Abstract:

Objective   To explore the association between diabetes-related factors (fasting glucose, fasting insulin and insulin degrading enzyme) and Alzheimer's disease (AD). Methods   32 patients with AD (the patient group) and 30 normal elderly subjects (the control group) were enrolled. Blood samples were used for determining serum fasting insulin (Fins) by chemiluminescence assay and insulin degrading enzyme (IDE) by enzyme linked immunosorbent assay. The two groups were all tested by the mini-mental state examination (MMSE) and clinical dementia rating (CDR). Results   The serum IDE in the patient group declined compared with the control group(P＜0.05). There were positive correlations of fasting glucose (FPG) and Fins with IDE in the control group while no correlations in the patient group. The score of MMSE was negatively correlated with the FPG level in the patient group. And there were no significant differences among the patients in different stages. Conclusion   The IDE level decreases in patients with AD and may influence the function of IDE to adjust the insulin and the insulin resistance, so IDE may play a role in AD.

Key words: Alzheimer disease; Insulin; Insulysin