Relationship Between Plasma Insulin Level and Apolipoprotein E Gene Polymorphysm in Alzheimer′s Disease

Objective: To study relationship between plasma insulin level and apolipoprotein E Gene polymorphysm in Alzheimcr′s Disease. Background: Recent researches have shown that there was a close relationship between ApoE- ε 4 allele and AD. Because of the discovery of hyperinsulineamia in AD patients, the study of insulin on the pathogenesis of AD become a hot point of AD reseearch. Methods: We apply PCR-RFLP to the ApoE genotype study of 45 AD paticnts and 32 normal controls. At the same time, plasma insulin and glucose level was measured in the abovc objects. Results and Discussion: The frequency of ApoE- ε 4 in AD (32.2%) is much higher than in controls (10.9%). On the contrary, the frequency of ApeE- ε 4 is relatively lower in AD than in thc controls. The resistence of hyperinsulineamia in AD. Insulin sensitivity decreased in AD. Conclusion: When gene dose of ApoE- ε 4 increases, the prcvalance of AD increase, while the on-set ages of AD decrease (P＜0.05). These findings indicatc that AD patients may have insulin resistance anbd insulin probably play a role in AD pathogenesis. In addition, the s 4 homozygote AD patients seem to have loweer plasma insulin level that the non- ε 4 homozygote AD patients (P＜0.05). But this situation need to be replicated in studies of larger sample.