title: The influences of purple sweet potato anthocyanin on the growth characteristics of human retinal pigment epithelial cells.
abstract: BACKGROUND
  Anthocyanins have been proven to be beneficial to the eyes. However, information is scarce about the effects of purple sweet potato (Ipomoea batatas, L.) anthocyanin (PSPA), a class of anthocyanins derived from purple sweet potato roots, on visual health.
  
  
  OBJECTIVE
  The aim of this study was to investigate whether PSPA could have influences on the growth characteristics (cellular morphology, survival, and proliferation) of human retinal pigment epithelial (RPE) cells, which perform essential functions for the visual process.
  
  
  METHODS
  The RPE cell line D407 was used in the present study. The cytotoxicity of PSPA was assessed by MTT assay. Then, cellular morphology, viability, cell cycle, Ki67expression, and PI3K/MAPK activation of RPE cells treated with PSPA were determined.
  
  
  RESULTS
  PSPA exhibited dose-dependent promotion of RPE cell proliferation at concentrations ranging from 10 to 1,000 µg/ml. RPE cells treated with PSPA demonstrated a predominantly polygonal morphology in a mosaic arrangement, and colony-like cells displayed numerous short apical microvilli and typical ultrastructure. PSPA treatment also resulted in a better platform growing status, statistically higher viability, an increase in the S-phase, and more Ki67+ cells. However, neither pAkt nor pERK were detected in either group.
  
  
  CONCLUSIONS
  We found that PSPA maintained high cell viability, boosted DNA synthesis, and preserved a high percentage of continuously cycling cells to promote cell survival and division without changing cell morphology. This paper lays the foundation for further research about the damage-protective activities of PSPA on RPE cells or human vision.
authors.affiliation: Key Laboratory of Food Nutrition and Safety of the Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin, China.
authors.forename: Min
authors.initials: M
authors.lastname: Sun
authors.affiliation: Key Laboratory of Food Nutrition and Safety of the Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin, China; lu_xiaoling@sina.com.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Lu
authors.affiliation: Key Laboratory of Food Nutrition and Safety of the Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Hao
authors.affiliation: Key Laboratory of Food Nutrition and Safety of the Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.affiliation: Key Laboratory of Food Nutrition and Safety of the Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin, China.
authors.forename: Huanjiao
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Food Nutrition and Safety of the Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
keywords: PSPA; RPE cells; morphology; proliferation; survival