Article

Elastase, tyrosinase and lipoxygenase inhibition and antioxidant activity of an aqueous extract from Epilobium angustifolium L. leaves

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Abstract

Herbs have been utilized to treat acute and chronic disorders since thousand years. Epilobium angustifolium L. (Onagraceae) is used as herbal and digestive plant all over the world. The Epilobium extracts are reported to have analgesic, anti-microbial, antimotility, antiproliferative, antiinflammatory, antitumor and antiandrogenic activities. In the present study, the antioxidant activity and elastase, tyrosinase, lipoxygenase inhibitor capacity of E. angustifolium L. were examined. Total phenolic and total flavonoid content, reducing power, superoxide anion radical scavenging, hydroxyl radical scavenging, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities were used to evaluate the antioxidant activities. The results were compared with natural and synthetic antioxidants. The aqueous extract of E. angustifolium exhibited strong elastase (EC 50 = 42.72  2.38 g/ml), tyrosinase (EC 50 = 33.03  3.71 g/ml) and lipoxygenase inhibitory activities (EC 50 = 0.57  0.06 g/ml). The extract also showed good antioxidant activity in all antioxidant tests. According to these results, E. angustifolium may be considered as an important source for pharmaceutical, cosmetic and food manufactures due to its elastase, tyrosinase, lipoxygenase inhibitory activities and antioxidant activities.

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... The increasing application of plant antioxidants could replace the application of synthetic antioxidants [32,41,42]. Natural antioxidants can be a single pure compound/isolate, a mixture of compounds, or plant extracts; these antioxidants are now widely used in cosmetic products [39]. ...
... Natural antioxidants can be a single pure compound/isolate, a mixture of compounds, or plant extracts; these antioxidants are now widely used in cosmetic products [39]. Natural antioxidants function as singlet and triplet oxygen quenchers, free radical scavengers, peroxide decomposers, and enzyme inhibitors [32,41,42]. ...
... The oxidant compound will change its color when it is reduced, and the degree of the color change depends on its concentration in the sample; examples of this assay are [61] as follows: a. DPPH (2,2 0 -diphenyl-1, 1 0 -picrylhydrazyl) assay: DPPH is a free radical that is unstable at room temperature; it can react by reducing the hydroxyl group(s) of the antioxidant molecules. The percentage of the scavenging activity of DPPH generally depends on the concentrations of the antioxidants [42]. This method is suitable for antioxidants that are soluble in organic solvents, especially alcohol. ...
Article
Many cosmetics that are marketed nowadays often contain antioxidants as the active ingredients. It is known that oxidation reactions could produce free radicals, which can start chain reactions that will damage skin cells. Increasing the amount of free radicals could initiate the wrinkling, photoaging, elastosis, drying, and pigmentation of the skin. Topical antioxidants could terminate the chain reactions by removing the free radical intermediates and inhibit other oxidation reactions by being oxidized themselves; this could defend the skin against the environmental stress caused by free radicals. It is well known that plants can produce natural antioxidant compounds that could control the oxidative stress caused by sunlight and oxygen. Many patents and commercial cosmetic products have various combinations of plant extracts. The cosmetic formulations usually contain various combinations of many plant extracts, for example, green tea, rosemary, grape seed, basil grape, blueberry, tomato, acerola seed, pine bark, and milk thistle. These plants extracts contain natural antioxidants, that is, polyphenols, flavonoids, flavanols, stilbens, and terpenes (including carotenoids and essential oils). Some commercial products contain pure natural compounds such as quercetin, kojic acid, and resveratrol in their formulation. The choice of the right active plant extracts or compounds, the confirmation of their activity, and their stability and synergistic effects in cosmetic products are the important factors for the formulation of an effective product.
... GA was also identified in E. hirsutum [26,27]. The phenolic acids contained in E. angustifolium, belonging to the group of hydroxybenzoic acids (GA, 4-BH, 3-HB, and 3,4-DBH), as well as to the group of hydroxycinnamic acids (ChA and CA), have antibacterial, anti-atherosclerotic, anticarcinogenic, and anti-inflammatory properties [28][29][30][31][32]. They are known to be scavengers of various oxygen species, even as toxic as the HO • radical and singlet oxygen [13]. ...
... Comparing the obtained results to the level of inhibition of the activity of these enzymes by their commonly known inhibitors, which were also used in this work, it can be concluded that this extract can be seen as a source of compounds with potential antiaging properties, protecting the elastin and collagen fibers from degradation. The possibility of inhibiting skin aging processes by other types of E. angustifolium extracts was also noticed by other authors [3,28]. Karakaya et al. showed that the extract of ethyl acetate from the aerial part of E. angustifolium showed wound healing, among others, by inhibiting collagenase enzymes, while the aqueous extract of E. angustifolium showed strong elastase inhibitory activities [28]. ...
... The possibility of inhibiting skin aging processes by other types of E. angustifolium extracts was also noticed by other authors [3,28]. Karakaya et al. showed that the extract of ethyl acetate from the aerial part of E. angustifolium showed wound healing, among others, by inhibiting collagenase enzymes, while the aqueous extract of E. angustifolium showed strong elastase inhibitory activities [28]. The naturally organic compounds found in E. angustifolium extracts include both primary and secondary metabolites. ...
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Epilobium angustifolium L. is a popular and well-known medicinal plant. In this study, an attempt to evaluate the possibility of using this plant in preparations for the care and treatment of skin diseases was made. The antioxidant, antiaging and anti-inflammatory properties of ethanolic extracts from Epilobium angustifolium (FEE) were assessed. Qualitative and quantitative evaluation of extracts chemically composition was performed by gas chromatography with mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The total polyphenol content (TPC) of biologically active compounds, such as the total content of polyphenols (TPC), flavonoids (TFC), and assimilation pigments, as well as selected phenolic acids, was assessed. FEE was evaluated for their anti-inflammatory and antiaging properties, achieving 68% inhibition of lipoxygenase activity, 60% of collagenase and 49% of elastase. FEE also showed high antioxidant activity, reaching to 87% of free radical scavenging using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 59% using 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Additionally, in vitro penetration studies were performed using two vehicles, i.e., a hydrogel and an emulsion containing FEE. These studies showed that the active ingredients contained in FEE penetrate through human skin and accumulate in it. The obtained results indicate that E. angustifolium may be an interesting plant material to be applied as a component of cosmetic and dermatological preparations with antiaging and anti-inflammatory properties.
