Tel Aviv University researcher finds an autoimmune process plays major role in triggering neurological disorder
Falling asleep without warning, anywhere, anytime, is one of the hallmarks of narcolepsy. And for the three million narcoleptics worldwide, these bouts of sleepiness and sleep attacks are a severe disruption to daily life. Now, a new Israeli study may finally offer a path to treatment.
The world’s leading autoimmune disease expert, Tel Aviv University’s Prof. Yehuda Shoenfeld, has found that narcolepsy bears the trademarks of a classic autoimmune disorder and should be treated accordingly.
The research, led by Prof. Shoenfeld, the Laura Schwarz-Kipp Chair for Research of Autoimmune Diseases at TAU’s Sackler Faculty of Medicine and Head of Zabludowicz Center for Autoimmune Diseases at Chaim Sheba Medical Center, Tel Hashomer, and conducted by doctoral student María-Teresa Arango, points to a particular autoimmune process as the trigger for the specific loss of orexin neurons, which maintain the delicate equilibrium between sleep and wakefulness in the brain.
“Our hope is to change the perception and diagnosis of narcolepsy, to define it as the 81st known autoimmune disease, because a better understanding of the mechanism causing this disease, which debilitates and humiliates so many people, will lead to better treatment and, maybe one day, a cure,” says Prof. Shoenfeld.
Narcolepsy first strikes people aged 10 to 25, plaguing them for life. Narcoleptics may experience any or all of the following symptoms: falling asleep without warning, making it difficult to concentrate and fully function; excessive daytime sleepiness; the sudden loss of muscle tone; slurred speech or weakness of most muscles for a few seconds or a few minutes; a temporary inability to move or speak while falling asleep or upon waking; and hallucinations.
Prof. Shoenfeld and his team collaborated with a Japanese research group led by Dr. Makoto Honda to isolate specific antibodies. These antibodies were then injected directly into laboratory mice. Arango monitored their behavior for several months, tracking their sleep patterns. “What we saw was an increased number of sleep attacks and irregular patterns of sleep in mice,” says Prof. Shoenfeld. “Mice fall asleep like dogs, circling around before going to sleep. Suddenly, in this experiment, the mice just dropped off to sleep and then, just two minutes later, woke up as though nothing happened.
“Narcolepsy is interesting, because although it has been considered to be strictly genetic, it is induced by environmental factors, such as a burst of laughter or stress,” says Prof. Shoenfeld. “Narcolepsy is devastating to those suffering from it and debilitating to children, in particular. There is no known therapy to treat it.”
The research was published in Pharmacological Research. (Israel 21c)