We have previously reported that the concentration of transforming growth factor-β (TGF-β) increases in the cerebrospinal fluid of rats during exercise and that there is an increase in whole body fat oxidation following the intracisternal administration of TGF-β. These results led us to postulate that TGF-β in the brain regulates the enhancement of fatty acid oxidation during exercise. To test this hypothesis, we carried out respiratory gas analysis during treadmill running following the inhibition of TGF-β activity in rat brain by intracisternal administration of anti-TGF-β antibody or SB-431542, an inhibitor of the type 1 TGF-β receptor. We found that each reagent partially blocked the increase in the fatty acid oxidation. We also compared the plasma concentrations of energy substrates in the group administered anti-TGF-β antibody and the control group during running. We found that the plasma concentrations of nonesterified fatty acids and ketone bodies in the group administered anti-TGF-β antibody were lower than in the control group at the end of running. In the same way, we carried out respiratory gas analysis during treadmill running after depressing corticotropin-releasing factor activity in the brain using intracisternal administration of astressin, an inhibitor of the corticotropin-releasing factor receptor. However, there were no significant differences in respiratory exchange ratio or oxygen consumption in moderate running (60% maximum oxygen consumption). These results suggest that brain TGF-β has a role in enhancing fatty acid oxidation during endurance exercise and that this regulation is executed at least partly via the type 1 TGF-β receptor signal transduction system.
|Journal||American Journal of Physiology - Endocrinology and Metabolism|
|Publication status||Published - 2006|
All Science Journal Classification (ASJC) codes
- Endocrinology, Diabetes and Metabolism
- Physiology (medical)