Artwork: huxley.media via DALL·E
With the latest scientific discoveries, it seems that all is not so clear in the world of dreams. Short nights can bring not only fatigue but also some benefits, especially if new research on the effects of sleep deprivation on depression is to be believed. In the world of science, as always, nothing is ever very simple.
Sleep disorders and depression often go hand in hand. A study on the effects of sleep deprivation on depression in mice may have implications for depression treatment methods in humans. The methods of holistic therapy for depression refers to — controlled sleep restriction or changes in sleep patterns.
In an experiment conducted by a team of scientists from Northwestern University, USA, male C57BL/6 J mice were subjected to chronic stress. C57BL/6J is a strain of laboratory mice used in scientific research. These mice are known for their genetic homogeneity and are widely used in experiments in genetics, immunology and oncology, as well as in research related to neuroscience and behavioral biology.
Results published in November 2023 by scientists show that after six hours of sleep deprivation, mice experienced a rapid and effective reduction in depressive behavioral responses. In other words, when the mice experienced sleep deprivation, it reduced immune and inflammatory responses. We can think of this as slowing down the body’s «defense system», which sometimes becomes overactive when depressed, causing excessive «inflammation» in the body.
Analysis of molecules carrying genetic information revealed that after stress, activated immune and inflammatory pathways were suppressed during sleep deprivation. Sleep deprivation also normalized the activity of immune and inflammatory RNA molecules, inflammatory factors and microglia activation in the anterior cingulate cortex.
The scientists also found that sleep deprivation improved neuroplasticity in the prefrontal cortex and anterior cingulate cortex. This meant increased brain adaptability, meaning the brain became more «plastic» and able to recover from stress. Sleep deprivation can act as an antidepressant: studies show that sleep restriction can alleviate symptoms of depression. However, don’t be in a hurry to experiment with it on yourself — such «treatment» can have serious side effects.
But here’s the interesting thing: scientists have learned more about what happens in the brain during sleep deprivation, and are now working to develop medications that can imitate its positive effects without the risk of exhaustion or mania.
These findings offer new perspectives on understanding the complex links between sleep and mental health, which could influence future treatments for depression.
Depressive behavior in mice has been used as a model to study human depression, but it should be understood that the phenomena are not identical. Mice exhibit changes in activity, eating, and interaction that may be similar to symptoms of depression in humans, such as loss of interest in usual activities or social isolation.
However, human depression involves more complex emotional, cognitive, and psychological aspects that are difficult to fully replicate in an animal model of behavior. The Beck Depression Inventory (BDI) is one of the most popular tools for assessing the severity of depressive symptoms.
It is widely used both in clinical practice and for research purposes due to its simplicity, reliability and validity. The test includes questions assessing mood, pessimism, guilt, social alienation and physical symptoms.
Therefore, despite the positive effects of sleep restriction for the treatment of depression in mice, human studies are needed to confirm these findings and develop specific treatment protocols.
The importance of the study cannot be overemphasized, as the research provides a foundation for non-pharmacologic treatment of depression. This is especially important for people who cannot take antidepressants due to side effects and medical contraindications.
In addition, non-pharmacologic methods may be more sustainable in the long term, given the complex relationship between sleep and mental health.
The good news is that the results already provide a theoretical basis for the clinical application of sleep deprivation as a fast-acting antidepressant treatment.
Original research: Dopamine pathways mediating affective state transitions after sleep loss, Neuron, available online 2 November 2023