Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Chem Biodivers ; 21(2): e202301333, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38116898

RESUMO

Propolis is one functional supplement with hundreds of years of usage. However, it's rarely consumed directly for its resinous property. Herein, a pre-treated process which can remove the impurity while preserve its bioactivities is needed to maximise its therapeutic opportunities. In the present study, a membrane-based ultrafiltration process was developed on a KM1812-NF experimental instrument. Using Brazilian green propolis as testing material, all experimental steps and parameters were sequentially optimized. In addition, a mathematical model was developed to fit the process. As a result, the optimum solvent was 60 % ethanol adjusted to pH 8-9, while the optimum MWCO (molecular weight cut-off) value of membrane was 30 KDa. The membrane filtration dynamic model fitted with the function y=(ax+b)/(1+cx+dx2 ). The resulting propolis ultrafiltrate from Brazilian green propolis, termed P30K, contains the similar profile of flavonoids and phenolic acids as raw propolis. Meanwhile, the ORAC (oxygen radical absorbance capacity) value of P30K is 11429.45±1557.58 µM TE/g and the IC50 value of inhibition of fluorescent AGEs (advanced glycation end products) formation is 0.064 mg/mL. Our work provides an innovative alternative process for extraction of active compounds from propolis and reveals P30K as an efficient therapeutic antioxidant.


Assuntos
Antioxidantes , Própole , Antioxidantes/farmacologia , Antioxidantes/química , Própole/farmacologia , Própole/química , Flavonoides/química , Etanol/química , Solventes
2.
Chem Biodivers ; 21(3): e202301315, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38189169

RESUMO

Thousands of years ago, humans started to use propolis because of its medicinal properties, and modern science has successfully identified several bioactive molecules within this resinous bee product. However, a natural propolis extract which has been removed the adhesive glue and preserved propolis bioactive compounds is urgently needed to maximise the therapeutic opportunities. In this study, a novel ultrafiltrate fraction from Brazilian green propolis, termed P30K, was demonstrated with anti-inflammatory properties, both in vitro and in vivo. Total flavonoids and total phenolic acids content in P30K were 244.6 mg/g and 275.8 mg/g respectively, while the IC50 value of inhibition of cyclooxygenase-2 (COX-2) was 8.30 µg/mL. The anti-inflammatory activity of P30K was furtherly corroborated in experimental models of lipopolysaccharides (LPS)-induced acute liver and lung injury. Mechanistically, integrated GC-MS and LC-MS based serum metabolomics analysis revealed that P30K modulated citrate cycle (TCA), pyruvate, glyoxylate and dicarboxylate metabolism pathways to inhibit secretion of pro-inflammatory cytokines. Results of network pharmacology and molecular docking suggested that P30K targeted catechol-O-methyltransferases (COMT), 11ß-hydroxysteroid dehydrogenases (HSD11B1), and monoamine oxidases (MAOA and MAOB) to promote cellular metabolomic rewiring. Collectively, our work reveals P30K as an efficient therapeutic agent against inflammatory conditions and its efficacy is related to metabolic rewiring.


Assuntos
Própole , Humanos , Própole/farmacologia , Simulação de Acoplamento Molecular , Flavonoides/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Brasil
3.
PLoS Pathog ; 17(11): e1010069, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748611

