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Melanin provides photoprotection against UV irradiation, but excessive melanin accumulation can cause several problems such as darkened skin, melasma, and freckles. Although many anti-melanogenic agents have been developed for skin-whitening cosmetics, safety issues have been raised regarding these products. As natural substances are often non-toxic and are considered by some to be safer than synthetic compounds, various attempts have been made to synthesize active derivatives from natural substances. In this study, we evaluated the anti-melanogenic effects of four synthesized derivatives (compound 2a, 2b, 2c, and 2d) of kojic and hydroxycinnamic acids which are natural anti-melanogenic substances. Three of these derivatives (2a, 2b, and 2c) inhibited tyrosinase, which catalyzes a rate-limiting step of melanogenesis. Additionally, cell viability and melanin formation were investigated using B16F10 melanoma cells. Compounds 2b and 2c exhibited cytotoxicity towards B16F10 melanoma cells, while compound 2a caused a significant decrease in melanin formation without cytotoxicity. Thus, compound 2a may be viable as a potent skin-whitening agent derived from natural compounds.

Adiponectin is an adipocytokine with insulin-sensitizing, anti-inflammatory, anti-atherosclerotic, and anti-aging properties. Compounds with the ability to promote adiponectin secretion are of interest for the development of anti-aging drugs to improve skin-aging phenotypes. In the phenotypic assay to measure adiponectin secretion during adipogenesis in human adipose tissue-derived mesenchymal stem cells (hAT-MSCs), kojyl cinnamate ester derivatives increased adiponectin secretion. A target identification study showed that the kojyl cinnamate ester derivatives competitively bound to peroxisome proliferator-activated receptor α/γ (PPARα/γ). The upregulation of adiponectin production induced by kojyl cinnamate ester derivatives was significantly correlated with PPARα and PPARγ binding activities. Kojyl cinnamate ester derivatives significantly increased the transcription of genes encoding cholesterol and fatty acid synthesizing enzymes in hAT-MSCs. Notably, the kojyl cinnamate esters upregulated the gene transcription of lipid metabolic enzymes in human epidermal keratinocytes, which are important in the integrity of skin permeability barrier. In addition, the kojyl cinnamate esters that function as PPARα/γ dual modulators inhibited ultraviolet B irradiation-induced inflammation in human epidermal keratinocytes. Therefore, kojyl cinnamate ester derivatives are a novel class of PPARα/γ dual agonists with the potential to improve skin-aging phenotypes.

Oxidoreductases are effective biocatalysts, but their practical use is limited by the need for large quantities of NAD(P)H. In this study, a whole-cell biocatalyst for NAD(P)H cofactor regeneration was developed using the economical substrate glycerol. This cofactor regeneration system employs permeabilized Escherichia coli cells in which the glpD and gldA genes were deleted and the gpsA gene, which encodes NAD(P)+-dependent glycerol-3-phosphate dehydrogenase, was overexpressed. These manipulations were applied to block a side reaction (i.e., the conversion of glycerol to dihydroxyacetone) and to switch the glpD-encoding enzyme reaction to a gpsA-encoding enzyme reaction that generates both NADH and NADPH. We demonstrated the performance of the cofactor regeneration system using a lactate dehydrogenase reaction as a coupling reaction model. The developed biocatalyst involves an economical substrate, bifunctional regeneration of NAD(P)H, and simple reaction conditions as well as a stable environment for enzymes, and is thus applicable to a variety of oxidoreductase reactions requiring NAD(P)H regeneration.

Lilium bulbs have long been used as Chinese traditional medicines to alleviate the symptoms of various human inflammatory diseases. However, mechanisms of Lilium bulb-mediated anti-inflammatory activity and the bioactive components in Lilium bulbs remain unknown. In the present study, the anti-inflammatory activity of Lilium bulbs and the underlying mechanism of action were investigated in macrophages using Lilium bulb ethanol extracts (Lb-EE). In a dose-dependent manner, Lb-EE inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and bone marrow-derived macrophages (BMDMs) without causing significant cytotoxicity. Lb-EE also down-regulated mRNA expression of inflammatory genes in LPS-stimulated RAW264.7 cells, which included inducuble nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), and tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]). Furthermore, Lb-EE markedly restored LPS-induced morphological changes in RAW264.7 cells to a normal morphology. HPLC analysis identified quercetin, luteolin, and kaempferol as bioactive components contained in Lb-EE. Mechanistic studies in LPS-stimulated RAW264.7 cells revealed that Lb-EE suppressed MyD88- and TRIF-induced NF-[Formula: see text]B transcriptional activation and the nuclear translocation of NF-[Formula: see text]B transcription factors. Moreover, Lb-EE inhibited IKK[Formula: see text]/[Formula: see text]-induced activation of the NF-[Formula: see text]B signaling pathway and IKK inhibition significantly reduced NO production in LPS-stimulated RAW264.7 cells. Taken together, these results suggest that Lb-EE plays an anti-inflammatory role by targeting IKK[Formula: see text]/[Formula: see text]-mediated activation of the NF-[Formula: see text]B signaling pathway during macrophage-mediated inflammatory responses.

