Search Results (646)

Ultraviolet (UV) radiation is a main environmental factor responsible for skin damage, leading to oxidative stress, inflammation, and impairment of the skin barrier function. Furthermore, many components in sunscreen may accumulate in aquatic systems, causing environmental pollution. Therefore, the identification of novel natural bioactives that counteract these effects and can be useful as effective adjuvants in sunscreen formulations is of particular interest. Morin (1), a natural flavonoid, represents an attractive scaffold for modifications to enhance its biological activity. Herein, we aimed to investigate the effects of combining the flavonoid 1 and its derivative, morin semicarbazone (2), with the carotenoid fucoxanthin (FX) on UVB-exposed HaCaT keratinocytes. All compounds exhibited higher radical scavenging activity compared to Trolox. In this cell model, the phenolic–carotenoid combinations provided greater photoprotection than individual compounds, significantly enhancing cell viability and reducing necrosis, FX-2 emerged as the most potent combination, as evidenced by a marked reduction in reactive oxygen species (ROS) and malondialdehyde (MDA) levels, likely mediated through the activation of the nuclear factor erythroid 2-related factor 2/Heme oxygenase-1 (Nrf2/HO-1) signaling pathway. Furthermore, the tested treatments exerted enhanced anti-inflammatory effects by significantly reducing interleukin-6 (IL-6), cyclooxygenase 2 (COX-2), and matrix metalloproteinase-9 (MMP-9) mediators, with FX-2 being the most active combination. In conclusion, our findings highlight the protective effects of the combinations of these phenolics with the carotenoid FX against UVB radiation and support their potential application as natural active ingredients in sunscreen formulations. Full article

Rapeseed (Brassica napus L.) is a globally important oilseed crop; however, its ‘double-low’ cultivars exhibit substantially reduced glucosinolate levels in vegetative tissues. To investigate whether UV-B radiation could be used to enhance glucosinolate accumulation, we systematically examined the modulation of glucosinolate profiles and associated biosynthetic pathways in leaves of the ‘double-low’ cultivar NY4 under white light (WL) supplemented with two UV-B intensities: low-intensity UV-B (UVBL, 0.1 W m⁻²) and high-intensity UV-B (UVBH, 0.4 W m⁻²). Rapeseed seedlings were treated for 21 days under a 16 h photoperiod, and leaf samples were collected at the end of the treatment period, with three biological replicates per condition. Compared with the WL control, UVBL significantly increased total glucosinolate content by 64.57%, driven predominantly by elevated accumulation of progoitrin and neoglucobrassicin. In contrast, UVBH reduced total glucosinolate levels but markedly elevated gluconasturtiin content. Transcriptome analysis revealed that UVBL upregulated key genes involved in glucosinolate biosynthesis (e.g., MAM, IPMDH, CYP79F1, and SOT17/18) and transcription factors (e.g., MYB28, MYB34, MYB51, and MYB122). Conversely, UVBH downregulated genes associated with side-chain elongation of aliphatic glucosinolates and secondary modification of indolic glucosinolate. Collectively, these results demonstrate that low-intensity UV-B radiation can effectively boost total glucosinolate content in rapeseed leaves via transcriptional reprogramming. Full article

Background/Objectives: Propolis is well recognized for its antioxidant, anti-inflammatory, and wound-healing properties, supporting its cutaneous application in phytopharmaceuticals for the management of ultraviolet B (UVB)-induced skin damage. However, the application of propolis is limited by its intense coloration, stickiness, and poor user convenience. In situ film-forming systems (FFS) represent a novel dosage form designed to overcome these challenges, although efficacy data for using FFS remains limited. Consequently, this study aimed to develop a propolis-based FFS and evaluate its efficacy in mitigating UVB-irradiated HaCaT keratinocytes. Methods: Apis mellifera propolis was macerated and analyzed for total phenolic content (TPC) and total flavonoid content (TFC), radical scavenging activity (DPPH assay), and nitric oxide scavenging capability. Bioactive compounds were identified using high-performance liquid chromatography analysis (HPLC). The propolis extract was formulated into FFS and investigated on UVB-damaged HaCaT keratinocytes. An MTT viability assay, propidium iodide flow cytometry for cell cycle analysis, and a scratch wound healing assay were used to evaluate the therapeutic effects of the FFS. Results: The 72 h macerated propolis extract contained high levels of TPC, TFC, and targeted phytochemicals. The propolis extract exhibited free radical scavenging and nitric oxide inhibitory activities. Seven formulations exhibited suitable performance, with formulation F7 (FFS-F7) demonstrating superior drying time and dose-dependent free radical scavenging. Notably, FFS-F7 (≥12.5 µg/mL) significantly enhanced HaCaT proliferation, mitigated UVB-induced cell cycle arrest, reduced cellular damage, and accelerated wound closure. Conclusions: This study successfully developed an FFS that not only overcomes these physical drawbacks but also preserves the biological activity of the extract. The significant protective and restorative effects against UVB-induced HaCaT damage demonstrate the therapeutic potential of Thai Apis mellifera propolis and establish the FFS as a versatile base with the potential for delivering other bioactive compounds. Full article

