Artesunate ameliorates experimental autoimmune encephalomyelitis by inhibiting leukocyte migration to the central nervous system

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOExperimental autoimmune encephalomyelitis (EAE) is T-celldependent disease of the central nervous system (CNS) of mice. This model resembles multiple sclerosis (MS) in many aspects. Therapies that focus in the modulation of the immune response and cellular infiltration in the CNS present best effects in the clinics. Artesunate (Art) is a semi-synthetic sesquiterpene derivative from artemisinin and has been shown to reduce the clinical signs of autoimmune disease models through mechanisms not yet understood. In this study, we aimed to evaluate whether administration of Art would ameliorate EAE. Methods and Results: C57BL6 mice were immunized with MOG(35-55) peptide to induce EAE. At the same time, Art treatment started (3 mg/kg/day via i.p.) for five consecutive days. We found that Art treatment reduced the clinical signs of EAE and that correlated with a reduced infiltration of cells in the CNS. Disease amelioration did not correlate with immunomodulation as recall responses, leukocyte subpopulations, and gene expression analysis were similar among treated and untreated mice. Ultimately, further analysis provided data indicating that a possible mechanism of action for Art is dependent on the cellular migration to the CNS. Conclusions: Artesunate reduces the severity of EAE by inhibiting migration of pathogenic T cells to the CNS.Experimental autoimmune encephalomyelitis (EAE) is T-celldependent disease of the central nervous system (CNS) of mice. This model resembles multiple sclerosis (MS) in many aspects. Therapies that focus in the modulation of the immune response and cellula228707714FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO2014/19492-3; 2014/02631-0; 2014/11588-

A importância da abordagem multidisciplinar na Unidade de Terapia Intensiva (UTI): melhorando os resultados clínicos e a qualidade de vida dos pacientes

Introdução: Este presente trabalho tem como intuito destacar a importância da abordagem multidisciplinar na Unidade de Terapia Intensiva (UTI), ressaltando a necessidade de coordenação e colaboração entre os profissionais de saúde. Essa abordagem tem se tornado cada vez mais comum, devido aos benefícios que traz, como melhores resultados clínicos e qualidade de vida para os pacientes. O ensaio também faz uma comparação entre a composição da equipe tradicional e da equipe multidisciplinar na UTI. Metodologia: Foi realizada uma revisão de literatura sobre os resultados clínicos que afetam a qualidade de vida dos pacientes internados em Unidades de Terapia Intensiva (UTI). Foram pesquisados artigos publicados em inglês, espanhol ou português nas bases de dados Pubmed, Scielo e Medline, no período de 2010 a 2022. Foram utilizados descritores específicos na busca e foram incluídos estudos de coorte, estudos de caso-controle e revisões sistemáticas relacionados aos aspectos clínicos e fisiológicos da microbiota intestinal em relação à saúde humana. Discussão: Neste trabalho foi discutido a abordagem multidisciplinar na UTI, tendo como intuito fornecer cuidados de alta qualidade, promovendo a comunicação, a colaboração e o cuidado centrado no paciente. Superar os desafios e implementar essa abordagem exigirá uma ação coletiva. Conclusão: Este estudo concluiu que a abordagem multidisciplinar na UTI é um elemento essencial nos cuidados intensivos modernos e deve ser priorizada em organizações de saúde ao redor do mundo

Gliotoxin Aggravates Experimental Autoimmune Encephalomyelitis by Triggering Neuroinflammation

Gliotoxin (GTX) is the major and the most potent mycotoxin that is secreted by Aspergillus fumigatus, which is capable of injuring and killing microglial cells, astrocytes, and oligodendrocytes. During the last years, studies with patients and experimental models of multiple sclerosis (MS), which is an autoimmune disease of the central nervous system (CNS), suggested that fungal infections are among the possible initiators or aggravators of this pathology. The deleterious effect can occur through a direct interaction of the fungus with the CNS or by the toxin release from a non-neurological site. In the present work, we investigated the effect of GTX on experimental autoimmune encephalomyelitis (EAE) development. Female C57BL/6 mice were immunized with myelin oligodendrocyte glycoprotein and then intraperitoneally injected with three doses of GTX (1 mg/kg b.w., each) on days 4, 7, and 10. GTX aggravated clinical symptoms of the disease in a dose-dependent way and this outcome was concomitant with an increased neuroinflammation. CNS analyses revealed that GTX locally increased the relative expression of inflammatory genes and the cytokine production. Our results indicate that GTX administered in a non-neuronal site was able to increase neuroinflammation in EAE. Other mycotoxins could also be deleterious to many neurological diseases by similar mechanisms

