Oral Squamous Cell Carcinoma Lipid Evaluation in Gingiva Tissue Stored in TRIzol via Shotgun Lipidomics and MALDI Mass Spectrometry Imaging.

Oral squamous cell carcinoma (OSCC) is the prevalent type of oral cavity cancer, requiring precise, accurate, and affordable diagnosis to identify the disease in early stages, Comprehending the differences in lipid profiles between healthy and cancerous tissues encompasses great relevance in identifying biomarker candidates and enhancing the odds of successful cancer treatment. Therefore, the present study evaluates the analytical performance of simultaneous mRNA and lipid extraction in gingiva tissue from healthy patients and patients diagnosed with OSCC preserved in TRIzol reagent. The data was analyzed by partial least-squares discriminant analysis (PLS-DA) and confirmed via matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). The lipid extraction in TRIzol solution was linear in a range from 330 to 2000 ng mL-1, r2 > 0.99, intra and interday precision and accuracy <15%, and absolute recovery values ranging from 90 to 110%. The most important lipids for tumor classification were evaluated by MALDI-MSI, revealing that the lipids responsible for distinguishing the OSCC group are more prevalent in the cancerous tissue in contrast to the healthy group. The results exhibit the possibilities to do transcriptomic and lipidomic analyses in the same sample and point out important candidates related to the presence of OSCC.

Anandamide reduces the migration of lymphocytes to the intestine by CB2 activation and reduces TNF-α in the target organs, protecting mice from graft-versus-host disease.

Graft-versus-host disease (GVHD) is a serious inflammatory illness that often occurs as a secondary complication of bone marrow transplantation. Current therapies have limited effectiveness and fail to achieve a balance between inflammation and the graft-versus-tumor effect. In this study, we investigate the effects of the endocannabinoid anandamide on the complex pathology of GVHD. We assess the effects of an irreversible inhibitor of fatty acid amine hydrolase or exogenous anandamide and find that they increase survival and reduce clinical signs in GVHD mice. In the intestine of GVHD mice, treatment with exogenous anandamide also leads to a reduction in the number of CD3+, CD3+CD4+, and CD3+CD8+ cells, which reduces the activation of CD3+CD4+ and CD3+CD8+ cells, as assessed by enhanced CD28 expression, a T cell co-stimulatory molecule. Exogenous AEA was also able to reduce TNF-α and increase IL-10 in the intestine of GVHD mice. In the liver, exogenous AEA reduces injury, TNF-α levels, and the number of CD3+CD8+ cells. Interestingly, anandamide reduces Mac-1α, which lowers the adhesion of transplanted cells in mesenteric veins. These effects are mimicked by JWH133-a CB2 selective agonist-and abolished by treatment with a CB2 antagonist. Furthermore, the effects caused by anandamide treatment on survival were related to the CB2 receptor, as the CB2 antagonist abolished it. This study shows the critical role of the CB2 receptor in the modulation of the inflammatory response of GVHD by treatment with anandamide, the most prominent endocannabinoid.

Polyunsaturated fatty acids alter the formation of lipid droplets and eicosanoid production in Leishmania promastigotes

BACKGROUND The knowledge about eicosanoid metabolism and lipid droplet (LD) formation in the Leishmania is very limited and new approaches are needed to identify which bioactive molecules are produced of them. OBJECTIVES Herein, we compared LDs and eicosanoids biogenesis in distinct Leishmania species which are etiologic agents of different clinical forms of leishmaniasis. METHODS For this, promastigotes of Leishmania amazonensis, L. braziliensis and L. infantum were stimulated with polyunsaturated fatty acids (PUFA) and LD and eicosanoid production was evaluated. We also compared mutations in structural models of human-like cyclooxygenase-2 (GP63) and prostaglandin F synthase (PGFS) proteins, as well as the levels of these enzymes in parasite cell extracts. FINDINGS PUFAs modulate the LD formation in L. braziliensis and L. infantum. Leishmania spp with equivalent tissue tropism had same protein mutations in GP63 and PGFS. No differences in GP63 production were observed among Leishmania spp, however PGFS production increased during the parasite differentiation. Stimulation with arachidonic acid resulted in elevated production of hydroxyeicosatetraenoic acids compared to prostaglandins. MAIN CONCLUSIONS Our data suggest LD formation and eicosanoid production are distinctly modulated by PUFAS dependent of Leishmania species. In addition, eicosanoid-enzyme mutations are more similar between Leishmania species with same host tropism.

