This chapter reviews the role of cellular senescence in skin aging, and potential impact of skin stem cells and their senescence on skin aging. Different cell types present in skin contribute to skin aging in various ways depending on the natural function of a particular cell type. Apart from cell type-specific functions, a common phenotype termed cellular senescence, which all these cell types undergo, contributes to a differential gene expression profile, which is detrimental to well being of skin such as physical appearance of the skin, and its ability to withstand natural wear and tear. Cellular senescence may also contribute to the depletion of skin stem cell pool, which could affect the regeneration of various skin cell types that differentiate to generate various skin layers. Recent work from various laboratories suggest that p16 inactivation and/or Bmi-1 overexpression can maintain stem cell characteristics in keratinocytes and other cell types. These studies offer intriguing possibilities of maintaining stem cell pools in skin and delaying senescence, and ultimately, skin aging by using reagents that either downregulate p16 expression or upregulate and maintain Bmi-1 expression. Recently, it has been suggested that expression of various defined transcription factors such as Oct3/4, Nanog, Sox2 and Tcf4 can maintain stem cell-like characteristics, and can even induce dedifferentiation of adult fibroblasts and keratinocytes. These studies provide new and exciting avenues of research in skin aging and offer possibilities of postponing aging and its unwanted effects on skin.
|Title of host publication||Skin Aging Handbook|
|Number of pages||20|
|Publication status||Published - 2009|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)