Ground-level ozone (GLO₃) poses a critical threat to public health and the success of the Saudi Green Initiative, yet its long-term spatiotemporal evolution across the Arabian Peninsula remains poorly constrained. Utilizing CAMS-derived mixing ratios (1000–850 hPa) from 2003 to 2024, this study identifies a major systemic regime shift occurring in 2016–2017, marking a transition toward a more O₃-enriched atmospheric state across Saudi Arabia. While the early study period was characterized by pronounced spatial heterogeneity, post-2017 diagnostics reveal a synchronized intensification of GLO₃, particularly within the urban industrial belts of the Eastern and Western Provinces. Statistical trend metrics, including Mann–Kendall and regime-shift detection, show a persistent upward trend in GLO₃ concentrations, most significantly during winter and over the southwestern highlands. These trends are robustly coupled with increasing boundary-layer height, temperature, and UV-B radiation, alongside shifting precursor stoichiometry (CO, VOCs, NO_x) that separates titration-dominated from production-dominated regimes. Our results suggest that this mid-decade intensification reflects a convergence of anthropogenic forcing under Saudi Vision 2030 and shifting regional climatic drivers. By uncovering the transition from localized variability to kingdom-wide synchronization, this research provides a process-based foundation for targeted air quality management and the safeguarding of regional sustainability frameworks. Full article

Ultraviolet B (UVB), as a major component of solar radiation, is a key factor in inducing skin photoaging. The epidermis serves as the primary defensive barrier of the skin and absorbs the majority of UVB. This study aims to elucidate the protective effect of Alk against UVB-induced photoaging and further uncover its underlying molecular mechanisms. In vitro, Alk-pretreated HaCaT cells were exposed to UVB. Cell viability, ROS, senescence, antioxidant enzymes, and protein expression were analyzed. Mechanisms were examined using CETSA, DARTS, Co-IP, and NRF2 knockout. In vivo, Alk hydrogel was tested in UVB-exposed BALB/c mice, with protection assessed via histology and immunohistochemistry. In vitro, Alk directly binds to Keap1, disrupts Keap1–Nrf2 interaction, promotes nuclear translocation of Nrf2, and upregulates the expression of its downstream target HO-1. Consequently, intracellular ROS generation is reduced, cellular senescence is alleviated, and the expression of inflammatory factors (TNF-$\alpha$, COX-2) and MMP-9 is suppressed. In vivo, topical application of the Alk hydrogel prevented UVB-induced skin thickening and collagen degradation. Alk exerts a preventive effect on UVB-induced photoaging in HaCaT cells and skin, providing strong support for developing Alk as a potential plant-derived active ingredient for preventing skin photoaging. Full article

The production and use of plastics have direct consequences on the environment, such as the greenhouse gas emissions (GHGs) they cause. Therefore, it is necessary to develop materials from renewable sources with a lower environmental impact to replace plastic. In this work, films with bioactive properties have been developed from cellulose nanofibers (CNFs) and natural phenolic compounds for food packaging applications. First, the optimization of the incorporation of three different natural phenolic compounds (tannic acid, p-coumaric acid, and acetosyringone) into nanocellulose was studied using a Box–Behnken design, with the phenols adsorbed by the nanocellulose as the output variable. Once the incorporation was optimized, films containing nanocellulose and phenolic compounds were produced and characterized. Tannic acid showed the best results with regard to the optical properties of the resulting films and achieved a complete blocking of UV-B radiation, as well as adding to nanocellulose antioxidant (4.32 mM TE/g film) and antibacterial capacity (log R of 6.6 ± 0.2 and 3.8 ± 0.1 for Staphylococcus aureus and Escherichia coli, respectively), making these films a promising material for use in contact with food as a packaging material, although more in-depth studies and measures are needed to make these films viable for use in food packaging. Full article

