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Investigational study of Juglans regia extract and quercetin against photoaging
Abstract
Walnut contains different polyphenolic compounds with antioxidant activities, and it has long been known for its diverse pharmacological activities. However, anti-aging and anti-inflammatory effects of these have not been investigated. The objective of this work was to investigate the ability of Juglans regia kernels to protect mice skin against ultraviolet (UV) radiations-induced damage in vivo. To study the effect of walnut on collagen, the skin of mice was treated with 5% w/w of ethanolic extract of walnut over 12 weeks. The physical parameters, like wrinkle assessment, biochemical parameters evaluation viz. collagen levels, TBARS, GSH, etc. and histological parameters’ evaluations were performed. Conversely, the extract was not able to revive morphological normality of skin, as compared to the standard group (quercetin treated). Histopathological studies confirmed increased protection of the skin by quercetin treatment, rather than crude extract. The extract may owe its protective effect by the extract due to the MMP-1 inhibition in addition to the suppression of MIP-α, thus, downregulating the inflammatory response.
... It is also a good source of flavonoids, sterols, pectic substances, phenolic acids and related polyphenols [14,15]. It is reported that J. regia inhibits oxidative damages [16], inflammation [17], tumor growth [18] and photoaging [19]. Recently, we reported that male flower of J. regia L. (MEJR) has showed several active molecules and it prevents UVB radiation induced inflammation in HaCaT cells [20,21]. ...
... Several studies have been documented that polyphenol-rich extracts of different plant extracts prevented skin cells from UVB-induced photoaging through inhibiting the MMPs and MAPKs expression [43][44][45]. Moreover, ethanolic extract of J. regia L. kernels has the capacity to downregulate the photoaging responses by suppressing the MMPs [19]. This property of the extract could be directly linked to its antioxidant property. ...
Solar ultraviolet-B radiation (UVB) has severe adverse effects on the structure and functions of the skin. Although, UVB (290-320 nm) represents only 5-10% of UV light reaching earth's surface, its contribution towards photoaging is tremendous. In this present study was investigate the photoprotective effect of methanolic extract of the male flower of J. regia L. (MEJR) against UVB induced photoaging in human epidermal kerati-nocytes (HaCaT). Cells were exposed to UVB-irradiation at a dose of 20 mJ/cm 2 , induces the activation of several signaling pathways which are associated with oxidative stress and photoaging. A single dose of UVB irradiation increased the protein and mRNA expression of MAPKs, AP-1, MMPs, Smad7 and decreased expression of TIMP-1/2, TGF-β1, Smad3, procollagen type-1 in HaCaT cells. In contrast, pretreatment of MEJR (80 μg/ml) prior to UVB-irradiation significantly prevented the overexpression of MAPKs, AP-1, MMPs, Smad7 and decreased expression of TIMP-1/2, TGF-β1, Smad3 and procollagen type-1 in HaCaT cells. Moreover, pretreatment of MEJR (80 μg/ml) prior to UVB-irradiation significantly prevents apoptosis in sub G o-phase. Thus, MEJR protects UVB-mediated photoaging in human skin cells, by modulating the expression of photoaging markers. The protection might be because of the presence of the good amount of bioactive compounds in MEJR.
... E.: Antioxidant (Acetone E., highest), concentration dependent growth inhibition activity by DPPH assay, and cytotoxic agains Colo205 cell lines (Aq. E.) [293], c) 95% MeOH E. (bark): Antimicrobial, synergistic activity with oxacillin against MRSA by agar dilution and microbroth dilution tests (in vitro) [294], d) Dec., and MeOH E., (Procyanidins and taxifolin derivatives, and tocopherols) (leaves): Antitumor on hepatocellular carcinoma (HeLa cell lines), nontoxic on liver normal cells, antioxidant on DPPH, βcarotenbleaching inhibition, reducing power, and thiobarbituric acid reactive substances tests [295], e) 100 mg leave E. (Capsule), two times a day for three months: Effective on HbA1c, cholesterol, triglyceride levels, and cardioprotective [296], f) 80% EtOH, quercetin: Protective against UV solar rays, antiaging [297], g) EtOH E.: ...
The increase of challenges in people's lives, daily problems as well as traumatic events could lead them to experience stress. Because of the side effects of current drugs, the recent medications are not sufficient to cure stress-related diseases; new approaches are needed in order to find more effective medications with fewer sideeffects. Ethnobotanical and ethnomedical research is increasingly recognized as a viable source of data and plausible pharmacological action of many plants. The review presents ethnobotanical information of the plants that have been used against stress-related diseases among local people of Turkey. In addition, a survey of the current literature on the topic aims to find new natural resources that will contribute to the development of drugs and bring them to the literature by scanning the scientific articles on the isolation and structure determination of the secondary metabolites of these medicinal plants, which have been already in use among the public for stressrelated disorders for centuries. This research is not only the first step in the research of promising new compounds against stress but it is also a presentation of data on medicinal plants of Turkey: Their medicinal parts, method of preparation, usage patterns and, if recorded, their dosages.
... There are some other phytochemicals and crude extracts of certain plants that have been reported for other activities. Some of them are hesperidin (Habibyar et al. 2016), boswellic acid (Mehta et al. 2018), gallic acid (Pandey et al. 2015;Manshare et al. 2018), quercetin (Singh Joshan and Singh 2013;Chellappan et al. 2019), sinomenium (Gupta et al. 2019), curcumin Garg et al., 2019;Som et al. 2020), Artemisi indica (Nahid et al. 2017), Plumbago auriculata (Jaryal and Kaur 2017), and Withania somnifera (Jassal and Kaur 2016). Fisetin (FS) is a bioactive polyphenolic flavonoid also known as 3, 7, 3', 4'-tetrahydroxy flavone. ...
Fisetin is a polyphenolic flavonoid reported to have antioxidant, anti-inflammatory, and anti-cancer activities. However, it loses its importance as an effective phytochemical due to its poor water solubility and lower bioavailability. In the present study, the self-nanoemulsifying drug delivery system (SNEDDS) of fisetin was developed in order to improve its pharmacological activity. The developed SNEDDS of fisetin was evaluated for improving the rotenone-induced behavioral changes in the rats, and its efficacy was compared with naïve fisetin. It was noticed that fisetin loaded in the SNEDDS formulation significantly (p < 0.001) ameliorated the rotenone-induced alteration in the body weight, grip strength, beam walk, postural instability, etc., in rats when compared to the effect of naïve fisetin. Naïve fisetin significantly (p < 0.05) ameliorated the effect of rotenone on the level of dopamine only at a higher dose. Whereas, SNEDDS of fisetin produced a significant (p < 0.05) effect at both dose levels when compared with the diseased group as well as also produced a significant (p < 0.05) effect when compared with the naïve fisetin group. The results of histopathological examination revealed about the neuroprotective effect of SNEDDS loaded with fisetin as observed through the protection of neuronal damage. From this study, it was concluded that SNEDDS improved the anti-Parkinsonian activity of fisetin by improving the behavioral alteration produced by rotenone due to enhancement in its solubility and bioavailability.
... J. regia bitkisinin biyolojik aktivite açısından antioksidan, antidiyabetik, antibakteriyel, antihiperkolesterolemik olarak kullanımı, bunun yanı sıra dünyada genellikle geleneksel halk ilacı olarak özellikle yapraklarının antifungal, antihelmintik, astrenjan, keratolitik, antidiyareik, hipoglisemik, depüratif, tonik ve sinüzit tedavisinde, soğuk algınlığı, karın ağrısı ve yanıklarda kullanımı, meyvesinin, özellikle Çin tıbbında tonik olarak "anti-aging" amaçlı kullanımı, hemoroid ve kolesterolde yaygın olarak kullanımı dikkati çekmektedir. 22 Bu çalışmada, J. regia bitkisinden elde edilen ekstraktın C. laurentii H-9, C. laurentii H- 16 ...
