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The species Andrographis paniculata L. Ness, family Acanthaceae grows in many parts in the island of Java in Indonesia. In this research, new potentials of photoprotective agents from A. paniculata plant extracts, along with their characteristics, were investigated. The phytochemical test, infrared analysis, ultraviolet characterization, fluorescence identification, flavonoid content by thin layer chromatography, high performance liquid chromatography-mass spectrometry (LCMS/MS) and photoprotective analysis were performed in the extracts. The new potentials of A. paniculata plant extracts were studied at various concentrations of extracts and shown by the value of the sun protection factor (SPF). Based on phytochemical test, A. paniculata plant extracts contained flavonoids, alkaloids, tannins, triterpenoids and polyphenols. A. paniculata plant extracts have 2 maximum wavelengths at 230 nm and 362 nm. The excitation peak at 300 nm (552.11 a.u) and the emission peak at 605 nm (516.02 a.u). The flavonoid content of the extracts was 0.022 µg/mL quercetin with Rf value of 0.61. The chromatogram of the LCMS/MS is similar to quercetin-3-glycoside standard at a retention time of 2.77. The photoprotective activity of A. paniculata plant extracts had ≥ 15 SPF. Its shows the possibility to use this extract as photoprotective agent in pharmaceutical preparations.

The study aimed to examine whether usnic acid—a lichen compound with UV-absorbing properties—can be considered as a prospective photoprotective agent in cosmetic products. Moreover, a comparison of two usnic acid enantiomers was performed to preselect the more effective compound. To meet this aim, an in vitro model was created, comprising the determination of skin-penetrating properties via skin-PAMPA assay, safety assessment to normal human skin cells (keratinocytes, melanocytes, fibroblasts), and examination of photostability and photoprotective properties. Both enantiomers revealed comparable good skin-penetrating properties. Left-handed usnic acid was slightly more toxic to keratinocytes (IC50 80.82 and 40.12 µg/mL, after 48 and 72 h, respectively) than its right-handed counterpart. The latter enantiomer, in a cosmetic formulation, was characterized by good photoprotective properties and photostability, comparable to the UV filter octocrylene. Perhaps most interestingly, (+)-usnic acid combined with octocrylene in one formulation revealed enhanced photoprotection and photostability. Thus, the strategy can be considered for the potential use of (+)-usnic acid as a UV filter in cosmetic products. Moreover, the proposed model may be useful for the evaluation of candidates for UV filters.

Ultraviolet (UV)-B radiation is a major environmental risk factor that is responsible for the development and progression of many skin cancers. Apigenin, a type of bioflavonoid, has been reported to inhibit UVB-induced skin cancer. However, how apigenin functions in keratinocytes with UV damage remains unclear. In this study, by lactate dehydrogenase (LDH) release assay, we found that apigenin treatment increased cell death in the primary human epidermal keratinocytes (HEKs) and the cutaneous squamous cell carcinoma cell line COLO-16. Apigenin treatment reduced microtubule-associated protein 1 light chain 3 (LC3)-II turnover, acridine orange staining and GFP-LC3 puncta in both cell types, suggesting autophagy inhibition. However, apigenin treatment restored the inhibition of autophagy in UVB-challenged HEKs. Moreover, apigenin treatment restored the UVB-induced downregulation of ataxia-telangiectasia mutated (ATM), ataxia-telangiectasia, Rad3-related (ATR) and the unfolded protein response (UPR) regulatory proteins, BiP, IRE1α and PERK in HEKs. Apigenin treatment also inhibited UVB-induced apoptosis and cell death in HEKs. In addition, autophagy inhibition by autophagy-related gene (ATG) 5 RNA interference interrupted apigenin-induced restoration of ATR, ATM and BiP, which were downregulated in HEKs exposed to UVB radiation. Our findings indicate that apigenin exhibits a novel protective effect in keratinocytes with UVB damage, suggesting potential application as a photoprotective agent.

Prolonged exposure to Ultra Violet Radiation (UVR) adversely alters the functions of many skin cell types causing skin cancer and photoaging, which had led to increase in demand for more safe and natural sunscreens against UVR. The present study focuses on production, structural characterization and evaluation of photoprotective nature of melanin pigment derived from lime dwelling Pseudomonas sp. Melanin was characterized by solubility, UV–Vis, FT-IR, 13C-CPMAS, ESI-MS spectroscopy, including particle size, melting point and elemental analyses. In vitro cytotoxicity and photo-protective effect of Pseudomonas derived melanin (Mel-P) against UV-B (Broad Band-BB) radiations were assessed on mouse fibroblasts NIH 3 T3 cell lines. Reactive Oxygen Species (ROS) generated in NIH 3 T3 cells upon UV-B (BB) exposure was determined and quantified by Fluorescent microscopic and Flow cytometric analyses. A natural melanin obtained from Pseudomonas sp. contains 5,6- dihydroxy indole 2-carboxyic acid (DHICA) as its basic constituent and possess typical properties of eumelanin as revealed by the characterization studies. Mel-P has shown cell viability of 61.33 ± 6.58% at the concentration of 500 μg/mL proving its non-cytotoxic effect. Owing to its anti-oxidant property, melanin efficiently protected the mouse fibroblast cells from UV-B (BB) irradiation in a dose dependant manner demonstrating its potential as an active photoprotective agent.

Safranal, a monoterpene aldehyde, is present as one of the main volatile constituents of Crocus sativus Linn. (saffron flowers). This volatile constituent not only contributes to the aroma of saffron but has been reported to possess antidiabetic, antiulcer, antiasthamatic, anticonvulsant, antidepressant, cardioprotective, anticancer and UV protective properties. Most of these therapeutic actions are contributed by its potential to quench reactive oxygen species (ROS). Antioxidant properties of phytoconstituents are now being explored for developing photoprotective skin formulations. These bioactives have the potential to protect the epidermal and dermal layers of the skin which mainly comprises of elastin and collagen. When UV rays penetrate the dermal layers, there is an increased production of elastase, collagenase and hyaluronidase leading to degradation of collagen, elastin and hyaluronic acid respectively. These dermal components are responsible to provide strength, elasticity and moisture to the skin. Due to frequent exposure to sunlight, these conditions tend to augment leading to wrinkle formation and sagging of skin. Although antioxidant properties of safranal have been established on various cell lines but till date no studies have been reported regarding the dermal enzyme inhibition activities. In the current research work, a comprehensive in vitro evaluation of antioxidant, anti-elastase, anti-collagenase, anti-hyaluronidase activities of safranal along with determination of sun protection factor (SPF) was carried out. The in vitro antioxidant activity was carried out by diphenylpicrylhydrazyl (DPPH) method and its IC50 value was found to be 22.7 μg/ml. The enzyme inhibition IC50 values of safranal for anti elastase activity were found to be 43.6 μg/ml, 70 μg/ml for antihyaluronidase activity and 9.4 μg/ml for anticollagenase activity. Photoprotective activity of safranal was determined by UV absorbance method and SPF calculated by Mansur equation which was found to be 6.6. The significant inhibitory activity of safranal on matrix metalloproteinases (MMPs) responsible for aging and a higher SPF established that this bioorganic molecule is a strong photoprotective agent. Its established free radical scavenging capability along with above characteristics make it a valuable component to be incorporated into herbal antiaging formulations.

A simple 3-step synthesis of a novel pyrazine-containing heteroaromatic building block for use as a scaffold for producing multi-chromophoric sensitizers for use in dye sensitized solar cells has been developed. This moiety features two esterified carboxylic acid groups whose hydrolysis provides moieties for anchoring to nanoparticulate metal oxides and two bromine atoms that facilitate attachment of chromophores via palladium mediated cross-coupling methods. The utility of the building block for the synthesis of complex dye motifs is demonstrated by the preparation of a novel panchromatic dye featuring a BODIPY chromophore and a strongly electron donating porphyrin chromophore using both Suzuki and copper-free Sonogashira cross-coupling methods. The building block could be used either to attach two different or identical dye moieties to the metal oxide, or to attach an electron injection dye plus an auxiliary absorber, photoprotective agent, secondary redox moiety, etc.

