Control of Cell Migration and Inflammatory Mediators Production by CORM-2 in Osteoarthritic Synoviocytes

BackgroundOsteoarthritis (OA) is the most widespread degenerative joint disease. Inflamed synovial cells contribute to the release of inflammatory and catabolic mediators during OA leading to destruction of articular tissues. We have shown previously that CO-releasing molecules exert anti-inflammatory effects in animal models and OA chondrocytes. We have studied the ability of CORM-2 to modify the migration of human OA synoviocytes and the production of chemokines and other mediators sustaining inflammatory and catabolic processes in the OA joint.Methodology/Principal FindingsOA synoviocytes were stimulated with interleukin(IL)-1β in the absence or presence of CORM-2. Migration assay was performed using transwell chambers. Gene expression was analyzed by quantitative PCR and protein expression by Western Blot and ELISA. CORM-2 reduced the proliferation and migration of OA synoviocytes, the expression of IL-8, CCL2, CCL20, matrix metalloproteinase(MMP)-1 and MMP-3, and the production of oxidative stress. We found that CORM-2 reduced the phosphorylation of extracellular signal-regulated kinase1/2, c-Jun N-terminal kinase1/2 and to a lesser extent p38. Our results also showed that CORM-2 significantly decreased the activation of nuclear factor-κB and activator protein-1 regulating the transcription of chemokines and MMPs in OA synoviocytes.Conclusion/SignificanceA number of synoviocyte functions relevant in OA synovitis and articular degradation can be down-regulated by CORM-2. These results support the interest of this class of agents for the development of novel therapeutic strategies in inflammatory and degenerative conditions

p21 as a Transcriptional Co-Repressor of S-Phase and Mitotic Control Genes

It has been previously described that p21 functions not only as a CDK inhibitor but also as a transcriptional co-repressor in some systems. To investigate the roles of p21 in transcriptional control, we studied the gene expression changes in two human cell systems. Using a human leukemia cell line (K562) with inducible p21 expression and human primary keratinocytes with adenoviral-mediated p21 expression, we carried out microarray-based gene expression profiling. We found that p21 rapidly and strongly repressed the mRNA levels of a number of genes involved in cell cycle and mitosis. One of the most strongly down-regulated genes was CCNE2 (cyclin E2 gene). Mutational analysis in K562 cells showed that the N-terminal region of p21 is required for repression of gene expression of CCNE2 and other genes. Chromatin immunoprecipitation assays indicated that p21 was bound to human CCNE2 and other p21-repressed genes gene in the vicinity of the transcription start site. Moreover, p21 repressed human CCNE2 promoter-luciferase constructs in K562 cells. Bioinformatic analysis revealed that the CDE motif is present in most of the promoters of the p21-regulated genes. Altogether, the results suggest that p21 exerts a repressive effect on a relevant number of genes controlling S phase and mitosis. Thus, p21 activity as inhibitor of cell cycle progression would be mediated not only by the inhibition of CDKs but also by the transcriptional down-regulation of key genes

Structure of the ATP synthase catalytic complex (F(1)) from Escherichia coli in an autoinhibited conformation.

ATP synthase is a membrane-bound rotary motor enzyme that is critical for cellular energy metabolism in all kingdoms of life. Despite conservation of its basic structure and function, autoinhibition by one of its rotary stalk subunits occurs in bacteria and chloroplasts but not in mitochondria. The crystal structure of the ATP synthase catalytic complex (F(1)) from Escherichia coli described here reveals the structural basis for this inhibition. The C-terminal domain of subunit ɛ adopts a heretofore unknown, highly extended conformation that inserts deeply into the central cavity of the enzyme and engages both rotor and stator subunits in extensive contacts that are incompatible with functional rotation. As a result, the three catalytic subunits are stabilized in a set of conformations and rotational positions distinct from previous F(1) structures

Herramientas para evaluar la adecuación de la prescripción en ancianos

El envejecimiento es un proceso complejo. Con la edad se van produciendo importantes cambios fisiológicos y aumenta la incidencia de múltiples patologías orgánicas y sistémicas. A los pacientes ancianos se les prescribe un elevado número de medicamentos. Además, son los que realizan un mayor número de visitas médicas e ingresos hospitalarios. Los ancianos son el grupo poblacional con mayor grado de polimedicación. La polimedicación genera un elevado coste para el Sistema Nacional de Salud (SNS) y puede además incrementar el número de reacciones adversas medicamentosas e interacciones. La prescripción inapropiada de fármacos es un problema frecuente en los mayores, que contribuye al aumento del riesgo de reacciones adversas a medicamentos (RAM). En los últimos años, se han desarrollado varias herramientas para detectar la prescripción potencialmente inadecuada en ancianos. El objetivo de esta revisión consiste en describir dos de estas herramientas: los criterios americanos de BEERS y los criterios europeos STOPP (Screening Tool of Older Person’s Prescriptions)/ START (Screening Tool to Alert doctors to Right i.e. appropriate, indicated Treatment). Los criterios STOPP aportan el valor añadido de detectar no sólo la prescripción inadecuada por determinados fármacos, sino también por falta de prescripción de medicamentos indicados. Los criterios STOPP/START pueden convertirse en una buena herramienta para mejorar la prescripción en los pacientes mayores

