Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10.

Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 µM (PM10). PM10 stimulates the production of reactive oxygen species (ROS) and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE) on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and monocyte chemoattractant protein-1 (MCP-1), and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). PPE at 10-100 µg mL(-1) attenuated the production of ROS and the expression of TNF-α, IL-1ß, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 µg mL(-1)). PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter.

Anti-melanogenic effects of resveratryl triglycolate, a novel hybrid compound derived by esterification of resveratrol with glycolic acid.

Resveratrol is known to inhibit cellular melanin synthesis by multiple mechanisms. Glycolic acid (GA) is used in skin care products for its excellent skin penetration. The purpose of this study was to examine the anti-melanogenic effects of resveratryl triglycolate (RTG), a novel hybrid compound of resveratrol and GA, in comparison with resveratrol, GA, resveratryl triacetate (RTA) and arbutin. Resveratrol, RTG, and RTA inhibited the catalytic activity human tyrosinase (TYR) more potently than arbutin or GA did. Their cytotoxic and anti-melanogenic effects were examined using murine melanoma B16/F10 cells and human epidermal melanocytes (HEMs). The cytotoxicity of RTG was similar to that of resveratrol and RTA. RTG at 3-10 µM decreased melanin levels and cellular TYR activities in α-melanocyte-stimulating hormone-stimulated B16/F10 cells, and L-tyrosine-stimulated HEMs. RTG also suppressed mRNA and protein expression of TYR, tyrosinase-related protein 1, L-3,4-dihydroxyphenylalanine chrome tautomerase, and microphthalmia-associated transcription factor (MITF) in HEMs stimulated with L-tyrosine. This study suggests that, like resveratrol and RTA, RTG can attenuate cellular melanin synthesis effectively through the suppression of MITF-dependent expression of melanogenic enzymes and the inhibition of catalytic activity of TYR enzyme. RTG therefore has potential for use as a cosmeceutical ingredient for skin whitening.

Scutellaria radix Extract as a Natural UV Protectant for Human Skin.

Ultraviolet (UV) radiation induces oxidative injury and inflammation in human skin. Scutellaria radix (SR, the root of Scutellaria baicalensis Georgi) contains flavonoids with high UV absorptivity and antioxidant properties. The purpose of this study was to examine the potential use of SR extract as an additive in cosmetic products for UV protection. SR extract and its butanol (BuOH) fraction strongly absorbed UV radiation and displayed free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radials and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals. They also attenuated the UV-induced death of HaCaT cells. Sunscreen creams, with or without supplementation of SR extract BuOH fraction, were tested in vivo in human trials to evaluate potential skin irritation and determine the sun protection factor (SPF). Both sunscreen creams induced no skin irritation. A sunscreen cream containing 24% ZnO showed an SPF value of 17.8, and it increased to 22.7 when supplemented with 5% SR extract BuOH fraction. This study suggests that SR-derived materials are useful as safe cosmetic additives that provide UV protection.

Suppression of 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis by glyceollins.

SCOPE: Our previous study showed that glyceollins induced phase 2 detoxifying and antioxidant enzymes. As chemical carcinogens can be detoxified by metabolic activity of phase 2 enzymes, subsequently decreasing their tumorigenic potential, we investigated whether 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumorigenesis could be attenuated by treatment with glyceollins in a mouse model. METHODS AND RESULTS: Pretreatment with glyceollins (5 mg/kg body weight) caused a significant reduction in tumor formation and an increase in survival rate. The protective effect of glyceollins against DMBA-induced tumorigenesis was found to be mainly associated with their potential to induce phase 2/antioxidant enzymes that are, in turn, regulated by the nuclear factor E2-related factor 2 signaling pathway, and to a less extent to suppress phase 1 enzymes. As glyceollins increased the number of terminal end buds, a tumor-prone mammary tissue type in mice, it is unlikely that they exert their antitumorigenic action through their estrogenic activity. CONCLUSION: Glyceollins were found to have a protective effect in a chemically induced mammary tumor model.

Photovoltaic performance of TiO2 electrode adsorbed with gardenia yellow purified by nonionic polymeric sorbent in dye-sensitized solar cells.

