Publications by authors named "Viviane Tridon"

Podosomes are specialized plasma-membrane actin-based microdomains that combine adhesive and proteolytic activities to spatially restrict sites of matrix degradation in in vitro assays, but the physiological relevance of these observations remain unknown. Inducible rings of podosomes (podosome rosettes) form in cultured aortic cells exposed to the inflammatory cytokine TGFbeta. In an attempt to prove the existence of podosomes in living tissues, we developed an ex vivo endothelium observation model.

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Interleukin-1beta (IL-1beta) induces cyclooxygenase-2 (Cox-2) expression in many of its cellular targets resulting in production and release of prostaglandins. Although IL-1beta-induced Cox-2 expression most likely requires activation of nuclear transcription factor kappa B (NFkappaB) pathway, this has never been formally demonstrated in vivo. We tested this using a specific inhibitor of NFkappaB activation, the NEMO binding domain (NBD) peptide, that has been shown previously to be effective in various in vivo models of acute inflammation.

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Interleukin-1beta (IL-1beta) plays a major role in the initiation and exacerbation of brain inflammation, and its action is limited by the natural antagonist of IL-1 receptors, IL-1Ra. The aim of the present study was to test the hypothesis that IL-1beta mediates the functional consequences of inflammation during the course of delayed-type hypersensitivity response to bacillus Calmette-Guérin (BCG) in the hippocampus of Lewis rats. Animals were primed with an injection of BCG in the right hippocampus and challenged 4 weeks later with BCG administered subcutaneously.

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Interleukin-1beta (IL-1beta) is a key player in the pathogenesis of acute and chronic inflammatory diseases at the periphery and in the brain. Its action is regulated by interleukin-1 receptor antagonist (IL-1Ra), the specific endogenous antagonist of IL-1 receptors. The ratio between local concentrations of IL-1Ra and IL-1beta is known to influence the initiation and progression of many inflammatory and autoimmune diseases at the periphery.

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The signalling pathways that mediate early central effects of interleukin-1 (IL-1) during the acute phase reaction have been poorly elucidated. Interaction of IL-1beta to its specific receptor interleukin-1 receptor type I (IL-1RI) leads to nuclear factor kappa B (NuFkappaB) nuclear translocation and a robust transcriptional activation of inhibitor of kappa B alpha (IkappaBalpha) within the rat brain. Indeed, we demonstrated that IL-1RI expressed in blood brain barrier (BBB) cells and in circumventricular organs (CVOs) is crucial for p65-NFkappaB translocation induced by peripheral injection of IL-1beta.

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