The impacts of climate change on Mediterranean weed flora were investigated to inform future weed management strategies. Projections indicate that rising temperatures and increased atmospheric CO₂ concentrations are likely to favor ruderal species characterized by rapid phenological development and high dispersal capacity. Enhanced abiotic stressors—such as elevated temperatures, water scarcity, and increased UV-B radiation—are expected to affect crops more severely than weeds, given the latter’s greater evolutionary potential to develop stress-tolerant biotypes. Moreover, the increased frequency and intensity of extreme events (e.g., drought, flooding, and soil salinization) may reduce weed community diversity, potentially leading to dominance by a limited number of highly competitive species and consequently intensifying reliance on chemical weed control. Simplification of weed communities may also increase vulnerability to the introduction and establishment of alien species, particularly those originating from hot and arid regions, some of which may be parasitic, toxic, or allergenic. Climate change-induced phenological mismatches between flowering plants and pollinators are likely to favor wind-pollinated weed species, further compromising the aesthetic and ecological quality of agricultural landscapes. Additionally, increased production of wind-dispersed allergenic pollen, together with the anticipated rise in herbicide applications, may pose significant risks to human health. An effective agronomic strategy to address future weed scenarios should include the genetic improvement in crops to enhance adaptive plasticity, exploiting germplasm from ancestral lines and related wild species. Full article

In an accelerated aging experiment involving a wide range of cumulative UV-B radiant exposures (up to approximately 9.46 × 10³ J cm⁻²), the degradation state of microplastics was assessed using SEM, FTIR, Raman spectroscopy, and DSC, and correlated with the cumulative UV-B dose. Sunlight-induced photooxidation is a significant weathering mechanism for microplastics. In this study, high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polyvinyl chloride (PVC), nylon, and polystyrene (PS) were exposed to UV-B radiation under controlled dry conditions at two irradiance levels (0.06 and 0.6 mW cm⁻²), covering cumulative UV-B radiant exposures of up to approximately 9.47 × 10³ J cm⁻². Degradation was evaluated using SEM, FTIR, Raman spectroscopy, and DSC, and was related to the cumulative UV-B dose (H). The extent and progression of degradation varied significantly among the polymers. Overall, FTIR provided the most sensitive assessment of photooxidative surface changes for HDPE, LDPE, PP, and PS, Raman spectroscopy was most diagnostic for PVC (particularly for dechlorination-related changes), and DSC-derived crystallinity was most informative for nylon. These dose-resolved datasets establish a reproducible reference framework (“degradation library”) to facilitate the comparative assessment of the relative photooxidative aging stage of microplastics under comparable surface UV-driven conditions. Outdoor “sunlight-equivalent” times are reported solely as order-of-magnitude contextualization due to environmental variability. Full article

Ultraviolet (UV) radiation from the sun causes adverse skin changes such as premature aging. UV-induced mitochondrial DNA (mtDNA) alterations, including deletions, contribute to photoaging and cellular dysfunction. While the most frequent mtDNA rearrangement is the common deletion (CD), characterized by the loss of nearly one-third of the genome (4977 bp), detailed knowledge of mechanisms governing UV-mediated initiation of the CD and mitigation strategies are lacking. Here, we investigated how increasing UV exposure increases CD levels in human skin fibroblasts via cellular reactive oxygen species (ROS) formation and mtDNA oxidation and demonstrated that antioxidant preconditioning of cells prevents UVA-induced CD accumulation. Conversely, UVB exposure induced cyclobutane pyrimidine dimers (CPDs) without affecting ROS, suggesting an ROS-independent pathway. Using a 3D full-thickness human skin model, we confirmed UVA-dependent CD formation in both the epidermis and dermis. RNA-Seq analysis of UVA-exposed fibroblasts revealed upregulation of mitochondrial DNA replication genes and downregulation of mtDNA repair genes. These findings provide insight into how UVA and UVB differ in detrimental effects on mtDNA, with UVA impacting mtDNA maintenance and transcription via a ROS-dependent mechanism, and provide a physiologically relevant platform to evaluate potential interventions. Full article