To improve the photovoltaic conversion efficiency in dye-sensitized solar cells (DSSCs), TiO2 electrode adsorbed with gardenia yellow purified by nonionic polymeric sorbent was successfully formulated on nanoporous TiO2 surface. Adsorption and desorption properties of crude gardenia yellow solution on a macroporous resin, XAD-1600, were investigated to purify gardenia yellow because of its strong adsorption and desorption abilities as well as high selectivity. To this end, adsorption equilibrium and kinetic data were measured and fitted using adsorption isotherms and kinetic models. Adsorption and desorption breakthrough curves in a column packed with XAD-1600 resin was obtained to optimize the separation process of gardenia yellow. The photovoltaic performance of the photo-electrode adsorbed with the crude and purified gardenia yellow in DSSCs was compared from current-voltage measurements. The results showed that the photovoltaic conversion efficiency was highly dependent on how to separate and purify gardenia yellow as a photosensitizer.

Gardenia jasminoides Extract Attenuates the UVB-Induced Expressions of Cytokines in Keratinocytes and Indirectly Inhibits Matrix Metalloproteinase-1 Expression in Human Dermal Fibroblasts.

Ultraviolet radiation (UV) is a major cause of photoaging, which also involves inflammatory cytokines and matrix metalloproteinases (MMP). The present study was undertaken to examine the UVB-protecting effects of yellow-colored plant extracts in cell-based assays. HaCaT keratinocytes were exposed to UVB in the absence or presence of plant extracts, and resulting changes in cell viability and inflammatory cytokine expression were measured. Of the plant extracts tested, Gardenia jasminoides extract showed the lowest cytotoxicity and dose-dependently enhanced the viabilities of UVB-exposed cells. Gardenia jasminoides extract also attenuated the mRNA expressions of interleukin-1 ß (IL-1 ß ) and tumor necrosis factor- α (TNF- α ) in HaCaT cells stimulated by UVB. Conditioned medium from UVB-exposed HaCaT cells was observed to stimulate MMP-1 protein expression in human dermal fibroblasts, and this effect was much smaller for the conditioned medium of HaCaT cells exposed to UVB in the presence of Gardenia jasminoides extract. Gardenia jasminoides extract also exhibited antioxidative and antiapoptotic effects in HaCaT cells exposed to UVB. These results indicated that UVB-induced injury and inflammatory responses of skin cells can be attenuated by yellow-colored plant extracts, such as Gardenia jasminoides extract.

Effects of resveratrol, oxyresveratrol, and their acetylated derivatives on cellular melanogenesis.

Resveratrol and oxyresveratrol are naturally occurring phenolic compounds with various bioactivities, but their uses in cosmetics have been partly limited by their chemical instabilities. This study was performed to examine the anti-melanogenic effects of the acetylated derivatives from resveratrol and oxyresveratrol. Resveratrol and oxyresveratrol were chemically modified to triacetyl resveratrol and tetraacetyl oxyresveratrol, respectively. The acetylated compounds were less susceptible than the parent compounds to oxidative discoloration. The acetylated compounds inhibited the activities of tyrosinases less than parent compounds in vitro, but they were as effective at cellular melanogenesis inhibition, indicating bioconversion to parent compounds inside cells. Supporting this notion, the parent compounds were regenerated when the acetylated compounds were digested with cell lysates. Although resveratrol and triacetyl resveratrol inhibited tyrosinase activity less effectively than oxyresveratrol and tetraacetyl oxyresveratrol in vitro, they inhibited cellular melanogenesis more effectively. This discrepancy was explained by strong inhibition of tyrosinase expression by resveratrol and triacetyl resveratrol. Experiments using a reconstituted skin model indicated that resveratrol derivatives can affect melanin synthesis and cell viability to different extents. Collectively, this study suggests that acetylated derivatives of resveratrol have great potential as anti-melanogenic agents for cosmetic use in terms of efficacy, safety, and stability.

Antioxidant activities of licorice-derived prenylflavonoids.

Glycyrrhiza uralensis (or licorice) is a widely used Oriental herbal medicine from which the phenylflavonoids dehydroglyasperin C (DGC), dehydroglyasperin D (DGD), and isoangustone A (IsoA) are derived. The purpose of the present study was to evaluate the antioxidant properties of DGC, DGD, and IsoA. The three compounds showed strong ferric reducing activities and effectively scavenged DPPH, ABTS(+), and singlet oxygen radicals. Among the three compounds tested, DGC showed the highest free radical scavenging capacity in human hepatoma HepG2 cells as assessed by oxidant-sensitive fluorescent dyes dichlorofluorescein diacetate and dihydroethidium bromide. In addition, all three compounds effectively suppressed lipid peroxidation in rat tissues as well as H(2)O(2)-induced ROS production in hepatoma cells. This study demonstrates that among the three phenylflavonoids isolated from licorice, DGC possesses the most potent antioxidant activity, suggesting it has protective effects against chronic diseases caused by reactive oxygen species as well as potential as an antioxidant food additive.

