Submitted by PPG Biologia Celular e Molecular (bcm@pucrs.br) on 2018-04-17T11:55:36Z No. of bitstreams: 1 LAURA_ESTEVES_PETERSEN_TES.pdf: 11032751 bytes, checksum: 519545881a34767f1600d5189b0ddc8e (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-05-04T17:09:09Z (GMT) No. of bitstreams: 1 LAURA_ESTEVES_PETERSEN_TES.pdf: 11032751 bytes, checksum: 519545881a34767f1600d5189b0ddc8e (MD5) / Made available in DSpace on 2018-05-04T17:15:58Z (GMT). No. of bitstreams: 1 LAURA_ESTEVES_PETERSEN_TES.pdf: 11032751 bytes, checksum: 519545881a34767f1600d5189b0ddc8e (MD5) Previous issue date: 2018-03-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Rheumatoid Arthritis (RA) is an autoimmune and inflammatory disease which leads to premature immunosenescence and the development of articular and extra-articular manifestations, including joint damage and cognitive dysfunction, respectively. Peripheral immune system cells and the chronic inflammation, both of great importance for RA, are potentials mechanisms involved in cognitive dysfunction. In contrast, experimental studies have shown the beneficial contribution of immune cells, mainly T cells reactive to central nervous system (CNS) antigens, to neurogenesis and neuroplasticity. Previous data have shown that RA patients besides to have worse performance in cognitive tests, have significantly lower levels of B cells and higher levels of senescent T cells (CD8+CD28-). However, is not known yet which B cells subpopulations are related to poor cognitive performance, if clinical severity of disease (active and controlled disease) impacts on cognition and which factor is responsible for remodeling of peripheral immunity (immunosenescence). Hypotheses about the contribution of latent infections (Cytomegalovirus; CMV), for the development of immunosenescence (observed by telomere shortening and increase of CD28- cells) have been raised. However, it remains in discussion the CMV soroprevalence and its relation with the development of premature immunological senesce in RA. Based on this findings, in this work we have broadly assessment the cognition of RA patients with active and controlled disease, peripheral levels of lymphocytes subsets (T and B cells), neurotrophic factors, cytokines besides that CMV soroprevalence and immunosenescence profile (telomere length and CD28- cells). This work also proposed to explore the relationship between immune mediators, neurotrophic factors and cognitive performance, besides the association between CMV and immunosenescence. For this purpose, 102 RA patients (67 active and 35 controlled disease) and 30 healthy controls adjusted for age, gender and schooling were recruited. The cognitive function, levels of stress and depression were assessment by means of neurocognitive tests (Mini Mental State Examination, Logical memory, digit span, Trail Making Test, N-back, Stroop word-colors) and specific questionnaires (Beck Depression Inventory ?II for depression and Perceived Stress Scale for stress). Twenty ml of blood were collected and, after plasma separation, the peripheral blood mononuclear cells (PBMCs) were isolated by centrifugation gradient. PBMCs were immunophenotyped by flow cytometry to investigate the frequency of T and B cells subsets. The genomic DNA was isolated from PBMCs and the telomere length was evaluated by real time PCR. Neurotrophic factors, cytokines, IgM and IgG anti-CMV were measured in plasma by means of ELISA (NF and CMV) and Citometric Bead Array (CBA; cytokines). In general, patients with active disease had worse cognitive performance, followed by patients with controlled disease producing cells, in addition to high levels of cytokines, with the exception of IL-17A. Higher levels of BDNF were found in patients with active RA followed by controlled disease and control group. The peripheral levels of GDNF were lower in patients with active RA than control group. The IL-6 was predictor of the performance in Trail Making test. IgM and IgG anti-CMV antibody titers did not differ between patients and controls. Only IgG anti-CMV was positively associated with age and senescent cells. In conclusion, RA patients with active disease had worse performance in cognitive tasks that were related to peripheral immune mediators (cells and cytokines). Besides that, we found that late infection (IgG) by CMV were associated only with CD4+CD27-CD28- and haven?t correlated with other immunosenescence characteristics. However, understand in which sense e how the relationship between the peripheral environment and the CNS is