Orientin inhibits the progression of fibroblast-like synovial cells in rheumatoid arthritis by regulating MAPK-signaling pathway

Background Natural compounds are found to play an essential role in diverse inflammatory diseases, including rheumatoid arthritis (RA). Orientin, a flavonoid compound, is closely related to diverse pathological processes. Nevertheless, the role of orientin in RA is still unknown. Methods The cell viability was tested through cell counting kit 8 (CCK-8) assay, and the number of cell colonies was calculated via colony formation assay. In addition, flow cytometry assay was employed to detect apoptosis rate in human RA fibroblast-like synoviocytes (RA-FLS). Besides, Transwell assay was introduced to determine cell migratory and invasive abilities. Moreover, the level of cytokines (IL-8, IL-1β, and IL-6) was estimated with quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent serologic assay. Furthermore, western blotting analysis was used to test the protein levels of cleaved-caspase-3, Bax, BCL-2, matrix metalloproteinase (MMP)-2, MMP-9, phosphorylated c-Jun N-terminal kinase, p-P38, and phospho-extracellular signal-related kinase. Results Orientin inhibited cell viability, migration as well as invasion in a concentration- dependent manner in human RA-FLS. Additionally, treatment of orientin facilitated apoptosis and decreased the secretion of cytokines induced by tumor necrosis factor alpha (TNF-α) in human RA-FLS. Moreover, orientin inactivated mitogen-activated protein kinase (MAPK)-related signaling pathway, notably in human RA-FLS. Conclusion These findings confirmed that orientin inhibited human RA-FLS development and decreased TNF-α-induced inflammatory factors, at least partly, by modulating MAPK-signaling pathway, which implied that orientin might be an effective agent for treating RA (AU)

Knockdown of CXCL3-inhibited apoptosis and inflammation in lipopolysaccharide-treated BEAS-2B and HPAEC through inactivating MAPKs pathway

Background: CXCL3 (C-X-C motif chemokine ligand 3) is a member of chemokines family, which binds to the receptor to recruit neutrophils to lungs, thus participating in the pathogenesis of asthmatic lung. The role of CXCL3 in sepsis-induced acute lung injury is investigated here.Methods: Human lung epithelial cell line (BEAS-2B) and human pulmonary artery endothelial cell line (HPAEC) were treated with lipopolysaccharides (LPS). MTT and flow cytometry were performed to detect cell viability and apoptosis, respectively. Enzyme-linked immunosorbent assay (ELISA) and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to assess the levels of inflammatory factors.Results: Treatment with LPS resulted in the decrease of cell viability in BEAS-2B and HPAEC. CXCL3 was particularly upregulated in LPS-treated BEAS-2B and HPAE cells. Knockdown of CXCL3 enhanced viability and suppressed apoptosis i006E LPS-treated BEAS-2B and HPAE cells. Knockdown of CXCL3 also upregulated TNF-α, I L-1β, and IL-18 in LPS-treated BEAS-2B and HPAE cells. Moreover, knockdown of CXCL3 suppressed the activation of mitogen-activated protein kinases (MAPKs) signaling in LPS-treated BEAS-2B and HPAE cells through downregulation of p-ERK1/2, p-p38, and p-JNK. On the other hand, overexpression of CXCL3 caused completely opposite results in LPS-treated BEAS-2B and HPAE cells.Conclusion: Knockdown of CXCL3 exerted antiapoptotic and anti-inflammatory effects against LPS-treated BEAS-2B and HPAE cells, at least partially, through inactivation of MAPKs signaling, suggesting a potential strategy for the intervention of sepsis-induced acute lung injury (AU)

Retinopatía asociada a inhibidor de la proteinquinasa de activación mitogénica (MEKAR). A propósito de un caso / Mitogen-activated protein kinase inhibitor-associated retinopathy (MEKAR). A clinical case

Los inhibidores de la proteína quinasa de activación mitogénica (MEK) son fármacos utilizados para el tratamiento de neoplasias tales como el melanoma metastásico. Su introducción ha mejorado el pronóstico de estas enfermedades, pero su uso no está exento de complicaciones oculares. Se ha descrito una retinopatía asociada a estos fármacos (MEKAR) consistente en la aparición de desprendimientos neurosensoriales (DNS), generalmente bilaterales y múltiples similares a los que aparecen en la coriorretinopatía serosa central (CSC). En la mayoría de los casos la tomografía de coherencia óptica es suficiente para diferenciar esta entidad de una CSC. Presentamos el caso de una paciente de 55 años que, en este contexto, desarrolló DNS bilaterales que asociaron disminución de agudeza visual y que se resolvieron cuando se suspendió la terapia por progresión tumoral (AU)

Mitogen-activated protein kinase kinase (MEK) inhibitors have significantly improved the prognosis of various types of cancer such as metastatic melanoma. However, their use is usually associated with ocular side effects. A retinopathy associated with these agents (MEKAR) has been described, consisting of the development of neurosensory detachments, generally bilateral and multiple, similar to those that appear in the central serous chorioretinopathy (CSC). Generally, optical coherence tomography allows us to differentiate the two conditions. We present the case of a 55-year-old woman in treatment with a MEK inhibitor, who developed bilateral neurosensory detachments and blurred vision, which resolved with the discontinuance of the treatment due to tumour progression (AU)

