In Situ Scanning Electron Microscopy Analysis of the Interfacial Failure of Oxide Scales on Stainless Steels and Its Effect on Sticking during Hot Rolling.

Despite various strategies to address sticking failure in stainless steels (STSs), difficulties in understanding its fundamental mechanisms hinder precise solutions during STS fabrication. This study investigated the effect of chromium (Cr) content on the microstructures and failure modes of oxide scales under a tensile load, simulating the hot-rolling process. The dynamic, real-time behavior of crack initiation, propagation, and interfacial delamination in the oxide scales under tension was analyzed using an in situ scanning electron microscopy (SEM) tensile test. With a high Cr content, iron (Fe) oxide and chromium(III) oxide (Cr2O3) form a layered structure, which is delaminated along the interfaces between the thin Cr2O3 layer and the bulk after perpendicular cracking. The saturated crack densities obtained from in situ SEM provide interfacial strength, while the elastic modulus and hardness obtained from nanoindentation provide vertical fracture strength. In combination with an ex situ elemental image analysis, the in situ SEM results reveal three different failure modes of the four different STSs. The results confirm that sticking failure is more likely to occur as the Cr content increases.

Comparative Insights into the Skin Beneficial Properties of Probiotic Lactobacillus Isolates of Skin Origin.

In recent times, probiotics have been emerging as one of valuable cosmetic resources. This work was undertaken to evaluate and compare the skin beneficial properties of three Lactobacillus strains, namely, L. plantarum SB202, L. fermentum SB101, and L. paraplantarum SB401, originally isolated from the healthy skins of Koreans. The Lactobacillus isolates were individually grown in MRS broth, and the corresponding cell-free conditioned mediums (CMs), LP202, LF101 and LPP401, were prepared for analyzing diverse cosmetic potentials at a comparative perspective. The superoxide radical and nitrite ion scavenging activities of the CMs were in the orders of LPP401 ≥ LF101 > LP202 and LPP401 > LF101≒LPP202, respectively. They attenuated the lipopolysaccharide-induced reactive oxygen species (ROS) and nitrite ion levels in RAW264.7 murine macrophages both in the order of LPP401 ≥ LF101 > LP202, implying their anti-inflammatory properties. They exhibited antityrosinase activities in the order of LPP401 > LF101 ≥ LP202 and diminished α-melanocyte-stimulating hormone-induced melanin levels in B16F10 melanoma cells in the order of LPP401≒LF101 > LP202, suggesting their skin whitening activities. They enhanced cornfield envelope formation in HaCaT keratinocytes in the order of LPP401 > LF101 > LP202. They inhibited the in vitro hyaluronidase and elastase activities in the orders of LPP401 > LP202 ≥ LF101 and LPP401 ≥ LP202 > LF101, respectively. Their enhancing properties on the synthesis of procollagen type I in normal human dermal fibroblasts were in the order of LF101≒LPP401 > >LP202. The CMs possess various cosmetic characteristics, such as antioxidant, skin whitening, antiaging, barrier improving, and anti-inflammatory activities. LPP401, the CM prepared from L. paraplantarum SB401, has been evaluated to be more desirable cosmetic resource than LP202 and LF101.

Clinical usefulness of T1-weighted MR cholangiography with Gd-EOB-DTPA for the evaluation of biliary complication after liver transplantation.

BACKGROUNDS/AIMS: Biliary complications continue to be the major morbidity and mortality causes following living donor liver transplantation (LT). Endoscopic retrograde cholangiopancreatography (ERCP) has been performed to identify the biliary leakage source. However, this can lead to retrograde cholangitis and pancreatitis, and is not sufficient to diagnose bile leakage from cuts' surface. This study aimed to describe the use of T1-Weighted Magnetic Resonance (MR) Cholangiography with Gd-EOB-DTPA (Primovist) examination for evaluating the bile duct complication following LT. METHODS: From March 2012 to December 2018, 869 adult LT were performed at the Seoul National University Hospital. Forty-three recipients had undergone MR Cholangiography with Gd-EOB-DTPA. We reviewed these cases with their clinical outcomes and described the utility of the MR cholangiography with Gd-EOB-DTPA. RESULTS: In radiologic examinations performed in the patients suspected of bile duct complication, 95% had bile leakage and stricture. Cut surface leakage was diagnosed in two cases, and biliary leakage from the anastomosis site was diagnosed in the others. Most patients with leakage had undergone percutaneous drainage and ERCP, which was performed to evaluate the bile secretion function of the hepatocytes. There was no contrast-enhanced bile duct image in one case with severe rejection, and it might have been related to hepatocyte secretary dysfunction. CONCLUSIONS: T1-Weighted MR Cholangiography with Gd-EOB-DTPA 40-minute delay examination is a feasible and safe non-invasive procedure for identifying biliary leakage sites.

Anti-Inflammatory, Barrier-Protective, and Antiwrinkle Properties of Agastache rugosa Kuntze in Human Epidermal Keratinocytes.

This work aimed to assess the skin-beneficial properties of Agastache rugosa Kuntze, an herbal medication used to treat different types of disorders in traditional folk medicine. The total phenolic compounds and total antiradical, nitrite scavenging, superoxide scavenging, antielastase, and antihyaluronidase activities of a hot water extract of A. rugosa Kuntze leaves (ARE) were spectrophotometrically determined. Intracellular reactive oxygen species (ROS) was fluorometrically quantitated using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). Inducible nitric oxide synthase (iNOS) and filaggrin were evaluated using Western analysis. Real-time quantitative RT-PCR was used to measure filaggrin mRNA. Caspase-14 activity was determined using a fluorogenic substrate. ARE contained the total phenolic content of 38.9 mg gallic acid equivalent/g extract and exhibited 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide radical, and nitrite scavenging activities with the SC50 values of 2.9, 1.4, and 1.7 mg/mL, respectively. ARE exerted suppressive activities on nitric oxide (NO) and ROS levels elevated by lipopolysaccharide (LPS) or tumor necrosis factor-α (TNF-α) in HaCaT keratinocytes. It attenuated the LPS-stimulated expression of iNOS. ARE augmented the UV-B-reduced filaggrin expression on both protein and mRNA levels and was capable of upregulating the UV-B-reduced caspase-14 activity. ARE inhibited in vitro elastase and hyaluronidase activities associated with the wrinkling process. ARE, at the concentrations used, did not interfere with the viability of HaCaT keratinocytes. These findings preliminarily imply that the leaves of A. rugosa possess desirable cosmetic potentials, such as anti-inflammatory, barrier protective, and antiwrinkle activities, which infers their skin healing potentials.

Wearable, Luminescent Oxygen Sensor for Transcutaneous Oxygen Monitoring.

We present a new concept for a wearable oxygen (O2) sensor for transcutaneous O2 pressure (tcpO2) monitoring by combining the technologies of luminescent gas sensing and wearable devices. O2 monitoring has been exhaustively studied given its central role in diagnosing various diseases. The ability to quantify the physiological distribution and real-time dynamics of O2 from the subcellular to the macroscopic level is required to fully understand mechanisms associated with both normal physiological and pathological conditions. Despite its profound biological and clinical importance, few effective methods exist for noninvasively quantifying O2 in a physiological setting. The wearable sensor developed here consists of three components: a luminescent sensing film attached onto skin by a carbon tape, an organic light-emitting diode (OLED) as a light source, and an organic photodiode (OPD) as a light detector. All the components are solution-processable and integrated on a plane in a bandage-like configuration. To verify the performance, tcpO2 variations by pressure-induced occlusion were measured in the lower arm and a thumb by the wearable sensor, and the results were comparable to those measured by a commercial instrument. In addition to its flexibility, other features of this sensor render it a potential low-cost solution for the simultaneous monitoring of tcpO2 in any part of a body.

