Research Paper Volume 9, Issue 12 pp 2647—2665

Clock mediates liver senescence by controlling ER stress

Figure 2. ClockΔ19 mice exhibit oxidative damage and DNA damage. (A) ROS activities were detected in the primary hepatocytes of WT and Clock∆19 mice (n=4 for all groups). (B) Relative expression of oxidation-related genes in WT and ClockΔ19 mice. Data were analyzed by Student’s t-test and displayed as the mean ± S.E.M. (n=4). **, P<0.01; *, P<0.05. (C) SOD, MDA, GSH and CAT activities were analyzed in liver tissue homogenate from WT and Clock∆19 mice (n=4). **, P<0.01; *, P<0.05. (D) Immunoblots of γ-H2AX and PARP in mouse liver tissues at ZT0 and ZT12. The spliced form of PARP (C-PARP) indicates DNA damage. Note that γ-H2AX was activated in Clock∆19 mice (n=4). **, P < 0.01 and *, P < 0.05 versus control. n=4 mice per group. (E) Immunoprecipitation of activated Caspase 3 (Cleaved-Caspase 3), which is activated in response to liver cell apoptosis activity. Mice had the same treatment as in (D). (n=4). **, P < 0.01; *, P < 0.05.