Humans ; Finasteride/pharmacology* ; Dutasteride/pharmacology* ; 5-alpha Reductase Inhibitors/pharmacology* ; Testosterone/metabolism* ; Hair Follicle/metabolism* ; Transcriptome ; Hair/metabolism*

Antigens, CD34 ; metabolism ; Biomarkers ; metabolism ; Cell Differentiation ; physiology ; Hair Follicle ; cytology ; Humans ; Intramolecular Oxidoreductases ; metabolism ; Keratinocytes ; metabolism ; Melanins ; metabolism ; Melanocytes ; metabolism ; PAX3 Transcription Factor ; metabolism ; Stem Cells ; metabolism

OBJECTIVETo investigate the protective effect of melatonin on residual hair follicle cells of scald rats at early stage.

METHODSEighteen male Sprague-Dawley rats were randomly divided into scald group, treatment group, sham group , with 6 rats in each group. The rats in scald group and treatment group were subjected to 30% TBSA partial thickness scald on the back, and were resuscitated with balanced solution after 1 hour, while those in sham group were immersed in water at 37 degrees C for 25 s to simulate scald, and did not receive fluid replacement. Rats in treatment group were intraperitoneally injected with 10 mg/kg melatonin solution at 1 minute, 8 hours and 12 hours after scald, while those in sham group and scald group were given equal volume of 1% alcohol sodium-isotonic saline instead. Tissue samples were harvested at 6, 12 and 24 post scald hours (PSH) for determination of MDA and GSH levels. Apoptosis of residul hair follicle was detected by TUNEL method and immunohistochemistry of caspase-3.

RESULTSThe level of MDA in scald group at each time point was much higher than that in sham group (P < 0.01) and treatment group (P < 0.05), and it peaked at 12 PSH. The changes in GSH were just opposite to that of MDA. Under fluorescence microscope, the residual hair follicle cells were blue, and the apoptotic cells appeared green. The apoptosis rate in scald group at 6, 12, 24 PSH was obviously higher than that in sham (P < 0.01) and treatment groups (P < 0.05), which was (20.2 +/- 3.4)% vs (4.3 +/- 2.3)% vs (10.9 +/- 3.2)%, (31.2 +/- 3.6)% vs (5.1 +/- 2.5)% vs (19.1 +/- 3.7)%, (22.4 +/- 2.7)% vs (4.1 +/- 2.4)% vs (13.1 +/- 3.4)%, respectively. The score of caspase-3 positive cell in scald group was higher than those in sham group (P < 0.01) and treatment group (P < 0.05).

CONCLUSIONSThere is obvious correlation between oxidative stress and apoptosis rate of hair follicle cells in rats with partial thickness scald. Early administration of melatonin may have anti-apoptosis ability for residual hair follicle cells by attenuation of oxidative stress.

Animals ; Apoptosis ; Burns ; drug therapy ; metabolism ; Hair Follicle ; cytology ; metabolism ; Male ; Melatonin ; therapeutic use ; Oxidative Stress ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo explore the differences of PDGF and EGF expression in the wound healing between fatal and adult.

METHODSWith the established animal model of fetal scarless healing and the adult samples, an immunohistochemical technique was used to evaluate the expression of PDGF and EGF in the normal adult skin, normal fetal skin, and the process of their wound healing.

RESULTS1. The expression of the PDGF was not found in the fetal skin, but a mild amount of the PDGF was shown in the epidermis and the upper dermal layer 12 hours and 1 day after the wounding process. In the normal adult skin, expression of PDGF was shown in the dermal fibroblasts, macrophagocytes and blood capillaries, and a strong expression was presented during its wound healing process. 2. In the fetal skin, the expression of the EGF was seen in the epidermis, hair follicles, sebaceous glands and sweat glands, but there were no markedly changes during the wound healing. In the adult skin, a positive stain of the EGF was shown in the basal layer of the epidermis while the mild stain in hair follicles and sweat glands. The level of the expression became gradually decreasing with the time going in the wounded adult skin.

CONCLUSIONThe different expression of growth factors between fetal and adult skin in wound healing may be one of the important reasons that the fetal wound could produce scarless healing.

