Papilla Cells Of Hair Follicle Research Articles

Guidelines for the management of androgenetic alopecia (2010)

Guidelines for the management of androgenetic alopecia (2010) Ryoji TSUBOI, Satoshi ITAMI, Shigeki INUI, Rie UEKI, Kensei KATSUOKA, Sotaro KURATA, Takeshi KONO, Norimitsu SAITO, Motomu MANABE, Masashi YAMAZAKI, GUIDELINES PLANNING COMMITTEE FOR THE MANAGEMENT OF ANDROGENETIC ALOPECIA Department of Dermatology, Tokyo Medical University, Tokyo, Department of Regenerative Dermatology, Osaka University Graduate School of Medicine, Osaka, Department of Dermatology, Juntendo Tokyo Koto Geriatric Medical Center, Tokyo, Department of Dermatology, School of Medicine, Kitasato University, Sagamihara, Kurata Clinic, Beppu, Department of Dermatology, Nippon Medical School, Tokyo, and Department of Dermatology, Akita University Graduate School of Medicine, Akita, Japan

Molecular basis of androgenetic alopecia: From androgen to paracrine mediators through dermal papilla

Androgenetic alopecia (AGA) is characterized by vellus transformation of scalp hairs, corresponding to hair follicle miniaturization during repeated hair cycles with shortened anagen phase. This phenomenon is mediated mainly by androgen. Then, the multi-step molecular pathway of androgen can be involved in the pathogenesis of AGA. The expression of type II 5α-reductase is higher in dermal papilla cells from AGA and beard than those from other sites. On the other hand, type I 5α-reductase expression is relatively low. Next, hormone binding assays and RT-PCR demonstrated that androgen receptor (AR) expression is significantly higher in bald dermal papilla cells than non-bald cells. Additionally, AR coactivator Hic-5/ARA55 is highly expressed in dermal papilla cells of hair follicles from androgen-sensitive sites such as AGA and beard. Collectively, the enhanced expression of type II 5α-reductase, AR and Hic-5/ARA55 can upregulate sensitivity to androgen of dermal papilla cells in AGA. Furthermore, in the coculture of AR-overexpressing human dermal papilla cells from AGA and normal human keratinocytes, R1881 suppresses keratinocyte growth through androgen-inducible TGF-β1, indicating that TGF-β1 is one of the key players in pathogenesis of AGA. TGF-β2 and DKK-1 has been reported to be androgen-induced suppressor of growth of follicular epithelial cells. We expect that more pathogenic mediators will be identified in the future, enabling easier understanding of AGA pathogenesis and providing new therapeutic targets from aspect of andrology.

Biologic function of HSPC011 gene expressing in human dermal papilla cells of hair follicle

Objective To study the biologic function of hematopoietic stem/progenitor cell （HSPC） 011 gene, which was found to specifically express in the dermal papilla cells of hair follicle. Methods The plasmid pCI-neo, the pEGFP-N1 （green fluorescent protein plasmid） and the recombi- nant eukaryotic expressing plasmid pCI-neo/HSPC011 were differently transfected into the human dermal papilla cells and 3T3 cells by NucleofectorTM technique, then the effects of the expression of HSPC011 gene in these cells were investigated. Results Based on the observation of the expression of the green fluorescent protein in the human dermal papilla cells and 3T3 cells, the gene transfecting efficiency with NucleofectorTM technique was about 70% and 30%, respectively. While the HSPC011 gene expressed in the dermal papilla cells, which were immature and were similar to 3T3 cells in shape, but their aggregative behavior reserved. The activity of proliferation of human dermal papilla cells was not changed by the expression of HSPC011 gene. As for the expression of gene HSPC011, there were no effects on the biologic functions of the 3T3 cells. Conclusion The expression of HSPC011 gene might affect the differentiation of the dermal papilla cells in vitro. Key words: Hair follicle; Dermal papilla cell; Gene; HSPC011 gene; Biologic function

Apoptosis of the dermal papilla cells of hair follicle associated with the expression of gene HSPCO16 in vitro

The epithelial-mesenchymal interactions have an important role in the folliculomorphogenesis and mature hair follicle cycling. The dermal papilla, a dense aggregate of specialized dermis-derived stromal cells located at the bottom of the hair follicle, is a major component of hair, which signals the follicular epithelial cells to prolong the hair growth process. However, to date, little is known about the significance of the specific gene(s) expression in the dermal papilla cells with regard to their aggregative behaviour and hair cycling. In our previous study, the differentially gene-expressed cDNAs library had been determined by means of suppression subtractive hybridization technique between the aggregated human dermal papilla cells and control cells. Among those cDNAs library, the haematopoietic stem/progenitor cell (HSPC)-related gene HSPC016 was found. In this study, the gene HSPC016 was confirmed to express in the human dermal papilla cells by means of in situ hybridization and reverse transcriptase-polymerase chain reaction. In order to rudimentarily elucidate its biological function, a recombinant eucaryotic expressing plasmid pcDNA3.1(+)/HSPC016 was constructed and was transfected into the human dermal papilla cells and 3T3 fibroblast cells by means of Nucleofector(TM) technique (Amaxa, Cologne, Germany). Terminal deoxynucleotidyl transferase-mediated d-UTP nick end Labelling (TUNEL) assay showed that the expression of gene HSPCO16 resulted in the apoptosis of these cells, which suggested that the apoptosis of dermal papilla cells might be associated with the expression of gene HSPC016 in vitro.

Localization of sex steroid receptors in human skin.

Sex steroid hormones are involved in regulation of skin development and functions as well as in some skin pathological events. To determine the sites of action of estrogens, androgens and progestins, studies have been performed during the recent years to accurately localize receptors for each steroid hormone in human skin. Androgen receptors (AR) have been localized in most keratinocytes in epidermis. In the dermis, AR was detected in about 10% of fibroblasts. In sebaceous glands, AR was observed in both basal cells and sebocytes. In hair follicles, AR expression was restricted to dermal papillar cells. In eccrine sweat glands, only few secretory cells were observed to express AR. Estrogen receptor (ER) alpha was poorly expressing, being restricted to sebocytes. In contrast, ERbeta was found to be highly expressed in the epidermis, sebaceous glands (basal cells and sebocytes) and eccrine sweat glands. In the hair follicle, ERbeta is widely expressed with strong nuclear staining in dermal papilla cells, inner sheath cells, matrix cells and outer sheath cells including the buldge region. Progesterone receptors (PR) staining was found in nuclei of some keratinocytes and in nuclei of basal cells and sebocytes in sebaceous glands. PR nuclear staining was also observed in dermal papilla cells of hair follicles and in eccrine sweat glands. This information on the differential localization of sex steroid receptors in human skin should be of great help for future investigation on the specific role of each steroid on skin and its appendages.