Verification of array data. A, B and C. 6-month old APP23 animals were treated with T0 for 25 days at a dose of 50 mg/kg/day (n = 5); control mice (n = 5) received vehicle and gene expression profiles were generated using Affymetrix 430A 2.0 mouse gene chips. RT-QPCR for selected up-regulated (A and B) and down-regulated (C) genes from T0-treated and control mice was performed on the same total RNA as used for the array assays and the results compared to those from the array experiments. Fold changes observed in arrays (white bars) and RT-QPCR (grey bars) for each gene tested are arranged adjacently (± S.E.M.) and were statistically significant (p < 0.05 using two-tailed Student's t test). D. 6–7 month old APP23 animals were treated for 24 hours with T0 (50 mg/kg body weight, n = 5); control mice (n = 5) received vehicle. Total RNA was extracted from homogenized cortices and hippocampi and the expression of selected LXR target genes was determined by RT-QPCR.