Pleural Cavity Of Mice Research Articles

ROCK Inhibition Drives Resolution of Acute Inflammation by Enhancing Neutrophil Apoptosis.

Uncontrolled inflammation leads to tissue damage and it is central for the development of chronic inflammatory diseases and autoimmunity. An acute inflammatory response is finely regulated by the action of anti-inflammatory and pro-resolutive mediators, culminating in the resolution of inflammation and restoration of homeostasis. There are few studies investigating intracellular signaling pathways associated with the resolution of inflammation. Here, we investigate the role of Rho-associated kinase (ROCK), a serine/threonine kinase, in a model of self-resolving neutrophilic inflammatory. We show that ROCK activity, evaluated by P-MYPT-1 kinetics, was higher during the peak of lipopolysaccharide-induced neutrophil influx in the pleural cavity of mice. ROCK inhibition by treatment with Y-27632 decreased the accumulation of neutrophils in the pleural cavity and was associated with an increase in apoptotic events and efferocytosis, as evaluated by an in vivo assay. In a model of gout, treatment with Y-27632 reduced neutrophil accumulation, IL-1β levels and hypernociception in the joint. These were associated with reduced MYPT and IκBα phosphorylation levels and increased apoptosis. Finally, inhibition of ROCK activity also induced apoptosis in human neutrophils and destabilized cytoskeleton, extending the observed effects to human cells. Taken together, these data show that inhibition of the ROCK pathway might represent a potential therapeutic target for neutrophilic inflammatory diseases.

The health hazards of fiber intake

Cancer Carbon nanotubes (CNTs) are used in a variety of commercial applications, from automotive parts to computers. Increased human exposure to these nanomaterials has sparked concerns about possible health risks because CNTs have structural similarities to asbestos, which causes the incurable cancer mesothelioma. A new study in mice does not alleviate these concerns. Chernova et al. delivered either long-fiber asbestos or long-fiber CNTs into the pleural cavity of mice and found that the treatments both induced chronic inflammation and activated the same signaling pathways. By 12 to 20 months after exposure, at least 10% of the mice in each group had developed mesothelioma. These results suggest that CNTs pose health risks similar to those of asbestos and that human exposure to them should be monitored. Curr. Biol. 27 , 3302 (2017).

Beneficial effect of Ageratum conyzoides Linn (Asteraceae) upon inflammatory response induced by carrageenan into the mice pleural cavity

Ethnopharmacological relevanceAgeratum conyzoides Linn (Asteraceae), a tropical plant that is very common in West Africa and some parts of Asia and South America, has been used to treat inflammatory disorders. In Brazil, teas made from A. conyzoides L. are used as anti-inflammatory, analgesic and anti-diarrheic agents. Therefore, it is necessary to study the mechanism of anti-inflammatory action of A. conyzoides L. to support its medicinal use for treating inflammatory conditions. These studies will also support the development of effective pharmacological agents with potent anti-inflammatory properties. Aim of the studyTo evaluate the anti-inflammatory effects of the crude extract (CE), its derived fractions: ethanol (EtOH-F), hexane (HEX-F), ethyl acetate (EtOAc-F) and dichloromethane (DCM-F) and isolated compounds, such as 5′-methoxy nobiletin (MeONOB), 1,2-benzopyrone and eupalestin, which are obtained from the aerial parts of A. conyzoides L. Materials and methodsThese evaluations were performed using an animal model of inflammation induced by carrageenan. The following inflammatory parameters were analysed: leukocyte influx, protein concentration of the exudate, myeloperoxidase (MPO), adenosine deaminase (ADA) and nitric oxide metabolites (NOx) concentrations, interleukin 10 (IL-10), interleukin 17A (IL-17A), interleukin 6 (IL-6), tumor necrosis factor (TNF), interferon gamma (IFN-γ) and phosphorylation of p65 subunit of NF-κB (p-p65 NF-κB), p38 mitogen-activated protein kinases (p-p38 MAPK) were also analysed. ResultsCE, its EtOH-F, HEX-F, EtOAc-F and DCM-F and the isolated compounds, including MeONOB, 1,2-benzopyrone and eupalestin, significantly reduced leukocyte influx, protein concentration of the exudate, MPO, ADA, and NOx concentrations (p<0.05). CE, EtOH-F and isolated compounds significantly reduced IL-17A, IL-6, TNF and IFN-γ levels (p<0.05). CE, EtOH-F and isolated compound 1,2-benzopyrone also increased IL-10 levels (p<0.05). Isolated compounds, MeONOB, 1,2-benzopyrone and eupalestin, reduced p-p65 NF-κB and p-p38 MAPK (p<0.01). ConclusionsThis study demonstrates that A. conyzoides L. exerts its important anti-inflammatory properties by inhibiting leukocyte influx and protein concentration of the exudate, as well as reducing the levels of several pro-inflammatory mediators. The anti-inflammatory action of A. conyzoides L. may be because of the inhibition of p65 NF-κB and MAPK activation by the isolated compounds.