RESUMO

ES-62 is the major secreted protein of the parasitic filarial nematode, Acanthocheilonema viteae. The molecule exists as a large tetramer (MW, ~240kD), which possesses immunomodulatory properties by virtue of multiple phosphorylcholine (PC) moieties attached to N-type glycans. By suppressing inflammatory immune responses, ES-62 can prevent disease development in certain mouse models of allergic and autoimmune conditions, including joint pathology in collagen-induced arthritis (CIA), a model of rheumatoid arthritis (RA). Such protection is associated with functional suppression of "pathogenic" hyper-responsive synovial fibroblasts (SFs), which exhibit an aggressive inflammatory and bone-damaging phenotype induced by their epigenetic rewiring in response to the inflammatory microenvironment of the arthritic joint. Critically, exposure to ES-62 in vivo induces a stably-imprinted CIA-SF phenotype that exhibits functional responses more typical of healthy, Naïve-SFs. Consistent with this, ES-62 "rewiring" of SFs away from the hyper-responsive phenotype is associated with suppression of ERK activation, STAT3 activation and miR-155 upregulation, signals widely associated with SF pathogenesis. Surprisingly however, DNA methylome analysis of Naïve-, CIA- and ES-62-CIA-SF cohorts reveals that rather than simply preventing pathogenic rewiring of SFs, ES-62 induces further changes in DNA methylation under the inflammatory conditions pertaining in the inflamed joint, including targeting genes associated with ciliogenesis, to programme a novel "resolving" CIA-SF phenotype. In addition to introducing a previously unsuspected aspect of ES-62's mechanism of action, such unique behaviour signposts the potential for developing DNA methylation signatures predictive of pathogenesis and its resolution and hence, candidate mechanisms by which novel therapeutic interventions could prevent SFs from perpetuating joint inflammation and destruction in RA. Pertinent to these translational aspects of ES-62-behavior, small molecule analogues (SMAs) based on ES-62's active PC-moieties mimic the rewiring of SFs as well as the protection against joint disease in CIA afforded by the parasitic worm product.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/prevenção & controle , Epigênese Genética , Fibroblastos/metabolismo , Proteínas de Helminto/farmacologia , Inflamação/prevenção & controle , Sinoviócitos/metabolismo , Acanthocheilonema/metabolismo , Animais , Artrite Experimental/etiologia , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Células Cultivadas , Metilação de DNA , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos DBA , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/imunologia
4.
Cell Immunol ; 387: 104717, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37075620

RESUMO

CD20+ T cells comprise a highly inflammatory subset implicated in autoimmunity, including rheumatoid arthritis (RA). We sought to characterize the CD20+ T cell subset in the murine collagen-induced arthritis (CIA) model of RA and investigate the phenotype and functional relevance of CD3+CD20+ T cells in the lymph nodes and arthritic joints using flow cytometry and immunohistochemistry. We demonstrate that CD3+CD4+CD20+ and CD3+CD8+CD20+ T cells are expanded in the draining lymph nodes of CIA mice, produce increased levels of pro-inflammatory cytokines and are less susceptible to regulation by regulatory T cells. Notably, CD3+CD4+CD20+ and CD3+CD8+CD20+ T cells are enriched with CXCR5+PD-1+ T follicular helper cells and CXCR5-PD-1+ peripheral T helper cells, subsets of T cells implicated in promoting B-cell responses and antibody production within pathologically inflamed non-lymphoid tissues in RA. Our findings suggest CD20+ T cells are associated with inflammatory responses and may exacerbate pathology by promoting inflammatory B-cell responses.


Assuntos
Artrite Experimental , Artrite Reumatoide , Animais , Camundongos , Receptor de Morte Celular Programada 1 , Linfócitos T Auxiliares-Indutores , Subpopulações de Linfócitos T , Receptores CXCR5
5.
PLoS Pathog ; 16(3): e1008391, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32163524

RESUMO

Improvements in hygiene and health management have driven significant increases in human lifespan over the last 50 years. Frustratingly however, this extension of lifespan has not been matched by equivalent improvements in late-life health, not least due to the global pandemic in type-2 diabetes, obesity and cardiovascular disease, all ageing-associated conditions exacerbated and accelerated by widespread adoption of the high calorie Western diet (HCD). Recently, evidence has begun to emerge that parasitic worm infection might protect against such ageing-associated co-morbidities, as a serendipitous side-effect of their evolution of pro-survival, anti-inflammatory mechanisms. As a novel therapeutic strategy, we have therefore investigated the potential of ES-62, an anti-inflammatory secreted product of the filarial nematode Acanthocheilonema viteae, to improve healthspan (the period of life before diseases of ageing appear) by targeting the chronic inflammation that drives metabolic dysregulation underpinning ageing-induced ill-health. We administered ES-62 subcutaneously (at a dose of 1 µg/week) to C57BL/6J mice undergoing HCD-accelerated ageing throughout their lifespan, while subjecting the animals to analysis of 120 immunometabolic responses at various time-points. ES-62 improved a number of inflammatory parameters, but markedly, a range of pathophysiological, metabolic and microbiome parameters of ageing were also successfully targeted. Notably, ES-62-mediated promotion of healthspan in male and female HCD-mice was associated with different mechanisms and reflecting this, machine learning modelling identified sex-specific signatures predictive of ES-62 action against HCD-accelerated ageing. Remarkably, ES-62 substantially increased the median survival of male HCD-mice. This was not the case with female animals and unexpectedly, this difference between the two sexes could not be explained in terms of suppression of the chronic inflammation driving ageing, as ES-62 tended to be more effective in reducing this in female mice. Rather, the difference appeared to be associated with ES-62's additional ability to preferentially promote a healthier gut-metabolic tissue axis in male animals.


