Investigating changes in mitochondrial dynamics after UV irradiation

Mitochondria are dynamic, double-membrane bound organelles that are essential for cellular energy metabolism, through the production of ATP, and for maintenance of cellular homeostasis. They play a fundamental role in skin physiology. Besides providing energy for the demanding process of melanin production in melanocytes and the proliferation and differentiation of keratinocytes, two main cell types present in the skin, they are also involved in regulating several signalling pathways and controlling redox status. Skin cells are indeed constantly exposed to external stresses such as chemical compounds, pollution or UV irradiation. Many studies have highlighted the role of ultraviolet (UV) light in the development and progression of skin diseases, which are often accompanied by an enhanced production of reactive oxygen species (ROS) and mitochondrial dysfunction, particularly impaired mitochondrial dynamics. This has led to the hypothesis that mitochondria could participate in the cellular response to UV. The aim of this thesis is therefore to investigate how UV irradiation can influence mitochondrial morphology and dynamics in human melanocytes. Specifically, we exposed NHEM cells (Normal Human Epidermal Melanocytes) to increasing doses of UVB and, through high-throughput analysis, we measured their effects on several parameters of mitochondrial physiology.