Effects of PIM3 in prognosis of colon cancer

Purpose PIM kinase is called proto-oncogene, but there are less research on PIM family in colon cancer. This study was designed to explore the prognosis of PIM3 in colon cancer. Methods In this study, we downloaded RNA-seq and clinical information of colon cancer from the Gene Expression Omnibus (GEO) database. Kaplan–Meier method was used for analyzing the impact of PIM3 on the survival of patients with colon cancer. Single-factor and multi-factor cox regression analysis were used for verifying the prognostic value of PIM3. Spearman correlation analysis was used for screening PIM3 related genes. Functional enrichment analysis was used for analyzing the biological functions and pathways in which PIM3 related genes may be involved. STRING online tools were used for building a co-expression network. Cytoscape was used for co-expression network visualization. Results Compared with the low expression group, the patients in the PIM3 high expression group lived longer time. Single-factor and multi-factor cox regression analysis indicated that PIM3 was an independent prognostic factor for colon cancer. Sixty-two PIM3 related genes were screened, and GO and KEGG enrichment analyses suggested that PIM3 related genes might be involved in the MAPK and WNT pathways. The co-expression network showed a strong correlation between PIM3 and MLKL, MYL5, PPP3R1 and other genes. Conclusions PIM3 is an independent prognostic factor of colon cancer and may be a target for the diagnosis and treatment of colon cancer (AU)

Síndrome de Noonan: actualización genética, clínica y de opciones terapéuticas / Noonan syndrome: genetic and clinical update and treatment options

El síndrome de Noonan (SN) es una enfermedad de origen genético relativamente frecuente cuyas manifestaciones fundamentales son la talla baja, la cardiopatía congénita y un fenotipo facial característico. La causa del síndrome de Noonan y de otras enfermedades clínicamente solapadas como el síndrome de Noonan con lentiginosis múltiple (anteriormente llamado síndrome LEOPARD), el cardiofaciocutáneo o el síndrome de Costello, son mutaciones en genes que codifican para proteínas de la vía de señalización de las RAS-MAPKinasas. Debido a este sustrato común este grupo de enfermedades son denominadas colectivamente «rasopatías». A pesar de los avances genéticos de las últimas décadas, cerca de 20% de pacientes no tienen causa genética identificada, y el diagnóstico sigue siendo clínico. El síndrome de Noonan se caracteriza por una alta heterogeneidad clínica y genética, con afectación variable, y cambiante con la edad, de múltiples órganos y sistemas. Debido a esta variabilidad es fundamental que los médicos involucrados en su cuidado estén familiarizados con sus manifestaciones y conozcan las recomendaciones de seguimiento, incluido el seguimiento del crecimiento y desarrollo. Hasta la fecha los escasos datos de crecimiento con GH a talla adulta dan resultados de ganancia de talla moderados, semejantes a los obtenidos en el síndrome de Turner. La hiperactivación de la vía RAS-MAPK como base común de esta familia de enfermedades brinda una oportunidad única para el desarrollo de tratamientos dirigidos a la etiología de estos trastornos

Noonan syndrome (NS) is a relatively common genetic condition characterised by short stature, congenital heart defects, and distinctive facial features. NS and other clinically overlapping conditions such as NS with multiple lentigines (formerly called LEOPARD syndrome), cardiofaciocutaneous syndrome, or Costello syndrome, are caused by mutations in genes encoding proteins of the RAS-MAPKinases pathway. Because of this shared mechanism, these conditions have been collectively termed «RASopathies». Despite the recent advances in molecular genetics, nearly 20% of patients still lack a genetic cause, and diagnosis is still made mainly on clinical grounds. NS is a clinically and genetically heterogeneous condition, with variable expressivity and a changing phenotype with age, and affects multiple organs and systems. Therefore, it is essential that physicians involved in the care of these patients are familiarised with their manifestations and the management recommendations, including management of growth and development. Data on growth hormone treatment efficacy are sparse, and show a modest response in height gains, similar to that observed in Turner syndrome. The role of RAS/MAPK hyper-activation in the pathophysiology of this group of disorders offers a unique opportunity for the development of targeted approaches

Placas crateriformes en un paciente con enfermedad renal crónica. Un caso de colagenosis perforante reactiva adquirida / Crateriform plaques in a patient with end-stage renal disease. The case of an acquired reactive perforating colagenosis

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Inhibiting ERK/Mnk/eIF4E broadly sensitizes ovarian cancer response to chemotherapy