Evaluation of carbon nanotubes functionalized with sodium hyaluronate in the inflammatory processes for oral regenerative medicine applications.

The objectives of this study were to assess the effects of hyaluronic acid (HY), multi-walled carbon nanotubes (MWCNT), and MWCNT functionalized with HY (HY-MWCNT) on the resolution of neutrophilic inflammation in the pleural cavity of LPS-challenged mice and to assess the influence of these materials in the inflammatory process of bone repair of tooth sockets of rats. C57Bl/6 mice were intra-pleurally injected with HY, MWCNT, HY-MWCNT, phosphate-buffered saline (PBS), or LPS. The animals were euthanized after 8 and 24h, and cells were harvested for total and differential cell counting. The tooth sockets of Wistar rats were filled with HY, MWCNT, HY-MWCNT, or blood clot (control). After 1, 3, and 7days, histological and morphometric analyses evaluated the number of cell nuclei and blood vessels, and bone trabeculae formation in the sockets. Myeloperoxidase (MPO) activity quantified neutrophil accumulation in the sockets. HY, MWCNT, and HY-MWCNT increased neutrophilic recruitment at 8h and reduced the inflammatory process at 24h in the pleural cavity. Histological and morphometric analyses and MPO activity showed no significant differences in the recruitment of inflammatory cells in the tooth sockets. HY increased the number of blood vessels, and HY and HY-MWCNT increased bone trabeculae formation at 7days of tooth extraction. HY, MWCNT, and HY-MWCNT resolved the neutrophilic inflammation in the pleural cavity of the mice. However, these materials did not modulate the inflammatory process in the early stages of bone repair of the tooth sockets, thereby excluding this action as a possible mechanism by which these biomaterials accelerate bone repair. HY-MWCNT is capable of accelerating bone repair/regeneration without affecting the inflammatory phase during the bone healing process.

Itraconazole can inhibit malignant pleural effusion by suppressing lymphangiogenesis in mice.

The presence of malignant pleural effusion (MPE) indicates a poor prognosis in patients with non-small cell lung cancer (NSCLC). Itraconazole has been identified as a potent inhibitor of endothelial cell proliferation that suppresses angiogenesis; however, its role in the suppression of lymphangiogenesis is still unclear. The aim of this study was to investigate the efficacy of itraconazole for MPE and the mechanism of lymphangiogenesis suppression. Lewis lung carcinoma (LLC) cells were injected into the mouse pleural cavity to establish the MPE mouse model, followed by randomization of the mice into three groups. Each mice was injected with either a high dose of itraconazole (25 mg/kg, H-ITCZ), a low dose of itraconazole (8 mg/kg, L-ITCZ), or 50 μL of hydroxypropyl-β-cyclodextrin (130 mg/mL, H-β-C) into the pleural cavity four times every 3 days. The MPE of the mice was collected and measured with a 1 mL syringe. The vascular endothelial growth factor-C (VEGF-C) expression level in the MPE was detected by enzyme-linked immunosorbent assay (ELISA), while the VEGF-C expression and lymphatic micro vessel density (LMVD) in the tumor tissue was observed by immunohistochemistry (IHC) staining. The number of pleural tumor foci, the volume of pleural effusion, the LMVD and the VEGF-C expression levels in the tumor tissue were significantly reduced in the H-ITCZ-treated group. Our results revealed that itraconazole may play an important role in the MPE mice by suppressing lymphangiogenesis, which demonstrated the usefulness of itraconazole in the treatment of MPE.

