Intracranial administration of transforming growth factor-beta3 increases fat oxidation in rats.
The effects of intracranial transforming growth factor (TGF)-beta3 on spontaneous motor activity and energy metabolism were examined in rats. After injection of TGF-beta3 into the cisterna magna of the rat, spontaneous motor activity decreased significantly for 1 h. The intracranial injection of TGF-beta3 produced an immediate decrease in respiratory exchange ratio (RER). No significant changes were observed in energy expenditure. TGF-beta3 induced a significant increase in total fat oxidation and a decrease in total carbohydrate oxidation. Furthermore, the serum substrates associated with fat metabolism were significantly altered in rats injected with TGF-beta3. Both lipoprotein lipase activity in skeletal muscle and the concentration of serum ketone bodies increased, suggesting that the increase in fat oxidation caused by TGF-beta3 may have occurred in the liver and muscle. Intracranial injection of TGF-beta3 appeared to evoke a switch in the energy substrates accessed in energy expenditure. These results suggest that the release of TGF-beta3 in the brain by exercise is a signal for regulating energy consumption.
Yamazaki
Hanae
H
Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
Arai
Masanao
M
Matsumura
Shigenobu
S
Inoue
Kazuo
K
Fushiki
Tohru
T
D000818:Animals; D001769:Blood / Q000378:metabolism; D002946:Cisterna Magna; D004734:Energy Metabolism / Q000187:drug effects; D005223:Fats / Q000378:metabolism*; D005990:Glycerol / Q000097:blood; D006728:Hormones / Q000097:blood; D007267:Injections; D008071:Lipoprotein Lipase / Q000378:metabolism; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D018482:Muscle, Skeletal / Q000201:enzymology; D010084:Oxidation-Reduction / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000008:administration & dosage* / Q000494:pharmacology; D053782:Transforming Growth Factor beta3
D005223:Fats; D006728:Hormones; C509046:Tgfb3 protein, rat; D016212:Transforming Growth Factor beta; D053782:Transforming Growth Factor beta3; D008071:Lipoprotein Lipase; D005990:Glycerol