Background/Aims: Excessive melanogenesis often causes unaesthetic hyperpigmentation. In a previous report, our group introduced a newly synthesized depigmentary agent, Melasolv™ (3,4,5-trimethoxycinnamate thymol ester). In this study, we demonstrated the significant whitening efficacy of Melasolv using various melanocytes and human skin equivalents as in vitro experimental systems. Methods: The depigmentary effect of Melasolv was tested in melan-a cells (immortalized normal murine melanocytes), α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 murine melanoma cells, primary normal human melanocytes (NHMs), and human skin equivalent (MelanoDerm). The whitening efficacy of Melasolv was further demonstrated by photography, time-lapse microscopy, Fontana-Masson (F&M) staining, and 2-photon microscopy. Results: Melasolv significantly inhibited melanogenesis in the melan-a and α-MSH-stimulated B16 cells. In human systems, Melasolv also clearly showed a whitening effect in NHMs and human skin equivalent, reflecting a decrease in melanin content. F&M staining and 2-photon microscopy revealed that Melasolv suppressed melanin transfer into multiple epidermal layers from melanocytes as well as melanin synthesis in human skin equivalent. Conclusion: Our study showed that Melasolv clearly exerts a whitening effect on various melanocytes and human skin equivalent. These results suggest the possibility that Melasolv can be used as a depigmentary agent to treat pigmentary disorders as well as an active ingredient in cosmetics to increase whitening efficacy.

Ethnopharmacological relevance Seed of Torreya nucifera (L.) Siebold & Zucc is used to treat several diseases in Asia. Reports document that T. nucifera has anti-cancer, anti-inflammatory, anti-oxidative activities. In spite of numerous findings on its pharmacological effects, the understanding of the molecular inhibitory mechanisms of the plant remains to be studied. Therefore, we aimed to explore in vitro anti-inflammatory mechanisms of ethyl acetate fraction (Tn-EE-BF) prepared from the seed of T. nucifera in LPS-stimulated macrophage inflammatory responses. Materials and methods For this purpose, we measured nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated macrophages. Additionally, using RT-PCR, luciferase reporter gene assay, immunoblotting analysis, and kinase assay, the levels of inflammatory genes, transcription factors, and inflammatory signal-regulatory proteins were investigated. Finally, the constituent of Tn-EE-BF was identified using HPLC. Results Tn-EE-BF inhibits NO and PGE2 production and also blocks mRNA levels of inducible NO synthase (iNOS), tumor necrosis factor (TNF)-α, and cyclooxygenase (COX)-2 in a dose dependent manner. Tn-EE-BF reduces nuclear levels of the transcriptional factors NF-κB (p65) and AP-1 (c-Jun and FRA-1). Surprisingly, we found that Tn-EE-BF inhibits phosphorylation levels of Src and Syk in the NF-κB pathway, as well as, IRAK1 at the protein level, part of the AP-1 pathway. By kinase assay, we confirmed that Src, Syk, and IRAK1 are suppressed directly. HPLC analysis indicates that arctigenin, amentoflavone, and quercetin may be active components with anti-inflammatory activities. Conclusion Tn-EE-BF exhibits anti-inflammatory activities by direct inhibition of Src/Syk/NF-κB and IRAK1/AP-1.

Lilium bulbs have long been used as Chinese traditional medicines to alleviate the symptoms of various human inflammatory diseases. However, mechanisms of Lilium bulb-mediated anti-inflammatory activity and the bioactive components in Lilium bulbs remain unknown. In the present study, the anti-inflammatory activity of Lilium bulbs and the underlying mechanism of action were investigated in macrophages using Lilium bulb ethanol extracts (Lb-EE). In a dose-dependent manner, Lb-EE inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and bone marrow-derived macrophages (BMDMs) without causing significant cytotoxicity. Lb-EE also down-regulated mRNA expression of inflammatory genes in LPS-stimulated RAW264.7 cells, which included inducuble nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), and tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]). Furthermore, Lb-EE markedly restored LPS-induced morphological changes in RAW264.7 cells to a normal morphology. HPLC analysis identified quercetin, luteolin, and kaempferol as bioactive components contained in Lb-EE. Mechanistic studies in LPS-stimulated RAW264.7 cells revealed that Lb-EE suppressed MyD88- and TRIF-induced NF-[Formula: see text]B transcriptional activation and the nuclear translocation of NF-[Formula: see text]B transcription factors. Moreover, Lb-EE inhibited IKK[Formula: see text]/[Formula: see text]-induced activation of the NF-[Formula: see text]B signaling pathway and IKK inhibition significantly reduced NO production in LPS-stimulated RAW264.7 cells. Taken together, these results suggest that Lb-EE plays an anti-inflammatory role by targeting IKK[Formula: see text]/[Formula: see text]-mediated activation of the NF-[Formula: see text]B signaling pathway during macrophage-mediated inflammatory responses.

