title: [Effects of marine collagen peptide on delaying the skin aging].
abstract: OBJECTIVE
  To investigate the protective effect of marine collagen peptides (MCPs) on the skin of aged mice induced by D-galactose.
  
  
  METHODS
  Subchronic toxicity study was conducted while D-galactose induced subacute aging model was established. D-galactose dose of 0.125 g/kg body weight was intraperitoneally injected daily for 90 days. Marine collagen peptide 0.225, 0.450, 1.350 g/kg body weight were administered by oral gavage. Superoxide dismutase (SOD), catalase (CAT) activity and malondialdehyde (MDA) content in blood serum were measured, along with cutaneous histopathology examination.
  
  
  RESULTS
  Epidermal thickness was significantly higher in MCPs treated group. Number and activity of fibroblast in MCPs treated dermis was increased prominently. The activity of SOD in 0.225, 0.450, 1.350 g/kgbw MCPs treated groups were 455.52 +/- 11.39, 460.15 +/- 18.09, 468.59 +/- 27.25 U/ml respectively, each of which was significantly higher than that in model control group; the activity of serum CAT in 0.225, 1.350 g/kgbw MCPs treated groups (21.33 +/- 4.82, 21.69 +/- 1.68 U/ml) were obviously increased compared with that in model control group (17.14 +/- 2.81 U/ml); MDA level in 0.450, 1.350 g/kgbw MCPs treated groups were 5.67 +/- 0.93, 5.76 +/- 1.02 nmol/ml respectively, each of which was significantly lower than that in model control group (7.63 +/- 1.37 nmol/ml).
  
  
  CONCLUSIONS
  The results showed that MCPs might play a protective role on skin aging by improving the activity of antioxidant.
authors.affiliation: Department of Food and Nutritional Hygiene, School of Public Health, Beijing University, Beijing 100083, China.
authors.forename: Xin-rong
authors.initials: XR
authors.lastname: Pei
authors.forename: Rui-yue
authors.initials: RY
authors.lastname: Yang
authors.forename: Zhao-feng
authors.initials: ZF
authors.lastname: Zhang
authors.forename: Ya-jun
authors.initials: YJ
authors.lastname: Xu
authors.forename: Xiao-long
authors.initials: XL
authors.lastname: Han
authors.forename: Jun-bo
authors.initials: JB
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Li