Assuntos
Acanthocheilonema/imunologia , Acantoqueilonemíase/imunologia , Dieta Ocidental/efeitos adversos , Proteínas de Helminto/imunologia , Longevidade/imunologia , Modelos Imunológicos , Animais , Feminino , Masculino , Camundongos
6.
Immunology ; 164(1): 3-14, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33763853

RESUMO

Urinary tract infections (UTI) are among the most prevalent infectious diseases and the most common cause of nosocomial infections, worldwide. Uropathogenic E. coli (UPEC) are responsible for approximately 80% of all UTI, which most commonly affect the bladder. UPEC colonize the urinary tract by ascension of the urethra, followed by cell invasion, and proliferation inside and outside urothelial cells, thereby causing symptomatic infections and quiescent intracellular reservoirs that may lead to recurrence. Sugars, or glycans, are key molecules for host-pathogen interactions, and UTI are no exception. Surface glycans regulate many of the events associated with UPEC adhesion and infection, as well as induction of the host immune response. While the bacterial protein FimH binds mannose-containing host glycoproteins to initiate infection and UPEC-secreted polysaccharides block immune mechanisms to favour intracellular replication, host glycans on the urothelial surface and on secreted glycoproteins prevent or limit infection by inhibiting UPEC adhesion. Given the importance of glycans during UTI, here we review the glycobiology of UPEC infection to highlight fundamental sugar-mediated processes of immunological interest for their potential clinical applications. Interdisciplinary approaches incorporating glycomics and infection biology may help to develop novel non-antibiotic-based therapeutic strategies for bacterial infections as the spread of antimicrobial-resistant uropathogens is currently threatening modern healthcare systems.


Assuntos
Polissacarídeos/metabolismo , Sistema Urinário/imunologia , Escherichia coli Uropatogênica/fisiologia , Animais , Infecções por Escherichia coli , Glicômica , Interações Hospedeiro-Patógeno , Humanos , Polissacarídeos/imunologia , Infecções Urinárias , Virulência
7.
Parasite Immunol ; 43(3): e12803, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33091157

RESUMO

AIMS: ES-62 is a well-studied anti-inflammatory molecule secreted by L4-adult stage Acanthocheilonema viteae. We maintain the life cycle of A viteae using Meriones libycus as the definitive host. Here, we investigated whether the full life cycle could be maintained, and functional ES-62 produced, in a related jird species-Meriones shawi. METHODS AND RESULTS: Adult worms were produced in comparable numbers in the two species, but very few microfilariae (MF) were observed in the M shawi bloodstream. M shawi ES-62 produced ex vivo was functional and protective in a mouse model of arthritis. Myeloid-derived cells from naïve and infected jirds of both species were compared with respect to ROS production and osteoclast generation, and some differences between the two species in both the absence and presence of infection were observed. CONCLUSIONS: The life cycle of A viteae cannot be successfully completed in M shawi jirds but L3 stage worms develop to adulthood and produce functional ES-62. Preliminary investigation into jird immune responses suggests that infection can differentially modulate myeloid responses in the two species. However, species-specific reagents are required to understand the complex interplay between A viteae and its host and to explain the lack of circulating MF in infected M shawi jirds.


Assuntos
Acanthocheilonema/crescimento & desenvolvimento , Acantoqueilonemíase/parasitologia , Gerbillinae/parasitologia , Proteínas de Helminto/biossíntese , Animais , Modelos Animais de Doenças , Feminino , Estágios do Ciclo de Vida , Masculino , Camundongos , Microfilárias/crescimento & desenvolvimento , Especificidade da Espécie
8.
Sensors (Basel) ; 19(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288378

RESUMO

Existing correlations between features extracted from Electroencephalography (EEG) signals and emotional aspects have motivated the development of a diversity of EEG-based affect detection methods. Both intra-subject and inter-subject approaches have been used in this context. Intra-subject approaches generally suffer from the small sample problem, and require the collection of exhaustive data for each new user before the detection system is usable. On the contrary, inter-subject models do not account for the personality and physiological influence of how the individual is feeling and expressing emotions. In this paper, we analyze both modeling approaches, using three public repositories. The results show that the subject's influence on the EEG signals is substantially higher than that of the emotion and hence it is necessary to account for the subject's influence on the EEG signals. To do this, we propose a data transformation that seamlessly integrates individual traits into an inter-subject approach, improving classification results.


