Table 1.
Effect of various challenges plus 6 h of normal culture on the activities of three antioxidant enzymes in human lens epithelial cells.
| Percent decrease in activity compared to control |
||||||
|---|---|---|---|---|---|---|
| Enzyme | CDNB ALONE | BSO ALONE | CDNB + UVA, 3% O2 |
CDNB + UVA, 20% O2 |
BSO + UVA, 3% O2 |
BSO + UVA, 20% O2 |
| GSHPx | 24 ± 13a
(16) |
9 ± 10 (11) |
44 ± 13b,d
(8) |
58 ± 10c,f,g
(8) |
19 ± 26 (9) |
12 ± 14 (4) |
| TrxR | 25 ± 13 (15) |
9 ± 14 (7) |
63 ± 7c,e
(7) |
69 ± 3c,f,g
(8) |
14 ± 20 (8) |
18 ± 16 (3) |
| GR | 13 ± 12a
(8) |
6 ± 15 (7) |
20 ± 5 (4) |
23 ± 7 (4) |
10 ± 10 (7) |
not determined |
The cells were pretreated with BSO (overnight) or CDNB (10 min), exposed to UVA light for 1h at either 3% or 20% O2 and cultured normally for 6h. Each result is expressed as the mean ± S.D. The number of experiments is in parentheses. Control activities; GSHPx: 0.011±0.004 units/mg protein (20); TrxR: 5.1 ± 2.9 ΔO.D. at 412nm/mg protein (14); GR: 0.058±0.006 units/mg protein (12).
a
p<0.05 to control;
b
p<0.01 to CDNB alone;
c
p<0.001 to CDNB alone;
d
p<0.05 to BSO + UVA (3% O2);
e
p<0.001 to BSO + UVA (3% O2);
f
p<0.001 to BSO + UVA (20% O2),
g
p<0.05 to CDNB + UVA (3% O2).