Adult ; Epidermal Growth Factor ; metabolism ; Epidermis ; metabolism ; Fetus ; Fibroblasts ; metabolism ; Hair Follicle ; metabolism ; Humans ; Platelet-Derived Growth Factor ; metabolism ; Skin ; injuries ; metabolism ; Sweat Glands ; metabolism ; Wound Healing

OBJECTIVETo observe the hair follicle regeneration after subcutaneous implantation of hair follicle cell mixture in nude mice.

METHODSThe hair papilla cells, dermal sheath cells, outer root sheath and fibroblasts of human scalp were mixed with the hair follicle epithelial cells and implanted subcutaneously in nude mice to observe the regeneration of the hair follicle.

RESULTS AND CONCLUSIONFormation of intact hair follicle-like structures was observed in the skin sections of the recipient nude mice, suggesting the feasibility of this approach for hair follicle regeneration in vivo.

Animals ; Cell Transplantation ; Hair Follicle ; cytology ; metabolism ; physiology ; transplantation ; Humans ; Injections, Subcutaneous ; Mice ; Mice, Nude ; Regeneration ; Skin Pigmentation ; Time Factors

BACKGROUND: AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase that plays a pivotal role in the balance of cellular energy metabolism. Recent studies have reported that AMPK has numerous roles in physiological conditions, and dysregulation of AMPK induces pathological processes and diseases. However, the role of AMPK and its activators have not yet been studied in the context of hair growth regulation. OBJECTIVE: To investigate the effects of metformin on dermal papilla (DP) and outer root sheath (ORS) cells, as well as the role of the AMPK pathway in hair growth. METHODS: We evaluated whether metformin, a well-known AMPK activator, had any beneficial effects on hair growth. In addition, to evaluate the molecular and cellular mechanisms that were involved, protein levels of AMPK and β-catenin were analyzed. RESULTS: Metformin increased the cellular proliferation of human DP and ORS cells. Ki-67 expression was also significantly increased after metformin treatment in the ex vivo hair follicle organ culture. Furthermore, DP and ORS cells treated with metformin had a significant increase in AMPK phosphorylation, which in turn suppressed β-catenin degradation and enhanced its nuclear accumulation. CONCLUSION: We demonstrated that metformin promoted hair growth via the AMPK/β-catenin signaling pathway in vitro with DP and ORS cells. The hair-promoting effects of AMPK activators may potentially be used for the treatment of alopecia, and further investigation will be needed in the future.
Alopecia ; AMP-Activated Protein Kinases ; beta Catenin ; Cell Proliferation ; Energy Metabolism ; Hair Follicle ; Hair ; Humans ; In Vitro Techniques ; Metformin ; Organ Culture Techniques ; Pathologic Processes ; Phosphorylation ; Protein Kinases

OBJECTIVETo investigate whether the suppression of Wnt10b by siRNA could prevent the development of hair follicle in the cultured rat embryonic skin.

METHODSsiRNA-Wnt10b was synthesized by chemosynthesis method. The dorsal skin of SD rat at embryos were cultured in DMEM in the presence of different percentage of interfering RNA targeting Wnt10b. Wnt10b/beta-catenin expression was analyzed by real-time PCR everyday and by Western blot on the third day. The cultured embryonic skin underwent paraffin embedding, section, HE staining on the third day,in which the number of de novo hair follicle was calculated and statistically analyzed.

RESULTSWnt10b gene in the cultured embryonic skin could be knocked down with the siRNA-based method. Beta-catenin mRNA was not greatly influenced by the downregulation of Wnt10b mRNA. The number of de novo hair follicle placode in cultured embryonic skin decreased, along with the downregulation of Wnt10b and beta-catenin proteins expression.

CONCLUSIONSThe downregulation of Wnt10b mRNA and protein by siRNA reduces the number of de novo hair follicle placode in the cultured rat embryonic skin. Wnt10b may control cytoplasm beta-catenin concentration at the protein level.

Animals ; Hair Follicle ; embryology ; metabolism ; RNA, Messenger ; genetics ; RNA, Small Interfering ; genetics ; Rats ; Skin ; embryology ; metabolism ; Tissue Culture Techniques ; Wnt Proteins ; genetics ; metabolism ; beta Catenin ; metabolism

OBJECTIVETo explore the effect of tacrolimus on murine hair follicle cycle.

