Oxidative Stress In Human Keratinocytes Research Articles

Anti-aging Potential of Extracts Prepared from Fruits and Medicinal Herbs Cultivated in the Gyeongnam Area of Korea.

Many recent studies have focused on maintaining a healthy life by preventing and/or postponing the aging process. Numerous studies have reported that continuous exposure to reactive oxygen species can stimulate skin aging and that excessive accumulation of fat can cause an impaired skin barrier and tissue structure alterations. Thus, the maintenance of antioxidant homeostasis and the suppression of adipose accumulation are important strategies for skin anti-aging. Here, we prepared three types of extracts [whole juice, acetone-perchloric acid (PCA), and ethanol] from 20 fruits and medicinal herbs native to the Gyeongnam area of Korea. The total phenolic content of each extract was analyzed, and we observed higher total phenolic contents in the medicinal herbs. Consistent with this, the results of the oxygen radical absorbance activity capacity assay indicated that the in vitro antioxidant activities of the medicinal herb extracts were stronger than those of the fruit extracts. The fruits and medicinal herbs had strong effects on cell-based systems, including H2O2-induced oxidative stress in human keratinocytes and 3T3-L1 lipid accumulation. Nishimura Wase persimmon, Taishu persimmon, wrinkled giant hyssop, sweet wormwood, Chinese cedar, red perilla, tan shen, hiyodori-jogo, and cramp bark may be natural anti-aging materials with effective antioxidant and anti-adipogenic activities. Taken together, our findings may provide scientific evidence supporting the development of functional foods and nutraceuticals from fruits and medicinal herbs.

Oridonin protects HaCaT keratinocytes against hydrogen peroxide-induced oxidative stress by altering microRNA expression

microRNAs (miRNAs) have been shown to function as primary regulators of a variety of biological processes, including proliferation, differentiation and apoptosis in human keratinocytes. However, the biological significance of miRNAs in the defense against oxidative stress in keratinocytes remains to be elucidated. In this study, we demonstrate that oridonin, a diterpenoid compound isolated from Rabdosia rubescens with established antioxidant properties, protects HaCaT human keratinocytes from oxidative stress induced by exposure to hydrogen peroxide (H2O2). Our data demonstrate that low doses of oridonin (1-5 µM) protect keratinocytes against H2O2-induced apoptosis in a concentration- and time-dependent manner. Moreover, as shown by our results, oridonin markedly decreased H2O2-induced reactive oxygen species production in HaCaT cells. Oridonin mediated these effects by altering miRNA expression. Bioinformatics analysis identified several putative target genes of the differentially expressed miRNAs. Assessment of their gene ontology annotation revealed that these target genes are likely involved in cell growth and inhibition of apoptosis. Thus, the data from this study establish a role for miRNAs in mediating oridonin-induced protective effects against oxidative stress in human keratinocytes.

Hydrogen peroxide로 산화적 스트레스가 유도된 HaCaT keratinocyte에서 금은화의 세포 보호 효과

Objectives : Lonicerae Japonicae Flos (LJF) has been shown anti-oxidant, anti-inflammatory, anti-viral, anti-rheumatoid properties. However, it is still largely unknown whether LJF inhibits skin injury against oxidative stress in human keratin ocyte, HaCaT cells. The purpose of this study was to evaluate the protective effects of LJF against hydrogen peroxide(H2O2)-induced oxidative stress in human keratinocytes, HaCaT cells. Methods : To evaluate out the protective effects of LJF on oxidative inju ry in HaCaT cells, an oxidative stress model of HaCaT cells was established under a suitable concentration (500 µM) hydrogen peroxide. HaCaT keratinocyte cells were pre-treated with LJF (0.1, 0.25 or 0.5 mg/ml), and then stimulated with H2O2. Then, the cells were harvested to measure the cell viability, DNA damage, and release of reactive oxygen species (ROS). Results : LJF (0.1, 0.25 or 0.5 mg/ml) itself did not show any significant toxicity in HaCaT cells. The treatment of H2O2 caused the oxidative stress, leading to the cell death, and DNA injury. However, pretreatment with LJF reduced cell death, and DNA injury. The stimulation of H2O2 on HaCaT cells resulted in excessive release of ROS, which is the main factor of oxidative stress. The excessive release of ROS was inhibited by LJF treatment significantly. Conclusions : These results could suggest that LJF exhibited the protective effects of HaCaT cells against H2O2 -induced oxidative stress by inhibiting ROS release. It could be explained that LJF inhibit skin damages against oxidative stress. Thus, LJF would be useful for the dev elopment of drug or cosmetics treating skin troubles.

Influence of non-thermal atmospheric pressure plasma on cellular structures and processes in human keratinocytes (HaCaT)

BackgroundThe use of non-thermal atmospheric pressure plasma in dermatology to improve the healing of chronic wounds is a promising application. The antimicrobial properties of physical plasma offer on the one hand the killing of bacteria, which are often a problem in chronic wounds. On the other hand, plasma can activate cells which are involved in the wound closure. ObjectiveTo guarantee a safe application it is essential to understand basic interactions between physical plasma and human skin cells. MethodsIn our study, human keratinocytes (HaCaT cells) were directly plasma treated with a dielectric barrier discharge (DBD) plasma source and effects on viability, DNA, cell cycle, intracellular concentration of reactive oxygen species and induction of apoptosis were observed. ResultsA treatment time-dependent loss of recovered adherent HaCaT cells after 24h and a linear increase of DNA damage were observed, which was no longer evident 24h after plasma stimulation, except for long treatment times. An accumulation of HaCaT cells in G2/M phase and a decrease in the G1 phase was caused by DBD plasma. The increasing formation of intracellular ROS is also attributed to plasma treatment. In contrast to other studies we did not find clear evidences for apoptosis in adherent HaCaT cells. A culture medium exchange subsequently after plasma treatment weakened the observed effects. ConclusionDBD plasma treatment resulted in oxidative stress in human keratinocytes which is related to deficient cell performance.

Comparison of Biological Effects on Human Keratinocytes Using Different Plasma Treatment Regimes

This study investigated the influence of the plasma treatment regime on human keratinocytes (HaCaT cells). HaCaT cells were plasma treated with a volume dielectric barrier discharge plasma source in three different ways: directly, directly with culture medium exchange, and indirectly (in which only cell culture medium was exposed to plasma). The influence of dielectric barrier discharge plasma on viability, DNA, cell cycle, and intracellular concentration of reactive oxygen species in HaCaT cells was investigated. Direct and indirect plasma treatment caused a treatment time–dependent decrease of viable cells. An increase in DNA damage was observed immediately after plasma treatment, which was diminished after 24 h. Intracellular reactive oxygen species increased with longer plasma treatment times. The cell cycle analysis showed an accumulation of cells in the G2/M phase at the expense of cells in the G1 phase. An immediate exchange of culture medium after plasma treatment attenuated the described effects. Direct and indirect plasma treatment of adherent HaCaT cells resulted in comparable effects that depend on the plasma treatment time. Physical plasma seems to generate long-living reactive species or to modify organic components of the cell culture medium. Both mechanisms can initiate oxidative stress in human keratinocytes, which is responsible for the observed effects.

Photo-protection by 3-bromo-4, 5-dihydroxybenzaldehyde against ultraviolet B-induced oxidative stress in human keratinocytes

Exposure of the skin to ultraviolet B (UVB) radiation leads to epidermal damage and the generation of reactive oxygen species (ROS) in skin cells, including keratinocytes. Therefore, the photo-protective effect of 3-bromo-4, 5-dihydroxybenzaldehyde (BDB) against UVB was assessed in human HaCaT keratinocytes exposed to UVB radiation in vitro. BDB restored cell viability, which decreased upon exposure to UVB radiation. BDB exhibited scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl radicals, intracellular ROS induced by hydrogen peroxide (H2O2) or UVB radiation, the superoxide anion generated by the xanthine/xanthine oxidase system, and the hydroxyl radical generated by the Fenton reaction (FeSO4+H2O2). Moreover, BDB absorbed UVB and decreased injury resulting from UVB-induced oxidative stress to lipids, proteins and DNA. Finally, BDB reduced UVB-induced apoptosis, as exemplified by fewer apoptotic bodies and a reduction in DNA fragmentation.Taken together, these results suggest that BDB protects human keratinocytes against UVB-induced oxidative stress by scavenging ROS and absorbing UVB rays, thereby reducing injury to cellular components.

Inhibition of Matrix Metalloproteinase-1 Induced by Oxidative Stress in Human Keratinocytes by Mangiferin Isolated fromAnemarrhena asphodeloides

Oxidative stress is related to the synthesis of matrix metalloproteinases (MMPs), which cause skin aging. The protective effects of mangiferin derived from Anemarrhena asphodeloides were investigated against hydrogen peroxide (H(2)O(2))-induced damage using human skin keratinocyte (HaCaT) cells. Mangiferin was found to scavenge intracellular reactive oxygen species (ROS), superoxide radicals, and hydroxyl radicals. ROS regulate MMPs gene expression and activation of proenzymes. Mangiferin inhibited H(2)O(2)-induced MMP-1 gene expression and protein levels as well as its activity. Moreover, it abrogated mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) pathway and stress-activated protein kinase/extracellular signal-regulated kinase (SEK)-c-JUN N-terminal kinase (JNK) pathway, which are induced by H(2)O(2) treatment. And, it inhibited DNA binding activity of activator protein-1 (AP-1), a transcription factor of MMP-1 and downstream of ERK and JNK. Finally, it protected the human skin keratinocytes from H(2)O(2)-induced cell death. Taken together, these results indicate that mangiferin attenuated H(2)O(2)-induced MMP-1 activation via inhibition of ERK and JNK pathway and AP-1.

