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BACKGROUND: The interest in approaches that improve older individuals' functional fitness and autonomy is increasing. However, the effects of dual-task training on older women's functional fitness and the comparison with the functional training approach are unclear. Therefore, we compared dual-task and functional training on the functional fitness of older women and the effects of three months of detraining. METHODS: Sixty-one women performed 16 weeks of dual-task training or functional training. The functional fitness was measured pre-, post-training, and post-detraining, based on the ability to put on and take off a t-shirt, evaluating the mobility of the upper limb, standing-up from the prone position measuring the global functionality, five times sit-to-stand test to assess the lower limbs muscle power, timed up and go to measure the dynamic balance and agility, gallon-jug shelf-transfer to evaluate the global functionality emphasizing the upper limbs and 10 m walk test to analyze the gait ability. RESULTS: Dual-task training and functional training generally provided significant small to moderate magnitude performance increases in the put on and take off a t-shirt (dual-task training: d = 0.35 / functional training: d = 0.49), five times sit-to-stand test (dual-task training: d = 0.41 / functional training: d = 0.77), timed up and go (dual-task training: d = 0.34 / functional training: d = 0.78), and gallon-jug shelf-transfer (dual-task training: d = 0.76 / functional training: d = 0.82). Only the functional training improved the 10 m walk test (d = 0.32; p = 0.013), and both groups did not change the standing-up from the prone position performance. After the detraining period, both groups kept the adaptations for the gallon-jug shelf-transfer and five times sit-to-stand test. At the same time, only the dual-task training maintained the adaptations for the put on and take off a t-shirt and the functional training for the timed up and go. CONCLUSION: Sixteen weeks of dual-task and functional training are similarly effective in improving older women's functional fitness, maintaining their benefits even after three months of detraining. TRIAL REGISTRATION: RBR-10ny848z ( https://ensaiosclinicos.gov.br/rg/RBR-10ny848z ).
Assuntos
Aptidão Física , Humanos , Feminino , Idoso , Aptidão Física/fisiologia , Equilíbrio Postural/fisiologia , Terapia por Exercício/métodos , Força Muscular/fisiologiaRESUMO
BACKGROUND: Despite visceral leishmaniasis (VL) being epidemic in most Brazilian regions, the Northeast region is responsible for the highest morbidity and mortality outcomes within the country. OBJECTIVE: To analyse the spatiotemporal dynamics of VL cases to identify the temporal trends and high-risk areas for VL transmission, as well as the association of the disease with social vulnerability in Brazilian Northeast. METHODS: We carried out an ecological time series study employing spatial analysis techniques using all VL confirmed cases of 1,794 municipalities of Brazilian Northeast between the years 2000 to 2017. The Social Vulnerability Index (SVI) was used to represent the social vulnerability. Incidence rates were standardized and smoothed by the Local Empirical Bayesian Method. Time trends were examined through segmented linear regression. Spatiotemporal analysis consisted of uni- and bivariate Global and Local Moran indexes and space-time scan statistics. RESULTS: Incidence rate remained stable and ranged from 4.84 to 3.52 cases/100,000 inhabitants. There was higher case prevalence between males (62.71%), children and adolescents (63.27%), non-white (69.75%) and urban residents (62.58%). Increasing trends of new cases were observed among adult male subjects (≥ 40 years old) and urban residents. Importantly, VL incidence showed a direct spatial dependence. Spatial and space-time clusters were identified in sertão and meio-norte sub-regions, overlapping with high social vulnerability areas. CONCLUSIONS: VL is a persistent health issue in Brazilian Northeast and associated with social vulnerability. Space-time clustering of VL cases in socially vulnerable municipalities demands intersectoral public policies of surveillance and control, with focus on reducing inequalities and improving living conditions for regional inhabitants.