Involvement of regional neutrophil apoptosis promotion by ribosomal protein S19 oligomers in resolution of experimental acute inflammation

Isolated peripheral neutrophils spontaneously underwent apoptosis in association with extra-cellular liberation of the monocyte-attracting ribosomal protein S19 (RP S19) oligomers. This apoptosis was prevented by the simultaneous presence of anti-RP S19 antibodies or of a C5a receptor antagonist, but was promoted by supplementing extrinsic RP S19 oligomers. Transformed HL-60 cells to over-produce Gln137Asn-mutant RP S19 were differentiated to neutrophil-like cells. The neutrophil-like cells gained resistance against the spontaneous apoptosis concomitant with the generation of non-functional RP S19 oligomers. When the neutrophil-like cells were intradermally transplanted into mice, the mutant RP S19-producing neutrophils persisted for a long period of time, whereas wild-type RP S19-producing neutrophils underwent apoptosis and were promptly cleared by infiltrated macrophages. When an experimental pleurisy was introduced by injecting carrageenan into the pleural cavity of mice, the inflammation spread slightly to lung parenchyma. When antibodies neutralizing the RP S19 oligomers were simultaneously administrated with carrageenan, the neutrophil infiltration in the lung parenchymal lesion become more severe, occurring as alveolar septal destruction and hemorrhage concomitant with an augmented neutrophil number in the pleural exudate. These results indicate the importance of the RP S19 oligomers and the C5a receptor in neutrophil clearance and acute inflammation resolution.

Establishment of a malignant pleural effusion mouse model with Lewis lung carcinoma cell lines expressing enhanced green fluorescent protein

背景与目的恶性胸腔积液是晚期肺癌预后差的因素之一。本研究拟用Lewis肺癌细胞构建裸鼠恶性胸腔积液模型，从而建立一个良好的动物实验研究平台。方法经胸膜腔接种表达增强型绿色荧光蛋白的Lewis肺癌细胞，建立裸鼠恶性胸腔积液模型。定期解剖小鼠，经小动物活体荧光成像系统观察肿瘤的生长。剩余小鼠定期行胸部CT检查，计算各时间点的成胸水率，并观察建模后裸鼠的生存期和肿瘤转移情况。所有小鼠在解剖时发现有胸水，抽取并计量，同一时间点内获得多份胸水标本，计算其平均体积。利用相关性检验分析胸水体积与肿瘤积分光密度之间的相关性。结果接种后第4天，荧光体视镜下可发现胸膜上有绿色荧光，成瘤率100%。随接种时间延长，肿瘤体积逐渐增加，肿瘤侵及纵隔和肺门淋巴结、对侧胸膜、心包，转移率分别为87%、73%和20%。第7天、第14天和第21天成胸水率分别为13%、46%和53%。小鼠平均生存时间为28.8天，所有胸水均为血性，胸水平均体积在第10天以后逐渐增加，第16天达到峰值（0.5 mL）。胸水体积与积分光密度之间具有相关性（r=0.91, P < 0.000, 1）。结论本研究将表达增强型绿色荧光蛋白的肺癌细胞在显微镜下经胸膜腔接种成功建立肺癌恶性胸腔积液模型，有助于动态观察肿瘤细胞在胸腔内的生物学行为，该模型可应用于肺癌的基础研究及抗肿瘤药物开发。

Proteinase-Activated Receptor-4 Plays a Major Role in the Recruitment of Neutrophils Induced by Trypsin or Carrageenan during Pleurisy in Mice

