Identification of bio-active collagen type II alpha 1 protein in shark cartilage (181.3)

Abstract

Abstract Previous studies have shown that extracts of shark cartilage (SC) induce a significant cytokine response in human leukocytes characteristic of a Th1 immune response. The nature of the bio-active component(s), however, is unknown. The aim of the present study was to identify the bio-active component(s) in SC. Cartilage extracts treated with proteases lost 80% of their cytokine-inducing property, suggesting that the active component(s) was likely a complex protein. Employing a protocol involving acid and solid phase extraction followed by ion exchange chromatography and electrophoretic separation, a partially purified bio-active preparation was obtained from commercial shark cartilage. At least two cytokine-inducing components were separated chromatographically and an anionic fraction has been identified as a small glycoprotein with at least 40% carbohydrate content. LC-MS analysis yielded five unique peptides with 100% molecular identity with collagen type II, alpha 1 protein from the lesser spotted catshark, Scyliorhinus canicula. The presence of collagen type II, alpha 1 protein in a dietary supplement has significant health implications given its role in the pathology associated with arthritis. Our findings suggest that consumers of SC, taken as prophylaxis particularly for the maintenance of joint health, should be cautious of the potential unanticipated immunomodulatory activity associated with peptides present in commercial preparations.