Summarize the recent findings in narcolepsy focusing on the environmental and genetic risk factors in disease development.
Both genetic and epidemiological evidence point towards an autoimmune mechanism in the destruction of orexin/hypocretin neurons. Recent studies suggest both humoral and cellular immune responses in the disease development.
Narcolepsy is a severe sleep disorder, in which neurons producing orexin/hypocretin in the hypothalamus are destroyed. The core symptoms of narcolepsy are debilitating, extreme sleepiness, cataplexy, and abnormalities in the structure of sleep. Both genetic and epidemiological evidence point towards an autoimmune mechanism in the destruction of orexin/hypocretin neurons. Importantly, the highest environmental risk is seen with influenza-A infection and immunization. However, how the cells are destroyed is currently unknown. In this review we summarize the disease symptoms, and focus on the immunological findings in narcolepsy. We also discuss the environmental and genetic risk factors as well as propose a model for disease development.
aDepartment of Psychiatry and Behavioral Sciences, Center for Sleep Sciences, Stanford University School of Medicine, Palo Alto, California, USA
bNational Institute for Health and Welfare, Public Genomics Unit
cInstitute for Molecular Medicine FIMM, University of Helsinki, Helsinki, Finland
Correspondence to Emmanuel Mignot, Stanford University Center for Sleep Sciences, 3165 Porter Drive, Palo Alto, CA 94304, USA. Tel: +1 650 725 6517; fax: +1 650 725 4913; e-mail: firstname.lastname@example.org