• Biomolecules & Therapeutics
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• v.23 no.4
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• pp.357-366
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• 2015

Isorhamnetin (3-methylquercetin) is a flavonoid derived from the fruits of certain medicinal plants. This study investigated the photoprotective properties of isorhamnetin against cell damage and apoptosis resulting from excessive ultraviolet (UV) B exposure in human HaCaT keratinocytes. Isorhamnetin eliminated UVB-induced intracellular reactive oxygen species (ROS) and attenuated the oxidative modification of DNA, lipids, and proteins in response to UVB radiation. Moreover, isorhamnetin repressed UVB-facilitated programmed cell death in the keratinocytes, as evidenced by a reduction in apoptotic body formation, and nuclear fragmentation. Additionally, isorhamnetin suppressed the ability of UVB light to trigger mitochondrial dysfunction. Taken together, these results indicate that isorhamnetin has the potential to protect human keratinocytes against UVB-induced cell damage and death.

• Nutrition Research and Practice
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• v.11 no.4
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• pp.275-280
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• 2017

BACKGROUND/OBJECTIVES: Re-epithelialization has an important role in skin wound healing. Astaxanthin (ASX), a carotenoid found in crustaceans including shrimp, crab, and salmon, has been widely used for skin protection. Therefore, we investigated the effects of ASX on proliferation and migration of human skin keratinocyte cells and explored the mechanism associated with that migration. MATERIAL/METHOD: HaCaT keratinocyte cells were exposed to $0.25-1{\mu}g/mL$ of ASX. Proliferation of keratinocytes was analyzed by using MTT assays and flow cytometry. Keratinocyte migration was determined by using a scratch wound-healing assay. A mechanism for regulation of migration was explored via immunocytochemistry and western blot analysis. RESULTS: Our results suggest that ASX produces no significant toxicity in human keratinocyte cells. Cell-cycle analysis on ASX-treated keratinocytes demonstrated a significant increase in keratinocyte cell proliferation at the S phase. In addition, ASX increased keratinocyte motility across the wound space in a time-dependent manner. The mechanism by which ASX increased keratinocyte migration was associated with induction of filopodia and formation of lamellipodia, as well as with increased Cdc42 and Rac1 activation and decreased RhoA activation. CONCLUSIONS: ASX stimulates the migration of keratinocytes through Cdc42, Rac1 activation and RhoA inhibition. ASX has a positive role in the re-epithelialization of wounds. Our results may encourage further in vivo and clinical study into the development of ASX as a potential agent for wound repair.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.1
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• pp.9-20
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• 2015

Ultraviolet radiation (UV) is a major cause of skin photoaging, and effective UV protecting agents are needed for the skin health and beauty. This study was undertaken to examine the effects of Bambusae caulis in Taeniam extract (BCTE) on UVB-induced cell death, oxidative stress and matrix metalloproteinase 1 (MMP1) expression in cell-based assays. HaCaT human keratinocytes were exposed to UVB in the presence of BCTE at different concentrations and resulting changes in cell viability and biochemical events were determined. The results showed that BCTE enhanced the viabilities of UVB-exposed cells, and attenuated apoptotic events such as cleavage of procaspase 3 to its active form, and the increase of Bax to Bcl-2 ratios. BCTE also attenuated the reactive oxygen generation and lipid peroxidation in cells exposed to UVB. Additionally, it attenuated the expression of matrix metalloproteinase 1 and the phosphorylation of c-Jun N-terminal kinase stimulated by UVB. Conclusively, the present study demonstrated that BCTE pro tected skin cells from the UVB-induced cell death, oxidative stress and MMP1 expression, suggesting its potential use as a cosmetic ingredient mitigating some features of the skin photoaging.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.1989-1996
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• 2015

