cis-Aconitic Acid, a Constituent of Echinodorus grandiflorus Leaves, Inhibits Antigen-Induced Arthritis and Gout in Mice.

cis-Aconitic acid is a constituent from the leaves of Echinodorus grandiflorus, a medicinal plant traditionally used in Brazil to treat inflammatory conditions, including arthritic diseases. The present study aimed to investigate the anti-arthritic effect of cis-aconitic acid in murine models of antigen-induced arthritis and monosodium urate-induced gout. The possible underlying mechanisms of action was evaluated in THP-1 macrophages. Oral treatment with cis-aconitic acid (10, 30, and 90 mg/kg) reduced leukocyte accumulation in the joint cavity and C-X-C motif chemokine ligand 1 and IL-1ß levels in periarticular tissue. cis-Aconitic acid treatment reduced joint inflammation in tissue sections of antigen-induced arthritis mice and these effects were associated with decreased mechanical hypernociception. Administration of cis-aconitic acid (30 mg/kg p. o.) also reduced leukocyte accumulation in the joint cavity after the injection of monosodium urate crystals. cis-Aconitic acid reduced in vitro the release of TNF-α and phosphorylation of IκBα in lipopolysaccharide-stimulated THP-1 macrophages, suggesting that inhibition of nuclear factor kappa B activation was an underlying mechanism of cis-aconitic acid-induced anti-inflammatory effects. In conclusion, cis-aconitic acid has significant anti-inflammatory effects in antigen-induced arthritis and monosodium urate-induced arthritis in mice, suggesting its potential for the treatment of inflammatory diseases of the joint in humans. Additionally, our findings suggest that this compound may contribute to the anti-inflammatory effect previously reported for E. grandiflorus extracts.

Uncoupling of invasive bacterial mucosal immunogenicity from pathogenicity.

There is the notion that infection with a virulent intestinal pathogen induces generally stronger mucosal adaptive immunity than the exposure to an avirulent strain. Whether the associated mucosal inflammation is important or redundant for effective induction of immunity is, however, still unclear. Here we use a model of auxotrophic Salmonella infection in germ-free mice to show that live bacterial virulence factor-driven immunogenicity can be uncoupled from inflammatory pathogenicity. Although live auxotrophic Salmonella no longer causes inflammation, its mucosal virulence factors remain the main drivers of protective mucosal immunity; virulence factor-deficient, like killed, bacteria show reduced efficacy. Assessing the involvement of innate pathogen sensing mechanisms, we show MYD88/TRIF, Caspase-1/Caspase-11 inflammasome, and NOD1/NOD2 nodosome signaling to be individually redundant. In colonized animals we show that microbiota metabolite cross-feeding may recover intestinal luminal colonization but not pathogenicity. Consequent immunoglobulin A immunity and microbial niche competition synergistically protect against Salmonella wild-type infection.

Phosphoinositide-3 kinase gamma regulates caspase-1 activation and leukocyte recruitment in acute murine gout.

This study investigates the participation of PI3Kγ in the development of joint inflammation and dysfunction in an experimental model of acute gout in mice. Acute gout was induced by injection of monosodium urate (MSU) crystals into the tibiofemoral joint of mice. The involvement of PI3Kγ was evaluated using a selective inhibitor and mice deficient for PI3Kγ (PI3Kγ-/- ) or with loss of kinase activity. Neutrophils recovered from the inflamed joint were quantified and stained for phosphorylated Akt (pAkt) and production of reactive oxygen species (ROS). The adherence of leukocytes to the joint microvasculature was assessed by intravital microscopy and cleaved caspase-1 by Western blot. Injection of MSU crystals induced massive accumulation of neutrophils expressing phosphorylated Akt. In the absence of PI3Kγ, there was reduction of pAkt expression, chemokine production, and neutrophil recruitment. Genetic or pharmacological inhibition of PI3Kγ reduced the adherence of leukocytes to the joint microvasculature, even in joints with established inflammation. Neutrophils from PI3Kγ-/- mice produced less ROS than wild-type neutrophils. There was decreased joint damage and dysfunction in the absence of PI3Kγ. In addition, in the absence of PI3Kγ activity, there was reduction of cleaved caspase-1 and IL-1ß production in synovial tissue after injection of MSU crystals and leukotriene B4 . Our studies suggest that PI3Kγ is crucial for MSU crystal-induced acute joint inflammation. It is necessary for regulating caspase-1 activation and for mediating neutrophil migration and activation. Drugs that impair PI3Kγ function may be useful to control acute gout inflammation.