Antioxidant activity of aqueous methanol extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages.

In this study, we evaluate the antioxidant properties of the various extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages. The antioxidant activities of six different extracts from larvae, pupae and imago were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and singlet oxygen (¹O2 ). The larval methanol extracts (LME) and imago methanol extracts (IME) displayed the greatest effect in DPPH and ABTS radical scavenging assay, but the activity of water extracts was weaker in the all tested assays. However, LME and IME could be compared to ascorbic acid in ¹O2 quenching ability (the effective concentrations of 50% ¹O2 quenching: EC50 0.174, 0.149 and 0.177 mg mL⁻¹, respectively). The antioxidant ability of the extracts to scavenge free radicals could significantly change the contents of gallic acid equivalent, an important factor based on the value of R². The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce oxidative stress as well as play a vital role in protecting insect organisms against oxidative damage caused by undesirable conditions.

Determination of singlet oxygen quenching and protection of biological systems by various extracts from seed of Rumex crispus L.

The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect and total phenolic contents were evaluated for the screening of singlet oxygen ((1)O(2)) quenching efficacy of various seed extracts from Rumex crispus L. The butanol and ethyl-acetate extracts displayed remarkable effect of DPPH as compared to positive control ascorbic acid. The concentrations (QC(50)) of butanol and ethyl-acetate extracts required to exert 50% reducing effect on (1)O(2) were found to be 116 and 82 µg mL(-1), respectively. Both extracts were also found to protect the in vitro biological system from the detrimental effect of (1)O(2) on type II photosensitization in Escherichia coli, red blood cell, lactate dehydrogenase and histidine. Among all the tested extracts, the ethyl-acetate and butanol extracts contained higher amount of total phenolic contents. The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce photo-produced oxidative stress involving reactive oxygen species in living organisms.

Antioxidant activity of glyceollins derived from soybean elicited with Aspergillus sojae.

The extract of soybean exposed to biotic elicitors such as food-grade fungus is known to have antioxidant activity. Glyceollins were major bioactive compounds present in soybean elicited by fungi and shown to have antifungal and anticancer activities. The purpose of present study was to evaluate the antioxidant activities of glyceollins by measuring ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, singlet oxygen quenching, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, hydroxyl radical scavenging activity, and lipid peroxidation inhibition. In addition, the antioxidant potential of glyceollins were measured by a fluorescent probe, 2',7'-dichlorofluorescin diacetate (DCFDA), and dihydroethidium (DHE) in mouse hepatoma hepa1c1c7 cells in which they were insulted with H2O2 to generate reactive oxygen species (ROS). Glyceollins showed a strong reducing power and inhibited lipid peroxidation, with significant scavenging activities of radicals including singlet oxygen, superoxide anion, ABTS, and DPPH. We also found that glyceollins significantly suppressed H2O2-induced ROS production in hepa1c1c7 cells. Therefore, glyceollins deserve further study as natural antioxidants and nutraceuticals.

Antifungal activity of glyceollins isolated from soybean elicited with Aspergillus sojae.

The aim of this study was to examine the efficacy of glyceollins isolated from soybean seeds elicited with Aspergillus sojae for its antifungal potential. Glyceollins I, II, and III were determined by HPLC-MS analysis. The glyceollins (200 and 600 microg/disk) revealed remarkable antifungal effect against Fusarium oxysporum , Phytophthora capsici, Sclerotinia sclerotiorum, and Botrytis cinerea, within the growth inhibition range of 10.9-61.0%, along with their respective MIC values ranging from 25 to 750 microg/mL. The glyceollins also had a strong detrimental effect on spore germination of all tested plant pathogens along with concentration- as well as time-dependent kinetic inhibition of P. capsici. Thus, the results obtained in this study demonstrate that glyceollins derived from soybean seeds elicited with A. sojae possess a wide range of fungicidal activity and could become an alternative to synthetic fungicides for controlling certain important fungal diseases.

Estrogenic activity of glyceollins isolated from soybean elicited with Aspergillus sojae.

Glyceollins, which are synthesized from daidzein in soybeans cultured with fungi, have been shown to have antifungal effects and cancer preventive properties. Several studies have proposed that isoflavones and their metabolites act as a mixed agonist/antagonist for estrogen. Although glyceollins were reported to suppress some cancer cells via anti-estrogenic activity, it is not clear whether the compounds possess estrogenic potential. In contrast to the anti-estrogenic action reported thus far, we observed estrogenic effects of glyceollins using E-screen assay and pS2 expression, whereas glyceollins showed higher affinity for estrogen receptor (ER) beta than ERalpha. We also found that glyceollins were more efficiently produced de novo in minced than in half-sliced soybean, following infection with Aspergillus sojae. In conclusion, glyceollins may be useful in the prevention or amelioration of postmenopausal complications because they had strong estrogenic activity, and their production could be variable depending upon processing prior to fungal inoculation.

