Purchase this article with an account.
E.C. Leal, C.A. Aveleira, A. Castilho, K.–I. Hosoya, A.F. Ambrosio, J.V. Forrester; High Glucose, Oxidative and Nitrosative Stress Increase Leukocyte Adhesion to Retinal Endothelial Cells in Culture . Invest. Ophthalmol. Vis. Sci. 2006;47(13):1706.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Leukocyte adhesion to retinal vessels is believed to play an important role in the pathogenesis of diabetic retinopathy (DR). Also, some evidences indicate that oxidative and nitrosative stress might be involved in the early events of DR, such as leukocyte adhesion and blood–retinal barrier breakdown. We investigated the mechanisms underlying leukocyte adhesion to retinal endothelial cells, which were exposed to high glucose or oxidative–nitrosative conditions, using an in vitro model.
Rat retinal endothelial cells (TR–iBRB2 cell line) were incubated with high glucose (30 mM; 4 days), NOC–18 (250 µM; 24h) or H2O2 (100 µM; 24h). The levels of intercellular adhesion molecule (ICAM–1) were quantified by flow cytometry and the in vitro adhesion of leukocytes was evaluated with a fluorescence assay.
High glucose, NOC–18 and H2O2 increased both ICAM–1 levels and leukocyte adhesion to endothelial cells. These effects were inhibited by the presence of an antibody against ICAM–1 or by LY379196, a PKC beta inhibitor. In addition, high glucose–induced leukocyte adhesion was prevented by L–NAME and aminoguanidine, which are nitric oxide synthase inhibitors.
These results show that oxidative and nitrosative stress, characteristic of hyperglycemic conditions, increase leukocyte adhesion to retinal endothelial cells due to an upregulation of ICAM–1, which is mediated by PKC beta. In addition, increased production of nitric oxide is also responsible for high glucose–induced increase in leukocyte adhesion.
This PDF is available to Subscribers Only