Melanin Synthesis In B16F10 Cells Research Articles

Antimelanogenic potential of brewer's spent grain extract through modulation of the MAPK/MITF axis

Beer brewing produces >39 million tons of brewer's spent grain (BSG) per year worldwide. Although BSG is rich in protein, fiber, and phytochemicals, it is mainly used as livestock feed, and some is discarded. In this study, we attempted to assess the antimelanogenesis effects of BSG and identify the functional components. To this end, we investigated the antioxidant and antimelanin synthesis effects of a BSG extract (BSGE). The results showed that BSGE has high DPPH radical-scavenging activity and inhibited α-MSH-induced melanin synthesis in B16F10 cells cultured in both 2D and 3D environments. BSGE also reduced the expression levels of MITF, TRP-1, TRP-2, and tyrosinase in B16F10 cells by regulating the MAPK pathway. We confirmed the skin-whitening effect of BSGE in 3D reconstituted human skin and zebrafish embryo models. HPLC analysis showed that BSGE contains ferulic acid and p-coumaric acid, which are known to have whitening effects. Thus, BSGE can be used in multifunctional cosmetics as a sustainable ingredient with antioxidant and skin-whitening properties.

Preparation of niacinamide imprinted starch-based biomaterials for treating of hyperpigmentation

The aim of this study was to prepare niacinamide (NA) imprinted biomaterials for treating hyperpigmentation using mungbean starch (MS), PVA, and plasticizers (glycerol (GL) and citric acid (CA)). Biomaterials and NA were characterized by FE-SEM, FT-IR, and 1H NMR. To evaluate the applicability of the NA imprinted biomaterials for a transdermal drug delivery system (TDDS), NA release experiment was conducted in different pH and temperature conditions. Results of NA release properties indicated that NA was released about 99 % rapidly in the initial 10 min. NA release in low pH and high temperature was also higher than that in high pH and low temperature. The determination of experimental conditions and the analysis of NA release results were achieved using response surface methodology (RSM). Results of NA release using artificial skin indicated that NA release from NA imprinted biomaterials was increased at a relatively steady rate for 90 min. To verify for treating hyperpigmentation of the prepared biomaterials, tyrosinase inhibitory and antioxidant inhibitory were performed. Results indicated that NA imprinted biomaterials with the addition of CA exhibited 55.8 % of tyrosinase inhibitory and 73.0 % of antioxidant inhibitory. In addition, their ability to inhibit melanin synthesis in B16F10 cells was evaluated.

Anti-Melanogenic Activity of Calocedrus formosana Wood Essential Oil and Its Chemical Composition Analysis.

Calocedrus formosana (Cupressaceae) is one of the five precious woods of Taiwan. In this study, we investigated the anti-melanogenic activity of C. formosana wood essential oil (CFEO) and its bioactive components in vitro. Initially, CFEO exhibited strong mushroom tyrosinase activity in the cell-free mushroom tyrosinase assay system with an IC50 value of 2.72 µg/mL. Next, treatment with CFEO significantly as well as dose-dependently reduced a combination of α-melanocyte-stimulating hormone and forskolin (α-MSH-FSK)-induced melanin synthesis in B16-F10 cells. Indeed, 80 μg/mL CFEO completely inhibited melanin production, which is similar to that of control cells. Further studies revealed that treatment with CFEO significantly inhibited melanogenesis regulatory proteins, including TRP-1, TRP-2, and MITF, whereas tyrosinase was unaffected by either α-MSH-FSK or CFEO. In addition, the composition of the CFEO was characterized. The major components of CFEO were α-terpineol (23.47%), shonanic acid (10.45%), terpinen-4-ol (12.23%), thymol (5.3%), piperitone (3.44%), berbenone (2.81%), thujic acid (1.65%), and chaminic acid (0.13%). Among them, shonanic acid (1), thujic acid (2), and chaminic acid (3) were uncommon constitutes in essential oils, which could be the index compounds of CFEO, and the structure of these compounds were confirmed by spectral analysis. Furthermore, we found that thymol is an active ingredient responsible for CFEO’s anti-melanogenic activity. Based on these results, we suggest that CFEO or thymol could be a potential candidate for the development of skin whitening products for cosmetic purposes.