Purpose. To investigate whether ERK/MNK/eIF4E contributes chemoresistance in ovarian cancer. Methods. The phosphorylated levels of Erk, Mnk, and eIF4E were systematically analyzed in ovarian cancer patients before and after chemotherapy, and ovarian cancer cells exposed to short- and long-term chemo-agent treatment. The roles of Erk/Mnk/eIF4E were investigated using pharmacological and genetic approaches. Results. Increased phosphorylation levels of ERK, Mnk1, and eIF4E were observed in ovarian cancer cell exposed to chemotherapeutic agents, and paclitaxel-resistant SK-OV-3-r cells, and is a common response of ovarian cancer patients undergoing chemotherapy. MEK inhibitor U0126 inhibits basal and chemodrug-induced phosphorylation of ERK as well as Mnk1 and eIF4E, suggesting that Mnk1/eIF4E are the downstream signaling of ERK pathway and chemotherapy agents activate ERK/MNK/eIF4E in a MEK-dependent manner. eIF4E overexpression promotes ovarian cancer cell growth without affecting migration. In addition, ovarian cancer cells with eIF4E overexpression are more resistant to chemotherapeutic agents in aspect of growth inhibition and apoptosis induction compared to control cells. In contrast, eIF4E depletion augments chemotherapeutic agents’ effect in ovarian cancer cells. These demonstrate that eIF4E play roles in growth and chemoresistance in ovarian cancer. MEK inhibitor U0126 also significantly enhances chemotherapeutic agents’ inhibitory effects. Conclusions. Our work shows that ERK/Mnk/eIF4E activation is critically involved in ovarian cancer chemoresistance and inhibiting ERK/Mnk/eIF4E broadly sensitizes ovarian cancer response to chemotherapy (AU)

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Retinopatía MEK. Casos clínicos / MEK Retinopathy. Clinical case reports

CASOS CLÍNICOS: Se presentan 3 casos clínicos de retinopatía MEK asociados al uso de la combinación de cobimetinib y vemurafenib, caracterizados por la alteración del epitelio pigmentario de la retina y desprendimiento neurosensorial. Dos de ellos conservaron la visión de la unidad, el tercero desarrolló un gran desprendimiento neurosensorial bilateral con una agudeza visual final de 0,6 en el ojo derecho y de 0,1 en el izquierdo. DISCUSIÓN: Las nuevas estrategias terapéuticas frente al melanoma cutáneo metastásico condicionan la aparición de alteraciones del epitelio pigmentario de la retina con desprendimientos serosos, lo que obliga a una vigilancia estrecha bajo tomografía de coherencia óptica macular

CASE REPORTS: Three clinical cases are presented of MEK retinopathy associated with the combination of cobimetinib and vemurafenib characterised by alteration of the retinal pigment epithelium and neurosensory detachment. Two of the cases conserved the vision of the unit, and the third developed a large bilateral neurosensory detachment with final visual acuity of 0.6 for the right eye and 0.1 for the left one. DISCUSSION: The new therapeutic strategies against metastatic cutaneous melanoma condition the appearance of alterations of the pigmentary epithelium of the retina with serous detachments, leading to close monitoring with macular optical coherence tomography

Functional analysis of the MAPK pathways in fungi / Análisis funcional de las vías MAPK de los hongos

The Mitogen-Activated Protein Kinase (MAPK) signaling pathways constitute one of the most important and evolutionarily conserved mechanisms for the perception of extracellular information in all the eukaryotic organisms. The MAPK pathways are involved in the transfer to the cell of the information perceived from extracellular stimuli, with the final outcome of activation of different transcription factors that regulate gene expression in response to them. In all species of fungi, the MAPK pathways have important roles in their physiology and development; e.g. cell cycle control, mating, morphogenesis, response to different stresses, resistance to UV radiation and to temperature changes, cell wall assembly and integrity, degradation of cellular organelles, virulence, cell-cell signaling, fungus-plant interaction, and response to damage-associated molecular patterns (DAMPs). Considering the importance of the phylogenetically conserved MAPK pathways in fungi, an updated review of the knowledge on them is discussed in this article. This information reveals their importance, their distribution in fungal species evolutionarily distant and with different lifestyles, their organization and function, and the interactions occurring between different MAPK pathways, and with other signaling pathways, for the regulation of the most complex cellular processes (AU)

Las vías de señalización de la proteína-cinasa activada por mitógenos (abreviadas como MAPK por sus siglas en inglés) son uno de los mecanismos más importantes y evolutivamente conservados para la percepción de información extracelular en organismos eucarióticos. Las vías MAPK están involucradas en la transferencia a la célula de la información recibida de estímulos extracelulares, que ofrecen como resultado final la activación de diferentes factores de transcripción que regulan la expresión de genes en respuesta a aquellos. En todas las especies de hongos, las vías MAPK tienen importantes funciones en su fisiología y desarrollo como, por ejemplo, el control del ciclo celular, el apareamiento, la morfogénesis, la respuesta a diferentes tipos de estrés, la resistencia a la luz UV y a los cambios de temperatura, la formación e integridad de la pared celular, la degradación de los orgánulos, la virulencia, la señalización célula-célula, la interacción hongo-planta y la respuesta a patrones moleculares asociados con el daño (abreviado como DAMP, por sus siglas en inglés). Dada la importancia de las vías MAPK en hongos, en esta revisión se discute el conocimiento adquirido más recientemente sobre ellas. Esta información revela su importancia, su distribución en especies de hongos evolutivamente distantes y con estilos de vida diferentes, su organización y función, y las interacciones que ocurren entre diferentes vías MAPK, y entre estas y otras vías de señalización que regulan los procesos celulares más complejos (AU)

