No abstract

These results were used to design the multi-center ADCS trial. Doses of less than 1000 mg/day of divalproex sodium were the maximum tolerated by these outpatients with AD. A larger study of divalproex sodium dose tolerability is needed to define treatment in outpatients with Alzheimer's disease.

Type 2 diabetes is a risk factor for late-onset Alzheimer's disease (AD), and studies suggest that pathogenic effects of diabetes and insulin resistance may be associated with non-APOE4 AD. Therefore, we examined association of the APOE4 allele with diabetes in an AD population. Retrospective and cross-sectional clinical and APOE-genotype data on 465 cases with probable or definite AD previously ascertained by the National Institute of Mental Health Genetics Initiative were analyzed by regression analysis. Dependent variables included presence of APOE4 alleles and AD onset age. Diabetes was the independent variable and covariates included gender, hypertension, and other potentially confounding variables. We also examined for interactions involving weight status as overweight and obesity are independent risk factors for insulin resistance, diabetes and AD. Prevalence of diabetes was 13% among AD cases without an APOE4 allele and 5-6% among AD cases with one or two APOE4 alleles. Odds ratio for diabetes was 0.26 [95% CI: 0.09-0.73; P = 0.011] by APOE4 status after adjusting for all covariates. Diabetes did not associate with AD onset age. Among other independent variables included in the model, APOE4 and diuretic medication treatment were associated with AD onset age. In a subset of cases with body mass index determinations, overweight also exhibited an inverse association with APOE4 and associated with decreased non-APOE4 AD onset age. Pathogenic mechanisms associated with diabetes and overweight are enriched in AD cases without an APOE4 allele.

The molecular profiling of peripheral tissues, including circulating leukocytes, may hold promise in the discovery of biomarkers for diagnosing and treating neurodegenerative diseases, including Alzheimer's disease (AD). As a proof-of-concept, we performed a proteomics study on peripheral leukocytes from patients with AD both before and during treatment with divalproex sodium. Using two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry, we identified 10 differentially expressed proteins: two up-regulated proteins, 14-3-3 protein epsilon and peroxiredoxin 2; and eight down-regulated proteins, actin-interacting protein, mitogen activated protein kinase 1, beta actin, annexin A1, glyceraldehyde 3-phosphate dehydrogenase, transforming protein RhoA, acidic leucine-rich nuclear phosphoprotein 32 family member B, and a currently unidentified protein. A subset was validated on both the transcript and protein levels in normal human peripheral blood mononuclear cell cultures treated with valproic acid. These proteins comprise a number of functional classes that may be important to the biology of AD and to the therapeutic action of valproate. These data also suggest the potential of using peripheral leukocytes to monitor pharmaceutical action for neurodegenerative diseases.