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Leishmaniose Visceral/epidemiologia , Fatores Socioeconômicos , Análise Espaço-Temporal , Adolescente , Adulto , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Leishmaniose Visceral/transmissão , Masculino , Pessoa de Meia-Idade , Populações VulneráveisRESUMO
Visceral leishmaniasis (VL) is a systemic transmissible disease that remains to be a major global health problem. The inflammatory response during VL is characterized by the release of several cytokines and other pro-inflammatory mediators. Triggering Receptor Expressed on Myeloid Cells (TREM) are a group of evolutionarily conserved membrane-bound surface receptors expressed on neutrophils and monocytes. Engagement of TREM-1 directs intracellular signaling events that drive cytokine production, degranulation, and phagocytosis. In certain inflammatory-associated diseases, TREM-1 can also be found as a soluble form (sTREM-1), which can negatively regulate TREM-1 receptor signaling. In these studies, we now find that high levels of circulating sTREM-1 correlate directly with VL disease severity. In particular, high levels of sTREM-1 were observed in non-survivor VL patients. Furthermore, these levels of sTREM-1 positively correlated with liver size and negatively correlated with leukocyte counts and hemoglobin concentration. Moreover, we found that neutrophils exposure in vitro to Leishmania infantum modulates TREM-1, DAP12, and IL-8 gene expression, while also increasing release of sTREM-1. Finally, results revealed that higher sTREM-1 levels are associated with increasing parasite ratio. Taken together, these studies suggest that L. infantum may modulate TREM-1 in neutrophils and high levels of this molecule is associated with severe VL.
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BACKGROUND: Visceral leishmaniasis (VL) is a severe disease caused by infection with protozoa of the genus Leishmania. Classic VL is characterized by a systemic infection of phagocytic cells and an intense activation of the inflammatory response. It is unclear why 90% of infected individuals do not develop the disease while a minority develop the classical form. Furthermore, among those that develop disease, a small group progresses to more severe form that is unresponsive to treatment. The presence of inflammatory mediators in serum could theoretically help to control the infection. However, there is also a release of anti-inflammatory mediators that could interfere with the control of parasite multiplication. In this study, we took advantage of the spectrum of outcomes to test the hypothesis that the immune profile of individuals infected with Leishmania (L.) infantum is associated with the development and severity of disease. METHODOLOGY/PRINCIPAL FINDINGS: Sera from patients with confirmed diagnosis of VL were evaluated for the presence of numerous molecules, and levels compared with healthy control and asymptomatic infected individuals. CONCLUSIONS/PRINCIPAL FINDINGS: Although differences were not observed in LPS levels, higher levels of sCD14 were detected in VL patients. Our data suggest that L. infantum may activate the inflammatory response via CD14, stimulating a generalized inflammatory response with production of several cytokines and soluble molecules, including IFN-γ, IL-27, IL-10, IL-6 and sCD14. These molecules were strongly associated with hepatosplenomegaly, neutropenia and thrombocytopenia. We also observed that IL-6 levels greater than 200 pg/ml were strongly associated with death. Together our data reinforce the close relationship of IFN-γ, IL-10, IL-6, TNF-α and IL-27 in the immune dynamics of VL and suggest the direct participation of sCD14 in the activation of the immune response against L. infantum.
Assuntos
Interleucina-27/sangue , Interleucina-6/sangue , Leishmaniose Visceral/sangue , Receptores de Lipopolissacarídeos/sangue , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Leishmania infantum/fisiologia , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/patologia , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Leishmania parasites are transmitted in the presence of sand fly saliva. Together with the parasite, the sand fly injects salivary components that change the environment at the feeding site. Mice immunized with Phlebotomus papatasi salivary gland (SG) homogenate are protected against Leishmania major infection, while immunity to Lutzomyia intermedia SG homogenate exacerbated experimental Leishmania braziliensis infection. In humans, antibodies to Lu. intermedia saliva are associated with risk of acquiring L. braziliensis infection. Despite these important findings, there is no information regarding the repertoire of Lu. intermedia salivary proteins. METHODS AND FINDINGS: A cDNA library from the Salivary Glands (SGs) of wild-caught Lu. intermedia was constructed, sequenced, and complemented by a proteomic approach based on 1D SDS PAGE and mass/mass spectrometry to validate the transcripts present in this cDNA library. We identified the most abundant transcripts and proteins reported in other sand fly species as well as novel proteins such as neurotoxin-like proteins, peptides with ML domain, and three small peptides found so far only in this sand fly species. DNA plasmids coding for ten selected transcripts were constructed and used to immunize BALB/c mice to study their immunogenicity. Plasmid Linb-11--coding for a 4.5-kDa protein--induced a cellular immune response and conferred protection against L. braziliensis infection. This protection correlated with a decreased parasite load and an increased frequency of IFN-γ-producing cells. CONCLUSIONS: We identified the most abundant and novel proteins present in the SGs of Lu. intermedia, a vector of cutaneous leishmaniasis in the Americas. We also show for the first time that immunity to a single salivary protein from Lu. intermedia can protect against cutaneous leishmaniasis caused by L. braziliensis.