Background/Aims: The activation of proteinase-activated receptors (PARs) has been implicated in the development of important hallmarks of inflammation, including in vivo leukocyte recruitment. Here, we examined the effects of aprotinin, a potent inhibitor of trypsin proteinase and the kallikrein-kinin system, and the PAR-4 antagonist YPGKF-NH₂ (tcY-NH₂) on neutrophil recruitment in response to carrageenan and trypsin in the pleural cavity of mice. Methods: BALB/c mice were intrapleurally injected with trypsin or PAR-4-activating peptide AY-NH₂, pretreated with aprotinin or tcY-NH₂ (1 µg/cavity) prior to an intrapleural injection of trypsin or carrageenan, or pretreated with leukotriene B₄ antagonist U-75302 (3 µg/cavity) prior to a trypsin injection. The number of infiltrating neutrophils was evaluated after 4 h. Results: PAR-4-activating peptide AY-NH₂ and trypsin-induced neutrophil recruitment was inhibited by aprotinin, tcY-NH₂ or U-75302. Aprotinin and tcY-NH₂ also inhibited neutrophil recruitment induced by carrageenan. Conclusion: These data suggest a key role for PAR-4 in mediating neutrophil recruitment in a mouse model of pleurisy induced by the activity of trypsin or trypsin-like enzymes.

The mechanism of pleural inflammation by long carbon nanotubes: interaction of long fibres with macrophages stimulates them to amplify pro-inflammatory responses in mesothelial cells

Carbon nanotubes (CNT) are high aspect ratio nanoparticles with diameters in the nanometre range but lengths extending up to hundreds of microns. The structural similarities between CNT and asbestos have raised concern that they may pose a similar inhalation hazard. Recently CNT have been shown to elicit a length-dependent, asbestos-like inflammatory response in the pleural cavity of mice, where long fibres caused inflammation but short fibres did not. However the cellular mechanisms governing this response have yet to be elucidated. This study examined the in vitro effects of a range of CNT for their ability to stimulate the release of the acute phase cytokines; IL-1β, TNFα, IL-6 and the chemokine, IL-8 from both Met5a mesothelial cells and THP-1 macrophages. Results showed that direct exposure to CNT resulted in significant cytokine release from the macrophages but not mesothelial cells. This pro-inflammatory response was length dependent but modest and was shown to be a result of frustrated phagocytosis. Furthermore the indirect actions of the CNT were examined by treating the mesothelial cells with conditioned media from CNT-treated macrophages. This resulted in a dramatic amplification of the cytokine release from the mesothelial cells, a response which could be attenuated by inhibition of phagocytosis during the initial macrophage CNT treatments. We therefore hypothesise that long fibres elicit an inflammatory response in the pleural cavity via frustrated phagocytosis in pleural macrophages. The activated macrophages then stimulate an amplified pro-inflammatory cytokine response from the adjacent pleural mesothelial cells. This mechanism for producing a pro-inflammatory environment in the pleural space exposed to long CNT has implications for the general understanding of fibre-related pleural disease and design of safe nanofibres.

Anti-Inflammatory Effects of Adrenomedullin on Acute Lung Injury Induced by Carrageenan in Mice

Adrenomedullin (AM) is a 52 amino acid peptide that has shown predominant anti-inflammatory activities. In the present study, we evaluated the possible therapeutic effect of this peptide in an experimental model of acute inflammation, the carrageenan- (CAR-) induced pleurisy. Pleurisy was induced by injection of CAR into the pleural cavity of mice. AM (200 ng/kg) was administered by intraperitoneal route 1 h after CAR, and the animals were sacrificed 4 h after that. AM treatment attenuated the recruitment of leucocytes in the lung tissue and the generation and/or the expression of the proinflammatory cytokines as well as the expression of the intercellular cell adhesion molecules. Moreover, AM inhibited the induction of inducible nitric oxide synthase (iNOS), thereby abating the generation of nitric oxide (NO) and prevented the oxidative and nitroxidative lung tissue injury, as shown by the reduction of nitrotyrosine, malondialdehyde (MDA), and poly (ADP-ribose) polymerase (PARP) levels. Finally, we demonstrated that these anti-inflammatory effects of AM were associated with the inhibition of nuclear factor-κB (NF-κB) activation. All these parameters were markedly increased by intrapleural CAR in the absence of any treatment. We report that treatment with AM significantly reduces the development of acute lung injury by downregulating a broad spectrum of inflammatory factors.

