ABSTRACT
Aim To investigate the possible effect of N-acetyl-leu-leu-norleucinal (ALLN),an inhibitor of Calpain,on H2O2-induced damage in 661W cells.Methods The cellular survival of 661W treated with different doses of H2O2 without or with ALLN for 24 h was measured by MTT assay.The protein level of Calpain 1 and Calpain 2 was assessed by Western blot.Results Upon the H2O2 treatment at the concentrations of 50,100,500,1 000 μmol · L-1,the survival rate of 661W significantly decreased in a dose-dependent manner compared to that of the control group.Furthermore,the protein level of Calpain 1 and Calpain 2 showed an obviously time-dependent increase in 661W cells treated with 100 μmol · L-1 H2O2 for 12,18,24 h.Finally,the survival rate of 661W treated with ALLN and H2O2 was higher than that treated only with H2O2,and there was no difference in survival rate between ALLN groups (at the concentrations of 25,50,100,200 μmol · L-1) and control group.Conclusions Calpain is involved in the damage induced by H2O2.ALLN,the inhibitor of Calpain,attenuates the oxidative damage,which plays a promising protective role in photo-receptor cells under oxidative stress.