Assuntos
Perfilação da Expressão Gênica , Proteínas de Insetos/biossíntese , Leishmania braziliensis/imunologia , Psychodidae/genética , América , Animais , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Feminino , Biblioteca Gênica , Humanos , Imunidade Celular , Proteínas de Insetos/genética , Proteínas de Insetos/imunologia , Proteínas de Insetos/isolamento & purificação , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/prevenção & controle , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Proteoma/análise , Psychodidae/imunologia , Psychodidae/parasitologia , Proteínas e Peptídeos Salivares/biossíntese , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/imunologia , Proteínas e Peptídeos Salivares/isolamento & purificaçãoRESUMO
We recently demonstrated that immunization with polyester poly(lactide-co-glycolide acid) (PLGA) nanoparticles loaded with the 11-kDa Leishmania vaccine candidate kinetoplastid membrane protein 11 (KMP-11) significantly reduced parasite load in vivo. Presently, we explored the ability of the recombinant PLGA nanoparticles to stimulate innate responses in macrophages and the outcome of infection with Leishmania braziliensis in vitro. Incubation of macrophages with KMP-11-loaded PLGA nanoparticles significantly decreased parasite load. In parallel, we observed the augmented production of nitric oxide, superoxide, TNF-α and IL-6. An increased release of CCL2/MCP-1 and CXCL1/KC was also observed, resulting in macrophage and neutrophil recruitment in vitro. Lastly, the incubation of macrophages with KMP-11-loaded PLGA nanoparticles triggered the activation of caspase-1 and the secretion of IL-1ß and IL-18, suggesting inflammasome participation. Inhibition of caspase-1 significantly increased the parasite load. We conclude that KMP-11-loaded PLGA nanoparticles promote the killing of intracellular Leishmania parasites through the induction of potent innate responses. FROM THE CLINICAL EDITOR: In this novel study, KMP-11-loaded PLGA nanoparticles are demonstrated to promote the killing of intracellular Leishmania parasites through enhanced innate immune responses by multiple mechanisms. Future clinical applications would have a major effect on our efforts to address parasitic infections.
