OBJECTIVE: To investigate the effectiveness and preliminary mechanisms of icariin (ICA) in enhancing the reparative effects of adipose-derived stem cells (ADSCs) on skin radiation damagies in rats. METHODS: Twelve SPF-grade Sprague Dawley rats [body weight (220±10) g] were subjected to a single dose of 10 Gy X-ray irradiation on a 1.5 cm×1.5 cm area of their dorsal skin, with a dose rate of 200 cGy/min to make skin radiation damage model. After successful modelling, the rats were randomly divided into 4 groups ( n=3), and on day 2, the corresponding cells were injected subcutaneously into the irradiated wounds: group A received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL), group B received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL)+1 μmol/L ICA (0.1 mL), group C received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL) pretreated with a hypoxia-inducible factor 2α (HIF-2α) inhibitor+1 μmol/L ICA (0.1 mL), and group D received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL) pretreated with a Notch1 inhibitor+1 μmol/L ICA (0.1 mL). All treatments were administered as single doses. The skin injury in the irradiated areas of the rats was observed continuously from day 1 to day 7 after modelling. On day 28, the rats were sacrificed, and skin tissues from the irradiated areas were harvested for histological examination (HE staining and Masson staining) to assess the repair status and for quantitative collagen content detection. Immunohistochemical staining was performed to detect CD31 expression, while Western blot and real-time fluorescence quantitative PCR (qRT-PCR) were used to measure the protein and mRNA relative expression levels of vascular endothelial growth factor (VEGF), platelet-derived growth factor BB (PDGF-BB), fibroblast growth factor 2 (FGF-2), interleukin 10 (IL-10), transforming growth factor β (TGF-β), HIF-2α, and Notch1, 2, and 3. RESULTS: All groups exhibited skin ulcers and redness after irradiation. On day 3, exudation of tissue fluid was observed in all groups. On day 7, group B showed significantly smaller skin injury areas compared to the other 3 groups. On day 28, histological examination revealed that the epidermis was thickened and the dermal fibers were slightly disordered with occasional inflammatory cell aggregation in group A. In group B, the epidermis appeared more normal, the dermal fibers were more orderly, and there was an increase in new blood vessels without significant inflammatory cell aggregation. In contrast, groups C and D showed significantly increased epidermal thickness, disordered and disrupted dermal fibers. Group B had higher collagen fiber content than the other 3 groups, and group D had lower content than group A, with significant differences ( P<0.05). Immunohistochemical staining showed that group B had significantly higher CD31 expression than the other 3 groups, while groups C and D had lower expression than group A, with significant differences ( P<0.05). Western blot and qRT-PCR results indicated that group B had significantly higher relative expression levels of VEGF, PDGF-BB, FGF-2, IL-10, TGF-β, HIF-2α, and Notch1, 2, and 3 proteins and mRNAs compared to the other 3 groups ( P<0.05). CONCLUSION ICA may enhance the reparative effects of ADSCs on rat skin radiation damage by promoting angiogenesis and reducing inflammatory responses through the HIF-2α-VEGF-Notch signaling pathway.
Animals ; Rats, Sprague-Dawley ; Skin/pathology* ; Rats ; Vascular Endothelial Growth Factor A/genetics* ; Basic Helix-Loop-Helix Transcription Factors/genetics* ; Signal Transduction ; Flavonoids/pharmacology* ; Adipose Tissue/cytology* ; Stem Cells/cytology* ; Receptors, Notch/metabolism* ; Radiation Injuries, Experimental/metabolism* ; Wound Healing/drug effects* ; Male

