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Oxidative stress induced by medium-wavelength ultraviolet radiation (UVB) is one of the most dangerous environmental stressors for the skin. Therefore, various medicinal remedies aim to prevent the harmful effects of UVB or support the recovery of the damaged cells. This study aimed to evaluate the impact of bioactive phytocannabinoid cannabigerol (CBG) together with 3-O-ethyl ascorbic acid (EAA), a stable, lipophilic derivative of the antioxidant vitamin C, on UVB-induced changes of proteome in cultured human keratinocytes 24 h after treatment. Surprisingly, proteomic analysis revealed very prominent CBG and EAA effects on kinases. These changes mainly influenced ERK1/2, IKK, MAP3K7, MAPK14, RIPK2, and NLK. Their expression was decreased by CBG and EAA, especially if used together after UVB-irradiation, so the effects of UVB were abolished restoring the profile of kinases to non-irradiated control. Moreover, CBG and EAA also reduced the UVB-induced modifications of proteins by the lipid peroxidation product 4-hydroxynonenal, especially in the case of AKT, Camkk1, cJun, ERK1, IKKα, MAPK11 and PERK. We conclude that, by maintaining proteome stability and kinase-dependent signalling, both CBG and EAA may support the recovery of human keratinocytes exposed to UVB radiation, especially if applied together, while the time-dependence of these effects should be further studied. [ABSTRACT FROM AUTHOR]

Phospholipids and their metabolites play an important role in maintaining the membrane integrity and the metabolic functions of keratinocytes under physiological conditions and in the regeneration process after exposure to high-energy UVB radiation. Therefore, in the search for compounds with a protective and regenerative effect on keratinocyte phospholipids, the effectiveness of two antioxidant compounds has been tested: a stable derivative of ascorbic acid, 3-O-ethyl ascorbic acid (EAA) and cannabigerol (CBG), both of which are primarily located in the membrane structures of keratinocytes. In addition, this study has demonstrated that EAA and CBG, especially in a two-component combination, enhance the antioxidant properties of keratinocytes and reduce lipid peroxidation assessed at the level of MDA (malondialdehyde)/neuroprostanes. Moreover, by reducing the activity of enzymes that metabolise phospholipids, free PUFAs (polyunsaturated fatty acids) and endocannabinoids (PLA2; phospholipase A2, COX1/2; cyclooxygenases 1/2, LOX-5; lipoxygenase 5, FAAH; fatty acid amide hydrolase, MAGL; monoacylglycerol lipase), antioxidants have been found to regulate the levels of endocannabinoids (AEA; anandamide, 2-AG; 2-arachidonoylglycerol, PEA; palmitoylethanolamide) and eicosanoids (PGD2; prostaglandin D2, PGE2; prostaglandin E2, 15-d-PGJ2; 15-deoxy-Δ12,14-prostaglandin J2, 15-HETE; 15-hydroxyeicosatetraenoic acid), that are enhanced by UVB radiation. The metabolic effect of both groups of PUFA metabolites is mainly related to the activation of G protein-related receptors (CB1/2; cannabinoid receptor 1 and 2, PPARγ; peroxisome proliferator-activated receptor gamma, TRPV1; transient receptor potential cation channel subfamily V member 1), the expression of which is reduced under the influence of EAA, CBG, and especially the two-component combination. It promotes the regeneration of keratinocyte metabolism disrupted by UVB, particularly in relation to redox balance and inflammation. [ABSTRACT FROM AUTHOR]

Phyllosphere-associated microorganisms must deal with various abiotic stresses such as high-low temperature, low nutrients, and ultraviolet (UV) radiation. These collective actions may trigger the generation of reactive oxygen species (ROS) and causes cellular damage. Cellular defense mechanisms such as morphological changes (size or appearance), production of photo-protectant compounds, and enhancement of antioxidant activities, all of which may contribute to the suppression of ROS and significantly increase survival rates under UV radiation. In this study, five UVB-resistant plant growth-promoting methylotrophs (Methylorubrum thiocyanatum (SD2), Rhodococcus kroppenstedtii (UK3), Methylorubrum populi (KD5), and Methylobacterium brachiatum (KD1 and SD3)) were investigated as adaptive strategies against UVB radiation. Exposure to UVB radiation revealed that methylotrophs changed their morphology to club or dumbbell shapes, and formed biofilm-like structures. Furthermore, Fourier transform-infrared spectroscopy (FTIR) and Gas chromatography-mass spectroscopy (GC–MS) analyses of the methanol-based intracellular extracts of methylotrophs revealed the presence of carotenoids, flavonoids, fatty acids, and antioxidants. Additionally, methylotrophs showed enhanced antioxidant activities such as superoxide dismutase, peroxidase, phenylalanine ammonia-lyase, and proline content with increased UVB exposure (1 -4 h). These findings demonstrate the ability and various adaptation strategies of methylotrophs to survive UVB exposure. These adaptive strategies may be one reason for the promotion of plant growth by methylotrophs under UVB radiation. [ABSTRACT FROM AUTHOR]

Cyanobacterial extracellular polymeric substances (EPS) are secondary metabolites with high physiological importance for survival under ultraviolet radiation (UVR). This is particularly important in drylands, where cyanobacteria are the main components of biological soil crusts (biocrusts), which are subjected to strong natural solar UVB (280–315 nm) irradiation. This research aims to assess the capability of cyanobacteria isolated from biocrusts from Sejzi Plain, Iran, to produce EPS under UVB treatment. Using a top-down approach, two cyanobacterial species were isolated from biocrusts, and identified as Microcoleus vaginatus and Oscillatoria sp. Both taxa were exposed to controlled UVB radiation for 24, 48 and 72 h. Chlorophyll a content, more soluble EPS fraction (loosely bound EPS, LB-EPS), and less soluble EPS fraction (tightly bound EPS, TB EPS) production were measured. M. vaginatus and Oscillatoria sp. produced equal amounts of both EPS under the UVB treatment. A significant relationship was found for decreasing LB-EPS after 24 h of exposure to UVB, while the amount of TB EPS did not decrease, and even increased significantly after 48 and 72 h. The chlorophyll a content of treated cyanobacteria and their control culture was not significantly different. Therefore, under prolonged UVB up to 72 h, these cyanobacteria produced more TB-EPS than LB-EPS. Consequently, TB-EPS might contribute to higher survival under UVB than LB-EPS. [ABSTRACT FROM AUTHOR]

The consumption of vegetables is essential for reducing the risk of noncommunicable diseases, yet global intake falls short of recommended levels. Enhancing the nutraceutical content of vegetables through postharvest abiotic stress, such as ultraviolet B (UVB) radiation, offers a promising solution to increase health benefits. This study developed a user-friendly, at-home UVB device designed to increase the phytochemical content in common vegetables like carrots, lettuce, and broccoli. The device applies UVB radiation (305–315 nm) to fresh-cut vegetables, optimizing exposure time and intensity to maximize nutraceutical enrichment. The results demonstrated that UVB exposure increased the phenolic content by 44% in carrots, 58% in broccoli, and 10% in lettuce, with chlorogenic acid levels rising by 367% in lettuce, 547% in broccoli, and 43% in carrots after 48 h of storage. UVB treatment also enhanced antioxidant activity by up to 41% in broccoli and anti-inflammatory potential by 22% in carrots. In terms of gene expression, UVB treatment upregulated UCP-1 expression by 555% in carrots, enhanced thermogenesis, and increased SIRT-1 and ATGL expression by over 200%, promoting lipid metabolism. This process provides a convenient and efficient method for consumers to boost the health benefits of their vegetables. The study concludes that UVB-induced abiotic stress is an effective strategy to improve vegetable nutritional quality, offering a novel approach to increasing bioactive compound intake and aiding in the prevention of diet-related diseases. [ABSTRACT FROM AUTHOR]