Inhibitory Effects of Triphlorethol-A on MMP-1 Induced by Oxidative Stress in Human Keratinocytes via ERK and AP-1 Inhibition

Oxidative stress is known to generate reactive oxygen species (ROS) in cells, which subsequently induce the synthesis of matrix metalloproteinases (MMP) and an aging phenomenon. The protective effects of triphlorethol-A, derived from Ecklonia cava, were investigated against hydrogen peroxide (H2O2)-induced damage using human skin keratinocytes. Data showed that triphlorethol-A inhibited ROS formation, induced catalase expression, inhibited DNA damage, and increased cell viability in keratinocytes. Triphlorethol-A treatment significantly reduced MMP-1 expression and production, compared to H2O2-treated cells. In addition, triphlorethol-A abrogated the activation of extracellular signal regulated protein kinase (ERK), which originates upstream of MMP-1 expression, and was induced by H2O2 treatment. Moreover, triphlorethol-A inhibited DNA binding activity of activator protein-1 (AP-1), a downstream transcription factor of ERK. Data indicate that the antioxidative properties of triphlorethol-A involve the inhibition of MMP-1 via ERK and AP-1 inhibition.

UVB induced oxidative stress in human keratinocytes and protective effect of antioxidant agents

This study aims at exploring the oxidative stress in keratinocytes induced by UVB irradiation and the protective effect of nutritional antioxidants. Cultured Colo-16 cells were exposed to UVB in vitro followed by measurement of reactive oxygen species (ROS), endogenous antioxidant enzyme activity, as well as cell death in the presence or absence of supplementation with vitamin C, vitamin E, or Ginsenoside Panoxatriol. Intracellular ROS content was found significantly reduced 1 h after exposure, but increased at later time points. After exposure to 150-600 J m(-2) UVB, reduction of ROS content was accompanied by increased activity of catalase and CuZn-superoxide dismutase at early time points. Vitamins C and E, and Ginsenoside Panoxatriol counteracted the increase of ROS in the Colo-16 cells induced by acute UVB irradiation. At the same time, Ginsenoside Panoxatriol protected the activity of CuZn-superoxide dismutase, while vitamin E showed only a moderate protective role. Vitamins C and E, and Ginsenoside Panoxatriol in combination protected the Colo-16 cells from UVB-induced apoptosis, but not necrosis. These findings suggest that vitamins C and E as well as Ginsenoside Panoxatriol are promising protective agents against UVB-induced damage in skin cells.

Influence of silymarin and its flavonolignans on H 2O 2-induced oxidative stress in human keratinocytes and mouse fibroblasts

The administration of antioxidants has been shown to enhance repair and healing processes in cutaneous tissue. Silymarin, an extract from Silybum marianum has been reported to be beneficial in the treatment of chemically-induced oxidative stress in mouse. In this study, we investigated the protective effects of silymarin, its flavonolignans silybin and dehydrosilybin and flavonoids quercetin and taxifolin against hydrogen peroxide-induced damage to human keratinocytes and mouse fibroblasts. The results showed that the cytotoxicity of hydrogen peroxide was dose-dependent in both cell lines. Pre-treatment with test compounds decreased oxidative injury. Dehydrosilybin and quercetin were the most powerful protectants. Silymarin was comparable to silybinin, its main component. This correlates with the antioxidant potential of the compounds. Our findings suggest that silymarin, flavonolignans and flavonoids may be useful as agents for improving skin tissue regeneration.

Protective Effects of Cyanidin‐3‐O‐β‐glucopyranoside Against UVA‐induced Oxidative Stress in Human Keratinocytes¶

ABSTRACTUltraviolet‐A (UVA) radiation causes significant oxidative stress because it leads to the generation of reactive oxygen species (ROS), leading to extensive cellular damage and eventual cell death either by apoptosis or necrosis. We evaluated the protective effects of cyanidin‐3‐O‐β‐glucopyranoside (C‐3‐G) against UVA‐induced apoptosis and DNA fragmentation in a human keratinocyte cell line (HaCaT). Treatment of HaCaT cells with C‐3‐G before UVA irradiation inhibited the formation of apoptotic cells (61%) and DNA fragmentation (54%). We also investigated antioxidant properties of C‐3‐G in HaCaT cells against ROS formation at apoptotic doses of UVA; C‐3‐G inhibited hydrogen peroxide (H2O2) release (an indicator of cellular ROS formation) after UVA irradiation. Further confirmation of the potential of C‐3‐G to counteract UVA‐induced ROS formation comes from our demonstration of its ability to enhance the resistance of HaCaT cells to the apoptotic effects of both H2O2 and the superoxide anion (O2•−), two ROS involved in UVA‐oxidative stress. Furthermore, in terms of Trolox Equivalent Antioxidant Activity, C‐3‐G treatment led to a greater increase in antioxidant activity in the membrane‐enriched fraction than in the cytosol (55%vs 19%). The protective effects against UVA‐induced ROS formation can be attributed to the higher membrane levels of C‐3‐G incorporation. These encouraging in vitro results support further research into C‐3‐G (and other anthocyanins) as novel agents for skin photoprotection.