... In addition to the main compounds found in coconut fiber extracts, in the present work, it was also possible to observe the presence of quercetin. The latter compound is one of the most effective antioxidants among flavonoids (Batiha et al., 2020), which has the ability to absorb UV radiation, inhibit UV-induced inflammation, in primary keratinocytes and inhibit, in animal, skin damage produced by UVB rays (Prasanth et al., 2020;Joshan and Singh, 2013;Saewan and Jimtaisong, 2013). Quercetin was also able to inhibit the glycation of HSA (Human Serum Albumin) in the initial and intermediate stages (Ashraf et al., 2015), as well as significantly reducing the hemoglobin product Amadori HbGIc, produced in the initial phase of glycation (Yeh et al., 2017). ...
Underutilized parts of some abundant crops can be valuable and the search for additional uses, mainly in healthy and for social purposes are very attractive. This is the case of Cocos nucifera Linn., an important source of phenolic compounds and a native plant of tropical countries, widely distributed in the Northeast and North of Brazil. The objectives of this study were to determine the phenolic chemical composition, the photoprotection capacity, represented by sun protector factor (SPF), of the ethanol extract of coconut (Cocos nucifera) husk fiber of the yellow dwarf variety (EEYD) against UVB rays and after its incorporation into sunscreen formulations. Antiglycation activity [represented by bovine serum albumin (BSA) – glucose/fructose, Collagen – glucose/fructose and BSA-Methylglyoxal (MG) assays], using aminoguanidine (AG) as a positive control, and cytotoxic effects toward macrophages, were also evaluated. The identification of non-toxic antiglycation agents holds great promise in the development of alternative therapies for diseases, such as diabetes and their complications and is not often, reported in the literature. The determination of the SPF of the EEYD together with its sunscreen formulations was performed by in vitro method. A total of seven phenolic compounds, quercetin, catechin, epicatechin, vanillic, caffeic, 4-hydroxybenzoic and chlorogenic acids were identified by high performance liquid chromatography (HPLC)-UV/Vis and ultra high performance liquid chromatography - tandem mass spectrometer UHPLC-MS/MS. The present extract (EEYD) presented photoprotective activity with SPF values equivalent to the standards, benzophenone-3 and quercetin. The formulations prepared in different concentrations of the extract (5–20 % w/w) showed maximum SPF values of 15.94. The extract presented promising antiglycation activity, higher than the positive control, the pure compound aminoguanidine (AG), except for BSA/MG, with values for BSA/glucose/fructose of 9.61 μg/mL (vs.AG 18.30 μg/mL); for collagen/glucose/fructose of 4.50 μg/mL (vs.AG 82.87 μg/mL) and 34.76 μg/mL (vs.AG,13.19 μg/mL). The present ethanol extract does not decrease macrophage viability and presents a plethora of biologically active compounds. The combined results have shown the possibility of using non-toxic EEYD, as an active ingredient in sunscreen formulations and in the nutrition/medicinal areas, giving extra value to an environmental-unfriendly residue, with strong prospects for success.
... 25,26 Furthermore, previous studies indicated that walnut polyphenols have a stronger antioxidant action than nonpolar antioxidants present in the lipid fraction, such as tocopherols and tocotrienols, making them the main compounds responsible for the antiradical protection provided by walnuts. 16,27 The results of a series of studies 14,28 suggested that the antioxidant activities of phenolic compounds isolated and identified from kernels of J. regia may be influenced by the number of hydroxyls in their aromatic rings. The structureactivity relationship evaluation of these phenolic compounds suggested that the number of hydroxyls was the most important factor in determining the antioxidant activities of the phenolic compounds; in addition, it was suggested that the potency of these compounds could provide a chemical basis for some of the health benefits claimed for J. semen in foods and folk medicine. ...
In this study, the chemical composition of Juglandis semen extracts obtained by different extraction solvents and methods, were determined by Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The multivariate analyses: principal component analysis, k-means clustering and hierarchical cluster analysis of the FTIR and Raman spectral data set was performed to determine the differences in the chemical composition according to the solvent (e.g. mixture of water with alcohol, glycerin and propylene glycol) and the extraction method (i.e. ultrasound-assisted extraction, rapid pressurized extraction and subcritical fluid extraction). The obtained results reveal that the Juglandis semen extracts with water-alcohol solvent have equivalent chemical composition. A well-defined differentiation based on extraction method could not be highlighted. Based on FTIR data compilation it can be observed that a first classification can be made based on the solvent, acidic or basic used for extraction methods (excepting subcritical fluid extraction - SFE, clustering is clearly assigned by the solvent used). Multivariate analysis (i.e. k-means Clustering followed by AHC) on Raman spectroscopy was able to differentiate SFE extract as a unique cluster, that means HFC134a solvent allowed a specific extraction (from organic constituents point of view) due to the selected conditions of extraction method.
... Bhatia et al. (2006) also reported that J. regia L. bark could restore the antioxidant status and prevent lipid peroxidation in case of urotoxicity induced by cyclophosphamide in mice. Joshan and Singh, (2013) reported that J. regia could increase the level of antioxidant enzymes, including SOD and CAT in CCl 4 treated animal model. The evidence emerged during the present study clearly indicate the possibility of restoration of antioxidant activity and inhibition of lipid peroxidation by MEJR due to its free radical scavenging property. ...
... It is also a good source of flavonoids, sterols, pectic substances, phenolic acids and related polyphenols (Shah et al., 2014). The extracts from J. regia L. inhibit oxidative damages (Zhao et al., 2014), inflammation (Hosseinzadeh et al., 2011), tumor growth (Negi et al., 2011) and photo-aging (Joshan and Singh, 2013). In this study, we screened selected dietary flavonoids from J. regia L. (Article in press) such as pantothenic acid (vitamin B5); 3,4,5-trihydroxy benzoic acid (gallic acid); madecassic acid and hexadecanoic acid, ethyl ester (palmitic acid) for their binding interaction with p53 by induced-fit docking. ...
The p53 tumor suppressor acts to integrate multiple stress signals into a series of diverse antiproliferative responses. One of the most important functions of p53 is to activate apoptosis. Disruption of this process can promote tumor progression and chemoresistance. It apparently promotes apoptosis through transcription-dependent and transcription-independent mechanisms that act in concert to ensure that the cell death program proceeds efficiently. Moreover, the apoptotic activity of p53 is strictly controlled, and influenced by a series of quantitative and qualitative events that ultimately determine the outcome of p53 activation. Naturally occurring plant derived compounds are considered as attractive candidates for cancer treatment and prevention. Phytoconstituents can control and modify various biological activities by interacting with molecules involved in various signaling pathways. In this study, induced fit docking was carried out for understanding the binding interactions of Juglans regia L. derived pantothenic acid (vitamin B5); 3,4,5-trihydroxy benzoic acid (gallic acid); madecassic acid and hexadecanoic acid, ethyl ester (palmitic acid) with p53. Favorable binding conformations between p53 and the four phytoconstituents were observed. A number of poses were generated and evaluated for understanding binding conformations and common interacting residues between ligands and proteins and the best ligands against 140 | P a g e p53 are reported. They may be used as potential inhibitors of carcinogenesis by targeting p53 dependent pathway. Further studies need to be carried out to explore the pharmacological properties and inhibitory potentials of these flavonoids in experimental models.
... [6] The extracts from J. regia nut inhibited oxidative damages, [7][8][9][10] inflammation, [11,12] tumor growth, [8,13] antiwrinkle, and photoageing. [14] Kernels as a dietary food, against diabetes, hypoxia, some skin diseases, and inflammation [15,16] ; leaves as antidiarrheals, anthelmintic, depurative [17] and also mixed with stored-grains as an insecticide and fungicide. [17,18] Stem bark as an astringent, anthelmintic, depurative, bactericide, diuretic, digestive, laxative, stimulant, detergent, and insecticidal. ...
