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photoprotection Knowledge and Photoprotective Behavior of University Students:A Cross-sectional Study in Indonesia

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International Journal of Dermatology and Venereology 2022年第3期5卷 140-148页

作者： Regina Stefani Roren Paulus Mario Christopher Nana Novia Jayadi Department of Dermatology and Venereology Faculty of MedicinePelita Harapan UniversityBanten 15810Indonesia

Objective:Awareness regarding the negative effects of ultraviolet radiation are commonly neglected in Asian *** study sought to evaluate the ultraviolet radiation knowledge and photoprotective behaviors of university students in ***:This observational cross-sectional was conducted at Pelita Harapan University,***:A total of 89(45.4%)medical students and 107(54.6%)nonmedical students participated in this *** mean age was 21.03±2.03 years,and 46.4%of them had Fitzpatrick type III *** students as well as older students exhibited a higher level of knowledge regarding photoprotection(P≤0.05).Factors related to good photoprotective behaviors were sex,older age,and average expenditure on *** analysis revealed that a high level of knowledge regarding photoprotection was related to acceptable photoprotective behaviors(P=0.01;odds ratio=1.97;95%confidence interval=1.13-3.54).Conclusions:Knowledge regarding sun-related damage and practice of photoprotective behaviors were low among the *** results indicate that formal education and academic subjects should incorporate the topic of sun-related damage and promote the practice of photoprotective behaviors early on to increase awareness among populations.

关键词： sun exposure ultraviolet radiation photoprotection sunscreen knowledge behavior university students

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Contribution of the Alternative Respiratory Pathway to PSII photoprotection in C3 and C4 Plants

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Molecular Plant 2017年第1期10卷 131-142页

作者： Zi-Shan Zhang Mei-Jun Liu Renate Scheibe Jennifer Selinski Li-Tao Zhang Cheng Yang Xiang-Long Meng Hui-Yuan Gao State Key Laboratory of Crop Biology ColLege of Life Sciences College of Horticulture Science and Engineering Shandong Agricultural University Tai'an-271018 China Department of Plant Physiology FB5 University of Osnabrueck 49069 Osnabrueck Germany National and Local Joint Engineering Laboratory of Ecological Mariculture Institute of Oceanology Chinese Academy of Sciences 7 Nanhai Road Qingdao 266071 China Wheat Research Institute Henan Academy of Agricultural Sciences Zhengzhou Henan 450002 China These authors contributed equally te this article.

The mechanism by which the mitochondrial alternative oxidase （AOX） pathway contributes to photosystem II （PSII） photoprotection is in dispute. It was generally thought that the AOX pathway protects photosystems by dissipating excess reducing equivalents exported from chloroplasts through the malate/oxaloacetate （Mal/OAA） shuttle and thus preventing the over-reduction of chloroplasts. In this study, using the aoxla Arabidopsis mutant and nine other C3 and C4 plant species, we revealed an additional action model of the AOX pathway in PSII photoprotection. Although the AOX pathway contributes to PSII photoprotection in C3 leaves treated with high light, this contribution was observed to disappear when photorespiration was suppressed. Disruption or inhibition of the AOX pathway significantly decreased the photorespiration in C3 leaves. Moreover, the AOX pathway did not respond to high light and contributed little to PSII photoprotection in C4 leaves possessing a highly active Mal/OAA shuttle but with little photorespiration. These results demonstrate that the AOX pathway contributes to PSII photoprotection in C3 plants by maintaining photo- respiration to detoxify glycolate and via the indirect export of excess reducing equivalents from chloro-plasts by the MaI/OAA shuttle. This new action model explains why the AOX pathway does not contribute to PSII photoprotection in C4 plants.

