title: [Prevention and treatment of age-related macular degeneration by extract of Fructus lycii and its constituents lutein/zeaxanthin: an in vive and in vitro experimental research].
abstract: OBJECTIVE
  To investigate the in vivo inhibition of extract of Fructus lycii (FL) on the expressions of cathepsin B (Cat B) and cystatin C (Cys C) in high-fat diet and hydroquinone (HQ) induced model mice with age-related macular degeneration (AMD), and to explore the in vitro effects of lutein and zeaxanthin on hydrogen peroxide (H2O2,) induced expressions of matrix metalloproteinase 2 (MMP-2) and tissue inhibitor of metalloproteinase 2 (TIMP-2) on ARPE-19 cells.
  
  
  METHODS
  Fifty female 8-month-old C57BL/6 mice were recruited in this research. Ten mice fed with regular diet was taken as the age control group. The rest 40 mice were fed with high fat diet for 6 months, followed by adding HQ (0. 8%) in the drinking water for 3 consecutive months. Then the modeled mice were randomly divided into the model control group (n =10), the high (at the daily dose of 3.75 g/kg), middle (at the daily dose of 2.50 g/kg), and low dose (at the daily dose of 1.25 g/kg) FL groups, 10 in each group. The extract of FL at each dose was respectively administered to mice by gastrogavage for 3 successive months. By the end of the experiment, the mice were killed and their eyeballs were removed. The protein expressions of Cat B and Cys C were observed by immunohistochemical assay. The mRNA and protein expressions of Cat B and Cys C were detected by real-time PCR and Western blot respectively. The drug concentrations of H2O2, lutein, and zeaxanthin were screened and detected using the activity of cell proliferation. The protein expressions of MMP-2 and TIMP-2 were detected using Western blot.
  
  
  RESULTS
  Compared with the age control group, the mRNA and protein expressions of Cat B and Cys C were significantly higher in the in vivo model control group (P <0.05, P <0.01). The mRNA expressions of Cat B and Cys C were weaker in the middle and high dose FL groups than in the model control group (P <0. 05, P <0. 01). In in vitro cells, lutein and zeaxanthin could down-regulate the protein expressions of MMP-2 and TIMP-2 in H202 induced ARPE-19 cells (P <0. 05, P <0. 01).
  
  
  CONCLUSIONS
  Extract of FL could down-regulate the high protein expressions of Cat B and Cys C in high-fat diet and HQ induced model mice. Lutein and zeaxanthin could down-regulate the protein expressions of MMP-2 and TIMP-2 in H202 induced ARPE-19 cells.
authors.affiliation: Nanjing University of Traditional Chinese Medicine, Nanjing, China.
authors.forename: Bing-Lin
authors.initials: BL
authors.lastname: Huang
authors.forename: Shu-Hua
authors.initials: SH
authors.lastname: Ding
authors.forename: Li
authors.initials: L
authors.lastname: Hang
authors.forename: Shi-Zhong
authors.initials: SZ
authors.lastname: Zheng
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Xin-rong
authors.initials: XR
authors.lastname: Xu
mesh_terms: D000818:Animals; D002401:Cathepsin B / Q000378:metabolism; D055316:Cystatin C / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005260:Female; D006861:Hydrogen Peroxide; D014975:Lutein / Q000494:pharmacology*; D008268:Macular Degeneration / Q000517:prevention & control*; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D010857:Pigment Epithelium of Eye / Q000187:drug effects / Q000378:metabolism; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism; D024341:Xanthophylls / Q000494:pharmacology*; D065146:Zeaxanthins
chemical_list: D055316:Cystatin C; D004365:Drugs, Chinese Herbal; D024341:Xanthophylls; D065146:Zeaxanthins; D019716:Tissue Inhibitor of Metalloproteinase-2; D006861:Hydrogen Peroxide; D002401:Cathepsin B; D020778:Matrix Metalloproteinase 2; C522362:Mmp2 protein, mouse; D014975:Lutein