Detección de prescripciones potencialmente inapropiadas en pacientes ancianos: estudio descriptivo en dos farmacias comunitarias

Introducción: Los ancianos son un grupo de pacientes heterogéneos a los que se les prescribe un número elevado de medicamentos. Esto conlleva a prescripciones potencialmente inapropiadas. Objetivo: Analizar la farmacoterapia del paciente anciano desde la farmacia comunitaria para detectar prescripciones potencialmente inapropiadas (Beers 2012 y STOPP) y prescripciones potencialmente omitidas (START), determinando su prevalencia. Metodología: Estudio descriptivo, observacional en el que se incluyeron pacientes mayores de 65 años de atención primaria que llevaban al menos un tratamiento crónico. Se verificó la idoneidad de la medicación según los criterios Beers 2012 y STOPP & START. Resultados: Se incluyeron 223 pacientes con una edad media de 75 años. En total se prescribieron 1.558 medicamentos, con una media de 7 medicamentos por paciente. El 67 % de los pacientes eran polimedicados. Con Beers 2012 se detectaron 246 prescripciones inapropiadas y el criterio que más se repitió fue el de benzodiazepinas de acción corta, intermedia y larga (36 %). Con STOPP se detectaron 146 prescripciones inapropiadas. El criterio más frecuente fue IBP a dosis plenas durante más de 8 semanas (14 %). Con START se detectaron 103 prescripciones potencialmente omitidas, siendo antiagregantes plaquetarios en diabetes mellitus la más frecuente (11,6 %). Conclusiones: Los criterios Beers 2012 y STOPP-START, suponen una herramienta de utilidad en la detección de los posibles problemas relacionados con los medicamentos en una farmacia comunitaria. En ningún caso suponen una prohibición en la utilización de dichos medicamentos, puesto que su prescripción dependerá de las características del paciente en concreto y del juicio clínico del médico prescriptor

Fluoroquinolone Efflux in Streptococcus suis Is Mediated by SatAB and Not by SmrA.

Streptococcus suis is an emerging zoonotic pathogen. With the lack of an effective vaccine, antibiotics remain the main tool to fight infections caused by this pathogen. We have previously observed a reserpine-sensitive fluoroquinolone (FQ) efflux phenotype in this species. Here, SatAB and SmrA, two pumps belonging to the ATP binding cassette (ABC) and the major facilitator superfamily (MFS), respectively, have been analyzed in the fluoroquinolone-resistant clinical isolate BB1013. Genes encoding these pumps were overexpressed either constitutively or in the presence of ciprofloxacin in this strain. These genes could not be cloned in plasmids in Escherichia coli despite strong expression repression. Finally, site-directed insertion of smrA and satAB in the amy locus of the Bacillus subtilis chromosome using ligated PCR amplicons allowed for the functional expression and study of both pumps. Results showed that SatAB is a narrow-spectrum fluoroquinolone exporter (norfloxacin and ciprofloxacin), susceptible to reserpine, whereas SmrA was not involved in fluoroquinolone resistance. Chromosomal integration in Bacillus is a novel method for studying efflux pumps from Gram-positive bacteria, which enabled us to demonstrate the possible role of SatAB, and not SmrA, in fluoroquinolone efflux in S. suis

Transcriptional analysis of tendril and inflorescence development in grapevine (Vitis vinifera L.)

In grapevine (Vitis vinifera L.), the lateral meristem can give rise to either tendrils or inflorescences which are determined organs. To get insights into the processes of tendril and inflorescence development, we characterized the transcriptional variation taking place in both organs. The results of the global transcriptional analyses along tendril and inflorescence development suggested that these two homologous organs initially share a common transcriptional program related to cell proliferation and growth functions. In later developmental stages they showed organ specific gene expression programs related to the particular differentiation processes taking place in each organ. In this way, tendrils showed higher transcription of genes related to photosynthesis, hormone signaling and secondary metabolism than inflorescences, while inflorescences displayed higher transcriptional activity for genes encoding transcription factors, mainly those belonging to the MADS-box gene family. The expression profiles of selected transcription factors related with inflorescence and flower meristem identity and with flower organogenesis were generally conserved with respect to their homologs in model species. Regarding tendrils, it was interesting to find that genes related with reproductive development in other species were also recruited for grapevine tendril development. These results suggest a role for those genes in the regulation of basic cellular mechanisms common to both developmental processes. Copyright: © 2014 Daz-Riquelme et al