The male flower of Juglans regia L., were investigated for its in vitro antioxidant activity, antimicrobial activity, and chemical constituents. The antioxidant activity showed that the methanol extract of J. regia male flower (MEJR) had highest scavenging potential than the other solvents (ethanolic = EEJR and aqueous = AEJR). The antimicrobial activity showed that Staphylococcus aureus and Escherichia coli were the most sensitive organisms and significant activity was also recorded against both the fungal strains tested, with highest activity against Candida albicans. Totally, 26 constituents were identified by high-resolution-liquid chromatography-mass spectrometry analyses from which seven compounds were identified first time from the extract.
... Quercetin also showed to reduce photoaging. Topical application of 1% quercetin on female albino mice exposed to an UV dose over a twelve-week increased skin moisture content, reduced thiobarbituric acid reacting substances, reduced glutathione increased with a diminution of wrinkles in number and depth (Singh Joshan and Singh 2013). ...
... also reported that J. regia L. bark could restore the antioxidant status and prevent lipid peroxidation in case of by cyclophosphamide in mice.Joshan and Singh, (2013) reported that J. regia could increase the level of antioxidant enzymes, including SOD and CAT in CCl 4 treated animal model. The evidence emerged during the present study clearly indicate the possibility of restoration of antioxidant activity and inhibition of lipid peroxidation by MEJR due to its free radical scavenging property. ...
Background:
Juglans regia L. has a history of traditional medicinal use for the treatment of various maladies and have been documented with significant antioxidant and antiinflammatory properties. Although all parts of the plant are medicinally important, but male the flower of the plant has not been yet investigated against the photo-damage.
Purpose:
The present study, we sought to determine the photoprotective effect of the male flower of J. regia L. against ultraviolet-B radiation-induced inflammatory responses in human skin cells.
Methods:
The profile of pharmacological active compounds present in the male flower of J. regia was analyzed by GC-MS. Then, the antioxidant property of methanolic extract of J. regia (MEJR) was analyzed by in vitro free radical scavenging assays. Further, we analyzed the sun protection factor of this extract by spectrophotometry. Moreover, we investigated the photoprotective effect of MEJR against UVB induced inflammatory signaling in human epidermal cells. Human skin epidermal keratinocytes (HaCaT) were pretreated with the MEJR (80 µg/ml), 30 min prior to UVB-irradiation at a dose of 20 mJ/cm2 and were investigated for lipid peroxidation, enzymatic antioxidants activity, apoptosis and inflammatory markers expression level.
Results:
The GC-MS results showed the presence of good amount of pharmacologically active compounds in the MEJR. We observed that the MEJR possess significant free radical scavenging activity and it was comparable with standard antioxidants. Further, the MEJR exhibits 8.8 sun-protection-factor (SPF) value. Pretreatment with MEJR, 30 min prior to UVB-irradiation, prevented ROS generation, lipid peroxidation and restored the activity of antioxidant status in HaCaT cells. Moreover, MEJR pretreatment significantly prevented UVB activated inflammatory markers like TNF-α, IL-1, IL-6, NF-κB, COX-2 in HaCaT.
Conclusion:
The present findings suggest that MEJR exhibit photoprotective effects and hence it may be useful for the treatment of inflammation related responses. The pharmacological mechanism of MEJR partly associated with its UV absorbance, modulation of inflammatory signaling as well as due to its free radical scavenging capability.
... Quercetin also holds great promise for topical application, as it shows strong protective effect against UVinduced lipid peroxidation [27] and proved to be effective on human keratinocytes with anti-ageing activity and skin rejuvenation capability [28]. Quercetin, dissolved in a mixture of ethanol, propylene glycol and water, was applied topically on hairless mice before the exposure to UV irradiation and showed wrinkle diminishing ability and an increase in collagen content with an increase in glutathione and a decrease in thiobarbituric acid reactive substances [29]. However, because quercetin possesses a poor water solubility, instability and very low skin permeability in its crude form [30], the development of adapted formulations should be investigated in order to deliver the effective dose of quercetin to skin tissue (epidermis). ...
Quercetin is a plant flavonoid with strong antioxidant and antiinflammatory properties interesting for skin protection. However, its poor water solubility limits its penetration and so its efficiency on skin. For this purpose, quercetin lipid nanocapsules were formulated implementing phase inversion technique wherein several modifications were introduced to enhance quercetin loading. Quercetin lipid nanocapsules were formulated with two particle size range, (50 nm and 20 nm) allowing a drug loading of 18.6 and 32 mM respectively. The successful encapsulation of quercetin within lipid nanocapsules increased its apparent water solubility by more than 5,000 fold (from 0.5 μg/ml to about 5 mg/ml). The physicochemical properties of these formulations such as surface charge, stability and morphology were characterized. Lipid nanocapsules had spherical shape and were stable for 28 days at 25 °C. Quercetin release from lipid nanocapsules was studied and revealed a prolonged release kinetics during 24 h. Using DPPH assay, we demonstrated that the formulation process of lipid nanocapsules did not modify the antioxidant activity of quercetin in vitro (92.3%). With the goal of a future dermal application, quercetin lipid nanocapsules were applied to THP-1 monocytes and proved the cellular safety of the formulation up to 2 μg/ml of quercetin. Finally, formulated quercetin was as efficient as the crude form in the protection of THP-1 cells from oxidative stress by exogenous hydrogen peroxide. With its lipophilic nature and occlusive effect on skin, lipid nanocapsules present a promising strategy to deliver quercetin to skin tissue and can be of value for other poorly water soluble drug candidates.
... Quercetin inhibition of matrix metalloproteinase activity may also show a role in protection of skin collagen from destruction during inflammatory response to extrinsic aging factors [66,67]. In an in vivo study, Joshan et al. [44] tested quercetin protective activity against photoaging on female albino mice. Mice dorsal skin was exposed to an UV dose of 0.036-0.216 ...
Skin is a multifunctional organ with activities in protection, metabolism and regulation. Skin is in a continuous exposure to oxidizing agents and inflammogens from the sun and from the contact with the environment. These agents may overload the skin auto-defense capacity. To strengthen skin defense mechanisms against oxidation and inflammation, supplementation of exogenous antioxidants is a promising strategy. Quercetin is a flavonoid with very pronounced effective antioxidant and antiinflammatory activities, and thus a candidate of first choice for such skin supplementation. Quercetin showed interesting actions in cellular and animal based models, ranging from protecting cells from UV irradiation to support skin regeneration in wound healing. However, due to its poor solubility, quercetin has limited skin penetration ability, and various formulation approaches were taken to increase its dermal penetration. In this article, the quercetin antioxidant and antiinflammatory activities in wound healing and supporting skin against aging are discussed in detail. In addition, quercetin topical formulations from conventional emulsions to novel nanoformulations in terms of skin penetration enhancement are also presented. This article gives a comprehensive review of quercetin for topical application from biological effects to pharmaceutical formulation design for the last 25 years of research.
Quercetin is abundant in plants and has notable pharmacological properties for skin health. This review aims to comprehensively evaluate the effects of quercetin on skin-related issues, adhering to the PRISMA guidelines and analyzing studies from ScienceDirect, Web of Science, Scopus, and PubMed. Of the 1,398 studies identified, 65 studies met the criteria for meta-analysis. The meta-analysis indicated that quercetin had powerful antioxidant properties, protecting against oxidative stress by significantly lowering levels of MDA (Z-score, 2.51), ROS (Z-score, 3.81), and LPO (Z-score, 4.46), and enhancing enzymes of GSH (Z-score, 5.46), CAT (Z-score, 5.20), and SOD (Z-score, 4.37). Quercetin acted as an anti-inflammatory by significantly suppressing protein regulators such as NF-κβ, AP-1, and MAPKs (ERK and JNK), cytokines of TNFα, IL-6, IL-1β, IL-8, and MCP-1, and enzymes of COX-2, iNOS, and MPO, while upregulating the cytokine IL-10. Additionally, quercetin significantly suppressed IL-4 (Z-score, 3.16) and IFNγ (Z-score, 3.76) cytokines involved in chronic inflammation of atopic dermatitis. Quercetin also supported wound healing by significantly decreasing inflammatory cells (Z-score, 5.60) and enhancing fibroblast distribution (Z-score, 5.98), epithelialization (Z-score, 8.57), collagen production (Z-score, 4.20), and angiogenesis factors of MVD (Z-score, 5.66) and VEGF (Z-score, 3.86). Furthermore, quercetin significantly inhibited tyrosinase activity (Z-score, 1.95), resulting in a significantly reduced melanin content (Z-score, 2.56). A significant reduction in DNA damage (Z-score, 3.27), melanoma cell viability (Z-score, 2.97), and tumor formation was also observed to ensure the promising activity of quercetin for skin issues. This review highlights quercetin's potential as a multifaceted agent in skin care and treatment.
