• Journal of Life Science
• /
• v.30 no.8
• /
• pp.688-694
• /
• 2020

In a previous study, the total phenolic content in ethanol extracts of medicinal plants that naturally grow on Jeju Island were analyzed with the extracts of Raphiolepsis indica leaf found to have the highest. The current study was carried out to evaluate the total flavonoid content, radical-scavenging activity, and the protective effect of R. indica extracts and solvent fractions on oxidative stress in HaCaT keratinocytes. More specifically, total flavonoid content and 2-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical-scavenging activity were measured to assess anti-oxidative activity, and protective effects against hydrogen peroxide (H₂O₂) were determined by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide assay on the HaCaT cells. Of the various fractions analyzed, the ethyl acetate extract of R. indica showed the highest total flavonoid content (149.13 mg/g extracts) and the lowest remaining ABTS. In addition, the ethyl acetate fraction was significantly more resistant against H₂O₂ than the negative control. Our results therefore suggest that an ethyl acetate fraction of R. indica protects HaCaT cells against oxidative stress and could prove useful for developing functional cosmetic materials.

• Proceedings of the SCSK Conference
• /
• 2003.09a
• /
• pp.780-803
• /
• 2003

Exposure of skin cells, particularly keratinocytes to various nuclear factor-kappaB ($\textrm{NF}_{-{\kappa}}\textrm{B}$) activators [e.g. tumor necrosis factor-$\alpha$, interleukin-1, lipopolysaccharides, and ultraviolet light] leads to phosphorylation and degradation of the inhibitory protein, $\textrm{I}_{{\kappa}}\textrm{B}$. Liberated $\textrm{NF}_{-{\kappa}}\textrm{B}$ is translocated into the nucleus where it can change or alter expression of target genes, resulting in the secretion of extracellular signaling molecules including melanotrophic factors affecting melanocyte. In order to demonstrate the possible role of $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation on the synthesis of melanotrophic factors from the keratinocytes, the activities of $\textrm{NF}_{-{\kappa}}\textrm{B}$ induced by melanogenic inhibitors (MIs) were determined in human HaCaT keratinocytes transfected with $\textrm{pNF}_{-{\kappa}}\textrm{B}$-SEAP-NPT plasmid. Transfectant cells released the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the $\textrm{NF}_{-{\kappa}}\textrm{B}$ activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selection marker for geneticin resistance. MIs such as niacinamide, kojic acid, hydroquinone, resorcinol, arbutin, and glycolic acid were preincubated with transfectant HaCaT cells for 3 h and then ultraviolet B (UVB) was irradiated. $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation was measured with the SEAP reporter gene assay using a fluorescence detection method. Of the Mis tested, kojic acid ($IC_{50}$/ = 60 $\mu$M) was found to be the most potent inhibitor of UVB-upregulating $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation in transfectant HaCaT cells, which is followed by niacinamide ($IC_{50}$/= 540 $\mu$M). Pretreatment of the transfectant HaCaT cells with the Mis, especially kojic acid and niacinamide, effectively lowered $\textrm{NF}_{-{\kappa}}\textrm{B}$ binding measured by electrophoretic mobility shift assay. Furthermore, these two inhibitors remarkably reduced the secretion level of IL-6, one of melanotrophic factors, triggered by UV-radiation of the HaCaT cells. These observations suggest that Mis working at the in vivo level might act partially through the modulation of the synthesis of melanotrophic factors in keratinocyte.

