Plasma longitudinal changes of carotenoids and malondialdehyde in stroke patients: relationship to outcome
Experimental research suggests the association between ischemic stroke and increased oxidative stress. Carotenoids are lipid-soluble molecules with antioxidant activity, but changes of their plasma concentrations during stroke have been never evaluated. Twenty-eight consecutive patients (19M, 9F, mean age 77 y) with acute ischemic stroke (onset < 24 hrs) were divided in subgroups according to the functional outcome at one week as assessed by Barthel Index: group 1 - pts who died or experienced functional decline; group 2 - pts who remained functionally stable. Plasma levels of carotenoids including lutein, zeaxanthin, b-cryptoxanthin, lycopene, α- and β-carotene, and of malondialdehyde (MDA), a marker of lipid peroxidation, were measured on admission, after 6 and 24 hrs, and then on days 3, 5 and 7, by HPLC. Levels on admission were compared to those of age- and sex-matched controls (ctrls). On admission, plasma carotenoid levels were significantly lower (lutein, p<.005; zeaxanthin, p<.05; lycopene, p<.001; α-carotene, p<.004; β-carotene, p<.001) and plasma MDA significantly higher (p<.001) in pts than in ctrls. Plasma carotenoids showed a trend towards a decrease during the first 24 hrs after admission, independently of dietary intake and cholesterol levels. The time-course changes of lutein, α-carotene and lycopene plasma levels up to one week showed higher concentrations in group 2 as compared to group 1 patients. Differences reached statistical significance for lutein (p<.01). Plasma MDA levels tended to decrease over time and were significantly lower in group 2 as compared to group 1 (p<.005). We conclude that carotenoids, which are lipophilic antioxidants, are significantly lower in plasma from stroke patients compared to controls, and are reduced immediately after stroke. Lutein, lycopene and α-carotene are particularly reduced in patients with the worst outcome at one week. MDA is significantly higher in stroke patients on admission compared to controls and is highest in patients who died or declined functionally. A specific carotenoid and lipid peroxidative pattern is associated with a poor early outcome in ischemic stroke.