D-Alanine-Controlled Transient Intestinal Mono-Colonization with Non-Laboratory-Adapted Commensal E. coli Strain HS.

Soon after birth the mammalian gut microbiota forms a permanent and collectively highly resilient consortium. There is currently no robust method for re-deriving an already microbially colonized individual again-germ-free. We previously developed the in vivo growth-incompetent E. coli K-12 strain HA107 that is auxotrophic for the peptidoglycan components D-alanine (D-Ala) and meso-diaminopimelic acid (Dap) and can be used to transiently associate germ-free animals with live bacteria, without permanent loss of germ-free status. Here we describe the translation of this experimental model from the laboratory-adapted E. coli K-12 prototype to the better gut-adapted commensal strain E. coli HS. In this genetic background it was necessary to complete the D-Ala auxotrophy phenotype by additional knockout of the hypothetical third alanine racemase metC. Cells of the resulting fully auxotrophic strain assembled a peptidoglycan cell wall of normal composition, as long as provided with D-Ala and Dap in the medium, but could not proliferate a single time after D-Ala/Dap removal. Yet, unsupplemented bacteria remained active and were able to complete their cell cycle with fully sustained motility until immediately before autolytic death. Also in vivo, the transiently colonizing bacteria retained their ability to stimulate a live-bacteria-specific intestinal Immunoglobulin (Ig)A response. Full D-Ala auxotrophy enabled rapid recovery to again-germ-free status. E. coli HS has emerged from human studies and genomic analyses as a paradigm of benign intestinal commensal E. coli strains. Its reversibly colonizing derivative may provide a versatile research tool for mucosal bacterial conditioning or compound delivery without permanent colonization.

Effect of the Hydroethanolic Extract from Echinodorus grandiflorus Leaves and a Fraction Enriched in Flavone-C-Glycosides on Antigen-Induced Arthritis in Mice.

The leaves of Echinodorus grandiflorus are traditionally used in Brazil to treat several inflammatory conditions, including arthritis. This study aimed to investigate the antiarthritis activity of the 70% ethanol extract of E. grandiflorus leaves and a standardized flavonoid-rich fraction in an antigen-induced arthritis model in mice. Previously immunized mice were treated per os with saline (control group), 70% ethanol extract (100-1000 mg/kg), or a flavonoid-rich fraction (0.7-7.2 mg/kg) 40 minutes before and 3 and 6 hours after the challenge with antigen into the knee joint. The administration of the 70% ethanol extract and flavonoid-rich fraction to mice significantly reduced neutrophil recruitment to the joint cavity and in periarticular tissue. The levels of chemokine (C-X-C motif) ligand 1, tumor necrosis factor-α, and interleukin-1ß quantified by the enzyme-linked immunosorbent assay (ELISA) in the periarticular tissue were also diminished in mice treated with the 70% ethanol extract and flavonoid-rich fraction, as well as mechanical hypernociception. Histological analysis confirmed that both the 70% ethanol extract and flavonoid-rich fraction suppressed joint inflammation and inhibited cartilage and bone destruction when compared to the control group. Our results demonstrate, for the first time, that E. grandiflorus has anti-inflammatory activity in an experimental arthritis model and highlights the role of flavonoids in the observed response.

Lithothamnion muelleri treatment ameliorates inflammatory and hypernociceptive responses in antigen-induced arthritis in mice.

