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Molecules (Basel, Switzerland) Nov 2022Seaweeds are macroscopic, multicellular, eukaryotic and photosynthetic organisms, and are a source of chemical diversity with powerful biological activities for... (Review)
Review
Seaweeds are macroscopic, multicellular, eukaryotic and photosynthetic organisms, and are a source of chemical diversity with powerful biological activities for diversified industrial applications including cosmeceuticals. Red seaweeds (Rhodophyta) are good sources of Mycosporine-like amino acids (MAA) for photoprotectant and antiphotoaging compounds. In addition, Rhodophyta are also good sources for hydrogel compounds that are used widely in the food, pharmaceutical and cosmeceutical industries as gelling agents, moisturizers or for their antiphotoaging effects. Our survey and ongoing studies revealed that the biodiversity of Indonesian Rhodophyta is rich and is a treasure trove for cosmeceutical agents including MAA and hydrogels. This study delivers valuable information for identifying potential red seaweeds in screening and searching for cosmeceutical agents.
Topics: Cosmeceuticals; Hydrogels; Rhodophyta; Seaweed; Amino Acids
PubMed: 36431889
DOI: 10.3390/molecules27227788 -
Antioxidants (Basel, Switzerland) Jun 2019Little is known on the antioxidant activity modulation in microalgae, even less in diatoms. Antioxidant molecule concentrations and their modulation in microalgae has...
Little is known on the antioxidant activity modulation in microalgae, even less in diatoms. Antioxidant molecule concentrations and their modulation in microalgae has received little attention and the interconnection between light, photosynthesis, photoprotection, and antioxidant network in microalgae is still unclear. To fill this gap, we selected light as external forcing to drive physiological regulation and acclimation in the costal diatom . We investigated the role of light regime on the concentration of ascorbic acid, phenolic compounds and among them flavonoids and their connection with photoprotective mechanisms. We compared three high light conditions, differing in either light intensity or wave distribution, with two low light conditions, differing in photoperiod, and a prolonged darkness. The change in light distribution, from sinusoidal to square wave distribution was also investigated. Results revealed a strong link between photoprotection, mainly relied on xanthophyll cycle operation, and the antioxidant molecules and activity modulation. This study paves the way for further investigation on the antioxidant capacity of diatoms, which resulted to be strongly forced by light conditions, also in the view of their potential utilization in nutraceuticals or new functional cosmetic products.
PubMed: 31159429
DOI: 10.3390/antiox8060154 -
Journal of Cosmetic Dermatology Nov 2021Pathophysiology of rosacea is not completely understood and involves a complex interaction among genetics, ultraviolet (UV) light, microorganisms, impaired skin barrier,... (Review)
Review
BACKGROUND
Pathophysiology of rosacea is not completely understood and involves a complex interaction among genetics, ultraviolet (UV) light, microorganisms, impaired skin barrier, neuronal and vascular dysfunction, and immune system disruption.
AIMS
To describe the etiology of rosacea with an emphasis on the role of UV radiation and exposome, and to review the importance of non-pharmacologic strategies focusing on photoprotection.
METHODS
We conducted a narrative review of the literature. We performed literature searches with PubMed from January 1990 to November 2020 using the keywords "rosacea", "pathogenesis", "ultraviolet radiation", "exposome", "photoprotection", "sunscreens" and "non-pharmacologic agents". The search was limited to English, Spanish, and French language articles.
RESULTS
Several environmental factors such as UV light, diverse microorganisms, air pollution, tobacco smoking, nutrition, and psychological stress showed to trigger or worsen rosacea. UV radiation was reported to induce pro-inflammatory, pro-angiogenic, and pro-fibrotic responses. We found 6 original articles about the impact of sunscreens on rosacea. The use of sunscreens containing ingredients with emollient, anti-inflammatory, and/or vasoregulatory properties was shown to significantly improve symptomatology.