Cutaneous Adverse Events of New Anti-melanoma Therapies: Classification and Management / Efectos cutáneos adversos de los nuevos tratamientos para melanoma: Clasificación y Tratamiento

Over the past decade, targeted therapies such as BRAF inhibitors, MEK inhibitors and immunotherapies such as anti-CTLA4 and anti-PD1 antibodies have emerged as novel treatments of advanced melanoma. Along with increased use of these therapies, a range of cutaneous adverse events have also emerged, varying from more serious and frequent cutaneous squamous cell carcinoma to mere cosmetic changes such as curly hair or rare severe toxic epidermal necrolysis. Early detection and management of these cutaneous adverse events will aid patients to receive accurate treatment, avoid unnecessary discontinuation of anti-tumour treatment and improve the patient’s overall quality of life. This review will describe various cutaneous adverse events of anti-melanoma therapies and its management

En la última década han aparecido nuevos tratamientos para el melanoma avanzado, como las terapias contra dianas como los inhibidores de BRAF o MEK, y las inmunoterapias como los anticuerpos contra CTLA-4 y PD1. Debido al uso cada vez más frecuente de estos tratamientos también han aparecido diversos efectos secundarios cutáneos, que van desde efectos graves y frecuentes como el desarrollo de carcinomas espinocelulares, a cambios cosméticos como el pelo rizado, o casos infrecuentes y graves de necrosis epidérmica tóxica. La detección y el tratamiento temprano de estos efectos adversos ayudará a los pacientes a recibir mejor tratamiento, a evitar el cese de la terapia antitumoral y a mejorar su calidad de vida. En esta revisión describiremos los efectos cutáneos adversos de los nuevos tratamientos contra el melanoma y su tratamiento

Molecular mechanism mediating cytotoxic activity of axitinib in sunitinib-resistant human renal cell carcinoma cells

Purpose: This study aimed to clarify the molecular mechanism mediating the cytotoxicity of axitinib, a selective inhibitor of the vascular endothelial growth factor receptor (VEGFR), in sunitinib-resistant renal cell carcinoma (RCC). Methods: In our previous study (Sakai et al. in BJU Int 112:E211-E220, 2013), a human RCC cell line, ACHN, resistant to sunitinib (ACHN/R), was developed from a parental cell line (ACHN/P). Differences in molecular phenotypes following treatment with sunitinib or axitinib between these two cell lines were compared. Results: ACHN/R showed an approximately fivefold higher IC50 of sunitinib than ACHN/P; however, there was no significant difference in the sensitivity to axitinib between these two cell lines. In ACHN/R, despite the lack of a difference in the phosphorylated (p)-Akt or STAT-3 expression between treatment with sunitinib and axitinib, the expression of p-p44/42 mitogen-activated protein kinase (MAPK) and p-VEGFR-2 after treatment with axitinib was markedly down-regulated compared with those after treatment with sunitinib. Furthermore, additional treatment of ACHN/R with an inhibitor of MAPK kinase significantly enhanced the cytotoxic activity of sunitinib, but not that of axitinib. In vivo growth of ACHN/R in nude mice after treatment with axitinib was significantly inhibited compared with that following treatment with sunitinib, accompanying the marked inhibition of angiogenesis. Conclusions Antitumor activity of axitinib in RCC cells even after the acquisition of resistance to sunitinib could be explained, at least in part, by the inactivation of p44/42 MAPK and VEGFR-2, which were persistently phosphorylated in sunitinib-resistant RCC cells under treatment with sunitinib (AU)

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Neuroprotective effect of schizandrin A on oxygen and glucose deprivation/reperfusion-induced cell injury in primary culture of rat cortical neurons

Brain ischemia appears to be associated with innate immunity. Recent reports showed that C3a and C5a, as potent targets, might protect against ischemia induced cell death. In traditional Chinese medicine, the fruit of Schizandra chinesis Baill (Fructus schizandrae) has been widely used as a tonic. In the present study, we sought to evaluate the neuroprotective effects of schizandrin A, a composition of S. chinesis Baill, against oxygen and glucose deprivation followed by reperfusion (OGD/R)-induced cell death in primary culture of rat cortical neurons, and to test whether C3a and C5a affected cortical neuron recovery from ischemic injury after schizandrin A treatment. The results showed that schizandrin A significantly reduced cell apoptosis and necrosis, increased cell survival, and decreased intracellular calcium concentration ([Ca2+]i) and lactate dehydrogenase (LDH) release in primary culture of rat cortical neurons after OGD/R. Mechanism studies suggested that the modulation of extracellular-regulated kinase (ERK), c-Jun NH2-terminal kinases (JNK), and p38, as well as caspase-3 activity played an important role on the progress of neuronal apoptosis. C5aR participated in the neuroprotective effect of schizandrin A in primary culture of rat cortical neurons after OGD/R. Our findings suggested that schizandrin A might act as a candidate therapeutic target drug used for brain ischemia and related diseases

