Mount Sinai researchers have identified a novel mechanism that might link type 2 diabetes to Alzheimer's disease.
Lead researcher Dr. Giulio Maria Pasinetti said that the relationship between type-2 diabetes and Alzheimer's disease is elusive. Not all subjects with type-2 diabetes are affected by Alzheimer's disease, and similarly, not all Alzheimer's disease cases are diabetic.
However, recent studies have shown that people affected by type-2 diabetes are twice as likely to develop Alzheimer's disease dementia. But the reason is not known.
In the new study, the research team has found that a gene known as proliferator-activated receptor coactivator 1 - (PGC-1), a key regulator of glucose content, a potential therapeutic target for type-2 diabetes, is also decreased in Alzheimer' disease dementia cases.
Moreover, PGC-1 decreased in Alzheimer' disease dementia cases with progression of the clinical disease and led to the accumulation of ß-amyloid, an abnormal protein highly linked to Alzheimer' disease dementia and brain degeneration.
"This new evidence is of extreme interest especially because of the evidence that approximately 60percent of Alzheimer's disease dementia cases have at least one serious medical condition primarily associated with type-2 diabetes, a chronic condition which includes high blood glucose content (hyperglycemia) and reduced sensitivity to insulin, among other conditions," said Dr Pasinetti.
"Of considerable interest is the evidence found in further mechanistic studies in our laboratory, indicating that promoting PGC-1 content in brain cells, using a transgenic mouse model of Alzheimer's disease, attenuates hyperglycemic-mediated production of ß-amyloid, highly linked to Alzheimer' disease dementia.
"These findings are very exciting, and for the first time tentatively link type-2 diabetic metabolic defects to increasing dementia mediated by ß-amyloid production," he added.
The study appears in scientific journal, Archives of Neurology.