CONCLUSION
UV radiation and the exposome play a key role in the development of rosacea. UV light is implicated in all significant aspects of rosacea: skin inflammation, neoangiogenesis, telangiectasia, and fibrosis, and may even initiate rosacea. While the use of sunscreens is widely recommended, the literature on the impact of photoprotection in rosacea is scarce. Adequately formulated sunscreens could not only provide the required level of photoprotection, but may also help to mitigate the barrier dysfunction, neutralize facial redness (tinted sunscreens), and decrease inflammation and vascular dysfunction.
Topics: Exposome; Humans; Rosacea; Skin; Sunscreening Agents; Ultraviolet Rays
PubMed: 33626227
DOI: 10.1111/jocd.14020 -
Frontiers in Plant Science 2022Light intensity is highly heterogeneous in nature, and plants have evolved a series of strategies to acclimate to dynamic light due to their immobile lifestyles....
Light intensity is highly heterogeneous in nature, and plants have evolved a series of strategies to acclimate to dynamic light due to their immobile lifestyles. However, it is still unknown whether there are differences in photoprotective mechanisms among different light-demanding plants in response to dynamic light, and thus the role of non-photochemical quenching (NPQ), electron transport, and light energy allocation of photosystems in photoprotection needs to be further understood in different light-demanding plants. The activities of photosystem II (PSII) and photosystem I (PSI) in shade-tolerant species , intermediate species , and sun-demanding species were comparatively measured to elucidate photoprotection mechanisms in different light-demanding plants under dynamic light. The results showed that the NPQ and PSII maximum efficiency ( '/ ') of were higher than the other two species under dynamic high light. Meanwhile, cyclic electron flow (CEF) of sun plants is larger under transient high light conditions since the slope of post-illumination, P700 dark reduction rate, and plastoquinone (PQ) pool were greater. NPQ was more active and CEF was initiated more readily in shade plants than the two other species under transient light. Moreover, sun plants processed higher quantum yield of PSII photochemistry (Φ), quantum yield of photochemical energy conversion [Y(I)], and quantum yield of non-photochemical energy dissipation due to acceptor side limitation (Y(NA), while the constitutive thermal dissipation and fluorescence (Φ) and quantum yield of non-photochemical energy dissipation due to donor side limitation [Y(ND)] of PSI were higher in shade plants. These results suggest that sun plants had higher NPQ and CEF for photoprotection under transient high light and mainly allocated light energy through Φ and Φ, while shade plants had a higher Φ and a larger heat dissipation efficiency of PSI donor. Overall, it has been demonstrated that the photochemical efficiency and photoprotective capacity are greater in sun plants under transient dynamic light, while shade plants are more sensitive to transient dynamic light.
PubMed: 35463455
DOI: 10.3389/fpls.2022.819843 -
Eye (London, England) Feb 2017In recent years, manufacturers and distributors have promoted commercially available intraocular lenses (IOLs) with transmittance properties that filter visible... (Review)
Review
In recent years, manufacturers and distributors have promoted commercially available intraocular lenses (IOLs) with transmittance properties that filter visible short-wavelength (blue) light on the basis of a putative photoprotective effect. Systematic literature review. Out of 21 studies reporting on outcomes following implantation of blue-light-filtering IOLs (involving 8914 patients and 12 919 study eyes undergoing cataract surgery), the primary outcome was vision, sleep pattern, and photoprotection in 9 (42.9%), 9 (42.9%), and 3 (14.2%) respectively, and, of these, only 7 (33.3%) can be classed as high as level 2b (individual cohort study/low-quality randomized controlled trials), all other studies being classed as level 3b or lower. Of the level 2b studies, only one (14.3%) found in favor of blue-light-filtering IOLs vs ultraviolet (UV)-only filtering IOLs on the basis of an association between better post-operative contrast sensitivity (CS) at select frequencies with the former; however, that study did not measure or report CS preoperatively in either group, and the finding may simply reflect better preoperative CS in the eyes scheduled to be implanted with the blue-light-filtering IOL; moreover, that study failed to measure macular pigment, a natural preceptoral filter of blue-light, augmentation of which is now known to improve CS. In terms of photoprotection, there is no level 2b (or higher) evidence in support of blue filtering IOLs vs UV-only filtering IOLs. On the basis of currently available evidence, one cannot advocate for the use of blue-light-filtering IOLs over UV-only filtering IOLs.
