Limitations of human occipital scalp hair follicle organ culture for studying the effects of Minoxidil as a hair growth enhancer
Exp Dermatol. 2004 Oct;13(10):635-42.
Magerl M1, Paus R, Farjo N, Müller-Röver S, Peters EM, Foitzik K, Tobin DJ.
Systemic administration of Minoxidil can promote hair growth. However, it is not yet known why only some individuals respond with dense hair regrowth when Minoxidil is applied topically and currently we are unable to pre-select Minoxidil responders. Previously published work on hair growth-promoting effects of Minoxidil in the lab is largely contradictory. This is complicated further by the assumption that minoxidil’s systemic hair growth effects may be reliably assessed in the short-term culture of hair follicles in their growing phase.
The above published study was a collaboration by Farjo Hair Institute, Professor Desmond Tobin and his team in the Dept. of Biomedical Sciences at the University of Bradford and the Dept. of Dermatology, University Hospital Eppendorf, Hamburg, Germany.
In the experiments used in this study system, a statistically significant enhancement of hair shaft elongation rate or an increase in anagen (the hair’s growing phase) duration by Minoxidil could not be detected. Even multiple attempts to refine the culture protocol the use of an unparalleled large number of hair follicles, data pooling, and extended analysis failed to reveal any sufficiently reproducible, significant Minoxidil effect with respect to hair shaft elongation or anagen duration in vitro.
Therefore, Minoxidil’s accepted hair growth promoting effect – in a sub-population of human individuals in vivo – may not be appreciated in this hair follicle organ culture system (which studies already maximally growing anagen follicles). This may be especially so if hair follicles from donors are employed that have not been pre-selected for Minoxidil responsiveness