... Elastase inhibitory activity 28 Elastase inhibition avoids the catalysis of the hydrolysis of elastin, a fibrous protein which determines the mechanical properties of tissues. 29 Elastase activity was examined by using Ala-Ala-Ala-p-nitroanilide as substrate and measuring the release of p-nitroanilide peptide at 410 nm. The assays were performed in 96-well plates as follows. ...
... Tyrosinase, a copper-containing enzyme, plays a key in melanogenesis by controlling the production of melanin. 29 Its monophenolase activity was examined using L-tyrosine as substrate, which is hydrolyzed to L-3,4-dihydroxyphenylalanine (L-DOPA). The aim is to find molecules reducing the overproduction of melanin and which could be skin whitening agents. ...
Article
Background: The current study presents new insight in the phytochemical content and biological activities of five Prunus domestica L. varieties ('Quetsche blanche de Létricourt', 'Mirabelle de Nancy', 'Perdrigon violet', 'Mirabelle de Provence' and 'Reine-claude dorée'). Results: The plum leaves were found to possess promising anti-ageing activities by their capacity to inhibit DPPH, elastase, hyaluronidase and lipoxygenase. After solid phase extraction (SPE), chlorogenic acid, rutin, quercetin and their derivatives were putatively identified by HPLC-ESI-MS/MS. Conclusion: The plum leaf, a by-product, provides interesting valuable source to be use as natural cosmetic product or as food supplements.
... In a similar approach, the outcome that we obtained from in vitro enzyme inhibitory activity assays also supported the previous studies on the extracts of E. angustifolium and E. hirsutum which demonstrated their hyaluronidase and lipoxygenase enzyme inhibitory activities with the IC 50 values of 5 μg/mL and 25 μg/mL (Kiss et al., 2011). Besides, it was reported that the aqueous extract of E. angustifolium showed strong elastase and lipoxygenase inhibitory activities with the EC 50 values of 42.72 μg/mL and 0.57 μg/mL, respectively (Onar et al., 2012). of E. angustifolium extract on normal human dermal fibroblasts (NHDF). The extract reduced stress-induced effects on NHDF, especially on connective tissue growth factor, fibronectin and matrix metalloproteinases (Ruszov� a et al., 2013). ...
... The extract reduced stress-induced effects on NHDF, especially on connective tissue growth factor, fibronectin and matrix metalloproteinases (Ruszov� a et al., 2013). Former investigations demonstrated that E. angustifolium, E. montanum, E. tetragonum, E. parviflorum, E. hirsutum, and E. roseum possess antioxidant activities (Toth et al., 2009a(Toth et al., , 2009bKiss et al., 2011;Onar et al., 2012;Ruszov� a et al., 2013;Granica et al., 2014). The mentioned antioxidant activity could probably be related with the rich phenolic ingredient (phenolic acids and ellagitannins) of E. angustifolium which was previously reported by Shikov et al. (2010). ...
Article
Ethnopharmacological relevance Epilobium species are generally known as “Yakı Otu” in Turkey, which mens “plaster herb” in English. Young shoots of Epilobium angustifolium L., Epilobium stevenii Boiss., and Epilobium hirsutum L. are consumed as salad or meal. These species have been used as a poultice for the treatment of mouth wounds in traditional medicine. An ointment prepared from leaves is used for skin disorders in children. Aim of the study We aimed to evaluate the ethnopharmacological use of Epilobium angustifolium, E. stevenii, and E. hirsutum by using in vivo and in vitro experimental models, and to identify the active wound-healer compound(s) and to explain the probable mechanism of the wound-healing activity. Materials and methods Evaluation of wound healing effects of plant extracts was performed in rats and mice by linear incision and circular excision wound models. Determination of total phenolic constituents and antioxidant capacities, which are known to promote the wound healing process, were carried out through Folin-Ciocalteau method and 2,2 Diphenyl 1 picrylhydrazyl (DPPH) scavenging assay as well as determination of total antioxidant status (TAS) and total oxidant status (TOS) on the treated tissues. The active ethyl acetate (EtOAc) sub-extract of E. angustifolium was fractionated by different chromatographic separation techniques. The structures of isolated compounds were elucidated via detailed analyzes (NMR and LC/MS). In addition, in vitro collagenase, hyaluronidase, and elastase enzymes inhibitory activity tests were performed on the isolated compounds to discover the activation pathways of the samples. Results Among the methanol (MeOH) extracts, E. angustifolium had the highest wound healing activity. Among the sub-extracts, EtOAc showed the highest wound healing activity. Thus, EtOAc sub-extract was subjected to chromatography to isolate the active compounds. Five known flavonoids namely hyperoside (quercetin-3-O-β-D-galactoside) (1), kaempferol (2), kaempferol-3-O-α-L-rhamno pyranoside (3), quercetin-3-O-α-L-rhamno pyranoside (4), and quercetin-3-O-α-L-arabino pyranoside (5) were isolated from the EtOAc sub-extract of E. angustifolium. In vitro tests showed that hyperoside could be the compound responsible for the wound-healing activity by its significant anti-hyaluronidase, anti-collagenase, and antioxidant activities. Conclusion The EtOAc sub-extract of the aerial part of Epilobium angustifolium displayed remarkable wound-healing activity with anti-hyaluronidase, anti-collagenase, and antioxidant activities. Hyperoside was detected as the primary active compound of the aerial parts. According to the results, we suggest that EtOAc sub-extract of E. angustifolium and hyperoside may be a potent nominee to be used for the improvement of a wound-healing agent.
... Les lipoxygénases, protéines enzymatiques capables de catalyser la dioxygénation des acides gras polyinsaturés constituant les lipides, sont très impliquées dans ce processus. Elles participent activement à la biosynthèse des leucotriènes*, principaux médiateurs du processus inflammatoire [163], et jouent un rôle important dans la croissance cellulaire, dans le développement de métastases, ou encore dans l'expression du facteur de croissance TNF (facteur de nécrose tumorale) [164]. Un ingrédient capable de moduler l'activité d'une/des lipoxygénases, est capable d'agir sur la phase inflammatoire du processus de réparation cutanée. ...
... La lipoxygénase catalyse l'incorporation régiospécifique et stéréospécifique de dioxygène sur le système pentadiénique d'un acide gras libre polyinsaturé tel que l'acide linoléique, pour générer un hydroperoxyde d'acide gras ( Figure 12) [165]. La formation de cet hydropéroxyde peut être suivie par spectrophotométrie UV à 234 nm, et permet de déterminer le pouvoir antiinflammatoire d'un extrait ou d'un composé [164]. ...