Topics: Contrast Sensitivity; Evidence-Based Medicine; Filtration; Humans; Lens Implantation, Intraocular; Lenses, Intraocular; Radiation Protection; Retinal Pigments; Scattering, Radiation
PubMed: 27935597
DOI: 10.1038/eye.2016.266 -
Frontiers in Plant Science 2016Melatonin has been detected in numerous plant species. A particularly surprising finding concerns the highly divergent levels of melatonin that vary between species,... (Review)
Review
Melatonin has been detected in numerous plant species. A particularly surprising finding concerns the highly divergent levels of melatonin that vary between species, organs and environmental conditions, from a few pg/g to over 20 μg/g, reportedly up to 200 μg/g. Highest values have been determined in oily seeds and in plant organs exposed to high UV radiation. The divergency of melatonin concentrations is discussed under various functional aspects and focused on several open questions. This comprises differences in precursor availability, catabolism, the relative contribution of isoenzymes of the melatonin biosynthetic pathway, and differences in rate limitation by either serotonin N-acetyltransferase or N-acetylserotonin O-methyltransferase. Other differences are related to the remarkable pleiotropy of melatonin, which exhibits properties as a growth regulator and morphogenetic factor, actually debated in terms of auxin-like effects, and as a signaling molecule that modulates pathways of ethylene, abscisic, jasmonic and salicylic acids and is involved in stress tolerance, pathogen defense and delay of senescence. In the context of high light/UV intensities, elevated melatonin levels exceed those required for signaling via stress-related phytohormones and may comprise direct antioxidant and photoprotectant properties, perhaps with a contribution of its oxidatively formed metabolites, such as N (1)-acetyl-N (2)-formyl-5-methoxykynuramine and its secondary products. High melatonin levels in seeds may also serve antioxidative protection and have been shown to promote seed viability and germination capacity.
PubMed: 26925091
DOI: 10.3389/fpls.2016.00198 -
Anais Brasileiros de Dermatologia 2018The greatest sun exposure occurs until adolescence and this is the only factor involved in photocarcinogenesis subject to modification with photoprotection.
BACKGROUND
The greatest sun exposure occurs until adolescence and this is the only factor involved in photocarcinogenesis subject to modification with photoprotection.
OBJECTIVE
The objective of this study was to evaluate the habits and knowledge of adolescents regarding photoprotection.
METHOD
Cross-sectional study that included 512 students from primary and high school. Data were collected by questionnaires with questions about habits and knowledge on sun protection. For data analysis, Pearson's Chi-square test and Yates test were applied, with 5% level of significance.
RESULTS
We evaluated 512 students, with a mean age of 14 years old. The teenagers agreed that ultraviolet rays cause skin cancer and aging (96% and 70%, respectively). Knowledge about the occurrence of burns even on cloudy days was recorded in 68% of cases, as well as the need for photoprotection for sports in 72%. The source of information about sun protection were by parents in 55%. In 70% was observed previous occurrence of sunburn, the daily use of sunscreens was found in 15% and 67% used only at the beach. of sunscreens with SPF higher than 30 was reported by 70% of students and 57% reported going to the beach between 10h and 16h. In 68% of cases it was registered insufficient sun protection, attributed, in 57% of the time to forgetfulness.
STUDY LIMITATIONS
The sample refers to two schools of Curitiba (PR), Brazil.
CONCLUSION
Teenagers know the risks of sun exposure, but they do not adopt the practices for adequate protection.
Topics: Adolescent; Adolescent Behavior; Brazil; Cross-Sectional Studies; Environmental Exposure; Female; Health Knowledge, Attitudes, Practice; Humans; Male; Sunburn; Sunlight; Sunscreening Agents; Surveys and Questionnaires
PubMed: 29641695
DOI: 10.1590/abd1806-4841.20185489 -
Communications Biology Feb 2022Light-harvesting complexes (LHCs) are pigment-protein complexes whose main function is to capture sunlight and transfer the energy to reaction centers of photosystems....
