Modulació del son i de l'activitat cortical a través dels eixos orexina i colinèrgicpaper de l' IGF-I

Resumen

The study of insulin-like growth factor-I (IGF-I) has reached relevance in recent years for its pleiotropic activity, role in brain pathology, and potential therapeutic applications. IGF-I is a circulating hormone mainly produced by the liver under growth hormone (GH) signaling that can cross the blood-brain-barrier (BBB) into the central nervous system (CNS). However, its extensive role in aging and Alzheimer’s disease is not entirely understood. Some studies suggest that IGF-I is involved in adaptive changes during aging, and there is some evidence that supports the notion that Alzheimer’s disease (AD) is also associated with perturbed metabolic function affecting insulin and insulin-like growth factor. Aging and AD are closely related to cortical, information processing, and sleep/wakefulness disturbances, common comorbidities of metabolic diseases. Besides, aging is frequently accompanied by a decline in cognition, and changes in sleep duration are paralleled by changes in IGF-I levels. Furthermore, aging is associated with lower serum IGF-I levels that may contribute to this deterioration. Nonetheless, the underlying processes linking both are not yet fully defined. Here, we take advantage of a specific group of cells involved in sleep regulation and cortical activity. The first group, the orexin neurons, is a discrete cell population in the lateral hypothalamus involved in the circadian sleep/wake cycle, metabolic, energy expenditure, and arousal. The second group, cholinergic cells from the basal forebrain, plays an essential role in cortical function, information processing, and sleep/wake status.