PPAR-Gamma Agonist Rosiglitazone Attenuates the Inflammation Caused by Carrageenan in the Mouse Model of Pleurisy

The aim of this study was to investigate the anti-inflammatory efficacy of rosiglitazone (ROSI) in a pleurisy model of carrageenan-induced inflammation. Efficacy was monitored in the mouse pleural cavity by evaluating leukocyte migration, exudate concentration, and myeloperoxidase (MPO) and adenosine deaminase (ADA) activities concomitantly with nitrate/nitrite (NOx), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-17A (IL-17A), and vascular endothelial growth factor-alpha (VEGF-α) levels 4 and 48 h after pleurisy induction. In both phases (4 and 48 h) of pleurisy, ROSI inhibited all the inflammation parameters that were tested (p<0.05). These results provide evidence that ROSI was efficacious in inhibiting pro-inflammatory mediators. These anti-inflammatory effects are assumed to mainly result from the inhibition of products released from activated leukocytes, such as MPO, ADA, NOx, TNF-α, IL-1β, IL-17A, and VEGF-α.

Blockade of Proteinase-Activated Receptor-4 Inhibits the Eosinophil Recruitment Induced by Eotaxin-1 in the Pleural Cavity of Mice

Objective and Design: Although proteinase-activated receptor (PAR)-4 has been implicated in inflammation, its role in regulating eosinophil recruitment in response to chemoattractants has not yet been demonstrated. To investigate the contribution of proteinases and PAR-4 activation to eosinophil migration in response to eotaxin-1 or leukotriene B₄ (LTB₄), the effects of aprotinin or PAR-4 antagonist trans-cinnamoyl-YPGKF-NH₂ (tcY-NH₂) on eosinophil migration induced by these chemoattractants were investigated. Methods: BALB/c mice were pretreated with aprotinin or tcY-NH₂ (30 µg/mouse) prior to intrapleural injection of LTB₄ or eotaxin-1 and the number of infiltrating eosinophils was determined 48 h later. Results: Aprotinin (1 mg/kg) inhibited eosinophil recruitment induced by eotaxin-1 (p < 0.01), but not that induced by LTB₄. Moreover, tcY-NH₂ treatment inhibited eosinophil recruitment in response to eotaxin-1 (p < 0.01 by ANOVA/Tukey post-test). Conclusion: These data suggest that aprotinin-inhibited proteinases participate in eosinophil migration induced by eotaxin-1 and that PAR-4 activation plays an important role in regulating this migration.

Leukotriene B4 mediates γδ T lymphocyte migration in response to diverse stimuli

Herein, we investigated the involvement of the 5-LO-derived lipid mediator LTB(4) in gammadelta T cell migration. When injected into the i.pl. space of C57BL/6 mice, LTB(4) triggered gammadelta T lymphocyte mobilization in vivo, a phenomenon also observed in in vitro chemotaxis assays. The i.pl. injection of Escherichia coli endotoxin (LPS) triggered increased levels of LTB(4) in pleural cavities. The in vivo inhibition of LTB(4) biosynthesis by the 5-LO inhibitor zileuton or the FLAP inhibitor MK886 attenuated LPS-induced gammadelta T cell accumulation into pleural cavities. Accordingly, 5-LO KO mice failed to recruit gammadelta T cells into the inflammatory site after i.pl. LPS. Antagonists of the high-affinity LTB(4) receptor BLT1, CP105,696, and LY292476 also attenuated LPS-induced gammadelta T cell accumulation in pleural cavities as well as in vitro chemotaxis toward pleural washes obtained from LPS-simulated mice. LTB(4)/BLT1 also accounted for gammadelta T cell migration induced by i.pl. administration of Mycobacterium bovis BCG or antigen in sensitized mice. BLT1 was expressed on naïve, resident as well as LPS-recruited gammadelta T cells. Isolated gammadelta T cells were found to undergo F-actin cytoskeleton reorganization when incubated with LTB(4) in vitro, confirming that gammadelta T lymphocytes can respond directly to LTB(4). In addition to its direct effect on gammadelta T cells, LTB(4) triggered their accumulation indirectly, via modulation of CCL2 production in mouse pleural cavities. These data show that gammadelta T cell migration into the pleural cavity of mice during diverse inflammatory responses is dependent on LTB(4)/BLT1.

