Cytokines Role in the Regulation of Sleep

Although sleep deprivation studies and insomnia studies both indicate that inflammatory cytokines are elevated subsequent to sleep loss, cytokines themselves appear to impact sleep. Animal studies indicate that administration of inflammatory cytokines have varying effects on sleep, depending on the nature, timing, and dose of cytokine administered. IL-6 has been described as a sleep modulator and its administration produces sleep fragmentation in rats (Hogan et al. 2003). IL-1 and TNF produce...

Chronic Inflammatory Diseases and Sleep

Sleep disorders are frequently observed in chronic inflammatory diseases. Such disorders are believed to be an intrinsic component of the disease and not simply a consequence of the pain. Nonetheless, fatigue, pain, and muscle rigidity are associated to nonrestorative sleep (Nicassio, Moxham, Schuman, and Gevirtz 2002). What seems to take place is a vicious cycle in which pain and chronic fatigue leads to nonrestorative sleep, which in turn, worsens painful conditions. Among the chronic...

References

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Sickness Behavior Includes Changes in Circadian Rhythms

Circadian neuroimmune connections imply a very important feedback component provided by the immune cells to the brain. Indeed, there are several mechanisms by which the immune system can modify central clock structures (Dantzer 2001 Johnson 2002 Larson 2002). Peripheral inflammation results in production of cytokines, which can signal the SCN. In the case of rheumatoid arthritis, inflammation is characterized by increased local synovial and systemic levels of the proinflammatory cytokines IL-1,...

Melatonin as a Circadian Immunoregulatory Signal in Adjuvant Arthritis

Pineal melatonin is normally synthesized and secreted during the dark phase of the day in all species studied to date. The primary physiological function of melatonin is to convey information about daily cycles of light and darkness to body physiology. By its pattern of secretion during darkness, melatonin indicates the length of the scotophase, thus representing the chemical code of the night. This information is used for the organization of functions, which respond to changes in photoperiod...

Sleep and Cytokines in Rheumatoid Arthritis

The prevalence of sleep disturbance can be quite high in autoimmune disorders for example, 50 of multiple sclerosis patients report clinically relevant sleep complaints (Fleming and Pollak 2005) as do 61 of systemic lupus patients (Tench, McCurdie, White, and D'Cruz 2000). Perhaps the highest prevalence is in rheumatoid arthritis (RA) patients, between 50 and 75 of patients complain of difficulties initiating or maintaining sleep (Drewes 1999). Fatigue is a debilitating symptom in each of these...

The Rat Adjuvant Arthritis Is an Experimental Model of Rheumatoid Arthritis

Rheumatoid arthritis is a systemic inflammatory disorder that mainly affects the diarthrodial joint. It is the most common form of inflammatory arthritis and affects about 1 of the population, in a female male ratio of 2.5 1. The disease can occur at any age, but it is most common among those aged 40 to 70 years. The geographic distribution of rheumatoid arthritis is worldwide, with a notably low prevalence in rural areas Goodson and Symmons 2002 Reginster 2002 . Although it initially presents...