Assuntos
Eletroencefalografia/métodos , Emoções/fisiologia , Modelos Biológicos , Processamento de Sinais Assistido por Computador , Nível de Alerta/fisiologia , Análise de Dados , Bases de Dados Factuais , Humanos , Máquina de Vetores de Suporte
9.
Entropy (Basel) ; 20(11)2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33266535

RESUMO

Catalytic surface reaction networks exhibit nonlinear dissipative phenomena, such as bistability. Macroscopic rate law descriptions predict that the reaction system resides on one of the two steady-state branches of the bistable region for an indefinite period of time. However, the smaller the catalytic surface, the greater the influence of coverage fluctuations, given that their amplitude normally scales as the square root of the system size. Thus, one can observe fluctuation-induced transitions between the steady-states. In this work, a model for the bistable catalytic CO oxidation on small surfaces is studied. After a brief introduction of the average stochastic modelling framework and its corresponding deterministic limit, we discuss the non-equilibrium conditions necessary for bistability. The entropy production rate, an important thermodynamic quantity measuring dissipation in a system, is compared across the two approaches. We conclude that, in our catalytic model, the most favorable non-equilibrium steady state is not necessary the state with the maximum or minimum entropy production rate.

10.
J Sex Med ; 14(5): 731-737, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28400085

RESUMO

BACKGROUND: A successful penile prosthesis implantation (PPI) surgery can be defined by outcomes beyond the absence of complications. AIM: To introduce the concept of failure to cure (FTC) in the context of PPI to more accurately gauge postoperative outcomes after PPI. METHODS: Consecutive patients from our sexual function registry who underwent PPI from January 2011 to December 2013 were analyzed. Demographics, previous treatment of erectile dysfunction, comorbidities, social history, postoperative problems (POPs), and surgical outcomes were tabulated. Patients completed the International Index of Erection Function (IIEF) and the Erectile Dysfunction Inventory of Treatment Satisfaction questionnaires. We defined a complication, according to the Clavien-Dindo classification, as any deviation from the ideal postoperative course that is not inherent in the procedure and does not constitute an FTC. FTC was defined as a POP that was not a complication. The χ2 tests, t-tests, or Wilcoxon rank-sum tests were used. OUTCOMES: Patient-reported and objective outcomes after PPI. RESULTS: Our enrollment consisted of 185 patients, and we contacted 124 (67%). Of these, 16 (12.9%) had a POP requiring reoperation. Eight patients developed surgical complications (three infections, four erosions, and one chronic pain). Eight patients had FTC (four malpositions and four malfunctions). Factors that correlated with POPs were previous PPI, body mass index higher than 30 kg/m2, and previous treatment with intracorporal injections (P < .05 for all comparisons). Patients who had POPs scored significantly lower on the IIEF erectile function and intercourse satisfaction domains (P < .05 for the two comparisons), but not on the orgasmic function, sexual desire, and overall satisfaction domains (P > .05 for all comparisons). CLINICAL IMPLICATIONS: POPs after PPI surgery can be more accurately categorized using the Clavien-Dindo classification of surgical complications to more clearly distinguish surgical complications from FTC. STRENGTHS AND LIMITATIONS: Limitations of our study include its retrospective approach. Our series included a large proportion of patients treated for prostate cancer, which limits the generalizability of our findings. We also had a relatively short median follow-up time of 27 months. CONCLUSIONS: Patient-reported outcome assessments can vary greatly from what physicians determine to be successful PPI. An assessment of POPs encompasses more than just complication rates; it also reflects FTC. Even when POPs occur, patients can still derive satisfaction if they are correctively managed. Factors that possibly predispose to POPs include previous PPI surgery, body mass index greater than 30 kg/m2, and history of intracorporal injections. Pineda M, Burnett AL. Distinguishing Failure to Cure From Complication After Penile Prosthesis Implantation. J Sex Med 2017;14:731-737.


Assuntos
Implante Peniano/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Disfunção Erétil/epidemiologia , Humanos , Libido , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Pênis/cirurgia , Estudos Retrospectivos , Estatísticas não Paramétricas , Resultado do Tratamento
11.
J Sex Med ; 14(3): 455-463, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28189561

RESUMO

INTRODUCTION: Penile prosthesis infections remain challenging despite advancements in surgical technique, device improvements, and adoption of antibiotic prophylaxis guidelines. AIM: To investigate penile prosthesis infection microbiology to consider which changes in practice could decrease infection rates, to evaluate current antibiotic prophylaxis guidelines, and to develop a proposed algorithm for penile prosthesis infections. METHODS: This retrospective institutional review board-exempt multi-institutional study from 25 centers reviewed intraoperative cultures obtained at explantation or Mulcahy salvage of infected three-piece inflatable penile prostheses (IPPs). Antibiotic usage was recorded at implantation, admission for infection, and explantation or salvage surgery. Cultures were obtained from purulent material in the implant space and from the biofilm on the device. MAIN OUTCOME MEASURES: Intraoperative culture data from infected IPPs. RESULTS: Two hundred twenty-seven intraoperative cultures (2002-2016) were obtained at salvage or explantation. No culture growth occurred in 33% of cases and gram-positive and gram-negative organisms were found in 73% and 39% of positive cultures, respectively. Candida species (11.1%), anaerobes (10.5%) and methicillin-resistant Staphylococcus aureus (9.2%) constituted nearly one third of 153 positive cultures. Multi-organism infections occurred in 25% of positive cultures. Antibiotic regimens at initial implantation were generally consistent with American Urological Association (AUA) and European Association of Urology (EAU) guidelines. However, the micro-organisms identified in this study were covered by these guidelines in only 62% to 86% of cases. Antibiotic selection at admissions for infection and salvage or explantation varied widely compared with those at IPP implantation. CONCLUSION: This study documents a high incidence of anaerobic, Candida, and methicillin-resistant S aureus infections. In addition, approximately one third of infected penile prosthesis cases had negative cultures. Micro-organisms identified in this study were not covered by the AUA and EAU antibiotic guidelines in at least 14% to 38% of cases. These findings suggest broadening antibiotic prophylaxis guidelines and creating a management algorithm for IPP infections might lower infection rates and improve salvage success. Gross MS, Phillips EA, Carrasquillo RJ, et al. Multicenter Investigation of the Micro-Organisms Involved in Penile Prosthesis Infection: An Analysis of the Efficacy of the AUA and EAU Guidelines for Penile Prosthesis Prophylaxis. J Sex Med 2017;14:455-463.


Assuntos
Antibioticoprofilaxia , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/prevenção & controle , Antibacterianos/uso terapêutico , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina , Prótese de Pênis/efeitos adversos , Reoperação/efeitos adversos , Estudos Retrospectivos
12.
Sensors (Basel) ; 17(2)2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28134753

RESUMO

Wireless Sensor Networks (WSNs) are composed of spatially distributed autonomous sensor devices, named motes. These motes have their own power supply, processing unit, sensors and wireless communications However with many constraints, such as limited energy, bandwidth and computational capabilities. In these networks, at least one mote called a sink, acts as a gateway to connect with other networks. These sensor networks run monitoring applications and then the data gathered by these motes needs to be retrieved by the sink. When this sink is located in the far field, there have been many proposals in the literature based on Collaborative Beamforming (CB), also known as Distributed or Cooperative Beamforming, for these long range communications to reach the sink. In this paper, we conduct a thorough study of the related work and analyze the requirements to do CB. In order to implement these communications in real scenarios, we will consider if these requirements and the assumptions made are feasible from the point of view of commercial motes and their constraints. In addition, we will go a step further and will consider different alternatives, by relaxing these requirements, trying to find feasible assumptions to carry out these types of communications with commercial motes. This research considers the nonavailability of a central clock that synchronizes all motes in the WSN, and all motes have identical hardware. This is a feasibility study to do CB on WSN, using a simulated scenario with randomized delays obtained from experimental data from commercial motes.

