0000000000414641

AUTHOR

Luca Parente

Sequential release of TNFα and phospholipase A2 in a rat model of LPS-induced pleurisy

The levels of extracellular phospholipase A2(sPLA2) and TNFα, and cell accumulation were measured in the pleural washings obtained at different times following the induction ofEscherichia colilipopolysaccharide (LPS, 100 μg/cavity) pleurisy in rats. TNFα peaked at 2 hours (3036 ± 160.3 units/ml) and decreased thereafter. Conversely, levels of sPLA2peaked at 48 hours (1.97 ± 0.64 ng/ml) and were increased further (14.02 ± 4.16 ng/ml) by pretreatment with anti-TNFα antibody. Cell accumulation was not affected by antibody pretreatment. These data indicate that the sPLA2enzyme is involved in LPS-induced pleurisy. The enzyme seems not to be stimulated by TNFα which may be involved in the downreg…

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Evidence for the neuronal origin of immunoreactive interleukin-1 beta released by rat hypothalamic explants.

In this study, we have investigated the release of immunoreactive interleukin-1 beta (irIL-1 beta) from the rat hypothalamus in vitro. It was found that (1) tissue explants release sizable amounts of irIL-1 beta (ranging from 0.43 to 0.52 pg/mg of wet tissue) in 20 min incubations; (2) basal release in significantly increased by depolarization induced with 56 mM KCl; (3) K(+)-induced irIL-1 beta release is inhibited by the specific blocker of N-type calcium channels, omega-conotoxin, and by verapamil, but not by nifedipine; (4) K(+)-induced release is also inhibited by the Na+ channel blockers tetrodotoxin and lidocaine; (5) irIL-1 beta release is significantly increased by noradrenalin; su…

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Down-regulation of microglial cyclo-oxygenase-2 and inducible nitric oxide synthase expression by lipocortin 1

Activated microglial cells are believed to play an active role in most brain pathologies, during which they can contribute to host defence and repair but also to the establishment of tissue damage. These actions are largely mediated by microglial secretory products, among which are prostaglandins (PGs) and nitric oxide (NO). The anti-inflammatory protein, lipocortin 1 (LC1) was reported to have neuroprotective action and to be induced by glucocorticoids in several brain structures, with a preferential expression in microglia. In this paper we tested whether the neuroprotective effect of LC1 could be explained by an inhibitory effect on microglial activation. We have previously shown that ba…

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Annexin-1 downregulation in thyroid cancer correlates to the degree of tumour differentiation

We investigated the expression of annexin-1 (ANXA1) in thyroid carcinoma cell lines and in thyroid cancers with a different degree of differentiation. The highest level of ANXA1 expression examined by Western blotting was detected in the papillary carcinoma cells (NPA) and in the follicular cells (WRO). On the other hand, the most undifferentiated thyroid carcinoma cells (ARO and FRO) presented the lowest level of ANXA1 expression. In surgical tissue specimens from 32 patients with thyroid cancers, we found high immunoreactivity for ANXA1 in papillary (PTC) and follicular (FTC) thyroid cancers while in undifferentiated thyroid cancers (UTC) the expression of the protein was barely detectabl…

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IL-6 stimulates annexin 1 expression and translocation and suggests a new biological role as class II acute phase protein.

Annexin 1 (Ax 1), a protein whose synthesis and secretion are induced during the inflammatory response, has been proposed as a mediator of the anti-inflammatory action of glucocorticoids. To gain insight into a broader role of Ax 1 during the inflammatory response, the authors have investigated how pro-inflammatory cytokines [interleukin 1 (IL-1), IL-6 and tumour necrosis factor alpha (TNF-alpha)] affect Ax 1 expression and regulation at transcriptional and translational levels. The authors show that induction of the Ax 1 protein and its translocation to the cell membrane are stimulated by interleukin 6. However neither IL-1 nor TNF-alpha display these effects. Analysis of 5'-deletion mutan…

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Induction of annexin-1 during TRAIL-induced apoptosis in thyroid carcinoma cells

We investigated the expression of annexin-1 (ANXA1) in thyroid carcinoma cell lines and in thyroid cancers with a different degree of differentiation. The highest level of ANXA1 expression examined by Western blotting was detected in the papillary carcinoma cells (NPA) and in the follicular cells (WRO). On the other hand, the most undifferentiated thyroid carcinoma cells (ARO and FRO) presented the lowest level of ANXA1 expression. In surgical tissue specimens from 32 patients with thyroid cancers, we found high immunoreactivity for ANXA1 in papillary (PTC) and follicular (FTC) thyroid cancers while in undifferentiated thyroid cancers (UTC) the expression of the protein was barely detectabl…

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Interleukin-1 inhibits drinking behaviour through prostaglandins, but not by nitric oxide formation

Interleukin-1 beta (IL-1 beta) causes inhibition of drinking behaviour. Moreover it induces formation of prostaglandins (PGs) and nitric oxide (NO). Both PGs and NO are able to inhibit drinking stimulated by water deprivation or by intracerebroventricular (i.c.v.) administration of angiotensin II. In this study, we studied in the preoptic area (POA) the possible role of PGs and NO in the antidipsogenic action induced by IL-1 beta. IL-1 beta was injected in the lateral cerebral ventricle (i.c.v.) (2.5, 10, 20, and 40 ng/rat) or into POA (0.625, 1.25, 2.5, and 10 ng/rat). L-arginine (12.5, 25, 50, and 100 ng/rat), the precursor of NO, or NG-nitro-L-arginine methyl ester (L-NAME) (25, 50, and …

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Anti-inflammatory effects of annexin-1: stimulation of IL-10 release and inhibition of nitric oxide synthesis.

Annexin-1 (ANX-1) is an anti-inflammatory protein induced by glucocorticoids. Like glucocorticoids, ANX-1 and derived peptides inhibit eicosanoid synthesis, block leukocyte migration and induce apoptosis of inflammatory cells. Cytokines may possess either pro-inflammatory, i.e. interleukin(IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-12 or anti-inflammatory properties, i.e. IL-4, IL-10. The experiments described in the present study have been performed to answer the question whether the anti-inflammatory action of ANX-1 may be mediated, at least in part, by the release of IL-10. In macrophage (J774) cell line cultures primed with lipolysaccharide (LPS), recombinant ANX-1 stimulated IL-1…

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