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

Caesalpinia sappan L., belonging to the family Leguminosae, is a medicinal plant that is distributed in Southeast Asia. The dried heartwood of this plant is used as a traditional ingredient of food, red dyes, and folk medicines in the treatment of diarrhea, dysentery, tuberculosis, skin infections, and inflammation. Brazilin is the major active compound, which has exhibited various pharmacological effects, including anti-platelet activity, anti-hepatotoxicity, induction of immunological tolerance, and anti-inflammatory and antioxidant activities. The present study aimed to evaluate the antioxidant activity and expression of antioxidant enzymes of C. sappan L. extract and its major compound, brazilin, in human epidermal keratinocytes exposed to UVA irradiation. Our results indicated that C. sappan L. extract reduced UVA-induced HO production via GPX7 activation. Moreover, brazilin exhibited antioxidant effects that were similar to those of C. sappan L. via glutathione peroxidase 7 (GPX7), suggesting that C. sappan L. extract and its natural compound represent potential treatments for oxidative stress-induced photoaging of skin.
Antioxidants ; pharmacology ; Benzopyrans ; pharmacology ; Caesalpinia ; chemistry ; Humans ; Hydrogen Peroxide ; toxicity ; Keratinocytes ; cytology ; drug effects ; enzymology ; radiation effects ; Oxidative Stress ; drug effects ; radiation effects ; Peroxidases ; genetics ; metabolism ; Plant Extracts ; pharmacology ; Protective Agents ; pharmacology ; Ultraviolet Rays

Silver-containing preparations are widely used in the management of skin wounds, but the effects of silver ions on skin wound healing remain poorly understood. This study investigated the effects of silver ions (Ag) on the proliferation of human skin keratinocytes (HaCaT) and the production of intracellular reactive oxygen species (ROS). After treating HaCaT cells with Ag and/or the active oxygen scavenger N-acetyl cysteine (NAC), cell proliferation and intracellular ROS generation were assessed using CCK-8 reagent and DCFH-DA fluorescent probe, respectively. In addition, 5-bromo-2-deoxyUridine (BrdU) incorporation assays, cell cycle flow cytometry, and proliferating cell nuclear antigen (PCNA) immunocytochemistry were conducted to further evaluate the effects of sub-cytotoxic Ag concentrations on HaCaT cells. The proliferation of HaCaT cells was promoted in the presence of 10 and 10 mol/L Ag at 24, 48, and 72 h. Intracellular ROS generation also significantly increased for 5-60 min after exposure to Ag. The number of BrdU-positive cells and the presence of PCNA in HaCaT cells increased 48 h after the addition of 10 and 10 mol/L Ag, with 10 mol/L Ag markedly increasing the cell proliferation index. These effects of sub-cytotoxic Ag concentrations were repressed by 5 mmol/L NAC. Our results suggest that sub-cytotoxic Ag concentrations promote the proliferation of human keratinocytes and might be associated with a moderate increase in intracellular ROS levels. This study provides important experimental evidence for developing novel silver-based wound agents or dressings with few or no cytotoxicity.
Apoptosis ; drug effects ; Cell Line ; Cell Proliferation ; drug effects ; Fluorescent Antibody Technique ; Humans ; Keratinocytes ; cytology ; drug effects ; Proliferating Cell Nuclear Antigen ; metabolism ; Reactive Oxygen Species ; metabolism ; Silver ; pharmacology

Skin wound healing is a complex event, and interrupted wound healing process could lead to scar formation. The aim of this study was to examine the morphological changes of scar tissue. Pathological staining (HE staining, Masson's trichrome staining, methenamine silver staining) was used to evaluate the morphological changes of regenerating epidermis in normal skin and scar tissue, and immunofluorescence staining to detect the expression of collagen IV, a component of basement membrane (BM), and the expression of integrinβ4, a receptor for BM laminins. Additionally, the expression of CK14, CK5, and CK10 was measured to evaluate the proliferation and differentiation of keratinocytes in normal skin and scar tissue. The results showed that the structure of the skin was histologically changed in scar tissue. Collagen IV, expressed under the epidermis of normal skin, was reduced distinctly in scar tissue. Integrinβ4, expressed in the basal layer of normal skin, was found absent in the basal layer of scar tissue. Additionally, it was found that keratinocytes in scarring epidermis were more proliferative than in normal skin. These results indicate that during the skin wound healing, altered formation of BM may affect the proliferation of keratinocytes, reepithelial and tissue remodeling, and then result in scar formation. Thus, remodeling BM structure during wound repair may be beneficial for improving healing in cutaneous wounds during clinical practice.
Adolescent ; Adult ; Cicatrix ; metabolism ; pathology ; Collagen Type IV ; metabolism ; Female ; Humans ; Integrin beta4 ; metabolism ; Keratinocytes ; cytology ; metabolism ; pathology ; Male ; Skin ; cytology ; metabolism ; pathology

OBJECTIVETo observe the effects of estrogen on epidermis growth of mice and proliferation of keratinocytes (human epidermal cell line HaCaT), and to explore its mechanism.