Probiotic fermentation augments the skin anti-photoaging properties of Agastache rugosa through up-regulating antioxidant components in UV-B-irradiated HaCaT keratinocytes.

BACKGROUND: Agastache rugosa (Fisch. & C.A.Mey.) Kuntze (Korean mint) is used to treat diverse types of human disorders in traditional medicine. In recent years, its non-fermented leaf extract (ARE) has been shown to possess protective properties against ultraviolet-B (UV-B) radiation-induced photooxidative stress. The present work aimed to examine whether probiotic bacterial fermentation would potentiate the skin anti-photoaging activity of ARE or not, by comparing the protective properties of ARE and corresponding fermented extract (ARE-F) against UV-B radiation-induced photooxidative stress in HaCaT keratinocytes. METHODS: ARE-F was produced from ARE by the fermentation with Lactobacillus rhamnosus HK-9, a type of Gram-positive probiotic bacterial strain. Anti-photoaging activities were evaluated by analyzing reactive oxygen species (ROS), promatrix metalloproteinases (proMMPs), total glutathione (GSH) and total superoxide dismutase (SOD) in UV-B-irradiated HaCaT keratinocytes. Antiradical activity was determined using 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay. RESULTS: ARE-F contained higher attenuating activity on the UV-B-induced ROS generation than ARE. Similarly, ARE-F was able to diminish the UV-B-induced proMMP-9 and -2 more effectively than ARE. ARE-F displayed higher tendencies to augment the UV-B-reduced total GSH content and SOD activity than ARE. However, there were no significant difference between ARE and ARE-F in ABTS radical scavenging activities. CONCLUSIONS: The findings suggest that the UV-B radiation-protective activity of ARE is enhanced by probiotic bacterial fermentation, which might improve the therapeutic and cosmetic values of A. rugosa leaves.

Defensive Properties of Ginsenoside Re against UV-B-Induced Oxidative Stress through Up-Regulating Glutathione and Superoxide Dismutase in HaCaT Keratinocytes.

Ginseng is now used worldwide as a traditional Oriental medicine. Ginsenosides, also known as ginseng saponins, are responsible for most pharmacological efficacies of ginseng. This work aimed to assess the novel skin anti-photoaging potential of ginsenoside Re (Re), a protopanaxatriol-type ginsenoside, by analyzing reactive oxygen species (ROS), pro-matrix metalloproteinase-2 (proMMP-2) and -9 (proMMP-9), total glutathione (GSH), superoxide dismutase (SOD), and cellular viability in UV-B-irradiated HaCaT keratinocytes. When HaCaT cells were pretreated with Re prior to UV-B irradiation, Re significantly suppressed the UV-B-induced ROS elevation. It was also able to attenuate the UV-B-induced proMMP-2 and -9 elevations at both activity and protein levels. Re was capable of overcoming the UV-B-reduced total GSH content and SOD activity in concentration-dependent ways. Under the experimental conditions used, Re could interfere with cellular viabilities in neither non-irradiated nor UV-B-irradiated keratinocytes.

Protective properties of geniposide against UV-B-induced photooxidative stress in human dermal fibroblasts.