关键词： alternative oxidase photoprotection photosystem II photorespiration C3 plant C4 plant

The Arabidopsis Spontaneous Cell Death1 gene, encoding a ζ-carotene desaturase essential for carotenoid biosynthesis, is involved in chloroplast development, photoprotection and retrograde signalling

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Cell Research 2007年第6期17卷 458-470页

作者： Haili Dong1,2 Yan Deng1,2 Jinye Mu1 Qingtao Lu3 Yiqin Wang1 Yunyuan Xu3 Chengcai Chu1 Kang Chong3 Congming Lu3 Jianru Zuo1 1 State Key Laboratory of Plant Genomics and National Plant Gene Research Center (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beoing 100101, China 2 Graduate School, Chinese Academy of Sciences, Beijing 100039, China 3 Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China InstituteofGeneticsandDevelopmentalBiologyChineseAcademyofSciencesBeijing100101China GraduateSchoolChineseAcademyofSciences Beijing

Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiologi-cal processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and chloroplast *** carotenoid biosynthesis has been well studied biochemically, the genetic basis of the pathway is not wellunderstood. Here, we report the characterization of two allelic Arabidopsis mutants, spontaneous cell death 1-1 (spcl-1)and spcl-2. The weak allele spcl-1 mutant showed characteristics of bleached leaves, accumulation of superoxide andmosaic cell death. The strong mutant allele spcl-2 caused a complete arrest of plant growth and development shortlyafter germination, leading to a seedling-lethal phenotype. Genetic and molecular analyses indicated that SPC1 encodesa putative ζ-carotene desaturase (ZDS) in the carotenoid biosynthesis pathway. Analysis of carotenoids revealed thatseveral major carotenoid compounds downstream of SPC1/ZDS were substantially reduced in spcl-1, suggesting thatSPC1 is a functional ZDS. Consistent with the downregulated expression of CAO and PORB, the chlorophyll contentwas decreased in spcl-1 plants. In addition, expression of Lhcb1.1, Lhcb1.4 and RbcS was absent in spcl-2, suggestingthe possible involvement of carotenoids in the plastid-to-nucleus retrograde signaling. The spcl-1 mutant also displaysan ABA-deficient phenotype that can be partially rescued by the externally supplied phytohormone. These results suggestthat SPC1/ZDS is essential for biosynthesis of carotenoids and plays a crucial role in plant growth and development.

关键词： carotenoid biosynthesis cell death chloroplast development photoprotection Arabidopsis SPC1/ZDS

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Enhanced photoprotection by Protein-Bound vs Free Xanthophyll Pools： A Comparative Analysis of Chlorophyll b and Xanthophyll Biosynthesis Mutants

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Molecular Plant 2010年第3期3卷 576-593页

作者： Luca Dall'Osto Stefano Cazzaniga Michel Havaux Roberto Bassi Dipartimento di Biotecnologie Universita di Verona Strada Le Grazie 15 37134 Verona Italy CEA IBEB SBVME Laboratoire d'Ecophysiologie Moldculaire des Plantes 13108 Saint-Paul-lez-Durance France CNRS UMR Biologie Vegetale et Microbiologie Environnementales 13108 Saint-Paul-lez-Durance France Universite Aix-Marseille 13108 Saint-Paul-lez-Durance France

When light absorbed by plants exceeds the capacity of photosynthesis, the xanthophyll violaxanthin is reversibly de-epoxidized to zeaxanthin in the so-called xanthophyll cycle. Zeaxanthin plays a key role in the protection of photosynthetic organisms against excess light, by promoting rapidly reversible （qE） and long-term （ql） quenching of excited chlorophylls, and preventing lipid oxidation. The photoprotective role of zeaxanthin, either free or bound to light-harvesting complexes （Lhcs）, has been investigated by using mutants lacking Chl b （chl） and/or specific xanthophyll species （npq, lut2）. The chl mutation causes （1） the absence of Lhcb proteins; （2） strong reduction of the feedback deexcitation （qE）; and （3） accumulation of xanthophylls as free pigments into thylakoids. Chl mutants showed extreme sensitivity to photo-oxidative stress in high light, due to higher singlet oxygen （102） release. The double mutant chlnpql was more sensitive to photo-oxidation than chl, showing that zeaxanthin does protect lipids even when free in the membrane. Nevertheless, lack of zeaxanthin had a much stronger impact on the level of lipid peroxidation in Lhcs-containing plants （WTvs npql） with respect to Lhc-less plants （chl vs chlnpql）, implying that its protective effect is enhanced by interaction with antenna proteins. It is proposed that the antioxidant capacity of zeaxanthin is empowered in the presence of PSII- LHCs-Zea complexes, while its effect on enhancement of qE only provides a minor contribution. Comparison of the sensitivity of WT vs npql plants to exogenous 102 suggests that besides the scavenging of 102, at least one additional mechanism is involved in chloroplast photoprotection.