Ice-binding proteins (IBPs) can inhibit ice recrystallization (IR), a major cause of cell death during cryopreservation. IBPs are hypothesized to improve cell viability after cryopreservation by alleviating the cryoinjury caused by IR. In our previous studies, we showed that supplementation of the freezing medium with the recombinant IBP of the Arctic yeast Glaciozyma sp. (designated as LeIBP) could reduce post-thaw hemolysis of human red blood cells and increase the survival of cryopreserved diatoms. Here, we showed that LeIBP could improve the viability of cryopreserved mammalian cells. Human cervical cancer cells (HeLa), mouse fibroblasts (NIH/3T3), human preosteoblasts (MC3T3-E1), Chinese hamster ovary cells (CHO-K1), and human keratinocytes (HaCaT) were evaluated. These mammalian cells were frozen in dimethyl sulfoxide (DMSO)/fetal bovine serum (FBS) solution with or without 0.1 mg/ml LeIBP at a cooling rate of -1℃/min in a -80℃ freezer overnight. The minimum effective concentration (0.1 mg/ml) of LeIBP was determined, based on the viability of HeLa cells after treatment with LeIBP during cryopreservation and the IR inhibition assay results. The post-thaw viability of mammalian cells was examined. In all cases, cell viability was significantly enhanced by more than 10% by LeIBP supplementation in 5% DMSO/5% FBS: viability increased by 20% for HeLa cells, 28% for NIH/3T3 cells, 21% for MC3T3-E1, 10% for CHO-K1, and 20% for HaCaT. Furthermore, addition of LeIBP reduced the concentrations of toxic DMSO and FBS down to 5%. Therefore, we demonstrated that LeIBP can increase the viability of cryopreserved mammalian cells by inhibiting IR.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1314-1319
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• 2009

In previous study, we have shown that continentalic acid (CA) isolated from Aralia continentalis induced the growth inhibition and apoptosis in HepG2 cells. In this study, we examine the effects of CA from A. continentalis on growth inhibition and apoptosis induction in human leukemia HL-60 and mouse fibroblast NIH 3T3 cell lines. The results demonstrated that CA decreased cell growth of leukemia HL-60 cells but not human HaCaT keratinocytes, assessed with the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] and LDH (lactate dehydrogenase) assay. Flow cytometric analysis of mouse fibroblast cell lines exposed to CA showed that apoptotic cells increased in a time- and dose-dependent manner. Treatment with CA decreased the number of normal cells and increased the number of early apoptotic and late apoptotic cells in a dose-dependent manner. The induction of apoptosis in mouse cell lines by CA was mediated through the activation of caspase-3, Bak, and Bax and the down-regulation of Bcl-2. Our results suggest that CA efficiently induces apoptosis in human leukemia cells.

• Biomedical Science Letters
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• v.17 no.1
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• pp.55-60
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• 2011

Skin is a physical barrier against diverse injury and damages. Exposure to ultraviolet (UV) radiation causes detrimental skin injuries such as inflammation and cell death. The value of natural pigments could be applied to many usages including cosmetics. This study was conducted to examine the protective effect of natural pigments extracted from mulberry, balsam pear, purple-colored sweet potato, pehmannia root, gardenia fruit, and black rice against UV-induced cell death in HaCaT cells, human keratinocyte cell lines. In the present study, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr induced cell death in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In addition, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr also increased lipid peroxide (LPO) formation, compared to control in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In conclusion, the extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice prevented the UV-B-induced cell apoptosis via the inhibition of oxidative stress in HaCaT cells.

• BMB Reports
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• v.50 no.11
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• pp.584-589
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• 2017

Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-${\alpha}$, contributes to the entry of immune cells into the site of inflammation in the skin. Here, we show that protein tyrosine phosphatase non-receptor type 21 (PTPN21) negatively regulates ICAM-1 expression in human keratinocytes. PTPN21 expression was transiently induced after stimulation with TNF-${\alpha}$. When overexpressed, PTPN21 inhibited the expression of ICAM-1 in HaCaT cells but PTPN21 C1108S, a phosphatase activity-inactive mutant, failed to inhibit ICAM-1 expression. Nuclear factor-${\kappa}B$ (NF-${\kappa}B$), a key transcription factor of ICAM-1 gene expression, was inhibited by PTPN21, but not by PTPN21 C1108S. PTPN21 directly dephosphorylated phospho-inhibitor of ${\kappa}B$ ($I{\kappa}B$)-kinase ${\beta}$ ($IKK{\beta}$) at Ser177/181. This dephosphorylation led to the stabilization of $I{\kappa}B{\alpha}$ and inhibition of NF-${\kappa}B$ activity. Taken together, our results suggest that PTPN21 could be a valuable molecular target for regulation of inflammation in the skin by dephosphorylating p-$IKK{\beta}$ and inhibiting NF-${\kappa}B$ signaling.