This study aims to develop and characterize novel dermatocosmetic formulations designed to hydrate the skin, improve its appearance, reduce wrinkles, and provide antioxidant, anti-ageing, antimicrobial, and anti-inflammatory benefits, along with potential protection against UVA and UVB radiation. The formulations contain the following ingredients: xanthan gum (0.5%), Calendula officinalis oil (5%), Argania spinosa oil (5%), Helianthus annuus oil (5%), liposomes containing a hydroalcoholic extract of pomace from local red or white grapes (2%), an olive oil-based emulsifier (6%), vitamin E (0.5%), cetearyl alcohol (3%), propylene glycol (8%), and purified water (up to 100%). The natural ingredients used in these formulations, i.e., the red or white grape pomace extract from the aforementioned Romanian varieties, the oils of Calendula officinalis, Argania spinosa, and Helianthus annuus, xanthan gum, and the olive oil-based emulsifier (Olliva), promote the concept of ‘green cosmetics’. The use of liposomes to deliver bioactive substances from hydroalcoholic extracts allows the gradual release of active ingredients into the skin. An alternative for incorporating grape pomace extract into a cream-type matrix involves the use of liposomes. Liposomes loaded with red or white grape pomace extract were prepared using the thin-film hydration technique, followed by ultrasonication and extrusion. The obtained formulations were characterized using bio-physico-chemical analysis procedures in terms of consistency, colour, homogeneity, aroma, pH, stretch, texture, stability, and antioxidant activity/free radical scavenging capacity, as well as in vitro polyphenol release behaviour. These newly developed dermatocosmetic formulations were the subject of a patent application in Romania. Full article

Background/Objectives: The primary mechanisms driving UV-induced carcinogenesis include DNA damage leading to mutations, and reactive oxygen species (ROS) formation that can cause inflammation, immunosuppression, alteration of the structure of proteins, including transcription factors, and carcinogenesis through epigenetic modifications. Curcumin has the potential to inhibit DNA-methyltransferases (DNMTs) and histone deacetylases (HDACs), but this has not been examined yet at the gene-expression level. In this article, we aimed to explore the potential protective effect of curcumin against UV radiation-induced DNMT1, DNMT3A, DNMT3B, HDAC5, and HDAC6 expression in immortalized keratinocytes (HaCaT), hepatocellular carcinoma (HepG2), and lung adenocarcinoma (A549) cells. Methods: Cells were exposed to UV-B radiation for different periods and treated with curcumin at different concentrations to evaluate dose-related trends in DNMT and HDAC gene expression compared with untreated UV-exposed cells. Results: UV exposure increased the DNMT and HDAC gene expression levels in the examined cells dose-dependently. Curcumin exposure resulted in decreased mRNA expression levels of DNMT and HDAC gene expression. In our experimental setup curcumin modulated the transcription of DNMT and HDAC genes in A549 and HaCaT cells in a dose-dependent manner. In HepG2 cells, UV-B induced a less pronounced, but still significant, increase in the examined gene expression levels. This effect was also dose-dependently decreased by curcumin, although less markedly. Conclusions: Future studies are warranted to examine if curcumin combined with other chemopreventive agents through the HDAC and DNMT inhibitory activity at the gene expression level can exert a synergistic effect and may potentially supplement cancer therapeutic strategies. Full article

Ultraviolet (UV) radiation induces DNA damage and oxidative stress in melanocytes, shaping pigmentation phenotypes and elevating photocarcinogenesis risk. Human models that capture donor-linked genetic determinants of UV sensitivity remain limited. Here, we establish a genotype-informed UV response model using induced pluripotent stem cell (iPSC)-derived melanocytes from donors carrying defined MC1R variants. Differentiated cells recapitulated melanocytic morphology, marker expression, and pigmentation consistent with donor sun-sensitivity traits. Following narrowband UVB exposure, melanocyte lines with higher UV sensitivity showed reduced survival, prolonged checkpoint activation, and CPD-associated DNA damage signaling dynamics. Mechanistic analysis suggests that the interferon-regulated GTPase MX2 is associated with amplification of UV-induced p53 and p38 activation while promoting apoptosis independently of AKT. These findings support MX2 as a physiological enhancer of DNA damage signaling in normal melanocytes, distinct from its interferon-mediated role in melanoma. Our study provides a human-relevant platform linking pigmentation genotype to UV resilience and supports iPSC-derived systems as new approach methodologies (NAMs) for mechanistic and translational phototoxicology. Full article

