Phosphorylated peptides from Antarctic Krill (Euphausia superba ) improve fracture healing in mice with ovariectomy induced osteoporosis

Abstract

Open tibial fracture surgery was performed on ovariectomized mice to investigate the effect of phosphorylated peptides from Antarctic Krill (PP-AKP) on osteoporotic fracture healing. Dynamic histological analysis on days 11, 24, and 35 postsurgery showed that PP-AKP promoted hypertrophy and mineralization of cartilage callus, formation of new bone tissue, and remodeling of boney callus. Biomechanical property tests on day 35 postsurgery demonstrated that PP-AKP significantly improved callus stiffness. Real-time PCR analysis showed that on day 11 postsurgery, PP-AKP significantly decreased mRNA expression of aggrecan and collagen type X (Col10a), and increased vascular endothelial growth factor level, suggesting that it promoted chondrocytes hypertrophy and vascular invasion. On day 24 postsurgery, PP-AKP significantly decreased matrix metalloproteinase 13 expression, and increased expression of collagen type I and bone gla protein, suggesting that it promoted cartilage matrix degradation and new bone formation. Practical applications As a novel food material, Antarctic Krill possesses an enormous biomass (0.65–1 billion tons) and utilization potential. It has the largest amount of protein among reported organisms worldwide with better biological value than other animal proteins. This study demonstrated that phosphorylated peptides from Antarctic Krill could promote osteoporotic fracture healing on ovariectomized mice by facilitating endochondral ossification, which may provide theoretical basis for use of Antarctic Krill protein as bone protective functional food in future.