title: Constituents in purple sweet potato leaves inhibit in vitro angiogenesis with opposite effects ex vivo.
abstract: OBJECTIVE
  The aim of this study was to investigate the in vitro effect of polyphenols in purple sweet potato leaves (PSPLs) on angiogenesis in human umbilical vascular endothelial cells (HUVECs). The ex vivo effect was test in human serum collected from the subjects who consumed 200 g of PSPL in a low polyphenol diet versus a low polyphenol diet.
  
  
  METHODS
  Methanolic extract from PSPLs and human sera from subjects were treated with HUVECs and the effects of cell proliferation, migration, tube formation, and matrix metalloproteinase activity were investigated.
  
  
  RESULTS
  The PSPL polyphenols at 0.2 to 0.6 mM gallic acid equivalents inhibited proliferation, migration, and tube formation of vascular endothelial growth factor-treated HUVECs. Further, the activity of secreted matrix metalloproteinase-2 was decreased by at least 13.8%. However, 5% PSPL serum increased migration and tube formation of HUVECs by 110% and 56.9%, respectively, compared with serum from subjects on the low polyphenol diet. Further, the activity of matrix metalloproteinase-9 was increased by 128% in the PSPL serum.
  
  
  CONCLUSIONS
  These results suggest that PSPL polyphenols inhibited in vitro angiogenesis, but PSPL constituents might shift serum biochemistries to be more proangiogenic.
authors.affiliation: Department of Food Science, Nutrition and Nutraceutical Biotechnology, Shih Chien University, Taipei, Taiwan, ROC.
authors.forename: Chiao-Ming
authors.initials: CM
authors.lastname: Chen
authors.forename: Sing-Chung
authors.initials: SC
authors.lastname: Li
authors.forename: C-Y Oliver
authors.initials: CY
authors.lastname: Chen
authors.forename: Heng-Kien
authors.initials: HK
authors.lastname: Au
authors.forename: Chun-Kuang
authors.initials: CK
authors.lastname: Shih
authors.forename: Ching-Yun
authors.initials: CY
authors.lastname: Hsu
authors.forename: Jen-Fang
authors.initials: JF
authors.lastname: Liu
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D018592:Cross-Over Studies; D005260:Female; D005707:Gallic Acid; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D027723:Ipomoea batatas / Q000737:chemistry*; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000187:drug effects / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000187:drug effects / Q000378:metabolism; D018919:Neovascularization, Physiologic; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry*; D059808:Polyphenols / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D059808:Polyphenols; D005707:Gallic Acid; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9