Ultraviolet Light Linked to Androgenic Alopecia "Androgenic Alopecia and Stress-Induced Premature

Senescence by Cumulative Ultraviolet Light Exposure"

Cumulative ultraviolet light exposure may induce premature hair-follicle senescence in androgenic alopecia.

Dr. C. Piérard-Franchimont, of the Department of Dermatopathology, University Medical Center Sart Tilman, Liège, Belgium, and colleagues compared the severity of androgenic alopecia with the extent of solar elastosis in 140 men with androgenic alopecia and 50 non-alopecic men.

They found that the scalp dermis was significantly thicker in the men with androgenic alopecia than in the subjects without alopecia.

This difference was due to a more severe elastosis in baldness. The researchers found that the earliest signs of elastosis due to sun exposure preceded hair thinning.

A negative exponential correlation was found between hair diameter and severity of solar elastosis (when elastosis was thicker than 0.2 mm).

Concluded Dr. Piérard-Franchimont, "Chronic ultraviolet radiation exposure of the scalp may affect the hair cycle and be one of the exogenous factors influencing negatively the progression of androgenic alopecia."

Dr. Piérard-Franchimont also commented, "The induction of stress-induced premature senescence by reactive oxygen species and micro-inflammation might be operative at the level of the follicular stem cells."