Physical activity in the post-COVID-19: AEROBICOVID project design and perspectives / Atividade física no pós-COVID-19: escopo do projeto AEROBICOVID e suas perspectivas

During the COVID-19 pandemic, several late-onset impairments have been observed, affecting the health and functionality of those involved. On the other hand, lower SARS-CoV-2 infection rates and severity of symptoms were observed in high-altitude cities. In this sense, the AEROBICOVID project was developed with the hypothesis that exercise would be an important opportunity for health improvement and that hypoxia would promote additional benefits in the recovery process. The cohort was about 84 participants with approximately 30 days since the COVID-19 symptoms recovery, 25 in the control group, and 59 divided into three moderate physical training groups. The project had good results in teaching, research, and extension, but also faced difficulties in operationalization. This experience is the basis for future proposals through an extension project at the University of São Paulo and in a Family Health Unit, besides a research project that will develop a new low-cost hypoxia technology (AU)

Durante a pandemia de COVID-19 estão sendo observados vários efeitos tardios, afetando a saúde e a funcionalidade dos acometidos. Por outro lado, foram observadas menores taxas de infecção pelo SARS-CoV-2 e gravidade dos sintomas em cidades de elevada altitude. Neste sentido, o projeto AEROBICOVID foi desenvolvido com a hipótese de que o exercício seria uma proposta importante para a melhoria da saúde e que a hipóxia promoveria benefícios adicionais no processo de recuperação. Participaram 84 pessoas com aproximadamente 30 dias desde a recuperação dos sintomas da COVID-19, 25 no grupo de controle e 59 divididos em três grupos de treinamento físico moderado. O projeto teve bons resultados no ensino, pesquisa e extensão, mas também enfrentou dificuldades na operacionalização. Estas experiências são a base para propostas futuras através de um projeto de extensão na Universidade de São Paulo e em uma Unidade de Saúde da Família, além de um projeto de pesquisa que desenvolverá uma nova tecnologia de hipóxia de baixo custo (AU)

Bioactive Lipids as Chronic Myeloid Leukemia's Potential Biomarkers for Disease Progression and Response to Tyrosine Kinase Inhibitors.

Chronic myelogenous leukemia (CML) is a myeloproliferative neoplasm that expresses the Philadelphia chromosome and constitutively activated Bcr-Abl tyrosine kinase in hematopoietic progenitor cells. Bcr-Abl tyrosine-kinase inhibitors (TKI) do not definitively cure all CML patients. The efficacy of TKI is reduced in CML patients in the blastic phase-the most severe phase of the disease-and resistance to this drug has emerged. There is limited knowledge on the underlying mechanisms of disease progression and resistance to TKI beyond BCR-ABL1, as well as on the impact of TKI treatment and disease progression on the metabolome of CML patients. The present study reports the metabolomic profiles of CML patients at different phases of the disease treated with TKI. The plasma metabolites from CML patients were analyzed using liquid chromatography, mass spectrometry, and bioinformatics. Distinct metabolic patterns were identified for CML patients at different phases of the disease and for those who were resistant to TKI. The lipid metabolism in CML patients at advanced phases and TKI-resistant patients is reprogrammed, as detected by analysis of metabolomic data. CML patients who were responsive and resistant to TKI therapy exhibited distinct enriched pathways. In addition, ceramide levels were higher and sphingomyelin levels were lower in resistant patients compared with control and CML groups. Taken together, the results here reported established metabolic profiles of CML patients who progressed to advanced phases of the disease and failed to respond to TKI therapy as well as patients in remission. In the future, an expanded study on CML metabolomics may provide new potential prognostic markers for disease progression and response to therapy.

M1 and M2 macrophages phenotypes modulation after stimuli with materials used in endodontic treatment.

