title: Adenosine triphosphatase activity of streptozotocin-induced diabetic rat brain microsomes. Effect of vitamin E.
abstract: Hyperglycemia causes protein glycosylation, oxidation and alterations in enzyme activities, which are the underlying causes of diabetic complications. This study was undertaken to test the role of vitamin E treatment on Ca2+-ATPase activity, protein glycosylation and lipid peroxidation in the brain of streptozotocin (STZ)-induced diabetic rats. Male rats weighing about 250-300 g were rendered diabetic by a single STZ injection of 50 mg/kg via the tail vein. Both the diabetic and non-diabetic rats were fed a vitamin E supplemented diet (500 IU/kg/day). Ca2+-ATPase activity was significantly reduced at week 10 of diabetes compared to the control group (p < 0.05), with 0.225+/-0.021 U/I (mean +/- S.E.M.) in the control group and 0.072 +/- 0.008 U/l (mean +/- S.E.M.) in the diabetic group. Vitamin E treatment prevented the enzyme activity from decreasing. The activities observed were 0.226 +/- 0.020 U/l and 0.172 +/- 0.011 U/I (mean +/- S.E.M.) in the vitamin E-treated control and diabetic group, respectively. STZ-induced diabetes resulted in an increased protein glycosylation and lipid peroxidation. Vitamin E treatment led to a significant inhibition in blood glucose, protein glycosylation and lipid peroxidation, which in turn prevented abnormal activity of the enzyme in the brain. This study indicates that vitamin E supplementation may reduce complications of diabetes in the brain.
authors.affiliation: Ankara University, Faculty of Pharmacy, Department of Biochemistry, Ankara, Turkey. evcimen@pharmacy.ankara.edu.tr
authors.forename: N
authors.initials: N
authors.lastname: Das Evcimen
authors.forename: N N
authors.initials: NN
authors.lastname: Ulusu
authors.forename: C
authors.initials: C
authors.lastname: Karasu
authors.forename: B
authors.initials: B
authors.lastname: Doğru
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000201:enzymology*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000175:diagnosis / Q000178:diet therapy* / Q000201:enzymology*; D019587:Dietary Supplements; D004789:Enzyme Activation; D008297:Male; D008861:Microsomes / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin; D016896:Treatment Outcome; D014810:Vitamin E / Q000008:administration & dosage*
chemical_list: D001786:Blood Glucose; D014810:Vitamin E; D013311:Streptozocin; D000252:Calcium-Transporting ATPases