13.
Arthroscopy ; 32(4): 651-68.e1, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26524934

RESUMO

PURPOSE: To perform a systematic review of cartilage repair in athletes' knees to (1) determine which (if any) of the most commonly implemented surgical techniques help athletes return to competition, (2) identify which patient- or defect-specific characteristics significantly affect return to sport, and (3) evaluate the methodologic quality of available literature. METHODS: A systematic review of multiple databases was performed. Return to preinjury level of sport was defined as the ability to play in the same or greater level (i.e., league or division) of competition after surgery. Study methodologic quality for all studies analyzed in this review was evaluated with the Coleman Methodology Score. RESULTS: Systematic review of 1,278 abstracts identified 20 level I-IV studies for inclusion but only 1 randomized controlled trial. Twenty studies (1,117 subjects) were included. Subjects (n = 970) underwent 1 of 4 surgeries (microfracture [n = 529], autologous chondrocyte implantation [ACI, n = 259], osteochondral autograft [n = 139], or osteochondral allograft [n = 43]), and 147 were control patients. The rate of return to sports was greatest after osteochondral autograft transplantation (89%) followed by osteochondral allograft, ACI, and microfracture (88%, 84%, and 75%, respectively). Osteochondral autograft transplantation and ACI had statistically significantly greater rates of return to sports compared with microfracture (P < .001, P < .01; Fisher exact test). CONCLUSIONS: Athletes may return to sports participation after microfracture, ACI, osteochondral autograft, or osteochondral allograft, but microfracture patients were least likely to return to sports. The athletes who had a better prognosis after surgery were younger, had a shorter preoperative duration of symptoms, underwent no previous surgical interventions, participated in a more rigorous rehabilitation protocol, and had smaller cartilage defects. LEVEL OF EVIDENCE: Level IV, systematic review of Level I-IV studies.


Assuntos
Traumatismos em Atletas/cirurgia , Cartilagem Articular/cirurgia , Procedimentos Ortopédicos/métodos , Volta ao Esporte , Traumatismos em Atletas/reabilitação , Cartilagem Articular/lesões , Humanos
14.
J Infect Dis ; 212(7): 1160-71, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25805753

RESUMO

BACKGROUND: Chagas disease is caused by the protozoan Trypanosoma cruzi, affecting millions of people worldwide. One of the major causes of mortality in the disease is the cardiomyopathy observed in chronic patients, despite the low number of parasites detected in cardiac tissue. Galectin-3, a carbohydrate-binding protein with affinity for ß-galactoside-containing glycoconjugates, is upregulated upon infection, and it has been recently involved in the pathophysiology of heart failure. METHODS: We investigated the role of galectin-3 in systemic and local responses in a murine model of T. cruzi infection, using knockout animals. Molecular mechanisms underlying galectin-3-dependent inflammatory responses were further assessed in cultured dendritic cells in vitro. RESULTS: Mice deficient for galectin-3 have elevated blood parasitemia levels and impaired cytokine production during infection. Remarkably, galectin-3 promotes cellular infiltration in the heart of infected mice and subsequent collagen deposition and cardiac fibrosis. Furthermore, we show that an unbalanced Toll-like receptor expression on antigen-presenting cells may be the cause of the impaired immune response observed in galectin-3-deficient mice in vivo. CONCLUSIONS: These results suggest that galectin-3 is strongly involved in Chagas disease, not only in the immune response against T. cruzi, but also in mediating cardiac tissue damage.


Assuntos
Doença de Chagas/imunologia , Galectina 3/imunologia , Imunidade Inata/imunologia , Miocárdio/patologia , Trypanosoma cruzi/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/prevenção & controle , Doença de Chagas/parasitologia , Chlorocebus aethiops , Fibrose/imunologia , Fibrose/prevenção & controle , Galactosídeos/imunologia , Galectina 3/metabolismo , Humanos , Camundongos , Camundongos Knockout , Miocárdio/imunologia , Parasitemia , Receptores de Superfície Celular/imunologia , Receptores Toll-Like/imunologia , Células Vero
15.
Ann Rheum Dis ; 79(12): 1659-1661, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32606046
16.
J Autoimmun ; 60: 59-73, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25975491