The aim of this study was to evaluate the M1 and M2 macrophage modulation after stimuli with different materials used during endodontic treatment. In bone marrow-derived macrophage cell culture, from males C57BL/6 wild-type (WT) mice, gene expression analysis of markers to M1 and M2 macrophages was performed by qRT-PCR (Cxcl10, CxCL9, iNOS, Arg1, Chil3, Retnla and MRC1) and cytokine quantification by Luminex® (GM-CSF, IL-10, IL-6, IL-1ß and TNF-α) after exposure to the five endodontic sealers: AH Plus, Sealapex Xpress, Endosequence BC Sealer, BioRoot RCS and a calcium hydroxide-based paste. For normal values, ANOVA test was used, followed by Tukey post-test. For non-normal values, the Kruskall-Wallis test was used. BioRootTM RCS and EndoSequence BC SealerTM stimulated the highest expression of markers for M1 macrophages, while calcium hydroxide-based paste stimulated the lowest expression of these gene markers. For M2 protein markers, BioRootTM RCS presented the highest stimulation while calcium hydroxide-based paste also presented the lowest stimulation. It was concluded that all the evaluated filling materials increased the genetic expression of pro- and anti-inflammatory markers: TNF-α and IL-10 respectively. The others proinflammatory mediators showed differences against the filling materials. However, this process did not induce the inflammatory response polarization, resulting in a hybrid macrophage.

M1 and M2 macrophages phenotypes modulation after stimuli with materials used in endodontic treatment

Abstract The aim of this study was to evaluate the M1 and M2 macrophage modulation after stimuli with different materials used during endodontic treatment. In bone marrow-derived macrophage cell culture, from males C57BL/6 wild-type (WT) mice, gene expression analysis of markers to M1 and M2 macrophages was performed by qRT-PCR (Cxcl10, CxCL9, iNOS, Arg1, Chil3, Retnla and MRC1) and cytokine quantification by Luminex® (GM-CSF, IL-10, IL-6, IL-1β and TNF-α) after exposure to the five endodontic sealers: AH Plus, Sealapex Xpress, Endosequence BC Sealer, BioRoot RCS and a calcium hydroxide-based paste. For normal values, ANOVA test was used, followed by Tukey post-test. For non-normal values, the Kruskall-Wallis test was used. BioRootTM RCS and EndoSequence BC SealerTM stimulated the highest expression of markers for M1 macrophages, while calcium hydroxide-based paste stimulated the lowest expression of these gene markers. For M2 protein markers, BioRootTM RCS presented the highest stimulation while calcium hydroxide-based paste also presented the lowest stimulation. It was concluded that all the evaluated filling materials increased the genetic expression of pro- and anti-inflammatory markers: TNF-α and IL-10 respectively. The others proinflammatory mediators showed differences against the filling materials. However, this process did not induce the inflammatory response polarization, resulting in a hybrid macrophage.

Resumo O objetivo deste estudo foi avaliar a modulação dos macrófagos M1 e M2 após estímulos com diferentes materiais utilizados durante o tratamento endodôntico. Em cultura de células de macrófagos derivados da medula óssea de camundongos machos C57BL/6 wild-type (WT), após a exposição à cinco cimentos endodônticos: AH Plus, Sealapex Xpress, Endosequence BC Sealer, BioRoot RCS e pasta à base de hidróxido de cálcio foi realizada a análise da expressão gênica dos marcadores para macrófagos M1 e M2 por qRT-PCR (Cxcl10, CxCL9, iNOS, Arg1, Chil3, Retnla e MRC1) e quantificação de citocinas por Luminex® (GM -CSF, IL-10, IL-6, IL-1β e TNF-α). Para valores normais, foi utilizado o teste ANOVA, seguido do pós-teste de Tukey. Para valores não normais, foi utilizado o teste de Kruskall-Wallis. BioRootTM RCS e EndoSequence BC SealerTM estimularam maior expressão de marcadores para macrófagos M1, enquanto a pasta à base de hidróxido de cálcio estimulou expressão mais baixa desses marcadores gênicos. Para o marcador de proteínas para M2, BioRootTM RCS apresentou a maior estimulação, enquanto a pasta à base de hidróxido de cálcio também apresentou menor estimulação. Concluiu-se que os materiais obturadores avaliados aumentaram a expressão genética de marcadores pró- e anti-inflamatórios: TNF-α e IL-10 respectivamente. Os demais marcadores pró inflamatórios mostraram diferenças em relação aos materiais obturadores. No entanto, esse processo não induziu a polarização da resposta inflamatória, resultando em um macrófago híbrido.