Psoriasis is characterized by excessive exfoliation of the epidermal layer due to enhanced pro-inflammatory signaling and hyperproliferation of keratinocytes, further modulated by UV-based anti-psoriatic treatments. Consequently, this study aimed to evaluate the impact of a lipid extract derived from the microalgae Nannochloropsis oceanica on the proteomic alterations induced by lipid derivatives in non-irradiated and UVB-irradiated keratinocytes from psoriatic skin lesions compared to keratinocytes from healthy individuals. The findings revealed that the microalgae extract diminished the viability of psoriatic keratinocytes without affecting the viability of these cells following UVB exposure. Notably, the microalgae extract led to an increased level of 4-HNE-protein adducts in non-irradiated cells and a reduction in 4-hydroxynonenal (4-HNE)-protein and 15-deoxy-12,14-prostaglandin J2 (15d-PGJ2)-protein adducts in UVB-exposed keratinocytes from psoriasis patients. In healthy skin cells, the extract decreased the UV-induced elevation of 4-HNE-protein and 15d-PGJ2-protein adducts. The antioxidant/anti-inflammatory attributes of the lipid extract from the Nannochloropsis oceanica suggest its potential as a protective agent for keratinocytes in healthy skin against UVB radiation's detrimental effects. Moreover, it could offer therapeutic benefits to skin cells afflicted with psoriatic lesions by mitigating their proliferation and inflammatory responses during UV radiation treatment. [ABSTRACT FROM AUTHOR]

In recent trends, radiation falls under the narrowband ultraviolet‐B region (305–315 nm) widely used in phototherapy lamp applications in the treatment of skin diseases. In this paper, we report a Gd3+‐doped NaYF4 luminescent material synthesized for the first time using the low‐temperature co‐precipitation method. It crystallized into a face‐centred cubic structure, as confirmed by X‐ray diffraction characterization techniques and Rietveld refinement. The photoluminescence property of the as‐prepared sample shows a highly intense, sharp emission band obtained at 311 nm, which belongs to the narrowband ultraviolet‐B region and corresponds to the transition of the 6P7/2→8S7/2 level of the Gd3+ ions under 272 nm excitation (8S7/2 to 6IJ). The transitions of the Gd3+ ions are detected entirely with different concentrations of Gd3+ ions. Scanning electron microscopy analysis indicated that the average particle was 288 nm. The critical distance for energy transfer was calculated to be equal to 11.5017 Å. Dipole–dipole interaction is responsible for energy transfer, as analyzed by Dexter theory. These excellent optical characteristics, together with their highly efficient and low‐cost synthesis approach, indicate that synthesized NaYF4:Gd3+ phosphors have excessive potential for phototherapeutic lamp applications. [ABSTRACT FROM AUTHOR]

In today's evolving global environment, reproductive dysfunctions brought on by various environmental toxins are of greatest concern. Radiation is a constant threat to living things, causing both genetic and cellular changes that result in mutations and cell death. It is thought that ultraviolet B (UVB) radiation we are exposed to daily has biological effects on rats and humans that are both short and long term. Due to the damaging effects of UVB radiation on the living system, this study explores the automatic mechanism by which a certain level of radiation induces oxidative stress, which is further controlled by the antioxidant activity of naringin (NG). In our study, male Swiss albino mice were exposed to UVB irradiation, which altered mice's body and testes weight, hormonal imbalance, biochemical parameters, and histo-morphometric parameter. In addition, we chose naringin's UVB irradiation deterrent effect. Twenty-four healthy adult male Swiss albino mice weighing 25–35 g were chosen at random. For 15 days of exposure, they were divided into four groups at random: group I—control, group II—UVB exposure (2 h per day), group III—UVB exposure with naringin (NG) (80 mg/kg, bw), and group IV—naringin (NG) (80 mg/kg, bw). Compared to the control group, UVB irradiation causes alterations in the animal body weight, testes weight, hormones, enzymatic and non-enzymatic assays, and histological parameters. It was seen that NG retrieved the alterations in parameters caused by UVB irradiation. The UVB radiation exposure on mice caused the testicular dysfunction drastically, while the naringin recapitulates testis functioning. [ABSTRACT FROM AUTHOR]

Methylotrophs are a diverse group of bacteria that abundantly colonize the phyllosphere and have great potential to withstand UV irradiation because of their pigmented nature and ability to promote plant growth through various mechanisms. The present study investigated the effects of UVB radiation on plant growth-promoting (PGP) properties of methylotrophic bacteria and the growth of Vigna radiata L. A total of 55 methylotrophic bacteria were isolated from desert plants, and 15 methylotrophs were resistant to UVB radiation for 4 h. All UVB-resistant methylotrophs possess a methyldehydrogenase gene. Identification based on 16S rRNA gene sequencing revealed that all 15 UVB-resistant methylotrophs belonged to the genera Methylorubrum (07), Methylobacterium (07), and Rhodococcus (01). Screening of methylotrophs for PGP activity in the presence and absence of UVB radiation revealed that all isolates showed ACC deaminase activity and growth on a nitrogen-free medium. Furthermore, the production of IAA-like substances ranged from 8.62 to 85.76 µg/mL, siderophore production increased from 3.47 to 65.75% compared to the control. Seed germination assay with V. radiata L. (mung bean) exposed to UVB radiation revealed that methylotrophs improved seed germination, root length, and shoot length compared to the control. The present findings revealed that the isolates SD3, SD2, KD1, KD5, UK1, and UK3 reduced the deleterious effects of UVB radiation on mung bean plants and can be used to protect seedlings from UVB radiation for sustainable agriculture. [ABSTRACT FROM AUTHOR]

Maqui berry (Aristotelia chilensis) is characterized by antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the effect of maqui berry extracts on human skin fibroblasts (NHSFs) exposed to ultraviolet radiation (UVB). The photoprotective properties of the extracts were investigated via the determination of the total polyphenolic content (TPC) and antioxidant capacity (DPPH), and the chemical composition was assessed. The chemical purity of the extracts was studied via the evaluation of the toxic elements level. The water extract (MWE 57.75 ± 0.44 mg GAE/g) had the highest mean polyphenol content. The water (MWE) and ethanol (MEE70) extracts had the highest inhibitory activities against DPPH radical formation (283.63 ± 7.29 and 284.60 ± 4.31 mg Tx/L, respectively). The analyzed extracts were found to be safe in terms of toxic elements (arsenic, cadmium, lead). The tested extracts of maqui berry did not cause a cytotoxic effect on NHSF cells after 24, 48, and 72 h of incubation. When the NHSF cells were exposed to UVB radiation in the presence of maqui extracts, their viability was increased or maintained. The maqui berry extracts had a slightly protective effect against skin damage caused by UVB radiation. These were preliminary studies that require further research to determine which maqui compounds correspond with the photoprotective activity. [ABSTRACT FROM AUTHOR]

It is known that UVB radiation induces several adverse skin alterations starting from simple photoaging to skin cancer. In addition, it was demonstrated that reactive oxygen species (ROS) were found to be related to cancer development and progression. The aim of study was to examine whether male hairless (SKH-1) mice (Mus musculus) that were subchronically exposed to UVB radiation presented with actinic keratosis (AK) and squamous cell carcinoma lesions, and that treatment with latex C-serum cream significantly prevented abnormal skin development. Data demonstrated for the first time the photoprotective activity of latex C-serum extracted from the rubber tree Hevea brasiliensis var. subconcolor Ducke. Latex C-serum prevented the progression of AK to squamous cell carcinoma in SKH-1 mice, indicating that mice topically treated with latex C-serum presented only AK lesions and treatment with the highest concentration (10%) significantly reduced epidermal thickness, suggesting diminished cell proliferation. Latex C-serum protected the skin of mice against oxidative stress damage, increasing catalase (CAT) activity, regenerating glutathione (GSH) levels, lowering thiobarbituric acid-reactive species (TBARS) production and regenerating the total antioxidant capacity (TAC) of the skin. Evidence that UV radiation in skin induced systemic alterations and erythrocytic analysis indicated that latex C-serum increased CAT activity and GSH levels. Taken together these data indicate that latex C-serum plays an important antioxidant and photoprotective role, preventing serious damage to the skin following exposure to UVB radiation. [ABSTRACT FROM AUTHOR]