• The Korean Journal of Physiology and Pharmacology
• /
• v.23 no.2
• /
• pp.113-120
• /
• 2019

Mannosylerythritol lipids (MELs) are glycolipids and have several pharmacological efficacies. MELs also show skin-moisturizing efficacy through a yet-unknown underlying mechanism. Aquaporin-3 (AQP3) is a membrane protein that contributes to the water homeostasis of the epidermis, and decreased AQP3 expression following ultraviolet (UV)-irradiation of the skin is associated with reduced skin moisture. No previous study has examined whether the skin-moisturizing effect of MELs might act through the modulation of AQP3 expression. Here, we report for the first time that MELs ameliorate the UVA-induced downregulation of AQP3 in cultured human epidermal keratinocytes (HaCaT keratinocytes). Our results revealed that UVA irradiation decreases AQP3 expression at the protein and messenger RNA (mRNA) levels, but that MEL treatment significantly ameliorated these effects. Our mitogen-activated protein kinase inhibitor analysis revealed that phosphorylation of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38, mediates UVA-induced AQP3 downregulation, and that MEL treatment significantly suppressed the UVA-induced phosphorylation of JNK. To explore a possible mechanism, we tested whether MELs could regulate the expression of peroxidase proliferator-activated receptor gamma ($PPAR-{\gamma}$), which acts as a potent transcription factor for AQP3 expression. Interestingly, UVA irradiation significantly inhibited the mRNA expression of $PPAR-{\gamma}$ in HaCaT keratinocytes, whereas a JNK inhibitor and MELs significantly rescued this effect. Taken together, these findings suggest that MELs ameliorate UVA-induced AQP3 downregulation in HaCaT keratinocytes by suppressing JNK activation to block the decrease of $PPAR-{\gamma}$. Collectively, our findings suggest that MELs can be used as a potential ingredient that modulates AQP3 expression to improve skin moisturization following UVA irradiation-induced damage.

• Korean Journal of Pharmacognosy
• /
• v.43 no.3
• /
• pp.217-223
• /
• 2012

In the present study, we investigated anti-inflammatory activity of artemisinic acid in HaCaT cells and RAW264.7 cells. Artemisinic acid showed inhibitory activity on macrophage-derived chemokines (MDC) expression, a factor related with atopic dermatitis (AD), in interferon (IFN)-${\gamma}$ and tumor necrosis factor (TNF)-${\alpha}$-stimulated HaCaT cells. In the study on action mechanism, pretreated artemisinic acid reduced the phosphorylation of STAT1 and p38 and the degradation of $I{\kappa}B$ by IFN-${\gamma}$ and TNF-${\alpha}$ stimulations. However, artemisinic acid didn't show the inhibitory activity on LPS-induced inflammatory mediators (NO, $PGE_2$, IL-6) in RAW264.7 cell. These results indicate that artemisinic acid inhibits IFN-${\gamma}$ and TNF-${\alpha}$-induced MDC expression through inhibition of signal factors, STAT1, NF-${\kappa}B$, and p38, in HaCaT keratinocytes.

• Nutrition Research and Practice
• /
• v.16 no.1
• /
• pp.1-13
• /
• 2022

BACKGROUND/OBJECTIVES: Bitter taste receptors are taste signaling pathway mediators, and are also expressed and function in extra-gustatory organs. Skin aging affects the quality of life and may lead to medical issues. The purpose of this study was to better understand the anti-skin aging effects of bitter taste receptors in D-galactose (D-gal)-induced aged human keratinocytes, HaCaT cells. MATERIALS/METHODS: Expressions of bitter taste receptors in HaCaT cells and mouse skin tissues were examined by polymerase chain reaction assay. Bitter taste receptor was overexpressed in HaCaT cells, and D-gal was treated to induce aging. We examined the effects of bitter taste receptors on aging by using β-galactosidase assay, wound healing assay, and Western blot assay. RESULTS: TAS2R16 and TAS2R10 were expressed in HaCaT cells and were upregulated by D-gal treatment. TAS2R16 exerted protective effects against skin aging by regulating p53 and p21, antioxidant enzymes, the SIRT1/mechanistic target of rapamycin pathway, cell migration, and epithelial-mesenchymal transition markers. TAS2R10 was further examined to confirm a role of TAS2R16 in cellular senescence and wound healing in D-gal-induced aged HaCaT cells. CONCLUSIONS: Our results suggest a novel potential preventive role of these receptors on skin aging by regulating cellular senescence and wound healing in human keratinocyte, HaCaT.

