Research Paper Volume 1, Issue 9 pp 784—802

Figure 6. Fibroblasts from young (4-6 mos) and old (21-24 mos) dwarf mice show resistance to rotenone-induced p38 MAPK activation. Induction of phosphorylation of the p38 MAPK catalytic site amino acid residues (P-Thr¹⁸⁰/P-Tyr¹⁸²) by ROT is significantly lower in fibroblasts derived from young and old dwarf mice. (A) The time course of activation of the p38 MAPK catalytic site by rotenone (5 μM and 20 μM) in fibroblasts from young (4-6 mos) wild-type and Ames dwarf mice shows the differences in levels of response to 5 μM and 20 μM ROT. (B) A time course of the activation of old (21-24 mos) wild-type and dwarf mouse fibroblasts in response to 5 μM and 20 μM ROT shows that the level of activation of p38 MAPK catalytic site in aged wild-type and dwarf fibroblasts increases with age. The Western blot time course analyses below each bar graph show that the phosphorylated levels of the p38 MAPK catalytic site are significantly lower in Ames dwarf fibroblasts than their sage matched wild-type controls. n = 4; * p<0.05 between wild-type and dwarf.