HCRTR1 and Alzheimer disease: For example, suvorexant is a dual antagonist of orexin receptors OX1R and OX2R, and sleep deprivation and sleep-promoting orexin signaling were found to influence the levels of AD-related proteins, Aβ and tau, in interstitial fluid or cerebrospinal fluid, respectively, during the sleep/wake cycle [38,98,99,100,101].