Antioxidant status and α1-antiproteinase activity in subarachnoid hemorrhage patients

Abstract

The antiproteasic activity of alpha1-antitrypsin (α1-AT) is reduced in cases of subarachnoid hemorrhage from ruptured intracranial aneurysm and particularly in patients currently smoking; α1-AT is very sensitive to oxidant agents. About 50% of physiological anti-oxidant systemic capacity is represented by Vitamin A, E and C. Plasmatic amounts of α1-AT, α1-AT Collagenase Inhibitory Capacity (CIC) and levels of vitamin A, vitamin E and vitamin C were analyzed in 39 patients, 26 women and 13 men, operated for intracranial aneurysm; 11 patients with unruptured intracranial aneurysm were considered as controls while 28 patients were included within 12 hours from subarachnoid hemorrhage (SAH). Plasmatic levels of vitamin A and vitamin E were significantly lower (p = 0.038 and p=0.0158) in patients suffering SAH than in controls, while no statistically significant differences were found in mean plasmatic vitamin C levels. Level of α1-AT was not statistically different in controls and in patients with SAH; however, the activity of α1-AT, evaluated as CIC, is significantly reduced in patients with SAH (p = 0.019). We have observed that systemic plasmatic levels of vitamins did not significantly differ in relation to smoking habit. Vitamin A and E represent an important defensive system against free radicals reactions. Particularly, vitamin E acts as an antioxidant by scavenging free-radicals. A reduced anti-oxidant status might be related to the higher sensibility of α1-AT to oxidative reactions and the activity of α1-AT is dependent on the antioxidant capacity of liposoluble vitamins. We can speculate that an acute systemic oxidative stress condition might influence the rupture of intracranial aneurysms.