Ultraviolet-B (UV-B) radiation plays a pivotal role in plant growth, metabolism, and the accumulation of bioactive compounds, but its effects under greenhouse conditions are highly species- and dose-dependent. This study investigated the responses of eggplant (Solanum melongena L., cv. Lunga Napoletana) and lettuce (Lactuca sativa L., cv. Rosplus) cultivated under greenhouse films transmitting 3–39% of ambient UV-B. Leaf temperature was monitored throughout the growth cycle using infrared thermography, while physiological parameters (chlorophyll, flavonoids, anthocyanins, and nitrogen index) and post-harvest nutritional traits (antioxidant activity, vitamin C, carotenoids, and total chlorophyll) were assessed. Comparative analysis revealed species-specific responses. Eggplant exhibited peak nutraceutical quality at higher UV-B levels (35–39%) with minimal changes in yield, whereas lettuce achieved maximal yield and secondary metabolite accumulation under intermediate UV-B (30–35%). At the highest UV-B transmittance (39%), both species exhibited stable or slightly reduced thermal and physiological parameters, indicating dose-dependent regulatory mechanisms that maintain photoprotection and metabolic activity under elevated UV-B exposure. Results suggest an apparent optimal range of UV-B transmittance in greenhouse systems under the tested experimental conditions, contributing to improved crop productivity and nutritional quality. Full article

Plants respond to ultraviolet B radiation (280–320 nm) with an integrated reaction that includes the reception of the acting stress factor, followed by the generation of reactive oxygen species and damage to macromolecules and membrane structures, as well as changes in cellular metabolism and the formation of protective systems. However, the involvement of key UV-B–related signalling components such as HY5, SPA1 and BIC1 or BIC2 proteins in physiological, biochemical and molecular responses remains insufficiently understood. The effects of 8, 16 and 24 h of UV-B exposure (within an 8 h photoperiod over three days) on the net photosynthetic rate (Pn), chlorophyll fluorescence parameters Y(II) and F_v/F_m, reflecting the functional state of PSII, nonphotochemical quenching (NPQ), pigment contents (Chl(a+b), carotenoids, anthocyanins and UV-absorbing pigments (UAPs) and the expression of key light-induced genes in wild-type Arabidopsis thaliana and spa1, bic1,2 and hy5 mutants were studied. UV-B irradiation resulted in a gradual reduction in the Pn, Y(II), F_v/F_m values and Chl(a+b) but caused a marked increase in the anthocyanin and UAP contents and only minor changes in the carotenoid content. The hy5 mutant presented the lowest net photosynthetic rate (Pn), chlorophyll fluorescence parameters, and chlorophyll and carotenoid contents under all the UV-B exposures. In addition, the accumulation of anthocyanins and UAPs during UV-B treatment was consistently the lowest in hy5. After any UV-B exposure, the highest accumulation of UAPs and anthocyanins was observed in the spa1 mutant, whereas the highest Pn values were detected after 24 h in bic1,2. One of the reasons for the reduced photosynthetic activity and antioxidant capacity in hy5 may be the lower expression levels of CHS and PAL in this variety than in the other genotypes. Our results indicate that HY5 is required to maintain antioxidant responses and photosynthetic performance under repeated daytime UV-B exposure (16.8 kJ m⁻² per day). In contrast, BIC1, BIC2, and SPA1 also contribute to UV-B tolerance, but through distinct regulatory mechanisms and to a lesser extent. Full article

In the context of global climate change, clarifying the effects of climatic factors on the potential distribution of forage grass species is critical for grassland development and ecological management. In this study, Phleum pratense was selected as the focal species, and an ensemble species distribution modeling framework was developed using the Biomod2 platform. After excluding highly correlated environmental variables, 17 ecologically meaningful predictors were retained to project the potential habitat suitability patterns of P. pratense and their future dynamics. The results indicate that the ensemble model achieved high predictive accuracy. Annual mean UV-B radiation, mean temperature of the driest quarter, and precipitation of the coldest quarter were identified as the primary climatic factors shaping the potential distribution of P. pratense. Under current climatic conditions, highly suitable habitats occupy a relatively limited and fragmented area, whereas low- and moderately suitable habitats predominate. Under future climate scenarios, increasing emission levels are associated with an overall contraction of moderately and highly suitable areas, accompanied by a continuous expansion of unsuitable habitats. In addition, the centroid of highly suitable habitats is projected to shift northwestward. These findings suggest that climate change may substantially alter the potential suitable range of P. pratense by modifying key climatic gradients and stress-period conditions. Overall, this study provides a scientific basis for the utilization of P. pratense germplasm resources and the sustainable development of plateau grassland systems. Full article