Hair is a skin appendage that protects the skin from external factors such as physical stimuli, temperature changes, and ultraviolet light. Since hair also plays an important role aesthetically, many people are interested in hair growth and loss. Hair growth is a complex process, which is finely regulated by interactions between the various cells that make up the hair follicle. In particular, hair follicle stem cells are present in the bulge area of the hair follicle and since these cells can differentiate into various cells constituting the hair follicle, they play a pivotal role in maintaining the hair growth cycle. Hair follicle stem cells usually remain quiescent, but under certain circumstances, they become activated, start dividing, and migrate to the lower part of the bulge to form anagen hair follicle. Along with many genes involved in the process of quiescence and activation of hair follicle stem cells, energy metabolism can also affect hair follicle stem cell activity. In this regard, the role of mitochondria, energy-generating organelles, in hair follicle stem cells should be emphasized.

Keywords: energy metabolism, hair follicle stem cells, mitochondria

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