High Therapeutic and Esthetic Properties of Extracellular Vesicles Produced from the Stem Cells and Their Spheroids Cultured from Ocular Surgery-Derived Waste Orbicularis Oculi Muscle Tissues.

Extracellular vesicles (EVs) are paracrine factors that mediate stem cell therapeutics. We aimed at evaluating the possible therapeutic and esthetic applications of EVs prepared from the waste human facial tissue-derived orbicularis oculi muscle stem cells (OOM-SCs). OOM-SCs were isolated from the ocular tissues (from elders and youngsters) after upper eyelid blepharoplasty or epiblepharon surgeries. EVs were prepared from the OOM-SCs (OOM-SC-EVs) and their three-dimensional spheroids. OOM-SCs showed a spindle-like morphology with trilineage differentiation capacity, positive expression of CD105, CD 90, and CD73, and negative expression of CD45 and CD34, and their stem cell properties were compared with other adult mesenchymal stem cells. OOM-SC-EVs showed a high inhibitory effect on melanin synthesis in B16F10 cells by blocking tyrosinase activity. OOM-SC-EVs treatment led to a significant attenuation of senescence-associated changes, a decrease in reactive oxygen species generation, and an upregulation of antioxidant genes. We demonstrated the regeneration activity of OOM-SC-EVs in in vitro wound healing of normal human dermal fibroblasts and upregulation of anti-wrinkle-related genes and confirmed the therapeutic potential of OOM-SC-EVs in the healing of the in vivo wound model. Our study provides promising therapeutic and esthetic applications of OOM-SC-EVs, which can be obtained from the ocular surgery-derived waste human facial tissues.

Cefotaxime sodium inhibited melanogenesis in B16F10 cells by cAMP/PKA/CREB pathways

Cefotaxime sodium (CTX) was found to inhibit the activity of mushroom tyrosinase. The present study was conducted to investigate its inhibition of melanogenesis in B16F10 cells. CTX was found to inhibit melanin synthesis in B16F10 cells at a concentrations less than 200 μmol/L with no cytotoxicity. CTX reduced tyrosinase activity in a dose-dependent manner. CTX inhibited melanin formation from the results of the Masson-Fontana melanin staining and transmission electron microscope CTX influenced melanin production by influencing the expression of the proteins MITF, TRP-1, TRP-2 and TYR. Furthermore, CTX could down-regulate the intracellular cAMP/PKA/CREB contents, affecting the expression of MITF, and further down-regulate the expression of TRP-1, TRP-2 and TYR to inhibit melanin. Furthermore, CTX has been shown to inhibit body pigmentation in zebrafish. These results may provide a theoretical foundation for the new application of CTX in the field of medicine.

The anti-melanogenic effects of 3-O-ethyl ascorbic acid via Nrf2-mediated α-MSH inhibition in UVA-irradiated keratinocytes and autophagy induction in melanocytes