CONTEXT: Geniposide (genipin-1-O-ß-d-glucoside) is a major bioactive ingredient in the fruits of gardenia [Gardenia jasminoides J. Ellis (Rubiaceae)], a traditional herbal medicine in Asian countries. OBJECTIVE: This work assesses the skin anti-photoaging potential of geniposide in human dermal fibroblasts under UV-B irradiation. MATERIALS AND METHODS: The anti-photoaging property of geniposide, at varying concentrations (5, 12 and 30 µM) treated for 30 min prior to UV-B irradiation, was evaluated by analysing reactive oxygen species (ROS), promatrix metalloproteinase-2 (proMMP-2), glutathione (GSH), superoxide dismutase (SOD), nuclear factor erythroid 2-related factor 2 (Nrf2) and cellular viability. RESULTS: Geniposide suppressed the ROS elevation under UV-B irradiation, which was revealed using three ROS-sensitive fluorescent dyes. The use of 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), dihydroethidium (DHE) and dihydrorhodamine 123 (DHR-123) elicited the IC50 values of 10.5, 9.8 and 21.0 µM, respectively. Geniposide attenuated proMMP-2 at activity and protein levels that were elevated under UV-B-irradiation. Geniposide at 5, 12 and 30 µM augmented the UV-B-reduced total GSH content to 1.9 ± 0.1-, 2.2 ± 0.2- and 4.1 ± 0.2-fold, respectively. Geniposide at 5, 12 and 30 µM upregulated total SOD activity to 2.3 ± 0.1-, 2.5 ± 0.3- and 3.3 ± 0.3-fold, respectively, under UV-B irradiation. The UV-B-reduced Nrf2 levels were also upregulated by geniposide treatment. Geniposide, at the concentrations used, was unable to interfere with cellular viabilities under UV-B irradiation. DISCUSSION AND CONCLUSIONS: After the skin anti-photoaging potential of geniposide may be further verified, it can be utilized as a safer resource in the manufacture of effective anti-aging cosmetics.

Electronic Structure of C60/Zinc Phthalocyanine/V2O5 Interfaces Studied Using Photoemission Spectroscopy for Organic Photovoltaic Applications.

The interfacial electronic structures of a bilayer of fullerene (C60) and zinc phthalocyanine (ZnPc) grown on vanadium pentoxide (V2O5) thin films deposited using radio frequency sputtering under various conditions were studied using X-ray and ultraviolet photoelectron spectroscopy. The energy difference between the highest occupied molecular orbital (HOMO) level of the ZnPc layer and the lowest unoccupied molecular orbital (LUMO) level of the C60 layer was determined and compared with that grown on an indium tin oxide (ITO) substrate. The energy difference of a heterojunction on all V2O5 was found to be 1.3~1.4 eV, while that on ITO was 1.1 eV. This difference could be due to the higher binding energy of the HOMO of ZnPc on V2O5 than that on ITO regardless of work functions of the substrates. We also determined the complete energy level diagrams of C60/ZnPc on V2O5 and ITO.

Ginsenoside Rc protects against UVB­induced photooxidative damage in epidermal keratinocytes.

Ginsenoside Rc (Rc) is a major ginsenoside isolated from Panax ginseng, and has exhibited pharmacological effects on skin cells. The present study aimed to investigate the putative skin­protective properties of Rc, including its anti­photoaging and barrier function­protective effects, in human HaCaT keratinocytes exposed to UVB radiation. The protective properties of Rc were evaluated through the assessment of keratinocyte viability, reactive oxygen species (ROS) production, total glutathione (GSH) and superoxide dismutase (SOD) activity, caspase­14, matrix metalloproteinase (MMP)­2 and ­9 activity, and MMP­2, MMP­9 and filament aggregating protein (filaggrin) expression following UVB irradiation. Treatment with Rc was revealed to prevent the UVB­induced increase in ROS production and pro­MMP­2 and ­9 levels in HaCaT keratinocytes. In addition, treatment with Rc resulted in enriched GSH contents and enhanced SOD activity following exposure to UVB radiation. Furthermore, Rc treatment enhanced caspase­14 activity and counteracted the UVB­induced downregulation in filaggrin expression. However, no significant difference was identified between Rc­treated and normal groups in terms of keratinocyte viability, regardless of exposure to radiation. The present findings suggested that Rc may exert anti­photoaging and barrier function­protective effects in keratinocytes, and thus protect the skin against photooxidative stress induced by exposure to UV radiation.

Stereospecificity of ginsenoside Rg2 epimers in the protective response against UV-B radiation-induced oxidative stress in human epidermal keratinocytes.

