Anti-inflammatory effect of parenteral fish oil lipid emulsion on human activated mononuclear leukocytes

Background & aim: To compare the effect of fish oil-based (FO) lipid emulsions (LE) for parenteral administration with standard LE and a new FO containing LE composed of four different oils on the antigen presentation and inflammatory variables. Methods: Phytohemagglutinin (PHA) activated human mononuclear leukocytes were cultured with different LE - Control: without LE; SO: soybean oil; SO/FO: soybean and FO (4:1); MCT/SO: medium chain triglycerides and SO (1:1); MCT/SO/FO: MCT/SO and FO (4:1) and SMOF: a new LE containing FO. Cytokine production was evaluated by ELISA, the expression of antigen-presenting and co-stimulatory surface molecules were analyzed by flow cytometry and lymphocyte proliferation was assessed by H(3)-Thymidine incorporation, after tetanus toxoid-induced activation. Results: All LE decreased the HLA-DR and increased CD28 and CD152 expression on monocytes/macrophages and lymphocytes surface (p < 0.05). SO/FO and MCT/SO/FO decreased lymphocyte proliferation (p<0.05). All LE decreased IL-2 product ion, but this effect was enhanced with MCT/SO/FO and SMOF (p < 0.05). MCT/SOTO decreased IL-6 and increased IL-10, whereas SO had the opposite effect (p < 0.05). Conclusion: FO LE inhibited lymphocyte proliferation and had an anti-inflammatory effect. These effects seem to be enhanced when FO is mixed with MCT/SO. SMOF had a neutral impact on lymphocyte proliferation and IL-6 and IL-10 production.

A new model of outbred genetically selected mice which present a strong acute inflammatory response in the absence of complement component C5

Mice selected for a strong (AIRmax) or weak (AIRmin) acute inflammatory response present different susceptibilities to bacterial infections, autoimmune diseases and carcinogenesis. Variations in these phenotypes have been also detected in AIRmax and AIRmin mice rendered homozygous for Slc11a1 resistant (R) and susceptible (S) alleles. Our aim was to investigate if the phenotypic differences observed in these mice was related to the complement system. AIRmax and AIRmin mice and AIRmax and AIRmin groups homozygous for the resistance (R) or susceptibility (S) alleles of the solute carrier family 11a1 member (Slc11a1) gene, formerly designated Nramp-1. While no difference in complement activity was detected in sera from AIRmax and AIRmin strains, all sera from AIRmax Slc11a1 resistant mice (AIRmax(RR)) presented no complement-dependent hemolytic activity. Furthermore, C5 was not found in their sera by immunodiffusion and, polymerase chain reaction and DNA sequencing of its gene demonstrated that AIRmax(RR) mice are homozygous for the C5 deficient (D) mutation previously described in A/J. Therefore, the C5D allele was fixed in homozygosis in AIRmax(RR) line. The AIRmax(RR) line is a new experimental mouse model in which a strong inflammatory response can be triggered in vivo in the absence of C5.

Endogenous Hepatocyte Growth Factor Attenuates Inflammatory Response in Glycerol-Induced Acute Kidney Injury

Background: Hepatocyte growth factor (HGF) is overexpressed after acute kidney injury (AKI). The aim of this study was to evaluate the role of endogenous HGF in the progression of the inflammatory response in glycerol-induced AKI (Gly-AKI) in rats. Methods: Renal and systemic HGF expressions were evaluated during the development of Gly-AKI. Subsequently, the blockade of endogenous HGF was analyzed in rats treated with anti-HGF antibody concomitant to glycerol injection. Apoptosis, cell infiltration and chemokine and cytokine profiles were investigated. Results: We detected an early peak of renal and plasma HGF protein expressions 3 h after glycerol injection. The pharmacological blockade of the endogenous HGF exacerbated the renal impairment, the tubular apoptosis, the renal expression of monocyte chemoattractant protein-1 and the macrophage, CD43+, CD4+ and CD8+ T lymphocytes renal infiltration. The analysis of mRNA expressions of Th1 (t-bet, TNF-alpha, IL-1 beta) and Th2 (gata-3, IL-4, IL-10) cytokines showed a Th1-polarized response in Gly-AKI rats that was aggravated with the anti-HGF treatment. Conclusion: Endogenous HGF attenuates the renal inflammatory response, leukocyte infiltration and Th1 polarization after glycerol injection. The control of cellular immune response may partly explain the protective effect of endogenous HGF in the development of Gly-AKI. Copyright (C) 2008 S. Karger AG, Basel

