The impact of diabetes on cognition: what can be learned from rodent models?
Diabetes mellitus is associated with modest impairments in cognition, particularly in the elderly. In addition, the risk of dementia is increased. We review herein studies in rodent models that may help to identify the mechanisms that underlie these adverse effects of diabetes on the brain. Abnormalities in learning and memory, synaptic plasticity, and glutamatergic neurotransmission have now been identified in a number of these models. In general, observations in models characterized by chronic hyperglycaemia and hypoinsulinaemia (referred to as models of type 1 diabetes) are quite consistent, and these models are being increasingly used to study the pathogenesis and to develop new treatments. However, results from models characterized by insulin resistance, hyperinsulinaemia, and modest hyperglycaemia (referred to as models of type 2 diabetes) are much more variable. Moreover, the possible interaction between diabetes and aging has not been examined in sufficient detail. Because clinically relevant cognitive deficits mainly occur in elderly patients with type 2 diabetes, the challenge for researchers in this field will be to further develop adequate models.
Biessels
Geert Jan
GJ
Department of Neurology, G03.228, University Medical Center Utrecht, PO Box 85500, 3508 GA, Utrecht, The Netherlands. g.j.biessels@umcutrecht.nl
Gispen
Willem Hendrik
WH
D000375:Aging / Q000502:physiology; D000818:Animals; D003071:Cognition / Q000502:physiology*; D003920:Diabetes Mellitus / Q000503:physiopathology*; D004195:Disease Models, Animal; D006801:Humans; D051379:Mice; D009473:Neuronal Plasticity / Q000502:physiology; D051381:Rats