Approaches to the polyene natural product xanthomonadin, an octaenyl electron-deficient bacterial photoprotective agent, and its debromo analogue, were developed. These involved the iterative cross-coupling of multiple C2-fragments, using a vinylboronate ester as a formal vinyl dianion equivalent. Vinyl iodide starting materials undergo Heck-Mizoroki cross-coupling at ambient temperatures, allowing further iododeboronation to derive the next vinyl iodide. This works in a highly effective manner to access systems of up to pentaene chain length. However, final assembly of polyenylboronates with such polyenyl iodides through their Suzuki-Miyaura cross-coupling was less successful, even at lower temperatures, reflecting the extreme sensitivity of such octaenylxanthomonadin analogues. Despite this, the mild cross-coupling conditions could be effectively applied to the assembly of a range of useful polyenyl building blocks, as well as a truncated pentaenyl-debromoxanthomonadin analogue.

Sunscreens today contain several synthetic UV (Ultraviolet) filter molecules to protect the skin epidermis from UV radiation damage. However, these molecules may create several negative effects on human skin. Due to this condition, there is an increase in the development of natural products to replace uses of these synthetic chemicals. Brown macroalgae Sargassum has been recently studied for its photoprotective activities. The purpose of this study is to investigate photoprotective activity of one of most abundant Sargassum species in Lombok coast, Sargassum cristaefolium. Spectrophotometry analysis with UV-VIS revealed the UV spectra absorbing capability of Sargassum cristaefolium (SC) in the UVA spectrum range (314&ndash, 400 nm). Furthermore, spectrometry analyses with LC-MS revealed the existence of UV absorbing compound MAA-palythene. In correlation, SC ethanol extracts also demonstrate that it could protect DNA from UVA irradiation as analyzed in vitro in HeLa cell model. The effects of SC on UVA exposed-dorsal mice skin have also shown interesting results, as mice pretreated with SC before UVA exposure showed protective activity on the epidermal integrity similar as positive control. Whereas, UV exposed mice without SC or commercial products resulted in increased epidermal thickness, which is the common parameter of skin photoaging. In addition, pretreated mice with SC also show protective effects in the formation of collagen connective tissues. Overall, current results show promising photoprotective activity of SC against UV radiation. More advanced investigations of SC as a potential photoprotective agent would be reasonable for development of macroalgae-based natural skin protection products.

Many fungi are thought to have developed morphological and physiological adaptations to cope with exposure to UV-B radiation, but in most species, such responses and their protective effects have not been explored. Here, we study the adaptive response to UV-B radiation in the widespread, saprotrophic fungus Serpula himantioides, frequently found colonizing coniferous wood in nature. We report the morphological and chemical responses of S. himantioides to controlled intensities of UV-B radiation, under in vitro culture conditions. Ultraviolet radiation induced a decrease in the growth rate of S. himantioides but did not cause gross morphological changes. Instead, we observed accumulation of pigments near the cell wall with increasing intensities of UV-B radiation. Nuclear magnetic resonance (NMR) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses revealed that xerocomic acid was the main pigment present, both before and after UV-B exposure, increasing from 7 mg/liter to 15 mg/liter after exposure. We show that xerocomic acid is a photoprotective metabolite with strong antioxidant abilities, as evidenced by DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt], and oxygen radical absorbance capacity (ORAC) assays. Finally, we assessed the capacity of xerocomic acid as a photoprotective agent on HEK293 cells and observed better photoprotective properties than those of β-carotene. Xerocomic acid is therefore a promising natural product for development as a UV-protective ingredient in cosmetic and pharmaceutical products. IMPORTANCE Our study shows the morphological and chemical responses of S. himantioides to controlled doses of UV-B radiation under in vitro culture conditions. We found that increased biosynthesis of xerocomic acid was the main strategy adopted by S. himantioides against UV-B radiation. Xerocomic acid showed strong antioxidant and photoprotective abilities, which has not previously been reported. Our results indicate that upon UV-B exposure, S. himantioides decreases its hyphal growth rate and uses this energy instead to increase the biosynthesis of xerocomic acid, which is allocated near the cell wall. This metabolic switch likely allows xerocomic acid to efficiently defend S. himantioides from UV radiation through its antioxidant and photoprotective properties. The findings further suggest that xerocomic acid is a promising candidate for development as a cosmetic ingredient to protect against UV radiation and should therefore be investigated in depth in the near future both in vitro and in vivo.

Ultraviolet B (UVB) induces inflammation and causes skin aging. The signs of skin aging, such as wrinkles, discolored spots, loss of skin moisture, and disruption of the skin barrier, are mostly caused by inflammatory signaling among various skin layers. The cells on the outermost surface of the skin are keratinocytes; these cells protect the skin against environmental stress and play an important role in immunomodulation by secreting cytokines in response to environmental stress. In the present study, we found that UVB activates STAT1 to mediate inflammatory signaling, yet STAT1 (S272) and STAT (Y702) shows different responses against UVB exposure. Anhua drak tea is a post-fermented dark tea produced in Anhua and Xinhua country in Hunan province of China. Treatment with 2S,3R-6-methoxycarbonylgallocatechin (MCGE), an epigallocatechin gallate derivative isolated from black tea (Anhua dark tea), effectively suppresses STAT1 activation and inflammatory cytokines, and activates Nrf2 pathway to protect cells from reactive oxygen species production in UVB exposed keratinocyte cells (HaCaT). Interestingly, the effects of MCGE were independent on MAPK signaling pathway. Moreover, MCGE regulates inflammatory cytokines in monocyte-keratinocyte (THP-1, HaCaT) co-culture and macrophage differentiation models. These results suggest that MCGE potentially can be used as a photoprotective agent against UVB-induced inflammatory responses.

Effective protection from the harmful effects of UV radiation may be achieved by using sunscreens containing organic or inorganic UV filters. The number of currently available UV filters is limited and some of the allowed molecules possess limitations such as systemic absorption, endocrine disruption properties, contact and photocontact allergy induction, and low photostability. In the search for new organic UV filters we designed and synthesized a series consisting of 5-benzylidene and 5-(3-phenylprop-2-en-1-ylidene)imidazolidine-2,4-dione (hydantoin) derivatives. The photoprotective activity of the tested compounds was confirmed in methanol solutions and macrogol formulations. The most promising compounds possessed similar UV protection parameter values as selected commercially available UV filters. The compound diethyl 2,2&prime, ((Z)-4-((E)-3-(4-methoxyphenyl)allylidene)-2,5-dioxoimidazolidine-1,3-diyl)diacetate (4g) was characterized as an especially efficient UVA photoprotective agent with a UVA PF of 6.83 &plusmn, 0.05 and favorable photostability. Diethyl 2,2&prime, ((Z)-4-(4-methoxybenzylidene)-2,5-dioxo- imidazolidine-1,3-diyl)diacetate (3b) was the most promising UVB-filter, with a SPFin vitro of 3.07 &plusmn, 0.04 and very good solubility and photostability. The main photodegradation products were geometric isomers of the parent compounds. These compounds were also shown to be non-cytotoxic at concentrations up to 50 &micro, M when tested on three types of human skin cells and possess no estrogenic activity, according to the results of a MCF-7 breast cancer model.

