Hypothalamic–Pituitary–Thyroid Axis Hormones Stimulate Mitochondrial Function and Biogenesis in Human Hair Follicles

The study investigated the effects of hypothalamic-pituitary-thyroid (HPT) axis hormones on mitochondrial function and biogenesis in human hair follicles. It found that hormones such as TRH, TSH, T4, and T3 increased the expression of mitochondrial proteins and enhanced mitochondrial biogenesis and activity without increasing reactive oxygen species (ROS) production. Instead, T3 and T4 reduced ROS formation, and all hormones increased the transcription of ROS scavengers. The study suggested that the neuroendocrine regulation of mitochondrial biology in hair follicles could have therapeutic potential, particularly in influencing hair growth and health. The research involved human scalp skin samples from 14 healthy middle-aged women.