Background: Although chlorpyrifos (CPS) has been banned in many developed countries, it still remains one of the best-selling pesticides in the world. Widespread environmental and occupational exposure to CPS pose a serious risk to human health. Another environmental factor that can adversely affect human health is ultraviolet radiation B (UVB, 280–315 nm wave length). Here we attempt determine if exposure to CPS can modify toxic effects of UVB. Such situation might be a common phenomenon in agriculture workers, where exposure to both factors takes place. Methods: Two skin cell lines; namely human immortalized keratinocytes HaCaT and BJ human fibroblasts were used in this study. Cytotoxicity was investigated using a cell membrane damage detection assay (LDH Cytotoxicity Assay), a DNA damage detection assay (Comet Assay), an apoptosis induction detection assay (Apo-ONE Homogeneous Caspase-3/7 Assay) and a cell reactive oxygen species detection assay (ROS-Glo H2O2 assay). Cytokine IL-6 production was also measured in cells using an ELISA IL-6 Assay. Results: Pre-incubation of skin cells with CPS significantly increased UVB-induced toxicity at the highest UVB doses (15 and 20 mJ/cm2). Also pre-exposure of BJ cells to CPS significantly increased the level of DNA damage, except for 20 mJ/cm2 UVB. In contrast, pre-exposure of HaCaT cells, to CPS prior to UVB radiation did not cause any significant changes. A decrease in caspase 3/7 activity was observed in HaCaT cells pre-exposed to 250 µM CPS and 5 mJ/cm2 UVB. Meanwhile, no statistically significant changes were observed in fibroblasts. In HaCaT cells, pre-exposure to CPS resulted in a statistically significant increase in ROS production. Also, in BJ cells, similar results were obtained except for 20 mJ/cm2. Interestingly, CPS seems to inhibited IL-6 production in HaCaT and BJ cells exposed to UVB (in the case of HaCaT cells for all UVB doses, while for BJ cells only at 15 and 20 mJ/cm2). Conclusions: In conclusion, the present study indicates that CPS may contribute to the increased UVB-induced toxicity in skin cells, which was likely due to the induction of ROS formation along with the generation of DNA damage. However, further studies are required to gain better understanding of the mechanisms involved. [ABSTRACT FROM AUTHOR]

Solar ultraviolet B (UVB) radiation is a major skin cancer-causing agent. Initiation, promotion, and progression are the diverse phases of UVB-induced carcinogenesis. Exposure to UVB causes abnormalities in a series of biochemical and molecular pathways: thymine dimer formation, DNA damage, oxidative stress, inflammatory responses, and altered cell signaling, eventually resulting in tumor formation. The increased skin cancer rates urge researchers to develop more efficient drugs, but synthetic chemotherapeutic drugs have more contrary effects and drug resistance issues, which have been reported recently. The current review focuses on the relationship between microbes and cancer. Human skin acts as a barrier against the external environment and serves as a protective shield for its inhabitant microbiota, collectively called skin microbes. The gut microbiome plays a vital role in cancer therapy. Production of short-chain fatty acids (SCFAs) such as butyrate, acetate, and propionate by intestinal microbes has anti-cancer properties against various cancer cell lines. Yet, the knowledge of SCFAs produced by skin microbes remains yet to be elucidated exhaustively. In this review, we strive to summarize the findings of studies performed to date regarding the anti-cancer properties of SCFA against various cancer cell lines and provide insight into future directions in the skin microbiome field. [ABSTRACT FROM AUTHOR]

Long-term field studies of the effect of presowing seed treatment of spring wheat (Triticum aestivum L.) with XeCl-excilamp UVB radiation on sowing qualities of seeds and plant productivity have been carried out. The features of morphogenesis at various stages of growth and development of wheat plants have been determined. A subdose of exposure has been identified that increases the crop yield. The studies prove the prospects of introducing UVB treatment into the pool of modern agricultural technologies. [ABSTRACT FROM AUTHOR]

Ultraviolet type B (UVB) radiation plays an important role in hyperpigmentation disorder, which induces cellular oxidative stress and causes abnormal melanin production and secretion. The stress condition plays an essential role in actin polymerization relating to F-actin rearrangement and forms dendrite to send melanin pigment to the uppermost layer of the skin. Phenolic compounds are secondary metabolites that mainly synthesize under stress conditions to protect plants from harmful environments and have been reported as effective agents in anti-oxidant and anti-melanogenesis. However, the influence of phenolic compounds on F-actin rearrangement-associated dendrite formation has not been studied so far. Hence, this study aimed to investigate the enhancing phytophenolic targets in riceberry rice (Oryza sativa L.) germination and UVB radiation (RR-GR) to suppress melanogenesis relating to F-rearrangement. As a result, the RR-GR had the potential to enhance phenolic acids such as protocatechuic and vanillic acid, which have been proven to possess anti-oxidant activity and anti-tyrosinase properties. Riceberry rice's modification showed the potential to reduce cellular oxidative stress and suppress B16F10 melanogenesis relating to F-actin rearrangement that is associated with dendrite formation. [ABSTRACT FROM AUTHOR]

The aim of this research is to investigate the sterilizing effect of UVB radiation on the degradation and oxidation of low- and high-density polyethylene specimens using ASTM 638 and 695. Polyethylene is a reliable, efficient, and low-cost biomaterial and an alternative to various bone transplants. Twenty high-density polyethylene (HDPE) specimens and twenty low-density polyethylene (LDPE) specimens were used for tensile and compression testing. The dosage of 13.5 J/cm2 was chosen with an exposure time of 48 minutes during the sterilization process. In terms of mechanical tensile properties, LDPE has a lower effect compared with HDPE. The p-value of yield stress equals 3.008×10−4, the p-value of ultimate stress equals 2.5×10−4, and the p-value of break stress equals 0.0075. [ABSTRACT FROM AUTHOR]

An analysis of data on the density of annual rings of conifers for the periods 1979‒1993 and 1979‒2006 allows us to identify patterns in the response of trees, taking into account the processes of abnormal decrease and natural recovery of total ozone content (TOC). Reconstructions of changes in TOC over the past 300 years along the Ural meridian according to the TEMIS (Tropospheric Emission Monitoring Internet Service project) satellite monitoring of TOC and stem wood responses observed in data on the maximum density of annual rings of pine, spruce, and larch have been performed on the basis of methods of dendrochronological and spectral singular analysis, which made it possible to compare the current and past state of stratospheric ozone fields. Although changes in stratospheric ozone can play the role of a factor significantly limiting the annual growth of wood, such an approach to estimates works only under conditions of overlapping responses of trees under UVB effects in the spectral range of 280‒315 nm on stress responses from other climatic factors. Based on the results of a numerical modeling for three latitude ranges, models of maximum annual density are calculated in terms of changes in TOC and reconstructions of their past changes are given. The aridity of the climate and its cyclicity increase the stress effect of the ozonosphere on vegetation associated with an increase in UVB radiation and allow us to differentiate the responses of trees according to stressors by statistical methods. Reconstructions of TOC from April to September for the Ural meridian show that the level of TOC has not yet reached previous historical values. [ABSTRACT FROM AUTHOR]

