In the enigmatic realm of sleep, often embodied by Morpheus, the Greek god of dreams, we find a complex interplay of modern lifestyle factors and ancient mythology. Morpheus, believed by the ancients to shape dreams, symbolises the enduring human intrigue with the mysterious and restorative aspects of sleep.
Why
Sleep is a universal phenomenon observed across various species, from simple creatures like jellyfish to complex organisms like humans, indicating its importance in our lives[1]. It is regulated by two mechanisms: the circadian clock, which determines when we should sleep, and the sleep homeostat, which adjusts the intensity and duration of sleep according to previous periods of wakefulness. Despite seemingly taking away valuable time from activities like feeding, mating, or protecting ourselves, sleep plays a vital role in preserving optimal physiological and behavioural performance.
How
The process of sleep is governed by complex interactions between neuronal and glial components, internal body clocks, and external factors such as light and dark cycles and temperature variations. The role of astrocytes in the sleep-wake cycle introduces an additional dimension of complexity to our understanding of how sleep is regulated[2].
This fascination is juxtaposed with the pressing issue of insomnia, which affects up to one third of adults globally[3]. Insomnia often coexists with various medical conditions, such as mental, metabolic, or cardiovascular diseases, underscoring its multifaceted nature and the imperative for comprehensive treatment approaches. After decades of research, the case can be confidently made that sleep loss and sleep disorders have profound and widespread effects on human health[4].
Help
HelpInsomnia is associated with an abnormal state of hyperarousal (increased somatic, cognitive, and cortical activation) and orexin a brain neuropeptide (neurotransmitter) has been identified as a key promotor of arousal and vigilance. It is produced in the hypothalamus. Out of the billions of cells in the brain, there are only 10,000 to 20,000 cells that produce orexin[5].
In recent decades, the landscape of sleep research has seen significant advancements, yet the fundamental mechanisms governing sleep and wakefulness continue to elude complete understanding. Neuroscientist Masashi Yanagisawa stands at the vanguard of this research, exploring the intricacies of sleep which may eventually revolutionise both daily living and broader health management strategies. One of the pivotal discoveries in this field is the identification of orexin neuropeptides, initially linked to feeding behaviours but now recognised as critical regulators of arousal and vigilance.
The pioneering identification of orexin-A and -B and the related orexin system in 1998 by researchers, including Yanagisawa’s team at the University of Texas Southwestern, revealed a new signalling pathway that plays a central role in maintaining wakefulness and responding to environmental cues. This system adjusts our level of arousal based on a variety of factors, including emotional states and the sleep/wake cycle, highlighting its complexity and the dynamic nature of its regulatory mechanisms.
The activity of orexin neurons is intricately linked not only to circadian rhythms but also to emotional responses[6]. For instance, positive emotions and social interactions can enhance the activity of these neurons, influencing vigilance levels. Recent studies have also demonstrated how the orexin system promotes wakefulness by inhibiting sleep centres in the brain, such as the ventrolateral preoptic area (VLPO), thereby modulating sleep patterns.
Plant Orexin Antagonists
Amidst this, certain plants have been identified as sources of natural orexin antagonists, offering potential therapeutic benefits for those suffering from chronic insomnia[7]. These include:
- Plumula Nelumbinis, commonly known as Nelumbo nucifera.
- Ziziphus jujuba Mill. Var, known as Jujube.
- Lilium lancifolium Thumb, referred to as Tiger Lily.
- Panax ginseng C.A Mey, known as Asian Ginseng.
These plants contain compounds that can help stabilise sleep and provide relief from insomnia, illustrating how both ancient remedies and cutting-edge science contribute to our growing understanding of sleep’s complexities. As research continues to unfold, the insights gained promise not only to deepen our understanding of sleep, but also to enhance the effectiveness of interventions designed to treat its disorders. This evolving landscape of sleep science underscores a burgeoning area of relatively novel and new understanding, merging historical wisdom with modern research to address the challenges of sleep in the 21st century.
As researchers like Yanagisawa continue to delve into the complexities of sleep, the industry surrounding it has seen exponential growth, thriving on the widespread demand for improved sleep quality. The market, now valued at nearly $300 billion, spans a wide array of products and services from high-tech bedding solutions and personalised sleep consultations to wellness tourism and sophisticated sleep-tracking devices. This not only reflects, but also capitalises on our increased awareness of sleep’s critical role in overall health and disease prevention, bolstered by extensive data collected from wearable technologies. The role of nutritional compounds in the management or aggravation of sleep disorders is an area of growing interest, linked to their safety and absence of post-ingestion altered functionality[8].
