FIG. 1.

Effect of UVB irradiation on the proliferation and survival of ASCs. (A) Proliferation was measured 72 h after UVB irradiation using MTT assay. A low-dose UVB exposure did not affect, while a high dose reduced the ASC proliferation. (B) H₂O₂ treatment (0.5 mM for 24 h) induced the cell death, but low-dose UVB preconditioning increased ASC survival. (C) H₂O₂ treatment enhanced the PI staining of ASC nuclei, which was attenuated by UVB irradiation. (D) Western blot analysis showed that the phosphorylation of survival-related signaling molecules was significantly increased by UVB treatment. **P<0.01. UVB, ultraviolet B; ASCs, adipose-derived stem cells; H₂O₂, hydrogen peroxide; PI, propidium iodide. Color images available online at www.liebertpub.com/scd