Rheumatoid Arthritis (RA) is a chronic disease characterized by persistent inflammation and pain. Alternative therapies to reduce these symptoms are needed. Marine algae are valuable sources of diverse bioactive compounds. Lithothamnion muelleri (Hapalidiaceae) is a marine algae with anti-inflammatory, antitumor, and immunomodulatory properties. Here, we investigated the potential anti-inflammatory and analgesic activities of L. muelleri in a murine model of antigen-induced arthritis (AIA) in mice. Our results demonstrate that treatment with L. muelleri prevented inflammation and hypernociception in arthritic mice. Mechanistically, the crude extract and the polysaccharide-rich fractions of L. muelleri may act impairing the production of the chemokines CXCL1 and CXCL2, and consequently inhibit neutrophil influx to the knee joint by dampening the adhesion step of leukocyte recruitment in the knee microvessels. Altogether our results suggest that treatment with L.muelleri has a potential therapeutic application in arthritis treatment.

Mechanisms of the anti-inflammatory actions of the angiotensin type 1 receptor antagonist losartan in experimental models of arthritis.

Angiotensin (Ang) II and its AT1 receptors have been implicated in the pathogenesis of rheumatoid arthritis. Activation of the counter-regulatory Ang-(1-7)-Mas receptor axis may contribute to some of the effects of AT1 receptor blockers (ARBs). In this study, we have used losartan, an ARB, to investigate the role of and the mechanisms by which AT1 receptors participated in two experimental models of arthritis: antigen-induced arthritis (AIA) in mice and adjuvant-induced arthritis (AdIA) in rats. Treatment with losartan decreased neutrophil recruitment, hypernociception and the production of TNF-α, IL-1ß and chemokine (C-X-C motif) ligand 1 in mice subjected to AIA. Histopathological analysis showed significant reduction of tissue injury and inflammation and decreased proteoglycan loss. In addition to decreasing cytokine production, losartan directly reduced leukocyte rolling and adhesion. Anti-inflammatory effects of losartan were not associated to Mas receptor activation and/or Ang-(1-7) production. Anti-inflammatory effects were reproduced in rats subjected to AdIA. This study shows that ARBs have potent anti-inflammatory effects in animal models of arthritis. Mechanistically, reduction of leukocyte accumulation and of joint damage was associated with local inhibition of cytokine production and direct inhibition of leukocyte-endothelium interactions. The anti-inflammatory actions of losartan were accompanied by functional improvement of the joint, as seen by reduced joint hypernociception. These findings support the use of ARBs for the treatment of human arthritis and provide potential mechanisms for the anti-inflammatory actions of these compounds.

Effects of physical exercise on plasma levels of brain-derived neurotrophic factor and depressive symptoms in elderly women--a randomized clinical trial.

OBJECTIVES: To investigate the effect of 2 standardized exercise programs, muscle strength exercises (SE) and aerobic exercises (AE), on the plasma levels of brain-derived neurotrophic factor (BDNF) and depressive symptoms in 451 elderly women. DESIGN: A randomized controlled trial. SETTING: Belo Horizonte/MG-Brazil. PARTICIPANTS: Community-dwelling older women (N=451; age, 65-89y). INTERVENTION: The participants were divided into 2 groups: SE and AE. Both protocols lasted 10 weeks, and 30 sessions (1-h sessions) in total were performed 3 times a week under the direct supervision of physical therapists. MAIN OUTCOME MEASURES: Plasma levels of BDNF (enzyme-linked immunosorbent assay) and depressive symptoms (Geriatric Depression Scale). RESULTS: There was a significant difference for BDNF plasma levels between the SE and AE groups (P=.009). Post hoc analysis revealed a pre-post intervention difference in BDNF levels only for the SE group (P=.008). A statistically significant difference was found for the pre- and postintervention Geriatric Depression Scale scores in both groups (P=.001), showing that the effects of both exercise protocols were comparable regarding depressive symptoms (P=.185). CONCLUSIONS: The present findings have demonstrated the positive effect of muscle strengthening and aerobic intervention on depressive symptoms in community-dwelling elderly women. Interestingly, only SE significantly increased the plasma levels of BDNF in our sample. The positive effects of physical exercise on depressive symptoms in the elderly were not mediated by BDNF.

Naive B-cell trafficking is shaped by local chemokine availability and LFA-1-independent stromal interactions.