Human monocytes but not dendritic cells are killed by blocking of autocrine cyclooxygenase activity

Dendritic cells (DCs), in peripheral tissues, derive mostly from blood precursors that differentiate into DCs under the influence of the local microenvironment. Monocytes constitute the main known DC precursors in blood and their infiltration into tissues is up-regulated during inflammation. During this process, the local production of mediators, like prostaglandins (PGs), influence significantly DC differentiation and function. In the present paper we show that treatment of blood adherent mononuclear cells with 10 mu M indomethacin, a dose achieved in human therapeutic settings, causes monocytes` progressive death but does not affect DCs viability or cell surface phenotype. This resistance of DCs was observed both for cells differentiated in vitro from blood monocytes and for a population with DCs characteristics already present in blood. This phenomenon could affect the local balance of antigen-presenting cells, influence the induction and pattern of immune responses developed under the treatment with non-steroidal anti-inflammatory drugs and, therefore, deserves further investigation. (C) 2009 Elsevier Inc. All rights reserved.

Trypanosoma cruzi: parasite shed vesicles increase heart parasitism and generate an intense inflammatory response

Trypanosoma cruzi trypomastigotes continuously shed into the medium plasma membrane fragments sealed as vesicles enriched in glycoproteins of the gp85 and trans-sialidase (TS) superfamily and alpha-galactosyl-containing glycoconjugates. Injection of a vesicle fraction into BALB/c mice prior to T. cruzi infection led to 40% of deaths on the 16th day post-infection and 100% on day 20th whereas 20% of untreated animals survived for more than 30 clays. The vesicle-treated animals developed severe heart pathology, with intense inflammatory reaction and higher number of amastigote nests. Analysis of the inflammatory infiltrates 15 days after infection showed predominance of TCD4(+) lymphocytes and macrophages, but not of TCD8(+) cells, as well as a decrease of areas labeled with anti-iNOS antibodies as compared to the control. Higher levels of IL-4 and IL-10 mRNAs were found in the hearts and higher IL-10 and lower NO levels in splenocytes of vesicles pretreated animals. Treatment of mice with neutralizing anti-IL-10 or anti-IL-4 antibodies precluded the effects of pre-inoculation of membrane vesicles on infection. These results indicate that T. cruzi shed membrane components increase tissue parasitism and inflammation by stimulation of IL-4 and IL-10 synthesis and thus may play a central role in the pathogenesis of Chagas` disease acute phase. (c) 2008 Elsevier Masson SAS. All rights reserved.

Functional interferences in host inflammatory immune response by airway allergic inflammation restrain experimental periodontitis development in mice

Aims Periodontal disease (PD) and airway allergic inflammation (AL) present opposing inflammatory immunological features and clinically present an inverse correlation. However, the putative mechanisms underlying such opposite association are unknown. Material and Methods Balb/C mice were submitted to the co-induction of experimental PD (induced by Actinobacillus actinomycetemcomitans oral inoculation) and AL [induced by sensitization with ovalbumin (OVA) and the subsequent OVA challenges], and evaluated regarding PD and AL severity, immune response [cytokine production at periodontal tissues, and T-helper transcription factors in submandibular lymph nodes (LNs)] and infection parameters. Results PD/AL co-induction decreased PD alveolar bone loss and periodontal inflammation while experimental AL parameters were unaltered. An active functional interference was verified, because independent OVA sensitization and challenge not modulate PD outcome. PD+AL group presented decreased tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, -gamma, IL-17A, receptor activator of nuclear factor kappa-light-chain-enhancer of activated B cells ligand and matrix metalloproteinase (MMP)-13 levels in periodontal tissues, while IL-4 and IL-10 levels were unaltered by AL co-induction. AL co-induction also resulted in upregulated T-bet and related orphan receptor gamma and downregulated GATA3 levels expression in submandibular LNs when compared with PD group. Conclusion Our results demonstrate that the interaction between experimental periodontitis and allergy involves functional immunological interferences, which restrains experimental periodontitis development by means of a skewed immune response.

