Effects of sleep deprivation on neural functioning: an integrative review

Sleep deprivation has a broad variety of effects on human performance and neural functioning that manifest themselves at different levels of description. On a macroscopic level, sleep deprivation mainly affects executive functions, especially in novel tasks. Macroscopic and mesoscopic effects of sleep deprivation on brain activity include reduced cortical responsiveness to incoming stimuli, reflecting reduced attention. On a microscopic level, sleep deprivation is associated with increased levels of adenosine, a neuromodulator that has a general inhibitory effect on neural activity. The inhibition of cholinergic nuclei appears particularly relevant, as the associated decrease in cortical acetylcholine seems to cause effects of sleep deprivation on macroscopic brain activity. In general, however, the relationships between the neural effects of sleep deprivation across observation scales are poorly understood and uncovering these relationships should be a primary target in future research

The role of complement activation in tumour necrosis factor-induced lethal hepatitis.

Injection of tumour necrosis factor (TNF) in animals causes severe liver cell toxicity, especially when D-(+)-galactosamine (GalN) is co-administered. After challenge with TNF/GalN, serum complement activity (CH50 and APCH50) decreased dramatically, suggesting strong activation of both the classical and the alternative pathways. TNF or GalN alone had no such effect. A cleavage product of complement protein C3 [C3(b)] was deposited on the surface of hepatocytes of TNF/GalN-treated mice. Intravenous administration of cobra venom factor (CVF), which depletes complement, inhibited the development of hepatitis. However, CVF pretreatment also protected C3-deficient mice. Pretreatment of mice with a C1q-depleting antibody did not prevent TNF/GalN lethality, although the anti-C1q antibody had depleted plasma C1q. Factor B-deficient and C3-deficient mice, generated by gene targeting, proved to be as sensitive to TNF/GalN as control mice. Furthermore, induction of lethal shock by platelet-activating factor, an important mediator in TNF-induced hepatic failure, was not reduced in C3-deficient mice. These data indicate that complement, although activated, plays no major role in the generation of acute lethal hepatic failure in this model and that CVF-induced protection is independent of complement depletion

A Dietary Supplement Containing Chlorophytum Borivilianum

BACKGROUND: Impaired sleep quality is commonplace within industrialized societies, as evidenced by the increasing number of prescription sleep aids available. Certain herbal preparations have been suggested to provide a natural benefit to sleep; however, limited controlled data are available documenting this benefit. In the present study we tested the effect of an experimental dietary supplement, containing the active ingredients Chlorophytum borivilianum and Velvet bean, on sleep quality using the Pittsburgh Sleep Quality Index (PSQI). METHODS: Eighteen healthy and active men and women, with evidence of impaired sleep quality, consumed the supplement daily for 28 days. The PSQI was administered before and after the intervention period. As indicators of safety, resting heart rate and blood pressure were measured, and a complete blood count, comprehensive metabolic panel, and lipid panel were determined. RESULTS: Sleep quality was influenced by the supplement, as evidenced by an improvement in every category of the PSQI questionnaire (P < 0.05), with most category scores improving approximately 50% from pre to post intervention. No adverse outcomes were noted with use of the supplement, as indicated by no change in resting heart rate, blood pressure, or any bloodborne parameter. CONCLUSIONS: An investigational dietary supplement containing the active ingredients Chlorophytum borivilianum and Velvet bean improves sleep quality in men and women. Additional placebo controlled trials are needed to corroborate these findings in individuals with self-reported sleeping difficulty