Cytokines and Sleep Regulation

Background: Vitamin D exerts multiple pleiotropic effects beyond its role in calcium-phosphate metabolism. Growing evidence suggests an association between hypovitaminosis D and sleep disorders, thus increasing the interest in the role of this vitamin in the regulatory mechanisms of the sleep-wake cycle. Objective: The study aimed to explore and summarize the current knowledge about the role of vitamin D in sleep regulation and the impact of vitamin D deficiency on sleep disorders. Methods: The main regulatory mechanisms of vitamin D on sleep are explained in this study. The literature was scanned to identify clinical trials and correlation studies showing an association between vitamin D deficiency and sleep disorders. Results: Vitamin D receptors and the enzymes that control their activation and degradation are expressed in several areas of the brain involved in sleep regulation. Vitamin D is also involved in the pathways of production of Melatonin, the hormone involved in the regulation of human circadian rhythms and sleep. Furthermore, vitamin D can affect sleep indirectly through non-specific pain disorders, correlated with alterations in sleep quality, such as restless legs syndrome and obstructive sleep apnea syndrome. Conclusions: : Vitamin D has both a direct and an indirect role in the regulation of sleep. Although vitamin D deficiency has been associated to sleep disorders, there is still scant evidence to concretely support the role of vitamin D supplementation in the prevention or treatment of sleep disturbances; indeed, more intervention studies are needed to better clarify these aspects.

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Sleep maturation influences cognitive development of preterm toddlers

Scientific Reports ◽

10.1038/s41598-021-95495-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Akiko Ando ◽

Hidenobu Ohta ◽

Yuko Yoshimura ◽

Machiko Nakagawa ◽

Yoko Asaka ◽

...

Keyword(s):

Cognitive Development ◽

Sleep Duration ◽

Sleep Time ◽

Brain Maturation ◽

Sleep Diary ◽

Sleep Regulation ◽

Wake Time ◽

Daytime Nap ◽

Nighttime Sleep ◽

The Relationship

AbstractOur recent study on full-term toddlers demonstrated that daytime nap properties affect the distribution ratio between nap and nighttime sleep duration in total sleep time but does not affect the overall total amount of daily sleep time. However, there is still no clear scientific consensus as to whether the ratio between naps and nighttime sleep or just daily total sleep duration itself is more important for healthy child development. In the current study, to gain an answer to this question, we examined the relationship between the sleep properties and the cognitive development of toddlers born prematurely using actigraphy and the Kyoto scale of psychological development (KSPD) test. 101 premature toddlers of approximately 1.5 years of age were recruited for the study. Actigraphy units were attached to their waist with an adjustable elastic belt for 7 consecutive days and a child sleep diary was completed by their parents. In the study, we found no significant correlation between either nap or nighttime sleep duration and cognitive development of the preterm toddlers. In contrast, we found that stable daily wake time was significantly associated with better cognitive development, suggesting that sleep regulation may contribute to the brain maturation of preterm toddlers.

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Homeostatic Response to Sleep Restriction in Adolescents

SLEEP ◽

10.1093/sleep/zsab106 ◽

2021 ◽

Author(s):

Jelena Skorucak ◽

Nathan Weber ◽

Mary A Carskadon ◽

Chelsea Reynolds ◽

Scott Coussens ◽

...

Keyword(s):

Slow Wave ◽

Process Model ◽

Animal Studies ◽

Sleep Restriction ◽

Sleep Regulation ◽

Homeostatic Process ◽

Sleep Homeostasis ◽

High Prevalence ◽

Homeostatic Response ◽

Chronic Sleep

Abstract The high prevalence of chronic sleep restriction in adolescents underscores the importance of understanding how adolescent sleep is regulated under such conditions. One component of sleep regulation is a homeostatic process: if sleep is restricted, then sleep intensity increases. Our knowledge of this process is primarily informed by total sleep deprivation studies and has been incorporated in mathematical models of human sleep regulation. Several animal studies, however, suggest that adaptation occurs in chronic sleep restriction conditions, showing an attenuated or even decreased homeostatic response. We investigated the homeostatic response of adolescents to different sleep opportunities. Thirty-four participants were allocated to one of three groups with 5, 7.5 or 10 h of sleep opportunity per night for 5 nights. Each group underwent a protocol of 9 nights designed to mimic a school week between 2 weekends: 2 baseline nights (10 h sleep opportunity), 5 condition nights (5, 7.5 or 10 h), and two recovery nights (10 h). Measures of sleep homeostasis (slow-wave activity and slow-wave energy) were calculated from frontal and central EEG derivations and compared to predictions derived from simulations of the homeostatic process of the two-process model of sleep regulation. Only minor differences were found between empirical data and model predictions, indicating that sleep homeostasis is preserved under chronic sleep restriction in adolescents. These findings improve our understanding of effects of repetitive short sleep in adolescents.