established, may contribute to development of preventive interventions to cognitive impairments and premature immunosenescence, since both factors are associated to health and well-being of individuals. / A artrite reumatoide (AR) ? uma doen?a autoimune inflamat?ria que leva ? imunossenesc?ncia prematura e ao desenvolvimento de manifesta??es articulares e extraarticulares, entre elas a destrui??o da articula??o e o decl?nio cognitivo, respectivamente. C?lulas do sistema imune perif?rico e a inflama??o cr?nica, ambos de grande import?ncia para a AR, s?o potenciais mecanismos envolvidos na disfun??o cognitiva. Em contrapartida, estudos experimentais tem revelado a contribui??o ben?fica das c?lulas imunol?gicas, principalmente c?lulas T reativas a ant?genos do sistema nervoso central (SNC), para a neurog?nese e neuroplasticidade. Dados pr?vios apontam que pacientes com AR al?m de apresentarem piores desempenhos nos testes cognitivos, tem significativamente menos c?lulas B e mais c?lulas T com perfil senescente (CD8+CD28-). Entretanto ainda n?o se sabe quais subpopula??es de c?lulas B est?o relacionadas ao pior desempenho cognitivo, se a severidade cl?nica da doen?a (doen?a ativa e controlada) impacta sobre a cogni??o e qual fator seria respons?vel pelo remodelamento da imunidade perif?rica (imunossenesc?ncia). Hip?teses sobre a contribui??o de infec??es latentes, como a causada pelo citomegalov?rus (CMV), para o desenvolvimento da imunossenesc?ncia, observada pelo encurtamento telom?rico e aumento na frequ?ncia de c?lulas CD28-, tem sido levantadas. Por?m, permanece em discuss?o a soropreval?ncia da infec??o pelo CMV e sua real rela??o com o desenvolvimento da senesc?ncia imunol?gica prematura na AR. Com base nestas constata??es, nesta tese n?s avaliamos amplamente a cogni??o de pacientes com AR ativa e controlada, n?veis perif?ricos de subtipos linfocit?rios (c?lulas T e B), fatores neurotr?ficos (FN), citocinas, al?m da soropositividade para CMV e perfil de imunossenesc?ncia prematura (encurtamento telom?rico e aumento de c?lulas CD28-). Esta tese tamb?m se prop?s explorar a rela??o entre mediadores imunes, FN e desempenho cognitivo, e a associa??o entre CMV e caracter?sticas de imunossenesc?ncia. Para esta finalidade, 102 pacientes com AR (67 com doen?a ativa e 35 com doen?a controlada) e 30 controles saud?veis ajustados para idade, g?nero e escolaridade foram recrutados. A fun??o cognitiva, n?veis de estresse e depress?o foram avaliados por meio de testes neurocognitivos (Mini Exame do Estado Mental, Mem?ria L?gica, Subteste de D?gitos, Trail Making Test, N-back, Stroop palavras-cores) e question?rios espec?ficos (Beck Depression Inventory ?II e Escala de Estresse Percebido). Foram coletados 20 ml de sangue e, ap?s a separa??o do plasma, as c?lulas mononucleares do sangue perif?rico (PBMCs) foram isoladas por gradiente de centrifuga??o. PBMCs foram imunofenotipadas por citometria de fluxo para investigar a frequ?ncia de subpopula??es de c?lulas T e B. FN, citocinas, IgM e IgG anti-CMV foram dosados no plasma atrav?s da t?cnica de ELISA (FN e CMV) e Citometric Bead Array (CBA; citocinas). De forma geral, pacientes com doen?a ativa tiveram o pior desempenho nos testes cognitivos, seguido pelos indiv?duos com doen?a controlada e grupo controle. Pacientes com AR tiveram elevados n?veis perif?ricos de c?lulas B imaturas e produtoras de anticorpos, al?m de elevados n?veis das citocinas, com exce??o da IL-17. Maiores concentra??es de BDNF foram observadas nos indiv?duos com AR ativa, seguido pelo grupo controlado e controle. Os n?veis perif?ricos de GDNF foram menores em pacientes com AR ativa do que em indiv?duos controle. A IL-6 apresentou-se como preditora do desempenho do Trail Making Test. T?tulos dos anticorpos IgM e IgG anti-CMV n?o diferiram entre pacientes e controles. Somente o IgG anti-CMV foi relacionado positivamente com idade e c?lulas senescentes. Concluindo, pacientes com AR ativa apresentam pior desempenho em tarefas cognitivas as quais est?o relacionadas a mediadores imunes perif?ricos. Al?m disso, observou-se que infec??es tardias pelo CMV (t?tulos de anticorpos IgG anti-CMV) foram somente associadas a c?lulas T senescentes e n?o se correlacionaram com outras caracter?sticas da imunossenesc?ncia. Portanto, compreender em qual sentido e como a rela??o entre o ambiente perif?rico e do SNC se estabelece, pode contribuir para o desenvolvimento de interven??es preventivas ao d?ficit cognitivo e senesc?ncia prematura, uma vez que ambos fatores est?o associados a sa?de e o bem ? estar dos indiv?duos.