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1.
Int J Mol Sci ; 22(18)2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34575975

RESUMEN

Several classes of immunomodulators are used for treating relapsing-remitting multiple sclerosis (RRMS). Most of these disease-modifying therapies, except teriflunomide, carry the risk of progressive multifocal leukoencephalopathy (PML), a severely debilitating, often fatal virus-induced demyelinating disease. Because teriflunomide has been shown to have antiviral activity against DNA viruses, we investigated whether treatment of cells with teriflunomide inhibits infection and spread of JC polyomavirus (JCPyV), the causative agent of PML. Treatment of choroid plexus epithelial cells and astrocytes with teriflunomide reduced JCPyV infection and spread. We also used droplet digital PCR to quantify JCPyV DNA associated with extracellular vesicles isolated from RRMS patients. We detected JCPyV DNA in all patients with confirmed PML diagnosis (n = 2), and in six natalizumab-treated (n = 12), two teriflunomide-treated (n = 7), and two nonimmunomodulated (n = 2) patients. Of the 21 patients, 12 (57%) had detectable JCPyV in either plasma or serum. CSF was uniformly negative for JCPyV. Isolation of extracellular vesicles did not increase the level of detection of JCPyV DNA versus bulk unprocessed biofluid. Overall, our study demonstrated an effect of teriflunomide inhibiting JCPyV infection and spread in glial and choroid plexus epithelial cells. Larger studies using patient samples are needed to correlate these in vitro findings with patient data.


Asunto(s)
Crotonatos/farmacología , Virus ADN/efectos de los fármacos , Hidroxibutiratos/farmacología , Leucoencefalopatía Multifocal Progresiva/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Neuroglía/efectos de los fármacos , Nitrilos/farmacología , Toluidinas/farmacología , Astrocitos/efectos de los fármacos , Astrocitos/virología , Línea Celular , Plexo Coroideo/efectos de los fármacos , Plexo Coroideo/virología , Virus ADN/patogenicidad , Enfermedades Desmielinizantes/tratamiento farmacológico , Enfermedades Desmielinizantes/patología , Enfermedades Desmielinizantes/virología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/virología , Vesículas Extracelulares/efectos de los fármacos , Vesículas Extracelulares/virología , Humanos , Factores Inmunológicos/efectos adversos , Factores Inmunológicos/uso terapéutico , Virus JC/efectos de los fármacos , Virus JC/patogenicidad , Leucoencefalopatía Multifocal Progresiva/inducido químicamente , Leucoencefalopatía Multifocal Progresiva/patología , Leucoencefalopatía Multifocal Progresiva/virología , Esclerosis Múltiple Recurrente-Remitente/genética , Esclerosis Múltiple Recurrente-Remitente/patología , Esclerosis Múltiple Recurrente-Remitente/virología , Neuroglía/virología , Virosis/tratamiento farmacológico , Virosis/genética , Virosis/virología
2.
J Neuroinflammation ; 17(1): 9, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31915017