3-O-ethyl ascorbic acid (EAA) is an ether-derivative of ascorbic acid, known to inhibit tyrosinase activity, and is widely used in skincare formulations. Nevertheless, the molecular mechanisms underlying the EAA's effects are poorly understood. Here, the anti-melanogenic activity of EAA was demonstrated through Nrf2-mediated α-MSH inhibition in UVA-irradiated keratinocytes (HaCaT) and autophagy induction and inhibition of α-MSH-stimulated melanogenesis in melanocytes (B16F10). EAA pretreatment increased the HaCaT cell viability but suppressed ROS-mediated p53/POMC/α-MSH pathways in UVA-irradiated cells. Further, the conditioned medium from EAA-pretreated and UVA-irradiated HaCaT cells suppressed the MITF-CREB-tyrosinase pathways leading to the inhibition of melanin synthesis in B16F10 cells. EAA treatment increased nuclear Nrf2 translocation via the p38, PKC, and ROS pathways leading to HO-1, γ-GCLC, and NQO-1 antioxidant expression in HaCaT cells. However, Nrf2 silencing reduced the EAA-mediated anti-melanogenic activity, evidenced by impaired antioxidant gene expression and uncontrolled ROS (H202) generation following UVA irradiation. In B16F10 cells, EAA-induced autophagy was shown by enhanced LC3-II levels, AVO formation, Beclin-1 upregulation, and activation of p62/SQSTM1. Further, EAA-induced anti-melanogenic activity was substantially decreased in autophagy inhibitor (3-MA) pretreated or LC3 knockdown B16F10 cells. Notably, transmission electron microscopy data showed increased melanosome-engulfing autophagosomes in EAA-treated B16F10 cells. Moreover, EAA also down-regulated MC1R, TRP-1/-2, tyrosinase expressions, and melanin synthesis by suppressing the cAMP-CREB-mediated MITF expression in B16F10 cells stimulated with α-MSH. In vivo studies on the zebrafish model further confirmed that EAA inhibited tyrosinase expression/activity and endogenous pigmentation. In conclusion, 3-O-ethyl ascorbic acid is an effective skin-whitening agent and could be used as a topical agent for cosmetic purposes.

Antimelanogenesis Effects of Theasinensin A.

Theasinensin A (TSA) is a major group of catechin dimers mainly found in oolong tea and black tea. This compound is also manufactured with epigallocatechin gallate (EGCG) as a substrate and is refined after the enzyme reaction. In previous studies, TSA has been reported to be effective against inflammation. However, the effect of these substances on skin melanin formation remains unknown. In this study, we unraveled the role of TSA in melanogenesis using mouse melanoma B16F10 cells and normal human epidermal melanocytes (NHEMs) through reverse transcription polymerase chain reaction (RT-PCR), Western blotting analysis, luciferase reporter assay, and enzyme-linked immunosorbent assay analysis. TSA inhibited melanin formation and secretion in α-melanocyte stimulating hormone (α-MSH)-induced B16F10 cells and NHEMs. TSA down-regulated the mRNA expression of tyrosinase (Tyr), tyrosinase-related protein 1 (Tyrp1), and Tyrp2, which are all related to melanin formation in these cells. TSA was able to suppress the activities of certain proteins in the melanocortin 1 receptor (MC1R) signaling pathway associated with melanin synthesis in B16F10 cells: cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), protein kinase A (PKA), tyrosinase, and microphthalmia-associated transcription factor (MITF). We also confirmed α-MSH-mediated CREB activities through a luciferase reporter assay, and that the quantities of cAMP were reduced by TSA in the enzyme linked immunosorbent assay (ELISA) results. Based on these findings, TSA should be considered an effective inhibitor of hyperpigmentation.

Anti-melanogenic effects of epigallocatechin-3-gallate (EGCG), epicatechin-3-gallate (ECG) and gallocatechin-3-gallate (GCG) via down-regulation of cAMP/CREB /MITF signaling pathway in B16F10 melanoma cells

Tea catechins, the main bioactive polyphenols in green tea, are well known for their health promoting effects. Previous studies have shown that gallocatechin-3-gallate (GCG), epigallocatechin-3-gallate (EGCG) and epicatechin-3-gallate (ECG) exerted strong inhibitory effects on mushroom tyrosinase activity in vitro, whilst EGCG inhibited melanogenesis in vivo, yet the underlying mechanisms are not entirely clear. In this study, we (i) evaluated and compared the inhibitory effects of the main tea catechins (GCG, EGCG, and ECG) on melanogenesis in B16F10 melanoma cells, and (ii) explain the underlying mechanisms. The results showed that the tea catechins significantly suppressed tyrosinase activity and melanin synthesis in B16F10 cells, where the effects of ECG > EGCG > GCG. Interestingly, the inhibitory effects of the catechins were stronger than those of arbutin (AT), a well-known depigmenting agent. Moreover, GCG, EGCG, and ECG regulated the melanogenesis of B16F10 cells through the cAMP/CREB/MITF pathway. These results revealed catechins could be used as anti-melanogenic agents to protect cells from abnormal melanogenesis.