Abutilon crispum L. Medik, better known as bladdermallow, is used as a traditional remedy in India, for its anti-inflammatory effect due to its high content of flavonoids. However, research about its anti-inflammatory effect at the molecular level has not been performed. In this study, we aimed to investigate the mechanism of Abutilon crispum methanol extract (Ac-ME) in inhibiting the inflammatory response by conducting several experiments including cellular and molecular assays. Ac-ME inhibited the production of nitric oxide (NO) in RAW264.7 cells during treatment of LPS and Pam3CSK4 without exhibiting cytotoxicity. Ac-ME also suppressed the mRNA expression of inducible nitric oxide (iNOS) and proinflammatory cytokines such as interleukin (IL)-1β and IL-6. Moreover, Ac-ME was shown to inhibit the NF-κB pathway, according to the luciferase reporter gene assay performed with a NF-κB-Luc construct containing NF-κB-binding promoter regions under MyD88 and TRIF overexpression conditions, and immunoblotting analysis by determining the phospho-form levels of IκBα, IKKα/β, and p85, a regulatory domain of phosphatidylinositide 3-kinase (PI3K). Finally, we observed that the level of phospho-p85 induced by the overexpression of spleen tyrosine kinase (Syk) and Src was decreased by Ac-ME at 200 μg/ml. Therefore, these results suggest that Ac-ME has an anti-inflammatory effect by targeting PI3K in the NF-κB signaling pathway.

Oxidoreductases are effective biocatalysts, but their practical use is limited by the need for large quantities of NAD(P)H. In this study, a whole-cell biocatalyst for NAD(P)H cofactor regeneration was developed using the economical substrate glycerol. This cofactor regeneration system employs permeabilized

Abutilon crispum L. Medik, better known as bladdermallow, is used as a traditional remedy in India, for its anti-inflammatory effect due to its high content of flavonoids. However, research about its anti-inflammatory effect at the molecular level has not been performed. In this study, we aimed to investigate the mechanism of Abutilon crispum methanol extract (Ac-ME) in inhibiting the inflammatory response by conducting several experiments including cellular and molecular assays. Ac-ME inhibited the production of nitric oxide (NO) in RAW264.7 cells during treatment of LPS and Pam3CSK4 without exhibiting cytotoxicity. Ac-ME also suppressed the mRNA expression of inducible nitric oxide (iNOS) and proinflammatory cytokines such as interleukin (IL)-1β and IL-6. Moreover, Ac-ME was shown to inhibit the NF-κB pathway, according to the luciferase reporter gene assay performed with a NF-κB-Luc construct containing NF-κB-binding promoter regions under MyD88 and TRIF overexpression conditions, and immunoblotting analysis by determining the phospho-form levels of IκBα, IKKα/β, and p85, a regulatory domain of phosphatidylinositide 3-kinase (PI3K). Finally, we observed that the level of phospho-p85 induced by the overexpression of spleen tyrosine kinase (Syk) and Src was decreased by Ac-ME at 200 μg/ml. Therefore, these results suggest that Ac-ME has an anti-inflammatory effect by targeting PI3K in the NF-κB signaling pathway.

