Neurodegenerative Diseases And Sleep Disorders

Neurodegenerative diseases are conditions in which the neurons in the central nervous system stop working or die slowly, causing various neurological signs and symptoms.

These conditions tend to worsen over time and are incurable. They can manifest themselves due to a genetic component, a tumor or a stroke. These diseases are also more common in people who drink a lot of alcohol or who are exposed to certain viruses and toxins.

Sleep disorders can also affect the manifestation of neurodegenerative diseases. A study from the University of Toronto showed that REM sleep disorders can be an early sign of neurodegenerative diseases.

All about dreaming

From the 60’s, researchers have claimed that dreams arise in the REM stage and that the brain stem is an important area to control them. This part of the brain communicates with the hypothalamus to create the transition from wakefulness to sleep and vice versa.

Thus, the glutamatergic SubC cells (which regulate the transition between REM sleep and NREM sleep) start a chain reaction. These cells got their name from the brain area they belong to: subcoeruleus nucleus or SubC. The reaction causes the release of GABA neurotransmitter which simultaneously reduces the activity level in the hypothalamus and brainstem. In fact, GABA neurons are responsible for controlling REM sleep and especially muscle paralysis during deep sleep.

When these cells begin to activate, there is a rapid transition to REM sleep. The brain stem sends signals so that the muscles relax and the limbs do not move. With this in mind , researchers attempted to analyze REM sleep disorders such as cataplexy, narcolepsy, and REM sleep behavior disorder.

REM sleep behavior disorder and neurodegenerative diseases

People who suffer from REM sleep disorder move their limbs or even get up from their bed while still dreaming. In fact, some patients may even talk or shout.

Doctors believe that this pathology makes the sick a danger to themselves or others around them. Sometimes the negative consequences are self-harm or harming the person they are sleeping with a warning for a diagnosis.

Sleep stages

Sleep includes different stages: wakefulness, REM sleep and NREM sleep. Many properties define each step. To understand REM sleep behavior disorder, it is important to know what happens during this stage.

At this stage, the electrical activity of the brain is similar to that you have when you are awake. Although neurons in the brain during REM sleep work in the same way as when you are awake, REM sleep includes a temporary paralysis of the muscles.

In some sleep disorders such as narcolepsy, parasomnia or REM sleep behavior disorder, there is almost no difference between the different stages. Experts believe that “neurological barriers” that separate stages of sleep do not work properly, although the cause of these phenomena is not yet clear.

Therefore, most people are unable to touch their bodies even when they have vivid dreams. However, people with REM sleep disorders lack muscle paralysis. This allows them to move their bodies while having violent dreams.

REM sleep disorders and their association with neurodegenerative diseases

Researchers have discovered something very interesting: REM sleep disorders are related to several neurodegenerative diseases that tend to manifest in older people. These findings suggest that the neurodegenerative processes initially affect the REM sleep circuits, and more specifically the SubC neurons.

They also observed that more than 80% of people suffering from REM sleep disorder develop synucleinopathies over time, such as Parkinson’s disease and dementia with Lewy bodies (DLL).

This research suggests that sleep disorders may be an early sign of neurodegenerative diseases that may manifest 15 years later.

You should also note that both Parkinson’s disease and DLL are related to an abnormal intranevronal accumulation of alpha-synuclein proteins. This is why researchers expect that the study of the mentioned protein will make it easier to know which neuroprotective therapies would prevent the development of neurodegenerative disease.

Experts also claim that just like in cancer-prone patients, the diagnosis of REM sleep disorders can lead to preventative measures to preserve your neuronal health before more serious neurological conditions begin to develop.