Reversal of the hair loss phenotype by modulating the estradiol-ANGPT2 axis in the mouse model of female pattern hair loss.

BACKGROUND: Despite high demand for a remedy, the treatment options for female pattern hair loss (FPHL) are limited. FPHL is frequent in postmenopausal women. In ovariectomized (OVX) mice, which lack β-estradiol (E2) and manifest hair loss mimicking FPHL, E2 supplementation has been shown to increase hair density. However, the mechanism by which E2 exhibits its biological activity remains elusive.

OBJECTIVE: To identify the downstream targets of E2 in the context of FPHL pathophysiology and discover a potential therapeutic agent for the E2-dependent subtype of FPHL.

METHODS: Human dermal papilla cells (hDPCs) were cultured with E2, and a microarray analysis was performed to identify the genes regulated by E2. Using OVX mice, the identified gene product was intradermally administered and then quantitative image analysis of hair density was conducted. In silico analysis to link E2 and the identified gene was performed.

RESULTS: Global gene expression and bioinformatics analyses revealed that the genes associated with the angiopoietin-2 (ANGPT2) pathway were upregulated by E2 in hDPCs. ANGPT2 was significantly downregulated in OVX mice than in sham-operated mice (P < 0.01). Importantly, hair density was higher in OVX mice treated with ANGPT2 than in control mice (P < 0.05). In silico analysis showed DNA sequences with high possibility of estrogen receptor binding in the promoter region of ANGPT2.

CONCLUSION: The E2-ANGPT2 axis is present in hair follicles. ANGPT2 provides a strategy for the management of E2-dependent and postmenopausal subsets of FPHL.