Thesis
Le secteur cosmétique est gouverné par les demandes des consommateurs en quête de produits naturels à l’efficacité démontrée, auxquelles les formulateurs répondent en y intégrant des actifs naturels et éco-conçus. Ces travaux de thèse portent sur le développement de tels actifs cosmétiques innovants favorisant la réparation cutanée à partir de matières premières naturelles d’origine méditerranéenne. Les activités biologiques d’une centaine d’extraits naturels obtenus à partir de 77 matières végétales ont été évaluées à l’aide de tests in vitro (activités antioxydantes, anti-inflammatoires et anti-âge -activités anti-hyaluronidase, anti-collagénase et anti-élastase-). Un total de 28 matières premières végétales se sont avérées particulièrement intéressantes en termes d’activités biologiques parmi lesquelles trois ont été sélectionnées pour la poursuite de cette étude. La germandrée lisse (Teucrium lucidum L.) a été choisie car il s’agit d’une plante endémique de la région méditerranéenne très peu étudiée. Le chêne pubescent (Quercus pubescens Willd.) et le prunier de Brignoles (Prunus domestica L.) ont été sélectionnés car il s’agit de co-produits de l’agriculture régionale, qu’il est par conséquent très intéressant de valoriser. Cette étude a porté principalement sur la caractérisation phytochimique d’extraits de germandrée lisse obtenus par macération des parties aériennes, et favorisant la réparation cutanée. Huit composés principaux ont été isolés puis identifiés par RMN ; seuls trois d’entre eux avaient déjà été décrits dans le genre Teucrium. Cinq autres composés qui n’avaient pas été décrits précédemment dans T. lucidum ont également été caractérisés. Cette étude a aussi permis de mettre en place une méthodologie de développement d’ingrédients cosmétiques naturels liquides et solides, de l’approvisionnement en matière première végétale, jusqu’à leur intégration dans un produit cosmétique fini. Cette méthodologie a été mise en place à travers l’étude des deux co-produits sélectionnés lors du criblage, à savoir le chêne pubescent et le prunier de Brignoles, et a permis d’identifier les étapes à adapter d’une matière première à l’autre, selon sa composition phytochimique.
... The mushroom tyrosinase (EC 1.14.18.1) inhibitory activity was determined using L-Dopa as the substrate, according to the method reported by Onar et al. [25]. The mushroom tyrosinase (EC 1.14.18.1) was prepared into 1000 units/mL and was used in 0.02 mL. ...
Article
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Polysaccharides from Volvariella volvacea (VVP) were investigated for their cosmetic-related activities and in vivo efficacy for use as a multifunctional active cosmetic ingredient. Three different polysaccharide extraction methods, including hot water shaking (HS), microwave-assisted (MA) and ultrasonic-assisted (UA), were used. Extractable yield, polysaccharide contents and biological activities, including antioxidant, anti-tyrosinase and anti-elastase activities, were compared. The polysaccharides from HS provided the highest extraction yield (15.58 ± 0.96% w/w) and the highest beta-glucan content (18.80 ± 0.81% w/w). The HS polysaccharides also possessed the highest inhibitory effects toward lipid peroxidation (IC50 of 0.0378 mg/mL), tyrosinase (51.46 mg KAE/g), and elastase (604.21 ± 73.66 mg EGCG/g). The cytotoxicity of the VVP was determined for safe use. A cosmetic gel cream containing VVP was developed and 0.2% VVP formulation was observed to be the most stable in color. UV protection factors, skin irritation by single patch test, and in vivo efficacy, including skin moisturization, anti-wrinkle and whitening, were measured. The VVP showed no cytotoxicity against human dermal skin fibroblast. The gel cream containing VVP provided less sun protection factor; however, it significantly exhibited the skin benefits of increasing moisture, gross elasticity, net elasticity, and skin firmness. Improvements to skin roughness, scaliness, wrinkles and in melanin content were also depicted gradually along 8 weeks. V. volvacea, therefore, could be a good source for polysaccharides being used as a moisturizing, anti-wrinkle, and whitening agent in cosmetic preparations.
... Chemical analyses had indicated the presence of alkaloids, glycosides, tannins, and flavonoids in the crude ethanolic extract most of which are known to possess potent antioxidant activity. The results of antioxidant activity indicate higher free radical scavenging activity (Onar et al., 2012). ...
... However, due to insufficient clinical data, no medicinal products with predefined indication are commercially available in Europe (Kujawski et al., 2011;Stolarczyk et al., 2013a). Rosebay willow-herb shows antioxidative, anti-inflammatory, antimicrobial, antiproliferative, and anti-exudative activities (Hevesi Toth et al., 2009;Kiss et al., 2011;Kosalec et al., 2013;Onar et al., 2012;Stolarczyk et al., 2013b;Vitalone et al., 2001Vitalone et al., , 2003Vogl et al., 2013). The anti-inflammatory activity of E. angustifolium has been closely related to its flavonoids evidenced by the finding of myricetin 3-O-glucuronide as strongly active (4 10-fold more potent than indomethacin) in the rat paw edema test, a model of acute inflammation (Hiermann et al., 1998) and showing an inhibitory effect on prostaglandin biosynthesis (Hiermann et al., 1991). ...
Article
Flavonoids are regarded as essential ingredients for the anti-inflammatory activity of Epilobium angustifolium L. (Onagraceae). The metabolic profiles of medicinal plants vary aside from genetic determination due to the influence by external factors. This study evaluates the influence of altitudinal variation on the content of flavonoids in E. angustifolium in two consecutive growing periods. Aerial and herbaceous plant materials were collected at three different altitudes (800, 1000, and 1500 m) during two collection periods. Plant samples (11-13 samples per altitude and year) were extracted with methanol using accelerated solvent extraction (ASE). Identification and quantification of the constituents were achieved by chromatographic means of HPLC-PDA and LC-PDA-MS analyses. Rising concentrations of flavonol 3-O-glycosides could be detected with increasing altitude. The content of the major compound, quercetin 3-O-glucuronide, ranged from 4.4 ± 2.05 (800 m) to 4.9 ± 1.03 (1000 m) and up to 6.6 ± 1.14 mg/g (1500 m). The total amount of flavonol 3-O-glycosides in 73 analyzed samples ranged from 10.7 ± 1.37 up to 17.3 ± 1.99 mg/g. Quercetin-3-O-glucuronide can be considered as a potential marker for the increased production of flavonols in herbal parts of E. angustifolium at higher altitudinal levels. The study confirms that environmental factors at higher altitude result in elevated levels of flavonols in aerial plant tissues of E. angustifolium. Specific factors for influencing the flavonoid content have to be clarified in further studies.