It is not known how naive B cells compute divergent chemoattractant signals of the T-cell area and B-cell follicles during in vivo migration. Here, we used two-photon microscopy of peripheral lymph nodes (PLNs) to analyze the prototype G-protein-coupled receptors (GPCRs) CXCR4, CXCR5, and CCR7 during B-cell migration, as well as the integrin LFA-1 for stromal guidance. CXCR4 and CCR7 did not influence parenchymal B-cell motility and distribution, despite their role during B-cell arrest in venules. In contrast, CXCR5 played a nonredundant role in B-cell motility in follicles and in the T-cell area. B-cell migration in the T-cell area followed a random guided walk model, arguing against directed migration in vivo. LFA-1, but not α4 integrins, contributed to B-cell motility in PLNs. However, stromal network guidance was LFA-1 independent, uncoupling integrin-dependent migration from stromal attachment. Finally, we observed that despite a 20-fold reduction of chemokine expression in virus-challenged PLNs, CXCR5 remained essential for B-cell screening of antigen-presenting cells. Our data provide an overview of the contribution of prototype GPCRs and integrins during naive B-cell migration and shed light on the local chemokine availability that these cells compute.

NLRP3 inflammasome-mediated neutrophil recruitment and hypernociception depend on leukotriene B(4) in a murine model of gout.

OBJECTIVE: Deposition of monosodium urate monohydrate (MSU) crystals in the joints promotes an intense inflammatory response and joint dysfunction. This study evaluated the role of the NLRP3 inflammasome and 5-lipoxygenase (5-LOX)-derived leukotriene B(4) (LTB(4) ) in driving tissue inflammation and hypernociception in a murine model of gout. METHODS: Gout was induced by injecting MSU crystals into the joints of mice. Wild-type mice and mice deficient in NLRP3, ASC, caspase 1, interleukin-1ß (IL-1ß), IL-1 receptor type I (IL-1RI), IL-18R, myeloid differentiation factor 88 (MyD88), or 5-LOX were used. Evaluations were performed to assess neutrophil influx, LTB(4) activity, cytokine (IL-1ß, CXCL1) production (by enzyme-linked immunosorbent assay), synovial microvasculature cell adhesion (by intravital microscopy), and hypernociception. Cleaved caspase 1 and production of reactive oxygen species (ROS) were analyzed in macrophages by Western blotting and fluorometric assay, respectively. RESULTS: Injection of MSU crystals into the knee joints of mice induced neutrophil influx and neutrophil-dependent hypernociception. MSU crystal-induced neutrophil influx was CXCR2-dependent and relied on the induction of CXCL1 in an NLRP3/ASC/caspase 1/IL-1ß/MyD88-dependent manner. LTB(4) was produced rapidly after injection of MSU crystals, and this was necessary for caspase 1-dependent IL-1ß production and consequent release of CXCR2-acting chemokines in vivo. In vitro, macrophages produced LTB(4) after MSU crystal injection, and LTB(4) was relevant in the MSU crystal-induced maturation of IL-1ß. Mechanistically, LTB(4) drove MSU crystal-induced production of ROS and ROS-dependent activation of the NLRP3 inflammasome. CONCLUSION: These results reveal the role of the NLRP3 inflammasome in mediating MSU crystal-induced inflammation and dysfunction of the joints, and highlight a previously unrecognized role of LTB(4) in driving NLRP3 inflammasome activation in response to MSU crystals, both in vitro and in vivo.

Impact of resistance exercise program on functional capacity and muscular strength of knee extensor in pre-frail community-dwelling older women: a randomized crossover trial.

