November 2022 — Vol 142 No 11

Images of the skin in animals aged 3 and 23 years. Note the more translucent and less pigmented dorsal skin in aged NMR.

Like in human skin, aging in naked mole rats corresponds with a decrease in epidermal thickness, keratinocyte proliferation, and a reduction of melanocyte numbers. The figure shows the difference in skin pigmentation of young and old naked mole rats. Further similarities to aged human skin include a decrease of dermal collagens and increased levels of MMP9 and 11. However, by contrast to human skin, expression of transcripts of several longevity-associated genes and tumor suppressor genes is increased in skin of aged naked mole rats. Fatima et al. suggest that specific features in the naked mole rat skin aging transcriptome might play a role in the resistance of these animals against spontaneous skin carcinogenesis. The authors propose naked mole rats as a model organism for studying the biology, disease resistance, and susceptibility of aging human skin.