dermal papilla cells, phytochemical, reactive oxygen species, herb-derived essential oil, hair growth factor, antioxidant, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, QD1-999

Dermal papilla cells (DPCs) are a rich source of nutrients and secrete multiple growth factors that can affect hair growth. As oxidative stress leads to hair loss in humans, it is considered to be one of the factors that can impair the function of DPCs. Herb-derived phytochemicals exhibit potent antioxidant activities; therefore, this study investigated whether a set of essential oils (lavender, lemongrass, rosemary, and chamomile oils) promote the hair-growth activity of DPCs. Intracellular reactive oxygen species (ROS) increased markedly in ultraviolet B-irradiated DPCs (50 mJ/cm2) and were efficiently blocked by essential oils. Essential oils upregulated the mRNA and protein levels of phase II enzymes (detoxifying and antioxidant), including heme oxygenase-1, NAD(P)H quinone oxidoreductase-1, and glutathione S-transferase pi. They also upregulated and activated nuclear factor E2-related factor 2, an essential transcription factor for phase II enzymes. Regarding biomarkers for hair growth, essential oils significantly increased vascular endothelial cell growth factor and insulin-like growth factor-1 mRNA levels. In conclusion, phytochemicals in essential oils enhance hair growth through ROS-scavenging activity in DPCs.