Identification of low-molecular-weight protein (SCP1) from shark cartilage with anti-angiogenesis activity and sequence similarity to parvalbumin

Cartilage was considered as a possible natural source of anti-angiogenesis compounds due to its known avascular nature. In this study, a low-molecular-weight protein with an anti-angiogenesis activity was isolated from shark cartilage using a mild extraction procedure. The protein was purified to homogeneity by gel filtration and electroelution techniques and its N-terminal amino acid sequence was determined. The purified protein, designated as SCP1, represented a molecular weight of 13.7 kDa, pI of 6.9-7 and its N-terminal sequence revealed sequence similarity to alpha parvalbumin family. The protein inhibited angiogenesis when subjected to microvessel sprouting of collagen-embedded rat aortic ring assay. It is suggested that SCP1 could be considered as a new angiogenesis inhibitor derived from shark cartilage.