... Higher OH radical scavenging activity was observed in the acetone extract of T. lactinea and this might be connected to its higher total phenolic content. The observation corresponds with the findings of Onar et al. (2012) who observed high correlation between hydroxyl radical scavenging activity and phenolic compounds of aqueous extract of Epilobium angustifolium. Result from this study show that drugs for the prevention of OH radical induced DNA damage could be sourced from Trametes lactinea. ...
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The total phenolic and flavonoid contents, as well as the in vitro radical scavenging potentials of extracts of Trametes lactinea collected from forest near the Teaching and Research farm of the Federal University of Technology, Akure were assessed. The acetone extract possessed higher total phenolic content (3.21 mg GAE g-1), whereas, the methanol extract had higher total flavonoid content (1.46 mg RE g-1). All the extracts were able to scavenge 1, 1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO), hydrogen peroxide (H2O2) and hydroxyl (OH) radicals. At a concentration of 2 mg L-1 the extracts produced activities greater than 50%. The observed result indicates that this wild macrofungus, Trametes lactinea could be a valuable source of natural antioxidants that can protect against free radicals mediated damages.
... Elastase is a metalloproteinase enzyme that is capable of degrading elastin, even though it is quite resistant against proteolytic degradation, continuous exposure to elastases leads to damage of elastic fibres thus leading to declined skin resilience and wrinkles. Elastase activity has been reported to increase significantly with age and as a result, interest to screen natural matrices such as plants, mushrooms, rhizomes and marine algae for production of active cosmetic ingredients able to reduce skin aging and wrinkles have increased (Onar et al., 2012). ...
... A significant increase of elastase activity has been described with age, and therefore, there has been an increased interest in natural compounds to reduce skin aging and wrinkles. 91 Collagen is the most important ECM component and is responsible for flexibility, elasticity, and skin resistance. Its degradation may be induced by UVR. ...
Article
Nutrition is one of the most important parameters involved in modulating skin health and condition. In this regard, the demand for natural compounds capable of promoting skin health and beauty has been attracting the attention of researchers and companies around the world. An interesting option to meet this demand is the use of Spirulina microalga, which has biotechnological potential, including several functional and nutritional applications. Although this microalga has been used in human nutrition since ancient times, it now has new applications and is being studied as a promising ingredient for nutricosmetics. The present review article summarizes Spirulina's most relevant activities, mainly its biologically active metabolites, which are interesting ingredients for nutricosmetic formulations and an important advance for skin care.
... The inhibition of skin elastase and tyrosinase serves a key role in the antiwrinkle and skin-evening activities (4,7,33). Antioxidant polyphenols possess tyrosinase and elastase inhibitory activity (4,36,39). In the current study, the extract from burdock leaves with antioxidant polyphenols inhibited elastase and tyrosinase activity, with their antielastase activity being stronger compared with their antityrosinase activity, which can be explained using the ROS scavenging theory of skin aging (40). ...
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Burdock (Arctium lappa L.) leaves generate a considerable amount of waste following burdock root harvest in Taiwan. To increase the use of burdock leaves, the present study investigated the optimal methods for producing burdock leaf extract (BLE) with high antioxidant polyphenolic content, including drying methods and solvent extraction concentra­tion. In addition, the elastase and tyrosinase inhibitory activity of BLE was examined. Burdock leaves were dried by four methods: Shadow drying, oven drying, sun drying and freeze-drying. The extract solution was then subjected to total polyphenol content analysis and the method that produced BLE with the highest amount of total antioxidant components was taken forward for further analysis. The 1, 1-diphenyl-2-pycrylhydrazyl scavenging, antielastase and antityrosinase activity of the BLE were measured to enable the evaluation of the antioxidant and skin aging-associated enzyme inhibitory activities of BLE. The results indicated that the total polyphenolic content following extraction with ethanol (EtOH) was highest using the freeze-drying method, followed by the oven drying, shadow drying and sun drying methods. BLE yielded a higher polyphenol content and stronger antioxidant activity as the ratio of the aqueous content of the extraction solvent used increased. BLE possesses marked tyrosinase and elastase inhibitory activities, with its antielas­tase activity notably stronger compared with its antityrosinase activity. These results indicate that the concentration of the extraction solvent was associated with the antioxidant and skin aging-associated enzyme inhibitory activity of BLE. The reactive oxygen species scavenging theory of skin aging may explain the tyrosinase and elastase inhibitory activity of BLE. In conclusion, the optimal method for obtaining BLE with a high antioxidant polyphenolic content was freeze-drying followed by 30-50% EtOH extraction. In addition, the antielas­tase and antityrosinase activities of the BLE produced may be aid in the development of skincare products with antiwrinkle and skin-evening properties.
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Background: Pithecellobium dulce (Roxb.) Benth., Securidaca longepedunculata Fresn and Cryptolepis sanguinolenta (Lindl.) Schlt are three plants widely used in the Togolese traditional medicine to treat microbial infections. Some studies reported their antibacterial activity alone but until know there no data concerning their possible interaction with conventional antibiotics. The main objective of this study was to investigate the antibacterial activity of the association of the crude extracts of the three plants with some conventional antibiotics. We further evaluate the antioxidant and the anti-inflammatory activities of the extracts on rat’s model. Materials and methods:The antimicrobial activity was evaluated by the broth microdilution assay and the Fractional inhibitory concentrations (FIC) determined by the checkerboard method. The anti-inflammatory activity was evaluated using the Carrageenan- induced rat paw edema model. The antioxidant activities and the phenol contents were determined by spectrophotometry. Results: The MICs of hydroethanolic extract of plants ranged from 3.125 to 100 mg/mL on Klebsiella pneumoniae strains. Synergistic action was observed only with the combination of Imipenem/P. dulce, imipenem/C. sanguinolenta, amikacin/P. dulce and amikacin/C. sanguinolenta against the ESBL negative Klebsiella pneumoniae strain. Of the 21 associations, 15 were antagonistic on the ESBL-producing strains. The indifference effect was observed with the combination of the extract of Securidaca longepedunculata and the following antibiotics imipenem, amikacin, tetracyclin, ciprofloxacin, Cefotaxim; and Sulfametoxazol+Trimethoprim. The in vitro anti-inflammatory with Lipoxygenase inhibition activity was best with C. sanguinolenta extract while the in vivo paw edema model revealed that S. longepedunculata was the highest reducer of paw edema. In addition white blood cells count and biochemical parameters such as total proteins and immunoglobulins were significantly affected by the administration of plant extracts. Conclusion: This study revealed that the three plants although they may inhibit the bacterial growth by themselves, but there is also a possible synergistic action with the commercial antibiotics. Further investigations are needed to identify the active compounds and their mechanism of action.
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Elastazlar (E.C. 3.4.21.36), bağ dokunun önemli bir proteni olan elastini ayırma özelliğine sahip bir grup serin proteazlardır. Bu çalışmada, Giresun yöresinde yetişen 15 çeşit yenilebilir bitkinin farklı çözücülerdeki ekstrelerinin, elastaz enzim aktivitesi üzerindeki inhibitör etkisi incelendi. Bu amaçla, su, metil alkol ve etil asetat ile hazırlanan ekstrelerinin elastaz aktivitesi üzerine inhibitör etkileri spektrofotometrik olarak analiz edildi. Bu bitkiler arasında, kara lahananın (Brassica oleracea) sulu ekstresinin (IC50= 0,0002 ± 0,0001 µg/mL), söğüt otunun (Polygonum lapathifolium) metil alkollü ekstresinin (IC50= 0,0003 ± 0,0002 µg/mL) ve mendeğin (Aegopodium podagraria) etil asetatlı ekstresinin (IC50=0,0007 ± 0,0001 µg/mL) elastaz enzimine karşı en yüksek inhibitör etkisine sahip olduğu bulundu. Analizlerin sonucunda, bitki ekstrelerinin elastaz üzerinde farklı inhibitör etkilerine sahip oldukları belirlendi. Çalışmada elde edilen sonuçlar, çalışılan bitkilerin alternatif bir anti-elastaz kaynağı olarak kullanılabileceğini açıkça göstermektedir.
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The biological properties of ethanolic (50%, v/v) extracts from Oenothera biennis, Borago officinalis, Nigella sativa seedcake before and after enzymatic hydrolysis by alpha-amylase (EC 3.2.1.1) from Aspergillus oryzae, beta-glucosidase (EC 3.2.1.21) and beta-glucanase (EC 3.2.1.6) from Aspergillus niger combinations in a ratio of 1:1:1 were investigated. Total phenolic, flavonoid and reducing sugar content for O. biennis extract after enzymatic hydrolysis was, respectively, 0.5, 1.5 and 2 times higher in comparison with nonhydrolysed extract. Iron-chelating and inline image radical-scavenging activity of O. biennis seedcake extract after hydrolysis (IC50 = 0.076 mg mL−1 and IC50inline image = 0.050 mg mL−1) was at a similar level as that nonhydrolyeed (IC50 = 0.070 mg mL−1 and IC50inline image = 0.065 mg mL−1). The antioxidant activity was two times higher after hydrolysis than before enzymatic hydrolysis of O. biennis seedcake extract. Also strong elastase inhibition activity has been shown to O. biennis seedcake extract before (IC50 = 0.095 mg mL−1) and after enzymatic hydrolysis (IC50 = 0.07 mg mL−1), respectively. Oenothera biennis and B. officinalis seedcake extracts before and after hydrolysis have stronger antibacterial activity against Pseudomonas aeruginosa strain in comparison with N. sativa seedcake.
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Many modalities of treatment for acquired skin hyperpigmentation are available including chemical agents or physical therapies, but none are completely satisfactory. Depigmenting compounds should act selectively on hyperactivated melanocytes, without short- or long-term side-effects, and induce a permanent removal of undesired pigment. Since 1961 hydroquinone, a tyrosinase inhibitor, has been introduced and its therapeutic efficacy demonstrated, and other whitening agents specifically acting on tyrosinase by different mechanisms have been proposed. Compounds with depigmenting activity are now numerous and the classification of molecules, based on their mechanism of action, has become difficult. Systematic studies to assess both the efficacy and the safety of such molecules are necessary. Moreover, the evidence that bleaching compounds are fairly ineffective on dermal accumulation of melanin has prompted investigations on the effectiveness of physical therapies, such as lasers. This review which describes the different approaches to obtain depigmentation, suggests a classification of whitening molecules on the basis of the mechanism by which they interfere with melanogenesis, and confirms the necessity to apply standardized protocols to evaluate depigmenting treatments.
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We have been actively involved in the isolation and characterization of endogenous plant antioxidants that are believed to inhibit lipid peroxidation and offer protection against oxidative damage to membrane functions. Antioxidants have been isolated from conventional food sources, such as tea (green and black), sesame and wild rice, and also from other plant sources, such as rice hulls, and crude plant drugs. Data on new types of water-soluble and lipid-soluble plant antioxidants are provided, and the biological activity and functionality of these antioxidants are discussed.
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The ABTS/H2O2/HRP decoloration method permits the evaluation of the antioxidant activity of complex food samples. This method, with slight modifications, is capable of determining both hydrophilic and lipophilic antioxidant properties, thus, it is possible estimate the antioxidant activity of both antioxidant types in the same sample. The method is easy, accurate and rapid to apply. Its application to three vegetable soups provided data on hydrophilic and lipophilic antioxidant activity, and the values reflect the contribution of the particular antioxidants (ascorbic acid and carotenoids) to the total antioxidant activity of the samples.
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Antioxidant activities of buckwheat seeds, dehulled seeds, hulls, straws and leaves were evaluated and compared with those of oats and barley. Schaal oven test at 70 °C with gravimetric indication and lard as the substrate was applied. Protection factors ranged from 1.3 to 8.0 and increased in the order: buckwheat straws < buckwheat hulls = oats <barley <buckwheat seeds <buckwheat dehulled seeds <buckwheat leaves. Methanol extract of buckwheat seeds showed higher antioxidant activity in comparison with petrolether extract, protection factors amounted to 2.9 and 1.9, respectively Total phenolics, rutin and tocol contents in tested samples were determined and related to the antioxidant activities. Statistically significant relationship between total phenolics content as well as rutin content and antioxidant activity of buckwheat material was observed (R2 = 0.987, P <0,002, R2 = 0.972, P<0.002, respectively) Significant correlation between tocol content and antioxidant activity was not found.