关键词： Zeaxanthin singlet oxygen photoprotection chloroplast light-harvesting complexes.

Xanthophyll Cycle and Its Molecular Mechanism in photoprotection

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Acta Botanica Sinica 2002年第4期44卷 379-383页

作者：林荣呈许长成李良璧匡廷云中国科学院植物研究所光合作用基础研究开放实验室北京100093

When plants absorb more light than that can be used for photosynthesis, the excessive energy can cause photoinhibition and even photooxidation of photosynthetic apparatus. Xanthophyll cycle-dependent photo-protection is believed to be the main mechanism for plants to deal with excessive light energy. This review focuses on molecular biological aspects and regulations of violaxanthin de-epoxidase and zeaxanthin epoxidase involved in xanthophyll cycle. We will summarize the functions of xanthophyll cycle, especially recent advances in its thermal dissipation mechanism of photoprotection. Some interesting issues deserving further study will be discussed.

关键词： xanthophyll cycle violaxanthin de-epoxidase thermal dissipation photoprotection

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Effects of Drought Stress on the photoprotection in Ammopiptanthus mongolicus Leaves

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Acta Botanica Sinica 2002年第11期44卷 1309-1313页

作者：赵长明王根轩兰州大学干旱农业生态国家重点实验室兰州730000

Ammopiptanthus mongolicus (Maxim.) Cheng f. is one of the evergreen shrubs in the desert region of China. In midday its leaves bear photon flux density over 1 500 μmol·m -2 ·s -1 at natural habitat. They show the obvious phenomenon of photoinhibition. For the study of the effects of drought stress on the major protective mechanism against strong light in A. mongolicus leaves, the diurnal variations of photosynthetic rate and chlorophyll fluorescence parameters were investigated under natural conditions with portable photosynthetic measurement system (CIRAS_1) and portable fluorometer (MFMS_2). The experimental results showed that, under normal and drought stress conditions,the net photosynthetic rate ( Pn ), the primary maximum photochemical efficiency of PSⅡ ( Fv/Fm ) and the quantum efficiency of noncyclic electron transport of PSⅡ ( Φ PSⅡ ) decreased obviously at noon (Figs.2,3A,4B). In comparison with plants under normal condition, under drought stress minimal chlorophyll fluorescence ( Fo ) decreased at first and then increased (Fig.3A), non_photochemical quenching ( NPQ ) quickly increased and sustained at a higher level (Fig.4B). This indicated that the major photoprotective mechanism of A. mongolicus leaves was the xanthophyll cycle_dependent thermal energy dissipation under normal condition, while under drought stress, the major photoprotective mechanism was both the xanthophyll cycle_dependent thermal energy dissipation and the reversible inactivation of PSⅡ reaction center.

关键词： Ammopiptanthus mongolicus photoinhibition photoprotection chlorophyll fluorescence parameters PSⅡ reaction center

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Up-Regulated Expression of SOD2 and HPRT1 Following Topical photoprotection and Photorepair Skincare Formulations in A 3-Dimensional Reconstructed Human Skin Model

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Journal of Cosmetics, Dermatological Sciences and Applications 2023年第4期13卷 322-332页

作者： Yohei Tanaka Richard Parker Amaryllis Aganahi Clinica Tanaka Plastic Reconstructive Surgery and Anti-Aging Center Matsumoto Nagano Japan RATIONALE Kyneton Victoria Australia

