Objective: To explore the expression of uncoupling protein-2 mRNA in brown adipose tissue, white adipose tissue and skeletal muscle of diet-induced obesity-resistant (DIO-R) rats.
Methods: Fifty male Sprague-Dawley (SD) rats were randomly divided into a control group and a high-fat group and fed with basic diet and high-fat diet respectively for 13 weeks. DIO-R and DIO rats were selected according to their body weight. The change of body weight and the intake of total calorie were observed. Reverse transcription-polymerase chain reaction (RT-PCR) was used to measure the expression of UCP2 mRNA in rat.
Results: Body weight and total calorie intake in DIO-R rats (425.1 +/- 27.1) g, (31,693 +/- 946) kJ were significantly lower than those in DIO rats (489.7 +/- 20.5) g, (34,363 +/- 1465) kJ. The peak area of UCP2 mRNA in white adipose tissue in DIO-R rats was 352 +/- 30 and in DIO rats was 101 +/- 12. The peak areas of UCP2 mRNA in skeletal muscle in DIO-R and DIO rats were 130 +/- 15 and 170 +/- 12, respectively. The peak areas of UCP2 mRNA in brown adipose tissue of DIO and DIO-R rats were 124 +/- 14 and 147 +/- 19, respectively.
Conclusion: The expression of UCP2 mRNA in white adipose tissue of DIO-R rats increased significantly. These results suggest that obesity-resistance was associated with a tissue-specific increase in UCP2 expression.