Antioxidant activity of various solvent extracts from Allomyrina dichotoma (Arthropoda: Insecta) larvae.

This study was under taken to evaluate the antioxidant properties of larvae extracts of Allomyrina dichotoma. The antioxidant activities of various larvae extracts of water, methanol, ethyl-acetate, chloroform, and hexane were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide anion radical and singlet oxygen ((1)O(2)). The methanolic larvae extracts displayed the greatest effect in DPPH radical scavenging assay, but the reducing activity of larvae extracts was weaker in the superoxide anion radical assay. However, methanol (ME) and chloroform extracts (CE) could be compared to ascorbic acid in (1)O(2) quenching ability. ME (the concentration of 50% (1)O(2) quenching, QC(50)=0.080mg/ml) and CE (QC(50)=0.051mg/ml) extracts had 1.7, 2.7 times better efficiency than ascorbic acid (QC(50)=0.138mg/ml), respectively. Also the extracts were found to protect biological systems in Escherichia coli and lactate dehydrogenase against detrimental effects of (1)O(2) of type II photosensitization in vitro. The ability of larvae extracts to scavenge free radicals could significantly change contents of GA equivalent, an important factor for the potency of antioxidant capacity. The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce oxidative stress in living organisms involving reactive oxygen species as well as play a vital role in insect organisms against oxidative damage of undesirable conditions.

Characterization and cDNA cloning of a cecropin-like antimicrobial peptide, papiliocin, from the swallowtail butterfly, Papilio xuthus.

Cecropin is a well-studied antimicrobial peptide that is synthesized in fat body cells and hemocytes of insects in response to hypodermic injury or bacterial infection. A 503 bp cDNA encoding for a cecropin-like peptide was isolated by employing annealing control primer (ACP)-based differential display PCR and 5'-RACE with immunized Papilio xuthus larvae. The open reading frame of the isolated cDNA encoded for a 62-amino acid prepropeptide with a putative 22-residue signal peptide, a 2-residue propeptide, and a 38-residue mature peptide with a theoretical mass of 4060.89 Da. The deduced amino acid sequence of the peptide evidenced a significant degree of identity with other lepidopteran cecropins. This peptide was named papiliocin. RTPCR results revealed that the papiliocin transcript was detected at significant levels after injection with bacterial lipopolysaccharide (LPS). On the basis of the deduced amino acid sequence of papiliocin, a 38-mer mature peptide was chemically synthesized via the Fmoc method, and its antimicrobial activity was analyzed. The synthetic papiliocin peptide evidenced a broad spectrum of activity against fungi, Gram-positive and Gram-negative bacteria, and also evidenced no hemolytic activity against human red blood cells.

Isolation and Characterization of a Defensin-Like Peptide (Coprisin) from the Dung Beetle, Copris tripartitus.

The antibacterial activity of immune-related peptides, identified by a differential gene expression analysis, was investigated to suggest novel antibacterial peptides. A cDNA encoding a defensin-like peptide, Coprisin, was isolated from bacteria-immunized dung beetle, Copris tripartitus, by using differential dot blot hybridization. Northern blot analysis showed that Coprisin mRNA was up-regulated from 4 hours after bacteria injection and its expression level was reached a peak at 16 hours. The deduced amino acid sequence of Coprisin was composed of 80 amino acids with a predicted molecular weight of 8.6 kDa and a pI of 8.7. The amino acid sequence of mature Coprisin was found to be 79.1% and 67.4% identical to those of defensin-like peptides of Anomala cuprea and Allomyrina dichotoma, respectively. We also investigated active sequences of Coprisin by using amino acid modification. The result showed that the 9-mer peptide, LLCIALRKK-NH(2), exhibited potent antibacterial activities against Escherichia coli and Staphylococcus aureus.

Quality control of photosystem II under light stress - turnover of aggregates of the D1 protein in vivo.