Proteincinasa activada por AMP y enfermedades neurológicas / Protein kinase C activated by AMP and neurological diseases

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Serine protease inhibitor gabexate mesilate attenuates american cockroach-induced bronchial damage and inflammatory cytokine release

Background and objective: Allergic airway diseases are not only a TH2-mediated chronic airway inflammation, but also a condition of epithelial barrier defects and dysfunction. Allergens with protease activities are known factors that initiate respiratory epithelial damage. Cockroach allergy is the second leading cause of allergic respiratory airway diseases in Taiwan, and cockroach allergens have strong serine protease activity. This study aimed to determine the protective effect of the direct local administration of gabexate mesilate (GM) on American cockroach allergen (CraA)-induced human bronchial epithelial cell inflammation. Methods: BEAS-2B cells, from the human bronchial epithelial cell line, were stimulated with CraA or co-cultured with different doses of GM. Cellular morphologic changes were observed by microscopy and changes in chemokine mRNA expression and protein levels were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and ELISA. Effects of specific inhibitors of ERK1/2 (U0126), JNK (SP600125), and p38 MAPK (SB203580) on CraA-induced chemokine mRNA expression were also tested by RT-PCR. Results: GM prevented CraA-induced bronchial epithelial cell detachment and morphological changes. It had superior and more extensive suppression effects than specific target MAPK inhibitors in CraA-induced mRNA expression of IL-8, monocyte chemotactic protein (MCP) 1, chemokine (C-C motif) ligand 20, and granulocyte-macrophage colony-stimulating factor from the cells in a dose-dependent manner. CraA-induced IL-8 and MCP-1 protein production from BEAS-2B cells was also attenuated by GM. Conclusions: The serine protease inhibitor GM has local protective effects against CraA-induced bronchial epithelial inflammation. The development of an inhaled or intranasal protease inhibitor may be a potential strategy for the treatment of allergic airway diseases induced by allergens with protease activities (AU)

Antecedentes y objetivo: Las enfermedades alergicas de las vias respiratorias no son solo fruto de una inflamacion cronica de las vias respiratorias mediada por Th2, sino que tambien se encuentran defectos fisicos y funcionales de la barrera epitelial. En este sentido, es conocido el papel de los alergenos con actividad proteasa que son los factores conocidos de inicio del dano epitelial respiratorio. La alergia a las cucarachas es la segunda causa principal de enfermedades alergicas de las vias respiratorias en Taiwan y estos alergenos poseen una potente actividad serin-proteasa. Este estudio tuvo como objetivo determinar el efecto protector del mesilato de gabexate (GM) contra la inflamacion inducida por la administracion local directa de alergenos de la cucaracha americana (CRAA), sobre las celulas epiteliales bronquiales humanas. Metodos: Se empleo la linea de celulas epiteliales bronquiales, celulas BEAS-2B, las cuales se estimularon con CRAA o fueron co-cultivadas con diferentes dosis de GM. Se analizaron los cambios morfologicos celulares por microscopia y los cambios en la expresion de ARNm de diferentes quimiocinas, asi como los niveles de proteina. Se utilizaron metodos semi-cuantitativos de RT-PCR y ELISA. Los efectos de inhibidores especificos de ERK1/2 (U0126), JNK (SP600125), y p38 MAPK (SB203580) en las expresion de ARNm de quimiocinas inducidas por CRAA, tambien se ensayaron por RT-PCR. Resultados: El mesilato de gabexate impidio el desprendimiento de las celulas epiteliales y los cambios morfologicos inducidos con CRAA a nivel bronquial. Sus efectos supresores fueron mas potentes y prolongados que los obtenidos con inhibidores especificos de MAPK sobre la expresion del ARNm de IL-8, MCP-1, CCL20 y GMSF en una forma dosis-dependiente. La produccion proteica de IL-8 y MCP-1 de las celulas BEAS-2B tambien fue menor cuando se anadio GM. Conclusiones: El mesilato de gabexate, inhibidor serin-proteasa , tiene efectos protectores locales contra la inflamacion bronquial epitelial inducida por la cucaracha americana. El desarrollo de un inhibidor de la proteasa, por via inhalada o intranasal, puede ser una estrategia potencial para el tratamiento de enfermedades de las vias respiratorias alergicas inducidas por alergenos con actividad proteasa (AU)

A high-fat diet decreases AMPK activity in multiple tissues in the absence of hyperglycemia or systemic inflammation in rats