Objective To investigate the effect of liquid-liquid phase separation(LLPS)of YTH domain family protein 2(YTHDF2)on the sodium arsenite-induced malignant transformation of skin cells,providing a new intervention target for the prevention and control of sodium arsenite-induced carcinogenesis.Methods The HaCaT cell model of malignant transformation was constructed by continuous treatment with 1 μmol/L sodium arsenite for 22 weeks,including cells with normal YTHDF2 LLPS(YTHDF2-wt)and cells with inhibited YTHDF2 LLPS(YTHDF2-mut).Confocal microscopy was employed to observe and characterize the LLPS droplets formed by YTHDF2 during sodium arsenite-induced malignant transformation of skin cells.Cell proliferation,scratch healing,and colony formation assays were performed to detect malignant phenotypes.Western blotting,quantitative reverse transcription PCR,and immunofluorescence experiments were conducted to examine the effects of YTHDF2 LLPS on the mRNA and protein levels of phosphatase and tensin homolog deleted on chromosome ten(PTEN)during sodium arsenite-induced malignant transformation of skin cells.Results After 4 weeks of sodium arsenite treatment,LLPS droplets of YTHDF2 appeared in YTHDF2-wt cells,and the number of droplets gradually increased as the treatment time was prolonged(F=35.252,P<0.001),while no phase-separated droplets were observed in YTHDF2-mut cells.Compared with YTHDF2-mut cells,YTHDF2-wt cells showed enhanced proliferation at the time points of 48 h(t=3.654,P=0.006)and 72 h(t=5.458,P<0.001)after 22 weeks of sodium arsenite treatment.The scratch healing rate of YTHDF2-wt cells was increased at the 8th(t=12.137,P<0.001)and 22th(t=4.484,P=0.011)weeks of sodium arsenite treatment.The number of colonies formed by YTHDF2-wt cells was higher at the 4th(t=3.365,P=0.027),8th(t=5.580,P=0.005),and 22th(t=3.328,P=0.029)weeks of sodium arsenite treatment.Compared with YTHDF2-mut cells,YTHDF2-wt cells showed down-regulated protein(t=-3.119,P=0.036)and mRNA(t=4.051,P=0.015) levels of PTEN after 22 weeks of sodium arsenite treatment.Immunofluorescence results showed that after 4 weeks of sodium arsenite treatment,YTHDF2 LLPS droplets in YTHDF2-wt cells were localized to stress granules,translation-related membrane-less organelles.Conclusions During sodium arsenite-induced malignant transformation of skin cells,YTHDF2 undergoes LLPS and localizes to stress granules,translation-related membrane-less organelles.YTHDF2 LLPS participates in sodium arsenite-induced malignant transformation of skin cells by down-regulating the mRNA level of the key tumor suppressor PTEN.
Arsenites/toxicity* ; Sodium Compounds/toxicity* ; Humans ; Cell Transformation, Neoplastic/drug effects* ; PTEN Phosphohydrolase/metabolism* ; Cell Proliferation ; Skin/cytology* ; RNA-Binding Proteins ; Skin Neoplasms/chemically induced* ; Cell Line

Hypertrophic scar( HS) is a very common skin fibrosis disorder after human skin injury and wound healing. The objective of this study was to investigate the efficacy of cell penetrating peptide TAT-modified liposomes loaded with salvianolic acid B( SAB-TAT-LIP) on proliferation,migration and cell cycle of human skin fibroblasts( HSF),and preliminarily evaluate its effect on prevention and treatment of HS. HSF were cultured in vitro,and MTT assay was used to detect the inhibitory effect of SAB-TAT-LIP on cell proliferation. Cell migration was assessed by Transwell chamber method and scratch method; and cell cycle change was detected by flow cytometry. In vitro cell studies showed that blank liposome basically had no toxic effect on HSF. Different concentrations of SABTAT-LIP inhibited proliferation on HSF in varying degrees after intervention for different periods in a dose and time dependent manner;meanwhile,SAB-TAT-LIP significantly inhibited the migration and invasion of HSF. At the same time,SAB-TAT-LIP could block the cell cycle at G0/G1 phase after intervention for 48 h,P<0.01 as compared with the blank control group. Conclusively,our experimental data quantitatively demonstrate that SAB-TAT-LIP has significant inhibitory effect on cells proliferation,invasion and migration,with blocking effect on G0/G1 phase. This may offer a promising therapeutic strategy for transdermal delivery in prevention and treatment of HS.
Benzofurans ; pharmacology ; Cell Cycle ; Cell Movement ; Cell Proliferation ; Cell-Penetrating Peptides ; Cells, Cultured ; Drug Carriers ; Fibroblasts ; cytology ; drug effects ; Humans ; Liposomes ; Skin ; cytology

