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Mostefa Lefahal, Nabila Zaabat, Radia Ayad, El Hani Makhloufi, Lakhdar Djarri, Merzoug Benahmed, Hocine Laouer, Gema Nieto, Salah Akkal
Background: Capnophyllum peregrinum (L.) Lange (Apiaceae) is the unique taxon of capnophyllum genus in Algerian flora. It has never been investigated in regards to its total phenolic and flavonoid contents and antioxidant and photoprotective activities. Methods: C. peregrinum aerial parts extracted with absolute methanol. The total flavonoid and phenolic contents of the extract were evaluated to determine their correlation with the antioxidant and photoprotective activities of the extract. Results: The methanolic extract demonstrated a significant amount of phenolics and flavonoids (74...
March 22, 2018: Medicines (Basel, Switzerland)
Alena Rajnochová Svobodová, Eva Gabrielová, Loizos Michaelides, Pavel Kosina, Alena Ryšavá, Jitka Ulrichová, Bohumil Zálešák, Jitka Vostálová
Exposure to solar radiation is a major cause of environmental human skin damage. The main constituent of solar UV light is UVA radiation (320-400 nm); however, the need for protection against UVA has been marginalized for a long time. As a result, there is still a lack of useful agents for UVA protection. In this study, the effect of silymarin (SM) and its main constituent silybin (SB) pre-treatment on UVA-stimulated damage to primary human dermal fibroblasts were carried out. The cells were pre-treated for 1 h with SB or SM and then were exposed to UVA light, using a solar simulator...
March 21, 2018: Archives of Dermatological Research
Adele Repossi, Elisa Zironi, Teresa Gazzotti, Andrea Serraino, Giampiero Pagliuca
Vitamin B12 (cobalamin) is a metal complex composed of a central cobalt ion bonded to six ligands. It is essential for major biological functions such as protein, fat and carbohydrate metabolism, the maintenance of the central nervous system, and the formation of red blood cells. Since mammals cannot synthesize cobalamin, dietary intake represents the only natural source for humans. Dairy products can provide significant levels of cobalamin; moreover, the European Food Safety Authority (EFSA) panel has set the recommended intake at 4 μg/day for adults...
October 20, 2017: Italian Journal of Food Safety
Tanai Cardona
When and how oxygenic photosynthesis originated remains controversial. Wide uncertainties exist for the earliest detection of biogenic oxygen in the geochemical record or the origin of water oxidation in ancestral lineages of the phylum Cyanobacteria. A unique trait of oxygenic photosynthesis is that the process uses a Type I reaction centre with a heterodimeric core, also known as Photosystem I, made of two distinct but homologous subunits, PsaA and PsaB. In contrast, all other known Type I reaction centres in anoxygenic phototrophs have a homodimeric core...
March 2018: Heliyon
Claudia Salomone B, Isabel Ogueta C, Carlos Reyes V, Gloria Durán S, Noemí Aguirre, Angélica Wietstruck
Congenital erythropoietic porphyria is an extremely rare, autosomal recessive, non-acute cutaneous porphyria, caused by uroporphyrinogen III synthase deficiency, codificated by UROS gene on the chromosome 10q26.2. Porphyrins deposit in cornea, bones and teeth. The first symptoms could be manifested in early childhood, with skin fragility, vesicles and bullae. Severe course produces acral tissues mutilation, eye involvement, hemolytic anemia and hypersplenism. The treatment is complex and it is based in the photoprotection...
April 1, 2018: Archivos Argentinos de Pediatría
Umar Muzaffer, V I Paul, Nagarajan Rajendra Prasad, Ramasamy Karthikeyan
The present study was aimed to investigate the photoprotective effect of the male flower of J. regia L. (MEJR) against ultraviolet-B induced apoptosis in human skin cells. Human skin epidermal keratinocytes were pretreated with the MEJR (80 µg/ml, has been selected after MTT assay), prior to 30 min UVB-irradiation at a dose of 20 mJ/cm2 . Mitochondrial membrane potential was evaluated using Rhodamine-123 staining; the % apoptosis by Hoechst staining and acridine orange staining; DNA damage was measured by comet assay...
March 2018: Biochemistry and Biophysics Reports
Kotaro Kosuge, Ryutaro Tokutsu, Eunchul Kim, Seiji Akimoto, Makio Yokono, Yoshifumi Ueno, Jun Minagawa
Photosynthetic organisms are frequently exposed to light intensities that surpass the photosynthetic electron transport capacity. Under these conditions, the excess absorbed energy can be transferred from excited chlorophyll in the triplet state (3Chl*) to molecular O2 , which leads to the production of harmful reactive oxygen species. To avoid this photooxidative stress, photosynthetic organisms must respond to excess light. In the green alga Chlamydomonas reinhardtii , the fastest response to high light is nonphotochemical quenching, a process that allows safe dissipation of the excess energy as heat...
