title: Pigment epithelium-derived factor prevents advanced glycation end products-induced monocyte chemoattractant protein-1 production in microvascular endothelial cells by suppressing intracellular reactive oxygen species generation.
abstract: OBJECTIVE
  Monocytes and macrophages accumulate in the lesion of the diabetic retina, which are most likely involved in the progression of diabetic retinopathy. The levels of monocyte chemoattractant protein-1 (MCP-1) in vitreous fluids were associated with the severity of proliferative diabetic retinopathy. Recently, pigment epithelium-derived factor has been shown to be involved in the pathogenesis of proliferative diabetic retinopathy. However, a role of pigment epithelium-derived factor in monocyte recruitments in diabetic retinopathy remains to be elucidated. In this study, we investigated effects of purified pigment epithelium-derived factor on AGE-induced reactive oxygen species generation, MCP-1 mRNA up-regulation and protein production in human cultured microvascular endothelial cells.
  
  
  METHODS
  The intracellular formation of reactive oxygen species was measured using the fluorescent probe CM-H(2)DCFDA. MCP-1 gene expression was analysed in quantitative reverse transcription-polymerase chain reaction. Monocyte chemoattractant protein-1 production by microvascular endothelial cells was measured with an ELISA system.
  
  
  RESULTS
  AGE increased intracellular reactive oxygen species generation in microvascular endothelial cells. Pigment epithelium-derived factor inhibited the AGE-induced reactive oxygen species generation in a dose-dependent manner. An anti-oxidant, N-acetylcysteine, or pigment epithelium-derived factor completely prevented the AGE-induced up-regulation of MCP-1 mRNA contents as well as protein production in microvascular endothelial cells.
  
  
  CONCLUSIONS
  Pigment epithelium-derived factor inhibits the AGE-induced reactive oxygen species generation and the subsequent increase in MCP-1 production in microvascular endothelial cells. Our study suggests that substitution of pigment epithelium-derived factor could prevent the progression of diabetic retinopathy by attenuating the deleterious effects of AGE.
authors.affiliation: Division of Endocrinology and Metabolism, Kurume University School of Medicine, Kurume 830-0011, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Inagaki
authors.forename: S
authors.initials: S
authors.lastname: Yamagishi
authors.forename: T
authors.initials: T
authors.lastname: Okamoto
authors.forename: M
authors.initials: M
authors.lastname: Takeuchi
authors.forename: S
authors.initials: S
authors.lastname: Amano
mesh_terms: D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005136:Eye Proteins; D015870:Gene Expression / Q000187:drug effects; D017127:Glycation End Products, Advanced / Q000494:pharmacology*; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism*; D009414:Nerve Growth Factors; D011506:Proteins / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors*; D015843:Serpins / Q000494:pharmacology*; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D018932:Chemokine CCL2; D005136:Eye Proteins; D017127:Glycation End Products, Advanced; D009414:Nerve Growth Factors; D011506:Proteins; D017382:Reactive Oxygen Species; D015843:Serpins; D000099174:Pigment Epithelium-Derived Factor