The goal of this study was to investigate the effects of vairous diets on the expression of genes involved in intermediary metabolism in liver. Adult wild type male mice (3 for each group) were fed with the corresponding diet for two weeks, and then liver samples were collected. Total RNA was isolated by the RNAzol B reagent, and pellet was disolved in DEPC-treated water. Total RNA was isolated using RNA Bee reagent (Tel-Test Inc., Friendswood, TX) per the manufacturers protocol. RNA concentrations were quantified using a NanoDrop Spectrophotometer (NanoDrop Technologies, Wilmington, DE) at a wavelength of 260 nm. The integrity of the total RNA samples was evaluated by formaldehyde-agarose gel electrophoresis, and confirmed by visualization of 18S and 28S rRNA bands. The gene expression was determined by Affymetrix Mouse 430 2.0 Gene Expression Microarray. Nine different diets were used: Diet 1. TD.84224. EFA Deficient diet; Diet 2. TD 97070. High fat diet: Diet 3. TD.88137. Adjusted Calories Diet (42% from fat) (Western Diet); Diet 4. TD.02028. Atherogenic Rodent Diet; Diet 5. TD.89247. 60% Fructose Diet; Diet 6. TD.94048. AIN-93M Purified Diet, Diet 7. Current rodent diet used in LAR; Diet 8. DHA-supplemented diet; Diet 9. Diet-restriction: 75% of the diet consumed by ad lib feeding. Mice (n=3/diet) were fed one of these diets (Harlan Laboratories) for 3 weeks. All mice were euthanized in the morning (8:0010:00 A.M.) and blood and tissue samples were collected. All procedures were approved in accordance with Institutional Animal Care and Use Committee guidelines.