Regulation of Melanogenesis by the Amino Acid Transporter SLC7A5

Integration of chromatin immunoprecipitation-sequencing and microarray data enabled us to identify previously unreported MITF-target genes, among which the amino acid transporter SLC7A5 is also included. We reported that small interfering RNA-mediated SLC7A5 knockdown decreased pigmentation in B16F10 cells but neither affected morphology nor dendricity. Treatment with the SLC7A5 inhibitors 2-amino-2-norbornanecarboxylic acid (BCH) or JPH203 also decreased melanin synthesis in B16F10 cells. Our findings indicated that BCH was as potent as reference depigmenting agent, kojic acid, but acted through a different pathway not affecting tyrosinase activity. BCH also decreased pigmentation in human MNT1 melanoma cells or normal human melanocytes. Finally, we tested BCH on a more physiological model, using reconstructed human epidermis and confirmed a strong inhibition of pigmentation, revealing the clinical potential of SLC7A5 inhibition and positioning BCH as a depigmenting agent suitable for cosmetic or dermatological intervention in hyperpigmentation diseases.

Cambios en el perfil de compuestos fenólicos, actividad antioxidante y antimelanogénica de órganos de Petasites japonicas bajo diferentes métodos de extracción

Petasites japonicus, a perennial flowering plant belonging to the Asteraceae family, has long been used in traditional herbal medicine for treating various diseases. The present study was conducted to investigate the effect of extraction methods including microwave-assisted extraction, autoclave-assisted extraction, and hot water extraction on the polyphenolic composition, antioxidant activity, and anti-melanogenic activity of P. japonicus leaves, stems, and roots. In comparison with other samples, leaf extracts exhibited strong DPPH radical scavenging activity, reducing power activity, and hydrophilic oxygen radical scavenging activity. In addition, the leaf extracts significantly suppressed α-MSH-induced melanin synthesis in B16F10 cells. Quantitative real-time PCR, western blot, and cellular reactive oxygen species (ROS) analyses indicated that the anti-melanogenic effect of leaf extracts obtained by hot water extraction may result from the inhibition of ROS generation and the downregulation of tyrosinase expression in B16F10 cells. Furthermore, the extraction methods differentially affected the content of polyphenolic compounds and bioavailability of P. japonicus extracts. Taken together, the antioxidant activity and anti-melanogenic effect of leaf hot water extracts suggest that the leaves of P. japonicus could be a beneficial source of natural antioxidants for skincare products.

생맥산가미방 추출물이 멜라닌 생합성 저해 효과와 SOD 활성에 미치는 연구

This study aims to evaluate the effects of Shengmaisan (SMS) and three types of ShengmaisanJiaweifang on the inhibitory effect of melanin synthesis in B16F10 cells, the mechanism of action through tyrosinase, and the antioxidant effect through superoxide dismutase (SOD) activity. In this study, we used ShengmaisanJiaweifangs (SMS, SMSRR, SMSAD, SMSAR) to research the whitening effects in B16F10 cell lines. Shengmaisan (SMS) was a herbal medicine composed of Ginseng Radix, Liriopis Tuber, and Schisandrae Fructus. ShengmaisanJiaweifangs included SMSRR (SMS added with Rehmanniae Radix), SMSAD (SMS added with Asparagi Radix) and SMSAR (SMS added with Astragali Radix). We measured the cell viability, the inhibition rate of the melanin biosynthesis, and the activity of tyrosinase and SOD in malignant melanoma, B16F10 cells, to survey the whitening effect and the mechanism of the impact on the sample. As a result, SMSRR significantly suppressed the cell viability of B16F10 at more than 500 ㎍/㎖ and significantly inhibited the generation of melanin induced by α-MSH at more than 250 ㎍/㎖. SMSRR (500 ㎍/㎖) decreased the activity of tyrosinase while increased the activity of SOD. Therefore, we considered that the SMSRR would be able to produce high value-added products more SMS if used as a commercial.

Tobramycin Promotes Melanogenesis by Upregulating p38 MAPK Protein Phosphorylation in B16F10 Melanoma Cells.

