Actions of acidic fibroblast growth factor fragments on food intake in rats

Acidic fibroblast growth factor (aFGF) has suppressive effects on food intake. In the present study, the effect of aFGF fragments on food intake were investigated in rats. Infusion of a carboxyl-terminal fragment of aFGF, aFGF-(114-140), did not affect food intake, whereas an amino-terminal fragment of aFGF, aFGF-(1-15), was significantly inhibitory. Other amino-terminal fragments, aFGF-(1-20), aFGF-(1-29) and aFGF-(9-29), did not affect food intake. However, [Ala16]aFGF-(1-29) and [Ser16]aFGF-(1-29) in which the cysteine residue at position 16 was replaced with alanine and serine, respectively, had significant suppressive effects on food intake. Infusion of a functional antagonist for FGF receptor, anti-FGFR-1 antibody, into the lateral hypothalamus (LHA) significantly increased food intake. The results suggest that: the amino-terminal portion of aFGF is active in food intake suppression; the replacement of cysteine residue by alanine or serine is important in some amino-terminal aFGF fragments; and the LHA is involved in feeding suppression actions by aFGF and some fragments.