Tyrosinase 1 is a copper-containing enzyme which is widely distributed in nature. This enzyme is associated with the production of melanin for the protection of the skin from solar irradiation. However, overproduction of melanin in the skin is of particular concern to woman, for example, in the conditions melasma and lentigo. 2 Tyrosinase catalyzes the first two steps of melanin biosynthesis, namely the hydroxylation of L-tyrosine to L-dopa and the subsequent oxidation of L-dopa to dopaquinone. Tyrosinase is contained in vegetables and fruits and is responsible for the undesirable enzymatic browning that occurs upon long term storage of these. 3 Therefore, tyrosinase inhibitors have attracted attention as important depigmenting agents for the treatment of hyperpigmentation and as anti-browning agents in vegetables and fruits. Kojic acid 4 (1) is a well known tyrosinase inhibitor. However, its inhibitory activity is not potent enough for the above purposes. To overcome this drawback, many semisynthetic kojic acid derivatives have been synthesized, usually by modification of the C-2 hydroxyl group. 5 Recently, we synthesized kojic acid derivatives containing thioether 6 and ester 7 linkers and evaluated their tyrosinase inhibitory activities. Among them, 2-((cyclohexylthio)methyl)-5-hydroxy-4H-pyran-4-one (2b), showed the most potent inhibitory activity. Compound 2b is composed of three parts, including the kojic acid moiety, a thioether linker, and a hydrophobic cyclohexane group. We synthesized and evaluated additional compounds to get more structural insight into the tyrosinase inhibitory activity of the kojic acid derivatives. The crystallographic structure of tyrosinase has recently been established, enabling closer examination of its three-dimensional structure, which revealed the presence of a hydrophobic protein pocket adjoining the binuclear copper active site. 8 We also conducted a molecular docking study to elucidate the structural importance of the kojic acid derivatives in binding with the active site of tyrosinase. The synthetic pathways of the kojic acid derivatives are shown in Scheme 1. Thioether derivatives (2a-2e) were synthesized by the condensation of kojyl chloride 4 with the potassium salts of thiols. Ester derivatives (3a-3e) were synthesized by the condensation of kojyl chloride 4 with the potassium salts of acids. The inhibitory activities of the kojic acid derivatives on mushroom tyrosinase were investigated using kojic acid as a positive control. The results are summarized in Table 1.

E-mail: snpark@seoultech.ac.krReceived April 22, 2014, Accepted June 5, 2014Key Words : Dimeric cinnamoylamide, Melanin, Depigmentation, TyrosinaseHuman skin color is primarily determined by melaninproduction. Melanin is a biopigment synthesized by melano-cytes in a specialized cellular organelle called the melano-some.

The subcutaneous fat tissue mass gradually decreases with age, and its regulation is a strategy to develop anti-aging compounds to ameliorate the photo-aging of human skin. The adipogenesis of human adipose tissue-mesenchymal stem cells (hAT-MSCs) can be used as a model to discover novel anti-aging compounds. Cinnamomum cassia methanol extracts were identified as adipogenesis-promoting agents by natural product library screening. Cinnamates, the major chemical components of Cinnamomum cassia extracts, promoted adipogenesis in hAT-MSCs. We synthesized kojyl cinnamate ester derivatives to improve the pharmacological activity of cinnamates. Structure-activity studies of kojyl cinnamate derivatives showed that both the α,β-unsaturated carbonyl ester group and the kojic acid moiety play core roles in promoting adiponectin production during adipogenesis in hAT-MSCs. We conclude that kojyl cinnamate ester derivatives provide novel pharmacophores that can regulate adipogenesis in hAT-MSCs.

Seed oil triacylglycerol (TAG) composition of 32 soybean varieties were determined and compared using ¹H-NMR. The contents of linolenic (Ln), linoleic (L), and oleic (O) ranged from 10.7% to 19.3%, 37.4%-50.1%, and 15.7%-34.1%, respectively. As is evident, linoleic acid was the major fatty acid of soybean oil. Compositional differences among the varieties were observed. Natural oils containing unsaturated groups have been regarded as important nutrient and cosmetic ingredients because of their various biological activities. The TAG profiles of the soy bean oils could be useful for distinguishing the origin of seeds and controlling the quality of soybean oils. To the best of our knowledge, this is the first study in which the TAG composition of various soybean oils has been analyzed using the ¹H-NMR method.

E-mail: snpark@seoultech.ac.krReceived June 13, 2011, Accepted December 26, 2011Key Words : Depigmenting activity, Hydroxyl carboxamide, Hydrophobic moietySkin pigmentation results from an increase in either thenumber of melanocytes or the activity of tyrosinase, wherethe latter is responsible for melanin synthesis.

