Roodveldt, CintiaLabrador-Garrido, AdahirGonzalez-Rey, ElenaLachaud, Christian CGuilliams, TimFernandez-Montesinos, RafaelBenitez-Rondan, AliciaRobledo, GemaHmadcha, AbdelkrimDelgado, MarioDobson, Christopher MPozo, David2016-07-142016-07-142013Roodveldt C, Labrador-Garrido A, Gonzalez-Rey E, Lachaud CC, Guilliams T, Fernandez-Montesinos R, et al. Preconditioning of microglia by α-synuclein strongly affects the response induced by toll-like receptor (TLR) stimulation. PLoS ONE; 8(11):e79160http://hdl.handle.net/10668/2279Journal Article; Research Support, Non-U.S. Gov't;In recent years, it has become accepted that α-synuclein (αSyn) has a key role in the microglia-mediated neuroinflammation, which accompanies the development of Parkinson's disease and other related disorders, such as Dementia with Lewy Bodies and Alzheimer's disease. Nevertheless, the cellular and molecular mechanisms underlying its pathological actions, especially in the sporadic forms of the diseases, are not completely understood. Intriguingly, several epidemiological and animal model studies have revealed a link between certain microbial infections and the onset or progression of sporadic forms of these neurodegenerative disorders. In this work, we have characterized the effect of toll-like receptor (TLR) stimulation on primary murine microglial cultures and analysed the impact of priming cells with extracellular wild-type (Wt) αSyn on the subsequent TLR stimulation of cells with a set of TLR ligands. By assaying key interleukins and chemokines we report that specific stimuli, in particular Pam3Csk4 (Pam3) and single-stranded RNA40 (ssRNA), can differentially affect the TLR2/1- and TLR7-mediated responses of microglia when pre-conditioned with αSyn by augmenting IL-6, MCP-1/CCL2 or IP-10/CXCL10 secretion levels. Furthermore, we report a skewing of αSyn-primed microglia stimulated with ssRNA (TLR7) or Pam3 (TLR2/1) towards intermediate but at the same time differential, M1/M2 phenotypes. Finally, we show that the levels and intracellular location of activated caspase-3 protein change significantly in αSyn-primed microglia after stimulation with these particular TLR agonists. Overall, we report a remarkable impact of non-aggregated αSyn pre-sensitization of microglia on TLR-mediated immunity, a phenomenon that could contribute to triggering the onset of sporadic α-synuclein-related neuropathologies.enMicroglial cellsCytokinesToll-Like ReceptorsFluorescence microscopyPhagocytosisChemokinesFluorescence imagingSecretionReceptores Toll-LikeCitocinasMicroscopía FluorescenteFagocitosisMedical Subject Headings::Organisms::Eukaryota::AnimalsMedical Subject Headings::Chemicals and Drugs::Enzymes and Coenzymes::Enzymes::Hydrolases::Ureohydrolases::ArginaseMedical Subject Headings::Organisms::Bacteria::Gram-Positive Bacteria::Bacillales::Bacillaceae::Bacillus::Bacillus subtilisMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Peptides::Intracellular Signaling Peptides and Proteins::Apoptosis Regulatory Proteins::Caspases::Caspases, Effector::Caspase 3Medical Subject Headings::Phenomena and Processes::Cell Physiological Phenomena::Cell PolarityMedical Subject Headings::Anatomy::Cells::Cells, CulturedMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Peptides::Intercellular Signaling Peptides and Proteins::CytokinesMedical Subject Headings::Phenomena and Processes::Genetic Phenomena::Genetic Processes::Gene ExpressionMedical Subject Headings::Phenomena and Processes::Immune System Phenomena::Immunity::Immunity, InnateMedical Subject Headings::Check Tags::MaleMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Rodentia::Muridae::Murinae::MiceMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Rodentia::Muridae::Murinae::Mice::Mice, Inbred Strains::Mice, Inbred C57BLMedical Subject Headings::Anatomy::Cells::Neuroglia::MicrogliaMedical Subject Headings::Chemicals and Drugs::Enzymes and Coenzymes::Enzymes::Oxidoreductases::Oxidoreductases Acting on CH-NH2 Group Donors::Amino Acid Oxidoreductases::Nitric Oxide Synthase::Nitric Oxide Synthase Type IIMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Peptides::Glycopeptides::PeptidoglycanMedical Subject Headings::Chemicals and Drugs::Nucleic Acids, Nucleotides, and Nucleosides::Nucleotides::Polynucleotides::Polyribonucleotides::Poly C::Poly I-CMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Membrane Proteins::Receptors, Cell Surface::Receptors, Immunologic::Receptors, Pattern Recognition::Toll-Like ReceptorsMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Nerve Tissue Proteins::Synucleins::alpha-SynucleinMedical Subject Headings::Chemicals and Drugs::Heterocyclic Compounds::Heterocyclic Compounds, 2-Ring::Quinolines::Aminoquinolinesresearch article24236103open access10.1371/journal.pone.00791601932-6203PMC3827304