March 19, 2018: Proceedings of the National Academy of Sciences of the United States of America
Isabel Aparici-Espert, Miguel A Miranda, Virginie Lhiaubet-Vallet
Photosensitization by drugs is a problem of increasing importance in modern life. This phenomenon occurs when a chemical substance in the skin is exposed to sunlight. Photosensitizing drugs are reported to cause severe skin dermatitis, and indeed, it is generally advised to avoid sunbathing and to apply sunscreen. In this context, the nonsteroidal anti-inflammatory drug (NSAID) diclofenac is a photosensitive drug, especially when administered in topical form. In this work, efforts have been made to design and study an innovative pro-drug/pro-filter system containing diclofenac and the UVA filter avobenzone in order to develop a safer use of this topical drug...
March 16, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Anna Baldisserotto, Piergiacomo Buso, Matteo Radice, Valeria Dissette, Ilaria Lampronti, Roberto Gambari, Stefano Manfredini, Silvia Vertuani
Moringa oleifera has gained increasing popularity as a food supplement but not in the pharmaceutical and cosmetic area. The aim of this study was the preparation, characterization, and evaluation of extracts from the leaves of Moringa oleifera as a herbal sun care phytocomplex. Three different extracts of Moringa oleifera leaves, from Senegal, have been prepared and chemically characterized in the phenolic fraction by HPLC-DAD and Folin-Ciocalteu test. To explore photoprotective properties, an extensive evaluation of UV filtering, antioxidant (DPPH, FRAP, ORAC, PCL), and anti-hyperproliferative (human melanoma Colo38 cells) capacities have been conducted...
March 15, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
M J Llansola-Portoles, K Redeckas, S Streckaité, C Ilioaia, A A Pascal, A Telfer, M Vengris, L Valkunas, B Robert
Transient absorption studies conducted on in vitro lycopene aggregates, as well as on lycopene crystalloids inside tomato chromoplasts, reveal the appearance of a long-lived excited state, which we unambiguously identified as lycopene triplet. These triplet states must be generated by singlet exciton fission, which occurs from the lycopene2 Ag state. This is the first time the singlet fission process has ever been shown to occur in a biological material. We propose that the formation of carotenoid assemblies in chromoplasts may constitute a photoprotective process during chromoplast maturation, in addition to their function in signaling processes...
March 14, 2018: Physical Chemistry Chemical Physics: PCCP
A Haylett, D Koumaki, L E Rhodes
BACKGROUND: Solar urticaria (SU) is a rare chronic inducible urticaria triggered via uncharacterised chromophores. We detail responses of a large patient series to monochromator phototesting and broadband ultraviolet radiation (UVR); relationship to life quality is explored. METHODS: Retrospective review of all SU patients undergoing standardised diagnostic photoinvestigation at a specialist centre during 2000-2016. From 2011, patients completed dermatology life quality index (DLQI) questionnaires for the past week and year...
March 13, 2018: Photodermatology, Photoimmunology & Photomedicine
Abidullah Khan, Bai Hongliang, Enqi Liu, Chen Mingxia, Yu Chunshui, Rai Wang, Khan Amin, Bai Zhuanli
Studies have shown that skin exposure to ultraviolet radiation (UVR) results in the formation of reactive oxygen species (ROS), thus altering the cellular function. The human epidermal skin layer is mainly composed of keratinocytes, which is damaged by UV-B radiation induced intracellular oxidative stress. Neferine is an alkaloid extract from lotus seed embryos, and its photoprotective action against UV-B produced oxidative damage in human epidermal keratinocytes (HEKs) has never been proposed. Neferine inhibited UV-B mediated increase in ROS and malondialdehyde (MDA) levels in pretreated keratinocytes...
March 13, 2018: Journal of Dermatological Treatment
Yury B Slonimskiy, Eugene G Maksimov, Evgeny P Lukashev, Marcus Moldenhauer, Cy M Jeffries, Dmitri I Svergun, Thomas Friedrich, Nikolai N Sluchanko
Photosynthesis requires a balance between efficient light harvesting and protection against photodamage. The cyanobacterial photoprotection system uniquely relies on the functioning of the photoactive orange carotenoid protein (OCP) that under intense illumination provides fluorescence quenching of the light-harvesting antenna complexes, phycobilisomes. The recently identified fluorescence recovery protein (FRP) binds to the photoactivated OCP and accelerates its relaxation into the basal form, completing the regulatory circle...
March 7, 2018: Biochimica et Biophysica Acta
N N Sluchanko, Y B Slonimskiy, E G Maksimov
Photoprotective mechanisms of cyanobacteria are characterized by several features associated with the structure of their water-soluble antenna complexes - the phycobilisomes (PBs). During energy transfer from PBs to chlorophyll of photosystem reaction centers, the "energy funnel" principle is realized, which regulates energy flux due to the specialized interaction of the PBs core with a quenching molecule capable of effectively dissipating electron excitation energy into heat. The role of the quencher is performed by ketocarotenoid within the photoactive orange carotenoid protein (OCP), which is also a sensor for light flux...