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Cellular Effects of Rhynchophylline and Relevance to Sleep Regulation

Clocks & Sleep ◽

10.3390/clockssleep3020020 ◽

2021 ◽

Vol 3 (2) ◽

pp. 312-341

Author(s):

Maria Neus Ballester Roig ◽

Tanya Leduc ◽

Cassandra C. Areal ◽

Valérie Mongrain

Keyword(s):

Sleep Time ◽

Sleep Regulation ◽

Neuronal Communication ◽

Cellular Effects ◽

Pathological Conditions ◽

Extracellular Signal ◽

Mitogen Activated Protein ◽

Cellular Pathways ◽

Phosphoinositide 3 Kinase ◽

Protein Kinase Akt

Uncaria rhynchophylla is a plant highly used in the traditional Chinese and Japanese medicines. It has numerous health benefits, which are often attributed to its alkaloid components. Recent studies in humans show that drugs containing Uncaria ameliorate sleep quality and increase sleep time, both in physiological and pathological conditions. Rhynchophylline (Rhy) is one of the principal alkaloids in Uncaria species. Although treatment with Rhy alone has not been tested in humans, observations in rodents show that Rhy increases sleep time. However, the mechanisms by which Rhy could modulate sleep have not been comprehensively described. In this review, we are highlighting cellular pathways that are shown to be targeted by Rhy and which are also known for their implications in the regulation of wakefulness and sleep. We conclude that Rhy can impact sleep through mechanisms involving ion channels, N-methyl-d-aspartate (NMDA) receptors, tyrosine kinase receptors, extracellular signal-regulated kinases (ERK)/mitogen-activated protein kinases (MAPK), phosphoinositide 3-kinase (PI3K)/RAC serine/threonine-protein kinase (AKT), and nuclear factor-kappa B (NF-κB) pathways. In modulating multiple cellular responses, Rhy impacts neuronal communication in a way that could have substantial effects on sleep phenotypes. Thus, understanding the mechanisms of action of Rhy will have implications for sleep pharmacology.

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Altered Circadian and Homeostatic Sleep Regulation in Prokineticin 2-Deficient Mice

SLEEP ◽

10.1093/sleep/30.3.247 ◽

2007 ◽

Cited By ~ 1

Keyword(s):

Sleep Regulation ◽

Prokineticin 2 ◽

Deficient Mice

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Brain-derived neurotrophic factor enhances spontaneous sleep in rats and rabbits

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1999.276.5.r1334 ◽

1999 ◽

Vol 276 (5) ◽

pp. R1334-R1338 ◽

Cited By ~ 18

Author(s):

Tetsuya Kushikata ◽

Jidong Fang ◽

James M. Krueger

Keyword(s):

Growth Factors ◽

Neurotrophic Factor ◽

Brain Temperature ◽

Brain Derived Neurotrophic Factor ◽

Normal Brain ◽

Sprague Dawley ◽

Sleep Regulation ◽

Bdnf Mrna ◽

Sprague Dawley Rats ◽

Intracerebroventricular Injections

Various growth factors are involved in sleep regulation. Brain-derived neurotrophic factor (BDNF) belongs to the neurotrophin family; it and its receptors are found in normal brain. Furthermore, cerebral cortical levels of BDNF mRNA have a diurnal variation and increase after sleep deprivation. Therefore, we investigated whether BDNF would promote sleep. Twenty-four male Sprague-Dawley rats (320–380 g) and 25 male New Zealand White rabbits (4.5–5.5 kg) were surgically implanted with electroencephalographic (EEG) electrodes, a brain thermistor, and a lateral intracerebroventricular cannula. The animals were injected intracerebroventricularly with pyrogen-free saline and, on a separate day, one of the following doses of BDNF: 25 or 250 ng in rabbits; 10, 50, or 250 ng in rats. The EEG, brain temperature, and motor activity were recorded for 23 h after the intracerebroventricular injections. BDNF increased time spent in non-rapid eye movement sleep (NREMS) in rats and rabbits and REMS in rabbits. Current results provide further evidence that various growth factors are involved in sleep regulation.

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