AIMS: We previously found that there was a dementia subgroup with characteristics predominantly associated with diabetes mellitus (DM)-related metabolic abnormalities, referred to as "diabetes-related dementia (DrD)." We determined the possible role of oxidative stress in the pathophysiology of DrD. METHODS: In a 2013 study, we classified 175 patients with clinically diagnosed Alzheimer's disease (AD) and DM into four subgroups based on brain imaging. Among them, we measured endogenous plasma anti-oxidants, such as albumin, unconjugated bilirubin and uric acid, and urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane in 58 patients of an AD group showing decreased regional cerebral blood flow of the parietotemporal lobe on single-photon emission computed tomography (AD+DM group), and in 35 patients of a DrD group showing neither decreased regional cerebral blood flow of the parietotemporal lobe nor cerebrovascular disease on magnetic resonance imaging, which is strongly associated with DM-related factors. A total of 31 patients with AD and without DM (AD-DM group) were enrolled as a control group. RESULTS: The DrD group showed a significant decrease in plasma levels of anti-oxidants, and a significant increase in urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane levels in contrast to the AD-DM and AD+DM groups. Cognitive performance was negatively correlated with urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane levels in the DrD group. CONCLUSIONS: These results strongly suggest that a decrease in anti-oxidant levels and an increase in oxidative damage might be involved in the pathophysiology and cognitive decline associated with DrD. Geriatr Gerontol Int 2016; 16: 1312-1318.
AIMS: We previously found that there was a dementia subgroup with characteristics predominantly associated with diabetes mellitus (DM)-related metabolic abnormalities, referred to as "diabetes-related dementia (DrD)." We determined the possible role of oxidative stress in the pathophysiology of DrD. METHODS: In a 2013 study, we classified 175 patients with clinically diagnosed Alzheimer's disease (AD) and DM into four subgroups based on brain imaging. Among them, we measured endogenous plasma anti-oxidants, such as albumin, unconjugated bilirubin and uric acid, and urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane in 58 patients of an AD group showing decreased regional cerebral blood flow of the parietotemporal lobe on single-photon emission computed tomography (AD+DM group), and in 35 patients of a DrD group showing neither decreased regional cerebral blood flow of the parietotemporal lobe nor cerebrovascular disease on magnetic resonance imaging, which is strongly associated with DM-related factors. A total of 31 patients with AD and without DM (AD-DM group) were enrolled as a control group. RESULTS: The DrD group showed a significant decrease in plasma levels of anti-oxidants, and a significant increase in urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane levels in contrast to the AD-DM and AD+DM groups. Cognitive performance was negatively correlated with urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane levels in the DrD group. CONCLUSIONS: These results strongly suggest that a decrease in anti-oxidant levels and an increase in oxidative damage might be involved in the pathophysiology and cognitive decline associated with DrD. Geriatr Gerontol Int 2016; 16: 1312-1318.