December 2017: Biochemistry. Biokhimii︠a︡
Vivian Saez, Ingrid D L de Souza, Cláudia Regina Elias Mansur
The antioxidative and photoprotective properties of vitamin E have caused it to be included as an active agent in various pharmaceutical and cosmetic products. However, its lipophilicity, chemical instability, and poor skin penetration have limited the effectiveness of these formulations. For that reason, many attempts to include it in different drug delivery systems have been made. In recent decades, lipid nanoparticles have received special attention due to their advantages of compatibility with the skin, ability to enhance penetration of drugs in the stratum corneum, protection of the encapsulated substance against degradation induced by the external medium, and control of drug release...
March 5, 2018: International Journal of Cosmetic Science
Kaori Kohzuma, Kouki Hikosaka
Non-photochemical quenching (NPQ) is the most important photoprotective system in higher plants. NPQ can be divided into several steps according to the timescale of relaxation of chlorophyll fluorescence after reaching a steady state (i.e., the fast phase, qE; middle phase, qZ or qT; and slow phase, qI). The dissipation of excess energy as heat during the xanthophyll cycle, a large component of NPQ, is detectable during the fast to middle phase (sec to min). Although thermal dissipation is primarily investigated using indirect methods such as chlorophyll a fluorescence measurements, such analyses require dark adaptation or the application of a saturating pulse during measurement, making it difficult to continuously monitor this process...
February 28, 2018: Biochemical and Biophysical Research Communications
Liborija Lugović-Mihić, Tomislav Duvančić, Iva Ferček, Petra Vuković, Iva Japundžić, Diana Ćesić
When taking different drugs, their possible side effects on the skin should be considered, including skin reactions connected to photosensitivity. This photosensitivity caused by drugs can appear as phototoxic reactions (which occur more often) or photoallergic reactions (which occur less often and include allergic mechanisms). The following drugs stand out as medications with a high photosensitivity potential: nonsteroidal anti-inflammatory drugs (NSAIDs), cardiovascular drugs (such as amiodarone), phenothiazines (especially chlorpromazine), retinoids, antibiotics (sulfonamides, tetracyclines, especially demeclocycline and quinolones), etc...
June 2017: Acta Clinica Croatica
Dorota Chełminiak-Dudkiewicz, Marta Ziegler-Borowska, Magdalena Stolarska, Lukasz Sobotta, Michal Falkowski, Jadwiga Mielcarek, Tomasz Goslinski, Jolanta Kowalonek, Katarzyna Węgrzynowska-Drzymalska, Halina Kaczmarek
Three magnesium sulfanyl porphyrazines differing in the size of peripheral substituents (3,5-dimethoxybenzylsulfanyl, (3,5-dimethoxybenzyloxy)benzylsulfanyl, 3,5-bis[(3,5-bis[(3,5-dimethoxybenzyloxy)benzyloxy]benzylsulfanyl) were exposed to visible and ultraviolet radiation (UV A + B + C) in order to determine their photochemical properties. The course of photochemical reactions in dimethylformamide solutions and the ability of the systems to generate singlet oxygen were studied by UV-Vis spectroscopy, which additionally gave information on aggregation processes...
February 21, 2018: Journal of Photochemistry and Photobiology. B, Biology
Willem Arend Velema, Anna M Kietrys, Eric T Kool
External photocontrol over RNA function has emerged as a useful tool for studying nucleic acid biology. Most current methods rely on fully synthetic nucleic acids with photocaged nucleobases, limiting application to relatively short synthetic RNAs. Here we report a method to gain photocontrol over RNA by post-synthetic acylation of 2' hydroxyls with photoprotecting groups. One-step introduction of these photocages efficiently blocks hybridization, which is restored after light exposure. Polyacylation (termed cloaking) is further shown to enable photocontrol over a hammerhead ribozyme, illustrating the ability to optically control RNA catalytic function...
February 23, 2018: Journal of the American Chemical Society
Hong-Il Kim, Yong-Un Jeong, Jong-Hyeon Kim, Young-Jin Park
Citrus fruits contain various types of flavonoids with powerful anti-aging and photoprotective effects on the skin, and have thus been attracting attention as potential, efficacious skincare agents. Here, we aimed to investigate the chemical composition of Citrus unshiu and its protective effects on photoaging. We isolated and identified a bioactive compound, 3,5,6,7,8,3',4'-heptamethoxyflavone (HMF), from C. unshiu peels using ethanol extraction and hexane fractionation. HMF inhibited collagenase activity and increased type I procollagen content in UV-induced human dermal fibroblast neonatal (HDFn) cells...
February 22, 2018: International Journal of Molecular Sciences
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