Figure 3. Macro-environment extra-follicular modulators, Bmp2, Dkk1 and Sfrp4, are up-regulated in old mice.
Whole mount in situ hybridization (WMISH) of dorsal skin stripes taken from 24 month old mice. Hair cycle stages are estimated based on propagating hair waves. a. Bmp2 and Wnt signaling pathway inhibitors, including Dkk1 and Sfrp4, should have been negative in the propagating anagen in the normal adult (e.g., 6 month old) mice. But they are expressed during this stage in the 24 month old mice. b. Quantitative RT-PCR from intra-dermal adipose tissues revealed of the skin from 24 months old mice show an overall up-regulation of inhibitors in all hair cycling phases, comparing to 6 month old young mice.