Exploring the Brain-Skin Connection: Leads and Lessons from the Hair Follicle

The document from October 1, 2016, discusses the resurgence of interest in the physiological connection between the central nervous system (CNS) and the skin, particularly focusing on the role of human scalp hair follicles (HFs) in this "brain-skin connection." It highlights the discovery that scalp HFs are not only targets for neurohormones, neurotrophins, and neuropeptides but also significant sources of these neuromediators. The essay emphasizes that HFs act as miniorgans that use neurohormones to regulate their own growth, hair production, pigmentation, energy metabolism, and immune responses. Additionally, it suggests that studying HFs can reveal new, clinically relevant aspects of neurohormones in skin physiology and places the skin epithelium at the forefront of research into the interactions between the CNS and skin, marking a shift from the traditional CNS-centric perspective in dermatology.