title: Reduction of diabetes-induced oxidative stress by phosphodiesterase inhibitors in rats.
abstract: Increased oxidative stress has been suggested to be involved in the pathogenesis and progression of diabetic tissue damage. The aim of this study was to investigate the effect of different phosphodiesterase inhibitors on lipid peroxidation and total antioxidant capacity (TAC) of plasma in streptozotocin-induced diabetic rats (Rattus norvegicus). Rats became diabetic by a single administration of streptozotocin (STZ, 45 mg/kg). The effects of 15-days treatment by milrinone, sildenafil, and theophylline as cyclic-AMP and -GMP phosphodiesterase inhibitors (PDEIs) on diabetes-induced oxidative stress were studied. The levels of glucose, malonedialdehyde (MDA) the by product of lipid peroxides, and TAC (FRAP test) were estimated in plasma of control and experimental groups of rats. A significant increase in the levels of plasma glucose, and MDA and a concomitant decrease in the levels of TAC were observed in diabetic rats. These alterations were reverted back to near normal level after the treatment with PDEIs. Treatment of diabetic rats by PDEIs reduced MDA levels and increased TAC in the order of milrinone>sildenafil>theophylline. In conclusion, the present investigation show that PDIS possesses antioxidant activities, which may be attributed to their enhancing effect on cellular cyclic nucleotides contributing to the protection against oxidative stress in streptozotocin-induced diabetes. Exact mechanism of protective actions of cAMP- and cGMP-phosphodiesterase remains to be elucidated by further studies. This finding may suggest a place for PDEIs in maintaining health in diabetes.
authors.affiliation: Laboratory of Toxicology, Department of Pharmacology and Toxicology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Elham
authors.initials: E
authors.lastname: Milani
authors.forename: Shekoufeh
authors.initials: S
authors.lastname: Nikfar
authors.forename: Reza
authors.initials: R
authors.lastname: Khorasani
authors.forename: Mohammad Jafar
authors.initials: MJ
authors.lastname: Zamani
authors.forename: Mohammad
authors.initials: M
authors.lastname: Abdollahi
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000503:physiopathology*; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D020105:Milrinone / Q000627:therapeutic use; D018384:Oxidative Stress / Q000187:drug effects*; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D010879:Piperazines / Q000627:therapeutic use; D011687:Purines; D051381:Rats; D017208:Rats, Wistar; D000068677:Sildenafil Citrate; D013450:Sulfones; D013806:Theophylline / Q000627:therapeutic use; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D001786:Blood Glucose; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D017392:Thiobarbituric Acid Reactive Substances; D000068677:Sildenafil Citrate; D013806:Theophylline; D020105:Milrinone