Protective effects of a coumarin derivative in diabetic rats

Claudio Bucolo, Keith W. Ward, Emanuela Mazzon, Salvatore Cuzzocrea, Filippo Drago

Research output: Contribution to journalArticlepeer-review


Purpose. Retinal microvascular cells play a crucial role in the pathogenesis of diabetic retinopathy. The endothelial effects of cloricromene, a novel coumarin derivative, on diabetic retinop-athy induced by streptozotocin (STZ) in the rat were investigated. Methods. Cloricromene (10 mg/kg intraperitoneally) was administered daily in diabetic rats, and 60 days later eyes were enucleated for localization of nitrotyrosine, ICAM-1, VEGF, ZO-1, occludin, claudin-5, and VE-cadherin by immunohisto-chemical analysis. The effect of treatment was also evaluated by TNFa, ICAM-1, VEGF, and eNOS protein levels measurement in the retina with the respective ELISA kits. Blood-retinal barrier (BRB) integrity was also evaluated by Evans blue. Results. Increased amounts of cytokines, adhesion molecule, and nitric oxide synthase were observed in retina. Cloricromene treatment significantly lowered retinal TNFα, ICAM-1, VEGF, and eNOS. Furthermore, immunohistochemical analysis for VEGF, ICAM-1, nitrotyrosine (a marker of peroxynitrite), and tight junctions revealed positive staining in the retina from STZ-treated rats. The degree of staining for VEGF, ICAM-1, nitrotyrosine, and tight junctions was markedly reduced in tissue sections obtained from diabetic rats treated with clori-cromene. Treatment with cloricromene suppressed diabetes-related BRB breakdown by 45%. Conclusions. This study provides the first evidence that the new coumarin derivative cloricromene attenuates the degree of inflammation preserving the BRB in diabetic rats.

Original languageEnglish
Pages (from-to)3846-3852
Number of pages7
JournalInvestigative Ophthalmology and Visual Science
Issue number8
Publication statusPublished - 2009

ASJC Scopus subject areas

  • Ophthalmology
  • Sensory Systems
  • Cellular and Molecular Neuroscience
  • Medicine(all)


Dive into the research topics of 'Protective effects of a coumarin derivative in diabetic rats'. Together they form a unique fingerprint.

Cite this