• Natural Product Sciences
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• v.18 no.1
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• pp.52-59
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• 2012

In our continuous efforts to procure the active materials from natural products in the protective effects of oxidative stress or UV damage to skin cells we found the Prunus persica flesh extract (PPFE) is considerable to meet the demand to protect the skin damage. PPFE attenuated cell damage induced by hypoxanthine-xanthine oxidase in cultured human keratinocytes, indicating that PPFE has the potential of the scavenging effect of reactive oxygen species (ROS) in human skin cell. Moreover, PPFE significantly suppressed UVA-induced ROS production determined by the oxidation of 2,7-dichlorodihydrofluorescein diacetate (DCFH) using FACS analysis. Additional study revealed that UVA irradiation of HaCaT human keratinocytes increased the gelatinolytic activities of matrix metalloproteinase-2, and -9 (MMP-2, -9) and mRNA expression of MMP-9 analyzing by a real-time reverse transcriptase-polymerase chain reaction (RT-PCR), and these events were significantly suppressed by the treatment with PPFE. These results suggest that PPFE might be applicable as natural ingredients for skin antiaging agents via UV-induced ROS scavenging activity and suppression of MMP expression in the skin cells.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.788-794
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• 2016

Vinca alkaloids from plant Vinca minor have been investigated for their effects of tyrosinase inhibition, stimulation of ROS generation and increasement of cell migration activity. The methanolic crude extract and the water-soluble fraction exhibited $IC_{50}$ value of 3.1 mg/mL and 2.1 mg/mL. Vinca minor extract treatment significantly increased ROS levels in HaCaT cells, in a concentration-dependent manner. Treatments of Vinca minor extract led to increase wound closure when compared with non-treatment. Low dose (0.1% or 0.3%) of extracts have not significantly affected, compared with that in controls. By contrast, 0.5% extract have dramatic effect on wound healing activity of keratinocytes. Effects of Vinca minor extract in a filter-based cell mobility assay appear similar to that of wound closure assay, which suggests that the Vinca minor extract have wound healing effects on skin.

• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.95-101
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• 2020

Psoriasis is an autoimmune skin disease that is accompanied by hyper proliferation of the epidermis, erythema of various sizes, and ulceration. However, the mechanism of the development of psoriasis dermatitis is unclear. Recently, it is known that the inflammatory cytokines and Th17 cells as well as chemokine (CC motif) ligand 20 (CCL20) are involved in the process of keratinocytes hyper-differentiation, which is common in psoriasis dermatitis. Therefore, we studied the effects of yakuchinone-A, an active ingredient of Alpinia oxyphylla Miquel known for its anti-inflammatory activity, to improve psoriasis dermatitis. First, cytotoxicity of yakuchinone-A was observed in cell counting kit-8 assay and not observed in 10 ㎍/mL concentration on the human keratinocyte HaCaT cells. Yakuchinone-A in the presence of tumor necrosis factor-alpha (TNF-α) on HaCaT cells inhibited mRNA expression of IL-6, IL-8, and TNF-α by up to 61.4±7.5, 23.6±1.5, 46.0±4.8%. CCL20, a chemokine that attracts immune cells such Th17 cells to the inflammation location, was also significantly suppressed by yakuchinone-A. In addition, IκB and STAT3 phosphorylation involved in the CCL20 expression was inhibited by yakuchinone-A in a concentration-dependent manner up to the level of 79.1±5.0, 80.8±2.3%. Furthermore, yakuchinone-A downregulated CCL20 mRNA expression level on IL-17A-activated HaCaT cells as a concentration-dependent manner. Based on these results, yakuchinone-A is expected to be developed as a new material for improving psoriasis dermatitis in the future.