Figure 1: Sleep loss promotes a low-grade proinflammatory status. Sleep loss is characterized by an increase in circulating proinflammatory cytokines (IL-1β, IL-6, IL-17A, TNF-α) and CRP. Image shows the differential effect of sleep loss on the immune system after acute total sleep deprivation and prolonged sleep restriction and or sleep fragmentation. The acute and chronic events of sleep loss correlate with the temporal immune response (innate and adaptive). Prolonged sleep loss plus insufficient sleep recovery are considered an important risk factor to develop metabolic, cardiovascular, and neurodegenerative diseases related with the deregulation of the neuro-endocrine-immune network. Abbreviations: APCs; antigen-presenting cells; CRP, C-reactive protein; CVD, cardiovascular disease; N, neurodegenerative diseases; NK, natural killer; SR, sleep restriction; SF, sleep fragmentation; TSD, total sleep deprivation.