Background: Obesity has become a global epidemic and contributes to the increasing burden of type 2 diabetes, cardiovascular disease and some cancers worldwide. However, the precise molecular mechanisms of obesity remain poorly elucidated. Recent data indicate monitoring of brain energy status especially in the hypothalamus, is crucial for energy homeostasis. Anti-oxidant defenses are suggested to play an important role in production of a well-balanced signal, which is necessary for adjusted neuronal activities.
Material/Methods: Hypothalamus proteomes of the diet-induced obesity (DIO) and diet-resistant (DR) rats were analyzed using 2-dimensional gel electrophoresis (2-DE) combined with MALDI-TOF/TOF-MS analysis.
Results: The 2-DE maps showed a resolution of 1280±15, 1250±10, 1260±12 protein spots in normal, DIO and DR groups, respectively. Twenty-two proteins were identified in the hypothalamus of DIO or DR rats. These proteins are involved in metabolism enzymes, antioxidant proteins, proteasome-related proteins and signaling proteins. In comparison with normal-diet group, peroxiredoxin1 (Prx1) was significantly decreased in DR group and it was increased in DIO group. The expression of Prx1 was further validated by Western blot analysis.
Conclusions: The differential expression of Prx1 in DR and DIO groups indicated that the antioxidant protein may play an important role in the genesis of DR or DIO. This study provides new clues to illuminate the mechanisms involved in the progress of DIO and DR in the hypothalamus.

Keywords: Obesity - metabolism, Proteins - metabolism, Motor Activity - physiology, Hypothalamus - metabolism, Homeodomain Proteins - metabolism, Diet, Random Allocation