Tobramycin is an aminoglycoside-based natural antibiotic derived from Streptomyces tenebrarius, which is primarily used for Gram-negative bacterial infection treatment. Although tobramycin has been utilized in clinical practice for a long time, it has exhibited several side effects, leading to the introduction of more effective antibiotics. Therefore, we conducted our experiments focusing on new possibilities for the clinical use of tobramycin. How tobramycin affects skin melanin formation is unknown. This study used B16F10 melanoma cells to assess the effect of tobramycin on melanin production. After cytotoxicity was assessed by MTT assay, melanin content and tyrosinase activity analyses revealed that tobramycin induces melanin synthesis in B16F10 cells. Next, Western blot analyses were performed to elucidate the mechanism by which tobramycin increases melanin production; phosphorylated p38 protein expression was upregulated. Protein inhibitors have been used to elucidate the mechanism of tobramycin. Kanamycin A and B are structurally similar to tobramycin, and 2-DOS represents the central structure of these antibiotics. The effects of these substances on melanogenesis were evaluated. Kanamycin A reduced melanin production, whereas kanamycin B and 2-DOS had no effect. Overall, our data indicated that tobramycin increases melanin production by promoting p38 protein phosphorylation in B16F10 melanoma cells.

Nanoemulsified adlay bran oil reduces tyrosinase activity and melanin synthesis in B16F10 cells and zebrafish.

The efficacy of oily components is often difficult to evaluate due to their incompatibility with most models. Here, we emulsified adlay bran oil (ABO), processed it to a nanoscale, and investigated its anti‐hyperpigmentation efficacy, assessed for its inhibitory effects against tyrosinase activity and melanin production, in an in vitro system (mouse melanoma B16F10 cells) and an in vivo system (zebrafish embryos). ABO induced dose‐dependent reductions in tyrosinase activity and melanin production in both the melanoma cells and zebrafish, without affecting viability. The efficacy of ABO was strongly influenced by emulsion particle size in the zebrafish but not in the cells. These results indicate that ABO has potential as a tyrosinase inhibitor and anti‐hyperpigmentation agent and that the emulsion system is an effective method for delivering the bioactive components of ABO to living systems that could be utilized for other oily components.

Tetrahydrocurcumin Inhibits α-MSH-induced Melanogenesis via GSK3β Activation in B16F10 Melanoma Cells

Tetrahydrocurcumin (THC) has been used as a component of skin whitening cream. However, very little is known about the mechanisms for how THC regulates melanogenesis. The aim of the present study was to investigate mechanisms involved in the regulation of melanogenesis by THC using B16F10 murine melanoma cells. B16F10 cells were treated with various concentrations of THC (0–30 µg/mL) in the presence of 0.1 nM ±-melanocyte stimulating hormone (±-MSH). Total melanin content; intracellular tyrosinase activity; and levels of melanogenic proteins, i.e., microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein 1 (TYRP1), and signaling proteins, i.e, Akt, glycogen synthase kinase 3β (GSK3β), and β-catenin, were analyzed. Change in cell morphology was also observed. THC-Treatment caused a significant and dose-dependent decrease in total melanin content compared to control cells treated with α-MSH alone. At the early stage of melanogenesis, when melanin secretion was minimal, THC-treatment caused decreases in the activity of tyrosinase and the levels of tyrosinase and MITF proteins. Conversely, at the late stage of melanogenesis, when melanin secretion was evidently exhibited in control cells, remarkable increases in the intracellular levels of tyrosinase and TYRP1, the melanosomal proteins, were observed in THC-treated cells. THC-treatment caused decreases in Akt and GSK3β phosphorylation and β-catenin content. A significant alteration of cell morphology, i.e. elongation and loss of dendritic structure, was also observed. The present study demonstrated that THC-treatment inhibited α-MSH-induced melanin synthesis in B16F10 cells by downregulating MITF and tyrosinase proteins and decreasing tyrosinase activity. In addition, THC inhibited secretion of melanosomes, which appears to be associated with cell morphology alteration accompanying a loss of dendritic structure. THC caused decreases in the phosphorylation of Akt and GSK3β and the content of β-catenin, suggesting involvement of GSK3β activation and subsequent attenuation of β-catenin signaling in the anti-melanogenic effects of THC.

Anti-melanogenic effects of oyster hydrolysate in UVB-irradiated C57BL/6J mice and B16F10 melanoma cells via downregulation of cAMP signaling pathway

Ethnopharmacological relevancePacific oyster (Crassostrea gigas) has been used to treat pigmentary disorders such as freckles, melasma, and moles in Korea. Aim of the studyWe aimed to investigate the inhibitory effects of oyster hydrolysate (OH) on melanogenesis in B16F10 melanoma cells and UVB-irradiated C57BL/6J mice. Material and methodsThe molecular weight distribution and peptide sequences of OH were detected using MALDI-TOF and UHPLC. To evaluate the anti-melanogenic effects of OH, cell viability, melanin content, tyrosinase activity, intracellular cyclic adenosine monophosphate (cAMP) and protein expressions levels were measured in B16F10 cells. In addition, OH was orally administered to UVB-irradiated mice for 9 weeks. After sacrificing the mice, the whitening effects of OH were evaluated based on histological observations and protein expression levels. ResultsIn B16F10 cells, OH decreased melanin content and tyrosinase activity in a dose-dependent manner. OH exhibited anti-melanogenic activities via downregulation of cAMP signaling pathway, which consequently decreased melanin synthesis.In UVB-irradiated mice groups, OH decreased the number of active melanocytes and melanin granules. The expression of tyrosinase-related proteins and microphthalmia-associated transcription factor (MITF) decreased in the OH-administered groups. ConclusionsThese results show that OH inhibits melanin synthesis in B16F10 cells via downregulation of cAMP signaling pathway and in UVB-irradiated mice, by decreasing the number of active melanocytes and melanin granules.

Protective effects of tetrahydrocurcumin (THC) on fibroblast and melanoma cell lines in vitro: it's implication for wound healing.

The aim of this study was to investigate the role of tetrahydrocurcumin (THC) against various skin health parameters using in vitro human foreskin fibroblast and melanoma cell lines (i.e. HFF-1 and B16-F10). The study was assessed using cell viability by MTT assay, identification of extracellular matrix component in HFF-1 cell line (i.e. collagen, elastin and hyaluronic acid), melanin synthesis in B16-F10 cells, cell viability against UVB-induced stress in HFF-1 cells, and in vitro wound healing by the scratch assay. THC was found to be safe and nontoxic up to the concentration of 10µg/mL with improved level of collagen (37.90%), elastin (90.1%), and hyaluronic acid (74.19%) at 1µg/mL. Besides, melanin was significantly inhibition by 78.5% at the lowest THC concentration of 0.1µg/mL. UVB-protection rate was significantly improved by 61.2% and improved cell viability by THC in HFF-1 cells, which indicated protection from photoaging. In addition, THC showed significant wound healing activity (78.51%) and greater migration of fibroblast in HFF-1 cells at different time period. It can be concluded from the study that THC can protect the skin matrix with improved extracellular component synthesis and would healing via collagen synthesis in the skin, which improved the skin elasticity and tightness. Overall, it might be suggested that THC can be used as a safe skin whitening agent, wounds management, cosmetic applications, and treating various skin-related disorders.

Benzo(a)pyrene represses melanogenesis in B16F10 mouse melanoma cells

Benzo(a)pyrene (BaP) is a chemically based polycyclic aromatic hydrocarbon (PAH) that is readily absorbed by the skin. BaP is metabolized to BaP-diol-epoxide by cytochromes P-450 1A1/2 (CYP1A1/2) and cytochromes P-450 1B1 (CYP1B1) in the cytosol. BaP and its metabolites induce genotoxicity and cancer. Although BaP easily accumulates in melanin-containing tissues as well as other tissue types, the effects of BaP on melanocytes are not fully understood. Here, we show that 40-100 µM BaP represses melanin synthesis in B16F10 cells. The decrease of melanin contents is induced by tyrosinase activity in BaP-exposed B16F10. However, this repression of melanin synthesis is not induced by direct inhibition of tyrosinase in in vitro assay. Therefore, we show whether BaP regulated melanin synthesis-related enzyme. BaP regulates melanin synthesis by Tyr and Tyrpl expression. In addition, these genes expression is down-regulated by Mitf repressed by BaP. Importantly, the repression was provoked in the absence and presence of α-melanocyte stimulating hormone (α-MSH). Therefore, we hypothesize BaP interrupts the UV protection mechanism by repressing melanin synthesis in the skin. Taken together our results have revealed new side effects that exposure of BaP abolished melanin synthesis in melanocytes.