Background: Ultraviolet (UV) radiation‐induced oxidative stress is the main cause of photodamage to the skin. Glutathione (GSH) serves important physiological functions, including scavenging oxygen‐free radicals and maintaining intracellular redox balance. γ‐glutamylcysteine (γ‐GC), as an immediate precursor of GSH and harboring antioxidant and anti‐inflammatory properties, represents an unexplored option for skin photodamage treatment. Purpose: The purpose of this study was to investigate whether γ‐GC can reduce UVB‐induced NIH‐3T3 cell damage. Methods: The experimental groups were as follows: control, UVB radiation, UVB radiation after pretreatment with γ‐GC. Cell counting kit‐8 (CCK‐8) assays were used to measure cell proliferation, flow cytometry, and immunoblotting to detect the apoptosis rate and apoptosis‐associated proteins. The levels of Reactive Oxygen Species (ROS), Superoxide Dismutase (SOD), and GSH/GSSG (oxidized GSH) were measured to assess oxidative stress. Immunoblotting and immunofluorescence were used to detect DNA damage. The members of the MAPK signaling pathways were detected by immunoblotting. Results: UVB irradiation significantly reduced cell viability and destroyed the oxidative defense system. Pretreatment with γ‐GC reduced UVB‐induced cytotoxicity, restored the oxidation defense system, and inhibited activation of the MAPK pathway. It also reduced the apoptosis rate, downregulated the levels of cleaved caspase 3 and cleaved PARP. Furthermore, pretreatment with γ‐GC reduced the accumulation of γH2AX after UVB radiation exposure, indicating that γ‐GC could protect cells from DNA damage. Conclusion: γ‐GC protected NIH‐3T3 from damage caused by UVB irradiation. The photoprotective effect of γ‐GC is mediated via strengthening the endogenous antioxidant defense system, which prevents DNA damage and inhibits the activation of the MAPK pathway. [ABSTRACT FROM AUTHOR]

Sweet pepper fruits (Capsicum annuum L.) contain various nutrients and phytochemicals that enhance human health and prevent the pathogenesis of certain diseases. Here, we report that oral administration of orange sweet pepper juices prepared by a high-speed blender and low-speed masticating juicer reduces UVB-induced skin damage in SKH-1 hairless mice. Sweet pepper juices reduced UVB-induced skin photoaging by the regulation of genes involved in dermal matrix production and maintenance such as collagen type I α 1 and matrix metalloproteinase-2, 3, 9. Administration of sweet pepper juices also restored total collagen levels in UVB-exposed mice. In addition, sweet pepper juices downregulated the expression of pro-inflammatory proteins such as cyclooxygenase-2, interleukin (IL)-1β, IL-17, and IL-23, which was likely via inhibiting the NF-κB pathway. Moreover, primary antioxidant enzymes in the skin were enhanced by oral supplementation of sweet pepper juices, as evidenced by increased expression of catalase, glutathione peroxidase, and superoxide dismutase-2. Immunohistochemical staining showed that sweet pepper juices reduced UVB-induced DNA damage by preventing 8-OHdG formation. These results suggest that sweet pepper juices may offer a protective effect against photoaging by inhibiting the breakdown of dermal matrix, inflammatory response, and DNA damage as well as enhancing antioxidant defense, which leads to an overall reduction in skin damage. [ABSTRACT FROM AUTHOR]

Anthopleura hermaphroditica is an intertidal anemone that lives semi-buried in soft sediments of estuaries and releases its brooded embryos directly to the benthos, being exposed to potentially detrimental ultraviolet radiation (UVR) levels. In this study, we investigated how experimental radiation (PAR: photosynthetically active radiation; UVA: ultraviolet A radiation; and UVB: ultraviolet B radiation) influences burrowing (time, depth and speed) in adults and juveniles when they were exposed to PAR (P, 400–700 nm), PAR + UVA (PA, 315–700 nm) and PAR + UVA + UVB (PAB, 280–700 nm) experimental treatments. The role of sediment as a physical shield was also assessed by exposing anemones to these radiation treatments with and without sediment, after which lipid peroxidation, protein carbonyls and total antioxidant capacity were quantified. Our results indicate that PAB can induce a faster burial response compared to those anemones exposed only to P. PAB increased oxidative damage, especially in juveniles where oxidative damage levels were several times higher than in adults. Sediment offers protection to adults against P, PA and PAB, as significant differences in their total antioxidant capacity were observed compared to those anemones without sediment. Conversely, the presence or absence of sediment did not influence total antioxidant capacity in juveniles, which may reflect that those anemones have sufficient antioxidant defenses to minimize photooxidative damage due to their reduced tolerance to experimental radiation. Burrowing behavior is a key survival skill for juveniles after they have been released after brooding. [ABSTRACT FROM AUTHOR]

Simple Summary: Non-melanoma skin cancer (NMSC) is the main type of cancer in the Caucasian population, and the number of cases continues to rise. Research mostly focuses on clinical characteristics analysis, but genetic features are crucial to malignancies' establishment and advance. We aim to explore the genetic basics of skin cancer, surrounding microenvironment interactions, and regulation mechanisms to provide a broader perspective for new therapies' development. Skin cancer is one of the main types of cancer worldwide, and non-melanoma skin cancer (NMSC) is the most frequent within this group. Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common types. Multifactorial features are well-known for cancer development, and new hallmarks are gaining relevance. Genetics and epigenetic regulation play an essential role in cancer susceptibility and progression, as well as the variety of cells and molecules that interact in the tumor microenvironment. In this review, we provide an update on the genetic features of NMSC, candidate genes, and new therapies, considering diverse perspectives of skin carcinogenesis. The global health situation and the pandemic have been challenging for health care systems, especially in the diagnosis and treatment of patients with cancer. We provide innovative approaches to overcome the difficulties in the current clinical dynamics. [ABSTRACT FROM AUTHOR]

Human skin is the largest organ and the most external interface between the environment and the body. Vast communities of viruses, bacteria, archaea, fungi, and mites, collectively named the skin microbiome (SM), cover the skin surface and connected structures. Skin-resident microorganisms contribute to the establishment of cutaneous homeostasis and can modulate host inflammatory responses. Imbalances in the SM structure and function (dysbiosis) are associated with several skin conditions. Therefore, novel target for the skincare field could be represented by strategies, which restore or preserve the SM natural/individual balance. Several of the beneficial effects exerted by the SM are aroused by the microbial metabolite butyrate. Since butyrate exerts a pivotal role in preserving skin health, it could be used as a postbiotic strategy for preventing or treating skin diseases. Herein, we describe and share perspectives of the potential clinical applications of therapeutic strategies using the postbiotic butyrate against human skin diseases. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the ameliorative effect of curcumin and ascorbic acid against ultraviolet (UVB)-induced thyroid toxicity and to study the haemtological and biochemical parameters. Twenty-four female Wistar rats, aged 3-4 months and weighing 130-150 g, were used, and the rats were divided into four Groups (Groups I to IV). Group I received standard food and water ad libitum and was treated as a control; Group II received a dose of 280 nm of UVB radiation for 2 hrs/day. Group III received 280 nm UVB radiation for 2 hrs/day and received curcumin 25 mg/kg body weight given orally. Group IV received 280 nm of UVB radiation for 2 hrs/day and received ascorbic acid 250 mg/kg body weight given orally. All the treatments were consequently performed for 15 days. The results showed that haemtological parameters such as haemoglobin (Hb) (p<0.05), red blood cells (RBCs), white blood cells (WBCs), MCV, MCH, and MCHC decreased significantly. Biochemical parameters included lipid peroxidation (LPO) (p<0.05), H2O2 (p<0.01), nitric oxide (NO), superoxide dismutase (SOD) (p< 0.01), catalase (p<0.01), glutathione-S-transferase (GST) (p<0.01), and glutathione reductase. NO increased, and glutathione (GSH) (p<0.01) decreased significantly. However, cotreatment with curcumin and ascorbic acid significantly increased the haemtological parameters. In addition, oxidative parameters such as LPO (p<0.01), SOD (p< 0.01), CAT (p<0.01), GST (p<0.01), and NO (p<0.01) significantly increased, and GSH (p<0.01) significantly decreased upon cotreatment with curcumin and ascorbic acid. The results indicated the ameliorative effect of curcumin and ascorbic acid against UVB-induced thyroid toxicity in female Wistar rats. [ABSTRACT FROM AUTHOR]

