RESUMEN
BACKGROUND: Six monthly courses of mitoxantrone were approved in France in 2003 for patients with highly active multiple sclerosis (MS). OBJECTIVE: To report the 10-year clinical follow-up and safety of mitoxantrone as an induction drug followed by maintenance therapy in patients with early highly active relapsing-remitting MS (RRMS) and an Expanded Disability Status Scale (EDSS) score<4, 12months prior to mitoxantrone initiation. METHODS: In total, 100 consecutive patients with highly active RRMS from the Rennes EDMUS database received monthly mitoxantrone 20mg combined with methylprednisolone 1g for 3 (n=75) or 6months (n=25) followed by first-line disease-modifying drug (DMD). The 10-year clinical impact was studied through clinical activity, DMD exposure, and adverse events. RESULTS: Twenty-four percent were relapse-free over 10years and the mean annual number of relapses was 0.2 at 10years. The mean EDSS score remained significantly improved for up to 10years, changing from 3.5 at mitoxantrone initiation to 2.7 at 10years. The probability of disability worsening and improvement from mitoxantrone initiation to 10years were respectively 27% and 58%, and 13% converted to secondary progressive MS. Patients only remained untreated or treated with a first-line maintenance DMD for 6.5years in average. In our cohort, mitoxantrone was generally safe. No leukemia was observed and six patients developed neoplasms, including 4 solid cancers. CONCLUSION: Monthly mitoxantrone for 3 or 6months, followed by maintenance first-line treatment, may be an attractive therapeutic option for patients with early highly active RRMS, particularly in low-income countries.
Asunto(s)
Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Estudios de Seguimiento , Humanos , Mitoxantrona/farmacología , Mitoxantrona/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple Crónica Progresiva/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , RecurrenciaRESUMEN
Duchenne Muscular Dystrophy (DMD) is a lethal muscle disorder, caused by mutations in the DMD gene and affects approximately 1:5000-6000 male births. In this report, we identified dysregulation of members of the Dlk1-Dio3 miRNA cluster in muscle biopsies of the GRMD dog model. Of these, we selected miR-379 for a detailed investigation because its expression is high in the muscle, and is known to be responsive to glucocorticoid, a class of anti-inflammatory drugs commonly used in DMD patients. Bioinformatics analysis predicts that miR-379 targets EIF4G2, a translational factor, which is involved in the control of mitochondrial metabolic maturation. We confirmed in myoblasts that EIF4G2 is a direct target of miR-379, and identified the DAPIT mitochondrial protein as a translational target of EIF4G2. Knocking down DAPIT in skeletal myotubes resulted in reduced ATP synthesis and myogenic differentiation. We also demonstrated that this pathway is GC-responsive since treating mice with dexamethasone resulted in reduced muscle expression of miR-379 and increased expression of EIF4G2 and DAPIT. Furthermore, miR-379 seric level, which is also elevated in the plasma of DMD patients in comparison with age-matched controls, is reduced by GC treatment. Thus, this newly identified pathway may link GC treatment to a mitochondrial response in DMD.
Asunto(s)
Glucocorticoides/uso terapéutico , MicroARNs/metabolismo , Mitocondrias/metabolismo , Distrofia Muscular de Duchenne/tratamiento farmacológico , Adenosina Trifosfato/metabolismo , Animales , Sitios de Unión , Dexametasona/farmacología , Modelos Animales de Enfermedad , Perros , Factor 4G Eucariótico de Iniciación/química , Factor 4G Eucariótico de Iniciación/genética , Factor 4G Eucariótico de Iniciación/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , MicroARNs/química , ATPasas de Translocación de Protón Mitocondriales/antagonistas & inhibidores , ATPasas de Translocación de Protón Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/genética , Mioblastos Esqueléticos/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismoRESUMEN
Amentoflavone hexaacetate (AmAc) was synthesized from natural amentoflavone (Am), a biflavonoid extracted from Viburnum lantana L. Am does not inhibit aggregation of intact platelets up to a concentration of 100 microM but inhibits human platelet cAMP phosphodiesterase (IC50 = 22.0 microM). AmAc is a potent inhibitor of the aggregation of washed human platelets induced by ADP (IC50 = 2.3 microM) or collagen (IC50 = 4.7 microM). AmAc inhibits crude (IC50 = 8.6 microM) or partially purified (IC50 = 42.2 microM) human platelet cAMP phosphodiesterase. In the presence of prostaglandin E1, AmAc (10 microM) induces a 3.7-fold increase in total platelet cAMP. The characteristics of this action suggest a role for cAMP in the mechanism of action of AmAc. The incubation of AmAc with intact platelets for 5 min is necessary for its activity.
Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Biflavonoides , Plaquetas/enzimología , AMP Cíclico/sangre , Flavonoides/farmacología , Agregación Plaquetaria/efectos de los fármacos , 3',5'-AMP Cíclico Fosfodiesterasas/sangre , Adenosina Difosfato/farmacología , Plaquetas/metabolismo , Colágeno/fisiología , HumanosRESUMEN
Cyclic nucleotide phosphodiesterase inhibitors (HL-725, RO 15-2041, cilostamide, quercetin and MY-5445) potently inhibit human platelet aggregation induced by ADP. In parallel, PDE inhibitors inhibit the increase in cytoplasmic free Ca2+ evoked by ADP, as measured with the fluorescent probe quin 2. The inhibition of ADP-induced aggregation and rise in [Ca2+]i is potentiated by PGE1 which stimulates adenylate cyclase and is inhibited by adrenaline which inhibits adenylate cyclase. PDE inhibitors increase human platelet cAMP levels in the presence of low concentrations of PGE1. It is suggested that PDE inhibitors prevent platelet aggregation by raising cAMP levels and by subsequent inhibition of cytoplasmic free Ca2+ mobilization.
Asunto(s)
2',3'-Nucleótido Cíclico Fosfodiesterasas/antagonistas & inhibidores , Plaquetas/efectos de los fármacos , Calcio/metabolismo , AMP Cíclico/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Quinolonas , Tetrahidroisoquinolinas , Alprostadil/farmacología , Aminoquinolinas/farmacología , Plaquetas/enzimología , Citoplasma/metabolismo , Humanos , Isoquinolinas/farmacología , Ftalazinas/farmacología , Quercetina/farmacología , Quinazolinas/farmacología , Quinolinas/farmacologíaRESUMEN
Quadrigemine B, quadrigemine A, isopsychotridine C and psychotridine, isolated from PSYCHOTRIA FORSTERIANA, are potent inhibitors of the aggregation of washed human platelets induced by ADP, collagen or thrombin. The four compounds are active in the 1-10 microM range. The quadrigemine-type alkaloids do not increase the level of platelet cyclic AMP, either alone or in the presence of 20 nM prostaglandin E, (PGE (1)), an activator of adenylate cyclase. The characteristics of the pharmacological action of these compounds suggest that they act at a later stage in platelet activation, possibly through an interaction with cytoskeletal proteins.
RESUMEN
In recent years, outstanding molecular approaches have been used to investigate genes and functions involved in plant-microbe endosymbioses. In this review, we outline the use of proteomic analysis, based on two-dimensional electrophoresis and mass spectrometry, to characterize symbiosis-related proteins. During the last decade, proteomics succeeded in identifying about 400 proteins associated with the development and functioning of both mycorrhizal and rhizobial symbioses. Further progress in prefractionation procedures is expected to allow the detection of symbiotic proteins showing low abundance or being present in certain cell compartments.
Asunto(s)
Proteínas Fúngicas/genética , Micorrizas/genética , Proteínas de Plantas/genética , Proteómica , Simbiosis/genética , Espectrometría de Masas , Raíces de Plantas/microbiología , Microbiología del SueloRESUMEN
Colonization of Pisum sativum L. cv. Frisson roots with the arbuscular mycorrhizal fungus Glomus mosseae leads to the induction of four acidic symbiosis-related chitinase (SR-chi) isoforms (EC 3.2.1.14). These isoforms were characterized as 30-kDa proteins with isoelectric points ranging between 5.2 and 5.85. One of these SR-chis was purified by affinity and anion-exchange chromatographies, and isoelectric focusing electrophoresis. The sequences of four internal peptides were obtained. They showed high homology to a class-I chitinase isoform from pea shoots. Parts of the conserved regions of class-I chitinases were found in this SR-chi. This result strongly supports the argument that this SR-chi isoform is of plant origin. The functional role of the SR-chis in arbuscular mycorrhizal symbiosis is discussed.