Graphical abstract
The cosmetic industry is constantly searching for bioactive ingredients, namely, those obtained from natural sources with environmentally friendly connotations and less toxic effects. A previous study of our research group optimized the extraction of phenolic compounds from Juglans regia by heat-assisted extraction. Due to its richness in different phenolic compounds, the present work aimed to develop a formulation containing J. regia leaf extract. The extract’s antioxidant, anti-tyrosinase, antimicrobial, anti-inflammatory, wound healing, cytotoxicity, and photostability properties were evaluated. The extract was then incorporated into an O/W base cream, followed by characterization of the final formulation in terms of its antioxidant properties, phenolic composition, and stability over time and at different storage conditions. The most abundant compounds in the hydroethanolic extract were 3-O-caffeoylquinic acid (18.30 ± 0.04 mg/g), quercetin-O-pentoside (9.64 ± 0.06 mg/g), and quercetin 3-O-glucoside (6.70 ± 0.19 mg/g). Besides those, the extract presented antioxidant, anti-inflammatory, wound closure, and antibacterial effects against several skin pathogens. In addition, HaCaT cell viability was maintained up to 98% at 400 µg/mL. Within Proteus vulgaris-infected HaCaT cells, the extract also presented an over 40% bacterial mortality rate at its nontoxic concentration (200 µg/mL). After incorporating the extract, the obtained formulation presented a good physicochemical profile over time and at different storage conditions while also maintaining its antioxidant effect; as such, it can be considered stable for topical application. Future work to evaluate its performance in terms of skin permeation and detailed toxicological studies with a focus on regulatory requirements, involving skin irritation, eye irritation, genotoxicity, photo-irritation, and dermal absorption, should be conducted, as the prepared formulation demonstrated relevant properties that deserve to be further explored.
The flowers of Juglans regia L. have demonstrated their medicinal value as a part of edible plants. In this study, an analytical methodology for identification of flavonoid chemical constituents in flowers of Juglans regia L. was established using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). Thirty-six flavonoid compounds were identified based on highly accurate mass measurements, and the mass spectrometric fragmentation pathways of eleven representative compounds were proposed, which was helpful for the identification of different types of flavonoids. The study has laid the foundation for the research and development of effective drugs from flowers of Juglans regia L.
Exposure to UV light triggers the rapid generation and accumulation of reactive oxygen species (ROS) in skin cells, with consequent increase in oxidative stress and thus in photoaging. Exogenous supplementation with dietary antioxidants and/or skin pretreatment with antioxidant-based lotions before sun exposure might be a winning strategy against age-related skin pathologies. In this context, plants produce many secondary metabolites to protect themselves from UV radiations and these compounds can also protect the skin from photoaging. Phenolic compounds, ascorbic acid and carotenoids, derived from different plant species, are able to protect the skin by preventing UV penetration, reducing inflammation and oxidative stress, and influencing several survival signalling pathways. In this review, we focus our attention on the double role of oxidants in cell metabolism and on environmental and xenobiotic agents involved in skin photoaging. Moreover, we discuss the protective role of dietary antioxidants from fruits and vegetables and report their antiaging properties related to the reduction of oxidative stress pathways.
Flavonoids are plants pigments. Flavonoids can be observed by the naked eye as they form the amazing colors of flower petals. Flavonoids are classified on the basis of their chemical structure composed of two aromatic cycles connected by three carbons: C6-C3-C6, chains are closed in hexa- or pentagonal oxygenated heterocyclic ring. Flavonoids present interesting physiological activates that permit their usefulness as medicaments, especially for their free radical scavenging ability. Indeed, flavonoids activates were the object of numerous review articles.Among flavonoids, quercetin is the molecule the most distributed in nature that presents the strongest antioxidant and antiinflammatory activities in comparison to other molecules of this family. In general flavonoids and specially quercetin present poor water solubility, thus limiting their absorption/penetration and as a result their efficiency.Starting for the idea that the skin is the largest organ of the human body and the organ, which the most exposed to oxidative stress due to UV irradiation or other corrosive and irritating chemicals. Quercetin is a candidate for skin supplementation with exogenous antioxidant. The first objective of the thesis is to develop several formulations at the nanometric range for quercetin, in order to increase its water solubility and to enhance its physicochemical properties. The second objective is to compare these formulations in terms of quercetin loading capacity, cellular toxicity of quercetin and its formulations on HaCaT cells (keratinocytes), THP-1 cells (monocytes) and Vero cells (epithelial). Then, the protective activity of quercetin in vitro on cells to finally put in evidence the increase of quercetin in vivo skin penetration in formulations.In this project, three nanoformulations approaches (smartCrystals®, lipid nanocapsules and liposomes) were tested for the increase of quercetin water solubility. The formulations were optimized for scale up to industrial scale at the level of preparation method, also in the excipients compositions for higher affinity to quercetin. The formulations were characterized in terms of particle size, PDI, quercetin loading, crystallinity evaluation and quercetin in vitro release profile. Then, formulations were compared in interaction with HaCaT and THP-1 cells for their cellular toxicity and protective activity. Finally, two formulations (quercetin smartCrystals® with TPGS and quercetin lipid nanocapsules 20) were selected and compared for the enhancement of the in vivo skin penetration of quercetin.This project propose a solution for the successful formulation of quercetin enabling its efficient skin delivery. This project can be extrapolated to industrial level for quercetin and other poorly water soluble molecules that present limited efficiency due to their low skin penetration capacity.
The medicinal plants have been selected for thorough studies from indigenous folk medicines, Ayurvedic, Unani and Siddha systems of medicines. The aim of this study deals with the comparative evaluation of anti-inflammatory activity of the bark of Ficus bengalensis in plants of different age. The anti-inflammatory activity was evaluated by rat paw edema model induced by carrageenan for acute inflammation and cotton pellet granuloma model for chronic inflammation. Indomethacin was used as a standard drug. The various extracts were studied for their anti-inflammatory activity in carrageenan-induced hind paw edema in rats and the paw volume was measured plethysmometrically from 0 to 3h after injection. We have determined the anti-inflammatory activity of various extracts of the bark of Ficus bengalensis with oral administration doses of 300 and 600 mg/kg/day of body weight to healthy animals. Positive results for flavonoids, sterols, and triterpene, tannins and saponins compounds were investigated by phytochemical analysis. The ethanolic extract of younger plant showed a greater anti-inflammatory effect compared with the standard drug indomethacin. Present studies besides confirming anti-inflammatory activity of the ethanolic extract of younger more potent than mature plant help to identify from the comparative study of the bark of Ficus bengalensis.
shown that UVA can induce epidermal tumours (6), and contributes to erythe- ma caused by solar exposure (7).
Objective
To search for new sources of safe and inexpensive antioxidants, the leaf, root and rhizome of Enhalusacoroides (E. acoroides) were screened for the first time for their antioxidantactivities.
Methods
Samples of leaf, root and rhizome from E. acoroides were tested for total phenolic content, proanthocyanidins and in vitroantioxidantactivity in terms of total antioxidant assay, DPPH assay and FRAP assay.