Tyrosinase 1 is widely distributed in microorganisms, animals, and plants and is responsible for melanization in animals and browning in plants. Melanin plays a crucial protective role against the photodamage of skin. However, the production of abnormal melanin pigmentation is a serious esthetic problem for human beings. In the food industry, tyrosinase is responsible for enzymatic browning reactions in damaged fruit during post-harvest handling and processing. Therefore, the development of tyrosinase inhibitors that can be used as skin whitening agents 2 or preservatives 3 for fresh food has been pursued. Kojic acid 4 (1) is produced by various fungi and bacteria and is widely used as a skin whitening agent because of its tyrosinase inhibitory activity. Kojic acid has also been shown to prevent photodamage due to its free radical scavenging activity. 5 However, its inhibitory activity and storage properties are insufficient for use in cosmetics and as an anti-browning agent for food. To increase its activity, many semi-synthetic kojic acid derivatives have been synthesized. Many of these compounds were formed by modifying the C-2 hydroxyl group to form esters, 6 ethers, 7 sulfides 8 and peptide 9 derivatives because C-5 enolic hydroxyl group is considered as a pharmacophore for tyrosinase inhibition. Recently, we synthesized a 2,4-dihydroxy benzoate ester of kojic acid containing an adamantane moiety (2) and evaluated its tyrosinase activity. 10 Although compound 2 has a kojic acid moiety for chelation to copper in the active site of tyrosinase, tyrosinase inhibitory activity is not found. We also synthesized a benzoate ester of kojic acid without an adamantane moiety and investigated its tyrosinase inhibitory and radical scavenging activities. Scheme 1 shows the synthetic pathways for the benzoate ester of kojic acid. The reaction of kojic acid with thionyl chloride produces compound 6, which is conveniently converted to compound 7 using dimethylsulfate and potassium carbonate in acetone under reflux conditions. Compounds 6 and 7, which are both chlorides, react with potassium salts of benzoic acids in dimethylformamide at 110 o C - 120 o C to give the corresponding ester derivatives 4a-4m and 5a-5c. First, we evaluated the tyrosinase inhibitory activities of the kojic acid and benzoate ester derivatives. Tyrosinase is known to be the enzyme responsible for the oxidation of tyrosine. The inhibitory activities were evaluated by measuring the transformation rate of L-tyrosine to L-dopaquinone. Compounds 4a-4m exhibited potent inhibitory activities against tyrosinase. The hydrophobic benzoate increased the inhibitory activity of kojic acid. However, the numbers and

A novel kojic acid derivative containing a trolox moiety, (±)-5-hydroxy-4-oxo-4H-pyran-2-yl methyl 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylate (3a), was synthesized. The two biologically active compounds, namely, kojic acid and trolox, were conjugated via an ester bond as they are expected to behave synergistically. The antioxidant activity and the tyrosinase inhibitory activity of this novel kojic acid derivative on melanogenesis were evaluated. Compound 3a exhibited potent tyrosinase inhibitory activity and radical scavenging activity. Limited structure–activity relationship (SAR) investigations indicated that the tyrosinase inhibitory activities may originate from the kojic acid moiety, and the radical scavenging activity may be due to the phenolic hydroxyl group of trolox. Compound 3a also exhibited potent depigmenting activity in a cell-based assay. The limited SAR investigations revealed that the depigmenting activity of 3a may be due to the synergistic activities of kojic acid and its trolox moiety.

ZYM-201 is a methyl ester of a novel triterpenoid glycoside. It is isolated from SANGUISORBA OFFICINALIS, a widely used medicinal plant in Korea, China, and Japan, that is prescribed for various diseases such as diarrhea, chronic intestinal infections, duodenal ulcers, and bleeding. In this study, the antihyperlipidemic effect of the salt form (sodium succinate) of ZYM-201 was examined using streptozotocin (STZ)-treated hyperglycemic rats. Oral administration of ZYM-201 sodium succinate (3 to 10 mg/kg) resulted in recovery of the increased serum levels of triglyceride (TG) and total cholesterol (TC) back to normal levels. Elevated levels of serum lipoproteins, such as high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL), were also significantly restored by this compound without altering 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase activity. Finally, ZYM-201 sodium succinate displayed antioxidative properties, including suppression of lipid peroxide and hydroxyl radical generation and upregulation of superoxide dismutase (SOD) activity. Therefore, our data strongly suggest that ZYM-201 sodium succinate can be used as a remedy for the treatment of diabetes-derived hyperlipidemic disorders such as atherosclerosis and vascular diseases.

Ginsenoside (G) Rp₁ is a ginseng saponin derivative with anti-cancer and anti-inflammatory activities. In this study, we examined the mechanism by which G-Rp₁ inhibits inflammatory responses of cells. We did this using a strategy in which DNA constructs containing cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) promoters were transfected into HEK293 cells. G-Rp₁ strongly inhibited the promoter activities of COX-2 and iNOS; it also inhibited lipopolysaccharide induced upregulation of COX-2 and iNOS mRNA levels in RAW264.7 cells. In HEK293 cells G-Rp₁ did not suppress TANK binding kinase 1-, Toll-interleukin-1 receptor-domain-containing adapter-inducing interferon-b (TRIF)-, TRIF-related adaptor molecule (TRAM)-, or activation of interferon regulatory factor (IRF)-3 and nuclear factor (NF)-κB by the myeloid differentiation primary response gene (MyD88)-induced. However, G-Rp₁ strongly suppressed NF-κB activation induced by Iκβ kinase (IKK)β in HEK293 cells. Consistent with these results, G-Rp₁ substantially inhibited IKKβ-induced phosphorylation of Iκβα and p65. These results suggest that G-Rp₁ is a novel anti-inflammatory ginsenoside analog that can be used to treat IKKβ/NF-κB-mediated inflammatory diseases.