Introduction Different strategies are applicable to protect skin against the harmful effects which may appear due to an overexposure to UV radiation including the use of sunscreens. Natural polyphenols have shown an interesting activity as photoprotectors. This study aimed to assess the potentiality of a Tunisian halophyte plant, Carpobrotus edulis L. (CE) as a candidate for topical photoprotection. Methods A phytochemical characterization of CE aqueous leaf extract was processed by quantification of total polyphenols and flavonoids contents as well as by FT-IR, UV and LC-MS analysis. The plant extract was, then, incorporated into an oil-in-water (O/W) cream and assessed for its in vitro antioxidant properties and sun protection factor (SPF). Results Phytochemical characterization highlighted the richness of the aqueous extract in polyphenols. LC-MS analysis permitted the identification of 20 phenolic compounds. Catechin, procyanidin B2, dihydromyricetin and syringetin-3-O-rutinoside were the most predominant components (19.39%, 16.04%, 12.85% and 14.28% respectively). UV spectrophotometric analyses showed that CE extract absorbed in the UV region (190–400 nm). C.E crude extract exhibited, at the concentration of 1000 µg/ml, a high photoprotective effect with a SPF value of 6.996 ± 0.174 corresponding to a percent of UV blockage ranging from 80 to 90%. Besides, when it was incorporated into an O/W emulsion at a concentration of 10% (m/m), it presented a good antioxidant activity (DPPH inhibition (%) ≈ 70%) and an in vitro SPF value of 1.626 ± 0.466 corresponding to a percent of UV blockage ≈50%. Conclusion These results suggest that Carpobrotus edulis L. could be a good topical photoprotective agent.

Omega 3 polyunsaturated fatty acids (omega 3 PUFA) are attracting a growing interest as potential adjuvants for cancer prevention and treatment. There is evidence about photoprotection in normal cells, but few previous studies have evaluated it in tumoral cells. Therefore, this study investigated the effect of α-linolenic acid (ALA) in normal murine melanocytic cells (Melan-a) and in tumoral murine melanocytic cells (B16F10) exposed to UVB radiation. Our results showed that ALA exhibited an antiproliferative effect in B16F10 cells, and had minimal effect in Melan-a cells, as demonstrated by MTT assay. On the other hand, the combination of ALA (7.5μM) and UVB (0.01J/cm2) showed a protective effect for both cell lines, Melan-a and B16F10. ALA and UVB combined or UVB alone induced an accumulation of cell lines at the S/G2/M phase. In addition, the combination of ALA and UVB, and UVB alone, both induced cell death in 24h; and in 48h, ALA attenuated this effect in both cells. Further to these findings, it was demonstrated that ALA did not alter ROS levels in both cells exposed to UVB radiation. The effect of an omega 6 PUFA, linoleic acid, under the same conditions of ALA were tested. It was not protective in either cell line. Therefore, our results can be very important since it was shown another role to an omega 3 PUFA as a photoprotective agent in a melanoma cell.

Ferulic acid (4-hydroxy-3-methoxycinnamic acid) is a phytochemical constituent from the polyphenols group commonly found in whole grains, spinach, parsley, grapes and rhubarb. It has been widely applied in skin care formulations as photoprotective agent and delayer of cutaneous photoaging processes. This work aims to establish a protocol to the development of cosmetic formulations using thermoanalytical techniques (TG/DTG and DSC) and Pearson’s correlation by FTIR data, in order to evaluate the compatibility between ferulic acid and excipients used in skin care formulations. The results obtained from the thermoanalytical techniques indicated compatibility between ferulic acid and the following excipients: passion fruit seed oil, Carbopol® Ultrez 30, EDTA, Crodabase CR2®, Crodamol™ GTCC and Dow Corning® RM 2051. Nevertheless, the analysis also demonstrated the possibility of some interaction between ferulic acid and the following excipients: glyceryl stearate, Rapithix® A-60 and Optiphen®. To validate these results, it was demonstrated by Pearson’s correlation that passion fruit seed oil, Carbopol® Ultrez 30, EDTA, Crodabase CR2®, Crodamol™ GTCC, Dow Corning® RM 2051, glyceryl stearate and Rapithix® A-60 do not have any incompatibility that may compromise ferulic acid properties. Finally, it was also proved a meaningful incompatibility between ferulic acid and Optiphen® using Pearson’s correlation. Thus, it is not recommended to use Optiphen® in the development of cosmetic formulations to carry ferulic acid.

Cinnamic acid plays a vital role in the synthesis of other important compounds and as a precursor for the synthesis of commercial cinnamon esters used in perfumery, cosmetics, and pharmaceutical industries. The aim of this research is to synthesize cinnamic acid using sonochemical methods. Cinnamic acid was synthesized using Perkin reaction by reacting 0.05 mole of benzaldehyde with 0.073 mole of acetic acid anhydride and 0.03 mole of sodium acetate as a catalyst in the Erlenmeyer flask and then the mixture was put in a sonicator for 60 minutes at 70 oC. The synthesized compound was tested organoleptic properties, and the melting point was measured. The chemical structure was elucidated using FT-IR, H-NMR, and 13C-NMR. The photoprotective activity was examined from its antioxidant and SPF values. The synthesized compound was found in the form of a shiny white fine crystal which had distinctive odor with a yield of 4.98% and the melting point was found at 133 oC. In the structure elucidation using FT-IR (the aromatic ring absorption at the wave number 1580 cm-1 -1600 cm-1. The wave number 1625 cm-1is an aromatic conjugated alkene group, while wave number 1689.4 cm-1 is a carbonyl group. The wave number 2500 cm-1 – 3250 cm-1 is an OH carboxylic acid group) , H-NMR (7.410 (m, 5H, Ar-H); 7.425(t, 1H); 7.572 (d, 1H); 8.057 (d, 1H,C=CH) and 13C-NMR (129.309 ppm; 130.998 ppm; 134.58 ppm; 170.017 ppm) showed that when compared with the standard compound as the reference, the synthesized compound was confirmed to be cinnamic acid. The antioxidant activity test showed that at the concentration of 20 ppm the synthesized compound was able to reduce free radicals by 46.69%. This finding showed that the synthesized compound had antioxidant activity.

Ferulic acid has low toxicity and possesses many physiological functions (anti-inflammatory, antioxidant, antimicrobial activity, anticancer, and antidiabetic effect). It has been widely used in the pharmaceutical, food, and cosmetics industry. Ferulic acid is a free radical scavenger, but also an inhibitor of enzymes that catalyze free radical generation and an enhancer of scavenger enzyme activity. Ferulic acid has a protective role for the main skin structures: keratinocytes, fibroblasts, collagen, elastin. It inhibits melanogenesis, enhances angiogenesis, and accelerates wound healing. It is widely applied in skin care formulations as a photoprotective agent, delayer of skin photoaging processes, and brightening component. Nonetheless, its use is limited by its tendency to be rapidly oxidized.

Vegetable oils are well-known for their beneficial health effects, mainly due to their antioxidant activity, which is maintained or enhanced when they are encapsulated at nanoscale. This study aims to design new nanostructured lipid carriers (NLCs) containing various vegetable oils and their combinations in order to obtain efficient formulations with UV protection performance and antioxidant activity. Pomegranate seed oil, wheat germ oil, blackcurrant seed oil, sesame seed oil, carrot root oil, raspberry seed oil and rice bran oil were used for obtaining NLCs, as carriers for a photoprotective agent that absorbs the UVA radiation: diethylamino hydroxybenzoyl hexyl benzoate. The NLCs were characterized by mean particle size, physical stability over time, and entrapment efficiency of the UVA filter. The UV protection performance was assessed using both in vitro sun protection factor (SPF) and the UVA protection factor (UVAPF). The antioxidant activity was determined by chemiluminescence analysis. All vegetable oils used led to the development of appropriate NLCs, having mean particle sizes ranging between 100 nm and 145 nm and good physical stability with zeta potential values less negative than −35 mV. The UV protection factors were evaluated on the individual vegetable oils and on cream formulations based on NLCs. Out of the seven cream formulations, the best UV protection was assured by the pomegranate seed oil based cream resulting in a SPF of 4.1 and an UVAPF of 7.8. Knowing that a synergistic interaction can occur among the active compounds of different oils, new NLCs were developed by using a mixture of pomegranate seed oil and one of the other oils. The NLCs based on pomegranate seed oil combined with wheat germ oil have shown the best entrapment efficiency (70%) and photoprotection (SPF of 5.1 and a UVAPF of 9.5). All vegetable oils showed a good antioxidant activity, which was improved by their incorporation into NLCs. The results have shown that vegetable oils and especially their combinations can be used as renewable raw materials in designing effective and eco-friendly photoprotective nanostructured formulations.