Results
The leaf sample was found to have high levels of phenolic (0.323±0.028 mg TAE/g) and proanthocyanidins (0.570 0±0.000 3 mg TAE/g) when compared to root and rhizome. The leaf samples exhibited higher total antioxidantactivity (11.770±0.026 mg Ascorbic acid equivalent/g), higher percentage of DPPH radical scavenging activity (25.76±0.04) and higher reducing power (18.060±0.073) in terms of mg GAE/g. In addition, there was a significant correlation between total phenolic content and total antioxidantactivity (R2=0.923), DPPH assay (R2=0.509), FRAP assay (R2=0.994). Similarly, significant correlation was found between the proanthocyanidin and total antioxidantactivity (R2=0.977), DPPH assay (R2=0.464) and the FRAP assay (R2=0.998).
Conclusion
These results suggested that E. acoroides have strong antioxidant potential. Further study is necessary for isolation and characterization of the active antioxidant agents, which can be used to treat various oxidative stress-related diseases.
Polyphenols are the biggest group of phytochemicals, and many of them have been found in plant-based foods. Polyphenol-rich diets have been linked to many health benefits. This paper is intended to review the chemistry and biochemistry of polyphenols as related to classification, extraction, separation and analytical methods, their occurrence and biosynthesis in plants, and the biological activities and implications in human health. The discussions are focused on important and most recent advances in the above aspects, and challenges are identified for future research.
The purpose of this study was to develop an improved method for collagen and protein assessment of fibrotic lungs while decreasing animal use.
8-10 week old, male C57BL/6 mice were given a single intratracheal instillation of crocidolite asbestos or control titanium dioxide. Lungs were collected on day 14 and dried as whole lung, or homogenized in CHAPS buffer, for hydroxyproline analysis. Insoluble and salt-soluble collagen content was also determined in lung homogenates using a modified Sirius red colorimetric 96-well plate assay.
The hydroxyproline assay showed significant increases in collagen content in the lungs of asbestos-treated mice. Identical results were present between collagen content determined on dried whole lung or whole lung homogenates. The Sirius red plate assay showed a significant increase in collagen content in lung homogenates however, this assay grossly over-estimated the total amount of collagen and underestimated changes between control and fibrotic lungs, conclusions: The proposed method provides accurate quantification of collagen content in whole lungs and additional homogenate samples for biochemical analysis from a single animal. The Sirius-red colorimetric plate assay provides a complementary method for determination of the relative changes in lung collagen but the values tend to overestimate absolute values obtained by the gold standard hydroxyproline assay and underestimate the overall fibrotic injury.
Acute ultraviolet (UV)-B irradiation causes skin wrinkle formation associated with hyperplasia of cutaneous blood vessels. This study reports that increased dermal oxygen tension attenuates acute UVB-induced angiogenesis and wrinkle formation. Twenty-four hairless mice (HOS:HR-1) were assigned to 3 groups: 1) control group, 2) UVB-irradiated (UVB) group, and 3) UVB-irradiated and hyperoxia-exposed (UVB+HO) group. The backs of the mice were exposed to UVB irradiation 3 times per week for a 5-wk period. To increase dermal oxygen tension, the mice were exposed to hyperoxia (90% oxygen) for 2 h immediately after each UVB irradiation. Hyperoxic exposure increased dermal oxygen tension by about 10 times compared with the control level. Degree of wrinkle formation and epidermal thickness increased significantly after a 5-wk UVB-irradiation period, whereas hyperoxic exposure attenuated these increases. Tissue adenosine triphosphate concentration and angiogenesis increased significantly only in the UVB group compared with the control group. Although the expression of hypoxia inducible factor-1alpha mRNA, a key molecule for angiogenesis, increased significantly in the UVB and UVB+HO groups compared with the control group, the protein level increased significantly only in the UVB group. The activity of matrix metalloproteinase-2 and -9, critical molecules for angiogenesis, did not increase in the UVB and UVB+HO groups compared with the control group. Active type 1 collagenase activity and soluble collagen content in all of the groups were roughly similar. These results suggest that increased dermal oxygen tension attenuates angiogenesis and wrinkle formation following acute UVB irradiation.
Growth of tumors and metastasis are processes known to require neovascularization. To ascertain the participation of the endogenous angiogenic inhibitor thrombospondin-1 (TSP1) in tumor progression, we generated mammary tumor-prone mice that either lack, or specifically overexpress, TSP1 in the mammary gland. Tumor burden and vasculature were significantly increased in TSP1-deficient animals, and capillaries within the tumor appeared distended and sinusoidal. In contrast, TSP1 overexpressors showed delayed tumor growth or lacked frank tumor development (20% of animals); tumor capillaries showed reduced diameter and were less frequent. Interestingly, absence of TSP1 resulted in increased association of vascular endothelial growth factor (VEGF) with its receptor VEGFR2 and higher levels of active matrix metalloproteinase-9 (MMP9), a molecule previously shown to facilitate both angiogenesis and tumor invasion. In vitro, enzymatic activation of proMMP9 was suppressed by TSP1. Together these results argue for a protective role of endogenous inhibitors of angiogenesis in tumor growth and implicate TSP1 in the in vivo regulation of metalloproteinase-9 activation and VEGF signaling.
The aim of this chapter is to describe algorithms for estimating the amount of solar energy incident at ground level on horizontal and inclined surfaces as well as on sun tracking surfaces. First, a general algorithm for estimating the solar irradiation on tilted surfaces is summarized. Next, models are presented for, respectively, the calculation of extraterrestrial radiation, quantification of the atmosphere effect on extraterrestrial solar radiation, calculation of solar irradiance on the horizontal plane, and transposing the result on tilted planes. Some of these models may be included within the procedures for forecasting the solar resource. Simple models may be used for straightforward prediction of solar irradiance and irradiation on horizontal surface under clear sky conditions. For more demanding applications, parametric models are the alternative. Basically, this is feasible by employing forecasted meteorological parameters as model inputs. For adjusting clear sky solar irradiance to the forecasted state of the sky, a survey of the required equations is presented.
The objective of the study was to investigate the antioxidant activity of various extracts from whole plant of Bauhinia purpurea (Linn) by different in-vitro methods. Free radical assays such as iron chelating, total antioxidant activity (phosphomolybdic acid method), FRAP assay were performed. It was observed that the methanolic extract of Bauhinia purpurea (Linn) effectively scavenged free radical activity that that of other two extracts. Those antioxidant activities were compared to standard antioxidants such as ascorbate and EDTA. Our findings provide evidence that the crude methanolic extract of whole plant of Bauhinia purpurea (Linn) is a potential source of natural antioxidant, and this justified its uses in folkloric medicines.
An activity-directed fractionation and purification process was used to isolate 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging components from Juglans regia kernels. Ethyl acetate and n-butanol fractions showed greater DPPH scavenging activities compared to those of water and petroleum ether fractions. The ethyl acetate fraction was subjected to purification using column chromatography. Seven phenolic compounds, pyrogallol (1), p-hydroxybenzoic acid (2), vanillic acid (3), ethyl gallate (4), protocatechuic acid (5), gallic acid (6) and 3,4,8,9,10-pentahydroxydibenzo[b,d]pyran-6-one (7), containing significant antioxidant activities were isolated and identified in J. regia by spectroscopic methods for the first time in this study. The relative order of DPPH scavenging capacity for these compounds was 7 > 6 ⩾ 4 ⩾ 1 > Trolox ⩾ 5 > 3 > 2. The results of this study suggested that the antioxidant activities of these phenolic compounds may be influenced by the number of hydroxyls in their aromatic rings.
A water-soluble (at pH 8) aromatic disulfide [5,5'-dithiobis(2-nitrobenzoic acid)] has been synthesized and shown to be useful for determination of sulfhydryl groups. Several applications have been made to show its usefulness for biological materials. A study of the reaction of this disulfide with blood has produced some evidence for the splitting of disulfide bonds by reduced heme.