RESUMO

Rheumatoid arthritis (RA) remains a debilitating autoimmune condition as many patients are refractory to existing conventional and biologic therapies, and hence successful development of novel treatments remains a critical requirement. Towards this, we now describe a synthetic drug-like small molecule analogue, SMA-12b, of an immunomodulatory parasitic worm product, ES-62, which acts both prophylactically and therapeutically against collagen-induced arthritis (CIA) in mice. Mechanistic analysis revealed that SMA-12b modifies the expression of a number of inflammatory response genes, particularly those associated with the inflammasome in mouse bone marrow-derived macrophages and indeed IL-1ß was the most down-regulated gene. Consistent with this, IL-1ß was significantly reduced in the joints of mice with CIA treated with SMA-12b. SMA-12b also increased the expression of a number of genes associated with anti-oxidant responses that are controlled by the transcription factor NRF2 and critically, was unable to inhibit expression of IL-1ß by macrophages derived from the bone marrow of NRF2(-/-) mice. Collectively, these data suggest that SMA-12b could provide the basis of an entirely novel approach to fulfilling the urgent need for new treatments for RA.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Proteínas de Helminto/farmacologia , Interleucina-1beta/biossíntese , Fator 2 Relacionado a NF-E2/genética , Acanthocheilonema/metabolismo , Animais , Artrite Experimental/prevenção & controle , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/prevenção & controle , Colágeno , Gerbillinae , Inflamassomos/imunologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Articulações/imunologia , Articulações/patologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/imunologia
17.
Exp Parasitol ; 158: 18-22, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25836375

RESUMO

ES-62 is the major secreted protein of the rodent filarial nematode Acanthocheilonema viteae. The molecule contains covalently attached phosphorylcholine (PC) residues, which confer anti-inflammatory properties on ES-62, underpinning the idea that drugs based on this active moiety may have therapeutic potential in human diseases associated with aberrant inflammation. Here we demonstrate that two synthetic small molecule analogues (SMAs) of ES-62 termed SMA 11a and SMA 12b are protective in the oxazolone-induced acute allergic contact dermatitis mouse model of skin inflammation, as measured by a significant reduction in ear inflammation following their administration before oxazolone sensitisation and before oxazolone challenge. Furthermore, it was found that when tested, 12b was effective at reducing ear swelling even when first administered before challenge. Histological analysis of the ears showed elevated cellular infiltration and collagen deposition in oxazolone-treated mice both of which were reduced by treatment with the two SMAs. Likewise, the oxazolone-induced increase in IFNγ mRNA in the ears was reduced but no effect on other cytokines investigated was observed. Finally, no influence on the mast cell populations in the ear was observed.


Assuntos
Acanthocheilonema/imunologia , Dermatite Alérgica de Contato/imunologia , Proteínas de Helminto/imunologia , Otite Externa/prevenção & controle , Adjuvantes Imunológicos/toxicidade , Animais , Dermatite Alérgica de Contato/parasitologia , Dermatite Alérgica de Contato/prevenção & controle , Modelos Animais de Doenças , Proteínas de Helminto/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Otite Externa/induzido quimicamente , Otite Externa/patologia , Oxazolona/toxicidade , Reação em Cadeia da Polimerase em Tempo Real
18.
Immunology ; 141(3): 457-66, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24708419

RESUMO

We have previously reported that ES-62, a molecule secreted by the parasitic filarial nematode Acanthocheilonema viteae, protects mice from developing collagen-induced arthritis (CIA). Together with increasing evidence that worm infection may protect against autoimmune conditions, this raises the possibility that ES-62 may have therapeutic potential in rheumatoid arthritis and hence, it is important to fully understand its mechanism of action. To this end, we have established to date that ES-62 protection in CIA is associated with suppressed T helper type 1 (Th1)/Th17 responses, reduced collagen-specific IgG2a antibodies and increased interleukin-10 (IL-10) production by splenocytes. IL-10-producing regulatory B cells have been proposed to suppress pathogenic Th1/Th17 responses in CIA: interestingly therefore, although the levels of IL-10-producing B cells were decreased in the spleens of mice with CIA, ES-62 was found to restore these to the levels found in naive mice. In addition, exposure to ES-62 decreased effector B-cell, particularly plasma cell, infiltration of the joints, and such infiltrating B cells showed dramatically reduced levels of Toll-like receptor 4 and the activation markers, CD80 and CD86. Collectively, this induction of hyporesponsiveness of effector B-cell responses, in the context of the resetting of the levels of IL-10-producing B cells, is suggestive of a modulation of the balance between effector and regulatory B-cell responses that may contribute to ES-62-mediated suppression of CIA-associated inflammation and inhibition of production of pathogenic collagen-specific IgG2a antibodies.


