Hydroxychloroquine decreases Th17-related cytokines in systemic lupus erythematosus and rheumatoid arthritis patients

OBJECTIVES: Hydroxychloroquine is an antimalarial agent that has been used in systemic lupus erythematosus and rheumatoid arthritis treatment for many years. Recently, novel mechanisms of action have been proposed, thereby broadening the therapeutic perspective of this medication. The purpose of this study was to evaluate the immunomodulatory activity of hydroxychloroquine in T helper 17 (Th17) cytokines in healthy individuals and patients. METHODS: Eighteen female patients with systemic lupus erythematosus (mean age 39.0±12.9 years) and 13 female patients with rheumatoid arthritis (mean age 51.5±7.7 years) were recruited from Universidade Federal de Pernambuco-Brazil. The patients were included after fulfilling four classification criteria for systemic lupus erythematosus or rheumatoid arthritis from the American College of Rheumatology. After being stimulated with phorbol 12-myristate 13-acetate and ionomycin in the absence or presence of different concentrations of hydroxychloroquine, the interleukin 6, 17 and 22 levels were quantified with an enzyme-linked immunosorbent assay in culture supernatants of peripheral blood mononuclear cells from healthy individuals and patients. RESULTS: We demonstrated that in peripheral blood mononuclear cells from healthy volunteers and in systemic lupus erythematosus and rheumatoid arthritis patients, there was a significant reduction in the IL-6, IL-17 and IL-22 supernatant levels after adding hydroxychloroquine. CONCLUSIONS Our in vitro results demonstrated that hydroxychloroquine inhibits IL-6, IL-17 and IL-22 production and contributes to a better understanding of the mechanism of action of this medication

Synthesis and biological evaluation of novel imidazolidine derivatives as candidates to schistosomicidal agents

Introduction: Schistosomiasis is an infectious parasitic disease caused by trematodes of the genus Schistosoma, which threatens at least 258 million people worldwide and its control is dependent on a single drug, praziquantel. The aim of this study was to evaluate the anti-Schistosoma mansoni activity in vitro of novel imidazolidine derivatives. Material and methods: We synthesized two novel imidazolidine derivatives: (LPSF/PTS10) (Z)-1-(2-chloro-6-fluorobenzyl)-4-(4-dimethylaminobenzylidene)-5-thioxoimidazolidin-2-one and (LPSF/PTS23) (Z)-1-(2-chloro-6-fluoro-benzyl)-5-thioxo-4-(2,4,6-trimethoxy-benzylidene)-imidazolidin-2-one. The structures of two compounds were determined by spectroscopic methods. During the biological assays, parameters such as motility, oviposition, mortality and analysis by Scanning Electron Microscopy were performed. Results: LPSF/PTS10 and LPSF/PTS23 were considered to be active in the separation of coupled pairs, mortality and to decrease the motor activity. In addition, LPSF/PTS23 induced ultrastructural alterations in worms, after 24 h of contact, causing extensive erosion over the entire body of the worms. Conclusion: The imidazolidine derivatives containing the trimetoxy and benzylidene halogens showed promising in vitro schistosomicidal activity

Novas 2-tioxo-imidazolidin-4-onas candidatas a fármacos esquistossomicidas : síntese, elucidação estrutural e atividade biológica