As the understanding of the immune system pathways, cytokine balances, and cellular interactions continues to expand, so must the potential applications of therapies that can impact the process of diseases instead of just controlling their symptoms. In the case of Polypodium leucotomos extract, which is derived from a tropical fern of the Polypodiaceae family, the future potential of applications in dermatology and beyond will be better understood as its incorporation into daily routines gives rise to the development of new regimens. Clinicians may position this agent as an option for daily maintenance, accept its use in combinations, or use it as a template for further development of oral supplementation that may evolve into a true immunomodulator. The antioxidant activity of P. leucotomos extract is primarily driven by caffeic acid and ferulic acid, resulting in the control of cutaneous responses to ultraviolet-induced erythema, in the interception of inflammatory mechanisms, and the promotion of other cytotoxic responses. Histologically, the impact of P. leucotomos extract induces an effect on the overall reduction of angiogenesis, photocarcinogenesis, and solar elastosis, while on the cellular level there are improvements in cell membrane integrity and elastin expression. Future applications for P. leucotomos extract could include the potential for photoprotective effects, and subsequent research efforts should focus on determining the optimal dosage regimen, duration of action, and utility of combinations with sunscreens, among other outcomes. Recently published data have also demonstrated how the antioxidant effects of oral P. leucotomos extract can delay tumor development in mice models, suggesting there might be a protective role that could be described with further clinical research. In addition, it is important to recognize the distinction between photoprotection and chemoprevention, in that there has yet to be any in vivo or controlled clinical trial data in human subjects that show a role for P. leucotomos extract in the prevention of carcinogenesis.

Ultraviolet-B radiation (285–320 nm) elicits a number of cellular signaling elements. We investigated the preventive effect of linalool, a natural monoterpene, against UVB-induced oxidative imbalance, activation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling in HDFa cells. We observed that linalool treatment (30 μM) prevented acute UVB-irradiation (20 mJ/cm 2) mediated loss of activities of antioxidant enzymes in HDFa cells. The comet assay results illustrate that linalool significantly prevents UVB-mediated 8-deoxy guanosine formation (oxidative DNA damage) rather than UVB-induced cyclobutane pyrimidine (CPD) formation. This might be due to its ability to prevent UVB-induced ROS formation and to restore the oxidative imbalance of cells. This has been reflected in UVB-induced overexpression of MAPK and NF-κB signaling. We observed that linalool inhibited UVB-induced phosphorylation of ERK1, JNK and p38 proteins of MAPK family. Linalool inhibited UVB-induced activation of NF-κB/p65 by activating IκBa. We further observed that UVB-induced expression of TNF-α, IL6, IL-10, MMP-2 and MMP-9 was modulated by linalool treatment in HDFa cells. Thus, linalool protects the human skin cells from the oxidative damages of UVB radiation and modulates MAPK and NF-κB signaling in HDFa cells. The present findings substantiate that linalool may act as a photoprotective agent against UVB-induced skin damages.

Photoprotective potential and biological consequences (mutagenic potential) of octyl-dimethyl-PABA (ODP), titanium dioxide (TiO2), and montmorillonite (MMT) upon ultraviolet B (UVB) irradiation, alone and in different associations [physical mixtures (PMs)], were evaluated using a Saccharomyces cerevisiae ogg1 mutant (deficient) strain. In addition, we developed and characterized a delaminated TiO2-pillared MMT, called the TiO2–MMT nanocomposite (NC), which was also investigated in terms of its photoprotective and mutagenic potential. Overall, our results revealed an interesting TiO2–MMT NC endowed with antimutagenic activity that can be associated to organic sunscreen molecule (ODP) and still maintain its positive effect, whereas its respective PM is unable to grant antimutagenic protection against UVB. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:2539–2545, 2014

Background EGb-761 is an antioxidant and anticarcinogen; however, its role as a photoprotector remains unknown. Objective To determine whether EGb-761 photoprotects human dermal fibroblasts and BALB/c mice skin against ultraviolet B (UVB) light irradiation. Methods To simulate chronic photodamage, shaved BALB/c mice were exposed to UVB irradiation (90 mJ/cm2) thrice weekly for 3 months. EGb-761 (2 mg/cm2) was topically applied 1 h before irradiation to evaluate its effect. The mechanisms by which EGb-761 protects the skin from photodamage were evaluated by immunohistochemical analysis, enzyme-linked immunosorbent assay (ELISA), and Western blotting. Results In BALB/c mice, the signs of photoaging or photodamage, such as coarse wrinkle formation, epidermal hyperplasia, and elastic fiber degeneration, markedly reduced with the topical application of EGb-761. Western blot and ELISA revealed that the activation of MMP-1 in cultured fibroblasts markedly diminished after pretreatment with EGb-761. In addition, EGb-761 inhibited UVB-induced overexpression by the fibroblasts of the proinflammatory cytokines, such as interleukin (IL)-1α, IL-1β, IL-6, and tumor necrosis factor-α. The phosphorylation of the mitogen-activated protein kinase (MAPK) signal transduction pathway components, including extracellular signal-regulated kinase, C-Jun N-terminal kinase, and p38, which are induced by UV irradiation, was significantly inhibited in vivo and in vitro. EGb-761 also diminished the generation of UVB-induced reactive oxygen species (ROS). Conclusions EGb-761 photoprotects mice and cultured fibroblasts, inhibits the UVB-induced phosphorylation of MAPK pathway components, and reduces the expression of the proinflammatory cytokines by suppressing ROS generation. Thus, topically applied EGb-761 may be a promising photoprotective agent.

Trehalose, a naturally occurring non-reducing disaccharide, is known to act as a major protein stabilizer that can reduce ultraviolet B (UVB)-induced corneal damage when topically applied to the eye. However, due to the low skin permeability of trehalose, which makes the development of topical formulations difficult, its use as a skin photoprotective agent has been limited. Previous findings demonstrated that liposomes may significantly improve the intracellular delivery of trehalose. Therefore, the present study aimed to assess the protective effects of trehalose-loaded liposomes against UVB-induced photodamage using the immortalized human keratinocyte cell line, HaCaT. The effects were also compared to those of the common skin photoprotective compounds, including L-carnosine, L-(+)-ergothioneine, L-ascorbic acid and DL-α-tocopherol. The levels of cyclobutane pyrimidine dimers, 8-hydroxy-2'-deoxyguanosine and protein carbonylation in HaCaT cells were used as biological markers of UVB-induced damage. Compared to other compounds, trehalose-loaded liposomes showed the highest efficacy in reducing the levels of the three markers following UVB irradiation of HaCaT cells (all P

Chronic ultraviolet radiation (UV-R) exposure causes skin disorders like erythema, edema, hyperpigmentation, photoaging and photocarcinogenesis. Recent research trends of researchers have focused more attention on the identification and use of photo stable natural agents with photoprotective properties. Piperine (PIP), as a plant alkaloid, is an important constituent present in black pepper (Piper nigrum), used widely in ayurvedic and other traditional medicines and has broad pharmacological properties. The study was planned to photoprotective efficacy of PIP in human keratinocyte (HaCaT) cell line. We have assessed the UV-R induced activation of transcription factor NF-κB in coordination with cell death modulators (Bax/Bcl-2 and p21). The LC-MS/MS analysis revealed that PIP was photostable under UV-A/UV-B exposure. PIP (10μg/ml) attenuates the UV-R (A and B) induced phototoxicity of keratinocyte cell line through the restoration of cell viability, inhibition of ROS, and malondialdehyde generation. Further, PIP inhibited UV-R mediated DNA damage, prevented micronuclei formation, and reduced sub-G1 phase in cell cycle, which supported against photogenotoxicity. This study revealed that PIP pretreatment strongly suppressed UV-R induced photodamages. Molecular docking studies suggest that PIP binds at the active site of NF-κB, and thus, preventing its translocation to nucleus. In addition, transcriptional and translational analysis advocate the increased expression of NF-κB and concomitant decrease in IkB-α expression under UV-R exposed cells, favouring the apoptosis via Bax/Bcl-2 and p21 pathways. However, PIP induced expression of IkB-α suppress the NF-κB activity which resulted in suppression of apoptotic marker genes and proteins that involved in photoprotection. Therefore, we suggest the applicability of photostable PIP as photoprotective agent for human use.

