Impact of alpha-tocopherol and vitamin C on endothelial markers in rats with streptozotocin-induced diabetes.
BACKGROUND
Overloads of reactive oxygen species in diabetes are associated with a number of pathological conditions, such as endothelial damage, which plays an important role in the initial stage of atherosclerosis. Plasma soluble thrombomodulin (sTM) and von Willebrand factor (vWF) have been found to be important markers of endothelial dysfunction.


METHODS
33 male Wistar rats were used for this experiment. All rats received standard rat chow and water. 25 rats were made diabetic by intra peritoneal injection of streptozotocin (STZ) (65 mg/kg) and divided into three groups. Group I was allowed free access to food and water, Group II received 30 mg vitamin C daily, and Group III received a-tocopherol in a dose of 600 mg/kg body weight.


RESULTS
At the end of the experimental period, there was significant elevation of sTM, vWF, fibrinogen, systolic blood pressure, and mean arterial blood pressure (MAP); however, there was a significant decrease in serum HDL cholesterol in the diabetic group in comparison to controls. Administration of antioxidants (vitamin C and a-tocopherol) caused attenuation of the endothelial damage, as vitamin C administration caused a significant decrease in sTM, vWF, fibrinogen and increased HDL-cholesterol, while a-tocopherol caused a significant decrease in vWF and sTM. Both vitamin C and a-tocopherol caused a significant decrease in systolic blood pressure and mean arterial pressure.


CONCLUSIONS
Our results suggest that administration of antioxidants may ameliorate the risk of thrombo-embolism in diabetes associated with hypertension.
Haidara
Mohamed A
MA
Department of Physiology, Kasr Al Aini Faculty of Medicine, Cairo University, Cairo, Egypt. haidaram@hotmail.com
Khloussy
Hemat
H
Ammar
Hania
H
Aal Kassem
Lobna Abdel
LA
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001158:Arteries / Q000187:drug effects / Q000502:physiology; D001205:Ascorbic Acid / Q000494:pharmacology*; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001835:Body Weight; D008076:Cholesterol, HDL / Q000097:blood; D003921:Diabetes Mellitus, Experimental / Q000097:blood* / Q000188:drug therapy / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D005340:Fibrinogen / Q000032:analysis; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D018180:Thrombomodulin / Q000097:blood; D024502:alpha-Tocopherol / Q000494:pharmacology*; D014841:von Willebrand Factor / Q000032:analysis
D000975:Antioxidants; D015415:Biomarkers; D008076:Cholesterol, HDL; D018180:Thrombomodulin; D014841:von Willebrand Factor; D005340:Fibrinogen; D024502:alpha-Tocopherol; D001205:Ascorbic Acid