Ginsenoside (G)-F1 is an enzymatic metabolite generated from G-Rg1. Although this metabolite has been reported to suppress platelet aggregation and to reduce gap junction-mediated intercellular communication, the modulatory activity of G-F1 on the functional role of skin-derived cells has not yet been elucidated. In this study, we evaluated the regulatory role of G-F1 on the cellular responses of B16 melanoma cells. G-F1 strongly suppressed the proliferation of B16 cells up to 60% at 200 μg/mL, while only diminishing the viability of HEK293 cells up to 30%. Furthermore, G-F1 remarkably induced morphological change and clustering of B16 melanoma cells. The melanin production of B16 cells was also significantly blocked by G-F1 up to 70%. Interestingly, intracellular signaling events involved in cell proliferation, migration, and morphological change were up-regulated at 1 h incubation but down-regulated at 12 h. Therefore, our results suggest that G-F1 can be applied as a novel anti?skin cancer drug with anti-proliferative and anti-migration features.

is involved in the pathogenesis of numerous diseases such as chronic inflammation, cancer, rheumatoid arth-ritis, and autoimmune diabetes. Macrophages play a pivotal role in inflammation by producing various mediators. One such primary inflammatory mediator, nitric oxide (NO), is produced enzymatically by inducible nitric oxide synthase (iNOS).

To find novel depigmenting agents, a new synthetic compound, N-adamantyl-3,4-dihydroxybenzamide (NADB) was produced and the effects on melanogenesis were investigated. Our results showed that NADB reduced melanin synthesis in a dose-dependent manner in melan-a cells. Tyrosinase activity was also reduced by NADB treatment in melan-a cells. However, NADB did not inhibit tyrosinase activity directly in a cell-free system. Treatment of melan-a cells with NADB caused a marked decrease in protein and mRNA levels of tyrosinase along with tyrosinase-related protein 1 and dopachrome tautomerase. To determine whether NADB reduces skin pigmentation, the dorsal skin of brown guinea pigs was shaved and irradiated with UV for 3 weeks using a solar simulator. Then NADB (2 or 1% in propylene glycol:ethanol:water = 5:3:2) was applied topically twice daily for 4 weeks. Visual inspection and Fontana-Masson staining both demonstrated that NADB resulted in lower skin pigmentation and total epidermal melanin in comparison to vehicle-treated areas. These findings suggest that NADB is useful in the treatment of hyperpigmentation.

) is well known depigmenting agent that is used to reduce melanin content by inhibition of tyrosinase. Although hydroquinone exhibits highly potent depigmenting activity, its application in cosmetics isrestricted because of its severe side effects such as melanocyte destruction, irritative dermatitis, and contact dermatitis. To over-come this disadvantage, its glycoside derivative, arbutin

is bifunctional enzyme, which catalyzes the hydroxylation of L-tyrosine to L-dopa and enhances the oxidation of L-dopa to dopaquinone. There-fore, inhibitors of tyrosinase should be useful as therapeutic agents for the treatment of melanin hyperpigmentation. Many metal ion chelators, for example, kojic acid

Data were obtained as meanvalue of 1/[V], inverse of the increase of optical density at 450 nm per min. (OD450/min), of three independent tests with differentconcentrations of L-tyrosine as a substrate. (A) with 100 μM (rectangle), 50 μM (triangle), 25 μM (circle), or no kojic acid (B) with 40 μM(rectangle), 20 μM (triangle), 10 μM (circle), or no compound

Lipid peroxidation has been suggested to play a key role in damaging biological processes resulting from excessive exposure to UV light. Aging of skin has been associated with increased peroxidation of skin lipid. In particular, squalene, which is a main component of skin surface polyunsaturated lipids, is easily peroxidized. Squalene-monohydroperoxide (Sq-OOH), the initial product of peroxidized squalene, is produced at the human skin by natural exposure to sunlight during day time activities. Recently, a few researchers reported on the damages of hairless mice skin by the topical application of Sq-OOH. Repeated application of Sq-OOH to the hairless mice induced its the skin wrinkles with clear and fine appearance. Histologically were seen, more keratinocyte hypertrophy with Sq-OOH treated skin than with chronic UVB irradiated group in epidermis. In dermis, characteristics, found in UVB irradiated skin, such as the loss of polarity, fractured collagen bundle and elastosis, were not observed severely. The alteration of epidermal layer might be the main factor for the formation of wrinkle caused by Sq-OOH. From the previous works, Sq-OOH is considered as an important source of damage in the early stage of aging process to result in epidermal wrinkle. Thus, it is very important to minimize such damage that would be induced mainly by Sq-OOH against healthy skin condition. Therefore, we tried to develop new anti-aging materials for protecting skin damage by Sq-OOH. Hydroxamic acids, the naturally occurring products exhibit low toxicities in general, and are of interest for many therapeutic applications. Recently, hydroxamic acids and derivatives were reported largely as effective antibacterial and antifungal agents. Their activities originate from their ability to coordinate on metal ions. That is, hydroxamic acid group is regarded as an one electron donor. Hydroxamic acid moiety has also drawn much attention as a reactive oxygen species (ROS) scavenger. In this study, a new skin protecting compound, (4-(Nhydroxycarbamoyl)phenyl)-N-adamantanylcarboxamide (1) is synthesized to show inhibitory activities of lipid peroxidation both in vitro and in vivo. The targeted compound 1 is a hydroxamic acid derivative which possesses an amide linker between hydroxamic acid and adamantane moiety. Adamantane group was adopted as a hydrophobic moiety to optimize antioxidant activity of hydroxamic acid in animal test. Compound 1 is believed to be adequate in skin permeation because of its balance in hydrophilic and hydrophobic character.

