Abstract
Purpose: :
Aldose reductase (AR) and inflammation have been implicated in the pathogenesis of diabetic retinopathy. The aim of this study was to investigate effects of aldose reductase deletion on diabetes-induced inflammatory changes in the retina, and on vascular pathology
Methods: :
Wild-type (C57BL/6J) and aldose reductase (AR) deficient mice were made diabetic with streptozotocin. Mice were sacrificed at 2 mos and 10 mos of study to evaluate retinal vascular histopathology (elastase digestion), as well as parameters of oxidative stress (retinal superoxide) and inflammation (expression of inflammatory proteins).
Results: :
Wild-type mice diabetic for 10 mos developed the expected degeneration of retinal capillaries, and diabetes of 2 mos duration increased both superoxide production and expression of iNOS and ICAM. Co-culture of endothelial cells with leukocytes from wildtype diabetics killed more endothelial cells than did leukocytes from nondiabetics. Deletion of AR resulted in total suppression of the diabetes-induced increase in expression of iNOS and generation of retinal superoxide, and partial inhibition of vascular histopathology. Neither leukocyte-mediated killing of endothelial cells or increased expression of ICAM, however, were corrected in AR-deficient diabetic mice.
Conclusions: :
AR regulates the diabetes-induced increase in superoxide generation by the retina, and regulate some, but not all, aspects of the diabetes-induced inflammation and capillary degeneration.
Keywords: diabetic retinopathy • pathology: experimental • inflammation