RESUMEN

BACKGROUND: The multi-drug resistance transporter ABCG2, a member of the ATP-binding cassette (ABC) transporter family, mediates the efflux of different immunotherapeutics used in multiple sclerosis (MS), e.g., teriflunomide (teri), cladribine, and mitoxantrone, across cell membranes and organelles. Hence, the modulation of ABCG2 activity could have potential therapeutic implications in MS. In this study, we aimed at investigating the functional impact of abcg2 modulation on teri-induced effects in vitro and in vivo. METHODS: T cells from C57BL/6 J wild-type (wt) and abcg2-knockout (KO) mice were treated with teri at different concentrations with/without specific abcg2-inhibitors (Ko143; Fumitremorgin C) and analyzed for intracellular teri concentration (HPLC; LS-MS/MS), T cell apoptosis (annexin V/PI), and proliferation (CSFE). Experimental autoimmune encephalomyelitis (EAE) was induced in C57BL/6J by active immunization with MOG35-55/CFA. Teri (10 mg/kg body weight) was given orally once daily after individual disease onset. abcg2-mRNA expression (spinal cord, splenic T cells) was analyzed using qRT-PCR. RESULTS: In vitro, intracellular teri concentration in T cells was 2.5-fold higher in abcg2-KO mice than in wt mice. Teri-induced inhibition of T cell proliferation was two fold increased in abcg2-KO cells compared to wt cells. T cell apoptosis demonstrated analogous results with 3.1-fold increased apoptosis after pharmacological abcg2-inhibition in wt cells. abcg2-mRNA was differentially regulated during different phases of EAE within the central nervous system and peripheral organs. In vivo, at a dosage not efficacious in wt animals, teri treatment ameliorated clinical EAE in abcg2-KO mice which was accompanied by higher spinal cord tissue concentrations of teri. CONCLUSION: Functional relevance of abcg2 modulation on teri effects in vitro and in vivo warrants further investigation as a potential determinant of interindividual treatment response in MS, with potential implications for other immunotherapies.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/fisiología , Crotonatos/uso terapéutico , Modelos Animales de Enfermedad , Inmunoterapia/métodos , Esclerosis Múltiple/inmunología , Linfocitos T/inmunología , Toluidinas/uso terapéutico , Animales , Crotonatos/farmacología , Femenino , Humanos , Hidroxibutiratos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Esclerosis Múltiple/tratamiento farmacológico , Nitrilos , Ratas , Linfocitos T/efectos de los fármacos , Toluidinas/farmacología
3.
Bioorg Med Chem ; 28(1): 115232, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31818630

RESUMEN

Glucose flux through glucokinase (GK) controls insulin release from the pancreas in response to high levels of glucose. Flux through GK is also responsible for reducing hepatic glucose output. Since many individuals with type 2 diabetes appear to have an inadequacy or defect in one or both of these processes, identifying compounds that can activate GK could provide a therapeutic benefit. Herein we report the further structure activity studies of a novel series of glucokinase activators (GKA). These studies led to the identification of pyridine 72 as a potent GKA that lowered post-prandial glucose in normal C57BL/6J mice, and after 14d dosing in ob/ob mice.


Asunto(s)
Activadores de Enzimas/química , Glucoquinasa/química , Hipoglucemiantes/química , Animales , Sitios de Unión , Glucemia/análisis , Cristalografía por Rayos X , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Activadores de Enzimas/metabolismo , Activadores de Enzimas/uso terapéutico , Glucoquinasa/metabolismo , Prueba de Tolerancia a la Glucosa , Hipoglucemiantes/metabolismo , Hipoglucemiantes/uso terapéutico , Cinética , Ratones , Ratones Endogámicos C57BL , Simulación de Dinámica Molecular , Relación Estructura-Actividad , Tiadiazoles/química , Tiadiazoles/metabolismo
4.
J Labelled Comp Radiopharm ; 63(11): 482-487, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32726870

RESUMEN

Bruton's tyrosine kinase (BTK) is a key component in the B-cell receptor signaling pathway and is consequently a target for in vivo imaging of B-cell malignancies as well as in multiple sclerosis (MS) with positron emission tomography (PET). A recent Phase 2b study with Sanofi's BTK inhibitor, Tolebrutinib (also known as [a.k.a.] SAR442168, PRN2246, or BTK'168) showed significantly reduced disease activity associated with MS. Herein, we report the radiosynthesis of [11 C]Tolebrutinib ([11 C]5) as a potential PET imaging agent for BTK. The N-[11 C]acrylamide moiety of [11 C]5 was labeled by 11 C-carbonylation starting from [11 C]CO, iodoethylene, and the secondary amine precursor via a novel palladium-NiXantphos-mediated carbonylation protocol, and the synthesis was fully automated using a commercial carbon-11 synthesis platform (TracerMaker™, Scansys Laboratorieteknik). [11 C]5 was obtained in a decay-corrected radiochemical yield of 37 ± 2% (n = 5, relative to starting [11 C]CO activity) in >99% radiochemical purity, with an average molar activity of 45 GBq/µmol (1200 mCi/µmol). We envision that this methodology will be generally applicable for the syntheses of labeled N-acrylamides.


Asunto(s)
Agammaglobulinemia Tirosina Quinasa/antagonistas & inhibidores , Radioisótopos de Carbono/química , Paladio/química , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Tolmetina/química , Tolmetina/síntesis química , Técnicas de Química Sintética , Tomografía de Emisión de Positrones , Inhibidores de Proteínas Quinasas/farmacología , Radioquímica , Tolmetina/farmacología
5.
FEMS Yeast Res ; 19(6)2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31505595

RESUMEN

Microorganisms have evolved to produce specific end products for many reasons, including maintaining redox balance between NAD+ and NADH. The yeast Saccharomyces cerevisiae, for example, produces ethanol as a primary end product from glucose for the regeneration of NAD+. Engineered S. cerevisiae strains have been developed to ferment lignocellulosic sugars, such as xylose, to produce lactic acid by expression of a heterologous lactate dehydrogenase (ldhA from Rhizopus oryzae) without genetic perturbation to the native ethanol pathway. Surprisingly, the engineered yeast strains predominantly produce ethanol from glucose, but produce lactic acid as the major product from xylose. Here, we provide initial evidence that the shift in product formation from ethanol to lactic acid during xylose fermentation is at least partially dependent on the presence of functioning monocarboxylate transporter genes/proteins, including JEN1 and ADY2, which are downregulated and unstable in the presence of glucose, but upregulated/stable on xylose. Future yeast metabolic engineering studies may find the feedstock/carbon selection, such as xylose, an important step toward improving the yield of target end products.


Asunto(s)
L-Lactato Deshidrogenasa/metabolismo , Ácido Láctico/metabolismo , Proteínas de Transporte de Membrana/genética , Ingeniería Metabólica , Rhizopus/enzimología , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Xilosa/metabolismo , Regulación hacia Abajo , Etanol/metabolismo , Fermentación , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expresión Génica , Glucosa/metabolismo , L-Lactato Deshidrogenasa/genética , Transportadores de Ácidos Monocarboxílicos/genética , Rhizopus/genética , Saccharomyces cerevisiae/genética , Eliminación de Secuencia , Simportadores/genética , Transgenes
6.
FEMS Yeast Res ; 18(1)2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29325040

RESUMEN

Microorganisms have been studied and used extensively to produce value-added fuels and chemicals. Yeasts, specifically Saccharomyces cerevisiae, receive industrial attention because of their well-known ability to ferment glucose and produce ethanol. Thousands of natural or genetically modified S. cerevisiae have been found in industrial environments for various purposes. These industrial strains are isolated from industrial fermentation sites, and they are considered as potential host strains for superior fermentation processes. In many cases, industrial yeast strains have higher thermotolerance, increased resistances towards fermentation inhibitors and increased glucose fermentation rates under anaerobic conditions when compared with laboratory yeast strains. Despite the advantages of industrial strains, they are often not well characterized. Through screening and phenotypic characterization of commercially available industrial yeast strains, industrial fermentation processes requiring specific environmental conditions may be able to select an ideal starting yeast strain to be further engineered. Here, we have characterized and compared 21 industrial S. cerevisiae strains under multiple conditions, including their tolerance to varying pH conditions, resistance to fermentation inhibitors, sporulation efficiency and ability to ferment lignocellulosic sugars. These data may be useful for the selection of a parental strain for specific biotechnological applications of engineered yeast.


Asunto(s)
Microbiología Industrial , Fenotipo , Saccharomyces cerevisiae/fisiología , Biotecnología , Etanol/metabolismo , Fermentación , Citometría de Flujo , Genoma Fúngico , Concentración de Iones de Hidrógeno , Ploidias , Saccharomyces cerevisiae/clasificación , Estrés Fisiológico
7.
Biotechnol Bioeng ; 115(12): 2859-2868, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30011361

RESUMEN

Simultaneous saccharification and fermentation (SSF) of cellulose via engineered Saccharomyces cerevisiae is a sustainable solution to valorize cellulose into fuels and chemicals. In this study, we demonstrate the feasibility of direct conversion of cellulose into ethanol and a biodegradable surfactant, ethyl-ß-d-glucoside, via an engineered yeast strain (i.e., strain EJ2) expressing heterologous cellodextrin transporter (CDT-1) and intracellular ß-glucosidase (GH1-1) originating from Neurospora crassa. We identified the formation of ethyl-ß-d-glucoside in SSF of cellulose by the EJ2 strain owing to transglycosylation activity of GH1-1. The EJ2 strain coproduced 0.34 ± 0.03 g ethanol/g cellulose and 0.06 ± 0.00 g ethyl-ß-d-glucoside/g cellulose at a rate of 0.30 ± 0.02 g·L-1 ·h-1 and 0.09 ± 01 g·L-1 ·h-1 , respectively, during the SSF of Avicel PH-101 cellulose, supplemented only with Celluclast 1.5 L. Herein, we report a possible coproduction of a value-added chemical (alkyl-glucosides) during SSF of cellulose exploiting the transglycosylation activity of GH1-1 in engineered S. cerevisiae. This coproduction could have a substantial effect on the overall technoeconomic feasibility of theSSF of cellulose.


Asunto(s)
Celulosa/metabolismo , Etanol/metabolismo , Glucósidos/metabolismo , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/genética , Fermentación , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glucósidos/genética , Glicosilación , Neurospora crassa/enzimología , Neurospora crassa/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/metabolismo
8.
Appl Microbiol Biotechnol ; 102(18): 8121-8133, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30027490

RESUMEN

Engineered S. cerevisiae employing the xylose reductase pathway enables efficient xylose valorization to fuels and chemicals. However, toxicity of thermochemically pretreated biomass hydrolysate on S. cerevisiae is one of the key technical challenges to upgrade biomass-derived sugars including xylose and glucose into high-value products. We investigated the effect of glycolaldehyde, one of the biomass-derived highly toxic aldehyde compounds, and its combinatorial inhibitory effect with other major fermentation inhibitors commonly found in plant hydrolysate such as methylglyoxal, 5-HMF, furfural, vanillin, and acetic acid on engineered xylose-fermenting S. cerevisiae in xylose and/or glucose media. We elucidated that glycolaldehyde and methylglyoxal are the key inhibitory short-aliphatic aldehydes on engineered xylose-fermenting S. cerevisiae in xylose-containing medium. Indeed, the degree of toxicity of these tested fermentation inhibitors varies with the sole carbon source of the medium. We demonstrate that genome integration of an extra copy of autologous GRE2 with its native promotor substantially improved the toxic tolerance of engineered xylose-fermenting S. cerevisiae to major inhibitory compounds including glycolaldehyde in the xylose-containing medium, and xylose-rich, lignocellulosic hydrolysate derived from Miscanthus giganteus, and concurrently improved the ethanol fermentation profile. Outcomes of this study will aid the development of next-generation robust S. cerevisiae strains for efficient fermentation of hexose and pentose sugars found in biomass hydrolysate.


