Restitution and human sleep: A critical review

Abstract

It is often assumed that human non-REM sleep, especially its apparently more intense form of slow-wave sleep (SWS), is associated with large increases in body restitutional processes, for example, protein synthesis. However, findings from total sleep deprivation appear only to support a brain restitutional role for human sleep and not one of body restitution. Although rises in human growth hormone (hGH) release during SWS might support a body restitutional role, the variety of complex actions of hGH indicate that other effects, particularly the redistribution of energy substrates, are likely. Sleep hGH release may be a misleading factor in the understanding of SWS function. Increases in protein synthesis during human sleep are unlikely for several reasons. The elevation of mitosis which can occur in sleep is probably a concomitant phenomenon. While relaxed wakefulness should provide for man's body restitutional need, the lack of such a relaxed state in certain mammals may necessitate that sleep fulfills this need for these animals. Although REM sleep, alone, is generally considered to be for cerebral restitution, evidence in support of this viewpoint needs qualification. It is argued that non-REM sleep, especially SWS, is of equal benefit to the human brain.Among sleep researchers, the opinion is generally held that sleep is a state of enforced rest and energy conservation, wherein both body and brain can recover from the wear and tear of wakefulness. Ostensibly, non-REM (nondreaming) sleep is considered to be oriented towards promotion of the synthetic processes of growth and repair in the body, and REM (dreaming) sleep is believed to be directed towards increases in synthetic processes within the brain, including the consolidation of memory. The purpose of this review is to appraise these assumptions for the functions of sleep, with particular regard to man.

How to benefit from weekend physical activities: Moderating roles of psychological recovery experiences and sleep

“…Sleep, one of the most fundamental restoration processes, cleans toxic metabolites from the brain, boosts muscle mass, repairs body cells and tissues, and balances hormones that affect a wide range of physiological health markers (Cappuccio, D'Elia, Strazzullo, & Miller, ; Horne, ). The sleep literature has mainly considered physical activity (e.g., exercise) as one of the important sleep hygiene factors (Irish, Kline, Gunn, Buysse, & Hall, ).…”

Possible Role of Pineal Melatonin in the Mechanisms of Aging

“…Administration of melatonin is associated with several metabolic changes in the hypothalamus including alterations in protein synthesis, uptake of neurotransmitters including dopamine, serotonin, norepinephrine, and gamma-amino-butyric acid (GABA), release of neuropeptides, hormones and prostaglandins (Erlich & Apuzzo, 1985). This cascade of neurotransmitters, neuropeptides and neurohormones represents an entire system involved in regenerative and reparative functions acting in synchrony during the period of darkness (Horne, 1979;Datta & King, 1980). It has been suggested that the mechanisms of action of melatonin are mediated through cellular microtubules (Winston et al, 1974).…”

“…We recently noted the emergence of spontaneous abnormal perioral movements in young, drug-naive pinealectomized rats with further augmentation of these movements following administration of haloperidol (Sandyk & Fisher, 1989). 6) There is evidence to suggest that slow-wave sleep (SWS) is associated with significant increases in cerebral restitutional processes (Horne, 1979) with reduction of SWS in subjects of advancing age (Mendelson et al, 1980). 6) There is evidence to suggest that slow-wave sleep (SWS) is associated with significant increases in cerebral restitutional processes (Horne, 1979) with reduction of SWS in subjects of advancing age (Mendelson et al, 1980).…”