CCR2 Deficiency Results in Increased Osteolysis in Experimental Periapical Lesions in Mice

Introduction: Periapical lesions are chronic inflammatory disorders of periradicular tissues caused by etiologic agents of endodontic origin. The inflammatory chemokines are thought to be involved in the latter observed osteolysis. With a murine model of experimental periapical lesion, the objective of this study was to evaluate the role of the chemokine receptor CCR2 in the lesion progression, osteoclast differentiation and activation, and expression of inflammatory osteolysis-related mediators. Methods: For lesion induction, right mandibular first molars were opened surgically with a (1)/(4) carbine bur, and 4 bacterial strains were inoculated in the exposed dental pulp; left mandibular first molars were used as controls. Animals were killed at 3, 7, 14, and 21 days after surgeries to evaluate the kinetics of lesion development. Results: CCR2 KO mice showed wider lesions than WT mice. CCR2 KO mice also expressed higher levels of the osteoclastogenic and osteolytic factors, receptor activator of nuclear factor kappa B ligand (RANKL) and cathepsin K, of the proinflammatory cytokine tumor necrosis factor alpha, and of the neutrophil migration related chemokine, KC. Conclusions: These results suggest that CCR2 is important in host protection to periapical osteolysis. (J Endod 2010;36:244-250)

Distinctive Immunomodulatory and Inflammatory Properties of the Escherichia coli Type II Heat-Labile Enterotoxin LT-IIa and Its B Pentamer following Intradermal Administration

The type I and type II heat-labile enterotoxins (LT-I and LT-II) are strong mucosal adjuvants when they are coadministered with soluble antigens. Nonetheless, data on the parenteral adjuvant activities of LT-II are still limited. Particularly, no previous study has evaluated the adjuvant effects and induced inflammatory reactions of LT-II holotoxins or their B pentameric subunits after delivery via the intradermal (i.d.) route to mice. In the present report, the adjuvant and local skin inflammatory effects of LT-IIa and its B subunit pentamer (LT-IIaB(5)) were determined. When coadministered with ovalbumin (OVA), LT-IIa and, to a lesser extent, LT-IIaB(5) exhibited serum IgG adjuvant effects. In addition, LT-IIa but not LT-IIaB(5) induced T cell-specific anti-OVA responses, particularly in respect to induction of antigen-specific cytotoxic CD8(+) T cell responses. LT-IIa and LT-IIaB(5) induced differential tissue permeability and local inflammatory reactions after i.d. injection. Of particular interest was the reduced or complete lack of local reactions, such as edema and tissue induration, in mice i.d. inoculated with LT-IIa and LT-IIaB(5), respectively, compared with mice immunized with LT-I. In conclusion, the present results show that LT-IIa and, to a lesser extent, LT-IIaB(5) exert adjuvant effects when they are delivered via the i.d. route. In addition, the low inflammatory effects of LT-IIa and LT-IIaB(5) in comparison to those of LT-I support the usefulness of LT-IIa and LT-IIaB(5) as parenterally delivered vaccine adjuvants.

Myeloperoxidase as Inflammatory Marker of Periodontal Disease: Experimental Study in Rats

Rationale: Previous studies have used myeloperoxidase (MPO) as an inflammatory marker to estimate the accumulation of neutrophils in inflamed regions. Objective: The aim of this experimental study was to quantify the levels of MPO related to experimental periodontal disease in rats. Methods: Periodontal disease was induced in a group of rats using placement of a ligature around molar teeth. A group of rats without ligature placement served as a control. Measurements were made on the 3rd, 7th, 15th and 30th day from baseline. Gingival tissues were taken for quantification of MPO levels by ELISA. Results: The rats with induced periodontal disease showed statistically higher MPO levels (p 0.05) when compared to control rats. A significant increase in the levels of MPO released on days 7 and 30 was observed, with higher levels in the group with induced periodontitis. Conclusion: The levels of MPO were found to be higher in rats with induced periodontal disease, confirming the hypothesis that MPO may serve as an inflammatory marker for periodontitis.

