Transcription profiling of rat epididymal fat tissues from diet induced obesity model against lean controls

ABSTRACT: Analysis of gene expression profiles of epididymal fat from DIO rats; We applied a comparative functional genomics approach to evaluate diet-induced obese (DIO) rats as an obesity model Experiment Overall Design: Gene expression profiles from DIO and lean rats were generated and compared. A private colony of male Long-Evans rats was set up at Harlan (Harlan-Sprague Dawley, Indianapolis, IN). The animals had been on either a high fat/high sucrose diet (TD95217, Harlan Takled, Madison, WI) or a regular chow (Purina 5008; Ralston-Purina, St. Louis, MO) since weaning. Rats were shipped at 14-weeks of age to our facility and maintained on a 12:12-hour light-dark photoperiod (light on 10:00 PM). They were individually housed throughout the study at ambient temperature, and had free access to diets and water. After 2 weeks acclimation to the facility, body weight of the rats and weight of food consumed in the last 7 days were measured once a week. Body fat mass was analyzed by nuclear magnetic resonance (NMR) using an Echo Medical System (Houston, TX) instrument 3 times throughout the study. Fat free mass is the difference between body mass and fat mass. All animal studies were conducted in compliance with approved institutional animal care and use protocols according to NIH guidelines (NIH publication No. 86-23, 1985). OGTT was conducted after an overnight fasting when animals were 21 weeks of age. After a baseline blood collection (time 0), animals were dosed orally with 1.5 gram/kg glucose. Subsequence blood samples were collected at 30, 60, and 120 minutes post glucose challenge for the determination of plasma glucose and insulin levels. At 25 weeks of age, blood was collected by tail bleeding after overnight fasting. Rats were killed a week later at 09:00am by rapid decapitation. Trunk blood was collected and epididymal fat tissue excised. Various circulating metabolic parameters were measured under fasted (week 25) and fed conditions (week 26). Total RNA from rat epididymal fat was isolated with RNA STAT-60 (Tel-Test) according to the manufacturer's protocol. 5 micrograms of total RNA were labeled and hybridized to Affymetrix RAE230_2 arrays according to the Affymetrix protocol.

ORGANISM(S): Rattus norvegicus

SUBMITTER: Dan Li 

PROVIDER: E-GEOD-8700 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress