Mice were divided into 4 groups (n=8 each): 1) sham exposure for 24 hours (sham), ultraviolet radiation for 1 hour (UV), exposure to the magnetic field for 24 hours (MF), 2) exposure to the magnetic field for 24 hours, ultraviolet radiation for 1 hour, exposure to the magnetic field for 24 hours, 3) sham exposure for 24 hours, ultraviolet radiation for 1 hour, sham exposure for 24 hours, 4) non-exposed control group.
The delivered UV radiation dose during 1 hour was 400 J/m2.
In the test on p53 protein expression, a known p53-positive skin tumor sample was used as a positive control. A sample processed without the primary antibody was used as a negative control.
Exposure duration: continuous for 24 h (group 1) or 2 times for 24 h (group 2)
|Exposure duration||continuous for 24 h (group 1) or 2 times for 24 h (group 2)|
|magnetic flux density||100 µT||-||-||-||-|
Apoptosis was increased in all exposure groups (groups 1-3) compared to the control group, with the highest value in in group 3 (sham + UV + sham). Group 1 (sham + UV + MF) showed significantly less apoptosis compared to group 3. Group 2 (MF + UV + MF) also showed a decrease in apoptosis in comparison to group 3 but it was just not significant.
A protein expression of p53 was not detected in any group.
No significant differences in the ornithine decarboxylase enzyme activity were found between the exposure groups.
In the polyamine levels, spermidine and spermine showed a significant decrease in group 2 (MF + UV + MF) compared to group 3 (sham + UV + sham).
The authors conclude that exposure of mice to ultraviolet radiation might induce p53-independent apoptosis in the skin and that exposure to a magnetic field could attenuate this effect.