Monocyte chemotactic protein-1 gene expression and translation in formed granulomatous calcified tissue in vivo

Monocyte chemotactic protein-1 (MCP-1) and related molecules constitute the C-C class of the β chemokine supergene family with inflammatory properties. However, the exact role, function, and implication in inflammatory diseases remain to be determined. Here we report that subcutaneous injections (0.2 ml) of a saturated water solution (1:40) of potassium permanganate crystals induces the generation of granuloma tissue at the site of injection in the rat, and reaches its peak of formation after 1 week. The size and weight of the granulomas were increased by i.p. lipopolysaccharide (LPS) (6 μg/200 μl) and inhibited by intraperitoneal (i.p.) dexamethasone (Dxs) 300 μg/200 μl) treatments in rats, injected 18 hours before sacrifice. Moreover, steady-state levels of MCP-1 mRNA in the granuloma tissue (control), were strongly generated. Rats treated i.p. with LPS produced an increase of MCP-1 mRNA in the granuloma tissue compared with controls (i.p. PBS-treated) whereas in animals treated with Dxs, there was a decrease in (P < 0.05) in formation of mRNA protein. When the granuloma tissues were homogenized the generation of MCP-1 was found in the supernatants. The level of MCP-1 was higher (P < 0.05) in the LPS-treated animals and lower (P < 0.05) in the Dxs group compared with the controls (treated with PBS). Similar results were obtained in the serum and in minced granuloma tissue where samples were further incubated in vitro with LPS (100 ng/ml) overnight. A Strong increase (P < 0.01) in MCP-1 in all samples was detected, but not in the minced granuloma tissue from Dxs-treated animals. Our data demonstrate that calcified tissue from chronic inflammation induced by KMnO4 generates MCP-1 gene expression and translation, an effect increased by LPS and decreased by Dxs

Augmentation of monocyte chemotactic protein-1 and mRNA transcript in chronic inflammatory states induced by potassium permanganate (kMnO4) in vivo

Monocyte chemotactic protein-1 (MCP-1) is a proinflammatory cytokine that attracts and activates specific types of leucocytes. The purpose of this work was to analyse the generation of MCP-1 and mRNA transcript in a model of chronic inflammation using a granulomatous tissue induced by potassium permanganate (KMnO4; water soluble crystals). The data presented here shows that MCP-1 is generated in granuloma tissue and its level was strongly increased by i.p. injections of lipopolysaccharide (LPS) and inhibited in rats treated with injections of dexamethasone, 18 hr before the animals were killed. In histological studies LPS and dexamethasone increased and decreased, respectively, the recruitment of mononuclear cells in the granuloma tissue compared with the control granulomas from phosphate-buffered saline (PBS)-treated animals. Reverse transcriptase- polymerase chain reaction (RT-PCR) was used for mRNA extraction and cDNA synthesis. mRNA MCP-1 was significantly produced in the granuloma tissue of untreated animals, an effect increased by LPS and inhibited by dexamethasone, compared with the controls. Moreover, MCP-1 protein was found in the supernatant from homogenized granuloma tissues and the levels of MCP-1 were higher in the LPS-treated animals, while they were lower in the dexamethasone group, compared with the granulomas from the PBS-treated groups (control). The generation of MCP-1 was also found in minced granuloma tissue incubated for 18 hr (overnight) from treated (LPS or dexamethasone) and untreated (PBS) rats. When LPS was added in vitro for 18 hr to the controls and treated animals the production of MCP-1 was further increased except in the dexamethasone group (P>0.05). Analysing blood serum from LPS, dexamethasone or PBS-treated rats, we found that MCP-1 was also present. The level was higher in the LPS group and lower in the dexamethasone group, compared with the control (PBS). In these studies we show for the first time that MCP-1 transcript and translation is generated in chronic experimental inflammatory tissue, an effect inhibited by dexamethasone

Augmentation of monocyte chemotactic protein-1 and mRNA transcript in chronic inflammatory states induced by potassium permanganate (kMnO4) in vivo

Monocyte chemotactic protein-1 (MCP-1) is a proinflammatory cytokine that attracts and activates specific types of leucocytes. The purpose of this work was to analyse the generation of MCP-1 and mRNA transcript in a model of chronic inflammation using a granulomatous tissue induced by potassium permanganate (KMnO4; water soluble crystals). The data presented here shows that MCP-1 is generated in granuloma tissue and its level was strongly increased by i.p. injections of lipopolysaccharide (LPS) and inhibited in rats treated with injections of dexamethasone, 18 hr before the animals were killed. In histological studies LPS and dexamethasone increased and decreased, respectively, the recruitment of mononuclear cells in the granuloma tissue compared with the control granulomas from phosphate-buffered saline (PBS)-treated animals. Reverse transcriptase- polymerase chain reaction (RT-PCR) was used for mRNA extraction and cDNA synthesis. mRNA MCP-1 was significantly produced in the granuloma tissue of untreated animals, an effect increased by LPS and inhibited by dexamethasone, compared with the controls. Moreover, MCP-1 protein was found in the supernatant from homogenized granuloma tissues and the levels of MCP-1 were higher in the LPS-treated animals, while they were lower in the dexamethasone group, compared with the granulomas from the PBS-treated groups (control). The generation of MCP-1 was also found in minced granuloma tissue incubated for 18 hr (overnight) from treated (LPS or dexamethasone) and untreated (PBS) rats. When LPS was added in vitro for 18 hr to the controls and treated animals the production of MCP-1 was further increased except in the dexamethasone group (P>0.05). Analysing blood serum from LPS, dexamethasone or PBS-treated rats, we found that MCP-1 was also present. The level was higher in the LPS group and lower in the dexamethasone group, compared with the control (PBS). In these studies we show for the first time that MCP-1 transcript and translation is generated in chronic experimental inflammatory tissue, an effect inhibited by dexamethasone

Massive infiltration of basophilic cells in inflamed tissue after injection of RANTES

Regulated upon activation normal T expressed and secreted (RANTES) is a new inducible protein member of the human C-C branch of chemokines. RANTES is a potent monocyte and lymphocyte chemoattractant and is a mediator of inflammatory responses. In these studies we found that RANTES 10 ng/50 μl chemoattracts basophilic cells in a dose-dependent manner 4 h after an intradermal injection in rat skin sites, as revealed by optic microscopy. Moreover, in biopsy specimens from rat skin injection sites histamine release was significantly higher (P < 0.05) than in controls (PBS 50 μl) after 4 h from RANTES treatment. The presence of basophilic cells in rat skin injection sites after RANTES-treatment was also confirmed by electron microscopy studies. In addition, histidine decarboxylase (HDC) mRNA was increased in rat skin sites injected with RANTES compared to sites injected with PBS (controls). Our report describes additional biological activities for RANTES, suggesting that this human chemoattractant protein may play a fundamental role in histamine and HDC generation, along with basophilic cell recruitment