Amphibians are declining around the world as they are particularly sensitive to multiple environmental stressors, among them the increase of UVB radiation and the environmental contaminations of body waters caused by agrochemicals. Because of the limited research on the interaction between agrochemicals and UVB radiation on tropical amphibians, we performed this study to test the hypothesis that the exposure to UVB radiation will enhance the toxic effects of the organophosphorus (OPs) insecticides chlorpyrifos, diazinon and monocrotophos, which are widely used in Colombia, on tadpoles from three tropical anuran species. Under laboratory conditions, we exposed independently tadpoles of Boana xerophylla, Engystomops pustulosus and Rhinella horribilis to each of the three insecticides with the presence of UVB radiation and without UVB, during 96 h toxicity tests. We then examined their effects on tadpole mortality, capacity to swim and total length. We found that UVB enhanced the mortality of insecticides (these treatments had a lower LC50 than those without UVB radiation), increased the tadpole immobility (they were unable to swim), and decreased the total length. Therefore, we validated the prediction that UVB radiation enhances the toxicity of the OPs insecticides studied on our anuran species and consequently may be one of the causal factors of amphibian population declines in the tropical countries. However, we suggest to perform more realistic field studies in areas with agrochemical presence to a better understanding of the effect of these stressors on anurans as there are environmental factors that attenuate underwater UVB radiation and toxicity in aquatic organisms, although it is also known that under field conditions some OPs insecticides become more toxic in the presence of UVB. [ABSTRACT FROM AUTHOR]

Data on the effect of global warming on the ozone layer and the intensity of near-surface near-noon UVB radiation in 2100 compared to the year 2000 are presented. Changes in the ozone layer are calculated at a latitude of 50° N for January and June of 2100 when compared with 2000 using the one-dimensional photochemical model, as well as the SOCRATES interactive two-dimensional photochemical model, using greenhouse gas concentrations given in the scenarios of the Intergovernmental Panel on Climate Change (IPCC) RCP 4.5 and PCP 6.0. Surface UVB radiation fluxes for the above conditions are calculated using a program developed at the Norwegian Institute for Atmospheric Research in 2005 (by Ola Engelsen). [ABSTRACT FROM AUTHOR]

Introduction: The effect of fullerene nanoemulsion on skin wrinkle repair in an animal model was evaluated using ultrasonic images processing. Methods: Wrinkles were created in C57BL6 mice during 35 days of UVB radiation. Then, to investigate the therapeutic effect of fullerene nanoemulsions, mice were divided into three groups of control, UVB radiation, and treatment with fullerene nanoemulsion. Stable fullerene nanoemulsions were prepared using shear equalization. The therapeutic effect of fullerene nanoemulsion was investigated by extracting the skin thickness and mechanical parameters. Histology studies were performed to confirm the reliability of the treatment. Results: A significant decrease was observed in the thickness of the epidermis and dermis layers (43% and 36%), Young modulus (27%), and the shear modulus (20%) of the skin on day 28 of the fullerene nanoemulsion treatment. Skin stiffness obtained by tensiometry on day 28 of the treatment showed a 48% reduction in the treatment group compared with the control group. Histological results confirmed the effect of fullerene nanoemulsions on wrinkle repair. Conclusion: The healing effect of fullerene nanoemulsion in wrinkle repair was confirmed. To study the skin repair, parameters including Young modulus, the shear modulus, and skin layer thickness can be calculated using ultrasonic images processing. [ABSTRACT FROM AUTHOR]

Objectives: At the end of a 60‐day course of narrowband UVB phototherapy, administered to individuals with early multiple sclerosis, there were changes in the relative proportions of circulating B‐cell subsets. This study investigated phototherapy‐associated changes to cytokine responses of B cells when exposed to a TLR7 ligand. Methods: PBMCs from participants of the PhoCIS (Phototherapy for Clinically Isolated Syndrome) trial taken before (day 1) and after phototherapy for 8 weeks (day 60) were incubated with, or without, the TLR7 ligand, R848, for 18 h. Production of TNF and IL‐10 in seven B‐cell subsets was examined, with cytokine responses in each individual at day 60, adjusted for responses at day 1. Paired PBMCs were from participants administered phototherapy (n = 7) or controls (n = 6). Results: At day 60, significantly fewer B cells, particularly marginal zone‐like B cells (CD27+/IgD+), from participants administered phototherapy produced TNF in response to TLR7 stimulation. When responses by seven B‐cell subsets were analysed together using multivariate methods, a phototherapy‐specific signature was observed. An increased responsiveness from day 1 to day 60 in IgM‐only memory B cells (CD27+/IgD−/IgM+) after TLR7 stimulation also predicted slower progression from CIS to MS. Phototherapy was without significant effect on B‐cell IL‐10 production. Conclusions: Reduced TNF responses after TLR7 stimulation in marginal zone‐like B cells from participants administered phototherapy suggested treatment‐associated priming effects that were detected upon subsequent polyclonal B‐cell activation. Changes in responsiveness to TLR7 stimulation also suggested that IgM‐only memory B cells may be important in conversion from CIS to MS. [ABSTRACT FROM AUTHOR]

Background: ultraviolet radiation types A and B (UV) (400–315nm and 315–280nm respectively) are the main components present in sunlight known to cause skin injuries. Arnica montana is a plant that has been widely studied for containing anti-inflammatory, healing and analgesic properties capable of preventing or ameliorating lesions. Here, we investigated the therapeutic effect of topical application of Arnica montana after UVB-induced cutaneous injuries in mice. Methods: mice were exposed to UVB radiation (Philips TL40W/12 RS lamp) in a period of 3 hours. After one hour of radiation exposure, the animals were treated with topical application of Arnica montana ointment (250 mg/g) in the ear. At the time of 16 hours after treatment, the parameters of edema, oxidative stress and inflammatory reaction were measured in the ear of mice. Results: our results demonstrated that topical treatment with Arnica montana reduced the UVB-induced inflammatory response as demonstrated by the reduction of ear edema, inhibition of myeloperoxidase activation, decrease of nuclear factor kappa B levels and reduction of proinflammatory cytokines levels, such as interleukin-1beta, interleukin-6, tumour necrosis factor-alpha and interferon-gamma. In addition, Arnica montana ameliorated oxidative damage mediated by UVB radiation, as demonstrated by the reduction of lipid peroxidation, protein oxidation and increase of tissue antioxidant capacity and glutathione levels in the ear. Conclusion: we concluded that Arnica montana ointment is effective in alleviating the auricular inflammatory process and oxidative damage induced by acute UVB radiation, sustaining the traditional use of Arnica montana for the treatment of skin disorders. [ABSTRACT FROM AUTHOR]

Skin protection against ultraviolet (UV) radiation is necessary to reduce sunburn damage (erythema) and has been recognized as an important preventive measure against the development of cancer. Many sun-blocking pharmaceutical products are based on titanium dioxide nanomaterials (TiO2 NMs) due to their UV barrier properties. This study aimed to assess if the UV protective efficiency of TiO2 NMs depends on their shape. We prepared TiO2 nanowires (TNW), TiO2 nanotubes (TNT), and TiO2 nanoplates (TNP) and tested their effects on human keratinocytes before and after UVB irradiation under in vitro exposure settings. The UVB radiation was applied at the dose equivalent to the UV component observed in one medial erythemal dose. The biological effects of TiO2 NMs on nonirradiated and UVB-irradiated keratinocytes were observed by means of cell viability, genotoxicity, and inflammatory response. The obtained results clearly showed that the effects of TiO2 NMs in vitro, either cytotoxic or protective, depend on their shape. These observations highlight the beneficial properties of nanomaterials that can improve the quality and efficacy of nano-enabled products only if the safe-by-design concept has been implemented during the innovation process. [ABSTRACT FROM AUTHOR]

