Prevention of pericyte loss by trolox in diabetic rat retina.
Prolonged hyperglycemia results in a number of diabetic complications, including retinopathy. Pericyte degeneration is one of the earliest histological changes observed in the development of diabetic retinopathy. Increased free radicals generated under hyperglycemia could damage the retina, which abounds in polyunsaturated fatty acids. In the current study, a severalfold increase in thiobarbituric acid-reactive substances was found in rat retina cultured in hyperglycemic medium, which decreased significantly when trolox, an amphipathic antioxidant, was included in the medium. To examine the contribution of oxidative stress in vivo, diabetic rats were fed trolox (0.4% in the diet) during the course of the experiments. After 5 mo of hyperglycemia, whole mounts of retinal vessels were prepared and endothelial cells (E) and pericytes (P) were counted. The ratio of E/P in the retinas obtained from normal rats, diabetic rats, and diabetic rats fed trolox were 1.74 +/- 0.186, 3.78 +/- 0.47, and 2.32 +/- 0.24, respectively. A significant restoration of pericytes by trolox suggests the involvement of oxidative injury during pericyte loss in diabetic retinopathy.
Ansari
N H
NH
Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77555-0647, USA. ansari@utmb.edu
Zhang
W
W
Fulep
E
E
Mansour
A
A
D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage*; D002196:Capillaries / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002452:Cell Count / Q000187:drug effects; D002839:Chromans / Q000008:administration & dosage*; D003921:Diabetes Mellitus, Experimental / Q000150:complications; D003930:Diabetic Retinopathy / Q000209:etiology / Q000517:prevention & control*; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D012171:Retinal Vessels / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D000975:Antioxidants; D002839:Chromans; D017392:Thiobarbituric Acid Reactive Substances; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid