Clinical Question:
Does antioxidants supplementation enhances antioxidant capacity, mitigates
oxidative damage, and may have an anti-inflammatory effect after acute
ischemic stroke?
Bottom Line:
Antioxidants supplementation with or without B-group vitamins enhances
antioxidant capacity, mitigates oxidative damage, and may have an
anti-inflammatory effect immediately postinfarct in stroke disease.
Reference:
Antioxidant supplementation with or without B-group vitamins after acute
ischemic stroke: a randomized controlled trial.Ullegaddi R, Powers HJ,
Gariballa SE. JPEN J Parenter Enteral Nutr. 2006 Mar-Apr;30(2):108-14.
Study Design:
Randomized Controlled Trial
Synopsis:
Evidence shows that there is a rapid increase in the production of markers
of oxidative damage immediately after acute ischemic stroke and that
endogenous antioxidant defenses are rapidly depleted, thus permitting
further tissue damage. Several studies point to an antioxidant effect of
B-group vitamins and a pro-oxidant effect of elevated total plasma
homocysteine (tHcy). To test whether supplementary antioxidants with or
without B-group vitamins during this critical period enhance antioxidant
capacity or mitigate oxidative damage, ninety-six acute ischemic stroke
patients within 12 hours of symptom onset were randomly assigned to receive
either daily oral 800 IU (727 mg) vitamin E and 500 mg vitamin C (n = 24),
or B-group vitamins (5 mg folic acid, 5 mg vitamin B(2), 50 mg vitamin B(6),
and 0.4 mg of vitamin B(12); n = 24), both vitamins together (n = 24), or no
supplementation (n = 24) for 14 days. Treatment groups and controls were
matched for stroke subtype and age. Blood was obtained before treatment, at
day 7, and day 14 for measurements of plasma or blood vitamin status, plasma
total antioxidant capacity (TAOC), malondialdehyde (MDA), tHcy and
C-reactive protein (CRP). Supplementation with antioxidant vitamins and
B-group vitamins separately or together significantly increased the plasma
concentration of vitamin C, E, pyridoxal phosphate (B(6) status), red blood
cell folate, and improved a measure of B(2) status (red cell glutathione
reductase activation coefficient [EGRAC]), compared with the control group.
Plasma TAOC increased significantly in the antioxidant treatment groups
compared with the nonsignificant decline seen in the control group. tHcy
concentrations decreased in subjects who received B-group vitamins and the
control group compared with the rise seen in those who received antioxidants
alone. There was a significant reduction in plasma MDA concentration in the
3 treatment groups, in contrast to the increase seen in the control group;
however, the changes were most evident in antioxidant groups. CRP
concentrations (a marker of tissue inflammation) were significantly lower in
the 3 treatment groups compared with the control group. There were no
additive or synergistic effects of antioxidants and B-group vitamins
together on any outcome measure. |