BACKGROUND: Frailty syndrome in elderly people is characterized by a reduction of energy reserves and also by a decreased of resistance to stressors, resulting in an increase of vulnerability. OBJECTIVE: The aim of this study was to verify the effect of a muscle-strengthening program with load in pre-frail elder women with regards to the functional capacity, knee extensor muscle strength and their correlation. METHODS: Thrity-two pre-frail community-dwelling women participated in this study. Potential participants with cognitive impairment (MEEM), lower extremities orthopedic surgery, fractures, inability to walk unaided, neurological diseases, acute inflammatory disease, tumor growth, regular physical activity and current use of immunomodulators were excluded. All partcipants were evaluated by a blinded assessor using: Timed up and go (TUG), 10-Meter Walk Test (10MWT) and knee extensor muscle strength (Byodex System 3 Pro® isokinetic dynamometer at angular speeds of 60 and 180(0)/s). The intervention consisted of strengthening exercises of the lower extremities at 70% of 1RM, three times/ week for ten weeks. The statistical analysis was performed using the ANOVA and Spearman tests RESULTS: After the intervention, it was observed statistical significance on the work at 180(0)/s (F=12.71, p=0.02), on the power at 180(0)/s (F=15.40, p=0.02) and on the functional capacity (TUG, F=9.54, p=0.01; TC10, F=3.80, p=0.01). There was a good negative and statistically significant correlation between the TUG and work at 60(0)/s, such as the TUG and work at 180(0)/s (r=-0.65, p=0.01; r=-0.72, p=0.01). CONCLUSION: The intervention improved the muscular power and the functional capacity. The increase of the power correlated with function, which is an important variable of the quality of life in the pre-frail elders. Article registered in the ISRCT register under number ISRCTN62824599.

Efeito de um programa de resistência muscular na capacidade funcional e na força muscular dos extensores do joelho em idosas pré-frágeis da comunidade: ensaio clínico aleatorizado do tipo crossover / Impact of resistance exercise program on functional capacity and muscular strength of knee extensor in pre-frail community-dwelling older women: a randomized crossover trial

CONTEXTUALIZAÇÃO: Na síndrome de fragilidade em idosos, há diminuição das reservas de energia e resistência aos estressores, com aumento da vulnerabilidade. OBJETIVO: Verificar o efeito do treinamento de força muscular com carga na capacidade funcional e força muscular dos extensores do joelho e sua associação, após treinamento, em idosas pré-frágeis da comunidade. MÉTODOS:Participaram 32 idosas, pré-frágeis, da comunidade. Excluíram-se aquelas com Miniexame do Estado Mental (MEEM) incompatível; cirurgias ortopédicas dos membros inferiores; fraturas; doenças neurológicas; doenças inflamatórias agudas; neoplasias; atividade física regular; uso de medicamento com ação no sistema imunológico e sem marcha independente. Avaliou-se a capacidade funcional (Timed Up and Go - TUG e velocidade de marcha - TC10) e a força muscular dos extensores do joelho (Byodex System 3 Pro®) nas velocidades angulares de 60 e 180(0)/s. Para o fortalecimento muscular, utilizou-se carga de 75 por cento de resistência máxima (1RM), durante dez semanas, três vezes/semana. A análise estatística foi feita pela ANOVA e Spearman (α=5 por cento). RESULTADOS: Após o treinamento, houve melhora estatística do trabalho normalizado em 180(0)/s (F=12,71, p=0,02), na potência, em 180(0)/s (F=15,40, p=0,02) e na capacidade funcional (TUG, F=9,54, p=0,01; TC10, F=3,80, p=0,01). Houve boa correlação negativa significativa do TUG com as medidas de trabalho normalizado em 60 e 180(0)/s (r=-0,65, p=0,01; r=-0,72, p=0,01). CONCLUSÃO: O treinamento produziu melhora da potência muscular e capacidade funcional. A melhora da potência associou-se à melhora funcional, importante variável para a qualidade de vida de idosas pré-frágeis. Artigo registrado no ISRCT register sob o número ISRCTN62824599.