Extracts of the tropical fern Phlebodium complex of Polypodiaceae family, appear to possess beneficial properties for the skin, attributed to the presence of numerous compounds within the extract that have antioxidant and photoprotective properties. Orally administered Phlebodium complex may provide protection against the detrimental photoaging effects of sunlight, can help reduce the frequency and severity of polymorphous light eruption, and is beneficial for the prevention and potential treatment of several aesthetically relevant conditions. The purpose of this review is to describe beneficial role of Phlebodium complex as an adjunct treatment for vitiligo, melasma, and post-inflammatory hyper-pigmentation. Various extracts applied topically or taken orally have shown several beneficial antioxidant, photo-protectant, anti-mutagenic, and immunoregulatory effects. Modern studies have evaluated the efficacy of Phlebodium extracts as a photoprotective agent and for use in several photo-aggravated dermatologic disorders such as polymorphous light eruption, photodermatoses, vitiligo, melasma, psoriasis, atopic dermatitis, and more recently, in minimizing infections in high-performance athletes. It is these multiple mechanisms of action, in combination with a favorable side effect profile, which make Phlebodium complex a promising adjunctive treatment for several dermatologic disorders. Aerial part has proved to exert antioxidant, photo-protective and immunomodulatory activities; extract of fronds is a natural mixture of phytochemicals endowed with powerful antioxidant properties as flavonoids compared to rhizome. Phlebodium fern extract of fronds and rhizome blocked the deleterious effect of UV irradiation in vitro and in vivo as a natural photoprotectant and potential adjuvant to phototherapy of various skin diseases.

Artocarpin, a prenylated flavonoid isolated from an agricultural plant Artocarpus communis, has been documented to possess anti-inflammation and anticancer activities. As oxidative stress and inflammation promote the development of ultraviolet B (UVB) irradiation-induced photodamage, the aim of the present study was to evaluate the photoprotective effect of artocarpin on UVB-induced skin damage in hairless mice. Artocarpin at a topical dose of 0.05% and 0.1% showed a significant photoprotective effect by decreasing histopathological changes, such as desquamation, epidermal thicken and sunburn cell formation, but 0.1% of artocarpin administration did not show better effect. Regarding the antioxidant activities, artocarpin exhibited a significant effect (P

Ferulic acid (FA) is an antioxidant and photoprotective agent used in biomedical and cosmetic formulations to prevent skin cancer and senescence. Although FA exhibits numerous health benefits, physicochemical instability leading to decomposition hinders its efficacy. To minimize inherent decomposition, a FA-containing biodegradable polymer was prepared via solution polymerization to chemically incorporate FA into a poly(anhydride-ester). The polymer was characterized using nuclear magnetic resonance and infrared spectroscopies. The molecular weight and thermal properties were also determined. In vitro studies demonstrated that the polymer was hydrolytically degradable, thus providing controlled release of the chemically incorporated bioactive with no detectable decomposition. The polymer degradation products were found to exhibit antioxidant and antibacterial activity comparable to that of free FA, and in vitro cell viability studies demonstrated that the polymer is noncytotoxic toward fibroblasts. This renders the polymer a potential candidate for use as a controlled release system for skin care formulations.

Fingerroot [Boesenbergia pandurata (Roxb.) Schltr.], belonging to Zingiberaceae, is an edible tropical medicinal plant that has been traditionally used to treat various diseases. However, the effect of its oral intake on skin has not yet been reported. This study aimed to investigate anti-photoaging effects of the ethanol extract of fingerroot in a hairless mouse model. Compared with the untreated UVB control group, mice that received fingerroot extract (BPE) showed significantly reduced wrinkle formation, skin thickening, and transepidermal water loss in dorsal skin irradiated with UVB. Moreover, BPE significantly prevented UVB-induced matrix metalloproteinase (MMP)-3 and -13 expressions and also MMP-2 and -9 activities. These results strongly suggest that oral administration of BPE confers in vivo anti-photoaging effects in hairless mice. Thus, fingerroot may have potential as an oral photoprotective agent to prevent skin photoaging following UV exposure.

Ultraviolet (UV) radiation, particularly ultraviolet A (UVA), is known to play a major role in photoaging of the human skin. Many studies have demonstrated that UV exposure causes the skin cells to generate reactive oxygen species and activates the mitogen-activated protein kinase (MAPK) pathway. Previous studies have also demonstrated that cycloheterophyllin has an antioxidant effect and can effectively scavenge free radicals. Extending the aforementioned investigations, in this study, human dermal fibroblasts were used to investigate the protective effect of cycloheterophyllin against UV-induced damage. We found that cycloheterophyllin not only significantly increased cell viability, but also attenuated the phosphorylation of MAPK after UVA exposure. Furthermore, cycloheterophyllin could reduce hydrogen peroxide (H2O2) generation and down-regulate H2O2-induced MAPK phosphorylation. In the in vivo studies, the topical application of cycloheterophyllin before UVA irradiation significantly decreased trans-epidermal water loss (TEWL), erythema, and blood flow rate. These results indicate that cycloheterophyllin is a photoprotective agent that inhibits UVA-induced oxidative stress and damage, and could be used in the research on and prevention of skin photoaging.

Photoageing resulting from long term exposure of the skin to UV light can be minimized by scavenging the reactive photochemical intermediates with antioxidants. For effective photoprotection, the antioxidant must overcome the barrier properties of the skin and reach the target site in significant amounts. The present study aims to improve the skin penetration of caffeic acid, a very effective free radical scavenger, by encapsulating in liposomes. Caffeic acid loaded liposomes prepared using the reverse phase evaporation technique showed 70% encapsulation efficiency and size around 100 nm with zeta potential of −55 mV. $\textit{In vitro}$ diffusion through a dialysis membrane enabled 70% release of encapsulated caffeic acid within 7 h, whereas 95% of free caffeic acid diffused within 4 h in PBS solution (pH 7.4). Liposomal caffeic acid permeation through pig skin epidermis in a Franz cell apparatus was 45 % during 7 h. In contrast, free caffeic acid was almost nonpermeable (, This research was financially supported by the HETC QIG Win 3 grant, University of Peradeniya, Peradeniya, Sri Lanka.

This chapter discusses the finishing of technical textiles by both chemical and mechanical processes with some reference to future finishes.

Summary Background Ultraviolet B generates reactive oxygen species by interacting with water in irradiated skin tissues and cells in turn causes lipid peroxidation, protein modification and further DNA damage. Purpose This study examined the cytoprotective effects of phloroglucinol (1,3,5-trihydroxybenzene) on ultraviolet B-irradiated cultured human keratinocytes. Methods The human keratinocyte cell line HaCaT cells were treated with 10 μM of phloroglucinol. After 1 h, the cells were irradiated with ultraviolet B light at 30 mJ/cm2 and incubated at 37°C. Results Phloroglucinol scavenged both the superoxide anion and hydroxyl radical in a cell-free system and ultraviolet B-induced intracellular reactive oxygen species. Phloroglucinol reduced ultraviolet B-generated lipid peroxidation, protein modification and DNA strand breaks. The enzymatic effects of phloroglucinol restored cellular glutathione levels, superoxide dismutase and catalase activities, which were impaired by ultraviolet B radiation. Conclusion: Phloroglucinol provides the protective effects in human keratinocyte cell line exposed to ultraviolet B radiation, suggesting that phloroglucinol can be used as a photoprotective agent.