Consumption of a high-fat diet (HFD) in experimental animal models initiates a series of molecular events and outcomes, including insulin resistance and obesity, that mimic the metabolic syndrome in humans. The relationship among, and order of, the molecular events linking a diet high in fat to pathologies is often unclear. In the present study, we provide several novel insights into the relationship between a HFD and AMP-activated protein kinase (AMPK), a key regulator of cellular metabolism and whole-body energy balance. HFD substantially decreased the activities of both isoforms of AMPK in white adipose tissue, heart, and liver. These decreases in AMPK activity occurred in the absence of decreased AMPK transcription, systemic inflammation, hyperglycemia, or elevated levels of free fatty acids. The HFD-induced decrease in AMPK activity was associated with systemic insulin resistance and hyperleptinemia. In blood, >98 % of AMPK activity was localized in agranulocytes as the á1 isoform. In contrast to the solid tissues studied, AMPK activities were not altered by HFD in granulocytes or agranulocytes. We conclude that HFD-induced obesity causes a broad, non-tissue, or isoform-specific lowering of AMPK activity. Given the central position AMPK plays in whole-body energy balance, this decreased AMPK activity may play a previously unrecognized role in obesity and its associated pathologies (AU)

Evaluación endoscópica y hallazgos histológicos en la enfermedad de injerto contra huésped / Endoscopic evaluation and histological findings in graft-versus-host disease

Introducción: el tracto gastrointestinal es la diana principal de afectación en la enfermedad de injerto contra huésped (EICH). Su diagnóstico se basa en los hallazgos endoscópicos e histológicos. Material y métodos: hemos realizado un estudio retrospectivo, desde el 1 de enero de 1990 hasta el 30 de diciembre de 2008, de 338 endoscopias digestivas altas realizadas a 197 pacientes sometidos a trasplante alogénico de células hematopoyéticas con sospecha de EICH gastrointestinal. Resultados: los hallazgos endoscópicos tienen una sensibilidad (S) del 34%, especificidad (E) del 65%, valor predictivo positivo (VPP) del 73% y valor predictivo negativo (VPN) del 48% para el diagnóstico de EICH. El estudio histológico de las biopsias tiene una S del 85,6%, E del 34,6%, VPP del 64,2% y VPN del 63,7%. El grado histológico se correlacionó con el grado clínico en la EICH aguda (p = 0,0018). Conclusión: la endoscopia digestiva alta es útil para el diagnóstico de EICH, ya que permite la toma de biopsias que finalmente pueden llevar al diagnóstico, pero con una rentabilidad limitada ya que los hallazgos histológicos tienen una sensibilidad y especificidad bajas, mientras que los endoscópicos son generalmente inespecíficos(AU)

Background: the gastrointestinal (GI) tract is the major target site of the graft-versus-host disease (GVHD). Diagnosis is based on endoscopic and histological findings. Material and methods: we performed a retrospective study from January 1st, 1990 to December 31st, 2008 on 338 upper gastrointestinal endoscopies (gastroscopies) performed to 197 patients that underwent an allogeneic transplant with clinical suspicion of GI-GVHD. Results: endoscopic findings to the diagnosis of GVHD have a sensitivity (S) of 34%, specificity levels (SP) of 65%, a positive predictive value (PPV) of 73% and a negative predictive value (NPV) of 48%. The histological study of the endoscopic biopsies has a global sensibility of 85.6% SP = 34.6% PPV = 64.2% and NPV = 63.7%. Histological grade was correlated with the clinical grade of acute GVHD (p = 0.018). Conclusion: upper gastrointestinal endoscopy is useful for the diagnosis of GVHD, as it allows biopsies that can ultimately lead to the diagnosis, but with limited accuracy because the histological findings have low sensitivity and specificity, while the endoscopic findings are generally nonspecific(AU)

Papel de las proteínas quinasas activadas por mitógenos (MAPK) en el carcinoma de células renales esporádico / Role of Mitogen-Activated Protein Kinase (MAPK) in the Sporadic Renal Cell Carcinoma

Contexto: Últimamente, basándose en la implicación del gen supresor vhl en los casos de carcinoma de células renales (CCR), se ha evaluado la implicación de la ruta de señalización entre pVHL y el factor inducible por hipoxia 1 alfa (HIF-1α), ante la necesidad de encontrar nuevos marcadores diagnósticos, pronósticos y de respuesta a fármacos. Síntesis de evidencia: La sobreexpresión de HIF-1α confiere mejor pronóstico en pacientes afectos de CCR de tipo células claras (ccRCC). Además HIF-1α regula otros genes, concretamente el de la anhidrasa carbónica IX (CA-IX), cuya sobreexpresión es prácticamente exclusiva de los ccRCC y su determinación útil para el diagnóstico de este subtipo. Sin embargo, no se ha demostrado la implicación de CA-IX ni en el pronóstico ni en la respuesta a inmunomoduladores o antiangiogénicos. Ello hace necesario la evaluación global de toda esta ruta: pVHL → HIF-1α → CA-IX, e incluso el análisis de otras proteínas y vías de señalización que también controlan la actividad de HIF-1α. En este último caso, las MAPK, son críticas en la activación de HIF-1α, existiendo evidencias a nivel experimental del control sobre su actividad, aunque no se ha establecido su papel clínico como biomarcador. Si bien está demostrado el papel de las MAPK en los fenómenos de resistencia a quimio y radioterapia convencional, no lo está en la respuesta a sorafenib, dato llamativo si tenemos en cuenta que es inhibidor de varias proteín quinasas. Recientemente se ha observado que las MAPK pueden estar implicadas en la respuesta a distintas terapias, incluidas las basadas en inhibidores de tirosín quinasa. Conclusiones: La confirmación de estos datos supondrá una explicación a la variación observada entre pacientes, que con una misma alteración funcional del gen vhl presentan un distinto comportamiento biológico y clínico, y a una mejor selección de terapias no quirúrgicas (AU)