METHODS(1) Five adult C57BL/6 mice in estrus cycle were identified by vaginal exfoliative cytology diagnosis and set as estrus group, while another 5 adult C57BL/6 mice with ovary resected before sexual development were set as ovariectomized group. The full-thickness skin from the tail root of mice in two groups were collected. The thickness of epidermis was observed and measured after HE staining. The distribution of proliferating cell nuclear antigen (PCNA)-positive cells in epidermis was observed by immunohistochemical staining, the number of which was counted. (2) HaCaT cells in logarithmic growth phase were cultured with RPMI 1640 nutrient solution containing 10% fetal bovine serum, and they were divided into negative control group (NC), pure estradiol group (PE), protein kinase B (Akt) inhibitor group (AI), and extracellular signal-regulated kinase (ERK) inhibitor group (EI) according to the random number table, with 20 wells in each group. To nutrient solution of each group, 1 μL dimethyl sulfoxide, 1 μL 17β-estradiol (100 nmol/L), 1 μL LY294002 (10 μmol/L), and 1 μL PD98059 (30 μmol/L) were added in group NC, group PE, group AI, and group EI respectively, and the last two groups were added with 1 μL 17β-estradiol (100 nmol/L) in addition. At post culture hour (PCH) 0 (immediately after culture), 24, 48, 72, 5 wells of cells from each group were collected to detect the proliferation activity of cells by cell counting kit 8 and microplate reader. (3) HaCaT cells in logarithmic growth phase were collected, grouped, and treated with the above-mentioned methods, with 3 wells in each group. At PCH 72, cell cycle distribution was detected by flow cytometer to calculate proliferation index (PI) of cells. (4) HaCaT cells in logarithmic growth phase were collected, grouped, and treated with the above-mentioned methods, with 3 dishes in each group. At PCH 72, the protein levels of phosphorylated Akt (p-Akt), phosphorylated ERK (p-ERK), and PCNA were determined with Western blotting. The cell experiments were repeated for 3 times. Data were processed with t test, one-way analysis of variance, analysis of variance of factorial design, and LSD test.

RESULTS(1) The epidermis thickness of mice in ovariectomized group was (33.5±3.0) μm, which was obviously thinner than that in estrus group [(51.4±3.1) μm, t=20.7, P<0.01]. The PCNA-positive cells mainly aggregated in the basal layer of epidermis of mice in two groups. The number of PCNA-positive cells in epidermis of mice in ovariectomized group was 37±12 per 200 fold visual field, obviously fewer than that in estrus group (96±15 per 200 fold visual field, t=15.3, P<0.01). (2) During PCH 0 to 48, there were no significant differences in the proliferation activity of cells between group PE and group NC (with P values above 0.05). At PCH 72, compared with that in group NC, the proliferation activity of cells in group PE was obviously increased (P<0.01). The proliferation activity of cells in groups AI and EI was obviously lower than that in the previous two groups (with P values below 0.01). (3) Compared with that in group NC [(51.6±1.1)%], the PI of cells in group PE was obviously increased [(58.5±0.8)%, P<0.05]. The PI values of cells in groups AI and EI were (34.9±0.8)% and (48.2±0.4)% respectively, both obviously lower than those in the previous two groups (with P values below 0.01). (4) Compared with that of group NC (0.566±0.034), the protein level of p-Akt in cells of group PE was significantly increased (1.048±0.077, P<0.01). Compared with that of group PE, the protein level of p-Akt was obviously decreased in cells of groups AI and EI (respectively 0.682±0.095 and 0.672±0.019, with P values below 0.01). Compared with that of group NC (0.469±0.013), the protein level of p-ERK obviously increased in cells of groups PE, AI, and EI (respectively 1.064±0.089, 1.010±0.038, 0.778±0.065, with P values below 0.01). The protein level of p-ERK in cells of group EI was obviously lower than that in group PE (P<0.01). Compared with that of group NC (0.386±0.053), the protein level of PCNA was obviously increased in cells of group PE (0.743±0.043, P<0.01). The protein levels of PCNA in cells of groups AI and EI were 0.264±0.019 and 0.223±0.065 respectively, both obviously lower than those in the previous two groups (with P values below 0.01).