Supplements to Assist Sleep
The role of food supplements in promoting better sleep has come to the forefront. Supplements like melatonin, magnesium, and valerian root are increasingly recognised for their potential to enhance sleep quality[9]. Melatonin, for instance, is crucial for regulating the sleep-wake cycle, providing an essential aid for those struggling with disrupted sleeping patterns. Magnesium acts as a natural relaxant, helping to quiet the body and mind, while valerian root is valued for its ability to ease insomnia and anxiety, promoting a more restful night’s sleep. Another safe and effective supplement, L-theanine, found in green tea, or consumed as a supplement at 200mg prior to sleep, is praised for its ability to promote relaxation without inducing drowsiness, thereby supporting better sleep quality[10]. A combination of L-theanine and magnesium has been shown to further enhance sleep quality[11]. Natural sleep aids, are designed to support and enhance the body’s natural sleep cycle rather than override it.
These supplements represent just a fraction of the natural remedies gaining popularity as part of a holistic approach to sleep enhancement. Their growing use is a testament to the shifting attitudes towards health and wellness, where more individuals are seeking natural alternatives to pharmaceutical solutions for sleep issues. The continued integration of these supplements into nightly routines not only reflects a proactive approach to health management but also points to a larger trend in consumer health behaviour, emphasising prevention over treatment.
In-depth comparative studies between natural and synthetic sleep aids have found that while synthetic options may provide quick relief, they might not offer a sustainable solution and can lead to a variety of complications. Natural solutions, on the other hand, foster a healthy sleep environment and nurture the body’s rhythms rather than forcing a sleep state through artificial means.
Comment
As the ‘sleep industry’ continues to expand, the potential for new discoveries and innovations in sleep enhancement is ongoing. With ongoing research and technological advancements, we are on the cusp of a new era in sleep science, one that promises more effective and personalised solutions for combating sleep deprivation and enhancing our quality of life. The future of sleep, fuelled by scientific insights and driven by market innovations, holds the promise of turning what was once a nightly challenge into an optimised, rejuvenating experience, crucial for our health and well-being in a fast-paced world.
References
[1] Joseph D. Jones, Brandon L. Holder, Kiran R. Eiken, Alex Vogt, Adriana I. Velarde, Alexandra J. Elder, Jennifer A. McEllin, Stephane Dissel A Split-GAL4 screen identifies novel sleep-promoting neurons in the Ventral Nerve Cord of Drosophila bioRxiv 2022.02.02.478882
[2] Ghanendra Singh, Astrocytic Sleep Homeostasis Model bioRxiv 2022.10.23.513378;
[3] Bhaskar S, Hemavathy D, Prasad S. Prevalence of chronic insomnia in adult patients and its correlation with medical comorbidities. J Family Med Prim Care. 2016 Oct-Dec;5(4):780-784.
[4] Yun S, Jo S. Understanding insomnia as systemic disease. J Yeungnam Med Sci. 2021;38(4):267-274
[5] Błaszczyk J. W. (2020). Energy Metabolism Decline in the Aging Brain-Pathogenesis of Neurodegenerative Disorders. Metabolites, 10(11), 450.
[6] Inutsuka A, Yamanaka A. The physiological role of orexin/hypocretin neurons in the regulation of sleep/wakefulness and neuroendocrine functions. Front Endocrinol (Lausanne). 2013 Mar 6;4:18.
[7] He J, Fang J, Wang Y, Ge C, Liu S, Jiang Y. Discovery of Small-Molecule Antagonists of Orexin 1/2 Receptors from Traditional Chinese Medicinal Plants with a Hypnotic Effect. Pharmaceuticals (Basel). 2023 Apr 4;16(4):542.
[8] Pattnaik H, Mir M, Boike S, Kashyap R, Khan SA, Surani S. Nutritional Elements in Sleep. Cureus. 2022 Dec 21;14(12):e32803.
[9] Shinjyo N, Waddell G, Green J. Valerian Root in Treating Sleep Problems and Associated Disorders-A Systematic Review and Meta-Analysis. J Evid Based Integr Med. 2020 Jan-Dec;25:2515690X20967323.
[10] Rao TP, Ozeki M, Juneja LR. In Search of a Safe Natural Sleep Aid. J Am Coll Nutr. 2015;34(5):436-47. doi: 10.1080/07315724.2014.926153.
[11] Dasdelen MF, Er S, Kaplan B, Celik S, Beker MC, Orhan C, Tuzcu M, Sahin N, Mamedova H, Sylla S, Komorowski J, Ojalvo SP, Sahin K, Kilic E. A Novel Theanine Complex, Mg-L-Theanine Improves Sleep Quality via Regulating Brain Electrochemical Activity. Front Nutr. 2022 Apr 5;9:874254.