OBJECTIVESTo investigate the hair growth-promoting effect of Miscanthus sinensis var. purpurascens (MSP) flower extracton on in vitro and in vivo models.

METHODSMSP flower extract was extracted in 99.9% methanol and applied to examine the proliferation of human dermal papilla cells (hDPCs) in vitro at the dose of 3.92-62.50 μg/mL and hair growth of C57BL/6 mice in vivo at the dose of 1000 μg/mL. The expression of transforming growth factor β1 (TGF-β1), hepatocyte growth factor (HGF), β-catenin, substance P was measured by relative quantitative realtime polymerase chain reaction. Histopathological and immunohistochemical analysis were performed.

RESULTSMSP (7.81 μg/mL) down-regulated TGF-β1 and up-regulated HGF and β-catenin in hDPCs (P<0.01). MSP (1000 μg/mL)-treated mice showed the earlier transition of hair follicles from the telogen to the anagen phase. The number of mast cells was lower in the MSP-treated mice than in other groups (P<0.05 vs. NCS group). Substance P and TGF-β1 were expressed in hair follicles and skin of the MSP group lower than that in negative control. Stem cell factor in hair follicles was up-regulated in the MSP-treated mice (P<0.01).

CONCLUSIONSThe MSP flower extract may have hair growth-promotion activities.

Animals ; Antioxidants ; pharmacology ; Cell Count ; Cell Proliferation ; drug effects ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Female ; Flowers ; chemistry ; Hair Follicle ; cytology ; drug effects ; growth & development ; Hepatocyte Growth Factor ; metabolism ; Humans ; Mast Cells ; cytology ; Mice, Inbred C57BL ; Phosphorylation ; drug effects ; Plant Extracts ; pharmacology ; Poaceae ; chemistry ; RNA, Messenger ; genetics ; metabolism ; Skin ; metabolism ; Stem Cell Factor ; metabolism ; Stress, Psychological ; pathology ; Substance P ; metabolism ; Transforming Growth Factor beta ; genetics ; metabolism ; Vascular Endothelial Growth Factor A ; genetics ; metabolism ; beta Catenin ; metabolism

BACKGROUNDCathepsin L (CatL) is a cysteine protease with strong matrix degradation activity that contributes to photoaging. Mannose phosphate-independent sorting pathways mediate ultraviolet A (UVA)-induced alternate trafficking of CatL. Little is known about signaling pathways involved in the regulation of UVA-induced CatL expression and activity. This study aims to investigate whether a single UVA irradiation affects CatL expression and activity and whether mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) pathway is involved in the regulation of UVA-induced CatL expression and activity in human dermal fibroblasts (HDFs).

METHODSPrimary HDFs were exposed to UVA. Cell proliferation was determined by a cell counting kit. UVA-induced CatL production and activity were studied with quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), Western blotting, and fluorimetric assay in cell lysates collected on three consecutive days after irradiation. Time courses of UVA-activated JNK and p38MAPK signaling were examined by Western blotting. Effects of MAPK inhibitors and knockdown of Jun and Fos on UVA-induced CatL expression and activity were investigated by RT-PCR, Western blotting, and fluorimetric assay. Data were analyzed by one-way analysis of variance.