CONCLUSIONSLack of estrogen damages the growth ability of epidermis of mice. Estrogen (17β-estradiol) can promote the proliferation of HaCaT cells by increasing the expression of PCNA via activating ERK/Akt signaling pathway.

Animals ; Cell Cycle ; Cell Line ; Cell Proliferation ; drug effects ; Epidermis ; cytology ; drug effects ; growth & development ; Estradiol ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; antagonists & inhibitors ; Female ; Humans ; Keratinocytes ; cytology ; drug effects ; Mice ; Mice, Inbred C57BL ; Phosphorylation ; Proliferating Cell Nuclear Antigen ; metabolism ; Proto-Oncogene Proteins c-akt ; antagonists & inhibitors ; Signal Transduction

OBJECTIVE: In order to investigate the interaction between the cytokines and keratinocyte and determine the role of cytokines in hyperproliferative of chronic otitis media with cholesteatoma, we observe the expression of matrix metalloproteinase 9 (MMP9), vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF) and its receptor (KGFR) in middle ear cholesteatoma. METHOD: We examined the expression of MMP9, VEGF, KGF, KGFR and Ki-67 by immunohistochemistry in 50 specimens from chronic otitis media with cholesteatoma and 15 specimens from the normal skin of external auditory meatus. Ki-67 as an evaluation of cholesteatoma proliferation markers were used to detect the keratinocyte proliferative activity. RESULT: (1) The expression of VEGF and MMP9 in cholesteatoma specimens was higher than normal skin, and the difference was statistically significant (t = 4.914, P < 0.01; t = 3.284, P < 0.01). (2) The expression of KGF and KGFR in middle ear tissues was higher than normal skin, and the difference was statistically significant (t = 4.814, P < 0.01; t = 3.104, P < 0.01); The expression of KGF and KGFR increased, and the expression of Ki-67 also correspondly increased in the cholesteatoma. (3) In the tissue MMP9 and VEGF were positive. Mean optical density increased as well. KGF expression also increased accordingly. CONCLUSION MMP9, VEGF, KGF and KGFR proteins played an important role in hyperproliferation of cholesteatoma tissues. VEGF, MMP9 and KGF had a synergistic effect in hyperproliferation of cholesteatoma tissues.
Cholesteatoma, Middle Ear ; pathology ; Cytokines ; metabolism ; Ear Canal ; metabolism ; Ear, Middle ; metabolism ; Fibroblast Growth Factor 7 ; metabolism ; Humans ; Immunohistochemistry ; Keratinocytes ; cytology ; Ki-67 Antigen ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Otitis Media ; pathology ; Receptor, Fibroblast Growth Factor, Type 2 ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism

BACKGROUNDShikonin is a major active chemical component extracted from Lithospermi Radix, an effective traditional herb in various types of wound healing. Shikonin can accelerate granulomatous tissue formation by the rat cotton pellet method and induce neovascularization in granulomatous tissue. The purpose of the study was to investigate its mechanism of action in human skin cells.

METHODSMTS assay was used to measure cell growth. The collagen type I (COL1 ) mRNA expression and procollagen type I C-peptide (PIP) production were detected by real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Immunofluorescence and western blot analyses were carried out to investigate nuclear factor-κB (NF-κB) signaling pathway. Cell-based proteasome activity assay was used to determine proteasome activity.

RESULTSIn this study, we found that 10 μmol/L shikonin stimulated the growth of normal human keratinocytes and 1 μmol/L shikonin promoted growth of human dermal fibroblasts. However, shikonin did not directly induce COL1 mRNA expression and PIP production in dermal fibroblasts in vitro. In addition, 1 μmol/L shikonin inhibited translocation of NF-κB p65 from cytoplasm to nucleus induced by tumor necrosis factor-α stimulation in dermal fibroblasts. Furthermore, shikonin inhibited chymotrypsin-like activity of proteasome and was associated with accumulation of phosphorylated inhibitor κB-α in dermal fibroblasts.

CONCLUSIONSThese results suggested that shikonin may promote wound healing via its cell growth promoting activity and suppress skin inflammation via inhibitory activity on proteasome. Thus, shikonin may be a potential therapeutic reagent both in wound healing and inflammatory skin diseases.