Background UV radiation and the presence of melanocytic nevi are the main risk factors of sporadic melanoma (MM). Protection of skin by an oral photoprotective agent would have substantial benefits. Objective We investigated the possible role of an oral Polypodium leucotomos (PL) extract to improve systemic photoprotection in patients at risk of skin cancer analyzing the ability to decrease UV-induced erythema. We also studied the interaction among MC1R polymorphisms and CDKN2A status with the minimal erythematous dose (MED) and their influence in the response after oral PL. Methods A total of 61 patients (25 with familial and ⁄ or multiple MM, 20 with sporadic MM and 16 with atypical mole syndrome without history of MM) were exposed to varying doses of artificial UVB radiation without and after oral administration of a total dose of 1080mg of PL. Results Oral PL treatment significantly increased the MED mean in all group patients (0.123 to 0.161 J ⁄ cm 2 , p

Probiotics are live micro-organisms that when administered in adequate amounts confer a health benefit on the host. Cell surface molecules of these micro-organisms are being studied in relation to their ability to interact with the host. The cell wall of lactobacilli possesses lipoteichoic acids (LTA) which are molecules with immunomodulatory properties. UV radiation (UVR) has been proposed as the main cause of skin cancer because of its mutagenic and immunosuppressive effects. Photoprotection with some nutrition interventions including probiotics has recently been shown. The aim of the present study was to investigate whether the oral administration of purified LTA from Lactobacillus rhamnosus GG can modulate the immune-suppressive effect of UVR and skin tumour development in female Crl:SKH-1-hrBR mice. For this purpose, two irradiation models were studied: (1) a chronic irradiation scheme consisting of daily irradiations during twenty consecutive days and (2) a long-term irradiation schedule, irradiating the animals three times per week, during 34 weeks for tumour development. The results showed that T-cells in the inguinal lymph node of LTA-treated mice produced higher levels of (1) interferon-γ and (2) a number of total, helper and cytotoxic T-cells compared with non-treated mice. Moreover, a significant delay in tumour appearance was found in LTA-treated mice. An increased IgA+ cell number was found in the small intestine together with a higher number of activated dendritic cells in the mesenteric lymph nodes. The latter results might be indicative of a direct effect of LTA in the gut, affecting the cutaneous immune system and restoring homeostasis through the gut–skin axis. Fil: Weill, Federico S.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia,inmunologia y Biotecnolog.. Catedra de Inmunologia; Argentina Fil: Cela, Eliana Maiten. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia,inmunologia y Biotecnolog.. Catedra de Inmunologia; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral "Profesor R. A. Margni"; Argentina Fil: Paz, Mariela Laura. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia,inmunologia y Biotecnolog.. Catedra de Inmunologia; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral "Profesor R. A. Margni"; Argentina Fil: Ferrari, Alejandro. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia,inmunologia y Biotecnolog.. Catedra de Inmunologia; Argentina Fil: Leoni, Juliana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia,inmunologia y Biotecnolog.. Catedra de Inmunologia; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral "Profesor R. A. Margni"; Argentina Fil: Gonzalez Maglio, Daniel Horacio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia,inmunologia y Biotecnolog.. Catedra de Inmunologia; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral "Profesor R. A. Margni"; Argentina

There is an increasing interest in the use of natural antioxidants as photoprotective agents against skin damages produced by ultraviolet radiation. The aim of our study was to investigate the protective effect of a Calluna vulgaris extract in human keratinocytes (HaCaT) exposed to ultraviolet B (UVB) radiation. HaCaT cells were treated with C. vulgaris extract 30 minutes prior to irradiation with UVB. The protective effect was evaluated by assessing cell viability using tetrasolium salt (MTT) assay; the generation of lipid peroxides was evaluated using malondialdehide assay (MDA); and DNA damage was evaluated using the comet assay and the quantification by ELISA of specific DNA photolesions [i.e., cyclobutane-pyrimidine dimers (CPDs) and 6-4 photoproducts (6-4PPs)]. After irradiation with cytotoxic doses of UVB (300 and 500 mJ/cm(2)), HaCaT cells pretreated with C. vulgaris extract (50 μg GAE/ml) showed significantly increased viability compared to control cells exposed to UVB only. Irradiation alone increased MDA levels in a dose-dependent fashion. Pretreatment with 12 μg GAE/ml extract lowered MDA levels both at 100 mJ/cm(2) (ρ

Chronic exposure to ultraviolet radiation (UVR) induces skin tumors in hairless mice. Daily oral administration of a Polypodium leucotomos (PL) extract significantly delayed tumor development in PL-treated versus non-PL-treated mice. UVR and/or PL treatment modified several oxidative stress markers. In all irradiated mice, erythrocytic glutathione S-transferase (GST) activity and glutathione disulphide (GSSG) content increased and in all PL-treated mice GSSG content decreased, specially in non-irradiated animals, and total plasma anti-oxidant capacity (ORAC) increased. In dorsolateral non-tumoral skin of all irradiated mice, glutathione reductase (GR) and glutathione peroxidase (GPx) activities increased and GSSG decreased in non-irradiated PL-treated animals. UVR induced a steep increase of p53 expression in epidermal cells. In non-tumoral skin, this increase was significantly higher in PL-treated animals than in non-treated mice and can contribute in delaying tumor development, either by repairing the damaged DNA or by increasing apoptosis. These results reinforce the usefulness of PL as systemic photoprotective agent, especially in patients highly sensitive to UVR.

Skin whitening with Chinese herbal medicine has been used in ancient Asia. However, phototoxicity of the active ingredient limits the application. The modified comet assay was used in the current study to detect DNA crosslinking induced by phototoxicity. Result showed that caffeine at 5 µmol/L was able to reduce 5-methoxypsoralen-induced phototoxicity with ultraviolet C (UVC) exposure.

The insecticidal activity after field exposure of an aluminum-carboxymethylcellulose microencapsulated formulation of Bacillus thuringiensis israelensis (Bti) spore-toxin complex, with malachite green as photoprotective agent, was evaluated using third-instar Aedes aegypti (L.) larvae in laboratory bioassays in Veracruz, Mexico. Four insecticide treatments and an untreated control were compared at low and high doses over 96 d of field exposure under full sun or full shade conditions: 1) microencapsulated Bti spore-toxin complex, 2) nonmicroencapsulated Bti spore-toxin complex, 3) a commercial Bti formulation, 4) a commercial formulation of temephos, and 5) an untreated control. The low and high doses corresponded to the LC50 and LC90 concentrations for the Bti insecticides and to 0.5 and 1.0 mg/liter for temephos; the corresponding values for the microencapsulated Bti and commercial Bti, estimated in this study, were 0.061 and 0.14 mg/ml and 0.13 and 0.30 mg/ml, respectively. Overall, the study demonstrated that microencapsulation with aluminum-carboxymethylcellulose improved the activity against Ae. aegypti larvae of B. t. israelensis spore-toxin complex over that of a nonmicroencapsulated spore-toxin complex and that the improvement was particularly important under full sun and high dose. Moreover, insecticidal activity of the microencapsulated B. thuringiensis israelensis spore-toxin complex was superior to that of a commercial B. thuringiensis israelensis formulation and comparable to that of the chemical insecticide temephos. Finally, it was suggested that the microencapsulated B. thuringiensis israelensis formulation should be evaluated for field use in Veracruz because its activity against Ae. aegypti larvae remained high through 31 d and this would allow halving of the current insecticide application frequency.