Asunto(s)
Acetaldehído/análogos & derivados , Ingeniería Metabólica , Oxidorreductasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/enzimología , Xilosa/metabolismo , Acetaldehído/metabolismo , Biomasa , Fermentación , Glucosa/metabolismo , Oxidorreductasas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
9.
J Arthroplasty ; 33(8): 2530-2534, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29622494

RESUMEN

BACKGROUND: The direct anterior approach (DAA) for primary hip replacement has been gaining more attention and widespread use in recent years. There are a number of published studies evaluating the learning curve when a surgeon changes technique; these studies typically look at complications during the initial cases. This study examines procedure and total operating room (OR) time along with all complications for a surgeon transitioning from the posterolateral approach (PA) to DAA. METHODS: A retrospective review of a single surgeon series of 1000 initial DAA procedures. Total OR time, procedure time, and complications were collected and analyzed. One-way analysis of variance and post hoc least significant difference tests were used for statistical analysis. RESULTS: There was an initial increase in both procedure and OR times compared with the mature PA, by 34% and 30%, respectively. The procedure time became statistically equivalent to the mature PA time after the 400th DAA case, and significantly shorter after the 850th case. The total OR time became statistically equivalent after the 900th DAA case. There were 18 early (<90 days) and 18 late reoperations performed in this series with a nonsignificant trend toward femoral complications occurring early in the series. Minimum follow-up time was 2 years. CONCLUSION: There was an initial increase in both total OR time and procedure time when an experienced surgeon introduced the DAA. By the end of the series, procedure time was significantly shorter and total OR time was equivalent. Complications overall were low and femoral complications decreased with time.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Curva de Aprendizaje , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/estadística & datos numéricos , Fémur/cirugía , Humanos , Tempo Operativo , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Cirujanos/psicología , Cirujanos/estadística & datos numéricos
10.
J Ind Microbiol Biotechnol ; 44(3): 387-395, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28070721

RESUMEN

Accumulation of reduced byproducts such as glycerol and xylitol during xylose fermentation by engineered Saccharomyces cerevisiae hampers the economic production of biofuels and chemicals from cellulosic hydrolysates. In particular, engineered S. cerevisiae expressing NADPH-linked xylose reductase (XR) and NAD+-linked xylitol dehydrogenase (XDH) produces substantial amounts of the reduced byproducts under anaerobic conditions due to the cofactor difference of XR and XDH. While the additional expression of a water-forming NADH oxidase (NoxE) from Lactococcus lactis in engineered S. cerevisiae with the XR/XDH pathway led to reduced glycerol and xylitol production and increased ethanol yields from xylose, volumetric ethanol productivities by the engineered yeast decreased because of growth defects from the overexpression of noxE. In this study, we introduced noxE into an engineered yeast strain (SR8) exhibiting near-optimal xylose fermentation capacity. To overcome the growth defect caused by the overexpression of noxE, we used a high cell density inoculum for xylose fermentation by the SR8 expressing noxE. The resulting strain, SR8N, not only showed a higher ethanol yield and lower byproduct yields, but also exhibited a high ethanol productivity during xylose fermentation. As noxE overexpression elicits a negligible growth defect on glucose conditions, the beneficial effects of noxE overexpression were substantial when a mixture of glucose and xylose was used. Consumption of glucose led to rapid cell growth and therefore enhanced the subsequent xylose fermentation. As a result, the SR8N strain produced more ethanol and fewer byproducts from a mixture of glucose and xylose than the parental SR8 strain without noxE overexpression. Our results suggest that the growth defects from noxE overexpression can be overcome in the case of fermenting lignocellulose-derived sugars such as glucose and xylose.


Asunto(s)
Fermentación , Complejos Multienzimáticos/genética , NADH NADPH Oxidorreductasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Xilosa/metabolismo , Aldehído Reductasa/genética , Aldehído Reductasa/metabolismo , Biocombustibles/microbiología , D-Xilulosa Reductasa/genética , D-Xilulosa Reductasa/metabolismo , Etanol/metabolismo , Glucosa/metabolismo , Glicerol/metabolismo , Microbiología Industrial , Lignina/metabolismo , Microorganismos Modificados Genéticamente , Complejos Multienzimáticos/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , Ingeniería de Proteínas , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Xilitol/metabolismo
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