Antioxidant effects of mycophenolate mofetil in a murine pleurisy model

Generation of oxidative stress induced by reactive oxygen species (ROS) and nitrogen (RNS) is believed to be a primary factor in the etiology of various inflammatory diseases. Although, the process of generation of oxygen species is a physiological event, in the inflammatory process this event is increased and produces large amounts of reactive species that leads to lipid peroxidation and to cell death. Mycophenolate mofetil (MMF) is a drug effective in protecting against chronic allograft failure and recently was introduced as an alternative for the treatment of various inflammatory diseases such as glomerulopathies, systemic lupus erythematosus and systemic vasculitis. Based on studies of the anti-inflammatory effect of MMF the aim of this study was to evaluate the effects of MMF on the inhibition of leukocytes and exudation, as well as myeloperoxidase and some antioxidant enzyme activities using carrageenan-induced pleurisy in mice. Our results showed that MMF significantly decreased leukocyte influx ( P < 0.01), exudation ( P < 0.01), superoxide dismutase ( P < 0.05), catalase ( P < 0.05), glutathione peroxidase ( P < 0.01), glutathione S-transferase ( P < 0.01) activities, levels of lipid peroxidation ( P < 0.05), as well as myeloperoxidase activity ( P < 0.05) on both phases (4 h and 48 h) of the inflammatory response induced by carrageenan into the mice pleural cavity. In conclusion, the anti-inflammatory effect of MMF may be, at least in part, via inhibition of ROS and/or NRS overgeneration, and consequently, attenuating the related oxidative stress.

Involvement of CC chemokines in T lymphocyte trafficking during allergic inflammation: the role of CCL2/CCR2 pathway

In the present study, we show that the intra-thoracic injection of ovalbumin (OVA, 12.5 microg per cavity) into C57BL/10 mice induced a significant increase in gammadelta T lymphocyte numbers in the pleural cavity, blood and thoracic lymph node of challenged mice. Such increase was significant within 12 h, peaked within 48 h and returned to basal counts within 120 h. Levels of CC chemokine ligand (CCL)-2/monocyte chemotactic protein-1, CCL5/regulated upon activation, normal T cell expressed and secreted, CCL3/macrophage inflammatory protein-1 alpha and CCL25/thymus-expressed chemokine were above control values in pleural washes recovered 24 h after OVA challenge (OPW) and were likely produced by pleural macrophages and mesothelial cells. Antigenic challenge also induced an up-regulation in CC chemokine receptor (CCR)-2, CCR5 and CCR9 on gammadelta T cells from pleural cavities, blood and lymph nodes, suggesting that cells found in mice pleural cavity migrate from secondary lymphoid organs into the inflammatory site via blood stream. The in vitro neutralization of CCL2 (but not of CCL3, CCL5 or CCL25) abrogated OPW-induced gammadelta T lymphocyte transmigration. Confirming such results, the in vivo administration of alpha-CCL2 mAb inhibited gammadelta T lymphocyte accumulation in the pleural cavity of challenged mice, whereas the blockade of CCL3, CCL5 or CCL25 showed no effect on gammadelta T cell mobilization. In addition, OVA challenge failed to induce gammadelta T lymphocyte accumulation in the pleural cavity of C57BL/6 CCR2 knockout mice, which also showed decreased numbers of these cells in blood and lymph nodes when compared with wild-type mice. Overall, such results demonstrate that CCR2/CCL2 pathway is crucial for gammadelta T lymphocyte mobilization during the allergic response.