Photoprotection is essential to prevent the deleterious effects of ultraviolet (UV) light, including skin cancer, photoaging and immunosuppression. Photoprotective agents can be classified according to their main mechanism of action. Some of them absorb or deflect UV photons (sunscreens), whereas others prevent or fix the deleterious effects of UV exposure. Here, we review recent evidence on the cellular and molecular mechanisms underlying the photoprotective effect of a Polypodium leucotomos fern extract (PL). PL is a natural mixture of phytochemicals endowed with powerful antioxidant properties. Its short-term effects include inhibition of reactive oxygen species production induced by UV radiation, DNA damage, isomerization and decomposition of trans-urocanic acid, prevention of UV-mediated apoptosis and necrosis, as well as degradative matrix remodeling, which is the main cause of photoaging. These short-term effects translate into long-term prevention of photoaging and photocarcinogenesis. A striking property is that PL can exert its effect when administered orally. Together, these effects postulate PL as a natural photoprotective agent and a potential adjuvant to phototherapy for various skin diseases.

UVB exposure of skin results in various biologic responses either through direct or indirect damage to DNA and non-DNA cellular targets via the formation of free radicals, reactive oxygen species (ROS) and inflammation. Bucillamine [N-(2-mercapto-2-methylpropionyl)-l-cysteine] is a cysteine-derived compound that can replenish endogenous glutathione due to its two donatable thiol groups, and functions as an antioxidant. In this study, we investigated the effects of bucillamine on UVB-induced photodamage using the SKH-1 hairless mouse model. We have demonstrated that UVB exposure (two consecutive doses, 230 mJ cm(-2)) on the dorsal skin of SKH-1 mice induced inflammatory responses (edema, erythema, dermal infiltration of leukocytes, dilated blood vessels) and p53 activation as early as 6 h after the last UVB exposure. Bucillamine pretreatment (20 mg kg(-1) of body weight, administered subcutaneously) markedly attenuated UVB-mediated inflammatory responses and p53 activation. We have also demonstrated that the stabilization and upregulation of p53 by UVB correlated with phosphorylation of Ser-15 and Ser-20 residues of p53 protein and that bucillamine pretreatment attenuated this effect. We propose that bucillamine has potential to be effective as a photoprotective agent for the management of pathologic conditions elicited by UV exposure.

Aims: To isolate a bacterium that produces high yield of melanin and to examine the effect of this bacterial pigment on the efficacy of a bioinsecticide. Methods and Results: A novel melanin-producing bacterium, designated as strain WS, was isolated from the East Lake, Wuhan, China. Taxonomic studies of this strain indicate that it belongs to Aeromonas media. Physicochemical analysis of the pigment produced by strain WS (melanin WS) suggests that it is the authentic 3,4-dihydroxyphenylalanine (DOPA)-melanin. This melanin and that produced by Pseudomonas maltophilia P28 (melanin P28) share many biophysical properties, but the yield of the melanin WS is significantly higher than that of the melanin P28. In addition, the melanin WS appears to be more effective in the protection of a bioinsecticide against ultraviolet (UV) or solar radiation. At the concentration of 10 ppm, the melanin P28 exhibited no photoprotective effect on the bioinsecticide against UV radiation; in contrast, 5 ppm of melanin WS displayed an obvious protective effect. Similarly, the melanin WS displayed more protective effect on the bioinsecticide against solar radiation than the melanin P28 did over a 4-day period, with the effect being more dramatic for the last 2 days. Conclusions: We have isolated a novel bacterial strain of A. media that produces high levels of melanin. The melanin produced by this strain offers effective photoprotection of a commercial bioinsecticide BTI against UV and solar radiation. Significance and Impact of the Study: Our study suggests that the melanin produced by our newly isolated A. media strain has the potential to be used as a general photoprotective agent for bioinsecticides.

SummaryUltraviolet-B (UVB) irradiation induced the synthesis of matrix metalloproteinase–1 (MMP–1) and stromelysin–1 (MMP–3) in skin fibroblasts, causing skin photoaging and skin tumor progression. The effect of honey bee venom (HBV) collected from Apis mellifera on the expression of MMP–1 and MMP–3 in UVB irradiated human dermal fibroblasts (HDF) was investigated. After UVB irradiation, HBV markedly reduced UV-induced MMP–1 by 50–80% and MMP–3 protein levels by 50–85 % compared with that of UVB-irradiated controls. It also reduced MMP–1 and MMP–3 mRNA expression. Furthermore, HBV accelerated the recovery of the damaged of UVB-irradiated HDF. These results suggest that HBV is a photoprotective agent and could be used as a potential agent in preventing photoaging.

A new molecule, LQFM048, originally designed through molecular hybridization using green chemistry approach, is in development as a photoprotective agent. Eye irritation, skin toxicity and genotoxicity evaluations are mandatory for predicting health risks. In this context, the purpose of this study was to investigate the eye irritation potential of LQFM048 by combining Short Time Exposure (STE), Bovine Corneal Opacity and Permeability (BCOP) associated with corneal histomorphometry and Hen's Egg Test-Chorioallantoic Membrane (HET-CAM). Additionally, skin toxicity was evaluated by interleukin-18 production in the HaCaT keratinocyte, Local Lymph Node Assay (LLNA:BrdU-ELISA) method, 3T3 Neutral red uptake (NRU) assay and in vivo phototoxicity test. Genotoxic potential of LQFM048 was also analyzed by cytokinesis-block micronucleus assay (MNvit test-cytoB) in HepG2 cells. Our results showed that LQFM048 did not induce eye irritation and it was classified as UN GHS No Category for both STE and BCOP assays and non-irritating for HET-CAM test. LQFM048 showed non-potential skin sensitization with stimulation index (SI=0.7) in the LLNA:BrdU-ELISA method. Corroborating in vivo tests, it did not promote significant cytotoxicity in HaCaT cells and it showed similar levels of IL-18 when compared to control. Furthermore, LQFM048 induced non-phototoxic potential with photo-irritation factor (PIF) and mean photo effect (MPE) of 1 and -0.138, respectively, for 3T3 cells. Similarly, it was not phototoxic for in vivo testing with or without exposure to UVA, showing SI values of 1 and 1.2, respectively. The micronucleus test showed that LQFM048 was not genotoxic, under the conditions tested.In conclusion, LQFM048, a heterocyclic compound obtained through an environmentally acceptable simple synthetic route, seems to be safe for human use, especially for the development of a new sunscreen product, since it is neither an eye irritant, nor a contact allergen, nor mutagenic and nor phototoxic.

OBJECTIVE Epigallocatechin-3-gallate (EGCG) is the physiologically most active and abundant flavanol, accounting for 50-80% of green tea catechins. It is an anti-inflammatory, antioxidant, chemopreventive and skin photoprotective agent. However, light sensitivity and low permeability of EGCG across the stratum corneum due to its high molecular weight as well as strong binding to the lipid bilayers in the skin make it difficult to be used as a key ingredient in cosmetic products. This study aimed to formulate a photostable hydrogel of EGCG with good rheological properties for dermal application and investigate the effect of skin microporation using maltose microneedles on its permeation through dermatomed porcine skin. METHODS Effect of l-glutathione on photodegradation of EGCG was investigated by exposing samples to ultraviolet irradiation for 1 h using a solar simulator. Hydrogels with varying concentrations of Carbopol 980 (0.5-2% w/v) as an gelling agent were prepared, and their rheological properties were evaluated using a rheometer. Skin microporation was confirmed by assessing the skin resistance, transepidermal water loss and calcein imaging of the microchannels created by the microneedles. Permeation of EGCG from aqueous solution as well as the rheologically optimized hydrogel through the dermatomed porcine skin (untreated and microneedle treated) was evaluated using static vertical Franz diffusion cells. RESULTS l-glutathione acting as a co-antioxidant and photostabilizer significantly (P < 0.05) reduced the degradation of EGCG from 21.53 ± 2.78% to 1.0 ± 0.68% after 1 h of ultraviolet irradiation. Rotational and oscillatory rheological tests indicated that the hydrogel containing 1.5% Carbopol 980 is acceptable for topical application in terms of flow behaviour, elasticity, spreadability, structural stability and thixotropy. Microneedle-treated skin showed significant enhancement (P < 0.05) in the delivery of EGCG to viable epidermis and dermis from the aqueous solution (38.67 ± 2.96 μg cm(-2) ) as well as hydrogel (24.60 ± 2.62 μg cm(-2) ) in comparison with the untreated skin (24.16 ± 2.11 and 15.62 ± 0.24 μg cm(-2) for aqueous solution and hydrogel, respectively). CONCLUSION Addition of glutathione in EGCG formulations significantly reduces its photodegradation. Skin microporation with maltose microneedles facilitates the penetration of EGCG across the stratum corneum into the deeper skin layers - viable epidermis and dermis.