Efeito da infecção com Candida albicans no desenvolvimento da Encefalomielite Autoimune Experimental

A esclerose múltipla é uma doença autoimune ainda sem cura que acomete o sistema nervoso central (SNC). Evidências observadas em pacientes e em modelos experimentais indicam que infecções fúngicas e/ou derivados fúngicos podem contribuir com a patogênese da doença. Neste contexto, o objetivo deste projeto foi avaliar o efeito da infecção por Candida albicans e derivados fúngicos no desenvolvimento da encefalomielite autoimune experimental (EAE) que é o modelo murino desta patologia. Para avaliar o papel da infecção, camundongos C57BL/6 foram infectados com C. albicans três dias antes da indução da EAE. A infecção prévia agravou os sinais clínicos da doença. Este agravamento foi relacionado com a disseminação do fungo para o SNC e aumento da produção de citocinas encefalitogênicas (TNF-a, IL-6, IL-17 e IFN-y) tanto na periferia (baço) quanto no SNC. Para avaliar o efeito de derivados fúngicos no desenvolvimento da EAE, camundongos foram inoculados com três doses de gliotoxina ou de leveduras mortas de C. albicans após a indução da doença. A inoculação de gliotoxina resultou em sintomatologia mais grave, associada com um intenso infiltrado inflamatório e maior produção de TNF-a no SNC. De forma distinta a inoculação de leveduras mortas resultou em uma doença bem mais branda, com menor porcentagem de células apoptóticas e baixa produção de citocinas encefalitogênicas no SNC. Considerando que recentemente nosso grupo de pesquisa demonstrou que a vacinação com MOG associada à vitamina D (MOG+VitD) preveniu a encefalomielite, investigamos também se a infecção por C. albicans é capaz de quebrar a tolerância induzida por esta vacinação. Para isto, camundongos foram vacinados com MOG+VitD, infectados com C. albicans e depois submetidos à indução da EAE. A vacinação determinou proteção caracterizada por melhora significativa da sintomatologia, decréscimo acentuado na produção de citocinas encefalitogênicas no baço e no SNC e expansão de células T reguladoras. No seu conjunto os resultados desta investigação indicam que derivados fúngicos, dependendo de suas características, podem ser deletérios ou protetores no desenvolvimento da EAE.Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS). Data from patients and experimental models suggest that fungal infection and fungalderived antigens could contribute to the immunopathogenesis of this pathology. The main objective of this research was to investigate the effect of C. albicans and fungal derivatives on experimental autoimmune encephalomyelitis (EAE) that is a widely employed animal model to study MS. Initially, C57BL/6 mice were infected with C. albicans and three days later they were submitted to EAE induction. Infected animals developed a more severe disease associated with fungus spread to the CNS and increased production of encephalitogenic cytokines as TNF-α, IL-6, IL-17 and IFN-γ by cells from the spleen and the CNS. To test the effect of fungal derivatives mice were submitted to EAE induction and then injected with three doses of gliotoxin or dead yeasts of C. albicans. Gliotoxin inoculation resulted in clinical disease aggravation, higher local inflammatory infiltration and higher production of TNF-α by the CNS. Dead C. albicans inoculation determined a less severe disease associated with a lower production of encephalitogenic cytokines and a lower degree of apoptosis by CNS eluted cells. Lastly we demonstrated that C. albicans infection did not disrupt the prophylactic efficacy of MOG+VitD tolerogenic vaccination. Even in infected mice this vaccine decreased clinical signs, downmodulated the production of encephalitogenic cytokines and also increased the percentage of regulatory T cells. All together these results indicate that C. albicans infection and gliotoxin inoculation aggravate EAE development whereas dead C. albicans inoculation protected the animals.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Experimental Autoimmune Encephalomyelitis Is Successfully Controlled by Epicutaneous Administration of MOG Plus Vitamin D Analog