Study on Pharmacological Activation as Cosmetic Material of Gentianae scabrae bunge Extract

In this study, we investigated the effect of ethanol extracts from Gentianae scabrae bunge (GSB) on the activities of antioxidant, whitening and anti-inflammation. Viability of cells was measured by neutral red (NR) assay, and inhibitory effects of GSB on melanin synthesis was determined the melanin production in B16F10 cells. The expression level of matrix metalloproteinase-1 (MMP-1) in media was analyzed by ELISA kit, and nitric oxide (NO) production in RAW264.7 cells was monitored by measuring the nitrite content in culture medium. GSB showed highly efficacy in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and significantly reduced melanin synthesis in B16F10 cells. MMP-1 production in UVB-stimulated human dermal fibroblast (HDF) cells was inhibited by GSB treatments. NO production was suppressed by the treatment of GSB in LPS-stimulated RAW264.7 cells. From this results, it was indicated that GSB could be utilized as anti-aging and whitening cosmetic ingredients.

용담화 에탄올 추출물의 항노화 작용 연구

Objective : The goal of this study is to identify the effects of extract of Gentianae sino-ornata (GSO) on the anti-oxidative activity of skin. For this purpose, several functions of GSO were analyzed in terms of skin-lightening activity and wrinkle improvement. Methods : Cell viability was measured by neutral red (NR) assay, and GSO showed highly efficacy in DPPH radical scavenging activity. The level of tyrosinase and matrix metalloproteinase-1 (MMP-1) in media was analyzed by ELISA kit, and the expressions of p-JNK and p-ERK was measured by Western blot. To elucidate inhibitory effects of GSO on melanin synthesis, I determined the tyrosinase activity and melanin production in B16F10 cells. Results : MMP-1 production in UVB-stimulated HDF cells was inhibited by G SO treatments, and also GSO inhibited protein expression levels of p-JNK and p-ERK. GSO significantly reduced tyrosinase activity and melanin synthesis in B16F10 cells. Conclusions : From these results, GSO appears to be effective on skin elasti city increase, wrinkle improvement, whitening as anti-aging activity.

Ardisia crenata extract stimulates melanogenesis in B16F10 melanoma cells through inhibiting ERK1/2 and Akt activation.

Melanin protects the skin against ultraviolet radiation by scattering incoming light and absorbing diverse free radicals. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. The present study investigated the effect of a methanol extract of Ardisia crenata (AC) on melanogenesis in B16F10 cells. Treatment of cultured B16F10 cells with AC extract (10, 20 and 40 µg/ml) stimulated an increase in melanin levels in a concentration-dependent manner, without cytotoxicity. Tyrosinase is key in the regulation of melanin production, thus the effect of AC extract on tyrosinase activity and protein expression was analyzed. AC extract was observed to significantly increase tyrosinase activity and protein expression in B16F10 cells. Furthermore, AC extract was found to markedly increase the protein expression of microphthalmia-associated transcription factor, which is an important transcription factor involved in tyrosinase gene expression. In addition, AC extract (40 µg/ml) was observed to suppress the activation of extracellular signal-regulated kinase (ERK) and Akt, which negatively regulate melanin synthesis in B16F10 cells. In conclusion, to the best of our knowledge, the present study is the first to show that a methanol extract of AC stimulates melanogenesis by increasing tyrosinase expression via the inhibition of ERK and Akt. Thus, methanol extract of AC may be a potential treatment for hypopigmentation diseases and may be a candidate for skin-tanning cosmetic products.