Two kaempferol glycosides were isolated from green tea seed extract (GTSE). After conducting a structure analysis, these two compounds were identified as kaempferol-3-O-[2-O-beta-D-galactopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 1) and kaempferol-3-O-[2-O-beta-D-xylopyranosyl-6-O-alpha-L-rhanmopyranosyl]-beta-D-glucopyranoside (compound 2). These two compounds were hydrolysed by o-glycolytic enzymes for the production of kaempferol. After performing several reactions, we found the optimum enzyme combination, a reaction with beta-galactosidase and hesperidinase. Finally, we produced kaempferol of above 95% purity. The 5alpha-reductase inhibition activities of GTSE hydrolysate (GTSE-H) containing kaempferol were evaluated by the contact cell-based metabolic method using a stable HEK 293 cell line. GTSE-H showed a good inhibition effect on HEK 293 cell lines both type 1 and type 2 on 5alpha-reductase. Especially, GTSE-H inhibited type 2 with kaempferol content dependency. The results indicate that the inhibition activity of hydrolysate on 5alpha-reductase type 2 increases in accordance with kaempferol content.

Background Although retinoids have potential efficacy in aged skin, their side effect (skin irritation) remains a clinical problem. We designed a novel synthetic retinoid, seletinoid G, by using computer-aided molecular modeling, and investigated its effects on the expression of extracellular matrix proteins in human skin in vivo. Methods Twenty-three subjects were tested on the buttocks using 4-day occlusive application of seletinoid G and all- trans retinoic acid ( t RA). Skin irritation after topical application was quantified by the degree of erythema and cutaneous blood flow. The expression of extracellular matrix proteins and interstitial collagenase (MMP-1) in skin biopsies was investigated by immunohistochemical staining and Western blotting. Results The topical application of seletinoid G under occlusion induced no skin irritation in contrast to t RA, which caused severe erythema. The topical treatment with seletinoid G increased the expressions of type I procollagen, tropoelastin, and fibrillin-1, and reduced MMP-1 in old skin in vivo. Seletinoid G was found to inhibit not only the UV-induced decrease of type I procollagen but the UV-induced increase of MMP-1 and c-Jun protein in young skin in vivo. Conclusions Seletinoid G is a novel synthetic retinoid, which has little the side effect of skin irritation after topical application. Seletinoid G can repair altered connective tissue in old skin and inhibit UV-induced collagen deficiency in young skin.

Π-A isotherms and phase behaviors of ‘tocomide’, a newly synthesized 1,3-bis(N-(2-hydroxyethyl)-tocopherol succinylamino)-2-hydroxypropane, mixed with cholesterol and linoleic acid, was studied for its monolayer miscibility and a stable delivery formulation for antioxidant applications. The monolayer of tocomide and cholesterol was formed in a homogeneously mixed state at air–water interface. The ternary mixtures with linoleic acid showed various bulk structures, including a stable and transparent solution of thermodynamically stable lamellar phase. The lamellar structure was confirmed by the X-ray diffraction (XRD) patterns and polarized microscopy such that pure tocomide formed a liquid crystal at room temperature with a lamellar periodicity of 36.7 A (2θ=2.41°)

Various 3-halo flavones were prepared by reaction of the corresponding flavone derivatives with R4NBr/PhI(OAc)2 system under mild reaction conditions.

