Effect of Marine Collagen Peptide on Skin Condition

Abstract

Collagen is defined as proteinous components with a triple helical structure in the extracellular matrix. Collagen forms a family consisting of closely related but different gene products and divided into two groups: fibrillar and nonfibrillar collagens (van der Rest and Garrone, 1991; Heino, 2007). In mammalian and avian tissues, the fibrillar collagen includes type I, II, III, V, and XI collagens (Sato et al., 1989; Zylberberg et al., 1992). Type I and II collagens are major constituents in skin, bone, tendon (type I), and cartilage (type II) in vertebrates, including fish, and type V collagen is codistributed with type I collagen as minor components in fish (Sato et al., 1989). In cartilage, type XI collagen is codistributed with type II collagen (Kelly et al., 1988). Thus, type I and II collagens are mainly used for collagen-related food ingredients. The collagens specifically consist of hydroxyproline (Hyp) and hydroxylysine (Hyl), posttranslational modified amino acids of proline (Pro) and lysine (Lys), respectively. The triple helical domain of the fibrillar collagen has a Gly-X-Y repeating motif, where X and Y are frequently occupied by Pro and Hyp, respectively (van der Rest and Garrone, 1991). The triple helical structure will be lost by heating the solution and converted into a globular structure. The denatured form of collagen is referred to as gelatin, which can be dissolved in hot water, yielding a viscous solution, and gel formation occurs by cooling the gelatin solution. Gelatin has long been used as a food ingredient as well as in folk medicine in Asia to improve blood circulation and arrest bleeding (Yao et al., 1989). In Western countries, gelatin consumption has been believed to improve joint condition by reducing pain (Moskowitz, 2000). Recently, partially hydrolyzed gelatin products have been prepared by enzymatic hydrolysis in order to increase their solubility in cold water. These are referred to as collagen peptides, and in some cases, simply as collagen in commercial products. Large amounts of collagen peptide preparations have been obtained from bone and skin of cattle, pig, chicken, etc. However, after the prevalence of bovine spongiform encephalopathy, much interest has been focused on production of collagen peptides from fish scales, skin, bone, etc. Episodes suggesting that ingestion of the collagen peptide would improve subjective skin conditions are widely prevalent in Japan and other countries. In Japan, annual sales of collagen peptide as a food supplement reached approximately US$300 million in 2007. Recent human CONTENTS