Serum levels of IGF-1 are related to human skin characteristics including the conspicuousness of facial pores.

Conspicuous facial pores are one type of serious aesthetic defects for many women. However, the mechanism(s) that underlie the conspicuousness of facial pores remains unclear. We previously characterized the epidermal architecture around facial pores that correlates with the appearance of those pores in various ethnic groups including Japanese. The goal of this study was to evaluate the possible relationships between facial pore size, the severity of impairment of epidermal architecture around facial pores and sebum output levels to investigate the possible role of IGF-1 in the pathogenesis of conspicuous facial pores. The subjects consisted of 38 healthy Japanese women (aged 22-41 years). IGF-1 was measured using immunoradiometric assay. Surface replicas were collected to compare pore sizes of cheek skin and horizontal cross-section images of cheek skin were obtained non-invasively from the same subjects using in vivo confocal laser scanning microscopy and the severity of impairment of epidermal architecture around facial pores was determined. The skin surface lipids of each subject were collected from their cheeks and lipid classes were determined using gas chromatography/flame ionization detection. The serum level of IGF-1 correlated significantly with total pore area (R = 0.36, P < 0.05), with the severity of impairment of epidermal architecture around facial pores (R = 0.43, P < 0.05) and with sebum output levels (R = 0.41, P < 0.01). The sebum output levels correlated with total pore area (R = 0.32, P < 0.05). Our study found that serum levels of IGF-1 are correlated with facial skin characteristics including facial pore size and with the severity of impairment of epidermal architecture around facial pores.

Hair follicle stem cell-targeted gene transfer and reconstitution system.

Gene transfer to hair follicle (HF) epithelium is an attractive approach for not only treating skin diseases, but also many systemic disorders. In this study, we attempted to develop a gene transfer system for HF epithelial stem cells to maximize the beneficial therapeutic effects. For persistent and stable transgene expression in HF stem cells, we transferred retroviral vectors encoding reporter genes into cultured HF stem cells. In addition, these cells were mixed with cultured dermal papilla cells and transplanted on to immunodeficient mice. We succeeded in reconstituting HFs and their appendages in which these cells harbored a transgene reporter. The transgene expression was observed in all skin epithelial compartments including the HF epithelium, sebaceous gland and epidermis. In addition, transgene expression was observed for at least 6 months. This HF stem cell-targeted gene transfer and reconstitution system provides reliable gene-function analysis and gene therapy.