Multiple sclerosis (MS) is an inflammatory and demyelinating disorder of the central nervous system (CNS). Experimental autoimmune encephalomyelitis (EAE) has been widely employed to evaluate new strategies to control MS, including procedures to induce immunological tolerance. Considering that skin exposure to protein antigens can induce tolerance and that vitamin D analogs conserve immunomodulatory potential and are less toxic, we investigated the efficacy of epicutaneous application of a myelin oligodendrocyte glycoprotein peptide (MOG35–55) associated with paricalcitol (PARI) on EAE development. Three and 11 days after EAE induction, C57BL/6 mice were treated with an occlusive patch containing MOG plus PARI. Clinical parameters were daily assessed, whereas immunological and histological evaluations were performed during the acute EAE phase. MOG and MOG + PARI significantly controlled disease development reducing weight loss and clinical score. Moreover, MOG and MOG + PARI reduced the inflammatory process and preserved the myelin sheath in the CNS. High percentages of Foxp3+ regulatory T cells (Tregs) and lower MHCII fluorescence intensity in dendritic cells in draining lymph nodes were concomitantly observed. MOG + PARI association was, however, more efficient being able to reduce disease incidence and clinical scores more significantly than MOG or PARI alone. This experimental group also displayed a higher ratio between mRNA expression for Foxp3 and RORc and a higher percentage of Foxp3+ cells in the CNS. Modulation of activation markers observed in microglial cells eluted from EAE treated mice were confirmed by in vitro studies with the BV-2 microglial cell line. The results show that MOG + PARI association applied by an epicutaneous route controlled EAE development. Protective involved mechanisms include mainly a higher proportion of Tregs and also a direct immunomodulatory effect of PARI on microglial cells

Trafficking of phagocytic peritoneal cells in hypoinsulinemic-hyperglycemic mice with systemic candidiasis

Background: Candidemia is a severe fungal infection that primarily affects hospitalized and/or immunocompromised patients. Mononuclear phagocytes have been recognized as pivotal immune cells which act in the recognition of pathogens, phagocytosis, inflammation, polarization of adaptive immune response and tissue repair. Experimental studies have showed that the systemic candidiasis could be controlled by activated peritoneal macrophages. However, the mechanism to explain how these cells act in distant tissue during a systemic fungal infection is still to be elucidated. In the present study we investigate the in vivo trafficking of phagocytic peritoneal cells into infected organs in hypoinsulinemic-hyperglycemic (HH) mice with systemic candidiasis. Methods: The red fluorescent vital dye PKH-26 PCL was injected into the peritoneal cavity of Swiss mice 24 hours before the intravenous inoculation with Candida albicans. After 24 and 48 hours and 7 days of infection, samples of the spleen, liver, kidneys, brain and lungs were submitted to the microbiological evaluation as well as to phagocytic peritoneal cell trafficking analyses by fluorescence microscopy. Results: In the present study, PKH+ cells were observed in the peritoneum, kidney, spleen and liver samples from all groups. In infected mice, we also found PKH+ cells in the lung and brain. The HH condition did not affect this process. Conclusions: In the present study we have observed that peritoneal phagocytes migrate to tissues infected by C. albicans and the HH condition did not interfere in this process. © 2013 Fraga-Silva et al.; licensee BioMed Central Ltd

Systemic Administration of Proteoglycan Protects BALB/c Retired Breeder Mice from Experimental Arthritis

This study was undertaken to evaluate the prophylactic potential of proteoglycan (PG) administration in experimental arthritis. Female BALB/c retired breeder mice received two (2xPG50 and 2xPG100 groups) or three (3xPG50 group) intraperitoneal doses of bovine PG (50 μg or 100 μg) every three days. A week later the animals were submitted to arthritis induction by immunization with three i.p. doses of bovine PG associated with dimethyldioctadecylammonium bromide adjuvant at intervals of 21 days. Disease severity was daily assessed after the third dose by score evaluation. The 3xPG50 group showed significant reduction in prevalence and clinical scores. This protective effect was associated with lower production of IFN-γ and IL-17 and increased production of IL-5 and IL-10 by spleen cells restimulated in vitro with PG. Even though previous PG administration restrained dendritic cells maturation this procedure did not alter the frequency of regulatory Foxp3+ T cells. Lower TNF-α and IL-6 levels and higher expression of ROR-γ and GATA-3 were detected in the paws of protected animals. A delayed-type hypersensitivity reaction confirmed specific tolerance induction. Taken together, these results indicate that previous PG inoculation determines a specific tolerogenic effect that is able to decrease severity of subsequently induced arthritis