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Imunidade Inata/imunologia , Ácido Láctico/química , Leishmania/citologia , Leishmania/imunologia , Nanopartículas/química , Ácido Poliglicólico/química , Proteínas de Protozoários/imunologia , Animais , Morte Celular/efeitos dos fármacos , Quimiocinas/metabolismo , DNA/metabolismo , Feminino , Imunidade Inata/efeitos dos fármacos , Inflamassomos/metabolismo , Ácido Láctico/farmacologia , Leishmania/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/parasitologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/biossíntese , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Superóxidos/metabolismoRESUMO
Leishmania spp. cause a broad spectrum of diseases collectively known as leishmaniasis. Leishmania braziliensis is the main etiological agent of American cutaneous leishmaniasis and mucocutaneous leishmaniasis. During experimental infection with L. braziliensis, BALB/c mice develop an adaptive immune response that is associated with lesion healing and, in parallel, parasite persistence within draining lymph nodes (dLNs). In the Leishmania major model of cutaneous leishmaniasis, regulatory T cells (Tregs) play an important role in immune regulation, preventing pathological immune responses but at the same time precluding sterile cure. In this study we investigated the role of Tregs during experimental infection with L. braziliensis. CD4(+)CD25(+) T cells were detected throughout the duration of clinical disease both at the ear and in dLNs of infected mice. These cells expressed Treg markers such as glucocorticoid-induced TNF-receptor-related protein (GITR), the α chain of the αεß7 integrin (CD103), and the forkhead/winged helix transcription factor, Foxp3, and were able to suppress the proliferation of CD4(+)CD25(-) cells. Importantly, a high frequency of Foxp3(+) cells accumulated at the site of infection and in dLNs. We next investigated the outcome of a reinfection with L. braziliensis in terms of Treg distribution and disease reactivation. Interestingly, a secondary inoculation with L. braziliensis did not preclude an efficient recall response to L. braziliensis at a distal site, despite the presence of Tregs. Within dLNs, reinfection did not promote parasite dissemination or a differential recruitment of either CD4(+)CD25(+)Foxp3(+) or CD4(+)IL-10(+) T cells. On the contrary, parasites were mainly detected in the LN draining the primary infection site where a high frequency of CD4(+)IFN-γ(+) T cells was also present. Collectively these data show that during experimental infection, Tregs are present in healed mice but this population does not compromise an effective immune response upon reinfection with L. braziliensis.
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Imunidade , Leishmania braziliensis/fisiologia , Leishmaniose/imunologia , Leishmaniose/parasitologia , Linfócitos T Reguladores/imunologia , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB CRESUMO
BACKGROUND: Vaccine development has been a priority in the fight against leishmaniases, which are vector-borne diseases caused by Leishmania protozoa. Among the different immunization strategies employed to date is inoculation of plasmid DNA coding for parasite antigens, which has a demonstrated ability to induce humoral and cellular immune responses. In this sense, inoculation of plasmid DNA encoding Leishmania kinetoplasmid membrane protein-11 (KMP-11) was able to confer protection against visceral leishmaniasis. However, recently the use of antigen delivery systems such as poly(lactic-co-glycolic acid) (PLGA) nanoparticles has also proven effective for eliciting protective immune responses. METHODS: In the present work, we tested two immunization strategies with the goal of obtaining protection, in terms of lesion development and parasite load, against cutaneous leishmaniasis caused by L. braziliensis. One strategy involved immunization with plasmid DNA encoding L. infantum chagasi KMP-11. Alternatively, mice were primed with PLGA nanoparticles loaded with the recombinant plasmid DNA and boosted using PLGA nanoparticles loaded with recombinant KMP-11. RESULTS: Both immunization strategies elicited detectable cellular immune responses with the presence of both proinflammatory and anti-inflammatory cytokines; mice receiving the recombinant PLGA nanoparticle formulations also demonstrated anti-KMP-11 IgG1 and IgG2a. Mice were then challenged with L. braziliensis, in the presence of sand fly saliva. Lesion development was not inhibited following either immunization strategy. However, immunization with PLGA nanoparticles resulted in a more prominent reduction in parasite load at the infection site when compared with immunization using plasmid DNA alone. This effect was associated with a local increase in interferon-gamma and in tumor necrosis factor-alpha. Both immunization strategies also resulted in a lower parasite load in the draining lymph nodes, albeit not significantly. CONCLUSION: Our results encourage the pursuit of immunization strategies employing nanobased delivery systems for vaccine development against cutaneous leishmaniasis caused by L. braziliensis infection.
