The role of mitochondrial quality surveillance in skin aging: Focus on mitochondrial dynamics, biogenesis and mitophagy.

The skin is the largest organ of the human body and the first line of defense against environmental hazards. Many factors, including internal factors such as natural aging and external factors such as ultraviolet radiation and air pollution, can lead to skin aging. Mitochondria provide sufficient energy to maintain the high-speed turnover capacity of the skin, so the quality control of mitochondria plays an indispensable role in this process. Mitochondrial dynamics, mitochondrial biogenesis and mitophagy are the key steps in mitochondrial quality surveillance. They are coordinated to maintain mitochondrial homeostasis and restore damaged mitochondrial function. All of the mitochondrial quality control processes are related to skin aging caused by various factors. Therefore, fine-tuning regulation of the above process is of great significance to the skin aging problem that needs to be solved urgently. This article mainly reviews the physiological and environmental factors causing skin aging, the effects of mitochondrial dynamics, mitochondrial biogenesis and mitophagy on skin aging, as well as their specific regulatory mechanisms. Finally, mitochondrial biomarkers for diagnosis of skin aging, and therapeutic approaches of skin aging via mitochondrial quality control were illustrated. The homeostasis of mitochondrial quality helps to ameliorate skin aging caused by internal and external factors. Both external factors such as ultraviolet (UV) radiation and pollution and internal factors such as natural aging and genetic inheritance can induce skin aging. These factors enhance the production of reactive oxygen species (ROS), promote inflammatory reaction, destroy DNA synthesis, increase matrix metalloproteinases (MMPs) in the skin, and thus accelerate skin aging. Mitochondrial dynamics, mitochondrial biogenesis and mitophagy are collectively involved in the regulation of skin aging. The balance between mitochondrial fission and fusion sustains the stability of mitochondria and attenuates skin aging. Mitochondrial biogenesis improves mitochondrial function and retards skin aging via generating new and healthy mitochondria. Mitophagy engulfs and degrades the damaged proteins and mitochondria, thus ensuring the mitochondrial quality and rescue skin aging (Created with Biorender.com). [Display omitted] • Internal and external factors accelerate the aging process of skin. • The homeostasis of mitochondrial quality affects skin aging. • Mitochondrial dynamics, mitochondrial biogenesis and mitophagy are mutually regulated. • Treatment via targeting mitochondrial quality control contributes to tackling skin aging. [ABSTRACT FROM AUTHOR]