Ginseng, referring to the dried roots of Panax ginseng C.A. Meyer, has been known as a famous traditional folkloric medicine in East Asian countries for a long time. In recent years, it has been gaining a worldwide popularity as a dietary herbal supplement. Ginsenosides are bioactive ingredients that are responsible for most pharmacological efficacies of ginseng. Ginsenoside Rg2 (Rg2), one of minor protopanaxatriol (PPT)-type ginsenosides, exists in two epimeric forms, 20(S)-ginsenoside Rg2 [20(S)-Rg2] and 20(R)-ginsenoside Rg2 [20(R)-Rg2]. This work was undertaken to assess and compare their skin anti-photoaging properties. When they were applied to HaCaT keratinocytes prior to the irradiation, 20(S)-Rg2 only could attenuate the UV-B-induced intracellular reactive oxygen species (ROS) elevation, which were detected using three fluorescent ROS dyes, such as 2',7'-dichlorodihydrofluorescein diacetate, dihydroethidium and dihydrorhodamine 123. 20(S)-Rg2 but not 20(R)-Rg2 significantly attenuated the UV-B-induced promatrix metalloproteinase-2 (proMMP-2) gelatinolytic activity and protein levels. Likewise, 20(S)-Rg2 only augmented the UV-B-reduced total glutathione (GSH) and superoxide dismutase (SOD) activity levels in a concentration-dependent manner. Neither of the two Rg2 epimers was cytotoxic to HaCaT keratinocytes, regardless of UV-B irradiation. Taken together, of the two Rg2 epimers, 20(S)-Rg2 only possesses the stereospecific protective properties against the UV-B-induced skin photoaging in HaCaT keratinocytes.

Attenuating properties of Agastache rugosa leaf extract against ultraviolet-B-induced photoaging via up-regulating glutathione and superoxide dismutase in a human keratinocyte cell line.

Agastache rugosa Kuntze, known as a Korean mint, is an herbal medicine that has been used for the treatment of diverse kinds of symptoms in traditional medicine. This work was undertaken to assess the protective properties of A. rugosa leaves against UV-B-induced photoaging in HaCaT keratinocytes. They were evaluated via analyzing reactive oxygen species (ROS), promatrix metalloproteinase-2 (proMMP-2) and -9 (proMMP-9), total glutathione (GSH), total superoxide dismutase (SOD), cellular viability, flavonoid content and in vitro radical scavenging activity. Total flavonoid content of ARE, a hot water extract of A. rugosa leaves, was 22.8±7.6mg of naringin equivalent/g ARE. ARE exhibited ABTS(+) radical scavenging activity with an SC50 of 836.9µg/mL. ARE attenuated the UV-B-induced ROS generation. It diminished the UV-B-induced elevation of proMMP-2 and -9 at both activity and protein levels. On the contrary, ARE was able to enhance the UV-B-reduced total GSH and total SOD activity levels. ARE, at the used concentrations, was unable to interfere with the cellular viabilities of HaCaT keratinocytes under UV-B irradiation. Taken together, ARE possesses a protective potential against UV-B-induced photoaging in HaCaT keratinocytes, possibly based upon up-regulating antioxidant components, including total GSH and SOD. These findings reasonably suggest the use of A. rugosa leaves as a photoprotective resource in manufacturing functional cosmetics.

Photoprotective properties of 20(S)-protopanaxatriol, an aglycone of ginseng saponins: Protection from ultraviolet-B radiation-induced oxidative stress in human epidermal keratinocytes.

Ginsenosides are responsible for diverse pharmacological properties ascribed to ginseng, a plant used in traditional medicine. Ginsenosides are classified into three categories: Protopanaxadiol, protopanaxatriol (PPT) and oleanolic acid. As an aglycone of PPT-type ginsenosides, PPT exists in two stereoisomeric forms, 20(S)-PPT and 20(R)­PPT. The 20(S)­PPT stereoisomer is a major metabolic product of PPT­type ginsenosides produced in the gastrointestinal tract. In the present study, 20(S)-PPT suppressed the elevation of reactive oxygen species in HaCaT cells following irradiation with ultraviolet (UV)­B. In addition, 20(S)­PPT inhibited UV­B­induced gelatinase activities of matrix metalloproteinase-2 and -9 in HaCaT cells, and suppressed UV­B­induced expression and secretion of these proteins. Accordingly, 20(S)­PPT restored the total glutathione levels in UV­B­irradiated keratinocytes. Taken together, these data indicated that 20(S)­PPT may possess photoprotective properties that combat the effects of UV­B radiation.