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Willow herb tea or preparation are available and relatively popular in the European market, and claimed to be effective inter alia because of their anti-inflammatory activity. The present study is therefore aimed at comparing the anti-inflammatory and antioxidant activity of extracts of the three most popular Epilobium species (E. angustifolium, E. hirsutum and E. parviflorum) and at juxtaposing this activity against the dominating compounds from the following extracts: oenothein B (OeB), quercetin-3-O-glucuronide and myricetin-3-O-rhamnoside. The phytochemical analysis of the extracts has shown that OeB quantities vary between 20% and 35%, while flavonoids content does not exceed 2%. All extracts have inhibited the activity of hyaluronidase and lipoxygenase with IC₅₀ around 5 μg/ml and 25 μg/ml. The inhibition of hyaluronidase is related with the presence of OeB, a strong inhibitor of this enzyme (IC₅₀) 1.1 μM). Additionally, the extracts inhibited myeloperoxidase (MPO) release from stimulated neutrophils. OeB inhibited MPO release similarly to the anti-inflammatory drug indomethacin with IC₅₀ 7.7 μM and 15.4 μM, respectively. Tested extracts significantly reduced the production of reactive oxygen species (ROS) from f-MLP and PMA induced neutrophils with IC₅₀ 5 μg/ml and 25 μg/ml, respectively. The flavonoids content seems to exert little influence on extracts' activity, contrary to OeB, whose high concentration explains the activity of extract obtained from Epilobium. Tested currently marketed Epilobium preparations are often wrongly assigned, but we should stress that the level of OeB in all tested herbs was high and always exceeded 2% in raw material.
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Taiuiá or tayuya (Cayaponia tayuya, Cucurbitaceae) is a climbing, lignified plant with a large swollen root that has traditionally been used as an anti-inflammatory and anti-rheumatic agent in the folk medicine of Brazil, Peru, and Colombia. We have assayed the pharmacological properties of a flavonoid fraction obtained from the butanol extract of Cayaponia tayuya roots using two models of topical mouse ear oedema, paying special attention to its influence on the induction on pro-inflammatory enzymes and peptidic mediators. The in vivo experiments involved both the acute oedema induced by a single application of TPA and the subchronic inflammation brought on by repeated applications of TPA. The effects on the induction of pro-inflammatory enzymes and peptidic mediators in RAW 264.7 macrophages were analyzed with the aid of Western blot analysis. The extract was identified as a mixture of flavonoids in which vicenin-2, spinosin, isovitexin, and a mixture of swertisin and isoswertisin were found. In acute TPA-induced oedema in mouse ears, the flavonoid-enriched fraction (at a dose of 0.5mg/ear) inhibited the oedema by 66% (4.2+/-0.6 mg vs. 12.3+/-1.4 mg, P<0.01) while in the subchronic model, the inhibition reached 37% at a dose of 0.5mg/ear x 7 applications (7.5+/-0.6 mg vs. 11.9+/-1.3mg, P<0.05). When assayed in vitro, the flavonoid showed no toxicity at 33.45 microg/mL on RAW 264.7 macrophages. Although the nitric oxide production in these cells was moderately reduced (42%) at 33.45 microg/mL, the flavonoid-enriched fraction had no effect on TNF-alpha production. In addition, at 22.30 microg/mL, the test sample inhibited both iNOS and COX-2 expression by 98% and 49%, respectively. These results indicate that the anti-inflammatory activity of flavonoids from tayuya roots most likely stems from their inhibition of the induction of the enzymes COX-2 and iNOS.
Activated oxygen species which may be important in initiating oxidative changes in foods include singlet oxygen, hydroxyl radical, ozone, superoxide anion (perhydroxyl radical at low pH), and hydrogen peroxide. Chemical and enzymic reactions known to occur in biological materials can generate singlet oxygen, hydroxyl radical, superoxide anion, and hydrogen peroxide. Ozone is primarily a product of photoreactions in polluted air. Reactions involving singlet oxygen, hydroxyl radical, and ozone with food constituents can ultimately yield peroxides which decompose to initiate oxidative chain reactions. Superoxide anion and hydrogen peroxide are relatively inert toward organic molecules but can decompose to produce the more reactive singlet oxygen and hydroxyl radical. Inhibition of reactions initiated by reactive oxygen species in foods should be very important in preserving the oxidative stability of foods. The generation, detection, measurement, reaction, and inhibition of reactions of active oxygen species are surveyed in this review.
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Epilobium species have been used as remedies in folk-medicine for the treatment of pathophysiological processes of the prostata. In this paper the influence of extracts of Herba Epilobii angustifolii L. and Herba Epilobii parviflori Schreb. on prostaglandin biosynthesis and the carrageenin rat paw oedema is described. Aqueous extracts of Herba E. angustifolii reduced the release of prostaglandins I2, E2 and D2 (in the perfused rabbit ear) approximately 5 times more effectively than did similar extracts of Herba E. parviflori. Methanolic extracts were inactive. The aqueous extract of E. angustifolium strongly reduced the carrageenin-induced rat paw oedema whereas that of E. parviflorum was inactive. The chemical nature of the active compound(s) is as yet unknown but flavonoids and sitosterol derivatives can be excluded.
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The interactions of three BPTI homologues with human leukocyte elastase and porcine pancreatic elastase have been investigated. The principal mutation in determining the specificity of inhibition was the Lys15-Val mutation at the P1 position. An additional mutation at P3, i.e., BPTI (Lys15-Val, Pro13-Ile), increased the inhibition of HLE to a Ki = 2.5 x 10(-10) M, but decreased the inhibition of PPE, showing this to be a useful site for improving selectivity. Kinetic evidence suggests that the inhibition of HLE by BPTI homologues probably takes place by a two-step mechanism in which an isomerization step occurs after initial binding. 1H NMR spectroscopy of the BPTI (Lys15-Val) and BPTI (Lys15-Val, Pro13-Ile) mutants indicates that small conformational changes are associated with the mutations, but these are localized in the immediate vicinity of the mutation in the outer binding loop and in the inner loop connected to it through the Cys14-Cys38 disulfide bridge.
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The alcoholic extract of Acanthus ilicifolius leaves inhibited the formation of oxygen derived free radicals (ODFR) in vitro with IC(50) of 550 microg/ml, 2750 microg/ml, 670 microg/ml and 600 microg/ml (Fe(2+)/ascorbate system), 980 microg/ml (Fe(3+)/ADP/ascorbate system) for superoxide radical production, hydroxyl radical generation, nitric oxide radical formation and lipid peroxide formation, respectively. The oral administration of the extract (250 and 500 mg/kg) significantly reduced CCl(4) induced hepatotoxicity in rats, as judged from the serum and tissue activity of marker enzymes [glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and alkaline phosphatase (ALP)]. These results were comparable with those obtained with curcumin (100 mg/kg, p.o.).
