Vitamin C affects thrombosis/ fibrinolysis system and reactive hyperemia in patients with type 2 diabetes and coronary artery disease.

Journal article

OBJECTIVE: To examine the effect of vitamin C on forearm vasodilatory response to reactive hyperemia and on plasma level of plasminogen activator inhibitor 1 (PAI-1), von Willebrand factor (vWF), tissue plasminogen activator (tPA), antithrombin III (ATIII), proteins C and S, and factors V (fV) and VII (fVII) in patients with both type 2 diabetes and CAD. RESEARCH DESIGN AND METHODS: A total of 39 patients with type 2 diabetes and CAD were divided into two groups and received vitamin C (2 g/day) or no antioxidant for 4 weeks. Forearm blood flow was determined using venous occlusion gauge-strain plethysmography at baseline and after treatment. Forearm vasodilatory response to reactive hyperemia (RH%) or nitrate (NTG%) was defined as the percent change of flow from baseline to the maximum flow during reactive hyperemia or after administration of nitrate, respectively. Biochemical markers were determined by enzyme-linked immunosorbent assay (ELISA) or other standard methods. RESULTS: RH% was significantly increased after treatment with vitamin C (from 62.4 +/- 7.2 to 83.1 +/- 9.3%, P = 0.024) but remained unaffected in the control group. Vitamin C decreased plasma levels of fV (from 143 +/- 5.4 to 123 +/- 6.03%, P = 0.038), vWF (from 133.5 +/- 14.5 to 109.5 +/- 11.4%, P = 0.016), and tPA (from 12.3 +/- 0.99 to 8.40 +/- 0.60 ng/ml, P = 0.001), whereas these levels remained unaffected in the control group. The changes in RH%, vWF, and tPA were significantly greater (P = 0.028, 0.036, and 0.007, respectively) in the vitamin C-treated group than in the control group. Levels of ATIII, proteins S and C, fVII, and PAI-1 remained unchanged in all groups. CONCLUSIONS: Short-term treatment with high doses of vitamin C improved RH% and decreased plasma levels of tPA and vWF in patients with type 2 diabetes and CAD.

Authors: Tousoulis, D; Antoniades, C; Tountas, C; Bosinakou, E; Kotsopoulou, M

• Journal: Diabetes care
• Volume: 26
• Issue: 10
• Pages: 2749-2753
• Publication date: 2003-10-01
• DOI: 10.2337/diacare.26.10.2749
• EISSN: 1935-5548
• ISSN: 0149-5992
• Language: English
• Keywords: Hyperemia; Female; Factor VII; Diabetes Mellitus, Type 2; Forearm; Coronary Artery Disease; Thrombosis; Ascorbic Acid; Protein S; Vasodilation; Tissue Plasminogen Activator; Fibrinolysis; Factor V; Middle Aged; Male; Aged; Administration, Oral; Antioxidants; Humans; Protein C; Regional Blood Flow; von Willebrand Factor; Antithrombin III; Plasminogen Activator Inhibitor 1