Uric Acid-Lowering Activity in Vitro and in Vivo and Mechanism of Sheep Bone Bioactive Peptides

Sheep bone bioactive peptides (SBBP) were prepared by successive enzymatic hydrolysis of sheep bones by alkaline and neutral proteases. This study evaluated the structure, amino acid composition, molecular mass distribution, and xanthine oxidase inhibitory activity of SBBP. The results showed that successive enzymatic hydrolysis altered the secondary structure of sheep bone proteins. SBBP were rich in hydrophobic, aromatic, and basic amino acids. Peptides with a molecular mass less than 1 000 Da accounted for 94.48% of SBBP. SBBP exhibited xanthine oxidase inhibitory activity in vitro, with a half maximal inhibitory concentration (IC50) of 14.27 mg/mL. In a hyperuricemic mouse model, SBBP significantly reduced serum uric acid, creatinine and urea nitrogen levels by inhibiting the activity of xanthine oxidase and adenosine deaminase, and alleviated kidney damage. This study indicates that SBBP holds the potential for preventing and alleviating hyperuricemia.