Transcript Supplementary Figure 2 - PowerPoint (100 KB )

Figure S2
Young
Heterochronic
Isochronic
Heterochronic
Laminin/BrdU
Isochronic
Aged
Figure S2 Heterochronic parabiosis restores fiber regeneration in old mice.
As in Figure 1, five days after injury, muscles from isochronic and heterochronic parabionts
were analyzed for indices of regeneration. BrdU was injected intraperitoneally 2 days after
the injury to label proliferating cells. Shown are muscle sections immunostained for laminin
(red) and BrdU (green). BrdU+ nuclei were present in regenerating fibers of muscle from
young mice. In isochronically paired aged mice, most BrdU+ nuclei were located in the
interstitial spaces. However, in aged mice in heterochronic pairings with young mice, the
enhanced regeneration (see Fig. 1) was accompanied by an increase in the incorporation of
BrdU+ nuclei into regenerating fibers.