Maximal inflammatory response benefits syngeneic skin graft acceptance

Objective: We investigated the influence of acute inflammation in skin isograft acceptance. Methods: Two mouse lines selected for maximal (AIR(MAX)) or minimal inflammatory response (AIR(MIN)) were transplanted with syngeneic skin. Cellular infiltrates and cytokine production were measured 1, 3, 7 or 14 days post-transplantation. The percentage of CD4(+) CD25(+) Foxp3(+) cells in the lymph nodes was also evaluated. Results: Grafts were totally accepted in 100% of AIR(MAX) and in 26% of AIR(MIN) mice. In the latter, partial acceptance was observed in 74% of the animals. Emigrated cells were basically PMN and were enhanced in AIR(MAX) transplants. IL-10 production by graft infiltrating cells showed no interline differences. IFN-gamma was increased in AIR(MIN) grafts at day 14 and lower percentages of CD4(+)CD25(+)Foxp3(+) cells in the lymph nodes were observed in these mice. Conclusions: Our data suggest that differences in graft acceptance might be due to a lack of appropriate regulation of the inflammatory response in AIR(MIN) mice compromising the self/non-self recognition.

Innate immunity to Paracoccidioides brasiliensis infection

Innate immunity is based in pre-existing elements of the immune system that directly interact with all types of microbes leading to their destruction or growth inhibition. Several elements of this early defense mechanism act in concert to control initial pathogen growth and have profound effect on the adaptative immune response that further develops. Although most studies in paracoccidioidomycosis have been dedicated to understand cellular and humoral immune responses, innate immunity remains poorly defined. Hence, the main purpose of this review is to present and discuss some mechanisms of innate immunity developed by resistant and susceptible mice to Paracoccidioides brasiliensis infection, trying to understand how this initial host-pathogen interface interferes with the protective or deleterious adaptative immune response that will dictate disease outcome. An analysis of some mechanisms and mediators of innate immunity such as the activation of complement proteins, the microbicidal activity of natural killer cells and phagocytes, the production of inflammatory eicosanoids, cytokines, and chemokines among others, is presented trying to show the important role played by innate immunity in the host response to P. brasiliensis infection.

Diruthenium(II, III) complexes of ibuprofen, aspirin, naproxen and indomethacin non-steroidal anti-inflammatory drugs: Synthesis, characterization and their effects on tumor-cell proliferation

[Ru-2(dNSAID)(4)Cl] and novel [Ru-2(dNSAID)(4)(H2O)(2)]PF6 complexes, where dNSAID = deprotonated carboxylate from the non-steroidal anti-inflammatory drugs (NSIDs), respectively: ibuprofen, Hibp (1) and aspirin, Hasp (2); naproxen, Hnpx (3) and indomethacin, Hind (4), have been prepared and characterized by optical spectroscopic methods. All of the compounds exhibit mixed valent Ru-2(II, III) cores where metal-metal bonds are stabilized by four drug-carboxylate bridging ligands in paddlewheel type structures. The diruthenium complexes and their parent NSAIDs showed no significant effects for Hep2 human larynx or T24/83 human bladder tumor. In contrast, the coordination of Ru-2(II,III) core led to synergistic effects that increased significantly the inhibition of C6 rat glioma proliferation in relation to the organic NSAIDs naproxen and ibuprofen, The possibility that the complexes Ru-2-ibp and Ru-2-npx may exert effects (anti-angiogenic and anti-matrix metalloprotease) that are similar to those exhibited by NAMI-A opens new horizons for in vivo C6 glioma model studies. (C) 2007 Elsevier Ltd. All rights reserved.

Non-steroidal anti-inflammatory drugs may modulate the protease activity of Candida albicans

The phenotypic pressure exerted by non-steroidal anti-inflammatory drugs (NSAIDs) on autochthonous and pathogenic microbiota remains sparsely known. In this study, we investigated if some NSAIDs increment or diminish the secretion of aspartyl-proteases (Sap) by Candida albicans grown under different phenotypes and oxygen availability using a set of SAP knock-out mutants and other set for genes (EFG1 and CPH1) that codify transcription factors involved in filamentation and protease secretion. Preconditioned cells were grown under planktonic and biofilm phenotypes, in normoxia and anoxia, in the presence of plasma concentrations of acetylsalicylic acid, diclofenac, indomethacin, nimesulide, piroxicam, ibuprofen, and acetaminophen. For diclofenac, indomethacin, nimesulide, and piroxicam the secretion rates of Sap by SAP1-6, EFG1. and CPH1 mutants were similar or, even, inferior to parental wildtype strain. This suggests that neither Sap 1-6 isoenzymes nor Efg1/Cph1 pathways may be entirely responsible for protease release when exposed to these NSAIDs. Ibuprofen and acetaminophen enhanced Sap secretion rates in three environmental conditions (normoxic biofilm, normoxic planktonic and anoxic planktonic). In other hand, aspirin seems to reduce the Sap-related pathogenic behavior of candidal biofilms. Modulation of Sap activity may occur according to candidal phenotypic state, oxygen availability, and type of NSAID to which the cells are exposed. (C) 2010 Elsevier Ltd. All rights reserved.