Treatment with Vitamin D/MOG Association Suppresses Experimental Autoimmune Encephalomyelitis

<div><p>Experimental autoimmune encephalomyelitis (EAE) is an animal model to study multiple sclerosis (MS). Considering the tolerogenic effects of active vitamin D, we evaluated the therapeutic effect of myelin oligodendrocyte glycoprotein (MOG) associated with active vitamin D in EAE development. EAE was induced in female C57BL/6 mice by immunization with MOG emulsified with Complete Freund’s Adjuvant plus <i>Mycobacterium tuberculosis</i>. Animals also received two intraperitoneal doses of <i>Bordetella pertussis</i> toxin. One day after immunization, mice were treated with 0,1μg of 1α,25-dihydroxyvitamin D3 (1,25(OH)₂D₃) every other day during 15 days (on days 1, 3, 5, 7, 9, 11, 13 and 15). MOG (150μg) was co-administered on days 3 and 11. The administration of 1,25(OH) ₂D₃ or MOG determined significant reduction in EAE incidence and in clinical scores. When MOG was associated with 1,25(OH) ₂D₃ the animals did not develop EAE. Spleen and central nervous system (CNS) cell cultures from this group produced less IL-6 and IL-17 upon stimulation with MOG in comparison to the EAE control group. In addition, this treatment inhibited dendritic cells maturation in the spleen and reduced inflammatory infiltration in the CNS. The association of MOG with 1,25(OH) ₂D₃ was able to control EAE development.</p></div

Candida tropicalis Systemic Infection Redirects Leukocyte Infiltration to the Kidneys Attenuating Encephalomyelitis

Environmental factors, including infections, are strongly associated with the pathogenesis of multiple sclerosis (MS), which is an autoimmune and demyelinating disease of the central nervous system (CNS). Although classically associated with bacterial and viral agents, fungal species have also been suspected to affect the course of the disease. Candida tropicalis is an opportunistic fungus that affects immunocompromised individuals and is also able to spread to vital organs. As C. tropicalis has been increasingly isolated from systemic infections, we aimed to evaluate the effect of this fungus on experimental autoimmune encephalomyelitis (EAE), a murine model to study MS. For this, EAE was induced in female C57BL/6 mice 3 days after infection with 106 viable C. tropicalis yeasts. The infection decreased EAE prevalence and severity, confirmed by the less inflammatory infiltrate and less demyelization in the lumbar spinal cord. Despite this, C. tropicalis infection associated with EAE results in the death of some animals and increased urea and creatinine serum levels. The kidneys of EAE-infected mice showed higher fungal load associated with increased leukocyte infiltration (CD45+ cells) and higher expression of T-box transcription factor (Tbx21) and forkhead box P3 (Foxp3). Altogether, our results demonstrate that although C. tropicalis infection reduces the prevalence and severity of EAE, partially due to the sequestration of leukocytes by the inflamed renal tissue, this effect is associated with a poor disease outcome

Effect of treatment with 1,25(OH)₂D₃+MOG association on EAE development.

<p>Kinetics of clinical scores (<b>A</b>), maximum clinical score (<b>B</b>) and weight variation (<b>C</b>). Comparisons between groups were made by one way ANOVA followed by Tukey’s test for parametric variables (<b>A</b> and <b>C</b>) and by Kruskal-Wallis followed by Dunn’s test for non-parametric variables (<b>B</b>). Results were expressed as mean or medians (25–75% ranges) of 12 animals per group. * p<0.05 compared with EAE+MOG, EAE+vitD and EAE/vitD+MOG groups. Data are representative of two independent experiments.</p