RESULTSUVA significantly increased CatL gene expression, protein abundance, and enzymatic activity for three consecutive days after irradiation (F = 83.11, 56.14, and 71.19, respectively; all P < 0.05). Further investigation demonstrated phosphorylation of JNK and p38MAPK activated by UVA. Importantly, inactivation of JNK pathway significantly decreased UVA-induced CatL expression and activity, which were not affected by p38MAPK inhibition. Moreover, knockdown of Jun and Fos significantly attenuated basal and UVA-induced CatL expression and activity.

CONCLUSIONSUVA enhances CatL production and activity in HDFs, probably by activating JNK and downstreaming AP-1. These findings provide a new possible molecular approach for antiphotoaging therapy.

Anthracenes ; pharmacology ; Cathepsin L ; metabolism ; Cells, Cultured ; Child ; Child, Preschool ; Enzyme Inhibitors ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; antagonists & inhibitors ; Fibroblasts ; cytology ; drug effects ; metabolism ; radiation effects ; Humans ; Imidazoles ; pharmacology ; MAP Kinase Signaling System ; drug effects ; radiation effects ; Oncogene Proteins v-fos ; genetics ; metabolism ; Proto-Oncogene Proteins c-jun ; genetics ; metabolism ; Pyridines ; pharmacology ; Skin ; cytology ; Ultraviolet Rays

PURPOSE: The purpose of this study was to evaluate the effects of essential oil on oxidative stress, immunity, and skin condition in atopic dermatitis (AD) induced mice. METHODS: This study was a 3x3 factorial design. Factors were oil type (Lavender, Thyme, and 2:1 mixture of lavender and thyme oil [blending oil]) and treatment period (0 day, 7 days, and 21 days). The samples were 45 mice with AD and randomly assigned to nine groups of five mice per group. The dependent variables such as superoxide radical, IgE, degranulated mast cells, and epidermal thickness were measured. Data were collected from February to April in 2014. Descriptive statistics, One-way ANOVA, Two-way ANOVA, and Tukey's HSD test were performed using the SPSS WIN 20.0 program. RESULTS: Dependent variables were not statistically significantly different by the three oil types (p >.05). Essential oils such as lavender, thyme, and blending oil were all effective in reducing AD symptoms and especially 2:1 blending oil were most effective. There were statistically significant differences by the three treatment periods in all dependent variables (p <.001). There were statistically significant interactions between oil types and treatment periods in all dependent variables (p <.01). For decreasing superoxide radical, degranulated mast cells, and epidermal thickness, 2:1 mixed oil should be applied for at least 21 days. Otherwise to reduce IgE, 2:1 mixed oil should be used for at least 7 days. CONCLUSION: These findings provide bases for developing effective interventions for AD patients to manage their AD symptoms.
Animals ; Dermatitis, Atopic/chemically induced/*drug therapy/pathology ; Disease Models, Animal ; *Immunity/drug effects ; Immunoglobulin E/blood ; Lavandula/*chemistry/metabolism ; Mast Cells/cytology/metabolism ; Mice ; Oils, Volatile/chemistry/pharmacology/therapeutic use ; *Oxidative Stress/drug effects ; Picryl Chloride/toxicity ; Plant Oils/chemistry/pharmacology/*therapeutic use ; Singlet Oxygen/metabolism ; Skin/drug effects/pathology ; Thymus Plant/*chemistry/metabolism

OBJECTIVETo explore the effects of different concentrations of putrescine on the proliferation, migration and apoptosis of human skin fibroblasts (HSF).

METHODSHSF cultured in the presence of 0.5, 1.0, 5.0, 10, 50, 100, 500, and 1000 µg/ putrescine for 24 h were examined for the changes in the cell proliferation, migration, and apoptosis using MTS assay, Transwell migration assay, and flow cytometry, respectively.