Cell Proliferation ; drug effects ; Cells, Cultured ; Enzyme-Linked Immunosorbent Assay ; Fibroblasts ; drug effects ; Humans ; Keratinocytes ; drug effects ; NF-kappa B ; metabolism ; Naphthoquinones ; pharmacology ; Polymerase Chain Reaction ; Proteasome Endopeptidase Complex ; drug effects ; Skin ; cytology

OBJECTIVETo observe the effect of shikonin on the proliferation of human keratinocytes induced by IL-17 and secretion of chemokines, in order to discuss the mechanism of Shikonin in the treatment of psoriasis.

METHODIn vitro cultured HaCaT cells were stimulated by IL-17A (200 μg x L(-1)) and mixed with different concentrations (2, 1 mg x L(-1)) of shikonin for 24 hours. The cell proliferation was detected by CCK-8 assay. Cell secretion inflammatory factor interleukin-23 (IL-23) was detected by ELISA. The expressions of intracellular chemokines CXCL1, CXCL2, CCL20 and 6-defensin 4 (DEFB4) were detected by Real-time PCR.

RESULTShikonin (2,1 mg x L(-1)) could distinctly inhibit HaCaT cell proliferation induced by IL-17A, with statistical difference (P < 0.01). Each shikonin group showed decreases in the secretion of IL-23 and inhibition in expressions of intracellular CXCL1, CXCL2, CCL20 and DEFB4.

CONCLUSIONShikonin could inhibit HaCaT cells proliferation induced by IL-17 and secretion of relevant cytokines and recruit leukocytes by inhibiting chemokines, so as to show the effect in treating psoriasis.

Cell Line ; Cell Proliferation ; drug effects ; Chemokines ; genetics ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Interleukin-17 ; genetics ; metabolism ; Keratinocytes ; cytology ; drug effects ; metabolism ; Naphthoquinones ; pharmacology

Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.
Adult ; Cell Proliferation ; Chemokine CXCL12 ; genetics ; Epidermal Cells ; Epidermis ; pathology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Fibroblasts ; metabolism ; Gene Expression Regulation ; Humans ; Keratinocytes ; cytology ; pathology ; Signal Transduction ; Skin Diseases ; genetics ; pathology

The deubiquitinating enzyme ubiquitin specific peptidase 15 (USP15) is regarded as a regulator of TGFβ signaling pathway. This process depends on Smad7, the inhibitory factor of the TGFβ signal, and type I TGFβ receptor (TβR-I), one of the receptors of TGFβ. The expression level of USP15 seems to play vital roles in the pathogenesis of many neoplasms, but so far there has been no report about USP15 in psoriasis. In this study, immunohistochemical staining of USP15, TβR-I and Smad7 was performed in 30 paraffin-embedded psoriasis specimens and 10 normal specimens to investigate the expression of USP15, TβR-I and Smad7 in psoriasis and to explore the relevance among them. And USP15 small interfering RNA (USP15 siRNA) was used to transfect Hacat cells to detect the mRNA expression of TβR-I and Smad7. Of 30 cases of psoriasis in active stage, 28, 24 and 26 cases were positive for USP15, TβR-I and Smad7 staining, respectively. The positive rates of USP15 and Smad7 were significantly higher in psoriasis specimens than in normal skin specimens (44.1%±26.0% vs. 6.1%±6.6%, 47.2%±27.1% vs. 6.6%±7.1%), and positive rate of TβR-I (20.3%±22.2%) in psoriasis was lower than that in normal skin specimens (46.7%±18.2%). There was a significant positive correlation between USP15 and Smad7 expression, and significant negative correlations between USP15 and TβR-expression, an I d between TβR- and Smad7 expression I in psoriasis. After transfection of USP15 siRNA in Hacat cells, the expression of TβR-mRNA was up I -regulated and that of Smad7 was down-regulated. It is concluded that USP15 may play a role in the pathogenesis of psoriasis through regulating the TβR-I/Smad7 pathway and there may be other cell signaling pathways interacting with USP15 to take part in the development of psoriasis.
Adult ; Cell Line ; Female ; Gene Expression ; Humans ; Immunohistochemistry ; Keratinocytes ; cytology ; metabolism ; Male ; Middle Aged ; Protein-Serine-Threonine Kinases ; biosynthesis ; genetics ; Psoriasis ; genetics ; metabolism ; RNA Interference ; Receptors, Transforming Growth Factor beta ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; genetics ; Skin ; metabolism ; Smad7 Protein ; biosynthesis ; genetics ; Ubiquitin-Specific Proteases ; biosynthesis ; genetics ; Young Adult