Light-harvesting complexes (LHCs) are pigment-protein complexes whose main function is to capture sunlight and transfer the energy to reaction centers of photosystems. In response to varying light conditions, LH complexes also play photoregulation and photoprotection roles. In algae and mosses, a sub-family of LHCs, light-harvesting complex stress-related (LHCSR), is responsible for photoprotective quenching. Despite their functional and evolutionary importance, no direct structural information on LHCSRs is available that can explain their unique properties. In this work, we propose a structural model of LHCSR1 from the moss P. patens, obtained through an integrated computational strategy that combines homology modeling, molecular dynamics, and multiscale quantum chemical calculations. The model is validated by reproducing the spectral properties of LHCSR1. Our model reveals the structural specificity of LHCSR1, as compared with the CP29 LH complex, and poses the basis for understanding photoprotective quenching in mosses.
Topics: Amino Acid Sequence; Bryopsida; Computer Simulation; Gene Expression Regulation, Plant; Light-Harvesting Protein Complexes; Pigments, Biological; Protein Conformation; Stress, Physiological
PubMed: 35177775
DOI: 10.1038/s42003-022-03083-8 -
Marine Drugs Dec 2023Marine macroalgae (seaweeds) are important primary global producers, with a wide distribution in oceans around the world from polar to tropical regions. Most of these... (Review)
Review
Marine macroalgae (seaweeds) are important primary global producers, with a wide distribution in oceans around the world from polar to tropical regions. Most of these species are exposed to variable environmental conditions, such as abiotic (e.g., light irradiance, temperature variations, nutrient availability, salinity levels) and biotic factors (e.g., grazing and pathogen exposure). As a result, macroalgae developed numerous important strategies to increase their adaptability, including synthesizing secondary metabolites, which have promising biotechnological applications, such as UV-absorbing Mycosporine-Like Amino Acid (MAAs). MAAs are small, water-soluble, UV-absorbing compounds that are commonly found in many marine organisms and are characterized by promising antioxidative, anti-inflammatory and photoprotective properties. However, the widespread use of MAAs by humans is often restricted by their limited bioavailability, limited success in heterologous expression systems, and low quantities recovered from the natural environment. In contrast, bloom-forming macroalgal species from all three major macroalgal clades (Chlorophyta, Phaeophyceae, and Rhodophyta) occasionally form algal blooms, resulting in a rapid increase in algal abundance and high biomass production. This review focuses on the bloom-forming species capable of producing pharmacologically important compounds, including MAAs, and the application of proteomics in facilitating macroalgal use in overcoming current environmental and biotechnological challenges.
Topics: Humans; Seaweed; Ultraviolet Rays; Seasons; Amino Acids; Rhodophyta
PubMed: 38132954
DOI: 10.3390/md21120633 -
Plants (Basel, Switzerland) Jan 2022Human skin works as a barrier against the adverse effects of environmental agents, including ultraviolet radiation (UVR). Exposure to UVR is associated with a variety of... (Review)
Review
Human skin works as a barrier against the adverse effects of environmental agents, including ultraviolet radiation (UVR). Exposure to UVR is associated with a variety of harmful effects on the skin, and it is one of the most common health concerns. Solar UVR constitutes the major etiological factor in the development of cutaneous malignancy. However, more than 90% of skin cancer cases could be avoided with appropriate preventive measures such as regular sunscreen use. Plants, constantly irradiated by sunlight, are able to synthesize specialized molecules to fight against UVR damage. Phenolic compounds, alkaloids and carotenoids constitute the major plant secondary metabolism compounds with relevant UVR protection activities. Hence, plants are an important source of molecules used to avoid UVR damage, reduce photoaging and prevent skin cancers and related illnesses. Due to its significance, we reviewed the main plant secondary metabolites related to UVR protection and its reported mechanisms. In addition, we summarized the research in Mexican plants related to UV protection. We presented the most studied Mexican plants and the photoprotective molecules found in them. Additionally, we analyzed the studies conducted to elucidate the mechanism of photoprotection of those molecules and their potential use as ingredients in sunscreen formulas.
PubMed: 35050108
DOI: 10.3390/plants11020220