Fig. 5.
Qu degradation increases caspase-3 and PARP cleavage. HaCaT cells were treated with 50 μmol/L Qu in the presence and absence of 1 mmol/L AA for 1 h before UVB irradiation and for 16 h after 250 J/m2 UVB. Cleavage of caspase-3 (A) and PARP (B) were induced by both UVB irradiation and Qu treatment alone. UVB irradiation followed by Qu treatment resulted in an increase in caspase-3 cleavage compared with either UVB or Qu alone. AA had no effect alone on caspase-3 or PARP cleavage; however, stabilization of Qu with AA resulted in a significant reduction in the cleavage of both proteins compared with Qu alone. Representative of three independent experiments.