The Impact of Diabetes on Cerebral Structure and Function

Abstract

Diabetes alters cerebral metabolism, structure, and function. Both hyperglycemia and therapy-associated hypoglycemia are believed to have an impact on the brain, and this impact may depend on the age of the individual, their stage of neurological development, and whether they have Type 1 or Type 2 diabetes. Hypoglycemia in children with Type 1 has consistently been associated with a reduction in neurocognitive function, but such a finding has not been seen in adults with Type 1 diabetes. Both hypoglycemia and hyperglycemia have been linked with dementia in adults with Type 2 diabetes. In both Type 1 and Type 2 diabetes, recurrent episodes of treatment-associated hypoglycemia impair how well the brain can sense and respond to subsequent episodes of hypoglycemia. In this brief review, we will review how diabetes affects the brain with a focus on investigations done in our own laboratory. We have focused on using high magnetic field imaging and spectroscopy to identify subtle changes in brain structure and metabolism that may contribute to the long-term cerebral complications of diabetes. We have found evidence of microstructural changes in white matter regions, reduced gray matter density, and reduced activation of the thalamus in response to recurrent hypoglycemia in patients with Type 1 diabetes.

Divergent Influences of Cardiovascular Disease Risk Factor Domains on Cognition and Gray and White Matter Morphology

“…Similarly, only GluDys-related FA alterations associated with poorer cognitive functioning suggesting this was the most consistent of our brain/behavior relationship findings. While these results may highlight the unique information derived by the examination of empirically derived CVD-RF domains, when combined with our results using age as a moderator variable, this study highlights the importance of considering how age may influence brain/behavior associates of CVD-RFs – an area of increased interest across multiple CVD-RFs (49–51). …”

Midlife Metabolic Profile and the Risk of Late-Life Cognitive Decline

“…Additionally, prediabetes and impaired glucose regulation have been found to increase the risk of developing CD [20]. Since dysregulations of blood glucose concentrations have been linked to compromised neurocognitive functions [2], the majority of prediabetes and type 2 DM research has focused on the effects of glycemia and insulin signaling within the brain [21]. Decreases in the sensitivity of central nervous pathways to insulin, i.e., brain insulin resistance (IR), constitute a potential link between metabolic and cognitive dysfunctions [22].…”

The diabetic brain and cognition

“…Both T1DM and T2DM induce regional microstructural changes in cortical and subcortical brain structures that are associated with impairment of neurocognitive functions (Seaquist 2015). Some autopsy studies stated that patients with DM have significantly less AD pathology but more frequent cerebrovascular lesions including microvascular changes (Alafuzoff et al 2009;Beeri et al 2005;Nelson et al 2009;Ahtiluoto et al 2010) or both types of cerebral pathology (Alafuzoff et al 2009;Vagelatos and Eslick 2013;Ahtiluoto et al 2010;Takeda et al 2011;Verdile et al 2015), and white matter lesions (Jellinger 2015a, b).…”