RESULTSCompared with the control cells, HSF cultured with 0.5, 1.0, 5.0, and 10 µg/ putrescine showed significantly increased cell proliferation (P<0.01), and the effect was the most obvious with 1 µg/ putrescine, whereas 500 and 1000 µg/ putrescine significantly reduced the cell proliferation (P<0.01); 50 and 100 µg/ did not obviously affect the cell proliferation (P>0.05). Putrescine at 1 µg/ most significantly enhanced the cell migration (P<0.01), while at higher doses (50, 100, 500, and 1000 µg/) putrescine significantly suppressed the cell migration (P<0.05); 0.5, 5.0, and 10 µg/ putrescine produced no obvious effects on the cell migration (P>0.05). HSF treated with 0.5, 1.0, 5.0, and 10 µg/ putrescine obvious lowered the cell apoptosis rate compared with the control group (P<0.01), and the cell apoptosis rate was the lowest in cells treated with 1 µg/ putrescine; but at the concentrations of 100, 500, and 1000 µg/, putrescine significantly increased the cell apoptosis rate (P<0.01), while 50 µg/ml putrescine produced no obvious effect on cell apoptosis (P>0.05).

CONCLUSIONLow concentrations of putrescine can obviously enhance the proliferation ability and maintain normal migration ability of HSF in vitro, but at high concentrations, putrescine can obviously inhibit the cell migration and proliferation and induce cells apoptosis, suggesting the different roles of different concentrations of putrescine in wound healing.

Apoptosis ; drug effects ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Fibroblasts ; cytology ; drug effects ; Flow Cytometry ; Humans ; Putrescine ; administration & dosage ; pharmacology ; Skin ; cytology ; Wound Healing

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 explore the effects of different concentrations of putrescine on proliferation, migration, and apoptosis of human umbilical vein endothelial cells (HUVECs).

METHODSHUVECs were routinely cultured in vitro. The 3rd to the 5th passage of HUVECs were used in the following experiments. (1) Cells were divided into 500, 1 000, and 5 000 µg/mL putrescine groups according to the random number table (the same grouping method was used for following grouping), with 3 wells in each group, which were respectively cultured with complete culture solution containing putrescine in the corresponding concentration for 24 h. Morphology of cells was observed by inverted optical microscope. (2) Cells were divided into 0.5, 1.0, 5.0, 10.0, 50.0, 100.0, 500.0, 1 000.0 µg/mL putrescine groups, and control group, with 4 wells in each group. Cells in the putrescine groups were respectively cultured with complete culture solution containing putrescine in the corresponding concentration for 24 h, and cells in control group were cultured with complete culture solution with no additional putrescine for 24 h. Cell proliferation activity (denoted as absorption value) was measured by colorimetry. (3) Cells were divided (with one well in each group) and cultured as in experiment (2), and the migration ability was detected by transwell migration assay. (4) Cells were divided (with one flask in each group) and cultured as in experiment (2), and the cell apoptosis rate was determined by flow cytometer. Data were processed with one-way analysis of variance, Kruskal-Wallis test, and Dunnett test.

RESULTS(1) After 24-h culture, cell attachment was good in 500 µg/mL putrescine group, and no obvious change in the shape was observed; cell attachment was less in 1 000 µg/mL putrescine group and the cells were small and rounded; cells in 5 000 µg/mL putrescine group were in fragmentation without attachment. (2) The absorption values of cells in 0.5, 1.0, 5.0, 10.0, 50.0, 100.0, 500.0, 1 000.0 µg/mL putrescine groups, and control group were respectively 0.588 ± 0.055, 0.857 ± 0.031, 0.707 ± 0.031, 0.662 ± 0.023, 0.450 ± 0.019, 0.415 ± 0.014, 0.359 ± 0.020, 0.204 ± 0.030, and 0.447 ± 0.021, with statistically significant differences among them (χ(2) = 6.86, P = 0.009). The cell proliferation activity in 0.5, 1.0, 5.0, and 10.0 µg/mL putrescine groups was higher than that in control group (P < 0.05 or P < 0.01). The cell proliferation activity in 500.0 and 1 000.0 µg/mL putrescine groups was lower than that in control group (with P values below 0.01). The cell proliferation activity in 50.0 and 100.0 µg/mL putrescine groups was close to that in control group (with P values above 0.05). (3) There were statistically significant differences in the numbers of migrated cells between the putrescine groups and control group (F = 138.662, P < 0.001). The number of migrated cells was more in 1.0, 5.0, and 10.0 µg/mL putrescine groups than in control group (with P value below 0.01). The number of migrated cells was less in 500.0 and 1 000.0 µg/mL putrescine groups than in control group (with P value below 0.01). The number of migrated cells in 0.5, 50.0, and 100.0 µg/mL putrescine groups was close to that in control group (with P values above 0.05). (4) There were statistically significant differences in the apoptosis rate between the putrescine groups and control group (χ(2)=3.971, P=0.046). The cell apoptosis rate was lower in 0.5, 1.0, 5.0, and 10.0 µg/mL putrescine groups than in control group (with P values below 0.05). The cell apoptosis rate was higher in 500.0 and 1 000.0 µg/mL putrescine groups than in control group (with P values below 0.01). The cell apoptosis rates in 50.0 and 100.0 µg/mL putrescine groups were close to the cell apoptosis rate in control group (with P values above 0.05).