Assuntos
Vacinas contra Leishmaniose/administração & dosagem , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/prevenção & controle , Animais , Anticorpos Antiprotozoários/biossíntese , Antígenos de Protozoários/administração & dosagem , Citocinas/metabolismo , Sistemas de Liberação de Medicamentos , Feminino , Imunidade Celular , Ácido Láctico/química , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Nanomedicina , Nanopartículas/administração & dosagem , Nanopartículas/química , Plasmídeos/administração & dosagem , Plasmídeos/genética , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteínas de Protozoários/administração & dosagem , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Vacinas de DNA/administração & dosagemRESUMO
BACKGROUND: Nitric oxide (NO) produced in macrophages plays a pivotal role as a leishmanicidal agent. A previous study has demonstrated that 20% of the L. (V.) braziliensis isolated from initial cutaneous lesions of patients from the endemic area of Corte de Pedra, Bahia, Brazil, were NO resistant. Additionally, 5 to 11% of the patients did not respond to three or more antimony treatments" (refractory patients). The aim of this study is to investigate if there is an association between the resistance of L. (V.) braziliensis to NO and nonresponsiveness to antimony therapy and cytokine production. METHODS: We evaluated the in vitro toxicity of NO against the promastigotes stages of L. (V.) braziliensis isolated from responsive and refractory patients, and the infectivity of the amastigote forms of these isolates against human macrophages. The supernatants from Leishmania infected macrophage were used to measure TNF-alpha and IL-10 levels. RESULTS: Using NaNO2 (pH 5.0) as the NO source, L. (V.) braziliensis isolated from refractory patients were more NO resistant (IC50 = 5.8 +/- 4.8) than L. (V.) braziliensis isolated from responsive patients (IC50 = 2.0 +/- 1.4). Four isolates were selected to infect human macrophages: NO-susceptible and NO-resistant L. (V.) braziliensis isolated from responsive and refractory patients. NO-resistant L. (V.) braziliensis isolated from refractory patients infected more macrophages stimulated with LPS and IFN-gamma at 120 hours than NO-susceptible L. (V.) braziliensis isolated from refractory patients. Also, lower levels of TNF-alpha were detected in supernatants of macrophages infected with NO-resistant L. (V.) braziliensis as compared to macrophages infected with NO-susceptible L. (V.) braziliensis (p < 0.05 at 2, 24 and 120 hours), while no differences were detected in IL-10 levels. CONCLUSION: These data suggest that NO resistance could be related to the nonresponsiveness to antimony therapy seen in American Tegumentary Leishmaniasis.
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Antimônio/uso terapêutico , Antiprotozoários/uso terapêutico , Resistência a Medicamentos , Leishmania braziliensis/efeitos dos fármacos , Leishmania braziliensis/imunologia , Óxido Nítrico/toxicidade , Fator de Necrose Tumoral alfa/imunologia , Brasil , Células Cultivadas , Humanos , Interleucina-10/imunologia , Interleucina-10/metabolismo , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea , Macrófagos/imunologia , Macrófagos/parasitologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: During blood feeding, sand flies inject Leishmania parasites in the presence of saliva. The types and functions of cells present at the first host-parasite contact are critical to the outcome on infection and sand fly saliva has been shown to play an important role in this setting. Herein, we investigated the in vivo chemotactic effects of Lutzomyia intermedia saliva, the vector of Leishmania braziliensis, combined or not with the parasite. METHODS AND FINDINGS: We tested the initial response induced by Lutzomyia intermedia salivary gland sonicate (SGS) in BALB/c mice employing the air pouch model of inflammation. L. intermedia SGS induced a rapid influx of macrophages and neutrophils. In mice that were pre-sensitized with L. intermedia saliva, injection of SGS was associated with increased neutrophil recruitment and a significant up-regulation of CXCL1, CCL2, CCL4 and TNF-alpha expression. Surprisingly, in mice that were pre-exposed to SGS, a combination of SGS and L. braziliensis induced a significant migration of neutrophils and an important modulation in cytokine and chemokine expression as shown by decreased CXCL10 expression and increased IL-10 expression. CONCLUSION: These results confirm that sand fly saliva modulates the initial host response. More importantly, pre-exposure to L. intermedia saliva significantly modifies the host's response to L. braziliensis, in terms of cellular recruitment and expression of cytokines and chemokines. This particular immune modulation may, in turn, favor parasite multiplication.