Search results for " MAPK"

AM fungal exudates activate MAP kinases in plant cells in dependence from cytosolic Ca2+ increase

2011

International audience; The molecular dialogue occurring prior to direct contact between the fungal and plant partners of arbuscular-mycorrhizal (AM) symbioses begins with the release of fungal elicitors, so far only partially identified chemically, which can activate specific signaling pathways in the host plant. We show here that the activation of MAPK is also induced by exudates of germinating spores of Gigaspora margarita in cultured cells of the non-leguminous species tobacco (Nicotiana tabacum), as well as in those of the model legume Lotus japonicus. MAPK activity peaked about 15 min after the exposure of the host cells to the fungal exudates (FE). FE were also responsible for a rapi…

Cytosolic calcium rises and related events in ergosterol-treated Nicotiana cells

2011

International audience; The typical fungal membrane component ergosterol was previously shown to trigger defence responses and protect plants against pathogens. Most of the elicitors mobilize the second messenger calcium, to trigger plant defences. We checked the involvement of calcium in response to ergosterol using Nicotiana plumbaginifolia and Nicotiana tabacum cv Xanthi cells expressing apoaequorin in the cytosol. First, it was verified if ergosterol was efficient in these cells inducing modifications of proton fluxes and increased expression of defence-related genes. Then, it was shown that ergosterol induced a rapid and transient biphasic increase of free [Ca2þ]cyt which intensity dep…

PTEN status is a crucial determinant of the functional outcome of combined MEK and mTOR inhibition in cancer

2017

AbstractCombined MAPK/PI3K pathway inhibition represents an attractive, albeit toxic, therapeutic strategy in oncology. Since PTEN lies at the intersection of these two pathways, we investigated whether PTEN status determines the functional response to combined pathway inhibition. PTEN (gene, mRNA, and protein) status was extensively characterized in a panel of cancer cell lines and combined MEK/mTOR inhibition displayed highly synergistic pharmacologic interactions almost exclusively in PTEN-loss models. Genetic manipulation of PTEN status confirmed a mechanistic role for PTEN in determining the functional outcome of combined pathway blockade. Proteomic analysis showed greater phosphoprote…

Dual targeting of HER3 and MEK may overcome HER3-dependent drug-resistance of colon cancers

2016

// Giulia Bon 1, * , Rossella Loria 1, * , Carla Azzurra Amoreo 2 , Alessandra Verdina 1 , Isabella Sperduti 2 , Arianna Mastrofrancesco 3 , Silvia Soddu 1 , Maria Grazia Diodoro 2 , Marcella Mottolese 2 , Matilde Todaro 4 , Giorgio Stassi 4 , Michele Milella 5 , Ruggero De Maria 6 , Rita Falcioni 1 1 Department of Research, Advanced Diagnostic, and Technological Innovation, IRCCS Regina Elena National Cancer Institute, Rome, Italy 2 Department of Research, Advanced Diagnostic, and Technological Innovation, IRCCS Regina Elena National Cancer Institute, Rome, Italy 3 Physiopathology Laboratory of Skin, IRCCS San Gallicano Dermatological Institute, Rome, Italy 4 Surgical and Oncological Scien…

TRIBUTYLTIN-INDUCED EFFECTS ON MAPK SIGNALING IN ASCIDIAN EMBRYOS

2008

Among the class of organotin compounds, the most well known is tributyltin (TBT). Organotin have many applications, which include use in PVC, as catalyst in chemical reactions, agricultural pesticides and antifungal treatments for textile polymers. In particular TBT is used in marine antifoulant paints to prevent the growth of organisms such as barnacles on the hull of ships. Extensive use in antifouling paints led to the widespread distribution of TBT and its breakdown products in the global marine, sediment and biota. High levels of TBT in the waters were found to have impaired reproduction, by inhibiting embryogenesis and larval development in a variety of marine organisms. Symptoms of t…

Role of Adrenomedullin in LSP-mediated lung injury

2014

Lipocalin-2 Regulates Hippocampal Microglial Activation in Poststroke Depression

2021

Background and Purpose: Microglia play important role in poststroke depression (PSD), however, the exact mechanism was still unclear. The purpose of the study was to study the mechanism of microglial activation in PSD.Methods: 24 rats were randomly divided into three groups: the PSD group (n = 10), the poststroke (PS) group (n = 7), and the sham group (n = 7). Primary hippocampal microglia were isolated and cultured, and recombined LCN2 protein was used to stimulate the cultured microglia. The protein expression of Iba1, P38 MAPK and PP38 MAPK was analyzed by western blotting; the LCN2 expression was measured by RT-qPCR, the serum LCN2 level and the NO level were analyzed by ELISA.Results: …

Agonist-induced formation of FGFR1 homodimers and signaling differ among members of the FGF family

2011

Fibroblast growth factor receptor 1 (FGFR1) is known to be activated by homodimerization in the presence of both the FGF agonist ligand and heparan sulfate glycosaminoglycan. FGFR1 homodimers in turn trigger a variety of downstream signaling cascades via autophosphorylation of tyrosine residues in the cytoplasmic domain of FGFR1. By means of Bioluminescence Energy Resonance Transfer (BRET) as a sign of FGFR1 homodimerization, we evaluated in HEK293T cells the effects of all known FGF agonist ligands on homodimer formation. A significant correlation between BRET(2) signaling and ERK1/2 phosphorylation was observed, leading to a further characterization of the binding and signaling properties…

Regulation of the effects of CYP2E1-induced oxidative stress by JNK signaling

2014

The generation of excessive amounts of reactive oxygen species (ROS) leads to cellular oxidative stress that underlies a variety of forms of hepatocyte injury and death including that from alcohol. Although ROS can induce cell damage through direct effects on cellular macromolecules, the injurious effects of ROS are mediated largely through changes in signal transduction pathways such as the mitogen-activated protein kinase c-Jun N-terminal kinase (JNK). In response to alcohol, hepatocytes have increased levels of the enzyme cytochrome P450 2E1 (CYP2E1) which generates an oxidant stress that promotes the development of alcoholic steatosis and liver injury. These effects are mediated in larg…

Synthesis of polyfluoroalkyl sp2-iminosugar glycolipids and evaluation of their immunomodulatory properties towards anti-tumor, anti-leishmanial and …

2019

Immunomodulatory glycolipids, among which α-galactosylceramide (KRN7000) is an iconic example, have shown strong therapeutic potential in a variety of conditions ranging from cancer and infection to autoimmune or neurodegenerative diseases. A main difficulty for those channels is that they often provoke a cytokine storm comprising both pro- and anti-inflammatory mediators that antagonize each other and negatively affect the immune response. The synthesis of analogues with narrower cytokine secretion-inducing capabilities is hampered by the intrinsic difficulty at controlling the stereochemical outcome in glycosidation reactions, particularly if targeting the α-anomer, which seriously hamper…