Ginsenoside Re improves skin barrier function in HaCaT keratinocytes under normal growth conditions.

Ginsenoside Re (Re), a major ginsenoside of ginseng, enhanced the cornified cell envelope (CE) formation in HaCaT keratinocytes under normal conditions. In HaCaT keratinocytes, Re was also able to upregulate filaggrin protein and caspase-14 activity in a concentration-dependent manner. These findings reasonably imply that Re possesses a desirable property of improving skin barrier function.

Ellagic acid plays a protective role against UV-B-induced oxidative stress by up-regulating antioxidant components in human dermal fibroblasts.

Ellagic acid (EA), an antioxidant polyphenolic constituent of plant origin, has been reported to possess diverse pharmacological properties, including anti-inflammatory, anti-tumor and immunomodulatory activities. This work aimed to clarify the skin anti-photoaging properties of EA in human dermal fibroblasts. The skin anti-photoaging activity was evaluated by analyzing the reactive oxygen species (ROS), matrix metalloproteinase-2 (MMP-2), total glutathione (GSH) and superoxide dismutase (SOD) activity levels as well as cell viability in dermal fibroblasts under UV-B irradiation. When fibroblasts were exposed to EA prior to UV-B irradiation, EA suppressed UV-B-induced ROS and proMMP-2 elevation. However, EA restored total GSH and SOD activity levels diminished in fibroblasts under UV-B irradiation. EA had an up-regulating activity on the UV-B-reduced Nrf2 levels in fibroblasts. EA, at the concentrations used, was unable to interfere with cell viabilities in both non-irradiated and irradiated fibroblasts. In human dermal fibroblasts, EA plays a defensive role against UV-B-induced oxidative stress possibly through an Nrf2-dependent pathway, indicating that this compound has potential skin antiphotoaging properties.

Protective properties of ginsenoside Rb3 against UV-B radiation-induced oxidative stress in HaCaT keratinocytes.

This work aimed to evaluate the skin anti-photoaging properties of ginsenoside Rb3 (Rb3), one of the main protopanaxdiol-type ginsenosides from ginseng, in HaCaT keratinocytes. The skin anti-photoaging activity was assessed by analyzing the levels of reactive oxygen species (ROS), pro-matrix metalloproteinase-2 (proMMP-2), pro-matrix metalloproteinase-9 (proMMP-9), total glutathione (GSH), and superoxide dismutase (SOD) activity as well as cell viability in HaCaT keratinocytes under UV-B irradiation. When HaCaT keratinocytes were exposed to Rb3 prior to UV-B irradiation, Rb3 exhibited suppressive activities on UV-B-induced ROS, proMMP-2, and proMMP-9 enhancements. On the contrary, Rb3 displayed enhancing activities on UV-B-reduced total GSH and SOD activity levels. Rb3 could not interfere with cell viabilities in UV-B-irradiated HaCaT keratinocytes. Rb3 plays a protective role against UV-B-induced oxidative stress in human HaCaT keratinocytes, proposing its potential skin anti-photoaging properties.

Contribution of ginsenoside Re to cellular redox homeostasis via upregulating glutathione and superoxide dismutase in HaCaT keratinocytes under normal conditions.