Multifaceted effect of caffeic acid against Streptococcus mutans infection: microbicidal and immunomodulatory agent in macrophages.

The aim of the present study was to investigate the effects of caffeic acid in the interface between the antimicrobial and anti-inflammatory function in macrophage response against S. mutans. S. mutans (108 cfu/mL) were incubated with caffeic acid to determinate the half-maximal inhibitory concentration (IC50) and macrophage cells were incubated with caffeic acid to determinate cell viability and toxicity. Anti-inflammatory effects were measured by nitrite accumulation, TNF-α and PGE2 production, and NF-kB phosphorylation, and S. mutans survival following internalization by macrophages was investigated. We found that caffeic acid presented antimicrobial activity against S. mutans (IC50 = 2.938 ± 0.1225 mM) without exerting cytotoxicity. Caffeic acid inhibited nitrite, TNF-α and PGE2 production by the NF-kB dependent pathway, indicating an immunomodulatory property. Caffeic acid also contributed to macrophage bacteria clearance activity. In summary, caffeic acid presented antimicrobial activity against S. mutans and anti-inflammatory effects in macrophages.

Photosensitizers attenuate LPS-induced inflammation: implications in dentistry and general health.

Antimicrobial photodynamic therapy (aPDT) is a complementary therapeutic modality for periodontal and endodontic diseases, in which Gram-negative bacteria are directly involved. Currently, there are few evidences regarding the effects of aPDT on bacterial components such as lipopolysaccharide (LPS) and it would represent a major step forward in the clinical use of this therapy. In this context, this study aimed to evaluate the efficacy of different photosensitizers (PSs) used in aPDT in LPS inhibition. Four PSs were used in this study: methylene blue (MB), toluidine blue (TBO), new methylene blue (NMB), and curcumin (CUR). Different approaches to evaluate LPS interaction with PSs were used, such as spectrophotometry, Limulus amebocyte lysate (LAL) test, functional assays using mouse macrophages, and an in vivo model of LPS injection. Spectrophotometry showed that LPS decreased the absorbance of all PSs used, indicating interactions between the two species. LAL assay revealed significant differences in LPS concentrations upon pre-incubation with the different PSs. Interestingly, the inflammatory potential of LPS decreased after previous treatment with the four PSs, resulting in decreased secretion of inflammatory cytokines by macrophages. In vivo, pre-incubating curcumin with LPS prevented animals from undergoing septic shock within the established time. Using relevant models to study the inflammatory activity of LPS, we found that all PSs used in this work decreased LPS-induced inflammation, with a more striking effect observed for NMB and curcumin. These data advance the understanding of the mechanisms of LPS inhibition by PSs.

The ethanolic extract of Terminalia argentea Mart. & Zucc. bark reduces the inflammation through the modulation of cytokines and nitric oxide mediated by the downregulation of NF-κB.

ETHNOPHARMACOLOGICAL RELEVANCE: Terminalia argentea Mart. & Zucc. (Combretaceae), popularly known as "capitão do campo", is native from the Brazilian cerrado, which is used in folk medicine to treat inflammatory diseases. AIM OF THE STUDY: We aimed to investigate the anti-inflammatory effects, toxicity and mechanisms of action regarding the use of the hydroalcoholic extract of T. argentea bark. MATERIALS AND METHODS: Toxicity was determinate in vitro using the macrophage lineage J774.1 without LPS. Cells were treated with 0.5; 2; 8; 32 and 125 µg/mL of the plant extract. Cell viability was assessed by MTT colorimetric assay. The production of nitrite and cytokines was also determined in the supernatants. A NF-κB reporter assay using RAW macrophages was employed to elucidate the impact of the plant extract on the expression of such molecule. In mice, toxicity was assessed by orally given an intermediate to high concentration of the plant extract on a single dose (1000 or 5000 mg/kg) or low and intermediate doses (300 or 1000 mg/kg) twice daily for 14 days. Blood samples were collected for biochemical analysis. The anti-inflammatory activity was assessed using the air-pouch model with or without pre-inoculation with the inflammatory stimuli LPS (0.5 µg/mL), followed by treatment with plant extract at 5, 60 or 300 mg/kg administered in the air pouch (subcutaneous injection). After 4 h, mice were euthanized and the air pouches washed with 2 mL heparinized PBS (10 IU/mL). Then, the local production in the air pouch wash of cytokines, total proteins and leukocytes was assessed. RESULTS: No signals of toxicity were observed either in cells or mice. Regardless the concentration used in vitro, the extract exhibited a significant anti-inflammatory activity, as perceived by the reduction of the inflammatory cytokines IL-1ß, TNF-α and IL-6 and nitrites on cell supernatants. This was concomitant with a downregulation in NF-κB and elevated levels of IL-10. In mice, similar effects were observed, especially when the plant extract was given at 300 mg/kg, inhibiting the release of IL-1ß, TNF-α, IL-6 and proteins, as well as increasing the release of IL-10. CONCLUSIONS: Altogether, our results demonstrated that the hydroalcoholic extract of T. argentea bark has anti-inflammatory activity without inducing toxicity in cells or living animals. This activity seems to be chiefly influenced by a downregulation in NF-κB, inflammatory cytokines and production of nitrite along with augmented concentration of IL-10.

Phospholipids modifications in human hepatoma cell lines (HepG2) exposed to silver and iron oxide nanoparticles.

Metallic nanoparticles such as silver (Ag NPs) and iron oxide (Fe3O4 NPs) nanoparticles are high production volume materials due to their applications in various consumer products, and in nanomedicine. However, their inherent toxicities to human cells remain a challenge. The present study was aimed at combining lipidomics data with common phenotypically-based toxicological assays to gain better understanding into cellular response to Ag NPs and Fe3O4 NPs exposure. HepG2 cells were exposed to different concentrations (3.125, 6.25, 12.5, 25, 50 and 100 µg/ml) of the nanoparticles for 24 h, after which they were assayed for toxic effects using toxicological assays like cytotoxicity, mutagenicity, apoptosis and oxidative stress. The cell membrane phospholipid profile of the cells was also performed using shotgun tandem mass spectrometry. The results showed that nanoparticles exposure resulted in concentration-dependent cytotoxicity as well as reduced cytokinesis-block proliferation index (CBPI). Also, there was an increase in the production of ROS and superoxide anions in exposed cells compared to the negative control. The lipidomics data revealed that nanoparticles exposure caused a modulation of the phospholipidome of the cells. A total of 155 lipid species were identified, out of which the fold changes of 23 were significant. The high number of differentially changed phosphatidylcholine species could be an indication that inflammation is one of the major mechanisms of toxicity of the nanoparticles to the cells.

Investigation of the Involvement of the Endocannabinoid System in TENS-Induced Antinociception.

Transcutaneous electrical nerve stimulation (TENS) promotes antinociception by activating the descending pain modulation pathway and consequently releasing endogenous analgesic substances. In addition, recent studies have shown that the endocannabinoid system controls pain. Thus, the present study investigated the involvement of the endocannabinoid system in TENS-induced antinociception of cancer pain using a cancer pain model induced by intraplantar (i.pl.) injections of Ehrlich tumor cells in male Swiss mice. Low- and high-frequency TENS was applied for 20 minutes to the mice's paws, and to investigate the involvement of the endocannabinoid system were used the N-(peperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pitazole-3-carboixamide (AM251), a cannabinoid CB1 receptor antagonist and (5Z,8Z,11Z,14Z)-5,8,11,14-eicosatetraenyl-methylester phosphonofluoridic acid (MAFP), an inhibitor of the endocannabinoid metabolizing enzyme fatty acid amide hydrolase, injected by via i.pl., intrathecal (i.t.), and intradorsolateral periaqueductal gray matter (i.dl.PAG). Furthermore, liquid chromatography-tandem mass spectrometry, western blot, and immunofluorescence assays were used to evaluate the endocannabinoid anandamide levels, cannabinoid CB1 receptor protein levels, and cannabinoid CB1 receptor immunoreactivity, respectively. Low- and high-frequency TENS reduced the mechanical allodynia induced by Ehrlich tumor cells and this effect was reversed by AM251 and potentiated by MAFP at the peripheral and central levels. In addition, TENS increased the endocannabinoid anandamide levels and the cannabinoid CB1 receptor protein levels and immunoreactivity in the paw, spinal cord, and dorsolateral periaqueductal gray matter. These results suggest that low- and high-frequency TENS is effective in controlling cancer pain, and the endocannabinoid system is involved in this effect at both the peripheral and central levels. PERSPECTIVE: TENS is a nonpharmacological strategy that may be used to control cancer pain. Identification of a new mechanism involved in its analgesic effect could lead to the development of clinical studies as well as an increase in its application, lessening the need for pharmacological treatments.

