Research Paper Volume 4, Issue 1 pp 3—12

Figure 1. Cellular senescence and mitochondrial activity in skin of aging mice. (A) Representative photomicrographs of dorsal skin sections from C57BL/6J WT mice, aged 4 mos or 2 yrs, stained for SA-βgal activity (blue) and counterstained with nuclear fast red (red). Arrows indicate SA-βgal+ cells. (B) Percent of C57BL/6J WT mice, aged 4 mos, 8 mos or 2 yrs, with SA-βgal positive (+) or negative (−) activity. (C) Representative photomicrographs of dorsal skin sections from the same mice, aged 4 mos or 2 yrs, stained for succinate dehydrogenase (SDH) (blue) activity. Arrows indicate staining in epidermis. (D) Percent of the same mice, aged 4 mos, 8 mos or 2 yrs, with SDH positive (+) or negative (−) activity. A total of six 4-month old (3 males and 3 females), ten 8-month old (5 males and 5 females), and thirteen 24-month old (7 males and 6 females) mice were analyzed.