Analgesic and anti-inflammatory activity of the aqueous extract of Rheedia longifolia Planch &amp; Triana

Rheedia longifolia Planch et Triana belongs to the Clusiaceae family. This plant is widely distributed in Brazil, but its chemical and pharmacological properties have not yet been studied. We report here that leaves aqueous extract of R. longifolia (LAE) shows analgesic and anti-inflammatory effects. Oral or intraperitoneal administration of this extract dose-dependently inhibited the abdominal constrictions induced by acetic acid in mice. The analgesic effect and the duration of action were similar to those observed with sodium diclofenac, a classical non-steroidal analgesic. In addition to the effect seen in the abdominal constriction model, LAE was also able to inhibit the hyperalgesia induced by lipopolysaccharide from gram-negative bacteria (LPS) in rats. We also found that R. longifolia LAE inhibited an inflammatory reaction induced by LPS in the pleural cavity of mice. Acute toxicity was evaluated in mice treated with the extract for seven days with 50 mg/kg/day. Neither death, nor alterations in weight, blood leukocyte counts or hematocrit were noted. Our results suggest that aqueous extract from R. longifolia leaves has analgesic and anti-inflammatory activity with minimal toxicity and are therefore endowed with a potential for pharmacological control of pain and inflammation.

Antiinflammatory effects of natural tetranortriterpenoids isolated from Carapa guianensis Aublet on zymosan-induced arthritis in mice

We investigated the antiinflammatory properties of a derived fraction of tetranortriterpenoids (TNTP) obtained from the seeds of Carapa guianensis Aublet. Zymosan-induced arthritis and pleurisy in Swiss and C57/Bl6 mice (n = 10 per group). Western blot analysis was performed to analyze nuclear factor-kappaB (NFkappaB) translocation in mice peritoneal macrophages stimulated in vitro with zymosan (500 microg/ml). ELISA was performed to evaluate cytokine levels in knee joints. Values of p </= 0.05 were regarded as significant. Zymosan intra-articular (i. a.) injection (500microg/ cavity) induced a significant increase in knee joint diameter within 6 h, peaked within 24 h and remained above control values for 20 days. Orally-given (p. o.) TNTP (100-200 mg/ kg) inhibited zymosan-induced increase in knee joint diameter and protein extravazation into synovial cavity within 6 h. TNTP (100-200 mg/kg, p. o.) also inhibited total leukocyte influx into the synovial space and tissue, as well as into the mice pleural cavity, due to neutrophil impairment 6 h after zymosan stimulation. The increase in TNF-alpha, IL-1beta and CXCL8/IL-8 levels that were detected in knee synovial extracts obtained from zymosan-stimulated mice was also inhibited by TNTP (100 mg/kg, p. o.). Moreover, the incubation of mice peritoneal macrophages with TNTP (100 mug/ml) inhibited zymosan (500 microg/ml)-induced NFkappaB translocation into the nucleus 6 h after stimulation. Taken together, these results indicate that TNTP present an important antiinflammatory effect, inhibiting zymosan-induced arthritis in mice via the impairment of TNF-alpha, IL-1beta and CXCL8/IL-8 generation, as well as NFkappaB signaling pathway.

Investigations on the anti-inflammatory and anti-allergic activities of the leaves of Uncaria guianensis (Aublet) J. F. Gmelin