Eicosanoid pathway on host resistance and inflammation during Mycobacterium tuberculosis infection is comprised by LTB4 reduction but not PGE2 increment.

The functions of eicosanoids, a family of potent biologically active lipid mediators, are not restricted to inflammatory responses and they also act as mediators of the pathogenesis process. However, the role of eicosanoids in tuberculosis remains controversial. To investigate the specific role of LTB4 in Mycobacterium tuberculosis (Mtb) infection, we used 5-lipoxygenase-deficient (5-LO-/-) mice and WT (sv129) mice inoculated intranasally with LTB4 (encapsulated in PLGA microspheres). We showed that deficiency of the 5-LO pathway was related to resistance to Mtb infection. LTB4 inoculation increased susceptibility to Mtb in 5-LO-/- mice but not in WT mice, resulting in worsening of lung inflammation and tissue damage. In infected WT mice, most supplementary LTB4 was metabolized to the inactive form 12-oxo-LTB4 in the lung. A high amount of PGE2 was detected during Mtb infection, and pharmacological inhibition of COX-2 induced a significant reduction of bacterial load and an improved innate immune response in the lungs, independently of baseline LTB4 levels. COX-2 inhibition with celecoxib significantly reduced PGE2 levels, enhanced IFN-γ production and NO release, and increased macrophage phagocytosis of Mtb. The results suggest that a balance between PGE2/LTB4 is essential in the pathogenesis process of tuberculosis to prevent severe inflammation. Moreover, optimal levels of PGE2 are required to induce an effective innate response in the early phase of Mtb infection. Thus, pharmacological modulation of eicosanoid production may provide an important host-directed therapy in tuberculosis.

The inhibition of 5-Lipoxygenase (5-LO) products leukotriene B4 (LTB4) and cysteinyl leukotrienes (cysLTs) modulates the inflammatory response and improves cutaneous wound healing.

To analyze the participation of the enzyme 5-lipoxygenase (5-LO) in skin repair, WT wounds were compared to those in 5-LO deficient mice (5-LO-/-), which presented faster closure and reduced inflammatory infiltrate in the skin, together with increased CD4 regulatory T cells markers in the draining lymph nodes. The 5-LO-/- wounds also had diminished TNF-α, CCL11, CCL7, CCL2, CXCL9, CCR1 and CXCR2 mRNA expression in the lesions, besides differential extracellular matrix remodeling. Furthermore, when cysteinyl leukotriene (cysLT) and leukotriene (LTB4) receptors were antagonized in WT mice, there was a remarkable reduction in TNF-α expression and faster skin healing, similarly to the findings in 5-LO-/- animals. Finally, our results suggested that 5-LO products, in special cysLT and LTB4, underline skin inflammation that follows skin injury and their neutralization may be an important strategy to improve cutaneous healing.