Assuntos
Antirreumáticos/farmacologia , Artrite Experimental/prevenção & controle , Linfócitos B/efeitos dos fármacos , Colágeno , Proteínas de Helminto/farmacologia , Interleucina-10/metabolismo , Articulações/efeitos dos fármacos , Plasmócitos/efeitos dos fármacos , Animais , Anticorpos/metabolismo , Antígenos CD/metabolismo , Artrite Experimental/sangue , Artrite Experimental/induzido quimicamente , Artrite Experimental/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores/metabolismo , Células Cultivadas , Colágeno/imunologia , Articulações/imunologia , Articulações/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos DBA , Plasmócitos/imunologia , Plasmócitos/metabolismo , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo , Receptor 4 Toll-Like/metabolismo
19.
Front Trop Dis ; 42024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38500783

RESUMO

The parasitic worm-derived immunomodulator, ES-62 rescues defective levels of IL-10-producing regulatory B cells (Bregs) and suppresses chronic Th1/Th17-driven inflammation to protect against joint destruction in the mouse collagen-induced arthritis (CIA) model of rheumatoid arthritis. Such autoimmune arthritis is also associated with dysbiosis of the gut microbiota and disruption of intestinal barrier integrity. We recently further exploited the CIA model to show that ES-62's prevention of joint destruction is associated with protection of intestinal barrier integrity and normalization of the gut microbiota, thereby suppressing the gut pathology that precedes the onset of autoimmunity and joint damage in CIA-mice. As the status of the gut microbiota impacts on immune responses by influencing haematopoiesis, we have therefore investigated whether ES-62 harnesses the homeostatic mechanisms regulating this gut-bone marrow (BM) axis to resolve the chronic inflammation promoting autoimmunity and joint destruction in CIA. Reflecting this, ES-62 was found to counteract the BM myeloid/lymphoid bias typically associated with chronic inflammation and infection. This was achieved primarily by ES-62 acting to maintain the levels of lymphoid lineages (B220+ and CD3+ cells) observed in naïve, healthy mice but lost from the BM of CIA-mice. Moreover, ES-62's ability to prevent bone-destroying osteoclastogenesis was found to be associated with its suppression of CIA-induced upregulation of osteoclast progenitors (OCPs) in the BM. Critically, and supporting ES-62's targeting of the gut-BM axis, this rewiring of inflammatory haematopoiesis was lost in mice with a depleted microbiome. Underlining the importance of ES-62's actions in restoring steady-state haematopoiesis, the BM levels of B and T lymphoid cells were shown to be inversely correlated, whilst the levels of OCPs positively correlated, with the severity of joint damage in CIA-mice.

20.
Commun Biol ; 7(1): 804, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961129

RESUMO

Oral administration of harmless antigens can induce suppression of reactive immune responses, a process that capitalises on the ability of the gastrointestinal tract to tolerate exposure to food and commensal microbiome without triggering inflammatory responses. Repeating exposure to type II collagen induces oral tolerance and inhibits induction of arthritis, a chronic inflammatory joint condition. Although some mechanisms underlying oral tolerance are described, how dysregulation of gut immune networks impacts on inflammation of distant tissues like the joints is unclear. We used undenatured type II collagen in a prophylactic regime -7.33 mg/kg three times/week- to describe the mechanisms associated with protective oral immune-therapy (OIT) in gut and joint during experimental Collagen-Induced Arthritis (CIA). OIT reduced disease incidence to 50%, with reduced expression of IL-17 and IL-22 in the joints of asymptomatic mice. Moreover, whilst the gut tissue of arthritic mice shows substantial damage and activation of tissue-specific immune networks, oral administration of undenatured type II collagen protects against gut pathology in all mice, symptomatic and asymptomatic, rewiring IL-17/IL-22 networks. Furthermore, gut fucosylation and microbiome composition were also modulated. These results corroborate the relevance of the gut-joint axis in arthritis, showing novel regulatory mechanisms linked to therapeutic OIT in joint disease.


Assuntos
Artrite Experimental , Colágeno Tipo II , Microbioma Gastrointestinal , Homeostase , Animais , Artrite Experimental/imunologia , Artrite Experimental/prevenção & controle , Colágeno Tipo II/imunologia , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Articulações/imunologia , Articulações/efeitos dos fármacos , Articulações/patologia , Camundongos Endogâmicos DBA , Interleucina-17/metabolismo , Interleucina 22 , Administração Oral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA