Table 2.

Effect of voluntary running wheel exercise for 2 weeks on UVB-induced apoptotic sunburn cells, caspase 3 (active form)-positive cells, and phospho-p53 (Ser-15)-positive cells in the epidermis of SKH-1 mice

Group	% Apoptotic sunburn cells		% Caspase 3-positive cells		% Phospho-p53 (Ser-15)-positive cells
	Exp. 1	Exp. 2	Exp. 1	Exp. 2	Exp. 1	Exp. 2
No running wheel	0.24 ± 0.04	0.22 ± 0.04	0.26 ± 0.06	0.22 ± 0.04	3.00 ± 0.14	3.53 ± 0.46
Running wheel	0.51 ± 0.09*	0.50 ± 0.10*	0.55 ± 0.10*	0.50 ± 0.10*	3.44 ± 0.33	4.02 ± 0.68
% increase	113	127	112	127	15	14

Female SKH-1 mice (7–8 weeks old, 10 mice per group) were in cages with a running wheel, and other mice (10 per group) were in cages without a running wheel for 2 weeks. The mice were irradiated once with UVB (30 mJ/cm²) and killed 6 h later. Additional sedentary and exercising mice (10 per group) were not irradiated with UVB. In the absence of UVB irradiation, the number of apoptotic sunburn cells or phospho-p53 (Ser-15)-positive cells in mice with or without a running wheel was ≤0.02%. Apoptotic sunburn cells were measured morphologically, and caspase 3-positive cells and phospho-p53 (Ser-15)-positive cells were measured immunohistochemically. Each value represents the mean ± SE. ∗, P < 0.01.