CONCLUSIONSLow concentration of putrescine can remarkably enhance the ability of proliferation and migration of HUVECs, while a high concentration of putrescine can obviously inhibit HUVECs proliferation and migration, and it induces apoptosis.

Apoptosis ; drug effects ; Biological Products ; Cell Line ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Flow Cytometry ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; Humans ; Putrescine ; administration & dosage ; adverse effects ; pharmacology ; physiology ; Skin ; cytology ; Wound Healing

BACKGROUNDWe showed in our previous study that the N-terminal 17-mer peptide of amyloid precursor protein (APP17-mer peptide), an active peptide segment with trophic and antioxidative effects, protects skin fibroblasts against ultraviolet (UV) damage and downregulates matrix metalloproteinase 1 (MMP-1) expression. The aim of the current study was to explore the protective effects of P165, the N-terminal 5-mer peptide analog of amyloid precursor protein that is resistant to enzymolysis, on UVA-induced damage in human dermal fibroblasts (HDFs).

METHODSHDFs were cultured in Dulbecco's modified Eagle's medium without and with P165 (concentrations were 1, 10, and 100 µmol/L). Then, 15 J/cm(2) UVA irradiation was used to obtain the UV-irradiated model. Cell proliferation was analyzed using MTT kit. The collagen type I and MMP-1 contents in cell lysate were determined by enzyme-linked immunosorbent assay (ELISA). Fluorometric assays were performed to detect the formation of intracellular reactive oxygen species (ROS) in the cells.

RESULTSP165 significantly protected the HDFs against UVA-induced cytotoxicity. Compared with the UVA-irradiated control, 1, 10, and 100 µmol/L P165 elevated cell proliferation by 14.98% (P < 0.05), 17.52% (P < 0.01) and 28.34% (P < 0.001), respectively. Simultaneously, 10 and 100 µmol/L P165 increased collagen type I content (both P < 0.05). Moreover, P165 treatment (all concentrations) also markedly suppressed the UVA-induced MMP-1 expression (all P < 0.001). P165 at 1, 10, and 100 µmol/L also reduced UVA-induced ROS generation by 11.27%, 13.69% (both P < 0.05), and 25.48% (P < 0.001), respectively.

CONCLUSIONSP165 could protect the HDFs against UVA-induced photodamage, including cytotoxicity, and MMP-1 generation. Furthermore, it also increased the collagen type I content in the cells. The inhibitory effect on intracellular ROS generation might be involved in these photoprotective effects. Thus, P165 may be a useful candidate in the prevention and treatment of skin photoaging.

Amyloid beta-Protein Precursor ; pharmacology ; Cells, Cultured ; Fibroblasts ; drug effects ; radiation effects ; Humans ; Skin ; cytology ; Ultraviolet Rays