When photodamaged under excessive light, the D1 protein is digested and removed from Photosystem (PS) II to facilitate turnover of the protein. In vitro studies have shown that part of the photodamaged D1 protein forms aggregates with surrounding polypeptides before being digested by a protease(s) in the stroma [Yamamoto Y (2001) Plant Cell Physiol 42: 121-128]. The aim of this study was to examine whether light-induced aggregation of the D1 protein also occurs in vivo. The following results were obtained: (1) PS II activity in spinach leaves was significantly inhibited by weak illumination (light intensity, 20-100 microE m-2 s-1), as monitored by chlorophyll fluorescence Fv/Fm, when the leaves were kept at higher temperatures (35-40 degrees C); (2) aggregation of the D1 protein, as well as cleavage of the protein, was detected in thylakoids isolated from spinach leaves that had been subjected to heat/light stress; (3) aggregates of the D1 protein disappeared after incubation of the leaves at 25 degrees C in the dark or under illumination with weak light. Since it is dependent on the presence of oxygen, aggregation of the D1 protein is probably induced by reactive oxygen species produced in thylakoids upon illumination at elevated temperatures. Consistent with this notion, singlet oxygen production in thylakoid samples under illumination was shown to be stimulated significantly at higher temperatures.

Spontaneous generation of reactive oxygen species in the mixture of cyanide and glycerol.

Reactive oxygen species are involved in tumor promotion or apoptosis. In assaying prooxidant or antioxidant activities, cyanide has been commonly used as an inhibitor of mitochondrial oxidases, peroxidases, or Cu,Zn-superoxide dismutase, which have an influence on intracellular levels of reactive oxygen species. It has also been used to chemically mimic hypoxia. On the other hand, glycerol has been widely used as a stabilizer of various enzymes. In particular, glycerol is required to maintain the enzymatic activities of membrane-bound NAD(P)H oxidases extracted from surrounding phospholipids. Since both cyanide and glycerol are relatively inert, they have been used concomitantly regardless of any mutual interference. In this study, we demonstrate that a mixture of glycerol and cyanide reduced cytochrome c and nitroblue tetrazolium, both of which are superoxide anion indicators. The mixture also enhanced the production of superoxide anion in the presence of redox-cycling compounds. Superoxide production by the mixture was confirmed by electron spin resonance spectra. Moreover, the mixture induced lipid peroxidation and hemolysis in human erythrocytes. These results suggest that cyanide and glycerol should be used carefully in reaction systems used to measure superoxide production or antioxidant activity. However, sucrose and sodium azide in combination do not produce such artifacts and thus may be used as an alternative.

Mycosporine glycine protects biological systems against photodynamic damage by quenching singlet oxygen with a high efficiency.

This report concerns physiological function of mycosporine-like amino acids (MAA) as an active defense against the photooxidative effects of sunlight in marine organisms. Mycosporine glycine (MG) is a representative member of MAA family and was found to effectively suppress various detrimental effects of the Type-II photosensitization in biological systems, such as inactivation of mitochondrial electron transport, lipid peroxidation of microsomes, hemolysis of erythrocytes and growth inhibition of Escherichia coli. The presence of MG in solutions of eosin Y or methylene blue resulted in a marked decrease in the level of singlet oxygen (1O2) produced by the sensitizers under illumination. The rate constant of 1O2 quenching by MG was determined to be 5.6 x 10(7) M(-1) s(-1) by the time-resolved 1O2 luminescence decay method, which is higher than, or at least comparable to, the values for 1O2 reaction of well-known quenchers such as 1,4-diazabicyclo[2,2,2]octane and furfuryl alcohol. The results suggest that MG probably together with some other active MAA may play an important role in protecting marine organisms against sunlight damage by eliminating 1O2 generated from certain endogenous photosensitizers.

Photodynamic effect of iron excess on photosystem II function in pea plants.

An earlier mechanistic phase of iron toxicity in photosynthetic cells was interpreted in terms of enhanced photodynamic action by the cytochrome b6/f complex (Cyt b6/f) via singlet oxygen (1O2) on the photosystem II complex (PS II). Iron excess was induced in hydroponically cultured pea (Pisum sativum L.) plants, and its effect on the function of PS II in vivo as well as in vitro was studied under high-irradiance conditions. Iron excess in plants gave rise to a significant increase in Cyt b6/f content of thylakoids. It appeared that the larger the content of Cyt b6/f, the more susceptible PS II was to photoinhibition, and the higher the rate of 1O2 photoproduction in thylakoids was. The action spectrum for degradation of the D1 protein in thylakoids revealed that photosensitization by nonporphyrin chromophore(s) was apparently associated with near UV to blue light-induced deterioration of PS II. The results are pertinent to the concept that photooxidative damage to PS 11, exacerbated by iron accumulation in thylakoid membranes in the form of Cyt b6/f, is involved in the mechanism of iron toxicity in leaf cells.