BACKGROUND: Frailty syndrome in elderly people is characterized by a reduction of energy reserves and also by a decreased of resistance to stressors, resulting in an increase of vulnerability. OBJECTIVE: The aim of this study was to verify the effect of a muscle-strengthening program with load in pre-frail elder women with regards to the functional capacity, knee extensor muscle strength and their correlation. METHODS: Thrity-two pre-frail community-dwelling women participated in this study. Potential participants with cognitive impairment (MEEM), lower extremities orthopedic surgery, fractures, inability to walk unaided, neurological diseases, acute inflammatory disease, tumor growth, regular physical activity and current use of immunomodulators were excluded. All partcipants were evaluated by a blinded assessor using: Timed up and go (TUG), 10-Meter Walk Test (10MWT) and knee extensor muscle strength (Byodex System 3 Pro® isokinetic dynamometer at angular speeds of 60 and 180(0)/s). The intervention consisted of strengthening exercises of the lower extremities at 70 percent of 1RM, three times/ week for ten weeks. The statistical analysis was performed using the ANOVA and Spearman tests RESULTS: After the intervention, it was observed statistical significance on the work at 180(0)/s (F=12.71, p=0.02), on the power at 180(0)/s (F=15.40, p=0.02) and on the functional capacity (TUG, F=9.54, p=0.01; TC10, F=3.80, p=0.01). There was a good negative and statistically significant correlation between the TUG and work at 60(0)/s, such as the TUG and work at 180(0)/s (r=-0.65, p=0.01; r=-0.72, p=0.01). CONCLUSION: The intervention improved the muscular power and the functional capacity. The increase of the power correlated with function, which is an important variable of the quality of life in the pre-frail elders. Article registered in the ISRCT register under number ISRCTN62824599.

Resolution of neutrophilic inflammation by H2O2 in antigen-induced arthritis.

OBJECTIVE: Neutrophil accumulation contributes to the pathogenesis of rheumatoid arthritis. This study was undertaken to examine the ability of H2O2 to influence neutrophilic inflammation in a model of antigen-induced arthritis (AIA) in mice. METHODS: AIA was induced by administration of antigen into the knee joints of previously immunized mice. Neutrophil accumulation was measured by counting neutrophils in the synovial cavity and assaying myeloperoxidase activity in the tissue surrounding the mouse knee joint. Apoptosis was determined by morphologic and molecular techniques. The role of H2O2 was studied using mice that do not produce reactive oxygen species (gp91phox-/- mice) and drugs that enhance the generation or enhance the degradation of H2O2. RESULTS: Antigen challenge of immunized mice induced neutrophil accumulation that peaked at 12-24 hours after challenge. H2O2 production peaked at 24 hours, after which time, the inflammation resolved. Neutrophil recruitment was similar in wild-type and gp91phox-/- mice, but there was delayed resolution in gp91phox-/- mice or after administration of catalase. In contrast, administration of H2O2 or superoxide dismutase (SOD) resolved neutrophilic inflammation. The resolution of inflammation induced by SOD or H2O2 was accompanied by an increase in the number of apoptotic neutrophils. Apoptosis was associated with an increase in Bax and caspase 3 cleavage and was secondary to phosphatidylinositol 3-kinase (PI3K)/Akt activation. CONCLUSION: Our findings indicate that levels of H2O2 increase during neutrophil influx and are necessary for the natural resolution of neutrophilic inflammation. Mechanistically, enhanced levels of H2O2 (endogenous or exogenous) inhibit p-Akt/NF-κB and induce apoptosis of migrated neutrophils. Modulation of H2O2 production may represent a novel strategy for controlling neutrophilic inflammation in the joints.

Cooperative role of tumour necrosis factor-α, interleukin-1ß and neutrophils in a novel behavioural model that concomitantly demonstrates articular inflammation and hypernociception in mice.

UNLABELLED: BACKGROUND AND PURPOSE; Chronic joint inflammation and pain are the hallmarks of disease in patients with inflammatory arthritis, notably rheumatoid arthritis. The aim of the present study was to investigate the relative contribution of tumour necrosis factor (TNF)-α, interleukin (IL)-1ß and neutrophil influx for joint inflammation and nociception in a novel murine model of antigen-induced arthritis (AIA). EXPERIMENTAL APPROACH: AIA was induced by administration of antigen into knee joint of previously immunized mice. Neutrophil accumulation was determined by counting neutrophils in the joints and assessing myeloperoxidase activity in tissues surrounding the joints. TNF-α, IL-1ß and CXCL-1 were measured by elisa. Mechanical hypernociception was assessed in parallel, using an electronic pressure meter. KEY RESULTS: Hypernociception was dependent on antigen dose and the time after its administration; it was prevented by treatment with morphine and associated with neutrophil infiltration and local production of TNF-α, IL-1ß and CXCL-1. Administration of a chimeric monoclonal antibody to TNF-α (infliximab) or IL-1receptor antagonist prevented neutrophil influx and hypernociception, and this was comparable to the effects of dexamethasone. Treatment with fucoidin (a leucocyte adhesion inhibitor) greatly suppressed neutrophil influx and local production of TNF-α and IL-1ß, and hypernociception. CONCLUSIONS AND IMPLICATIONS: In conclusion, the present study describes a new model that allows for the concomitant evaluation of articular hypernociception and inflammation. Using this system, we demonstrated that a positive feedback loop involving neutrophil influx and the pro-inflammatory cytokines TNF-α and IL-1ß is necessary for articular hypernociception after antigen challenge of immunized mice.

