solubilidad , beta-Ciclodextrinas/química
10.
Eur J Med Chem ; 189: 112091, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32007665

RESUMEN

Mycophenolic acid (MPA) was coupled with amino acids and biologically active peptides including derivatives of tuftsin to modify its immunosuppressive properties. Both amino acid unit in the case of simple MPA amides and modifications within peptide moiety of MPA - tuftsin conjugates influenced the observed activity. Antiproliferative potential of the obtained conjugates was investigated in vitro and MPA amides with threonine methyl ester and conjugate of MPA with retro-tuftisin occurred to be more selective against PBMC in comparison to parent MPA. Both amino acid and peptide derivatives of MPA acted as inosine-5'-monophosphate dehydrogenaze (IMPDH) inhibitors.


Asunto(s)
Aminoácidos/química , Proliferación Celular , Inhibidores Enzimáticos/farmacología , Inmunosupresores/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Ácido Micofenólico/química , Fragmentos de Péptidos/química , Inhibidores Enzimáticos/química , Humanos , IMP Deshidrogenasa/antagonistas & inhibidores , Inmunosupresores/química , Células Jurkat , Estructura Molecular , Relación Estructura-Actividad
11.
Appl Biochem Biotechnol ; 191(2): 867-880, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31907779

RESUMEN

The microbial fermentation of Penicillium brevicompactum produces secondary metabolite mycophenolic acid (MPA), which exhibits antifungal, antiviral, antibacterial, and antitumor activity. It is also a potent, selective, non-competitive, and reversible inhibitor of the human inosine monophosphate dehydrogenase (IMPDH). This study is an attempt to optimize the MPA production through a fermentation process using Penicillium brevicompactum and its further purification process optimization. In the batch fermentation process, the maximum concentration of MPA (1.84 g/L) was attained in a 3.7 L stirred tank reactor. Response surface methodology (RSM) using central composite design (CCD) was employed as a statistical tool to investigate the effect of pH, the volume of eluent and flow rate of the mobile phase on MPA purification process. Under optimum conditions, the experimental yield was observed to be 84.12%, which matched well with the predictive yield of 84.42%. High-performance liquid chromatography (HPLC) and Fourier-transform infrared spectroscopy (FTIR) analysis of the fermented product was carried out to confirm the presence of mycophenolic acid. The MPA purification was done by using column chromatography technique. The purification of broth involved mycophenolic acid extraction by selecting different solvents on the basis of polarity and the extraction efficiency of solvent. Various solid support materials were used for MPA purification in column chromatography. The MPA recovery through alumina column was observed to be 84.12% under the optimum conditions, which was maximum elution as compared with other support materials. The optimized purification process yielded pure MPA crystals.


Asunto(s)
Ácido Micofenólico/aislamiento & purificación , Ácido Micofenólico/metabolismo , Penicillium/metabolismo , Biomasa , Reactores Biológicos , Cromatografía , Cromatografía Líquida de Alta Presión , Medios de Cultivo/química , Fermentación , Glucosa , Concentración de Iones de Hidrógeno , IMP Deshidrogenasa/antagonistas & inhibidores , Ácido Micofenólico/química , Metabolismo Secundario
12.
Nanomedicine ; 24: 102147, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31884040

RESUMEN

Mycophenolic acid (MPA) has promising anticancer properties; however, it has limited clinical applications in vivo due to hydrophobic nature, high first-pass metabolism, lack of targeting, etc. These associated problems could be addressed by developing a suitable delivery vehicle, inhibiting the first-pass metabolism and additive/synergistic pharmacodynamic effect. Thus, MPA loaded highly stable lipid polymer hybrid nanoparticles (LPNs) were developed and investigated with the combination of quercetin (QC), a CYP 450 inhibitor cum anticancer. LPNs of MPA and QC (size; 136 ±â€¯12 and 176 ±â€¯35 nm, respectively) demonstrated higher cellular uptake and cytotoxicity of combination therapy (MPA-LPN + QC-LPN) compared to individual congeners in MCF-7 cells. In vivo pharmacokinetics demonstrated 2.17 fold higher T1/2 value and significantly higher pharmacodynamic activity in case of combination therapy compared to free MPA. In nutshell, the combinatory therapeutic regimen of MPA and QC could be a promising approach in improved breast cancer management.


