title: Chlorogenic acid decreases retinal vascular hyperpermeability in diabetic rat model.
abstract: To evaluate the effect of chlorogenic acid (CGA), a polyphenol abundant in coffee, on retinal vascular leakage in the rat model of diabetic retinopathy, Sprague-Dawley rats were divided into four groups: controls, streptozotocin-induced diabetic rats, and diabetic rats treated with 10 and 20 mg/kg chlorogenic acid intraperitoneally daily for 14 days, respectively. Blood-retinal barrier (BRB) breakdown was evaluated using FITC-dextran. Vascular endothelial growth factor (VEGF) distribution and expression level was evaluated with immunohistochemistry and Western blot analysis. Expression of tight junction proteins, occludin and claudin-5, and zonula occludens protein, ZO-1 was also evaluated with immunohistochemistry and Western blot analysis. BRB breakdown and increased vascular leakage was found in diabetic rats, with increased VEGF expression and down-regulation of occludin, claudin-5, and ZO-1. CGA treatment effectively preserved the expression of occludin, and decreased VEGF levels, leading to less BRB breakdown and less vascular leakage. CGA may have a preventive role in BRB breakdown in diabetic retinopathy by preserving tight junction protein levels and low VEGF levels.
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Shin
authors.forename: Joonhong
authors.initials: J
authors.lastname: Sohn
authors.forename: Kyu Hyung
authors.initials: KH
authors.lastname: Park
mesh_terms: D000818:Animals; D001813:Blood-Retinal Barrier / Q000187:drug effects*; D002726:Chlorogenic Acid / Q000378:metabolism / Q000494:pharmacology*; D062507:Claudin-5 / Q000378:metabolism; D003911:Dextrans / Q000737:chemistry; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D003930:Diabetic Retinopathy / Q000209:etiology / Q000517:prevention & control; D015536:Down-Regulation; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D008297:Male; D062793:Occludin / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism*; D062725:Tight Junction Proteins / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D062826:Zonula Occludens-1 Protein / Q000378:metabolism
chemical_list: D062507:Claudin-5; D003911:Dextrans; D062793:Occludin; D062725:Tight Junction Proteins; C569044:Tjp1 protein, rat; D042461:Vascular Endothelial Growth Factor A; D062826:Zonula Occludens-1 Protein; D002726:Chlorogenic Acid; D016650:Fluorescein-5-isothiocyanate
keywords: Blood-Retinal Barrier; Chlorogenic Acid; Diabetes Rat Model; Diabetic Retinopathy; Vascular Endothelial Growth Factor