To evaluate the hair growth modulatory properties, we offer to investigate the following parameters:

• Increase/decrease of hair shaft elongation
• Changes in the rate of proliferation and apoptosis of hair matrix-resident cells
• Hair follicle cycle staging
• Changes in the expression of various receptors involved in the regulation of the switch anagen to catagen

For this assessment, only micro-dissected follicles in the active growing phase of the hair cycle (i.e. anagen VI)
can be used. Consequently, the model allows to monitor exclusively the switch between the active (anagen)
versus the involution (catagen) phase.

The following parameters can be investigated:

• Melanin, detected in the hair bulb region
• Morphology and distribution of hair follicle melanocytes

Various external factors can induce a premature transition from the anagen to the catagen phase.
The stress increase in the hair follicle is monitored by quantifying free radicals in the follicle bulb region.