Context: Only on the basis of the involvement of the vhl suppressor gene in the cases of renal cell carcinomas (RCC), the involvement of the signaling pathway between the pVHL and the Hypoxia inducible factor 1, alpha (HIF-1α) has been evaluated because of the need to find new diagnostic and prognostic and response to drugs markers. Evidence synthesis: The overexpression of HIF-1α confers better prognosis in clear cell type RCC (ccRCC). Furthermore, HIF-1α regulates other genes, specifically that of the carbon anhydrase IX (CA-IX), whose overexpression is practically only of the ccRCC and its determination is useful for this subtype. However, the involvement of the CA-IX has not been demonstrated in the prognosis or in the response to immunomodulators or antiangiogenics. Therefore, it is necessary to make a global evaluation of all this pathway: pVHL → HIF-1α → CA-IX, and even the analysis of other proteins and signaling pathways that also control the HIF-1α activity. In the latter case, the MAPK are critical in the HIF-1α activation, there being evidence on the experimental level of the control on its activity. although its clinical role as a biomarkers has not been established. Although the role of the MAPK in the phenomena of resistance to conventional chemotherapy and radiotherapy has been demonstrated, it has not been demonstrated in response to sorafenib, an important piece of information if we consider that it is an inhibitor of several protein kinases. Recently, it has been observed that the MAPK may be involved in the responses to different therapies, included those based on tyrosine kinase inhibitors. Conclusions: The confirmation of these data would suppose an explanation of the variation observed between patients who, with the same functional alteration of the vhl gene, have a different biological, clinical behavior and better selection of non-surgical therapies (AU)

Papel de p38 MAPK en los efectos de la inhibición de la biosíntesis de colesterol en la progresión del ciclo celular en la línea promielocítica humana HL-60 / Role of p38 MAPK in the effects of cholesterol biosynthesis inhibition on cell cycle progression in HL-60 cells

Introducción. El colesterol es necesario para la proliferación y la correcta progresión del ciclo celular. La inhibición sostenida de la biosíntesis de colesterol inhibe la citocinesis y da lugar a la aparición de células poliploides, efectos que pueden implicar la participación de las vías de estrés. Objetivo. Estudiar el efecto de la inhibición terminal de la biosíntesis de colesterol sobre la vía de p38 MAPK y su papel en la progresión del ciclocelular. Metodología. La inhibición de la biosíntesis de colesterol en las células promielocíticas humanasHL-60 se llevó a cabo con SKF 104976. En determinados casos, junto a este inhibidor, se inhibieron las vías de p38 MAPK y ERK1/2empleando SB 203580 y PD 98059,respectivamente. El ciclo celular se estudió por marcaje con yoduro de propidio e incorporación de bromodesoxiuridina y análisis por citometría de flujo, y la expresión de proteínas se analizó por Western blot. Resultados. La inhibición de la biosíntesis de colesterol produjo la acumulación de células enG2/M y una activación transitoria de p38 MAPK, efectos que fueron revertidos por las lipoproteínas de baja densidad (LDL), demostrando que se debían a la deficiencia de colesterol. En aquellas condiciones, la adición de SB 203580 aceleró la replicación del ADN acompañada de un aumento de la poliploidía. Contrariamente, la adición de PD98059 inhibió la síntesis de ADN. Ni la inhibición de p38 MAPK ni la de ERK impidieron la división de las células previamente tratadas con SKF104976 tras suplementarlas con LDL, ni de las células previamente sincronizadas en prometafase con nocodazol. Conclusiones. La inhibición de la biosíntesis de colesterol activa la vía de p38 MAPK a fin de impedir la poliploidía pero no tiene efecto sobre la culminación de la mitosis (AU)

Introduction. Cells require cholesterol for proliferation and correct progression of the cell cycle. In the absence of cholesterol, the cells fail tounder go cytokines is and polynucleated cells are generated. These effects could be mediated by stress signal transduction pathways. Objective. To study the effects of cholesterol biosynthesis inhibition on the activity of p38MAPK and to evaluate the role of this pathway on cell cycle progression. Methodology. Human leukemia cells (HL-60)were incubated in the presence of SKF 104976, an inhibitor of cholesterol biosynthesis. In some cases inhibitors of p38 MAPK and ERK1/2, namely SB203580 and PD 98059, were added to the medium. Cell cycle progression was studied by flow citometry, both DNA content and bromodeoxyuridine incorporation into DNA, and protein expression of p38 MAPK was analyzed by western blot. Results. Inhibition of cholesterol biosynthesis led to accumulation of cells in G2/M and a transient activation of p38 MAPK. These effects were reversed by supplementing the medium with LDL. The addition of SB 203580 accelerated DNA replication, which was accompanied by an increase of polyploidy. By contrast, the addition of PD98059 inhibited DNA synthesis. Lastly, neither the inhibition of p38 MAPK nor ERK affected the division of cells treated with the cholesterol biosynthesis inhibitor following LDL provision, or mitosis completion from metaphase of cells previously synchronized with nocodazole. Conclusions. Cholesterol deficiency induces p38MAPK pathway activation in order to prevent polyploidy, but has no effect on mitosis completion (AU)

