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Unuma H.,Yamagata University | Matsushima Y.,Yamagata University | Furusawa T.,Yamagata University | Sakai Y.,Jellice Co.
Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy | Year: 2016

Combination of two or more materials has been and can be a potential strategy to design and develop new biomaterials. For ages, glass ionomer cement and hydroxyapatite-coated titanium implants have been good examples. This article describes other new polymer-ceramic composite biomaterials which have been evidenced to show better efficacy; poly (ethylene terephthalate) coated with gelatin and low crystallinity hydroxyapatite for guided bone regeneration (PET membrane), calcium phosphate cement (CPC) with controlled setting behavior, and gelatin-coated β-TCP scaffold with enhanced mechanical strength and cytocompatibility. In vivo tests of PET membrane showed that the membrane promoted new bone formation, which was supported by in vitro tests evidencing the proliferation and calcification of osteoblasts on the PET membrane. Control of the setting behavior CPC has long been a challenge. The authors coated tetra calcium phosphate, one of the components of CPC, with gelatin because the setting liquid containing gelatin undergoes reversible sol-gel transition at a temperature between room temperature and body temperature. Gelled gelatin retards the setting reactions to proceed whereas gelatin sol does not hinder the reactions to take place. As the result, the CPC paste showed fluidity for 60 minutes at room temperature while set within 3 minutes at the body temperature. Reinforcement of porous β-TCP scaffolds has also been longed for. The authors coated porous β-TCP with gelatin, and prepared scaffolds with 92 % porosity and compressive strength of 5.1 MPa. The gelatin coating also improved in vivo cytocompatibility.

Tang L.,Kanazawa Medical University | Sakai Y.,Jellice Co. | Ueda Y.,Kanazawa Medical University | Katsuda S.,Kanazawa Medical University
Journal of Bioscience and Bioengineering | Year: 2015

Digestion of type I collagen with a collagenase-type protease yields a collagen tripeptide (Ctp) fraction comprising Gly-X-Y sequences that exhibit diverse biological activities. We previously demonstrated that Ctp inhibits the proliferation and migration of cultured aortic smooth muscle cells (SMCs) in vitro. These cells contribute to the pathogenesis of atherosclerosis and other cardiovascular diseases. In order to evaluate the effects of Ctp on atherosclerosis development in vivo, here we used the Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbit model of familial hypercholesterolemia to determine the effects of oral administration of Ctp for three months. Ctp induced a significant decrease in the area occupied by atherosclerotic plaques in the aorta and in the level of total serum cholesterol. The components of atherosclerotic plaques underwent distinct changes, including reduction in the populations of macrophages and SMCs and a significant decrease in the proportion of macrophages to SMCs. Ctp administration decreased the number of cells in plaques that expressed proliferating cell nuclear antigen and the number of cells with oxidative damage to DNA as indicated by 8-hydroxy-2'-deoxyguanine detection. These findings are the first to define the mechanism underlying the inhibitory effects of Ctp on atherosclerosis development in hypercholesterolemic rabbits, and suggest that Ctp provides an effective therapy for treating atherosclerosis. © 2014 The Society for Biotechnology, Japan.

Disclosed are a novel therapeutic agent and a novel prophylactic agent for atherosclerosis, a blood cholesterol level-lowering agent, and a functional food or a food for specified health uses effective for the inhibition and/or prevention of aging of blood vessels or inflammation in blood vessels. Specifically disclosed are an inhibitor of the progression of atherosclerosis, a prophylactic agent for atherosclerosis, a blood cholesterol level-lowering agent, and a functional food and a food for specified health uses both effective for the inhibition and/or prevention of aging of blood vessels or inflammation in blood vessels, each of which comprises, as an active ingredient, a hydrolysis product of a collagen comprising at least one collagen tripeptide Gly-X-Y [wherein Gly-X-Y represents an amino acid sequence; and X and Y independently represent an amino acid residue other than Gly].

Park J.,Yonsei University | Sakai Y.,Jellice Co. | Numata N.,Jellice Co. | Shin J.-Y.,Amore Pacific | And 3 more authors.
Preventive Nutrition and Food Science | Year: 2012

Collagen tripeptide (CTP) is a functional food material with several biological effects such as improving dry skin and wound and bone fracture healing. This study focused on the anti-photoaging effects of CTP on a hairless mouse model. To evaluate the effects of CTP on UVB-induced skin wrinkle formation in vivo, the hairless mice were exposed to UVB radiation with oral administration of CTP for 14 weeks. Compared with the untreated UVB control group, mice treated with CTP showed significantly reduced wrinkle formation, skin thickening, and transepidermal water loss (TEWL). Skin hydration and hydroxyproline were increased in the CTP-treated group. Moreover, oral administration of CTP prevented UVB-induced MMP-3 and -13 activities as well as MMP-2 and -9 expressions. Oral administration of CTP increased skin elasticity and decreased abnormal elastic fiber formation. Erythema was also decreased in the CTP-treated group. Taken together, these results strongly suggest that CTP has potential as an anti-photoaging agent. Copyright © 2012 Acil Ti{dotless}p Uzmanlari{dotless} Derneǧi.

Okawa T.,Yokohama City University | Yamaguchi Y.,Yokohama City University | Takada S.,Yokohama City University | Sakai Y.,Jellice Co. | And 5 more authors.
Journal of Dermatological Science | Year: 2012

Background: Dry skin causes pruritus and discomfort in patients with xerosis and atopic dermatitis. General treatment for skin dryness involves the topical application of an emollient. However, more effective, simpler therapies are desired. Collagen tripeptide (CTP) is a highly purified, non-antigenic, low-allergenic collagen fraction that is known to have various biological effects. Objective: To clarify the therapeutic effects of CTP for dry skin using acetone-induced dry skin model mice. Methods: ICR mice were treated with acetone followed by oral administration of CTP (80 or 500. mg/kg/day) for 3 days. Hyaluronic acid production induced by CTP was assessed using human dermal fibroblasts in vitro and in an acetone-induced dry skin model mice in vivo. Transepidermal water loss (TEWL) and scratching behavior were evaluated. Furthermore, the effects of CTP on intraepidermal nerve fibers and expression of semaphorin 3A (Sema3A) and nerve growth factor (NGF) were examined by immunohistochemistry and quantitative RT-PCR. Results: CTP enhanced hyaluronic acid production in human dermal fibroblasts in vitro and in murine skin in vivo. Oral administration of CTP in acetone-induced dry skin model mice significantly decreased TEWL and suppressed scratching behavior. Intraepidermal nerve growth was dramatically inhibited in CTP-treated mice. Quantitative PCR analysis and immunohistochemical study revealed that CTP abolished the increased NGF and decreased Sema3A levels induced by acetone treatment. Conclusion: Oral administration of CTP improves dry skin and normalizes axon-guidance factors in the epidermis in addition to reducing pruritus. CTP may be used in a new therapeutic strategy against dry skin and pruritus. © 2012 Japanese Society for Investigative Dermatology.

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