Prolonged antioxidant vitamin E and /or C supplementation could be effective to improve endothelial function in non-obese T2DM subjects
Controversy exists among trials assessing whether prolonged antioxidant vitamin supplementation improves endothelial function in type 2 diabetes mellitus ( T2DM ) subjects .
The aim of this study was to systematic ally review and quantify the effect of antioxidant vitamin supplementation on endothelial function in T2DM subjects .
Effect of ascorbic acid on microcirculation in patients with Type II diabetes: a randomized placebo-controlled cross-over study.
Manifestations of vascular disease , including microvascular changes , constitute the major part of the morbidity and mortality in diabetic patients . Oxidative stress has been suggested to play an important role in the vascular dysfunction of diabetic patients . Furthermore , epidemiological observations indicate a beneficial effect of an increased dietary intake of antioxidants . The present study tested the hypothesis that the antioxidant ascorbic acid influences microcirculatory function in patients with Type II diabetes . Patients with Type II diabetes were treated with 1 g of ascorbic acid three times a day for 2 weeks in a r and omized placebo-controlled double-blind cross-over design . Microvascular reactivity was assessed by  vital capillaroscopy  and PRH ( post-occlusive reactive hyperaemia ) . hs-CRP ( high-sensitivity C-reactive protein ) , IL-6 ( interleukin-6 ) , IL-1ra ( interleukin-1 receptor antagonist ) and ox-LDL ( oxidized low-density lipoprotein ) were analysed . The results showed no significant change in microvascular reactivity assessed after 2 weeks of ascorbic acid treatment . TtP ( time to peak ) was 12.0+/-3.3 s before and 11.2+/-3.5 s after ascorbic acid ( n=17 ) . In comparison , TtP was 11.5+/-2.9 s before and 10.6+/-2.8 s after placebo ( not significant ) . IL-1ra , IL-6 , hs-CRP and ox-LDL did not change significantly after ascorbic acid , neither as absolute or relative values . In conclusion , in contrast with some studies reported previously , we could not demonstrate an effect of continuous oral treatment with ascorbic acid on microvascular reactivity assessed at the level of individual capillaries . Furthermore , we found no indication of an effect on inflammatory cytokines or ox-LDL
Prolonged antioxidant vitamin E and /or C supplementation could be effective to improve endothelial function in non-obese T2DM subjects
Controversy exists among trials assessing whether prolonged antioxidant vitamin supplementation improves endothelial function in type 2 diabetes mellitus ( T2DM ) subjects .
The aim of this study was to systematic ally review and quantify the effect of antioxidant vitamin supplementation on endothelial function in T2DM subjects .