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A series of N-substituted N-nitrosohydroxylamines including six new compounds were synthesized and examined for inhibition of mushroom tyrosinase. Corresponding hydroxylamines were reacted with n-butyl nitrite to give substituted nitrosohydroxylamines as their ammonium salt. The N-substituted hydroxylamines were prepared from the primary amines via the oxaziridine, or from the carbonyl compounds via the oxime. Most of the nitrosohydroxylamines tested inhibited mushroom tyrosinase. Among them, N-cyclopentyl-N-nitrosohydroxylamine exhibited the most potent activity (IC(50)=0.6 microM), as powerful as that of tropolone, one of the most powerful inhibitors. As removal of nitroso or hydroxyl moiety, the enzyme inhibitory activity was completely diminished. Both N-nitroso group and N-hydroxy group were suggested to be essential for the activity, probably by interacting with the copper ion at the active site of the enzyme. Lineweaver-Burk plotting showed that cupferron was a competitive inhibitor but that N-cyclopentyl-N-nitrosohydroxylamine was not.
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The antimicrobial activity of the Epilobium angustifolium, E. hirsutum, E. palustre, E. tetragonum and E. rosmarinifolium ethanolic extracts was studied in vitro on Gram-positive and Gram-negative bacteria, yeasts and fungi. The cytotoxicity of the extracts was also evaluated using the Artemia salina test. All the extracts showed antimicrobial activity in a range of concentrations between 10 and 650 microgml of dry extract. E. angustifolium and E. rosmarinifolium had the most broad spectrum of action inhibiting bacteria, yeasts and fungi. The extracts were devoid of toxicity on Artemia salina within the range of antimicrobial concentrations, suggesting that the action is selective on microorganisms.
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Flavones and isoflavones may play a prominent role in cancer prevention since these compounds are found in numerous plants that are associated with reduced cancer rates. This article reviews recent epidemiological and animal data on isoflavones and flavones and their role in cancer prevention. It covers aspects of the bioavailability of these dietary constituents and explores their mechanism of action. Human epidemiology data comes primarily from studies in which foods rich in isoflavones or flavones are associated with cancer rates. This approach has been particularly useful with isoflavones because of their abundance in specific foods, including soy foods. The bioavailability of flavones and isoflavones has been shown to be influenced by their chemical form in foods (generally glycoside conjugates), their hydrophobicity, susceptibility to degradation, the microbial flora of the consumer, and the food matrix. Some information is available on how these factors influence isoflavone bioavailability, but the information on flavones is more limited. Many mechanisms of action have been identified for isoflavone/flavone prevention of cancer, including estrogenic/antiestrogenic activity, antiproliferation, induction of cell-cycle arrest and apoptosis, prevention of oxidation, induction of detoxification enzymes, regulation of the host immune system, and changes in cellular signaling. It is expected that some combination of these mechanisms will be found to be responsible for cancer prevention by these compounds. Compelling data suggest that flavones and isoflavones contribute to cancer prevention; however, further investigations will be required to clarify the nature of the impact and interactions between these bioactive constituents and other dietary components.
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Tyrosinase, also known as polyphenol oxidase, is a copper-containing enzyme, which is widely distributed in microorganisms, animals, and plants. Nowadays mushroom tyrosinase has become popular because it is readily available and useful in a number of applications. This work presents a study on the importance of tyrosinase, especially that derived from mushroom, and describes its biochemical character and inhibition and activation by the various chemicals obtained from natural and synthetic origins with its clinical and industrial importance in the recent prospects.
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Dopamine (DA)- or L-dihydroxyphenylalanine-(L-DOPA-) induced neurotoxicity is thought to be involved not only in adverse reactions induced by long-term L-DOPA therapy but also in the pathogenesis of Parkinson's disease. Numerous in vitro and in vivo studies concerning DA- or L-DOPA-induced neurotoxicity have been reported in recent decades. The reactive oxygen or nitrogen species generated in the enzymatical oxidation or auto-oxidation of an excess amount of DA induce neuronal damage and/or apoptotic or non-apoptotic cell death; the DA-induced damage is prevented by various intrinsic and extrinsic antioxidants. DA and its metabolites containing two hydroxyl residues exert cytotoxicity in dopaminergic neuronal cells mainly due to the generation of highly reactive DA and DOPA quinones which are dopaminergic neuron-specific cytotoxic molecules. DA and DOPA quinones may irreversibly alter protein function through the formation of 5-cysteinyl-catechols on the proteins. For example, the formation of DA quinone-alpha-synuclein consequently increases cytotoxic protofibrils and the covalent modification of tyrosine hydroxylase by DA quinones. The melanin-synthetic enzyme tyrosinase in the brain may rapidly oxidize excess amounts of cytosolic DA and L-DOPA, thereby preventing slowly progressive cell damage by auto-oxidation of DA, thus maintainng DA levels. Since tyrosinase also possesses catecholamine-synthesizing activity in the absence of tyrosine hydroxylase (TH), the double-edged synthesizing and oxidizing functions of tyrosinase in the dopaminergic system suggest its potential for application in the synthesis of DA, instead of TH in the degeneration of dopaminergic neurons, and in the normalization of abnormal DA turnover in the long-term L-DOPA-treated Parkinson's disease patients.
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The inhibition of tyrosinase is one of the major strategies to treat hyperpigmentation. Various limitations are associated with many of these inhibitors, such as high cytotoxicity, poor skin penetration and low stability in formulations. In continuation of our previous study [J. Agric. Food Chem. 51 (2003) 1201], showing that isoliquiritigenin chalcone (ILC) is a potent tyrosinase inhibitor, the present study aims to characterize the chalcone family as new tyrosinase inhibitors, and demonstrate their potential whitening potency. Nine mono-, di-, tri- and tetrahydroxychalcones were tested as inhibitors of tyrosinase mono- and diphenolase activities, showing that the most important factor in their efficacy is the location of the hydroxyl groups on both aromatic rings, with a significant preference to a 4-substituted B ring, rather than a substituted A ring. Neither the number of hydroxyls nor the presence of a catechol moiety on ring B correlated with increasing tyrosinase inhibition potency. 4-Hydroxychalcone (4-HC), ILC and Butein inhibited tyrosinase and shortened the lag period of enzyme monophenolase activity from about 490 min (control) to 30 min (ILC). As pigmentation also results from auto-oxidation, the antioxidant activity of 4-HC, ILC and Butein, were tested. Results showed that chalcones are also potent antioxidants, with Butein the most potent. We may conclude that chalcones are potentially potent new depigmentation agents, with their double effect of reduction and antioxidant activity. A deeper understanding of the relation between their structures to their potency will contribute to designing the optimal agents.
