Evaluation of Serum Superoxide Dismutase Activity, Malondialdehyde, and Zinc and Copper Levels in Patients With Keratoconus.
OBJECTIVE
The aim of this study was to evaluate the relationship between antioxidant superoxide dismutase (SOD) enzyme activity, malondialdehyde (MDA) as a lipid peroxidation marker, and some trace elements such as zinc (Zn) and copper (Cu) levels in patients with keratoconus.


METHODS
A total of 58 patients with keratoconus and 53 control subjects with similar age and sex were evaluated in this study. The modified Krumeich keratoconus classification was used to divide the patients into 4 stages. Serum SOD activity, MDA, and zinc and copper levels were compared between the patient and control groups.


RESULTS
The median serum SOD activity, MDA, and Zn and Cu levels were 27.2 (42.4-13.7) U/mL, 10.2 (11.9-8.5) nmol/mL, 87.9 (104.6-76.5) μmol/L, and 103.2 (117.9-90.3) μmol/L in the keratoconus group and 26.2 (32.5-14.4) U/mL, 8.8 (11.4-7.1) nmol/mL, 100.5 (121.1-81.8) μmol/L, and 98.4 (120.3-83.4) μmol/L in the control group, respectively. There was a statistically significant difference between the MDA and Zn levels of the keratoconus group and control subjects but not between the respective SOD activities or Cu levels (P = 0.016, P = 0.031, P = 0.440, and P = 0.376, respectively). We found no significant difference between the keratoconus group stages for serum SOD activity, serum MDA, and Zn and Cu levels (P > 0.05), and there was also no significant correlation between the keratoconus group stages and serum SOD activity, serum MDA, and Zn and Cu levels (P > 0.05).


CONCLUSIONS
There is imbalance in the systemic oxidant/antioxidant status where Zn deficiency also plays a role in patients with keratoconus.
*Department of Ophthalmology, Faculty of Medicine, Ahi Evran University, Kırşehir, Turkey;†Department of Biochemistry, Faculty of Medicine, Gazi University, Ankara, Turkey; and‡Ulucanlar Eye Training and Research Hospital, Ankara, Turkey.
Raşit
R
Kılıç
Aslhan Cavunt
AC
Bayraktar
Serdar
S
Bayraktar
Ali
A
Kurt
Mustafa
M
Kavutçu
D000328:Adult; D003300:Copper / Q000097:blood*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000097:blood*; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood*; D013054:Spectrophotometry, Atomic; D013482:Superoxide Dismutase / Q000097:blood*; D017392:Thiobarbituric Acid Reactive Substances; D015032:Zinc / Q000097:blood*
D017392:Thiobarbituric Acid Reactive Substances; D008315:Malondialdehyde; D003300:Copper; D013482:Superoxide Dismutase; D015032:Zinc