A esquistossomose, helmintíase largamente disseminada em todo o mundo, é causada por espécies do gênero Schistosoma. Segundo relatos da WHO, cerca de 200.000 pessoas morrem anualmente vítimas desta parasitose. A quimioterapia representa atualmente o maior instrumento para seu controle. Devido à ocorrência de isolados de Schistosoma mansoni resistentes ao único fármaco disponível, o praziquantel, o objetivo desse trabalho foi a busca de novos candidatos a fármacos esquistossomicidas através da síntese de novas 1-metil-2-tioxoimidazolidin- 4-onas: 3-benzil-5-(3-flúor-benzilideno)-1-metil-2-tioxo-imidazolidin-4- ona (JT-53), 3-benzil-1-metil-5-(4-metil-benzilideno)-2-tioxo-imidazolidin-4-ona (JT- 63), 3-benzil-1-metil-5-(4-metoxi-benzilideno)-2-tioxo-imidazolidin-4-ona (JT-68), 3- (4-cloro-benzil)-1-metil-5-(4-metoxi-benzilideno)-2-tioxo-imidazolidin-4-ona (JT-69) e 3-bifenil-4-ilmetil-1-metil-5-(4-metoxi-benzilideno)-2-tioxo-imidazolidin-4-ona (JT- 72) e também a avaliação da susceptibilidade in vitro do S. mansoni. Os compostos foram obtidos pela reação da 1-metil-2-tioxo-imidazolidin-4-ona com os ésteres de Cope em presença de piperidina, conduzindo aos derivados 5- benzilideno-1-metil-2-tioxo-imidazolidin-4-onas (HT). Estes reagiram com brometo de benzila substituído ou não, levando aos derivados imidazolidínicos (JT), os quais foram devidamente caracterizados por métodos convencionais de análise. Vermes adultos de S. mansoni mantidos em placas contendo meio de cultura apropriado foram submetidos às novas imidazolidinas nas concentrações de 80,5; 161,0; 322,0 e 644,0 μM. A viabilidade dos vermes foi observada a cada 24 horas durante 8 dias, em microscópio invertido. Os resultados obtidos demonstraram que os parasitas foram sensíveis às substâncias nas concentrações indicadas, apresentando, além de elevados índices de mortalidade, modificações da atividade motora e alterações significativas no tegumento, ocasionando perda de sua integridade. Os resultados indicaram que as novas 1-metil-2-tioxoimidazolidin- 4-onas provocaram efeitos biológicos deletérios e irreversíveis em vermes adultos de S. mansoni e que a resposta biológica segue uma relação dose-dependent

Etude de la voie TH17 dans les leishmanioses

Les infections humaines par les protozoaires du genre Leishmania peuvent être asymptomatiques ou provoquer des pathologies cutanées et viscérales graves conduisant dans certains cas au décès du patient. Ces maladies sont endémiques dans 88 pays du monde et l on considère qu elles menacent 350 millions de personnes. Mon travail de thèse a tout d abord permis de démontrer que les parasites Leishmania donovani et Leishmania braziliensis, qui provoquent respectivement la leishmaniose viscérale (LV ou KA) et la leishmaniose cutanée (LC), sont de forts inducteurs de la production d IL-17, d IL-22 et d IFN-g par les lymphocytes des patients sains. Une analyse phénotypique montre que ceux sont les lymphocytes T CD4+ qui produisent l IL-17. Par la suite, au cours d une épidémie de KA au Soudan, nous avons détecté de l IL-17, de l IL-22 et de l IFN-g dans la plupart des cultures de PBMC provenant de 87 patients résistants à l infection, et seulement dans un faible nombre de cultures provenant de 122 patients qui ont eu un épisode récent de KA. Une analyse multivariée de la production d IFN-g, du TNF, d IL-12p40, d IL-4, d IL-13, d IL-6, d IL-10, d IL-1b, d IL-17 et d IL-22 dans les cultures a montré que l IL-17 et l IL-22 sont les cytokines les plus fortement associées avec la résistance au KA. Parallèlement, une faible production d IL-17 après stimulation par les antigènes de L. donovani s avère prédictive du KA. L analyse des cytokines régulatrices de la voie Th17, c est-à-dire l IL-23, l IL-1b et l IL-6, indique que la production de ces cytokines est altérée chez les patients ayant un KA. Nous avons également réalisé une étude similaire dans une région endémique à L. braziliensis au Brésil, celle-ci suggère que l IL-17 et l IL-22 sont produites davantage chez les patients ayant guéri d une leishmaniose cutanée, par comparaison aux patients porteur d une lésion active. Cependant ces résultats n ont pas été confirmés dans une deuxième étude qui est en cours. Ces données sont la première démonstration chez l homme de l induction par Leishmania des lymphocytes CD4+IL-17+ (Th17). Elles apportent également les premières indications d un rôle protecteur de l IL-17 et l IL-22 dans une infection chez l homme.The human infections by the parasitic protozoa of the genus Leishmania can be asymptomatic or can cause serious cutaneous and visceral pathologies that can lead to the death of the patient. These diseases are endemic in 88 countries around the world and 350 millions of people are at risk of infection. We showed that the parasites Leishmania donovani and Leishmania brazilienses, which leads to visceral leishmaniasis (VL or KA) and cutaneous leishmaniasis (CL) respectively, are strong inducer of the production of IL-17, IL-22 and IFN-g by PBMC from healthy patients. Phenotype analysis then showed that IL-17 is produced by lymphocytes T CD4+. Also, during a KA outbreak in Sudan, we detected the production of IL-17, IL-22 and IFN-g in most cultures of PBMC coming from 87 patients resistant to the infection, and only in a few number of cultures coming from 122 patients that had a recent episode of KA. Multivariate analysis of the production of IFN-g, TNF, IL-12p40, IL-4, IL-13, IL-6, IL-10, IL-1b, IL-17 and IL-22 in cultures showed that IL-17 and IL-22 are the most strongly associated cytokines with the resistance to KA. Furthermore, the low IL-17 production was predictive of KA. The analysis of regulatory cytokines of the Th17 axis: IL-23, IL-1b and IL-6, indicates that the production of these cytokines are deficient in patients that had a recent episode of KA. In another study accomplished in an endemic region of L. braziliensis in Brazil, we showed that IL-17 and IL-22 are strongly produced in healed patients compared to patients who have an active lesion of the disease. However a second study does not seem to confirm these results. Our results are the first demonstration of the induction of the lymphocytes CD4+IL-17+ (Th17) pathway in human by the parasite Leishmania and the first strong indication that IL-17 and IL-22 can play a crucial role in the resistance against the infection.AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocSudocFranceF

PPARγ Agonists in Adaptive Immunity: What Do Immune Disorders and Their Models Have to Tell Us?

Adaptive immunity has evolved as a very powerful and highly specialized tool of host defense. Its classical protagonists are lymphocytes of the T- and B-cell lineage. Cytokines and chemokines play a key role as effector mechanisms of the adaptive immunity. Some autoimmune and inflammatory diseases are caused by disturbance of the adaptive immune system. Recent advances in understanding the pathogenesis of autoimmune diseases have led to research on new molecular and therapeutic targets. PPARγ are members of the nuclear receptor superfamily and are transcription factors involved in lipid metabolism as well as innate and adaptive immunity. PPARγ is activated by synthetic and endogenous ligands. Previous studies have shown that PPAR agonists regulate T-cell survival, activation and T helper cell differentiation into effector subsets: Th1, Th2, Th17, and Tregs. PPARγ has also been associated with B cells. The present review addresses these issues by placing PPARγ agonists in the context of adaptive immune responses and the relation of the activation of these receptors with the expression of cytokines involved in adaptive immunity

The Japanese Health System and its coping mechanisms against COVID-19

Introdução: apesar de ser o país de maior média de idade no mundo, o Japão tem se destacado no combate à pandemia da COVID-19 (do inglês Coronavirus Disease 2019) ao apresentar reduzidas taxas de contaminação pelo vírus e de mortalidade. Objetivo: discutir acerca das estratégias em saúde adotadas pelo Japão diante da pandemia da doença da COVID-19, bem como avaliar os dados sobre contaminação e mortalidade japoneses em comparação com os outros quatro países com maior média de idade do mundo (Itália, Alemanha, Portugal e Espanha) e o Brasil. Metodologia: para avaliação das estratégias em saúde japonesas foi realizada busca nas bases de dados: PubMed, Cochrane e Scielo, utilizando-se combinação dos termos “Japão”, “covid”, “coronavirus” e “sistemas de saúde”, nos idiomas Inglês, Espanhol e Português. Os dados de infecção da COVID-19 foram extraídos do site Our World in Data, correspondendo ao período de 25 de janeiro de 2020 a 30 de julho de 2020. Resultados: dentre as medidas adotadas pelo país no enfrentamento à pandemia, destacam-se o diagnóstico e resposta precoces à infecção, o rastreamento de contatos, o diagnóstico precoce e disponibilidade de cuidados intensivos para pacientes graves e estímulo a medidas comportamentais de distanciamento. Dentre os países analisados, o Japão apresenta as menores taxas de contaminação e mortalidade em termos absolutos pela COVID-19. Conclusões: medidas de distanciamento social, diagnóstico e tratamento precoces parecem ter contribuído para o sucesso no combate à COVID-19 no Japão. No período estudado, em milhão de habitantes, o Japão teve 6,13 casos de Covid, enquanto o Brasil apresentou 218,26 casos. Já no número de mortes confirmadas pela doença, o primeiro teve uma taxa de 0,23 enquanto o segundo de 5,16 casos por milhão de habitantes. É possível, a partir do conhecimento dessas medidas, buscar mecanismos semelhantes ao traçar políticas de saúde no enfrentamento de pandemias em outros países.Introduction: despite being the country with the highest average age globally, Japan has stood out in the fight against the COVID-19 (Coronavirus Disease 2019) pandemic by presenting low contamination rates by the virus and mortality. Objective: we aim to discuss the health strategies adopted by Japan in the face of the COVID-19 disease pandemic, as well as to evaluate data on Japanese contamination and mortality compared to the other four countries with the highest average age in the world (Italy, Germany, Portugal and Spain) and Brazil. Methodology: the search was carried out to evaluate Japanese health strategies by using the following databases: PubMed, Cochrane, and Scielo using a combination of the terms "Japan", "covid", "coronavirus" and "health systems" in English, Spanish and Portuguese. The COVID-19 infection data was extracted from the Our World in Data website, from January 25, 2020, to July 30, 2020. Results: Among the measures adopted by the country to face the pandemic, the early diagnosis and response to infection, contact tracing, early diagnosis and availability of intensive care for critically ill patients, and encouraging behavioral distancing measures stand out. Among the countries analyzed, Japan has the lowest rates of contamination and mortality in absolute terms by COVID-19. Conclusions: social distancing measures, early diagnosis, and treatment seem to have contributed to the success in combating COVID-19 in Japan. In the studied period, in a million inhabitants, Japan had 6.13 cases of covid while Brazil had 218.26 cases. As for the number of deaths confirmed by the disease, the first had a rate of 0.23 while the second had 5.16 cases per million inhabitants. Based on the knowledge of these measures, it is possible to seek similar mechanisms when designing health policies to face pandemics in other countries

