Effects of Ingestion of Collagen Peptide on Collagen Fibrils and Glycosaminoglycans in the Dermis

Abstract

Summary In order to investigate the effects of collagen peptide ingestion on fibroblasts and the extracellular matrix in the dermis, collagen peptide was administered orally to pigs at 0.2 g/kg body weight/d for 62 d, and its effects were compared with those of lactalbumin and water controls. Fibroblast density, and diameter and density of collagen fibrils were significantly larger in the collagen peptide group than in the lactalbumin and water control groups. The two major components of dermal glycosaminoglycans, hyaluronic acid and dermatan sulfate, which are present in the inter-fibrillar space, did not differ significantly among the three groups. However, the ratio of dermatan sulfate, which is derived from fibrilbound decorin, was largest in the collagen peptide group. These results suggest that ingestion of collagen peptide induces increased fibroblast density and enhances formation of collagen fibrils in the dermis in a protein-specific manner. Key Words collagen peptide, dermis, collagen fibril, glycosaminoglycan, electron microscopyThe skin is the largest organ in the human body and protects the body from various external insults. Skin comprises two layers, the epidermis and the dermis, consisting of stratified squamous epithelium and connective tissues, respectively. The dermis contains large amounts of extracellular matrix (ECM) components, such as collagen and glycosaminoglycans (GAG), mainly produced by fibroblasts ( 1 ). Collagen is the most abundant protein in the vertebrate body, comprising approximately 30% of the total protein. To date, over 20 types of collagen genes have been identified, and these are divided into three groups: fibrous collagen, fibrilassociated collagen and basement membrane collagen ( 2 ). In the dermis, type I collagen forms collagen fibrils that are further organized into collagen fibers in association with other types of fibrous or fibril-associated collagen ( 3 ). The size of collagen fibrils is an important factor that determines the physical nature of tissue, as collagen fibrils/fibers form the framework of the vertebrate body ( 4 ). The size of collagen fibrils varies depending on tissue type and physiological conditions ( 5 ). Their diameters are reportedly regulated, for example, by the content of collagen types III or V or other types of non-fibrous collagen. Rates of synthesis and degradation of collagen also probably determine the size of collagen fibrils ( 6 , 7 ).GAG consists of repeating two-sugar units and, with the exception of hyarulonic acid (HA), exists in tissue as proteoglycans that form covalent bonds with core proteins ( 8 ). The dermatan sulfate (DS) proteoglycan decorin is located on the surface of collagen fibrils and regulates their size ( 9 ). On the other hand, HA is highly hydrophilic and forms a gel with large amounts of water, playing a role in resisting external mechanical stresses ( 8 , 10 ). The change in the ratio of HA affects the diameter of the collagen fibrils ( 11 ). Thus, the size of collagen fibrils and the amount of GAG, such as ...

An Overview of the Beneficial Effects of Hydrolysed Collagen as a Nutraceutical on Skin Properties: Scientific Background and Clinical Studies

“…Collagen is the major insoluble fibrous protein found in the extracellular matrix of the skin, together with elastin and hyaluronic acid. The collagen family consists of 28 different proteins [1,2], which account for 25% -35% of the total protein mass in mammals and play a pivotal role in the structure of several tissues, such as skin and bones, providing rigidity and integrity *Address correspondence to the author at the 1-6 Yarmouth Place, London, W1J 7BU, United Kingdom; Tel: +44(0)7805064508; E-mail: ssibilla@minervalabs.com [3,4]. The extracellular matrix (ECM) of connective tissues is formed by diverse protein families involved in the structural integrity and several physiological functions.…”

“…Based on their structure and three-dimensional organization, the collagen family of proteins can be grouped into fibril-forming collagens, fibril-associated collagens (FACIT), network-forming collagens, anchoring fibrils, transmembrane collagens (MACIT), basement membrane collagens and others with unique functions [2,5].…”

Effects of Collagen Peptide Ingestion on Blood Lipids in Rats Fed a High-Lipid and High-Sucrose Diet

“…For example, gelatin ingestion results in increased bone mineral density and bone strength (Koyama et al, 2001;Wu et al, 2004). Meanwhile, CP supplementation increases the diameter and density of collagen fibrils, the major components of the dermis and tendons (Minaguchi et al, 2005;Matsuda et al, 2006), and the effects of CP are superior to those of lactalbumin for increasing bone mineral density (Koyama et al, 2001).…”

Effects of Collagen-Derived Oligopeptide Prolylhydroxyproline on Differentiation of Mouse 3T3-L1 Preadipocytes

“…For example, ingestion of CP decreases joint pain in athletes (Clark et al, 2008) and increases bone mineral density in animals experiencing protein malnutrition (Koyama et al, 2001). CP ingestion also improves the mechanical properties of the Achilles tendon (Minaguchi et al, 2005) and the skin (Matsuda et al, 2006). Skin damage induced by repeated UVB irradiation in mice is suppressed by CP ingestion (Tanaka et al, 2009).…”