The effects of a muscle resistance program on the functional capacity, knee extensor muscle strength and plasma levels of IL-6 and TNF-alpha in pre-frail elderly women: a randomized crossover clinical trial--a study protocol.

BACKGROUND: With the increase in the elderly population, a growing number of chronic degenerative diseases and a greater dependency on caregivers have been observed. Elderly persons in states of frailty remain more susceptible to significant health complications. There is evidence of an inverse relationship between plasma levels of inflammatory mediators and levels of functionality and muscle strength, suggesting that muscle-strengthening measures can aid in inflammatory conditions. The purpose of this study will be verified the effect of a muscle-strengthening program with load during a ten-week period in pre-frail elderly women with attention to the following outcomes: (1) plasma levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha), (2) functional capacity and (3) knee extensor muscle strength. METHODS/DESIGN: The study design is a randomized crossover clinical trial evaluating 26 elderly women (regardless of their race and/or social condition) who are community residents, older than 65, and classified as pre-frail according to the criteria previously described by Fried et al. (2004). All subjects will be assessed using the Timed up and go and 10-Meter Walk Test functional tests. The plasma levels of IL-6 and TNF-alpha will be assessed by ELISA (enzyme-linked immunosorbent assay) with high sensitivity kits (QuantikineHS, R&D Systems Minneapolis, MN, U.S.). Knee extensor muscle strength will be assessed using the Byodex System 3 Pro(R) isokinetic dynamometer at angular speeds of 60 and 180 degrees/s. The intervention will consist of strengthening exercises of the lower extremities at 50 to 70% of 1RM (maximal resistance) three times per week for ten weeks. The volunteers will be randomized into two groups: group E, the intervention group, and group C, the control group that did not initiate any new activities during the initial study period (ten weeks). After the initial period, group C will begin the intervention and group E will maintain everyday activities without exercising. At the end of the total study period, all volunteers will be reassessed. DISCUSSION: To demonstrate and discuss possible influences of load-bearing exercises on the modification of plasma levels of IL-6 and TNF-alpha and in the functional performance of pre-frail elderly women. TRIAL REGISTRATION: ISRCTN62824599.

Role of IL-13 in a model of Strongyloides venezuelensis infection in rats.

IL-13 is a cytokine known to play a role in several pulmonary diseases, including asthma and fibrosis. The role of IL-13 in the context of pulmonary changes induced by helminth infection is unclear. Rats experimentally infected with Strongyloides venezuelensis and treated with anti-IL-13 neutralizing antibody were used to evaluate the role of IL-13 on functional and inflammatory changes of host lungs, and on parasite control. S. venezuelensis-induced airway hyperreactivity was IL-13-independent, but IL-13 played an essential role in driving airway mucus production and eosinophil infiltration. IL-13 was important for the control of egg production but not establishment in the intestine.

The long pentraxin PTX3 is crucial for tissue inflammation after intestinal ischemia and reperfusion in mice.