Article
In order to develop a new skin whitening agent, safflower (Carthamus tinctorius L.) seeds were evaluated for melanogenesis inhibitory activity and its active principles were identified following activity-guided isolation. The 80% aqueous methanol extract and ethyl acetate fraction from safflower seeds showed a significant inhibition for mushroom tyrosinase. Three active compounds, N-feruloylserotonin, N-(p-coumaroyl)serotonin, and acacetin, were isolated from the ethyl acetate fraction as the active principles. Compared with arbutin (IC50=0.223 mM), the IC50 values of these compounds were 0.023, 0.074, and 0.779 mM for N-feruloylserotonin, N-(p-coumaroyl)serotonin, and acacetin, respectively. It was also found that N-feruloylserotonin and N-(p-coumaroyl)serotonin strongly inhibited the melanin production of Streptomyces bikiniensis and B16 melanoma cells in comparison with a known melanogenesis inhibitor, arbutin.
Article
The present study has been performed to evaluate the antimutagenic activity of quercetin, ascorbic acid and their combination against an oxidative mutagen. An effort was also made to correlate this activity to the in vitro antioxidant activity of these agents. Antimutagenicity testing was done in Ames Salmonella Assay system using Salmonella typhimurium TA102 against t-butylhydroperoxide as an oxidative mutagen. In vitro antioxidant scavenging activity was tested for DPPH free radical, superoxide anion, hydrogen peroxide and hydroxyl radical in their specific test systems. Quercetin (0.5-8 nmole/plate) and ascorbic acid (0.1-100 micromole/plate) showed significant effect. Quercetin (4 and 8 nmole/plate) when combined with ascorbic acid (500 nmole/plate) showed an increase in the antimutagenic activity. In vitro antioxidant activity of quercetin was better than ascorbic acid in all the test systems used. The study indicated that the antimutagenic activity of quercetin was not solely accountable by its antioxidant nature. However, in vitro free radical scavenging activity of quercetin correlated well with the antimutagenic activity.
Article
Many studies have been conducted to find a natural material that has high biologic functions for human skin without any side effects. Persimmon leaf has a substantial amount of tannins in different forms; therefore, it was selected as a target material. The biosynthesis rate of the collagen was also investigated to clarify the beneficial functions for the human skin. Persimmon leaves were obtained, extracted with 80% ethanol, and isolated into PFs I, II, and III after column chromatography using a Sephadex LH-20 column followed by thin-layer chromatography. The xanthine oxidase inhibition effect of both PFs II and III was over 40% at a 100 ppm concentration. PF II, containing higher flavonoids levels, had a significantly higher tyrosinase inhibition than that of PF III. Collagenase inhibition was 16.3 and 8.1% for PF III and PF II, respectively, at 100 ppm. On the other hand, elastase inhibition activity was significantly higher in PF II than PF III. Collagen biosynthesis rates of PF III were over 25% from a 1 to 10 ppm concentration. Consequently, PFs isolated from the persimmon leaf can be used as natural materials or additives for human skin owing to their beneficial biologic functions, including the antiwrinkle effect and the inhibition of skin problems, for food or cosmetic compositions.
Article
Twenty-eight tetraketones (1-28) with variable substituents at C-7 were synthesized and evaluated as tyrosinase inhibitors. Remarkably compounds 25 (IC(50)=2.06 microM), 11 (IC(50)=2.09 microM), 15 (IC(50)=2.61 microM), and 27 (IC(50)=3.19 microM) were found to be the most active compounds of the series, even better than both standards kojic acid (IC(50)=16.67 microM) and L-mimosine (IC(50)=3.68 microM). This study may lead to the discovery of therapeutically potent agents against clinically very important dermatological disorders including hyperpigmentation as well as skin melanoma.
Article
5-Lipoxygenase (5-LO) catalyzes the conversion of arachidonic acid (AA) into leukotriene (LT) A(4) and 5-hydroperoxyeicosatetraenoic acid. LTA(4) can then be converted into LTB(4) by LTA(4) hydrolase or into LTC(4) by LTC(4) synthase and the LTC(4) synthase isoenzymes MGST2 and MGST3. LTB(4) is a potent chemoattractant for neutrophils, eosinophils and monocytes leading to adherence of phagocytes to vessel walls, neutrophil degranulation and release of superoxide anions. LTC(4) and its metabolite, LTD(4), are potent bronchoconstrictors that increase vascular permeability and stimulate mucus secretion from airways. Recent data also suggest that LT have an immunomodulatory role. Due to these properties, the increased biosynthesis of LT in asthma, and based upon clinical data obtained with CysLT(1) receptor antagonists in asthma patients, there is a consensus that CysLT play a prominent role in asthma. In this review, we summarize the knowledge on possible functions of the 5-LO pathway in various diseases like asthma, cancer and cardiovascular events and review the corresponding potential therapeutic roles of 5-LO inhibitors.
Article
The scavenger activities of Equisetum arvense, Equisetum ramosissimum and Equisetum telmateia aboveground parts phosphate buffer (pH 7) extracts were evaluated using three different methods: DPPH assay, ESR and NO radical inhibition assay. Total reducing power was determined by FRAP assay. The E. telmateia extract demonstrated the most relevant scavenger and antioxidant properties. ESR signal of DMPO-OH radical adducts in the presence of E. telmateia phosphate buffer (pH 7) extract was reduced to 98.9% which indicated that E. telmateia could be a useful source of antioxidants with huge scavenger ability.
Article
Degradation of elastin, the main amorphous component of elastic fibers, by elastases belonging to the serine, metallo, or cysteine families leads to the generation of elastin fragments, designated as elastokines in keeping with their cytokine-like properties. Generation of elastokines from one of the longest lived protein in human might represent a strong tissue repair signal. Indeed, they (1) exhibit potent chemotactic activity for leukocytes, (2) stimulate fibroblast and smooth muscle cell proliferation, and (3) display proangiogenic activity as potent as VEGF. However, continuous exposure of cells to these matrikines, through increased elastase(s) expression with age, can contribute to the formation of a chronic inflammatory state, that is, inflamm-aging. Importantly, binding of elastokines to S-Gal, their cognate receptor, proved to stimulate matrix metalloproteinase expression in normal and cancer cells. Besides, these elastin fragments can polarize lymphocytes toward a Th-1 response or induce an osteogenic response in smooth muscle cells, and arterial wall calcification. In this chapter, emphasis will be made on the contribution of elastokines on the genesis of age-related arterial wall diseases, particularly abdominal aortic aneurysms (AAAs). An elastokine theory of AAAs progression will be proposed. Age is one main risk factor of cancer incidence and development. The myriad of biological effects exerted by elastokines on stromal and inflammatory cells led us to hypothesize that they might be main actors in elaborating a favorable cancerization field in melanoma; for instance these peptides could catalyze the vertical growth phase transition in melanoma through increased expression of gelatinase A and membrane-type 1 matrix metalloproteinase.