Proteostasis and Skin Aging

Skin aging depends on both intrinsic and extrinsic factors, including exposure to UV light and pollution, while several hallmarks of aging such as loss of proteostasis and mitochondrial dysfunction have been reported to be important contributors to both chronological and photoaging. Indeed, aged skin is characterized by the occurrence of damaged mitochondria, mtDNA deletions, increased production of reactive oxygen species and the accumulation of oxidatively modified proteins which are accompanied by constant decline in mitochondrial function in both dermal and epidermal layers. Since protein degradation represents a key process for the maintenance of protein homeostasis at the intracellular and intra-mitochondrial levels, the role of mitochondrial proteases, autophagy and proteasome, their interconnections and their alterations upon skin aging are addressed in this chapter.