Asunto(s)
Lípidos/química , Ácido Micofenólico/química , Nanopartículas/química , Polímeros/química , Quercetina/química , Animales , Antioxidantes/química , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Femenino , Humanos , Células MCF-7 , Ácido Micofenólico/uso terapéutico , Quercetina/uso terapéutico , Espectroscopía Infrarroja por Transformada de Fourier
13.
Nat Prod Res ; 34(9): 1206-1212, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30760051

RESUMEN

Mycophenolic acid (MPA) is a group of metabolite derived from several species of Penicillium, which shows potent bioactivity. In this study, a new derivative of MPA compound named penicacid D (1), was isolated from the marine derived fungus Penicillium sp. SCSIO sof101, along with seven known compounds (2-8). Their structures were elucidated based on the HR-ESI-MS and NMR data. Moreover, the 1H and 13C NMR data of compound 2 and the 13C NMR data of compound 3 are reported. Compounds 1, 4 and 6 exhibited weak activities against Escherichia coli (clinical isolation number 100385570) and Acinetobacter baumannii (clinical isolation number 100069).


Asunto(s)
Ácido Micofenólico/aislamiento & purificación , Penicillium/química , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Hongos/química , Estructura Molecular , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/química , Ácido Micofenólico/farmacología , Análisis Espectral/métodos
14.
Protein Sci ; 29(3): 686-694, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31675145

RESUMEN

Mycophenolic acid (MPA) is a potent natural product inhibitor of fungal and other eukaryotic inosine 5'-monophosphate dehydrogenases (IMPDHs) originally isolated from spoiled corn silage. MPA is produced by the filamentous fungi Penicillium brevicompactum, which contains two IMPDHs, PbIMPDHA and PbIMPDHB, both of which are MPA-resistant. The MPA binding sites of these enzymes are identical to MPA-sensitive IMPDHs, so the structural determinants of resistance are unknown. Here we show that a single residue, Ser267, accounts for the MPA resistance of PbIMPDHA. Substitution of Ser267 with Ala, the residue most commonly found in this position in eukaryotic IMPDHs, makes PbIMPDHA sensitive to MPA. Conversely, Aspergillus nidulans IMPDH becomes MPA-resistant when the analogous Ala residue is substituted with Ser. These substitutions have little effect on the catalytic cycles of either enzyme, suggesting the fitness costs are negligible despite the strong conservation of Ala at this position. Intriguingly, while only 1% of fungal IMPDHs contain Ser or Thr at position 267, these residues are found in the IMPDHs from several Aspergillus species that grow at the low temperatures also favored by Penicillium. Perhaps Ser/Thr267 is an evolutionary signature of MPA exposure.


Asunto(s)
Antifúngicos/farmacología , Farmacorresistencia Fúngica/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Células Eucariotas/efectos de los fármacos , IMP Deshidrogenasa/antagonistas & inhibidores , Ácido Micofenólico/farmacología , Penicillium/efectos de los fármacos , Antifúngicos/química , Aspergillus/efectos de los fármacos , Aspergillus/enzimología , Inhibidores Enzimáticos/química , Células Eucariotas/metabolismo , IMP Deshidrogenasa/metabolismo , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Ácido Micofenólico/química , Penicillium/enzimología
15.
Handb Exp Pharmacol ; 261: 441-469, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31820175

RESUMEN

The goal of immunosuppressive therapy post-transplantation in pediatric renal transplant recipients is to prevent acute and chronic rejection while minimizing drug side effects. Most therapies alter immune response mechanisms but are not immunologically specific, and a careful balance is required to find the dose that prevents rejection of the graft while minimizing the risks of overimmunosuppression leading to infection and cancer. While this chapter because of space constraints focuses on immunosuppressive therapy in pediatric renal transplant recipients, many aspects can be applied on pediatric recipients of other solid organ transplants such as the liver and heart. The major maintenance immunosuppressive agents currently used in various combination regimens are tacrolimus, cyclosporine, mycophenolate mofetil, azathioprine, everolimus, sirolimus, and glucocorticoids (steroids). Although data from adult renal transplantation trials are used to help guide management decisions in pediatric patients, immunosuppressive therapy in pediatric renal transplant recipients often must be modified because of the unique dosage requirements and clinical effects of these agents in children, including their impact on growth and development. The optimal immunosuppressive therapy post-transplant is not established. The goal remains to find the best combination of immunosuppressive agents that optimizes allograft survival by preventing acute rejection while limiting drug toxicities.