Photodamage continues to threaten human skin health despite worldwide sun awareness campaigns and the widespread use of sunscreens. To date, extensive research is lacking into the effects of sun avoidance and solar specific skincare regimens on gene expression changes and DNA repair activity. We have previously reported that photoprotection and photorepair formulations which minimize the harmful effects of ultraviolet, visible light and near-infrared radiation can provide photoprotection, anti-photoaging benefits and rejuvenating effects optically, clinically and genetically. To investigate gene expression changes, specifically antioxidant and DNA repair effects following the use of topical photoprotection and photorepair formulations (The Essential Six, RATIONALE, Victoria, Australia), we used epidermal keratinocytes and dermal fibroblasts derived from a 3-dimensional reconstructed human skin model, and assessed upregulation of SOD2 and HPRT1. Gene expression was assessed via the Genemarkers Standard Skin Panel and quantitative real-time PCR exploration. Tissues were inoculated with solar specific topical formulations, then collected after 24 hours following application of photoprotection formulations and 16 hours following photorepair formulations. The quantitative real-time PCR revealed that, in comparison to the control, the genes encoding SOD2 and HPRT1 have been significantly up-regulated following usage of the photoprotection formulations, 1.86, and 1.41, respectively. SOD2 and HPRT1 were up-regulated following use of the photorepair formulations, 2.15, and 1.28, respectively. We were able to substantiate that the photo protection and photorepair formulations upregulated genes involved in antioxidant and DNA repair mechanisms in a 3-dimensional reconstructed human skin model, suggesting a promising anti-photoaging skin regimen. .

关键词： Antioxidant Anti-Photoageing DNA Repair Gene Expression photoprotection Photorepair

Regulation of DHICA-mediated antioxidation by dopachrome tautomerase:Implication for skin photoprotection against UVA radiation

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Regulation of DHICA-mediated antioxidation by dopachrome tau...

A novel thylakoid protein,HIGH LIGHT SENSITIVITY1,interacts with LQY1 and involves in photoprotection of photosystem Ⅱ in Arabidopsis thaliana

科技引领产业、支撑跨越发展——第六届湖北科技论坛

作者： Shan Jiang Xiao-Ming Liu Xin Dai Qiong Zhou Tie-Chi Lei Friedrich Beermann Kazumasa Wakamatsu Shi-Zheng Xu Department of Dermatology Renmin Hospital of Wuhan University Swiss Institute for Experimental Cancer Research School of Life ScienceEcole Polytechnique Federale de LausanneLausanneSwitzerland Fujita Health University School of Health Sciences Toyoake Aichi 470-1192Japan

Dopachrome tautomerase（Dct） is a critical enzyme in the melanogenesis pathway that isomerizes the intermediate dopachrome to 5,6-dihydroxyindole-2-carboxylic acid（DHICA） and influences the proportion of DHICA monomer incorporated into the 5,6-dihydroxyindole（DHI） polymer in *** investigate whether Dct inactivation affects skin photoprotection against ultraviolet radiation,we examined levels of reactive oxygen species（ROS）,sunburn cell formation,epidermal cell apoptosis,and melanin composition in skins of Dct knockout mice compared with skins of wild-type C57BL/6 mice under UVA-induced oxidative stress. The results demonstrate that Dct inactivation elevates the level of ROS,increases the numbers of sunburn cells and apoptotic cells,and decreases the amount of eumelanin in the epidermis upon exposure to chronic UVA radiation. Moreover,we determined the effects of DHICA-melanin,DHI-melanin,and a mixture of both on hydroxyl radical generation in the Fenton reaction utilizing an electron spin resonance ***-melanin exhibits a potent hydroxyl radical—scavenging activity,whereas DHI-melanin does ***,this study suggests that DHICA monomers are required to incorporate into the DHI polymer backbone of eumelanin,which highlights the important role of Dct in the regulation of DHICA-mediated antioxidation.

关键词： Dopachrome tautomerase Eumelanin Antioxidation photoprotection Reactive oxygen species Electron spin resonance Free radicals

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A novel thylakoid protein,HIGH LIGHT SENSITIVITY1,interacts ...