METHODHematoxylin-eosin dyeing and reverse transcription-polymerase chain raction techniques were used.

RESULTSFive days after depilation, the hair follicles in both the tacrolimus group and the minoxidil group was in anagen V, while that in the vaseline group was in anagen III. vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were detected in back skin in both the tacrolimus group and the minoxidil group, but not in the vaseline group.

CONCLUSIONTacrolimus can promote the growth of hair by stimulating the hair follicle to enter anagen V in mice, which may be explained by the effects of VEGF and HGF.

Animals ; Hair Follicle ; drug effects ; physiology ; Hepatocyte Growth Factor ; metabolism ; Mice ; Mice, Inbred C57BL ; Minoxidil ; pharmacology ; Skin ; drug effects ; metabolism ; Tacrolimus ; pharmacology ; Vascular Endothelial Growth Factor A ; metabolism

OBJECTIVETo establish a simple method for isolating and culturing follicular papilla cells from rat vibrissae.

METHODSThe intact follicles were obtained and digested in 0.2% collagenase I with agitation on a rotary stirrer at 100 r/min at 37 degrees C; for 3 h. The suspension was centrifuged at 300 r/min and the papilla cells were collected and suspended in DMEM for cell culture. The adhesion efficiency of the dermal papilla cells was evaluated and compared with that of the cells obtained by microdissection.

RESULTS AND CONCLUSIONThe described procedure allowed efficient and rapid isolation of the dermal papilla cells from rat vibrissae and ensured improved adhesion of the dermal papillae and outgrowth of the cells with reduced labor and risk of contamination. The cells obtained with this procedure were positive for alpha-smooth muscle actin staining.

Animals ; Cell Culture Techniques ; Cell Proliferation ; Cell Separation ; methods ; Cells, Cultured ; Hair Follicle ; cytology ; metabolism ; Rats ; Rats, Wistar ; Vibrissae ; cytology ; metabolism

OBJECTIVETo investigate the effect of substance P (SP) on the migration and differentiation of epidermal stem cells (ESCs) to hair follicle, and its mechanism.

METHODSESCs were cultured in vitro, and confirmed by positive staining of K19 and integrin beta1 with immunohistochemistry. SP was added into the culture of ESCs which were labelled with 5-BrdU, and the cell cultures were divided into control, 10(-5) mol/L SP, 10(-6) mol/L SP, and 10(-7) mol/L SP groups according to the different doses of SP addition. Cell suspension (0.3 ml) containing SP was injected into the dermis in the back of nude mice. Repeated injection of the equal amount of cell suspension in the same place was carried out on 4, 7, 10 and 14 days after first injection. The cells in control group received the same treatment but without SP. The skin specimens in the area of cell culture injection and the normal skin remote from cell injection were harvested for the histological examination and hair follicle counting by immunohistochemistry and electronmicroscope 28 days after injections.

RESULTSHair follicles in scattered distribution were observed in 10(-5) mol/L SP group,but some of them were defective in development. Hypoplasic hair follicle and a few hair follicles with distinct structure were observed in 10(-5) mol/L SP group. Large amounts of hair follicles with distinct structure in deep dermis and subcutaneous tissue were observed in 10(-6) mol/L SP, 10(-7) mol/L SP groups, and some of them showed positive staining of brown BrdU in the hair root, and most of them showed positive staining of brown beta-catenin, but a few of them showed developmental defect. In contrast, hypoplasia of hair follicle underneath epidermis and deep layer of dermis with positive staining of brown BrdU and beta-catenin in epidermis were observed in control group. The number of hair follicles in 10(-6)mol/L SP, 10(-7) mol/L SP groups [(1.9 +/- 1.2 ), (1.3 +/- 0.8)] was obviously less than that in control group [(10. 5 +/- 1.2), P < 0.01].

CONCLUSIONSP can induce ESCs to migrate from the basal layer into hair follicle, and this effect is dependent on the SP concentration. SP can also elevate the expression of beta-catenin in ESCs,which induces its differentiation to hair follicles.

Animals ; Cell Differentiation ; Cell Movement ; Cells, Cultured ; Epidermis ; cytology ; Hair Follicle ; cytology ; Rats ; Rats, Wistar ; Stem Cells ; cytology ; Substance P ; metabolism