• The Korea Journal of Herbology
• /
• v.34 no.2
• /
• pp.25-32
• /
• 2019

Objectives : Gardeniae Fructus extract is used as a component of various cosmetics. However, the effect of the extract on the motility of keratinocytes has not been studied. The aim of this study is to investigate the inhibitory effect of ethanol extract of Gardeniae Fructus (GFET) or ethyl acetate extract of Gardeniae Fructus (GFEA) on oxidation and motility of human keratinocyte HaCaT cells. Methods : Antioxidant activity of Gardeniae Fructus extracts were determined by the 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assay. To investigate the cytotoxicity of Gardeniae Fructus extracts, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay was performed. The mRNA expression levels of tight junction related genes were analyzed using quantitative RT-PCR analysis. Cell migration assay was employed to determine the activity of Gardeniae Fructus extracts on motility of human keratinocyte HaCaT cells. Results : GFET and GFEA showed strong antioxidant activity. GFEA showed stronger cytotoxicity in HaCaT cells than GFET until $2.0mg/m{\ell}$ concentration. Cell migration assay demonstrated that GFET and GFEA decreased the motility of HaCaT cells. In addition, the mRNA expression level of claudin 8 among tight junction genes was significantly reduced by GFET or GFEA treatment. Conclusions : We investigated the physiological activities of the extracts of Gardeniae Fructus extracts on human keratinocytes by two different extraction methods. In addition, the mRNA expression level of claudin 8 among tight junction genes was significantly reduced by either GFET or GFEA treatment. This study provides basic information on the application of Gardeniae Fructus extract to cosmetics component.

• The Journal of Korean Medicine
• /
• v.44 no.2
• /
• pp.119-131
• /
• 2023

Objectives: Betula Platyphylla(BP) has been used as a analgesic, anti-microbial, anti-oxidant drug in Eastern Asia. However, it is still unknown whether BP ethanol extract could exhibit the inhibitory activities against ultraviolet B(UVB)-induced skin injury on human keratinocytes, HaCaT cells. This study was aimed to investigate the protective activity of BP ethanol extract on UVB-irradiated skin injury in HaCaT cells. Methods: The skin injury model of HaCaT cells was established under UVB stimulation. HaCaT keratinocyte cells were pre-treated with BP ethanol extract for 1 h, and then stimulated with UVB. Then, the cells were harvested to measure the cell viability, production of reactive oxygen species(ROS), pro-inflammatory cytokines such as interleukin(IL) 1-beta, IL-6, and tumor necrosis factor(TNF)-𝛼, hyaluronidase, type 1 collagen, matrix metalloproteinase(MMP)s. In addition, we examined the mitogen activated protein kinases(MAPKs) and inhibitory kappa B alpha(I𝜅;-B𝛼) as inhibitory mechanisms of BP ethanol extract. Results: The treatment of BP ethanol extract inhibited the UVBinduced cell death and ROS production in HaCaT cells. BP ethanol extract treatment inhibited the UVB-induced increase of IL-1beta, IL-6, and TNF-𝛼. BP ethanol extract treatment inhibited the increase of hyaluronidase, MMP and decrease of collagen. BP ethanol extract treatment inhibited the activation of MAPKs and the degradation of I𝜅-B𝛼. Conclusions: Our result suggest that treatment of BP ethanol extract could inhibit the UVB-induced skin injury via deactivation of MAPKs and nuclear factor kappa B(NF-𝜅B) in HaCaT cells. This study could suggest that BP ethanol extract could be a beneficial agent to prevent skin damage or inflammation.