Exposure to UV radiation can cause suppression of specific immune responses. The pathways leading to the down-regulation are complex, starting from the absorption of UV photons by chromophores in the skin and ending with local and systemic changes in immune mediators, the generation of T and B regulatory cells and inhibition of effector and memory T cell activation. The consequences for human health are thought to be both beneficial and adverse. The former are illustrated by protection against polymorphic light eruption, and possible protection against T cell-mediated autoimmune diseases and asthma. The latter are illustrated by skin cancer, cutaneous lupus erythematosus and infectious diseases including vaccination. Many outstanding questions remain in this rapidly developing and controversial area, not least what advice to give the general public regarding their sun exposure. While considerable advances have been made in the development of strategies that preserve the health benefits of sunlight exposure and decrease its detrimental effects, further research is required before optimal levels of protection are achieved.
Use of in vitro tests to search for relevant activities in bark of Ficus asperifolia Miq. and leaves of Gossypium arboreum L., used in Ghana for wound healing.
Aqueous extracts of the relevant parts of the two species were tested for antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Micrococcus flavus, Escherichia coli, Pseudomonas aeruginosa and resistant strains of Staphylococcus aureus SA1199B, RN4220 and XU212. The effects of the plants on fibroblast growth stimulation as well as antioxidant protective effect against hydrogen peroxide induced damage in the same cell line were also studied.
The extracts of Gossypium arboreum and Ficus asperifolia had weak antibacterial action against all bacteria tested. The extracts of the two plants had significant (p<0.001) effects on the growth of human dermal fibroblast at 50 microg/ml and lower. They also significantly protected fibroblast cells against oxidative damage at doses up to 50 microg/ml. Gossypium arboreum leaf extract displayed the higher activity.
The stimulatory effect on fibroblast growth and protection against peroxide-induced oxidative damage give some support to the traditional use of these two plants as wound-healing agents.
Swertia chirayita, a medicinal herb endemic to the Tibetan region, is used as a special remedy for liver disorders. The hepatoprotective activity of its plant extracts has been associated with its antioxidant activity. This paper aims to investigate the in vitro and in vivo antioxidant effects of Swertia chirayita extracts (SCE).
Antioxidant ability of Swertia chirayita was investigated by employing several established in vitro methods. In vivo antioxidant activity was tested against CCl(4)-induced toxicity in mice. The levels and activities of malondialdehyde (MDA) and antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), were then assayed using standard procedures.
SCE exhibited strong antioxidant ability in vitro. The liver and kidney of CCl(4)-intoxicated animals exhibited a significant (p<0.001) decrease in SOD, CAT, and GSH levels. Additionally, these organs exhibited a significant (p<0.001) increase in MDA level. CCl(4) did not exhibit toxicity on mice treated with SCE and Vitamin E. The effects of Swertia chirayita (three dosages) were comparable to those of Vitamin E, except in MDA level in the liver and GSH level in the kidney (p<0.05).
This study suggests that the ethanolic extract of Swertia chirayita possesses in vitro and in vivo antioxidant effects. This supports the traditional use of Swertia chirayita in Tibetan medicine to cure liver diseases.
Tannins in the seed coats of cowpea cultivars interfere with the determination of lignin by the acetyl bromide method but the tannins can be removed by extraction with acetone:water (70:30) allowing a direct determination on the residue. Furthermore, the difference between the absorbance values determined by the acetyl bromide method before and after the removal of tannins can be used as a measure of tannin content in cowpea seed coats. Copyright 1995, 1999 Academic Press
Salvia species and Melissa officinalis are used for their memory-enhancing effects in European folk medicine. Teucrium polium was reported to be used in Anatolia for memory-enhancement in a very old book written by an Ottoman herbalist-physician.
Alzheimer's disease (AD) is a progressive neurological disorder mostly affecting the elder population. Currently, there is no cure for the treatment of severe type of AD. Therefore, in this study, the hydroalcoholic extracts of three traditionally used Lamiaceae species for memory-enhancement; Salvia triloba L., Melissa officinalis L., and Teucrium polium L., were assessed for their in vivo antiamnesic activity along with in vitro anticholinesterase and antioxidant activities.
Scopolamine-induced antiamnesic activity was determined in mice by passive avoidance test, while anticholinesterase effect was measured by spectrophotometric Ellman method at 0.25, 0.50, 1.0, and 2.0 mg ml(-1) and antioxidant activity was assessed by scavenging effect against 2,2-diphenylpicrylhydrazyl (DPPH). Total phenol contents of the extracts were determined by Folin-Ciocalteau method.
Salvia triloba was the most effective in antiamnesic experiment at 100, 200, and 400 mg kg(-1) doses having 22.7, 57.1, and 71.4% of relative effects, respectively. Teucrium polium was also active dose-dependently, whereas Melissa officinalis was completely inactive. In the anticholinesterase assay, the extracts showed similar inhibitions against acetylcholinesterase and Teucrium polium had the highest inhibition (65.8% at 1.0 mg ml(-1)). Concerning the antioxidant effect, all the extracts exerted the highest activity among all having IC50 values between 0.227 and 0.428 mg/ml.
Our data suggest that Teucrium polium among the screened plants deserves to be examined further as a herbal alternative for AD treatment.
The reaction of lipid peroxides in animal tissues with thiobarbituric acid was dependent on pH of the reaction mixture as was the case for linoleic acid hydroperoxide. The optimum pH was found to be 3.5. Taking this fact into consideration, a standard procedure for the assay of lipid peroxide level in animal tissues by their reaction with thiobarbituric acid was developed as follows. Ten percent ( tissue homogenate was mixed with sodium dodecyl sulfate, acetate buffer (pH 3.5), and aqueous solution of thiobarbituric acid. After heating at 95°C for 60 min, the red pigment produced was extracted with n-butanol-pyridine mixture and estimated by the absorbance at 532nm. As an external standard, tetramethoxy-propane was used, and lipid peroxide level was expressed in terms of nmol malondialdehyde. Using this method, the liped peroxide level in the liver of rats suffering from carbon tetrachloride intoxication was investigated. The results were in good agreement with previously reported data obtained by measuring diene content.
It is apparent that significant progress has been made in our understanding of the biosynthesis, modifications, and maturation of collagen and elastin. We now recognize and partially understand special reactions involved in hydroxylations within the cell and complex cross-linking processes occurring outside the cell. Recent experiments (191) have shown that in human diploid fibroblast cultures of limited doubling potential (191) the hydroxylation of collagen prolyl residues appears to be "age" or passage-level dependent. With increasing passage level of these cultures, both the ascorbate requirements and the extent of collagen hydroxylation decrease. "Young" cell cultures have a strong requirement for complete hydroxylation and without ascorbate there is only about 50% of the normal level. "Middle-aged" cultures show higher hydroxylation without and full hydroxylation with ascorbate, whereas "old" (or cultures close to "senescence") are incapable of full hydroxylation with or without ascorbic acid. Although the overall system may show some deterioration with increasing passage levels, it appears that with increasing passage levels other components in the cell replace the ascorbate dependence of the hydroxylase system to a greater exten. In some ways, aging WI-38 cultures begin to resemble some transformed cells in their biochemical reactions, although they continue to remain diploid and eventually lose the ability to replicate. It is not yet known whether old animals can produce collagen, which may now be underhydroxylated, perhaps contributing to certain senescent changes. Careful examination of the hydroxylation index of collagen produced in organoid cultures of tissue biopsies as a function of donor age might be informative, particularly if one looks at the quality of collagen by employing collagenase and other proteolytic digests with collagen (191). One could comare the levels of frequent and characteristic peptide triplet sequences such as Gly-Pro-Hyp to Gly-Pro-Pro, Gly-Ala-Hyp to Gly-Ala-Pro, or Gly-Pro-Hyl to Gly-Pro-Lys and others for evaluation of hydroxylation throughout the entire molecule or at selected sequences.
There is substantial evidence that ultraviolet radiation induces the formation of reactive oxygen species which are implicated as toxic intermediates in the pathogenesis of photoaging. The aim of this study was to determine whether repeated topical treatment with benzoyl peroxide, a source of free radicals, produced the same cutaneous effects as chronic ultraviolet B radiation. Three concentrations of benzoyl peroxide (0.1, 1.5, 5.0% wt/wt) and three cumulative fluences of ultraviolet B radiation (0.9, 2.2, 5.1 J per cm2) used alone and in all combinations along with appropriate controls. Female SKH1 (hr/hr) albino hairless mice were treated 5 d per wk for 12 wk. Extracellular matrix molecules and histologic parameters were assessed. Ultraviolet B radiation induced a fluence-dependent and time-dependent increase in skin-fold thickness. Fluence dependence was seen for epidermal thickness, sunburn cell numbers, dermal thickness, glycosaminoglycan content, mast cell numbers, and skin-fold thickness. Benzoyl peroxide treatment alone caused less marked increases in epidermal and dermal measures compared with ultraviolet B under the conditions used. A benzoyl peroxide concentration-dependent increase was only observed for elastin content, although the highest concentration of benzoyl peroxide increased epidermal thickness and glycosaminoglycan content. A synergistic interaction between ultraviolet B and benzoyl peroxide was not found. These results indicate that repeated administration of benzoyl peroxide produces skin changes in the hairless mouse that qualitatively resemble those produced by ultraviolet B and suggest that common mechanisms may be involved. In addition, any potential synergistic effect of ultraviolet B and benzoyl peroxide was below the level of detection used in this study.
Standardised aqueous extracts of chervil (Anthriscus cerefolium L. Hoffm.) (Apiacae) were investigated for antioxidant effect. Numerous in vitro test methods were used to determine whether the extracts, from different vegetative parts (root, herb) had H-donor, metal binding, reductive, free radical scavenging and membrane protective activity. Apiin was used as a reference material. The herb extract showed better activity in all experiments than the root extract. The present results underline that the wateric chervil extracts have antioxidant and anti-lipoperoxidant activity.
Type I and type III procollagen are reduced in photodamaged human skin. This reduction could result from increased degradation by metalloproteinases and/or from reduced procollagen synthesis. In the present study, we investigated type I procollagen production in photodamaged and sun-protected human skin. Skin samples from severely sun-damaged forearm skin and matched sun-protected hip skin from the same individuals were assessed for type I procollagen gene expression by in situ hybridization and for type I procollagen protein by immunostaining. Both mRNA and protein were reduced ( approximately 65 and 57%, respectively) in photodamaged forearm skin compared to sun-protected hip skin. We next investigated whether reduced type I procollagen production was because of inherently reduced capacity of skin fibroblasts in severely photodamaged forearm skin to synthesize procollagen, or whether contextual influences within photodamaged skin act to down-regulate type I procollagen synthesis. For these studies, fibroblasts from photodamaged skin and matched sun-protected skin were established in culture. Equivalent numbers of fibroblasts were isolated from the two skin sites. Fibroblasts from the two sites had similar growth capacities and produced virtually identical amounts of type I procollagen protein. These findings indicate that the lack of type I procollagen synthesis in sun-damaged skin is not because of irreversible damage to fibroblast collagen-synthetic capacity. It follows, therefore, that factors within the severely photodamaged skin may act in some manner to inhibit procollagen production by cells that are inherently capable of doing so. Interactions between fibroblasts and the collagenous extracellular matrix regulate type I procollagen synthesis. In sun-protected skin, collagen fibrils exist as a highly organized matrix. Fibroblasts are found within the matrix, in close apposition with collagen fibers. In photodamaged skin, collagen fibrils are shortened, thinned, and disorganized. The level of partially degraded collagen is approximately 3.6-fold greater in photodamaged skin than in sun-protected skin, and some fibroblasts are surrounded by debris. To model this situation, skin fibroblasts were cultured in vitro on intact collagen or on collagen that had been partially degraded by exposure to collagenolytic enzymes. Collagen that had been partially degraded by exposure to collagenolytic enzymes from either bacteria or human skin underwent contraction in the presence of dermal fibroblasts, whereas intact collagen did not. Fibroblasts cultured on collagen that had been exposed to either source of collagenolytic enzyme demonstrated reduced proliferative capacity (22 and 17% reduction on collagen degraded by bacterial collagenase or human skin collagenase, respectively) and synthesized less type I procollagen (36 and 88% reduction, respectively, on a per cell basis). Taken together, these findings indicate that 1) fibroblasts from photoaged and sun-protected skin are similar in their capacities for growth and type I procollagen production; and 2) the accumulation of partially degraded collagen observed in photodamaged skin may inhibit, by an as yet unidentified mechanism, type I procollagen synthesis.
This article reviews many of the complex events that occur after cutaneous ultraviolet (UV) exposure. The inflammatory changes of acute exposure of the skin include erythema (sunburn), the production of inflammatory mediators, alteration of vascular responses and an inflammatory cell infiltrate. Damage to proteins and DNA accumulates within skin cells and characteristic morphological changes occur in keratinocytes and other skin cells. When a cell becomes damaged irreparably by UV exposure, cell death follows via apoptotic mechanisms. Alterations in cutaneous and systemic immunity occur as a result of the UV-induced inflammation and damage, including changes in the production of cytokines by keratinocytes and other skin-associated cells, alteration of adhesion molecule expression and the loss of APC function within the skin. These changes lead to the generation of suppressor T cells, the induction of antigen-specific immunosuppression and a lowering of cell-mediated immunity. These events impair the immune system's capacity to reject highly antigenic skin cancers. This review gives an overview of the acute inflammatory and immunological events associated with cutaneous UV exposure, which are important to consider before dealing with the complex interactions that occur with chronic UV exposure, leading to photocarcinogenesis.
Modulation of pathological angiogenesis by curcumin (diferuloylmethane), the active principle of turmeric, seems to be an important possibility meriting mechanistic investigations. In this report, we have studied the effect of curcumin on the growth of Ehrlich ascites tumor cells and endothelial cells in vitro. Further, regulation of tumor angiogenesis by modulation of angiogenic ligands and their receptor gene expression in tumor and endothelial cells, respectively, by curcumin was investigated. Curcumin, when injected intraperitoneally (i.p) into mice, effectively decreased the formation of ascites fluid by 66% in EAT bearing mice in vivo. Reduction in the number of EAT cells and human umbelical vein endothelial cells (HUVECs) in vitro by curcumin, without being cytotoxic to these cells, is attributed to induction of apoptosis by curcumin, as is evident by an increase in cells with fractional DNA content seen in our results on FACS analysis. However, curcumin had no effect on the growth of NIH3T3 cells. Curcumin proved to be a potent angioinhibitory compound, as demonstrated by inhibition of angiogenesis in two in vivo angiogenesis assay systems, viz. peritoneal angiogenesis and chorioallantoic membrane assay. The angioinhibitory effect of curcumin in vivo was corroborated by the results on down-regulation of the expression of proangiogenic genes, in EAT, NIH3T3, and endothelial cells by curcumin. Our results on Northern blot analysis clearly indicated a time-dependent (0-24h) inhibition by curcumin of VEGF, angiopoietin 1 and 2 gene expression in EAT cells, VEGF and angiopoietin 1 gene expression in NIH3T3 cells, and KDR gene expression in HUVECs. Further, decreased VEGF levels in conditioned media from cells treated with various doses of curcumin (1 microM-1mM) for various time periods (0-24h) confirm its angioinhibitory action at the level of gene expression. Because of its non-toxic nature, curcumin could be further developed to treat chronic diseases that are associated with extensive neovascularization.