Background and aims. The depletion of the ozone layer allows overexposure of the skin to UV radiation, which is prolonged due to the increasing life expectancy, together with inappropriate life habits contribute to the increasing incidence of cutaneous malignancies. Plant extracts with antioxidant capacities are frequently employed as a means to protect skin against ultraviolet (UV) radiations, thus preventing skin cancers. In the present study we assessed a red grape seed extract (GSE) potential capacities to reduce ultraviolet B (UVB) radiation-induced reactive oxygen species (ROS) and subsequent apoptosis in a human keratinocytes cell line (HaCaT). We identified molecules and pathways modulated by the GSE through which this may exert its photoprotective effect. Methods. The GSE was standardized according to its polyphenolic content and the most important biologically active compounds, such as epigallocatechin and epicatechin, catechin hydrate, procyanidin B and gallic acid were evidenced by high-performance liquid chromatography. According to the plant extract cytotoxicity on the HaCaT cell line, two concentrations were selected for testing from the non-toxic range: GSE 1 (37.5 μgEqGA/ml) and GSE 2 (75 μgEqGA/ml). The level of ROS was evaluated with CM-H 2 DCFDA assay, while apoptosis, Bax-α and NF-kβ p65 proteins with ELISA and confirmed by western-blot. Results. Both concentrations of the extract decreased the level of ROS in UVB-irradiated keratinocytes (p

Archaeological indicators of cognitive complexity become increasingly prevalent during the African Middle Stone Age, with the habitual exploitation of red ochre widely viewed as a key feature of the emergence of modern human behaviour. Given that some of the uses of ochre remain ambiguous, we present the preliminary results of an ongoing study in which we explore the efficacy of red ochre as a photoprotective device or sunscreen. The capacity of ochre to inhibit the susceptibility of humans to the detrimental effects of ultraviolet radiation was confirmed through the in vitro calculation of the sun protection factor values of samples derived from the Kunene Region in Namibia and the Bokkeveld Group deposits, Western Cape Province, South Africa. Visible spectroscopy was employed to determine colourimetric parameters of samples and assess the correlation between ochre colour and sun protection factor. The possible role of ochre as a sunscreen agent for hominin populations, including modern humans, during the Middle Stone Age in Africa is explored. We conclude that the habitual use of red ochre as a photoprotective agent likely played a role in the ability of prehistoric humans to adapt to novel environmental circumstances.

Previously we reported that a polypeptide from Chlamys farreri (PCF) was a potent photoprotective agent against ultraviolet (UV) irradiation in vitro. To understand the mechanism by which PCF protects cells from irradiation, we studied anti-apoptotic effects of PCF against UV irradiation on the murine thymocytes in vitro. MTT and flow cytometric analysis assays showed that 2h pretreatment with PCF completely abolished UV induced cell death. TEM examination showed that PCF fully protected the ultrastructure of thymocytes exposed to UV irradiation. Lipid peroxidation and intracellular reactive oxygen species assays indicated that PCF efficiently blocked production of reactive oxygen intermediates induced by UV irradiation. Further, PCF protected UV-irradiated thymocytes from losing mitochondrial transmembrane potential and DNA fragmentation. Based on these observations we propose that PCF is a potent anti-apoptotic factor, which protects cells from irradiation at multiple steps.

One of the most significant risk factors associated with the development of skin disease is exposure to UVB radiation from the sun. In particular, UVB light can activate inflammatory and apoptotic pathways, leading to skin damage. Anthocyanins, a group of flavonoids present in many common vegetable foods, are known for their chemopreventive activity. The aim of this study was to evaluate the efficacy of cyanidin-3-O-glucoside (C3G) on modulation of cellular responses following exposure to UVB doses in human keratinocytes (HaCaT). In our study, UVB-exposed cells showed significant increase of the translocation of transcription factors NF-kB and AP-1, overexpression of the proinflammatory cytokine IL-8, cleavage of procaspase-3 (a key step in apoptotic pathway), and DNA fragmentation. All these effects elicited by UVB exposure were clearly inhibited by pretreating HaCaT cells with C3G. In conclusion, our data demonstrate that C3G can protect skin cells against the adverse effects of UVB radiation and suggest that it might successfully be employed as a skin photoprotective agent.

Synopsis A new experimental design, more reliable for in vitro testing of active ingredients' effect on ultraviolet (UV)-induced melanogenesis has been carried out. It uses a bicompartmental coculture system where cell communication between keratinocytes and melanocytes can take place. Thus, this experimental situation enables to monitor the effect of biological agents released by both cell types on melanogenesis and the interference of tested compounds with this ‘paracrine linkage’. Experiments with UVB-irradiated cocultures show the importance of cell communication in the melanogenic response. In this model, the endogenous mediator, nitric oxide (NO), increased melanin production. Different compounds were tested in the coculture system, and comparison with data obtained from irradiated monocultures of melanocytes enables to distinguish a specific effect on cell communication. In addition, this more close-to-reality experimental model proved to provide a valuable first approach for the assessment of the ‘bioavailability’ of the tested substances. Finally, the effect of an innovative photoprotective agent capable of ‘boosting’ UV-induced melanogenic cell communication is presented.

Cutaneous photodamage is partly mediated via oxidative pathways and there is evidence to suggest that antioxidants within the skin may have a photoprotective effect. Antioxidant activity is provided by a number of naturally occurring substances including alpha-tocopherol (vitamin E) and beta-carotene, whose effects are mediated by their capacity to quench singlet oxygen, scavenge free radicals and prevent the formation of free radicals. Beta-carotene has been used as treatment for various photosensitivity disorders for more than 30 years. The main indication for its use is in the treatment of the photosensitivity associated with erythropoietic protoporphyria. A role for beta-carotene in the prevention of non-melanoma skin cancer has yet to be demonstrated despite clinical research activity in this area. The role for alpha-tocopherol as a photoprotective agent is less clear-cut and it has yet to be established as treatment either for conditions characterized by photosensitivity or as an agent for preventing chronic photodamage or cutaneous malignancy.

The aim of the study was to examine the effect of topical vehicles on the in vivo human stratum corneum penetration of the antioxidant and skin photoprotective agent (-)-epigallocatechin-3-gallate (EGCG). Model oil-in-water (o/w) emulsion and gel formulations containing 1 % (m/m) EGCG were prepared and subjected to photodegradation studies in order to select excipients that minimize the light instability of EGCG. The optimized emulsion and gel were applied to human volunteers and the EGCG percutaneous permeation was evaluated in vivo by the tape- -stripping technique. No significant differences in the percentage of the applied EGCG dose diffused into the stratum corneum were observed between the o/w emulsion (36.1 ± 7.5 %) and gel (35.5 ± 8.1 %) preparations. However, the amount of EGCG permeated into the deeper region of human stratum corneum was significantly larger for the o/w emulsion compared to the gel. Therefore, the emulsion represents a suitable vehicle for topical delivery of EGCG.