الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
The present study was conducted to investigate the effect of resveratrol (RSV) in preventing cardiovascular complications of diabetes. In addition, the study attempted to evaluate the role of heme oxygenase-1 (HO-1) in mediating the effects of RSV in this setting.
In this study, induction of diabetes was achieved via injection of a single dose of streptozotocin (50 mg/kg). After 7 days of STZ injection, 48 male Wistar rats were randomized into two groups; Control rats and diabetic rats. Control rats were subdivided into vehicle-treated group and RSV-treated group. While, the diabetic rats were randomized into four groups; diabetic rats treated with vehicle, diabetic rats treated with RSV, diabetic rats treated with combination of RSV and Zinc protoporphyrin and diabetic rats treated with zinc protoporphyrin alone. After 4 weeks, rats were sacrificed and blood and tissue samples were collected.
Various tests have been done using heart and aorta as well as serum. These analyses include:
Biochemical analyses involving measurement of blood glucose levels, superoxide dismutase activity in aortic tissues, malondialdehyde concentration in the heart and serum, nitrite concentration in aortic tissues, HO-1 protein expression and activity as well as TGF-and eNOS expressions in heart and aorta.
Histopathological examination of heart and aortic tissues from each group.
Measurement of vascular function through assessment of vascular reactivity to determine the endothelial dependent and endothelial-independent relaxation as well as contractile function of aortic rings and its response to L-arginine.
Results showed that induction of diabetes via injection of STZ (50 mg/kg, I.P) produced detrimental effects on cardiovascular function. Diabetic rats
Summary and conclusion
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demonstrated histopathological changes compared to normal rats. These changes were associated with increased oxidative stress as shown by increased levels of MDA. Moreover, the expression of TGF was increased and eNOS expression was reduced. These results were associated with a reduction in HO-1expression. These pathological changes were observed in both heart and aortic tissues. In addition, STZ- induced diabetes was associated with vascular dysfunction as shown by decreased endothelium dependent relaxation of aortic rings.
Chronic treatment with RSV (10 mg/kg) attenuated the biochemical changes in diabetic heart and restored the vascular function. RSV treated rats showed increased expression of HO-1, eNOS and reduced expression of TGF- in both heart and aortic tissues in addition to prevention of diabetes induced-elevation in cellular oxidative stress which was demonstrated as decrease in TBARS and rise in activity of SOD. The histopathological features were also improved compared to diabetic control rats.
However, RSV-induced protective effects on heart were abolished when combined with ZnPP while, its effects on endothelial function were partially attenuated. Thus, these results clarify the role of HO-1 induction in protective effects of RSV in diabetic settings. Meanwhile, HO-1 induction in normal conditions had no significant beneficial effects on cardiovascular functions as demonstrated by results of biochemical, histopathological and functional analysis of tissues obtained from normal rats chronically treated with RSV.
In conclusion, diabetes induces detrimental effects on cardiovascular function that can be attenuated by chronic treatment with RSV. Additionally.