The pentraxin superfamily is a group of evolutionarily conserved proteins that play important roles in the immune system. The long pentraxin PTX3 protein was originally described as able to be induced by pro-inflammatory stimuli in a variety of cell types. In this study, we evaluated the phenotype of Ptx3(-/-) mice subjected to ischemia followed by reperfusion of the superior mesenteric artery. In reperfused wild-type mice, there was significant local and remote injury as demonstrated by increases in vascular permeability, neutrophil influx, nuclear factor-kappaB activation, and production of CXCL1 and tumor necrosis factor-alpha. PTX3 levels were elevated in both serum and intestine after reperfusion. In Ptx3(-/-) mice, local and remote tissue injury was inhibited, and there were decreased nuclear factor-kappaB translocation and cytokine production. Intestinal architecture was preserved, and there were decreased neutrophil influx and significant prevention of lethality in Ptx3(-/-) mice as well. PTX3 given intravenously before reperfusion reversed the protection observed in Ptx3(-/-) mice in a dose-dependent manner, and PTX3 administration significantly worsened tissue injury and lethality in wild-type mice. In conclusion, our studies demonstrate a major role for PTX3 in determining acute reperfusion-associated inflammation, tissue injury, and lethality and suggest the soluble form of this molecule is active in this system. Therapeutic blockade of PTX3 action may be useful in the control of the injuries associated with severe ischemia and reperfusion syndromes.

All-or-nothing type biphasic cytokine production of human lymphocytes after exposure to Alzheimer's beta-amyloid peptide.

BACKGROUND: Neuro-inflammation, triggered by beta-amyloid peptide, is implicated as one of the primary contributors to Alzheimer's disease (AD) pathogenesis, and several cytokines were identified as key instigating factors. METHODS: To reveal the inflammatory response of lymphocytes to the neuro-toxic beta-amyloid peptide, we evaluated the release of several cytokines from peripheral blood mononuclear cells with immuno-assays (ELISA). From hyper-acute to chronic effects of beta-amyloid peptide were assessed at a wide range of concentrations. RESULTS: The pro-inflammatory interleukin (IL)-1beta, tumor necrosis factor-alpha, monocyte chemotactic protein-1, and Rantes (acronym for regulated on activation, normal T-cell expressed and secreted) as well as the pleiotropic IL-6 showed a biphasic release pattern over time in both low and high doses of amyloid treatment: after an initial increase, their concentration gradually fell to the baseline. The suppressors IL-4 and IL-10 had a sinus-like secretion panel: an acute increase in their levels turned to a depression and later followed by their over-secretion. Interestingly, beta-amyloid below 10(-8) mol/L produced no effect at all, but any molarity above this threshold caused the very same cytokine secretion pattern, the mark of an all-or-nothing response of beta-amyloid peptide. CONCLUSIONS: These results delineate a highly organized pro- and anti-inflammatory response of cells to the neuro-toxic peptide. This is the first study to describe how the beta-amyloid-induced inflammatory processes in Alzheimer's dementia are regulated.

Electrocardiographic parameters of captive lions (Panthera leo) and tigers (Panthera tigris) immobilized with ketamine plus xylazine.

Twenty-seven healthy captive lions (Panthera leo) and 13 healthy captive tigers (Panthera tigris) from São Paulo Zoo (Fundação Parque Zoológico de Sã Paulo, São Paulo, Brazil) collection were selected for this study. They were anesthetized with ketamine (10 mg/kg) combined with xylazine (1-2 mg/kg) for physical examinations, hematologic and serum chemical analysis and electrocardiogram recording. The main aim of this research was to gather initial information about normal electrocardiographic parameters of large felids. Standard P-QRS-T deflections on leads described for domestic carnivores were analyzed, and they did not greatly differ from those of large felids, taking into account the greater weight and corporal mass of large felids. Heart rate of lions ranged from 42 to 76 beats per minute (bpm). Heart rate of tigers ranged from 56 to 97 bpm. In both species, the most common rhythm detected was normal sinus rhythm followed by sinus arrhythmia; wandering pacemaker was also observed with normal sinus rhythm or sinus arrhythmia. Mean electrical axis lay between +60 degrees and +120 degrees. QRS complexes were predominantly positive in leads DI, DII, DIII, and AVF, and negative in AVR and AVL. This study provides insights into normal electrocardiograms of large felids. Wider investigations on the same subject are necessary to establish criteria for the recognition of abnormalities in these species and should include other anesthetic drug(s) combinations and reports of electrocardiographic features of animals with cardiac disease and electrolytes disturbances.