Successful and failed mini-implants: microbiological evaluation and quantification of bacterial endotoxin

Abstract Objectives Using two groups of mini-implants (successful and failed) the objectives of this in vivo study were: to evaluate the microbial contamination by the checkerboard DNA-DNA hybridization technique and to quantify the bacterial endotoxin by the limulus amebocyte lysate assay. Material and Methods The 15 successful and 10 failed mini-implants (1.6 mm diameter × 7.0 or 9.0 mm long), placed in the maxilla and/or mandible, were obtained from 15 patients undergoing orthodontic treatment. Data were analyzed statistically by the Wilcoxon rank-sum test using the SAS software (a=0.05). Results All 40 microbial species were detected in both groups of mini-implants, with different frequencies. No differences were observed between the groups with respect to microbial complexes (blue, purple, yellow, green, orange, red and other species) and endotoxin quantification (p>0.05). Conclusion Neither microbial contamination nor endotoxin quantification was determinant for the early loss of stability of the mini-implants.

Hyaluronidase decreases neutrophils infiltration to the inflammatory site.

OBJECTIVE: To evaluate the in vivo anti-inflammatory potential of bovine hyaluronidase (HYAL) using two different models of acute inflammation. METHODS: Air pouches were produced in the dorsal subcutaneous of mice and injected with phosphate saline solution or HYAL. The antiinflammatory action of HYAL was evaluated in carrageenan (Cg)-inflamed air pouches. After 4 and 24 h the cellular influx, protein exudation, cytokines and lipid mediators were evaluated. The action of HYAL on the rolling and adhesion of leukocytes was investigated in the LPS-stimulated mesenteric microcirculation by intravital microscopic. RESULTS: Treatment with HYAL reduced the cellular influx and protein exudation in non-inflamed and inflamed air pouches. HYAL treatment of Cg-inflamed air pouch reduced the production of tumor necrosis factor-alpha (TNF-α), interleukin-8 (IL-8), leukotriene B4 (LTB4) and LTC4, whereas prostaglandins E2 (PGE2) and D2 (PGD2) concentrations were unchanged. Histological analyses showed that HYAL administration diminished cell infiltration in the air-pouch lining. In LPS-stimulated mesenteric microcirculation, HYAL usage decreased rolling and adhesion of leukocytes, but did not affect the blood vessels diameters. CONCLUSION: The results demonstrate that HYAL inhibited cellular recruitment, edema formation and pro-inflammatory mediators production, resulting in decreased adherence of leukocytes to blood vessels and tissue infiltration. Our data suggest that HYAL may be considered an effective candidate to ameliorate acute inflammation.

Erythropoietin Exacerbates Inflammation and Increases the Mortality of Histoplasma capsulatum-Infected Mice.

Erythropoietin (EPO) is a key hormone involved in red blood cell formation, but its effects on nonerythroid cells, such as macrophages, have not been described. Macrophages are key cells in controlling histoplasmosis, a fungal infection caused by Histoplasma capsulatum (Hc). Considering that little is known about EPO's role during fungal infections and its capacity to activate macrophages, in this study we investigated the impact of EPO pretreatment on the alveolar immune response during Hc infection. The consequence of EPO pretreatment on fungal infection was determined by evaluating animal survival, fungal burden, activation of bronchoalveolar macrophages, inflammatory mediator release, and lung inflammation. Pretreatment with EPO diminished mononuclear cell numbers, increased the recruitment of F4/80(+)/CD80(+) and F4/80(+)/CD86(+) cells to the bronchoalveolar space, induced higher production of IFN-γ, IL-6, MIP-1α, MCP-1, and LTB4, reduced PGE2 concentration, and did not affect fungal burden. As a consequence, we observed an increase in lung inflammation with extensive tissue damage that might account for augmented mouse mortality after infection. Our results demonstrate for the first time that EPO treatment has a deleterious impact on lung immune responses during fungal infection.

GM-CSF priming drives bone marrow-derived macrophages to a pro-inflammatory pattern and downmodulates PGE2 in response to TLR2 ligands.

