Search results for "MAP kinase"
showing 10 items of 178 documents
Effects of cerivastatin on adrenergic pathways, hypertrophic growth and TGFbeta expression in adult ventricular cardiomyocytes.
2010
Abstract The effects of statin treatment in the setting of heart failure have already been shown. Nevertheless, there is little knowledge about its influence on adrenergic pathways in cardiomyocytes. Therefore, this study investigated the impact of cerivastatin on adrenoceptor-mediated signalling pathways in isolated adult ventricular cardiomyocytes. It focused on two endpoints: hypertrophic growth and TGFbeta expression. Cultured cardiomyocytes were used to study rac activation (analysed by its translocation into the membrane fraction), ROS formation (H 2 DCF fluorescence) and hypertrophic growth ( 14 C-phenylalanine incorporation). Alpha- and beta-adrenoceptor stimulation showed significa…
Altered REDD1, myostatin, and Akt/mTOR/FoxO/MAPK signaling in streptozotocin-induced diabetic muscle atrophy
2011
Type 1 diabetes, if poorly controlled, leads to skeletal muscle atrophy, decreasing the quality of life. We aimed to search highly responsive genes in diabetic muscle atrophy in a common diabetes model and to further characterize associated signaling pathways. Mice were killed 1, 3, or 5 wk after streptozotocin or control. Gene expression of calf muscles was analyzed using microarray and protein signaling with Western blotting. We identified translational repressor protein REDD1 (regulated in development and DNA damage responses) that increased seven- to eightfold and was associated with muscle atrophy in diabetes. The diabetes-induced increase in REDD1 was confirmed at the protein level. …
Muscle protein synthesis, mTORC1/MAPK/Hippo signaling, and capillary density are altered by blocking of myostatin and activins
2012
Loss of muscle mass and function occurs in various diseases. Myostatin blocking can attenuate muscle loss, but downstream signaling is not well known. Therefore, to elucidate associated signaling pathways, we used the soluble activin receptor IIb (sActRIIB-Fc) to block myostatin and activins in mice. Within 2 wk, the treatment rapidly increased muscle size as expected but decreased capillary density per area. sActRIIB-Fc increased muscle protein synthesis 1–2 days after the treatment correlating with enhanced mTORC1 signaling (phosphorylated rpS6 and S6K1, r = 0.8). Concurrently, increased REDD1 and eIF2Bε protein contents and phosphorylation of 4E-BP1 and AMPK was observed. In contrast, pr…
Cannabinoid receptor 1 and acute resistance exercise – In vivo and in vitro studies in human skeletal muscle
2015
Abstract Aim This study aimed to determine whether Cannabinoid receptor 1 (CB1) is involved in mammalian target of rapamycin (mTOR) signaling and skeletal muscle protein synthesis. Methods This study used human vastus lateralis skeletal muscle biopsies obtained before and after a resistance exercise (RE) bout in young men (n = 18). The signaling mechanisms were studied in vitro in human myotubes. Protein expression was determined by Western blot and confocal microscopy, and gene expression by quantitative PCR. Protein synthesis was measured in vitro using puromycin-based SuNSET technique. Results In human skeletal muscle, an anabolic stimulus in the form of RE down-regulated CB1 expression.…
Adenosine A2A receptors in diffuse dermal fibrosis: pathogenic role in human dermal fibroblasts and in a murine model of scleroderma.
2006
Objective Adenosine regulates inflammation and tissue repair, and adenosine A2A receptors promote wound healing by stimulating collagen matrix production. We therefore examined whether adenosine A2A receptors contribute to the pathogenesis of dermal fibrosis. Methods Collagen production by primary human dermal fibroblasts was analyzed by real-time polymerase chain reaction, 14C-proline incorporation, and Sircol assay. Intracellular signaling for dermal collagen production was investigated using inhibitors of MEK-1 and by demonstration of ERK phosphorylation. In vivo effects were studied in a bleomycin-induced dermal fibrosis model using adenosine A2A receptor–deficient wild-type littermate …
Overlapping phenotypes between SHORT and Noonan syndromes in patients with PTPN11 pathogenic variants
2020
Overlapping syndromes such as Noonan, Cardio-Facio-Cutaneous, Noonan syndrome (NS) with multiple lentigines and Costello syndromes are genetically heterogeneous conditions sharing a dysregulation of the RAS/mitogen-activated protein kinase (MAPK) pathway and are known collectively as the RASopathies. PTPN11 was the first disease-causing gene identified in NS and remains the more prevalent. We report seven patients from three families presenting heterozygous missense variants in PTPN11 probably responsible for a disease phenotype distinct from the classical Noonan syndrome. The clinical presentation and common features of these seven cases overlap with the SHORT syndrome. The latter is the c…
DNA Methylation in Inflammatory Pathways Modifies the Association between BMI and Adult-Onset Non-Atopic Asthma
2019
A high body mass (BMI) index has repeatedly been associated with non-atopic asthma, but the biological mechanism linking obesity to asthma is still poorly understood. We aimed to test the hypothesis that inflammation and/or innate immunity plays a role in the obesity-asthma link. DNA methylome was measured in blood samples of 61 non-atopic participants with asthma and 146 non-atopic participants without asthma (non-smokers for at least 10 years) taking part in the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA) study. Modification by DNA methylation of the association of BMI or BMI change over 10 years with adult-onset asthma was examined at each CpG sit…
Manganese interferes with calcium, perturbs ERK signaling, and produces embryos with no skeleton.
2011
Manganese (Mn) has been associated with embryo toxicity as it impairs differentiation of neural and skeletogenic cells in vertebrates. Nevertheless, information on the mechanisms operating at the cellular level remains scant. We took advantage of an amenable embryonic model to investigate the effects of Mn in biomineral formation. Sea urchin (Paracentrotus lividus) embryos were exposed to Mn from fertilization, harvested at different developmental stages, and analyzed for their content in calcium (Ca), expression of skeletogenic genes, localization of germ layer markers, and activation of the extracellular signal-regulated kinase (ERK). By optical and immunofluorescence microscopy, we found…
CONSERVED CELLULAR AND MOLECULAR MECHANISMS IN DEVELOPMENT
2002
This review discusses examples of conserved cellular and molecular mechansims in development, including the pathway of signal transduction between the photoreceptors R8 and R7 in Drosophila, which is compared to vulval induction in Caenorhabditis elegans. The Wg pathway in Drosophila is compared, first, to the Wnt pathway in dorsal mesoderm specification in Xenopus: second, to the same pathway in sea urchins; third, to the equivalent in the mom cascade of C. elegans; and finally, to parts of the equivalent pathway in Dictyostelium discoideum. The conserved expression of some hox genes in vertebrate limb buds and in the heads or tails of several invertebrate and vertebrate embryos is also il…
Hypertrophic agonists induce the binding of c-Fos to an AP-1 site in cardiac myocytes: implications for the expression of GLUT1
2003
Objectives: Serum is among the agents known to induce hypertrophy of cardiac myocytes, which occurs concomitant with an increase in AP-1-mediated transcription. We have examined if this effect correlates with changes in the relative abundance of particular AP-1 heterodimers, as their exact composition under these conditions is unknown. Furthermore, we obtained insight on the specific role of c-Fos from studying the induction of the glucose transporter GLUT1 by serum in fibroblasts. Methods: We characterised the AP-1 heterodimers expressed in neonatal cardiac myocytes by supershift electrophoretic mobility shift assay (EMSA) analysis. Quantitative changes in transcription were measured using…