Effect Of Collagen From Tilapia Skin On Delaying Skin Aging In Chronologically Aged Mice

Collagen has been applied to delay skin aging for a long history with various forms.However,since it lacked for enough theoretical basis,the application of collagen still existed blindness and in result of the doubt of people and the mess in the markrt.In this parer,the effect of oral administration of collagen with different doses,sources and molecular weight in chronologically aged mice was systematically investigated,so that it could evaluate the efficacy of collagen and provide new theoretical basis for its application in delaying skin aging.The nine-month healthy female ICR mouse(38 ± 4 g)were fed with diet added collagen with different doses(2.5%,5%,10%),sources(fish skin,chicken feet,pig skin)and molecular weight(high,middle,low).After 6 months,the physic-chemical properties,oxidative stress of skin,the distribution of skin tissue and collagen fibers of skin were observed,the results were as follows:1.The oral administration of collagen with 5% could significantly reduce the body weight and food intake,increase the content of collagen in skin.Moreover,it were obviously improved the visual appearance,histological structure and enhanced the activities of superoxide dismutase and glutathione peroxidase in the chronologically aged skin.However,the oral administration of collagen with 2.5% had no significantly influence on the content of collagen and the activity of antioxidant enzymes in skin.In addition,the oral administration of collagen with 10% could cause the swell of viscera,and it had toxicity,side effects and high mortality.Therefore,the 5% of collagen was the best dose in delaying skin aging.2.The oral administration of collagen from fish,chicken and pig could significantly increase the elasticity and the thickness of the dermis in the skin,and balance the ratio of collagen types III and I.It could also improve the visual appearance and histological structure,and improve the total antioxidant capacity,the activity of catalase,superoxide dismutase and glutathione peroxidase of the skin.However,the oral administration of collagen from chicken could not significantly influence the content of collagen and water in the skin of mice.Although the effect of oral administration of collagen from pig on delaying skin aging was similar to it from fish,the content of fat of pig skin was higher than fish.Moreover,the collagen from fish has higher bio-safety,so it was the optimum source for collagen to delay skin aging.3.The oral administration of collagen with high,middle and low molecular weight could significantly improve the content of collagen,elasticity,and balance the ratio of collagen types III and I.It could also improve the histological structure,and improve the antioxidant enzyme(catalase,superoxide dismutase,glutathione peroxidase)activities of the skin.However,the oral administration of collagen with low molecular weight had no significantly influence on the thickness of the dermis and the total antioxidant capacity of the skin.The oral administration of collagen with high molecular weight had negative effect on visceral index,and had no significantly influence on the thickness of the dermis and the ratio of collagen types III and I.Therefore,the collagen with middle molecular weight was the optimum in term of the effect on delaying skin aging.