Abstract (english) | The Hair Follicle (HF) is a vital component of mammalian skin and represents a unique, highly regenerative
system that undergoes phases of rapid growth, regression, and resting periods. The hair cycling is of profound
clinical relevance since majority of the hair growth disorders occur as a result of cycle changes. The influence of
many molecules governing the formation of HF has been investigated and many of important cycle mediators have
been identified. Cellular and molecular events during cycling are controlled by a network of sequential activation of
autocrine, paracrine and endocrine signaling pathways. This implies variations in the expression or activity of the
Wnt family molecules, Fibroblast Growth Factor (FGF), Transforming Growth Factor β (TGF-β), Hedgehog pathway,
β-Catenin pathway, noggin, transcription factor Stat3, Epidermal Growth Factor (EGF), Insulin Growth Factor-1 (IGF-
1), Vascular Endothelial Growth Factor (VEGF), Thyrotropin Releasing Hormone (TRH), Polyamine, Spermidine,
Neurotrophins (NT3, NT4), prolactin, retinoids, Bone Morphogenetic Protein 4 (BMP4), cathepsin L, 17-β estradiol,
dihydrotestosterone and many others. Despite considerable progress in this area, the key elements of cycle control
have not been identified. Therefore, for the most common hair disorders several agents are available, even none
of these is curative or preventive. The one of the prime challenges of hair research is a better understanding of the
molecular controls of hair cycling and developing drug which would effectively manipulate the cycle. Future therapy
strategies will be based on new and better knowledge about the HF biology. Until than, alopecia areata, telogen
effluvium and androgenetic alopecia, will remain unsolved medical problems. |