Protective effects of Cyanidin-3-O-β-glucopyranoside against UVA-Induced Oxidative Stress in Human Keratinocytes

Ultraviolet-A (UVA) radiation causes significant oxidative stress because it leads to the generation of reactive oxygen species (ROS), leading to extensive cellular damage and eventual cell death either by apoptosis or necrosis. We evaluated the protective effects of cyanidin-3-O-beta-glucopyranoside (C-3-G) against UVA-induced apoptosis and DNA fragmentation in a human keratinocyte cell line (HaCaT). Treatment of HaCaT cells with C-3-G before UVA irradiation inhibited the formation of apoptotic cells (61%) and DNA fragmentation (54%). We also investigated antioxidant properties of C-3-G in HaCaT cells against ROS formation at apoptotic doses of UVA; C-3-G inhibited hydrogen peroxide (H2O2) release (an indicator of cellular ROS formation) after UVA irradiation. Further confirmation of the potential of C-3-G to counteract UVA-induced ROS formation comes from our demonstration of its ability to enhance the resistance of HaCaT cells to the apoptotic effects of both H2O2 and the superoxide anion (O2*-), two ROS involved in UVA-oxidative stress. Furthermore, in terms of Trolox Equivalent Antioxidant Activity, C-3-G treatment led to a greater increase in antioxidant activity in the membrane-enriched fraction than in the cytosol (55% vs 19%). The protective effects against UVA-induced ROS formation can be attributed to the higher membrane levels of C-3-G incorporation. These encouraging in vitro results support further research into C-3-G (and other anthocyanins) as novel agents for skin photoprotection.

Protective Effects of Cyanidin-3-O-β-glucopyranoside Against UVA-induced Oxidative Stress in Human Keratinocytes¶

Ultraviolet-A (UVA) radiation causes significant oxidative stress because it leads to the generation of reactive oxygen species (ROS), leading to extensive cellular damage and eventual cell death either by apoptosis or necrosis. We evaluated the protective effects of cyanidin-3-O-beta-glucopyranoside (C-3-G) against UVA-induced apoptosis and DNA fragmentation in a human keratinocyte cell line (HaCaT). Treatment of HaCaT cells with C-3-G before UVA irradiation inhibited the formation of apoptotic cells (61%) and DNA fragmentation (54%). We also investigated antioxidant properties of C-3-G in HaCaT cells against ROS formation at apoptotic doses of UVA; C-3-G inhibited hydrogen peroxide (H2O2) release (an indicator of cellular ROS formation) after UVA irradiation. Further confirmation of the potential of C-3-G to counteract UVA-induced ROS formation comes from our demonstration of its ability to enhance the resistance of HaCaT cells to the apoptotic effects of both H2O2 and the superoxide anion (O2*-), two ROS involved in UVA-oxidative stress. Furthermore, in terms of Trolox Equivalent Antioxidant Activity, C-3-G treatment led to a greater increase in antioxidant activity in the membrane-enriched fraction than in the cytosol (55% vs 19%). The protective effects against UVA-induced ROS formation can be attributed to the higher membrane levels of C-3-G incorporation. These encouraging in vitro results support further research into C-3-G (and other anthocyanins) as novel agents for skin photoprotection.

Coenzyme Q10, a cutaneous antioxidant and energizer.

The processes of aging and photoaging are associated with an increase in cellular oxidation. This may be in part due to a decline in the levels of the endogenous cellular antioxidant coenzyme Q10 (ubiquinone, CoQ10). Therefore, we have investigated whether topical application of CoQ10 has the beneficial effect of preventing photoaging. We were able to demonstrate that CoQ10 penetrated into the viable layers of the epidermis and reduce the level of oxidation measured by weak photon emission. Furthermore, a reduction in wrinkle depth following CoQ10 application was also shown. CoQ10 was determined to be effective against UVA mediated oxidative stress in human keratinocytes in terms of thiol depletion, activation of specific phosphotyrosine kinases and prevention of oxidative DNA damage. CoQ10 was also able to significantly suppress the expression of collagenase in human dermal fibroblasts following UVA irradiation. These results indicate that CoQ10 has the efficacy to prevent many of the detrimental effects of photoaging.