• Microbiology and Biotechnology Letters
• /
• v.49 no.4
• /
• pp.528-533
• /
• 2021

The microalga, Tetrathelmis tetrathele, is used in the development of products for the aquaculture, food, and nutraceutical industries. In the present study, we investigated whether the T. tetrathele ethanolic extract (TTE), which has anti-inflammatory properties, can confer protection against alopecia and improve scalp health, influence the proliferation of human keratinocytes, HaCaT cells, and human hair follicle dermal papilla cells (HFDPC), or inhibit 5α-reductase activity. We found that TTE inhibited the production of the inflammatory mediator, nitric oxide (NO), and prostaglandin E₂ (PGE₂) without cytotoxicity in LPS-stimulated RAW 264.7 cells. In addition, TTE encouraged the proliferation of HaCaT cells and HFDPC. Our results showed that TTE had anti-inflammatory activities, proliferated HaCaT cells and HFDPC, and inhibited 5α-reductase activity. Therefore, we suggest that T. tetrathele could be a potent therapeutic agent for alopecia prevention and scalp improvement.

• Toxicological Research
• /
• v.18 no.3
• /
• pp.227-232
• /
• 2002

In order to find out the appropriate in vitro method for high correlation with in vivo, we com-pared the sensitivities of phototoxicity (PT) in vitro method between in human keratinocytes, HaCaT cells and in 3T3 fibroblast cells derived from Balb/c mice. Both cells were exposed to six known phototoxic chemicals : promethazine, neutral red, chlortetracycline, amiodarone, bithionol, 8-methoxypsoralen, or non-phototoxic chemical, ALS (ammonium laureth sulfate) and then irradiated with 5 J/$cm^2$ of UVA. Cell viability ($IC_{50}$ ) was measured by neutral red uptake (NRU) assay. The ratio of $IC_{50}$ value of chemicals in the presence and absence of UVA was determined by the cut-off value. The phototoxic potential of test chemicals in NRU assay was determined by measuring the photoirriation factor (PIF) with a cut-off value of 5. In both 3T3 and HaCaT cells, all known phototoxic chemicals were positive (over 5 of PIF value), except that bithionol was found to be non-phototoxic to HaCaT cells, and ALS, non-phototoxic chemical was negative. These results suggest that Balb/c 3T3 cell was more sensitive than HaCaT cell to predict phototoxicity potential.

• Biomolecules & Therapeutics
• /
• v.24 no.5
• /
• pp.529-535
• /
• 2016

Atopic dermatitis (AD) results from gene and environment interactions that lead to a range of immunological abnormalities and breakdown of the skin barrier. Protease-activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is expressed in suprabasal layers of the epidermis. PAR2 is activated by both trypsin and a specific agonist peptide, SLIGKV-$NH_2$ and is involved in both epidermal permeability barrier homeostasis and epithelial inflammation. In this study, we investigated the effect of lobaric acid on inflammation, keratinocyte differentiation, and recovery of the skin barrier in hairless mice. Lobaric acid blocked trypsin-induced and SLIGKV-$NH_2$-induced PAR2 activation resulting in decreased mobilization of intracellular $Ca^{2+}$ in HaCaT keratinocytes. Lobaric acid reduced expression of interleukin-8 induced by SLIGKV-$NH_2$ and thymus and activation regulated chemokine (TARC) induced by tumor necrosis factor-a (TNF-${\alpha}$) and IFN-${\gamma}$ in HaCaT keratinocytes. Lobaric acid also blocked SLIGKV-$NH_2$-induced activation of ERK, which is a downstream signal of PAR2 in normal human keratinocytes (NHEKs). Treatment with SLIGKV-$NH_2$ downregulated expression of involucrin, a differentiation marker protein in HaCaT keratinocytes, and upregulated expression of involucrin, transglutamase1 and filaggrin in NHEKs. However, lobaric acid antagonized the effect of SLIGKV-$NH_2$ in HaCaT keratinocytes and NHEKs. Topical application of lobaric acid accelerated barrier recovery kinetics in a SKH-1 hairless mouse model. These results suggested that lobaric acid is a PAR2 antagonist and could be a possible therapeutic agent for atopic dermatitis.