Ginsenoside Re (Re) is one of the main ginsenosides which are known to be responsible for diverse pharmacological properties of ginseng, widely used as a dietary supplement and a general tonic. The present work was undertaken to evaluate the antioxidative property of Re by analyzing reactive oxygen species (ROS), nitric oxide (NO), pro-matrix metalloproteinase-2 (proMMP-2) and -9 (proMMP-9), total glutathione (GSH) and superoxide dismutase (SOD) in normal, unstressed HaCaT keratinocytes. When HaCaT cells were subjected to Re, Re suppressed the ROS and NO levels in a concentration-dependent manner. Re at concentrations used exhibited no cytotoxicity on the cellular viabilities of HaCaT cells. It was also able to attenuate proMMP-2 and -9 at both activity and protein levels. On the contrary, Re was capable of enhancing the total GSH and SOD activity levels. The findings suggest that Re has an antioxidative property through the upregulation of some antioxidant components, including total GSH and SOD, in HaCaT keratinocytes, which then can play its underlying role in maintaining the cellular redox homeostasis.

Antioxidative properties of ginsenoside Ro against UV-B-induced oxidative stress in human dermal fibroblasts.

Ginsenoside Ro (Ro), an oleanolic acid-type ginsenoside, exhibited suppressive activities on reactive oxygen species (ROS) and matrix metalloproteinase-2 (MMP-2) elevation in UV-B-irradiated fibroblasts. Ro could overcome the reduction of the total glutathione (GSH) contents in UV-B-irradiated fibroblasts. Ro could not interfere with cell viabilities in UV-B-irradiated fibroblasts. Collectively, Ro possesses a potential skin anti-photoaging property against UV-B radiation in fibroblasts.

Protective properties of ginsenoside Rb1 against UV-B radiation-induced oxidative stress in human dermal keratinocytes.

Ginsenosides, also known as ginseng saponins, are responsible for most pharmacological effect of ginseng. Ginsenoside Rb1 (Rb1) exerts a variety of pharmacological properties, including anti-inflammatory, antistress, anti-aging and anti-neurodegenerative activities. The aim of the present work was to assess the skin anti-photoaging properties of Rb1 in human dermal keratinocyte HaCaT cells. The anti-photoaging activity was evaluated by analyzing the levels of reactive oxygen species (ROS) and matrix metalloproteinases (MMPs) as well as cell viability for HaCaT cells under UV-B irradiation. Rb1 was able to suppress the ROS levels which were elevated under UV-B irradiation, and unable to influence cellular survival in UV-B-irradiated HaCaT cells. Rb1 diminished the enhancement of MMP-2 gelatinolytic activity in conditioned medium, which corresponded with the decreased MMP-2 protein levels in both conditioned medium and cellular lysate prepared from UV-B-irradiated HaCaT cultures. Rb1 could restore the total glutathione (GSH) and superoxide dismutase (SOD) activity diminished in UV-B-irradiated HaCaT cells. Ginsenoside Rb1 possesses skin anti-photoaging properties through scavenging ROS and decreasing MMP-2 levels possibly by enhancing antioxidant activity in keratinocytes under UV-B irradiation.

Ginsenoside Rb2 Attenuates UV-B Radiation-Induced Reactive Oxygen Species and Matrix Metalloproteinase-2 through Upregulation of Antioxidant Components in Human Dermal Fibroblasts.

AIMS: The antiphotoaging activities of ginsenoside Rb2 on the skin, one of the predominant protopanaxadiol-type ginsenosides, were evaluated in cultured human dermal fibroblasts. METHODS: The antiphotoaging activity was examined by analyzing the levels of reactive oxygen species (ROS), matrix metalloproteinase-2 (MMP-2), total glutathione (GSH) and superoxide dismutase (SOD) activity as well as cell viability for fibroblasts under UV-B irradiation. RESULTS: When cultured fibroblasts were exposed to Rb2 prior to UV-B irradiation, Rb2 displayed suppressive activities on UV-B-induced ROS elevation and MMP-2 on both activity and protein levels, while it exhibited an enhancing activity on total GSH level and SOD activity diminished by UV-B irradiation. However, Rb2 could not interfere with cell viabilities in UV-B-irradiated fibroblasts. CONCLUSION: Ginsenoside Rb2 plays a photoprotective role against UV-B-induced oxidative stress in human dermal fibroblasts, which implies its skin antiphotoaging potential.