Antioxidant defense capacity in scleroderma patients.
BACKGROUND
Oxidative stress is associated with scleroderma (systemic sclerosis) and is supposed to favor disease progression by complex effects on the vascular endothelium and on fibroblasts.


METHODS
Plasma oxidative process marker, thiobarbituric acid-reactive substances, and several markers of antioxidant defense capacity (plasma total antioxidant activity, serum albumin, uric acid and glutathione, superoxide dismutase and catalase) were evaluated by spectrophotometric methods using blood samples collected from 23 scleroderma patients and 21 healthy controls.


RESULTS
In scleroderma patients, thiobarbituric acid-reactive substances levels (mmol/L plasma) were significantly elevated (29.3+/-5.8) compared with healthy controls (16.6+/-3.1, p<0.001). Total antioxidant activity (mmol Trolox/L) was significantly lower in scleroderma patients than in controls (1.29+/-0.13 vs. 1.55+/-0.23, p<0.001), as well as the antioxidant gap (mmol Trolox/L) (0.57+/-0.18 vs. 0.92+/-0.22, p<0.001). Superoxide dismutase activity (IU/g hemoglobin) was markedly decreased in patients as compared with controls (395+/-184 vs. 659+/-211, p<0.001).


CONCLUSIONS
Lower plasma total antioxidant activity and plasma antioxidant gap in scleroderma patients show that plasma antioxidant defense is deficient in scleroderma patients. As previous studies on this issue are controversial, the decreased erythrocyte superoxide dismutase activity found in the patients in this study needs further investigation.
Sfrent-Cornateanu
Roxana
R
Department of Physiopathology and Immunology, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.
Mihai
Carina
C
Stoian
Irina
I
Lixandru
Daniela
D
Bara
Constantin
C
Moldoveanu
Elena
E
D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology; D012595:Scleroderma, Systemic / Q000097:blood*; D013482:Superoxide Dismutase / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism*
D000975:Antioxidants; D017392:Thiobarbituric Acid Reactive Substances; D013482:Superoxide Dismutase