Ultraviolet-B (UVB) irradiation causes imbalance between dermal matrix synthesis and degradation through aberrant upregulation of matrix metalloproteinases (MMPs), which leads to overall skin photoaging. We investigated the effects of extracellular vesicles (EVs) derived from human adipose-derived stem cells (HASCs) on photo-damaged human dermal fibroblasts (HDFs). EVs were isolated from conditioned media of HASCs with tangential flow filtration and characterized using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), western blotting, micro RNA (miRNA) arrays, cytokine arrays and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The effects of EVs on the UVB-irradiated HDFs were evaluated using scratch assay, ELISA and real-time PCR. Microarrays exhibited that EVs are rich in various miRNAs and proteins, and that these EV contents are linked to a broad range of biological functions, including fibroblast proliferation, UV protection, collagen biosynthesis, DNA repair and cell ageing. A scratch assay showed that HASC-EVs enhanced the migration ability of UVB-irradiated HDFs. Real-time RT-PCR and ELISA analyses revealed that the HASC-derived EVs significantly suppressed the overexpression of MMP-1, -2, -3 and -9 induced by UVB irradiation and enhanced the expression of collagen types I, II, III and V and elastin. In particular, tissue inhibitor of metalloproteinase (TIMP)-1 and transforming growth factor (TGF)-β1, which are important factors involved in MMP suppression and ECM synthesis, were upregulated in EV-treated HDFs after UVB irradiation. Overall results suggest that diverse components that are enriched in HASC-derived EVs could act as a biochemical cue for recovery from skin photoaging. [ABSTRACT FROM AUTHOR]

A UV exclusion experiment was conducted on durum wheat (Triticum durum Desf. var. Claudio) grown in pots. Plants were grown under three different radiative treatments in greenhouses covered with plastic filters: Teflon, transparent to the entire region of natural UV‐visible sunlight (TEF); polyester, transparent above 312 nm (MYL, excluding UVB) and Lee, transparent above 400 nm (LEE, excluding both UVA and UVB). Analyses have been carried out to determine the concentration of photosynthetic pigments in leaves, UV‐absorbing compounds, nitrogen and carbon in leaves, culms and spikes and proteins and gluten in grains. In particular, plants grown under UV exclusion showed a reduction in protein and dry gluten content (consequently without variation in the ratio dry gluten/protein), but at the same time, a significant increase of gluten index, which is a parameter to define the quality of gluten, was observed. The results highlighted the influence played by UV radiation on some biochemical parameters, mainly UV‐absorbing compounds, leaf nitrogen and grain protein characteristics of durum wheat cultivated under Mediterranean conditions. In particular, natural level of UV in the Mediterranean improves the characteristics of durum wheat flour important for pasta production (high dry gluten level), while the UV exclusion could improve characteristics of flour important for bread production (high gluten index). [ABSTRACT FROM AUTHOR]

Daphniopsis tibetana Sars lives in elevation, usually with strong solar UV radiation. We speculate that UV may have an effect on the ecology and evolutionary biology of this species. However, the regulatory effect and mechanism of UV on D. tibetana have not been studied previously. Here, our results showed that UVB could act as a positive factor in the relative body lengths, reproductive parameters, and population growth parameters of D. tibetana when UVB radiation is 20–170 mJ cm−2, compared with the control group. Strikingly, these parameters were highest at 120 mJ cm−2. To explore the mechanism underlying the UVB irradiation effects, we conducted a transcriptome analysis using the Trinity platform. The results indicated that differentially regulated genes were mostly enriched in lipid transport and lipid localization by Gene Ontology (GO) enrichment analysis of 146 differentially expressed genes (83 upregulated and 63 downregulated). This is the first study of UVB radiation of D. tibetana to reveal genes that may have crucial roles in survival, growth, and reproduction and could be candidates for future functional studies. Additionally, the study could supply a substantial resource for investigating and elucidating lipids that could play important roles in a physiological context. [ABSTRACT FROM AUTHOR]

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Prickly pear (Opuntia ficus-indica cv. Rojo Vigor) fruit is an excellent source of secondary metabolites with health-promoting properties (i.e., betalains, flavonoids, and ascorbic acid), and thus, it is relevant to find postharvest treatments that increase their concentration. Postharvest abiotic stresses such as wounding and ultraviolet radiation can induce the accumulation of secondary metabolites in different horticultural crops. In the present study, the effect of ultraviolet B (UVB) radiation applied alone or combined with wounding stress on the accumulation of betalains, phenolics, and ascorbic acid in red prickly pear was evaluated. Whole and wounded fruit samples were treated with UVB radiation (6.4 W m−2) for 0, 15, 90, and 180 min and stored for 24 h at 16 °C. The content of bioactive compounds was evaluated before and after storage. The application of UVB radiation for 15 min was the most adequate treatment to induce the accumulation of bioactive compounds. In this context, UVB radiation (15 min) of the wounded tissue resulted on an immediate accumulation of betalains (33-40%) and ascorbic acid (54-58%) in the pulp and peel of the fruit. Likewise, after storage, the pulp of irradiated whole fruits showed the highest accumulation of phenolics (125.8%) and betalains (49.8%) as compared with the control, whereas the stored wounded tissue treated with UVB presented accumulation of ascorbic acid in the pulp (67.2%) and peel (84.6%). The stressed tissue with enhanced concentration of nutraceuticals could be transformed into functional processed foods or used as raw material for the extraction of compounds with applications in health-related markets. [ABSTRACT FROM AUTHOR]

UVB radiation (290-320 nm) causes diverse effects in plant cells that vary with the fluence rate of exposure. High fluence rates of UVB radiation cause damage to DNA and formation of reactive oxygen species in mitochondria and chloroplasts, which lead to oxidation of membrane proteins and lipids and inhibition of cellular functions. In response to oxidative stress, mitochondrial transmembrane potential dissipates, resulting in cytochrome c release and activation of metacaspases. This leads to the apoptosis-like cell death. The signaling mechanism based on UVB DNA damage includes check-point activation, cell-cycle arrest, and finally programmed cell death with characteristic DNA fragmentation and morphological hallmarks typical of apoptotic cells. Recently, it was shown that among the components of this signaling mechanism the transcriptional factor SOG1 (suppressor of gamma response 1) plays a key role in regulation of programmed cell death in plants. In contrast to its damaging effects, UVB radiation at low fluence rates can act as a regulatory signal that is specifically perceived by plants to promote acclimation and survival in sunlight. The protective action of UVB is based on expression of various genes, including those encoding flavonoid synthesis enzymes that provide a UVB-absorbing sunscreen in epidermal tissues and DNA photorepair enzymes. These processes are mediated by the UVB photoreceptor UVR8, which has been recently characterized at the molecular level. Now progress is made in uncovering the UVR8-mediated signaling path-way mechanism in the context of UVB photon perception and revealing the biochemical components of the early stages of light signal transduction. In this review, attention is focused on the achievements in studying these UVB-induced signaling processes. [ABSTRACT FROM AUTHOR]

Caulerpa sp., a genus of seaweed native to the Indo-Pacific region, has been known for its antioxidant properties and health benefits when consumed as food. Previous studies have reported Caulerpa sp.'s potential as a strong antioxidant, but its effects on the skin in a topical preparation, especially its role in UV protection, have not been studied extensively. Our study investigated the protective effects of 0.2% and 0.4% Caulerpa sp. extract gels on photoaging in the UVB-irradiated skin of Wistar mice. The subjects were divided into naive control, vehicle control, and 3 treatment groups (0.2% Caulerpa sp. extract gel, 0.4% Caulerpa sp. extract gel, and 0.02% astaxanthin gel as a standard antioxidant). The groups, except the naive control group, received a total of 840 mJ/cm2 of UVB irradiation in four weeks. Protective effects of the extract were measured through the evaluation of collagen expression, MMP-1 expression and levels, and 8-OhDG expression. Mice who received topical application of Caulerpa sp. extract gel had higher collagen expression, betterpreserved collagen structure, lower levels of MMP-1, and less MMP-1 and 8-OHdG expressions compared to the vehicle control group. There was no difference between different concentrations of the extract. Our findings demonstrated that topical application of Caulerpa sp. extract gel significantly protected UVB-irradiated mice skin from photoaging. [ABSTRACT FROM AUTHOR]

