Narcolepsy, the disease that triggers uncontrollable sleep attacks, no longer has any secrets for medical science. According to a recent discovery at its origin there would be the ‘cancellation’ of a chemical messenger in the brain by the cells of the immune system. The discovery, published in the journal Nature, is due to research conducted in Switzerland by Italian researchers and is the result of collaboration between the Research Institute in Biomedicine in Bellinzona (affiliated to the University of Lugano), the Polytechnic of Zurich and the Department of Neurology of Inselspital in Bern. We commented on these results with Dr. Vincenzo Tullo, neurologist at Humanitas.
Sleepiness, a wake-up call for many sleep disorders
Sleepiness is the condition in which you sleep during the day and can lead to falling asleep in inappropriate situations and at inappropriate times. This excessive daytime sleep may be a symptom of inadequate rest associated with shift work, depression, stress, anxiety, but also physical problems such as chronic pain, diabetes, changes in sodium levels, narcolepsy, sleep apnea, hypothyroidism, hypercalcemia or taking certain medications (such as antihistamines or tranquilizers).
Hypocretin attacked by immune cells
The neurotransmitter called hypocretin, involved in the regulation of the sleep-wake rhythm, is cancelled because the neurons that produce it are attacked by immune cells called T lymphocytes. Researchers discovered it by analyzing, in patients affected by narcolepsy, the presence of cells in the immune system, the T lymphocytes, which recognize the hypocretin and can kill directly or indirectly the neurons that produce it.
The hypothesis of blocking the disease
“Thanks to the use of new experimental methods we have been able to identify the specific T lymphocytes for hypocretin as responsible for this disease – explained Federica Sallusto, of the Institute for Research in Biomedicine -. These self-reactive lymphocytes can cause inflammation that leads to neuronal damage or even kill the neurons that produce hypocretin. Blocking them in the early stages could prevent the progression of the disease.