Molecular mechanisms of skin aging

At the cellular and molecular levels, the limited ability of aged fibroblasts and keratinocytes to respond to changes in their environments fits nicely the concept of aging as inability of the organism to respond adaptively to environmental changes. Whether these molecular changes represent cumulative random genetic damage or programmed aging process cannot be determined. Nevertheless, the data correlate with the well-known differences in biologic responsiveness between newborn, young adult, and old adult cells. Thus, our findings represent a beginning from which more comprehensive understanding of molecular changes involved in cutaneous aging will evolve.