Uncaria guianensis (Aublet) J. F. Gmelin is an herbal medicine from tropical areas of South and Central America. We investigated the anti-inflammatory and anti-allergic properties of an ethanolic extract of U. guianensis leaves, containing alkaloids, flavonoids and phenol carboxylic acids, as revealed by thin layer chromatography (TLC). Oral pre-treatment with U. guianensis inhibited zymosan-induced paw oedema (500 mg/paw) and pleural exudation (100 mg/kg) within 4 h (25-200 mg/kg). U. guianensis (100 mg/kg) inhibited total leukocyte and neutrophil numbers in the pleural cavity 4 h after zymosan stimulation. Pre-treatment with U. guianensis (100 mg/kg, p.o.) inhibited total leukocyte, neutrophil and eosinophil recruitment into the pleural cavity 24 h after LPS (250 ng/cavity, i.t.). Pre-treatment with U. guianensis inhibited paw oedema (25-200 mg/kg) induced by ovalbumin (OVA) within 1 h, and neutrophil and eosinophil recruitment into the mice pleural cavity 24 h after OVA (100 mg/kg). In vitro data revealed that U. guianensis impaired LPS-induced nitric oxide and CXCL8 generation by murine peritoneal macrophages, as well as OVA-induced interleukin-5 synthesis by previously sensitized spleen cells. These results demonstrate that U. guianensis leaves provide effective anti-inflammatory and anti-allergic activities.

Frutalin, a galactose-binding lectin, induces chemotaxis and rearrangement of actin cytoskeleton in human neutrophils: Involvement of tyrosine kinase and phosphoinositide 3-kinase

Several lectin-like molecules have been shown as potent activators of leukocytes. Galactose-binding lectins are of special interest since they could interact with several endogenous molecules involved in the innate and specific immune responses. The effects of Frutalin (FTL), an α- d-galactose (Gal)-binding plant lectin, on the modulation of neutrophil (PMN) functions were investigated. FTL induced a dose-dependent PMN migration in mice pleural cavity. Moreover, FTL was also a potent direct chemotactic for human PMN, in vitro, and triggered oxidative burst in these cells. These effects were accompanied by a rearrangement of the actin cytoskeleton dynamic, activation of tyrosine kinase (TK) pathways, increase in focal adhesion kinase (FAK) phosphorylation, and its subsequent association to phosphoinositide3-kinase (PI3K). All those effects were inhibited in the presence of Gal, suggesting specific carbohydrate recognition for FTL effects. The activations of TK and PI3K pathways are essential events for FTL-induced chemotaxis, since inhibitors of these pathways, genistein and LY294002, inhibited neutrophil migration in vitro. The data indicate that sugar–protein interactions between a soluble lectin and galacto-components on neutrophil surface trigger the TK pathway, inducing FAK and PI3K activation, interfering with cell motility and oxidative response.

Anti-inflammatory Activity in the Aqueous Crude Extract of the Leaves of Nidularium procerum: A Bromeliaceae from the Brazilian Coastal Rain Forest

Nidularium procerum LINDMAN, a common bromeliaceae from the Brazilian flora, remains poorly studied regarding its chemical and pharmacological properties. We have recently published that N. procerum has potent analgesic and anti-inflammatory activities. In the present work, we have investigated potential mechanisms involved in the anti-inflammatory effects of N. procerum aqueous extract on lipopolysaccharide (LPS)-, platelet activating factor (PAF)- or formyl-methionyl-leucyl-phenylalanine (fMLP)-induced pleurisy models of inflammation. We found that the aqueous extract of N. procerum leaves (leaf aqueous extract; LAE) inhibits the neutrophil migration, production of inflammatory cytokines interleukin-1 and -6 (IL-1 and IL-6) and the generation of prostaglandin E2 (PGE2) in LPS-induced pleural inflammation in mice. Such inhibitory effect of N. procerum on PGE2 generation was tightly correlated to the inhibition of formation of new cytoplasmic lipid bodies within recruited leukocytes. N. procerum also blocked the in vivo neutrophil influx induced by injection of PAF or fMLP into the mouse pleural cavity and directly inhibited PAF-induced neutrophil chemotaxis in vitro. The data obtained in this study indicate that N. procerum LAE exerts its anti-inflammatory effects by interfering with the capacity of the host to respond to injury at different levels. Among the different functions affected by N. procerum LAE, lipid body formation, PGE2 and cytokine production and neutrophil chemotaxis are readily evidenced in relevant surrogate models. The N. procerum bioactive profile makes it an attractive candidate for future development as a drug or phytomedicine.