A water-soluble (at pH 8) aromatic disulfide [5,5′-dithiobis(2-nitrobenzoic acid)] has been synthesized and shown to be useful for determination of sulfhydryl groups.Several applications have been made to show its usefulness for biological materials.A study of the reaction of this disulfide with blood has produced some evidence for the splitting of disulfide bonds by reduced heme.
A 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-generating system was used to evaluate the antioxidant properties of Korean medicinal plants that have been used widely as folk medicines for several disorders, as well as compounds isolated from them. Among the Rosaceae, Rosa rugosa and Rosa davurica showed strong DPPH radical-scavenging activity. The most effective medicinal plant from families other than Rosaceae was Cedrela sinensis, followed in order by Nelumbo nucifera, Eucommia ulmoides, Zanthoxylum piperitum, Cudrania tricuspidata and Houttuynia cordata. These results serve as a good index of the free radical-scavenging activities of Korean medicinal plants. Furthermore, the polyphenols isolated from these plants, procyanidin B-3, (+)-catechin, gallic acid, methyl gallate, quercetin, quercetin-3-O-beta-D-glucoside, quercetin-3-O-beta-galactoside, quercetin-3-O-rutinose and kaempferol, exerted strong DPPH radical-scavenging activity. These results suggest that the Korean medicinal plants and the polyphenols isolated from them that exhibited effective radical-scavenging activity may be promising agents for scavenging free radicals and treating diseases associated with excess free radicals.
The use of psoralen-UVA (PUVA) in patients of skin phototype I to II is limited by side effects of acute phototoxicity and possible long-term carcinogenesis.
We sought to assess oral Polypodium leucotomos (PL) extract in decreasing PUVA-induced phototoxicity of human skin on a clinical and histologic level.
A total of 10 healthy patients with skin phototypes II to III were exposed to PUVA alone (using 0.6 mg/kg oral 8-methoxypsoralen) and to PUVA with 7.5 mg/kg of oral PL.
Clinically, phototoxicity was always lower in PL-treated skin after 48 to 72 hours (P<.005), and pigmentation was also reduced 4 months later. Histologically, PL-treated skin showed a significant numeric reduction of sunburn cells (P=.05), preservation of Langerhans cells (P< or =.01), decrease of tryptase-positive mast cell infiltration (P<.05), and decrease of vasodilation (P< or =.01). No differences were found in Ki-67+ proliferating cells.
PL is an effective chemophotoprotector against PUVA-induced skin phototoxicity and leads to substantial benefits of skin protection against damaging effects of PUVA as evidenced by histology.
Chronic exposure of solar ultraviolet (UV) light to human skin results in photoaging. UV-induced oxidative damage and induction of matrix metalloproteinases (MMP) have been implicated in this process. Because polyphenols from green tea (GTP) prevent other cutaneous adverse effects of UV radiation we hypothesized that UV irradiation-induced oxidative damage and induction of MMP might be prevented in vivo in mouse skin by oral administration of GTP. GTP was administered in drinking water (0.2%, wt/vol) to SKH-1 hairless mice, which were then exposed to multiple doses of UVB (90 mJ per cm2, for 2 mo on alternate days) following in vivo photoaging animal protocol. Treatment of GTP resulted in inhibition of UVB-induced protein oxidation in vivo in mouse skin, a hallmark of photoaging, when analyzed biochemically, by immunoblotting, and immunohistochemistry. GTP treatment also inhibited UVB-induced protein oxidation in vitro in human skin fibroblast HS68 cells, which supports in vivo observations. Moreover, oral administration of GTP also resulted in inhibition of UVB-induced expression of matrix degrading MMP, such as MMP-2 (67%), MMP-3 (63%), MMP-7 (62%), and MMP-9 (60%) in hairless mouse skin. These data suggest that GTP as a dietary supplement could be useful to attenuate solar UVB light-induced premature skin aging.
A rapid and specific reversed-phase high performance liquid chromatography (RP-HPLC) method with diode array detection (DAD) at room temperature was used and validated for the simultaneous determination of five flavonoids (catechin, CA; rutin, RU; quercetin, QU; kaempferol, KA; isorhamnetin, IS) in the extract of sea buckthorn (Hippophae rhamnoides L.) leaves. The sample pretreatment process involved ultrasonic extraction with 85% ethanol under the frequency of 80 kHz, at a temperature of 45 degrees C for 30 min and with the ratio of liquor to material of 15 mL g-1, followed by separation on HIQ SIL C18V column with methanol-acetonitrile-water (40:15:45, v/v/v) containing 1.0% acetic acid as a mobile phase. The extract was detected by DAD at the wavelength of 279 nm for CA, 257 nm for RU, 368 nm for QU, KA and IS. Calibration curves were found to be linear with the ranges of 0.011-0.520 mg ml-1 (CA), 0.007-0.500 mg ml-1 (RU), 0.019-0.280 mg ml-1 (QU), 0.010-0.440 mg ml-1 (KA) and 0.008-0.400 mg ml-1 (IS). The correlation coefficients of linear regression analysis and detection limits were between 0.9963-0.9999 and 0.00079-0.00290 mg ml-1. The contents of CA, RU, QU, KA and IS in sea buckthorn leaves were successfully determined with 3.8, 5.2, 7.3, 10.9 and 11.9 min with satisfactory reproducibility and recovery. Recoveries of the five flavonoids were between 97.27 and 99.98%. The method was applied to the determination of flavonoids in sea buckthorn leaves and was found to be simple, rapid and efficient.
Unlabelled:
Aging is a complex, multifactorial process resulting in several functional and esthetic changes in the skin. These changes result from intrinsic as well as extrinsic processes, such as ultraviolet radiation. Recent advances in skin biology have increased our understanding of skin homeostasis and the aging process, as well as the mechanisms by which ultraviolet radiation contributes to photoaging and cutaneous disease. These advances in skin biology have led to the development of a diversity of treatments aimed at preventing aging and rejuvenating the skin. The focus of this review is the mechanism of photoaging and the pathophysiology underlying the treatments specifically designed for its prevention and treatment.
Learning objectives:
At the conclusion of this learning activity, participants should be familiar with the mechanism of photoaging, the treatments for photoaging, and the data that supports the use of these treatments.
We have previously shown that targeted overexpression of the endogenous angiogenesis inhibitor thrombospondin-1 (TSP-1) in the epidermis prevented chronic ultraviolet B (UVB)-induced angiogenesis and cutaneous photodamage in mice, suggesting that angiogenesis plays a critical role in the mediation of UVB effects on the skin. Nevertheless, the molecular regulation of angiogenesis factors and inhibitors by acute UVB irradiation still remains to be elucidated. We performed quantitative analyses of cutaneous vascularity and of vascular endothelial growth factor (VEGF) and TSP-1 expression after acute UVB irradiation of mouse skin. Skin vascularity in the upper dermis was greatly increased until day 8 after a single dose of UVB irradiation (200 mJ per cm2) and associated with upregulation of VEGF mRNA expression, with downregulation of TSP-1 mRNA, and with protein expression in the hyperplastic epidermis. After 13 days, skin vascularity was normalized with downregulation of VEGF mRNA expression and upregulation of TSP-1 mRNA expression to the levels observed in non-UVB-irradiated skin. In contrast, the angiogenic UVB response was prolonged in TSP-1-deficient mice. We found a pronounced induction of the TSP-1 receptor CD36 in CD31-positive vessels on day 8 after UVB irradiation, associated with vascular endothelial cell apoptosis. These results demonstrate that acute UVB irradiation leads to a shift toward a proangiogenic environment and they suggest that the balance between VEGF and TSP-1 plays a critical role in the control of angiogenesis and vascular regression induced by acute UVB irradiation.
Ultraviolet light induced injury: immunological and inflammatory effects
- G J Clydesdale
- G W Dandie
- H K Muller
Clydesdale GJ, Dandie GW, Muller HK. Ultraviolet light induced injury:
immunological and inflammatory effects. Immunol Cell Biol 2001;79:547-68.