In response to pathogen recognition by Toll-like receptors (TLRs) on their cell surface, macrophages release lipid mediators and cytokines that are widely distributed throughout the body and play essential roles in host responses. Granulocyte macrophage colony-stimulating factor (GM-CSF) is important for the immune response during infections to improve the clearance of microorganisms. In this study, we examined the release of mediators in response to TLR2 ligands by bone marrow-derived macrophages (BMDMs) primed with GM-CSF. We demonstrated that when stimulated with TLR2 ligands, non-primed BMDMs preferentially produced PGE(2) in greater amounts than LTB(4). However, GM-CSF priming shifted the release of lipid mediators by BMDMs, resulting in a significant decrease of PGE(2) production in response to the same stimuli. The decrease of PGE(2) production from primed BMDMs was accompanied by a decrease in PGE-synthase mRNA expression and an increase in TNF-α and nitric oxide (NO) production. Moreover, some GM-CSF effects were potentiated by the addition of IFN-γ. Using a variety of TLR2 ligands, we established that PGE(2) release by GM-CSF-primed BMDMs was dependent on TLR2 co-receptors (TLR1, TLR6), CD14, MyD88 and the nuclear translocation of NFκB but was not dependent on peroxisome proliferator-activated receptor-γ (PPAR-γ) activation. Indeed, GM-CSF priming enhanced TLR2, TLR4 and MyD88 mRNA expression and phospho-IκBα formation. These findings demonstrate that GM-CSF drives BMDMs to present a profile relevant to the host during infections.

Febrile response induced by cecal ligation and puncture (CLP) in rats: involvement of prostaglandin E2 and cytokines.

The purpose of the present study was to better understand the events involved in the febrile response induced by cecal ligation and puncture (CLP), a complex infectious process. To this end, we conducted in vivo experiments in rats examining (1) fever development, (2) bacterial number in the infection focus and in blood, (3) peripheral and hypothalamic synthesis of cytokines, (4) hypothalamic and cerebrospinal fluid (CSF) synthesis of prostaglandin E(2) (PGE(2)), (5) the effect of anti-IL-6 antibody on fever, and (6) the effect of celecoxib on fever and hypothalamic synthesis of PGE(2) after CLP induction. We found that CLP promotes fever and animal death depending on the number of punctures. The peak of CLP-induced fever overlapped with the maximal increase in the number of bacteria in the infectious focus and blood, which occurred at 6 and 12 h. The peak of the febrile response also coincided with increased amounts of interleukin (IL)-1ß, IL-6 and IL-10 in the peritoneal exudate and serum; IL-6 in the hypothalamus and PGE(2) in the CSF and predominantly in the hypothalamus. Moreover, intracerebroventricularly injected anti-IL-6 antibody reduced the febrile response while celecoxib reduced the fever and PGE(2) amount in the hypothalamus induced by CLP. Tumor necrosis factor (TNF)-α peaked at 3 h at all sites studied. Conversely, IL-10 concentration decreased in the hypothalamus. These findings show that the peak of CLP-induced fever is accompanied by an increase of bacteria in peritoneal fluid (local infection) and blood; local synthesis of pyrogenic (IL-1ß, IL-6) and antipyretic (IL-10) cytokines and central production of IL-6 and PGE(2), suggesting that these last are the central mediators of this response.

Leukotrienes are upregulated and associated with human T-lymphotropic virus type 1 (HTLV-1)-associated neuroinflammatory disease.

Leukotrienes (LTs) are lipid mediators involved in several inflammatory disorders. We investigated the LT pathway in human T-lymphotropic virus type 1 (HTLV-1) infection by evaluating LT levels in HTLV-1-infected patients classified according to the clinical status as asymptomatic carriers (HACs) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients. Bioactive LTB(4) and CysLTs were both increased in the plasma and in the supernatant of peripheral blood mononuclear cell cultures of HTLV-1-infected when compared to non-infected. Interestingly, CysLT concentrations were increased in HAM/TSP patients. Also, the concentration of plasma LTB(4) and LTC(4) positively correlated with the HTLV-1 proviral load in HTLV-1-infected individuals. The gene expression levels of LT receptors were differentially modulated in CD4(+) and CD8(+) T cells of HTLV-1-infected patients. Analysis of the overall plasma signature of immune mediators demonstrated that LT and chemokine amounts were elevated during HTLV-1 infection. Importantly, in addition to CysLTs, IP-10 was also identified as a biomarker for HAM/TSP activity. These data suggest that LTs are likely to be associated with HTLV-1 infection and HAM/TSP development, suggesting their putative use for clinical monitoring.