Asunto(s)
Rechazo de Injerto , Inmunosupresores , Adulto , Niño , Ciclosporina/química , Quimioterapia Combinada , Humanos , Ácido Micofenólico/química , Ácido Micofenólico/farmacología , Ácido Micofenólico/uso terapéutico , Tacrolimus/uso terapéutico
16.
Biomater Sci ; 8(1): 266-277, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31690897

RESUMEN

Allotransplantation offers the potential to restore the anatomy and function of injured tissues and organs, but typically requires life-long, systemic administration of immunosuppressive drugs to prevent rejection, which can result in serious complications. Targeting the immunosuppressive drug to the graft favors local tissue concentration versus systemic drug exposure and end-organ toxicity. This could reduce the overall dose and dosing frequency of immunosuppressive drugs, and improve the safety and efficacy of treatment. Here, we developed dibenzocyclooctyne (DBCO)-modified prodrugs of the immunosuppressive drugs tacrolimus, rapamycin and mycophenolic acid, and demonstrated their targeted conjugation both in vitro and in vivo to azido-modified hydrogels via Click chemistry. Such azido-modified hydrogels placed in transplanted tissues enable sustained local release of drugs, and could be repeatedly refilled with systemically administered acid-labile prodrugs after drug exhaustion. Thus, clickable prodrugs with degradable linkers provide new possibilities for graft targeted immunosuppression in the context of allotransplantation.


Asunto(s)
Química Clic , Inmunosupresores/química , Profármacos/química , Alginatos/química , Animales , Portadores de Fármacos/química , Liberación de Fármacos , Semivida , Hidrocarburos Cíclicos/química , Hidrogeles/química , Concentración de Iones de Hidrógeno , Inmunosupresores/metabolismo , Ratones , Ratones Endogámicos BALB C , Ácido Micofenólico/química , Profármacos/metabolismo , Sirolimus/química , Tacrolimus/química
17.
Biomed Chromatogr ; 33(12): e4681, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31419321

RESUMEN

To implement and validate an analytical method by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC MS/MS) to quantify mycophenolic acid (MPA) in kidney transplant patients. Quantification of MPA was performed in an ACQUITY UPLC H Class system coupled to a Xevo TQD detector and it was extracted from plasma samples by protein precipitation. The chromatographic separation was achieved through an ACQUITY HSS C18 SB column with 0.1% formic acid and acetonitrile (60:40 vol/vol) as mobile phase. The pharmacokinetic parameters were calculated by non-compartmental analysis of MPA plasma concentrations from 10 kidney transplant patients. The linear range for MPA quantification was 0.2-30 mg/L with a limit of detection of 0.07 mg/L; the mean extraction recovery was 99.99%. The mean intra- and inter-day variability were 2.98% and 3.4% with a percentage of deviation of 8.4% and 6.6%, respectively. Mean maximal concentration of 10 mg/L at 1.5 h, area under the concentration-time curve of 36.8 mg·h/L, elimination half-life of 3.9 h, clearance of 0.32 L/h/kg and volume of distribution of 1.65 L/kg were obtained from MPA pharmacokinetics profiles. A simple, fast and reliable UPLC-MS/MS method to quantify MPA in plasma was validated and has been applied for pharmacokinetic analysis in kidney transplant patients.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Trasplante de Riñón , Ácido Micofenólico/sangre , Ácido Micofenólico/farmacocinética , Espectrometría de Masas en Tándem/métodos , Adolescente , Adulto , Femenino , Humanos , Límite de Detección , Modelos Lineales , Masculino , Ácido Micofenólico/química , Reproducibilidad de los Resultados , Receptores de Trasplantes , Adulto Joven
18.
Environ Toxicol Chem ; 38(10): 2259-2278, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31225916

