A look inside the diabetic brain: Contributors to diabetes-induced brain aging

Department of Pharmacology, Physiology and Neuroscience University of South Carolina, School of Medicine, Columbia, SC 29208, USA.
Biochimica et Biophysica Acta (Impact Factor: 4.66). 12/2008; 1792(5):444-53. DOI: 10.1016/j.bbadis.2008.10.013
Source: PubMed


Central nervous system (CNS) complications resulting from diabetes is a problem that is gaining more acceptance and attention. Recent evidence suggests morphological, electrophysiological and cognitive changes, often observed in the hippocampus, in diabetic individuals. Many of the CNS changes observed in diabetic patients and animal models of diabetes are reminiscent of the changes seen in normal aging. The central commonalities between diabetes-induced and age-related CNS changes have led to the theory of advanced brain aging in diabetic patients. This review summarizes the findings of the literature as they relate to the relationship between diabetes and dementia and discusses some of the potential contributors to diabetes-induced CNS impairments.

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    • "The continuous generation of reactive oxygen species (ROS) and pro-inflammatory cytokines (interleu- kin-1b and tumor necrosis factor-a), show greater relevance because their accumulation leads to the progressive loss of cellular function until the death of tissues (Ejerblad et al., 2006). In recent years it has been shown that the MS could affect the functioning of the CNS by inducing morphological, electrophysiological , and cognitive changes (Biessels et al., 2008; Wrighten et al., 2009). The MS has been suggested as a risk factor for Alzheimer's disease and vascular dementia, which are associated with cognitive dysfunction (Whitmer, 2007). "
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    ABSTRACT: A high calorie intake can induce the appearance of the metabolic syndrome (MS), which is a serious public health problem because it affects glucose levels and triglycerides in the blood. Recently, it has been suggested that MS can cause complications in the brain, since chronic hyperglycemia and insulin resistance are risk factors for triggering neuronal death by inducing a state of oxidative stress and inflammatory response that affect cognitive processes. This process, however, is not clear. In this study, we evaluated the effect of the consumption of a high-calorie diet (HCD) on both neurodegeneration and spatial memory impairment in rats. Our results demonstrated that HCD (90 day consumption) induces an alteration of the main energy metabolism markers, indicating the development of MS in rats. Moreover, an impairment of spatial memory was observed. Subsequently, the brains of these animals showed activation of an inflammatory response (increase in reactive astrocytes and interleukin1-β as well as tumor necrosis factor-α) and oxidative stress (reactive oxygen species and lipid peroxidation), causing a reduction in the number of neurons in the temporal cortex and hippocampus. Altogether, these results suggest that a HCD promotes the development of MS and contributes to the development of a neurodegenerative process and cognitive failure. In this regard, it is important to understand the relationship between MS and neuronal damage in order to prevent the onset of neurodegenerative disorders. This article is protected by copyright. All rights reserved. © 2015 Wiley Periodicals, Inc.
    Synapse 06/2015; 69(9). DOI:10.1002/syn.21832 · 2.13 Impact Factor
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    • "A recent metaanalysis showed that T1D adults perform worse on tests of full/ verbal and performance IQ, executive function, memory, spatial memory, and motor speed (Tonoli et al. 2014). This cognitive decline has been ascribed to episodes of hypoglycaemia (Auer 2004), hyperglycaemia (Wrighten et al. 2009), and C-peptide and/or insulin deficiencies (Li et al. 2005) as a pathophysiological basis. Over the last several decades much research in nondiabetic subjects has been carried out to identify the influence of acute and chronic physical exercise on cognitive function. "
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    Applied Physiology Nutrition and Metabolism 01/2015; 40(1). DOI:10.1139/apnm-2014-0098 · 2.34 Impact Factor
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    • "There is substantial evidence that diabetes mellitus (DM) may have a negative impact on the central nervous system, and that cognitive impairment is the most common symptom of this condition1,2,3. Hyperglycemia-associated microvascular changes in the brain are responsible for the cognitive decline in patients with type 1 diabetes mellitus (T1DM); intensive insulin therapy for the treatment of T1DM results in improved glycemic control. Additionally, insulin treatment aims toward correcting the deficits in spatial learning and memory4,5. "
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    Acta Pharmacologica Sinica 03/2013; 34(4). DOI:10.1038/aps.2013.11 · 2.91 Impact Factor
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