Synthesis of a Novel Thiazolidinedione and Evaluation of Its Modulatory Effect on IFN-γ, IL-6, IL-17A, and IL-22 Production in PBMCs from Rheumatoid Arthritis Patients

Rheumatoid arthritis (RA) is an autoimmune disease frequently characterized by chronic synovitis of multiple joints. The pathogenesis of RA is complex and involves many proinflammatory cytokines as Th17 related ones. PPARγ is a nuclear receptor activator that represses proinflammatory gene expression. Thus, this work aimed to synthetize a new thiazolidinedione (TZD) analogue based on a well-known anti-inflammatory and PPARγ agonist activity of this ring and evaluate its anti-inflammatory activity. After chemical structure confirmation, the compound named 5-(5-bromo-2-methoxy-benzylidene)-3-(2-nitro-benzyl)-thiazolidine-2,4-dione TM17 was submitted to cytokine releasing inhibition and PPARγ genetic modulation assays. The new compound showed no toxicity on human and murine cells, decreasing IL-6 secretion by murine splenocytes and reducing IL-17A, IL-22, and IFN-γ expression in peripheral blood mononuclear cells from patients with RA. TM17 was more efficient in modulating the mRNA expression of PPARγ than its well-used TZD agonist rosiglitazone. Surprisingly, TM17 was efficient on IL-17A and IFN-γ reduction, like the positive control methylprednisolone, and presented a better effect on IL-22 levels. In conclusion, PBMCs obtained from RA patients under TM17 treatment present a significant reduction in IL-17A, IL-22, and IFN-γ levels, but not IL-6 when compared with nontreated cells, as well as increase PPARγ mRNA expression in absence of stimulus addressing it as a promising molecule in RA treatment

Galectin-9 gene (LGALS9) polymorphisms are associated with rheumatoid arthritis in Brazilian patients.

IntroductionRheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation and hyperplasia, as well as cartilage and bone destruction. Several proteins are associated with the pathogenesis of the disease. Galectin-9 belongs to the family of lectins that are involved in various biological processes and have anti-inflammatory activity.ObjectiveTo investigate associations between the SNPs of the GAL-9 gene (LGALS9) and serum levels in rheumatoid arthritis patients. We extracted DNA from 356 subjects, 156 RA patients and 200 healthy controls from northeastern Brazil. Three polymorphisms (rs4795835, rs3763959, and rs4239242) in the LGALS9 gene were selected and genotyped using TaqMan SNP genotyping assay. Serum concentrations of galectin-9 were analyzed by ELISA.ResultsThe rs4239242 TT genotype showed a positive association with RA (p = 0.0032, odds ratio = 0.28), and heterozygous TC were prevalent in the control group compared to RA patients (p = 0.0001, odds ratio = 7.99). Galectin-9 serum levels were significantly increased in RA patients compared to the control group (p<0.0001). Patients in remission had high levels of galectin compared to the moderate activity group (p<0.0001). Regarding the Clinical Disease Activity Index (CDAI), patients in remission or low activity presented high levels of galectin when compared to patients in severity (p<0.0001). Patients performing moderate activity had a significant value compared to patients who were in high disease severity (p = 0.0064). Interestingly, the AG genotype (rs3763959) has been associated with a higher presence of bone erosion in RA patients (p = 0.0436). The SNP rs4239242 TT genotype showed a positive association with RA in comparison to the control group. The AG genotype (rs3763959) has been associated with a higher presence of bone erosion in RA patients