RESUMEN

An environmental risk assessment is presented for mycophenolic acid (MPA), an immunosuppressive pharmaceutical used for prevention of organ rejection, and its prodrug mycophenolate mofetil (MPM). Mycophenolic acid will not significantly adsorb to activated sludge. In activated sludge, 14 C-MPA attained >80% degradation, supporting an older environmental fate test with the same compound. Based on n-octanol/water distribution coefficient (log DOW ) values of 2.28, 0.48, and ≤-1.54 at pH 5, 7, and 9, respectively, MPA is not expected to bioaccumulate. Sales amounts of MPA+MPM in Europe were used to derive predicted environmental concentrations (PECs) in surface waters; PECs were refined by including expected biodegradation in sewage treatment, average drinking water use, and average dilution of the effluents in the receiving waters per country. In addition, the exposure to pharmaceuticals in the environment (ePiE) model was run for 4 European catchments. The PECs were complemented with 110 measured environmental concentrations (MECs), ranging from below the limit of quantitation (<0.001 µg/L) to 0.656 µg/L. Predicted no-effect concentrations (PNECs) were derived from chronic tests with cyanobacteria, green algae, daphnids, and fish. The comparison of PECs and MECs with the PNECs resulted in a differentiated environmental risk assessment in which the risk ratio of PEC/PNEC or MEC/PNEC was <1 in most cases (mostly >90%), meaning no significant risk, but a potential risk to aquatic organisms in generally <10% of instances. Because this assessment reveals a partial risk, the following questions must be asked: How much risk is acceptable? and Through which measures can this risk be reduced? These questions are all the more important in view of limited alternatives for MPM and MPA and the serious consequences of not using them. Environ Toxicol Chem 2019;38:2259-2278. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.


Asunto(s)
Monitoreo del Ambiente , Ácido Micofenólico/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , Animales , Organismos Acuáticos/efectos de los fármacos , Chlorophyta/efectos de los fármacos , Farmacorresistencia Microbiana , Europa (Continente) , Peces , Humanos , Modelos Teóricos , Ácido Micofenólico/química , Aguas del Alcantarillado/química , Pruebas de Toxicidad , Contaminantes Químicos del Agua/química
19.
J Sep Sci ; 42(16): 2650-2659, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31197944

RESUMEN

Mycophenolate mofetil is an antiproliferative immunosuppressive agent. Since its clinical efficacy and safety highly depend on the quality, the stability, and impurity profiles of mycophenolate mofetil are paid ever-increasing attention. However, there are few published studies reporting the complete characterization of both the process-related substances and degradation products in mycophenolate mofetil. In the present study, a highly specific and efficient liquid chromatography coupled with quadrupole-time of flight mass spectrometry method was developed for the separation and identification of all the potential impurities in mycophenolate mofetil. According to the ICH Q1A (R2) guideline, the forced degradation studies were conducted to elucidate the stability and degradation pathways of mycophenolate mofetil. A total of 15 related substances, including the process-related substances and stress degradation products were characterized by the established hyphenated method, 11 of them have not been reported before. In view of the synthetic route and degradation pathways of mycophenolate mofetil, the origins and formation mechanisms of these related substances were discussed. Based on the obtained stability and impurity profiles, key points of the manufacturing process were proposed to deliver mycophenolate mofetil with high purity.


Asunto(s)
Ácido Micofenólico/aislamiento & purificación , Cromatografía Liquida , Espectrometría de Masas , Estructura Molecular , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/química , Factores de Tiempo
20.
Biomed Chromatogr ; 33(7): e4529, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30845352

RESUMEN

Stability studies are necessary in healthcare settings as they facilitate fast, cost-effective and efficient work related to batch manufacturing and availability of supplies. We studied the stability of 1-10 mg/mL mycophenolate mofetil (MMF) in polypropylene 5% dextrose infusion bags prepared from Cellcept® and with a generic brand name (Micofenolato de Mofetilo Accord) at different storage temperatures. To ensure chemical compatibility during preparation, we also tested MMF sorption to the Equashield® closed-system drug transfer device used in this step. For this, a validated stability-indicating high-performance liquid chromatography method was developed for the quantification and identification of MMF in the infusion bags. The analytical selectivity of the assay was determined by subjecting an MMF sample to extreme values of pH, oxidative stress and heat conditions to force degradation. Protected from light, 1-10 mg/mL MMF in infusion polypropylene bags prepared from reconstituted Cellcept® 500 mg or Accord 500 mg in 5% dextrose was stable for at least 35 days when stored at 2-8°C or between -15 and -25°C, and for 14 days when stored at 25°C. MMF loss owing to chemical sorption to the Equashield® closed-system drug transfer device set was negligible.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Glucosa/química , Ácido Micofenólico , Polipropilenos/química , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Ácido Micofenólico/análisis , Ácido Micofenólico/química
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