Fifteen years ago, orexins were identified as central regulators of energy homeostasis. Research indicates that orexins are key modulators of the sleep-wake cycle and that these neuropeptides also affect feelings of satiety and hunger. Given their role in energy homeostasis, it was hypothesized that orexin levels are likely regulated, at least in part, by the growth hormone axis. Recent research supports this fact and suggests that growth hormone releasing hormone analogues, such as sermorelin, may be effective in treating conditions in which orexin release is dysfunctional (e.g. narcolepsy) [1].