Annually, more skin cancer cases are diagnosed than the collective incidence of the colon, lung, breast, and prostate cancer. Persistent contact with sunlight is a primary cause for all the skin malignancies. UVB radiation induces reactive oxygen species ( ROS) production in the skin which eventually leads to DNA damage and mutation. Various delivery approaches for the skin cancer treatment/prevention have been evolving and are directed toward improvements in terms of delivery modes, therapeutic agents, and site-specificity of therapeutics delivery. The effective chemoprevention activity achieved is based on the efficiency of the delivery system used and the amount of the therapeutic molecule deposited in the skin. In this article, we have discussed different studies performed specifically for the chemoprevention of UVB-induced skin cancer. Ultra-flexible nanocarriers, transethosomes nanocarriers, silica nanoparticles, silver nanoparticles, nanocapsule suspensions, microemulsion, nanoemulsion, and polymeric nanoparticles which have been used so far to deliver the desired drug molecule for preventing the UVB-induced skin cancer. [ABSTRACT FROM AUTHOR]

Ginsenoside Rc (Rc) is a major ginsenoside isolated from Panax ginseng, and has exhibited pharmacological effects on skin cells. The present study aimed to investigate the putative skin‑protective properties of Rc, including its anti‑photoaging and barrier function‑protective effects, in human HaCaT keratinocytes exposed to UVB radiation. The protective properties of Rc were evaluated through the assessment of keratinocyte viability, reactive oxygen species (ROS) production, total glutathione (GSH) and superoxide dismutase (SOD) activity, caspase‑14, matrix metalloproteinase (MMP)‑2 and ‑9 activity, and MMP‑2, MMP‑9 and filament aggregating protein (filaggrin) expression following UVB irradiation. Treatment with Rc was revealed to prevent the UVB‑induced increase in ROS production and pro‑MMP‑2 and ‑9 levels in HaCaT keratinocytes. In addition, treatment with Rc resulted in enriched GSH contents and enhanced SOD activity following exposure to UVB radiation. Furthermore, Rc treatment enhanced caspase‑14 activity and counteracted the UVB‑induced downregulation in filaggrin expression. However, no significant difference was identified between Rc‑treated and normal groups in terms of keratinocyte viability, regardless of exposure to radiation. The present findings suggested that Rc may exert anti‑photoaging and barrier function‑protective effects in keratinocytes, and thus protect the skin against photooxidative stress induced by exposure to UV radiation. [ABSTRACT FROM AUTHOR]

The human body through its largest organ, the skin, is undoubtedly subject to the invasive action of multiple environmental factors. one of the most aggressive factors is ultraviolet radiation which can lead to immunosuppression, decreasing the body's capacity to fight infection and also cancer. In this study, was investigated the influence of ultraviolet B-type radiation on skin cells, keratinocytes and fibroblasts, by in vitro and in vivo assays. Regarding in vitro tests, viability of two cell type, verified by the means of Trypan and Alamar blue assays showed a significant affectation by a dose of radiation of 60 mJ/cm². Moreover, in vivo study confirm the aggressive nature of this type of radiation, skin physiological parameters being visibly affected, in terms of an increase in erythema and transepidermal water loss values and a decrease in skin hydration values. The histopathological analysis support the data obtained and showed the apparition of pre-malignant lesions in group of mice exposed to UVB. [ABSTRACT FROM AUTHOR]

Deschampsia antarctica Desv. is one of two vascular plants that live in the Maritime Antarctic Territory and is exposed to high levels of ultraviolet-B (UVB) radiation. In this work, antioxidant physiology of D. antarctica was studied in response to UVB induced oxidative changes. Samples were collected from Antarctica and maintained in vitro culture during 2 years. Plants were sub-cultured in a hydroponic system and exposed to 21.4 kJ m-2 day-1, emulating summer Antarctic conditions. Results showed rapid and significant increases in reactive oxygen species (ROS) at 3 h, which rapidly decreased. No dramatic changes were observed in photosynthetic efficiency, chlorophyll content, and level of thiobarbituric acid reactive species (MDA). The enzymatic (superoxide dismutase, SOD and total peroxidases, POD) and non-enzymatic antioxidant activity (total phenolic) increased significantly in response to UVB treatment. These findings suggest that tolerance of D. antarctica to UVB radiation could be attributed to its ability to activate both enzymatic and non-enzymatic antioxidant systems. [ABSTRACT FROM AUTHOR]

Plants recruit microbial communities from the soil in which they germinate. Our understanding of the recruitment process and the factors affecting it is still limited for most microbial taxa. We analysed several factors potentially affecting root microbiome structure – the importance of geographic location of natural populations, the microbiome of native seeds as putative source of colonization and the effect of a plant's response to UVB exposure on root colonization of highly abundant species. The microbiome of Nicotiana attenuata seeds was determined by a culture-dependent and culture-independent approach, and the root microbiome of natural N. attenuata populations from five different locations was analysed using 454-pyrosequencing. To specifically address the influence of UVB light on root colonization by Deinococcus, a genus abundant and consistently present in N. attenuata roots, transgenic lines impaired in UVB perception (irUVR8) and response (irCHAL) were investigated in a microcosm experiment with/without UVB supplementation using a synthetic bacterial community. The seed microbiome analysis indicated that N. attenuata seeds are sterile. Alpha and beta diversities of native root bacterial communities differed significantly between soil and root, while location had only a significant effect on the fungal but not the bacterial root communities. With UVB supplementation, root colonization of Deinococcus increased in wild type, but decreased in irUVR8 and irCHAL plants compared to nontreated plants. Our results suggest that N. attenuata recruits a core root microbiome exclusively from soil, with fungal root colonization being less selective than bacterial colonization. Root colonization by Deinococcus depends on the plant's response to UVB. [ABSTRACT FROM AUTHOR]

Aim Stratospheric ozone depletion and simultaneous increases in UVB radiation due to human activities have the potential to affect freshwater biota. The goal of our study is to summarize the impacts of UVB on freshwater biota by comparing the differences in the general patterns, including the directions and the magnitudes of the impacts of UVB on four major freshwater taxa (phytoplankton, zooplankton, fish and amphibians). The potential driving forces for these differences are also explored. Location Global. Methods We performed a meta-analysis on a database consisting of 146 studies including 127 species from four taxonomic groups. We tested for the effects of taxonomic group, experimental venue, developmental stage, UVB dosage and the latitude of organism provenance. Results UVB had significant negative effects on freshwater biota from the molecular-cellular to individual-population levels. However, these effects were highly variable among the taxonomic groups. In general, zooplankton was the most negatively affected group, whereas fish and amphibians were less affected. As direct fitness components, survival and reproduction were the two responses most affected by UVB. The sensitivities of individuals to UVB at different developmental stages were different for the same taxon, while the stage-dependent sensitivity patterns also differed among different taxa. Additionally, effects of different experimental venues, UVB dosages and latitudes of organism provenance on the effects of UVB were detected. Main conclusions Our results suggest that UVB has significant negative effects on freshwater biota. We found that the effects of UVB varied among taxonomic groups, developmental stages, experimental venues, UVB dosages and latitudes of organism provenance. The variation in sensitivity among the different taxa has important implications for ecosystem responses. Given that stratospheric ozone is unlikely to recover to the levels of the 1980s in the upcoming decades, more conservation efforts should be taken to protect freshwater habitats from further damage by UVB. [ABSTRACT FROM AUTHOR]

With the increasing levels of atmospheric ozone depletion, there has been much concern about the causal effects of high levels of ultraviolet radiation reaching the Earth's surface on skin cancer. This has led to growing interest in identifying new active ingredients for use in commercial sunscreens. In our study, the chemical compound 2-benzoyl-3-phenylquinoxaline 1,4-dioxide (BPQ) prepared by the Beirut reaction was tested for its ability to protect a human keratinocyte cell line (HaCaT) against ultraviolet B radiation (280-315 nm). We show that BPQ exhibited strong absorbance in the UVB range, with an overall absorption spectrum very similar to that of Padimate-O, a well-known active ingredient used in commercial sunscreens. HaCaT cells, which were irradiated with UVB in the presence of multiple doses of BPQ, exhibited, in a dose-dependent fashion, a significantly higher viability and lower oxidative stress levels than cells irradiated in the absence of drug. Our results show that BPQ is a potential photoprotective drug that holds great promise for use as an active ingredient in commercial sunscreens. [ABSTRACT FROM AUTHOR]