21-O-Angeloyltheasapogenol E3 (ATS-E3) is a triterpenoid saponin recently isolated from the seeds of the tea treeCamellia sinensis(L.) O. Kuntze. ATS-E3 has several beneficial properties including anti-inflammatory, antidiabetic, antiatherosclerotic, and anticancer effects. Unlike other phenolic compounds isolated from tea plants, there are no studies reporting the pharmacological action of ATS-E3. In this study, we therefore aimed to explore the cellular and molecular inhibitory activities of ATS-E3 in macrophage-mediated inflammatory responses. ATS-E3 remarkably diminished cellular responses of macrophages such as FITC-dextran-induced phagocytic uptake, sodium nitroprusside- (SNP-) induced radical generation, and LPS-induced nitric oxide (NO) production. Analysis of its molecular activity showed that this compound significantly suppressed the expression of inducible NO synthase (iNOS), nuclear translocation of nuclear factor- (NF-)κB subunits (p50 and p65), phosphorylation of inhibitor ofκB kinase (IKK), and the enzyme activity of AKT1. Taken together, the novel triterpenoid saponin compound ATS-E3 contributes to the beneficial effects of tea plants by exerting anti-inflammatory and antioxidative activities in an AKT/IKK/NF-κB-dependent manner.

In this study, we aimed to examine the cellular and molecular mechanisms of lancemaside A fromCodonopsis lanceolata(Campanulaceae) in the inflammatory responses of monocytes (U937 cells) and macrophages (RAW264.7 cells). Lancemaside A significantly suppressed the inflammatory functions of lipopolysaccharide- (LPS-) treated RAW264.7 cells by suppressing the production of nitric oxide (NO), the expression of the NO-producing enzyme inducible NO synthase (iNOS), the upregulation of the costimulatory molecule CD80, and the morphological changes induced by LPS exposure. In addition, lancemaside A diminished the phagocytic activity of RAW264.7 cells and boosted the neutralizing capacity of these cells when treated with the radical generator sodium nitroprusside (SNP). Interestingly, lancemaside A strongly blocked the adhesion activity of RAW264.7 cells to plastic culture plates, inhibited the cell-cell and cell-fibronectin (FN) adhesion of U937 cells that was triggered by treatment with an anti-β1-integrin (CD29) antibody and immobilized FN, respectively. By evaluating the activation of various intracellular signaling pathways and the levels of related nuclear transcription factors, lancemaside A was found to block the activation of inhibitor ofκB kinase (IKK) and p65/nuclear factor- (NF-)κB. Taken together, our findings strongly suggest that the anti-inflammatory function of lancemaside A is the result of its strong antioxidative and IKK/NF-κB inhibitory activities.

The cyclic thionocarbonates of aromatic 2,3-dihydroxy esters, which have an electron-withdrawing group, undergo deoxygenation with magnesium in methanol to form α-keto esters or α-hydroxy esters, depending on the type of electron-withdrawing group.

Various 3-haloflavones were prepared by the reaction of the corresponding flavone derivatives with iodobenzene diacetate and trimethylsilyl halide under mild reaction conditions. The iodobenzene diacetate could be replaced by the polymer supported iodobenzene diacetate without the decreasing activity. See Reference [1a], [1b], [1c], [1d], [1e], [1f], [1g].

This study was conducted to examine the tyrosinase inhibitory and anti-inflammatory activities of kojic acid derivatives. A series of kojic acid derivatives containing thioether, sulfoxide, and sulfone linkages were synthesized. In the tyrosinase assay, kojyl thioether derivatives containing appropriate lipophilic alkyl chains (pentane, hexane, and cyclohexane) showed potent inhibitory activity. However, sulfoxides and sulfones exhibited decreased activity. Similar experimental results were obtained with inhibitory activities of NO production being induced by LPS. The presence of thioether linkage and appropriated lipophilic acid moiety was critical for the tyrosinase inhibitory and anti-inflammatory activities.

Deoxygenation of the cyclic thionocarbonates of 2,3-dihydroxy esters was mediated with magnesium in methanol, which provided a facile method for the synthesis of α-hydroxy esters

Tyrosinase is a copper-containing enzyme, which catalyzes two distinct reactions of melanin synthesis, the hydroxylation of L-tyrosine to L-dopa and the oxidation of L-dopa to dopaquinone. These processes are involved in local hyperpigmentation such as melasma and lentigo. Therefore, the inhibition of tyrosinase to treat the pigmentation disorders has been a recent subject of many studies. Kojic acid (1) is well known as one of the most popular tyrosinase inhibitors and it has been widely used as a skin-whitening agent. However, the inhibitory activity of kojic acid is not potent enough. To overcome this drawback, many semi-synthetic kojic acid derivatives were synthesized usually by the modification of C-2 hydroxyl group into ester, hydroxyphenyl ether, and glycoside. Recently, two molecules of kojic acid were connected by ester and ethylene. Their inhibitory activities were dramatically enhanced. Thus we became interested in new kojic acid derivatives containing two molecules of kojic acid. In this study, we connected two molecules of kojic acid by various chemical bonds such as ester, amide, and thioether. Anti-melanogenic activities of compounds (4a-4f) were compared with that of kojic acid (Figure 1).