Abstract: The aim of this study was to investigate the influence of auraptene (AUR) on food intake in mice and its mechanism. Mice were randomly divided to three groups including control group, 2 μmol/kg AUR group and 1 μmol/kg AUR group. AUR was continuously given by oral gavage for 2 weeks to measure the cumulative food intake of the mice, the expression of insulin-like growth factors (IGFs) in serum, liver and hypothalamus, insulin-like growth factor-binding proteins (IGFBPs) in liver, proopiomelanocortin (POMC) in hypothalamus. The levels of mRNA and protein of carnitine palmitoyltransferase 1A (CPT1A) as a peroxisome proliferator-activated receptor α (PPARα) target gene were also tested. The results showed that AUR promoted food intake in mice in a concentration-dependent manner, inhibited the expression of POMC (P<0.01), significantly promoted the expression of IGFBP-1 in liver (P<0.01), and significantly reduced the content of IGF-1 in serum and hypothalamus (P<0.01), but did not effect on IGF-1 in liver (P>0.05). Meanwhile, AUR significantly increased the expression of CPT1A in liver (P<0.01). In summary, these findings suggested that AUR could significantly promote food intake in mice. The main mechanism was that AUR promoted food intake in mice because of increasing the expression of IGFBP-1 in liver by PPARα activation, which bound the free IGF-1 in serum to decrease IGF-1 in hypothalamus and inhibit the expression of POMC.

Key words: auraptene, food intake, insulin-like growth factor-binding proteins, peroxisome proliferator-activated receptor α, liver, brain