The following abstract was presented at the www.aslms.org meeting in April 2005:

ABSTRACT:

LED PHOTOMODULATION INDUCED HAIR GROWTH STIMULATION

Robert Weiss, David H. McDaniel, Roy G. Geronemus, Margaret Weiss

Maryland Laser Skin & Vein Institute, Hunt Valley, MD

Laser Skin & Vein Center of Virginia, Virginia Beach, VA

Laser & Skin Surgery Center of New York, New York, NY

Background & Objective:  The ability to stimulate human scalp hair growth is well established.   Oral finasteride inhibits 5-alpha reductase (5-AR).  Topical minoxidil stimulates vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and matrix metalloproteinase (MMP-2).   LED photomodulation modulates the activity of genes in human skin.  This study investigates the effects of LED photomodulation on human dermal papillae cells (HDP) in culture and in clinical trials.  

Study Design/Materials & Methods:  Male and female HDP cells were exposed to LED arrays.  Variables included wavelength, energy, and pulse duration.  Gene expression of 5-AR, HGF, MMP-2 and others were measured using RT-PCR and microarrays.

Results:  Different protocols produced significant distinctive effects on gene expression. Relative expression of 5-AR by RT-PCR ranged from -3.6 to +2.0 depending on the LED parameters.   For example, one LED array produced VEGF (+1.8), HGF (+2.0), MMP-2 (+2.7) and 5-AR (0).   This pattern resembled minoxidil rather than finasteride and was selected for a pilot clinical trial.   Hair growth stimulation was observed.   

Conclusions: LED photomodulation using visible light can alter the expression of genes associated with stimulation of hair growth.   This effect is dependant upon treatment parameters

Published online in Wiley InterScience

(www.interscience.wiley.com).

DOI 10.1002/lsm.20164

Presented at American Society for Laser Medicine and Surgery

Annual Meeting—Orlando, April 2005.