Neuropeptide Y plasma levels and immunological changes during academic stress

Academic stress is a good model of psychological stress in humans for studying psychoneuroimmune correlations. We looked for correlations between psychological scores, immune tests and plasma levels of cortisol and neuropeptide Y (NPY). A group of medical students were evaluated at the beginning of the academic year (Baseline) and the day before an examination (Stress). They underwent evaluation by The Profile of Mood States (POMS), The Malaise Inventory, The Self Efficacy Scale and A Global Assessment of Recent Stress (GARS). The lymphocyte subsets, the lymphocyte proliferative response and the cytokine production were also evaluated. We detected modifications of some psychological test scores between the Baseline and Stress evaluation, a significant reduction of lymphocyte proliferation, IL-2 production and percentage of the lymphocyte CD19, and an increase in plasma cortisol levels during stress. The lymphocyte proliferation negatively correlated with the POMS score as well as the percentage of CD16+ cells with NPY plasma levels. NPY levels were not different from Baseline. The emotional and mood states seem to influence immunity.