A new role for neurotrophin-3: involvement in the regulation of hair follicle regression (catagen).
Nervous system and hair follicle epithelium share a common ectodermal origin, and some neurotrophins (NTs) can modulate keratinocyte proliferation and apoptosis. Therefore, it is reasonable to ask whether NTs are also involved in hair growth control. Here, we show that the expression of NT-3 and its high-affinity receptor, tyrosine kinase C, in the skin of C57BL/6 mice is strikingly hair cycle-dependent, with maximal transcript and protein expression seen during spontaneous hair follicle regression (catagen). During catagen, NT-3 and tyrosine kinase C are co-expressed by terminal deoxynucleotidyl transferase-mediated in situ nick end labeling-positive keratinocytes in the club hair and secondary germ. NT-3-overexpressing transgenic mice show precocious catagen development during the postnatal initiation of hair follicle cycling, whereas heterozygous NT-3 knockout (+/-) mice display a significant catagen retardation. Finally, NT-3 stimulates catagen development in organ culture of normal C57BL/6 mouse skin. These observations suggest that the hair follicle is both a source and target of NT-3 and that NT-3/tyrosine kinase C signaling is functionally important in the control of hair follicle regression. Therefore, tyrosine kinase C agonists and antagonists deserve systematic exploration for the management of hair growth disorders that are related to premature (alopecia/effluvium) or retarded catagen (hirsutism/hypertrichosis).
Botchkarev
V A
VA
Department of Dermatology, Charité Hospital, Humboldt University, Berlin, Germany.
Welker
P
P
Albers
K M
KM
Botchkareva
N V
NV
Metz
M
M
Lewin
G R
GR
Bulfone-Paus
S
S
Peters
E M
EM
Lindner
G
G
Paus
R
R
D000818:Animals; D017209:Apoptosis; D017931:DNA Primers / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D005786:Gene Expression Regulation / Q000502:physiology; D018859:Hair Follicle / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009414:Nerve Growth Factors / Q000235:genetics / Q000502:physiology*; D020933:Neurotrophin 3; D009924:Organ Culture Techniques; D016133:Polymerase Chain Reaction; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D020800:Receptor, Nerve Growth Factor; D020812:Receptor, trkC; D017475:Receptors, Nerve Growth Factor / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000166:cytology / Q000378:metabolism
D017931:DNA Primers; D009414:Nerve Growth Factors; D020933:Neurotrophin 3; D020800:Receptor, Nerve Growth Factor; D017475:Receptors, Nerve Growth Factor; D020794:Receptor Protein-Tyrosine Kinases; D020812:Receptor, trkC