Learning from yeasts: intracellular sensing of stress conditions / Aprendiendo de las levaduras: percepción intracelular de las condiciones de estrés

One intriguing challenge in modern biology is to understand how cells respond to, and distinguish between different stressing stimuli. Evidence accumulated in recent years indicates that a network of signaling pathways extends from the plasma membrane to the very core of the cell nucleus to transduce environmental changes into a graded transcriptional response. Although many steps still remain unclear, studies on the stress-activated protein kinase (SAPK) pathways and related mechanisms provide insight into the biochemistry that regulates signal transmission and leads to outcomes such as cell adaptation and differentiation. This review focuses on selected topics of current interest related to the sensing of stress signals in cells of the fission yeast Schizosaccharomyces pombe. Because signaling pathways appear to be evolutionarily well conserved, yeasts may be useful models to learn how higher eukaryotes sense and respond to stresses at the cellular level (AU)

Uno de los desafíos más intrigantes de la biología moderna es comprender cómo responden las células a diferentes estímulos estresantes y cómo los distinguen. Las pruebas acumuladas en los últimos años indican que una red de señales se extiende desde la membrana del citoplasma hasta el núcleo celular para transducir los cambios ambientales en una respuesta transcripcional satisfactoria. Aunque muchos pasos aún no están claros, estudios sobre la vía de la proteína quinasa activada por estrés (SAPK) y mecanismos afines proporcionan una nueva percepción de la bioquímica que regula la señal de transmisión y lleva a resultados tales como la adaptación y diferenciación celular. Esta revisión se centra en aspectos seleccionados de interés actual relativos a la percepción de señales de estrés en células de fisión de la levadura Schizosaccharomyces pombe. Debido a que las vías de señal parecen estar, desde un punto de vista evolutivo, bien conservadas, las levaduras podrían ser modelos útiles para aprender cómo perciben el estrés los eucariotas superiores y como responden al mismo a nivel celular (AU)

Señalización celular en el hipocampo epiléptico / Cell signaling in the epileptic hippocampus

La señalización celular que manda sobre la muerte o la supervivencia en el hipocampo epiléptico humano es difícil de identificar a causa del prolongado intervalo entre el comienzo de los síntomas y el muestreo del tejido cerebral dañado para el examen neuropatológico. La inyección intraperitonial del glutamato análogo del ácido kaínico (AK) es una herramienta útil para el análisis de los efectos de convulsiones y el daño excitotóxico en el hipocampo del roedor. El AK actúa sobre los receptores NMDA y AK, mientras que el impacto sobre los receptores AMPA es muy pequeño. Las neuronas del hilio y las neuronas CA3 son dianas primarias del AK, aunque las neuronas gabérgicas que contienen parvoalbúmina son menos vulnerables que las neuronas glutamatérgicas. Las respuestas inmediatas al AK son la inducción de hsp-70, ARNm y la expresión de la proteína HSP-70/72, junto con c-fos y c-jun ARNm, y la expresión de las proteínas c-Fos y cJun en el hipocampo, aunque la expresión aumentada de c-Fos y c-Jun no predice la muerte celular o la supervivencia de la misma. Por el contrario, el activador del plasminógeno tisular (tPA) y la vía de señal de la membrana Fas/FasL probablemente tenga un papel facilitador en el seguimiento de la muerte celular por la inyección de AK. La afectación de otras vías permanece controvertida. Un aumento en la expresión de Bas pro-apotótico junto con una reducción en Bcl-2 sugiere apoptosis ayudado por Bax. La activación de la vía mitocondrial incluye el escape del citocromo c al citosol y activación de la cascada caspasa que lleva a la apoptosis. Sin embargo, otros estudios han puesto de relieve la expresión limitada de la caspasa-3, el ejecutor principal de la apoptosis, y la relevancia de necrosis como la forma principal de la muerte celular después de la excitotoxicidad del AK. La activación fosforilación dependiente de varias cinasas, entre ellas MAPK, p38 y JNK/SAPK, y sus sustratos, se ha encontrado en los animales tratados con AK. La expresión disminuida de CREBp se asocia con la muerte celular, mientras que el aumento en ATF-2P y Elk-1P se asocia con la supervivencia celular. Los factores tróficos probablemente no desempeñan un papel significativo en las etapas iniciales del daño hipocampal, pero tienen su importancia en el remodelado de las células granulares y el brote de fibras musgosas a la capa molecular del giro dentado. Esta regeneración anómala , a su vez, facilita el `reclutamiento' y mantenimiento crónico de las convulsiones (AU)