title: Insulin resistance in Alzheimer's disease.
abstract: Insulin is a key hormone regulating metabolism. Insulin binding to cell surface insulin receptors engages many signaling intermediates operating in parallel and in series to control glucose, energy, and lipids while also regulating mitogenesis and development. Perturbations in the function of any of these intermediates, which occur in a variety of diseases, cause reduced sensitivity to insulin and insulin resistance with consequent metabolic dysfunction. Chronic inflammation ensues which exacerbates compromised metabolic homeostasis. Since insulin has a key role in learning and memory as well as directly regulating ERK, a kinase required for the type of learning and memory compromised in early Alzheimer's disease (AD), insulin resistance has been identified as a major risk factor for the onset of AD. Animal models of AD or insulin resistance or both demonstrate that AD pathology and impaired insulin signaling form a reciprocal relationship. Of note are human and animal model studies geared toward improving insulin resistance that have led to the identification of the nuclear receptor and transcription factor, peroxisome proliferator-activated receptor gamma (PPARγ) as an intervention tool for early AD. Strategic targeting of alternate nodes within the insulin signaling network has revealed disease-stage therapeutic windows in animal models that coalesce with previous and ongoing clinical trial approaches. Thus, exploiting the connection between insulin resistance and AD provides powerful opportunities to delineate therapeutic interventions that slow or block the pathogenesis of AD.
authors.affiliation: Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA.
authors.forename: Kelly T
authors.initials: KT
authors.lastname: Dineley
authors.affiliation: Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA.
authors.forename: Jordan B
authors.initials: JB
authors.lastname: Jahrling
authors.affiliation: Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA. Electronic address: ladenner@utmb.edu.
authors.forename: Larry
authors.initials: L
authors.lastname: Denner
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism*; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism*; D004195:Disease Models, Animal; D004660:Encephalitis / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance; D007858:Learning / Q000502:physiology; D020935:MAP Kinase Signaling System; D047495:PPAR gamma / Q000378:metabolism
chemical_list: D016229:Amyloid beta-Peptides; D007328:Insulin; D047495:PPAR gamma
keywords: Alzheimer's disease; Animal models; Cognitive function; ERK; Insulin resistance; Learning and memory; Metabolism; Mitochondria; PPAR gamma; Therapeutic windows