Light quantity and quality modulate grapevine development and influence berry metabolic processes. Here we studied light as an information signal for developing and ripening grape berries. A Vitis vinifera Sauvignon Blanc field experiment was used to identify the impacts of UVB on core metabolic processes in the berries under both high light (HL) and low light (LL) microclimates. The primary objective was therefore to identify UVB-specific responses on berry processes and metabolites and distinguish them from those responses elicited by variations in light incidence. Canopy manipulation at the bunch zone via early leaf removal, combined with UVB-excluding acrylic sheets installed over the bunch zones resulted in four bunch microclimates: (1) HL (control); (2) LL (control); (3) HL with UVB attenuation and (4) LL with UVB attenuation. Metabolite profiles of three berry developmental stages showed predictable changes to known UV-responsive compound classes in a typical UV acclimation (versus UV damage) response. Interestingly, the berries employed carotenoids and the associated xanthophyll cycles to acclimate to UV exposure and the berry responses differed between HL and LL conditions, particularly in the developmental stages where berries are still photosynthetically active. The developmental stage of the berries was an important factor to consider in interpreting the data. The green berries responded to the different exposure and/or UVB attenuation signals with metabolites that indicate that the berries actively managed its metabolism in relation to the exposure levels, displaying metabolic plasticity in the photosynthesis-related metabolites. Core processes such as photosynthesis, photo-inhibition and acclimation were maintained by differentially modulating metabolites under the four treatments. Ripe berries also responded metabolically to the light quality and quantity, but mostly formed compounds (volatiles and polyphenols) that have direct antioxidant and/or "sunscreening" abilities. The data presented for the green berries and those for the ripe berries conform to what is known for UVB and/or light stress in young, active leaves and older, senescing tissues respectively and provide scope for further evaluation of the sink/source status of fruits in relation to photosignalling and/or stress management. [ABSTRACT FROM AUTHOR]

PurposeIn this paper, the contribution of different genes involved in DNA repair for both survival and SOS induction inEscherichia colimutants exposed to ultraviolet B radiation (UVB, [wavelength range 280–315 nm]) was evaluated. Materials and methodsE. colistrains defective inuvrA,oxyR,recO,recN,recJ,exoX,recB,recDorxonAgenes were used to determine cell survival. All strains also had the geneticsulA::lacZfusion, which allowed for the quantification of SOS induction through the SOS Chromotest. ResultsFive gene products were particularly important for survival, as follows: UvrA > RecB > RecO > RecJ > XonA. Strains defective inuvrAandrecJgenes showed elevated SOS induction compared with the wild type, which remained stable for up to 240 min after UVB-irradiation. In addition,E. colistrains carrying therecOorrecNmutation showed no SOS induction. ConclusionsThe nucleotide excision and DNA recombination pathways were equally used to repair UVB-induced DNA damage inE. colicells. ThesulAgene was not turned off in strains defective in UvrA and RecJ. RecO protein was essential for processing DNA damage prior to SOS induction. In this study, the roles of DNA repair proteins and their contributions to the mechanisms that induce SOS genes inE. coliare proposed. [ABSTRACT FROM PUBLISHER]

Background Mesenchymal stem cells ( MSCs) are promising therapeutic agents for various diseases. Aims To investigate the effects of conditioned medium from human bone marrow-derived mesenchymal stem cells ( MSC-CdM) on pro-collagen production and wrinkle formation, we performed in vitro and in vivo experiments. Methods We assessed the effects of MSC-CdM on proliferation and photo-aging in human dermal fibroblasts after UVB exposure using enzyme activity assays for collagen type I secretion and MMP-1. To determine the effect of topically applied MSC-CdM on wrinkle formation, MSC-CdM (1% and 10%) and vehicle (propylene glycol: ethanol, 7 : 3) were applied to the dorsal skin of UVB-irradiated hairless mice for 8 weeks. We examined the effects on wrinkle formation by assessing visual skin grading, replica, tape stripping, transepidermal water loss ( TEWL), and skin hydration measurement. We also examined histology of the lesions using hematoxylin-eosin, Masson's trichrome, and immunohistochemical staining. Results MSC-CdM markedly reduced UV-induced matrix metalloproteinase-1 expression and increased pro-collagen synthesis in a dose-dependent manner. Our findings suggest that MSC-CdM induces repair of dermal damage and effacement of wrinkles on UVB-irradiated hairless mice through protective effect of hydration. Conclusion These results support an anti-wrinkle effect of MSC-CdM that involves increased collagen synthesis and suggest that MSC-CdM might be a potential candidate for preventing UV-induced skin damage. [ABSTRACT FROM AUTHOR]

Exposure to ultraviolet B (UVB; 280-320 nm) radiation induces the formation of reactive oxygen species (ROS) in the biological system. In this study, we examined the protective effect of carvacrol on UVB-induced lipid peroxidation and oxidative DNA damage with reference to alterations in cellular antioxidant status in human lymphocytes. A series of in vitro assays (hydroxyl radical, superoxide, nitric oxide, DPPH (2,2-Diphenyl-1-picryl hydrazyl), and ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assays) demonstrate antioxidant property of carvacrol in our study. UVB exposure significantly increased thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LHPs), % tail DNA and tail moment; decreased % cell viability and antioxidant status in UVB-irradiated lymphocytes. Treatment with carvacrol 30min prior to UVB-exposure resulted in a significant decline of TBARS, LHP, % tail DNA, and tail moment and increased % cell viability as carvacrol concentration increased. UVB irradiated lymphocytes with carvacrol alone (at 10 μg/mL) gave no significant change in cell viability, TBARS, LHP, % tail DNA, and tail moment when compared with normal lymphocytes. On the basis of our results, we conclude that carvacrol, a dietary antioxidant, mediates its protective effect through modulation of UVB-induced ROS. [ABSTRACT FROM AUTHOR]

Since olive oil has been reported to be a potent antioxidant, we examined its effects on Swiss albino mice. Olive oil was applied topically before repeated exposure of the mice to UVB. Histological data indicated that penetration of the olive oil into the skin of the mice was direct correlated with the time of exposure to UVB radiation. Additional experiments will be required to demonstrate the ability of olive oil to inhibit DNA damage induced by UVB. [ABSTRACT FROM AUTHOR]

Many amphibian species are dependent on ex situ conservation interventions for their long-term persistence. However, projects have been jeopardised by husbandry issues involving poor calcium metabolism and nutritional metabolic bone disease ( NMBD). Healthy calcium metabolism requires appropriate dietary calcium content and access to vitamin D3. In many animals, vitamin D3 can be photobiosynthesised in skin exposed to UVB radiation, as well as extracted from the diet, but the extent of vitamin D3 photobiosynthesis in amphibians is poorly known. Additionally, prey insects for captive amphibians are deficient in calcium and calcium content must be artificially increased, but the effects of different levels of augmentation and their interaction with UVB exposure are also little understood. We fed captive fire-bellied toads ( Bombina orientalis) with crickets augmented to contain 5% and 10% calcium and housed them with and without UVB exposure. Despite additional dietary vitamin D3 supplementation, we found that toads exposed to UVB radiation exhibited significantly higher serum vitamin D3 levels, indicating that this species may partly rely on photobiosynthesis sources of vitamin D3. These data are the first to show a direct link between UVB exposure and serum vitamin D3 in an amphibian. We found significant positive effects of UVB exposure and 10% dietary calcium content on skeletal structure, as well as complex interactions between treatments. We also found UVB radiation exposure resulted in more rapid natural coloration acquisition. Together, this indicates that standard calcium plus vitamin D3 supplementation methods may not fully substitute for UVB exposure and for increased feeder insect calcium content. This may have implications for the success of ex situ amphibian conservation, as well as for the welfare of captive amphibians in general. Our data lend support for the provision of UVB radiation for captive, basking amphibians. [ABSTRACT FROM AUTHOR]