Serum uric acid levels correlate with plasma hydrogen peroxide and protein carbonyl levels in preeclampsia.
BACKGROUND
Increased serum uric acid has been postulated to directly promote oxidative stress. The aim of this study was to investigate whether serum uric acid level correlated with superoxide generation and oxidative stress in preeclampsia.


METHODS
We assessed serum uric acid levels, plasma hydrogen peroxide levels, and plasma protein carbonyl levels in normal pregnant (n = 14) and preeclamptic women (n = 17). Serum uric acid and plasma hydrogen peroxide levels were determined by the uricase-peroxidase method, a combined enzymatic-colorimetric method. Plasma carbonyl levels were measured by ELISA.


RESULTS
The mean serum uric acid values were significantly elevated in preeclampsia (6.6 +/- 1.5 mg/dl) compared with normal pregnancy (4.0 +/- 0.7 mg/dl) (P < 0.001). Plasma protein carbonyl levels were also significantly elevated in preeclampsia (7.72 +/- 4.10 nmol/mg) compared with normal pregnancy (2.85 +/- 3.06 nmol/mg) (P = 0.0011). In addition, the plasma hydrogen peroxide levels were significantly higher in preeclampsia (66.9 +/- 10.9 micromol/l) compared with normal pregnancy (50.1 +/- 5.6 micromol/l) (P < 0.001). Serum uric acid levels correlated significantly and positively with plasma hydrogen peroxide levels (r(2) = 0.2965, P = 0.0027) and plasma protein carbonyl levels (r(2) = 0.2011, P = 0.0129).


CONCLUSIONS
The increased serum uric acid levels correlated closely with plasma hydrogen peroxide levels and plasma protein carbonyl levels in preeclampsia. Therefore, the serum uric acid level serves as an indicator of the underlying oxidative stress in preeclampsia.
Tsukimori
Kiyomi
K
Department of Obstetrics and Gynecology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. tsuki@med.kyushu-u.ac.jp
Yoshitomi
Tomoyuki
T
Morokuma
Seiichi
S
Fukushima
Kotaro
K
Wake
Norio
N
D000328:Adult; D015415:Biomarkers / Q000097:blood; D003124:Colorimetry / Q000379:methods; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000097:blood*; D018384:Oxidative Stress; D011225:Pre-Eclampsia / Q000097:blood* / Q000175:diagnosis; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood* / Q000175:diagnosis; D011379:Prognosis; D050050:Protein Carbonylation; D012720:Severity of Illness Index; D013481:Superoxides / Q000378:metabolism*; D014527:Uric Acid / Q000097:blood*
D015415:Biomarkers; D013481:Superoxides; D014527:Uric Acid; D006861:Hydrogen Peroxide