Doença de Parkinson: há associação entre dor e resposta imunologica?

Abstract

Non-motor symptoms of Parkinson´s Disease (PD) include autonomic alterations, cognitive and affective dysfunctions, sleep disturbances, fatigue, and pain. Immunological response plays a crucial role in both PD and pain conditions. The aim of this study was to evaluate expression ofcytokines in peripheral blood leukocytes of PD patients in order to determine if the presence of pain is associated to a specific immunological profile. Sixteen PD patients (8 with pain and 8without pain) were recruited and evaluated for signs and symptoms, cognitive function, depression, fatigue, sleep disturbances, and pain, if present. Blood was collected for flow cytometry immunophenotyping with markers for CD4, CD8, HLA-DR, TNF, IL-6, and IL-10. No difference regarding demographic and clinical data was observed between with pain and nopain groups. Greater intensities of pain were associated with more severe disease and mood and cognitive impairment. Immunological analysis did not show differences in expression of HLADR, TNF, IL-6, and IL-10 in monocytes, lymphocytes or CD4+ T cell population between groups. However, with pain group showed lower expression of evaluated molecules in total leucocyte population and of IL-6 in neutrophils. With pain group CD8+ T cell population hadgreater expression of TNF. IL-6/IL-10 and TNF/IL-10 ratios in PD patients with pain were lower in CD4+ T cell populations and greater in CD8+ T cell population, respectively, in comparison to no-pain group. Although it was not possible to establish an specific immunological profile for PDpatients with pain, our data showed an altered immune response in this group. Further studies with greater population and broader immunological analysis are desirable to establish or not if pain in PD leads to a specific profile of immune activation or regulation.