Interaction between curcumin and a peptide and their protective effects against hepatic steatosis in mice Interaction and liver protection of curcumin and peptide

Abstract Curcumin is antioxidative, liver protective and it has lipid regulatory effects. However, its in vivo efficiency is limited because of the low absorption rate and bioavailability. LVYP (Leu-Val-Tyr-Pro) is a tetrapeptide isolated, purified and identified from Corbicula fluminea with strong antioxidant activity. The interaction mechanisms between curcumin and LVYP were investigated using UV–vis absorption and fluorescence spectra. The results showed that the interaction between curcumin and LVYP was hydrophobic. When the temperature was increased from 25 to 37°C, ΔG decreased and the number of ligand molecules increased, the interaction was quenched statically explained the formation of some compounds. On the other hand, dynamic quenching occurred when the temperature reached 60°C, ΔG increased and the number of ligand molecules decreased, which indicated that temperature affected the interaction between curcumin and LVYP. This study also showed that LVYP could promote intestinal absorption of curcumin, predominantly in the ileum, which was explored using a non-everted intestinal sac model. In vivo experiments showed that the liver’s protective effect with the combined administration of LVYP and curcumin was better than the curcumin alone, and LVYP could promote the hepatoprotective function of curcumin. It was hypothesized that the interaction of LVYP and curcumin enhanced the intestinal absorption rate of curcumin, thereby increasing its liver protection effect.