Bradykinin inducible receptor is essential to lipopolysaccharide-induced acute lung injury in mice

Lipopolysaccharides from gram-negative bacteria are amongst the most common causative agents of acute lung injury, which is characterized by an inflammatory response, with cellular infiltration and the release of mediators/cytokines. There is evidence that bradykinin plays a role in lung inflammation in asthma but in other types of lung inflammation its role is less clear. In the present study we evaluated the role of the bradykinin B(1) receptor in acute lung injury caused by lipopolysaccharide inhalation and the mechanisms behind bradykinin actions participating in the inflammatory response. We found that in C57BI/6 mice, the bradykinin B(1) receptor expression was up-regulated 24 h after lipopolysaccharide inhalation. At this time, the number of cells and protein concentration were significantly increased in the bronchoalveolar lavage fluid and the mice developed airway hyperreactivity to methacholine. In addition, there was an increased expression of tumor necrosis factor-alpha, interleukin-1 beta and interferon-gamma and chemokines (monocytes chemotactic protein-1 and KC) in the bronchoalveolar lavage fluid and in the lung tissue. We then treated the mice with a bradykinin B, receptor antagonist, R-954 (Ac-Orn-[Oic(2), alpha-MePhe(5), D-beta Nal(7), Ile(8)]desArg(9)-bradykinin), 30 min after lipopolysaccharide administration. We observed that this treatment prevented the airway hyperreactivity as well as the increased cellular infiltration and protein content in the bronchoalveolar lavage fluid. Moreover, R-954 inhibited the expression of cytokines/chemokines. These results implicate bradykinin, acting through B(1) receptor, in the development of acute lung injury caused by lipopolysaccharide inhalation. (C) 2010 Elsevier B.V. All rights reserved.

Anti-inflammatory effect of atorvastatin ameliorates insulin resistance in monosodium glutamate-treated obese mice

Considering that inflammation contributes to obesity-induced insulin resistance and that statins have been reported to have other effects beyond cholesterol lowering, the present study aimed to it whether atorvastatin treatment has anti-inflammatory action in white adipose tissue of obese mice, consequently improving insulin sensitivity. Insulin sensitivity in vivo (by insulin tolerance test); metabolic-hormonal profile; plasma tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and adiponectin; adipose tissue immunohistochemistry; glucose transporter (GLUT) 4; adiponectin; INF-alpha; IL-1 beta; and IL-6 gene expression; and I kappa B kinase (IKK)-alpha/beta activity were assessed in 23-week-old monosodium glutamate induced obese mice untreated or treated with atorvastatin for 4 weeks. Insulin-resistant obese mice had increased plasma triglyceride, insulin, TNF-alpha, and IL-6 plasma levels. Adipose tissue of obese animals showed increased macrophage infiltration, IKK-alpha (42%, P < .05) and IKK-beta (73%, P < .05) phosphorylation, and INF-alpha and IL-6 messenger RNA (mRNA) (similar to 15%, P < .05) levels, and decreased GLUT4 mRNA and protein (30%, P < .05) levels. Atorvastatin treatment lowered cholesterol, triglyceride, insulin, INF-alpha, and IL-6 plasma levels, and restored whole-body insulin sensitivity. In adipose tissue, atorvastatin decreased macrophage in and normalized IKK-alpha/beta phosphorylation; INF-alpha, IL-6, and GLUT4 mRNA; and GLUT4 protein to control levels. The present findings demonstrate that atorvastatin has anti-inflammatory effects on adipose tissue of obese mice, which may be important to its local and whole-body insulin-sensitization effects. (C) 2010 Published by Elsevier Inc.