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Marine Drugs Sep 2015Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing... (Review)
Review
Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries.
Topics: Diatoms; Molecular Structure; Photosynthesis; Pigments, Biological
PubMed: 26389924
DOI: 10.3390/md13095847 -
Mini Reviews in Medicinal Chemistry Dec 2011Polyphenols are a large family of naturally occurring plant products and are widely distributed in plant foods, such as, fruits, vegetables, nuts, flowers, bark and... (Review)
Review
Polyphenols are a large family of naturally occurring plant products and are widely distributed in plant foods, such as, fruits, vegetables, nuts, flowers, bark and seeds, etc. These polyphenols contribute to the beneficial health effects of dietary products. Clinical and epidemiological studies suggest that exposure of the skin to environmental factors/pollutants, such as solar ultraviolet (UV) radiation induce harmful effects and leads to various skin diseases including the risk of melanoma and non-melanoma skin cancers. The incidence of non-melanoma skin cancer, comprising of squamous cell carcinoma and basal cell carcinoma, is a significant public health concern world-wide. Exposure of the skin to solar UV radiation results in inflammation, oxidative stress, DNA damage, dysregulation of cellular signaling pathways and immunosuppression thereby resulting in skin cancer. The regular intake of natural plant products, especially polyphenols, which are widely present in fruits, vegetables, dry legumes and beverages have gained considerable attention as protective agents against the adverse effects of UV radiation. In this article, we first discussed the impact of polyphenols on human health based on their structure-activity relationship and bioavailability. We then discussed in detail the photoprotective effects of some selected polyphenols on UV-induced skin inflammation, proliferation, immunosuppression, DNA damage and dysregulation of important cellular signaling pathways and their implications in skin cancer management. The selected polyphenols include: green tea polyphenols, pomegranate fruit extract, grape seed proanthocyanidins, resveratrol, silymarin, genistein and delphinidin. The new information on the mechanisms of action of these polyphenols supports their potential use in skin photoprotection and prevention of photocarcinogenesis in humans.
Topics: Animals; Anti-Inflammatory Agents; Anticarcinogenic Agents; DNA Repair; Humans; Polyphenols; Signal Transduction; Skin; Skin Neoplasms
PubMed: 22070679
DOI: 10.2174/13895575111091200 -
Clinical, Cosmetic and Investigational... 2023The COVID-19 pandemic may alter individuals' perspectives and behaviors regarding sun exposure and photoprotection. Presently, there is a paucity of information about...
BACKGROUND
The COVID-19 pandemic may alter individuals' perspectives and behaviors regarding sun exposure and photoprotection. Presently, there is a paucity of information about how the pandemic influences photoprotection in photodermatoses and melasma.
OBJECTIVE
To compare the photoprotection attitudes and behaviors of individuals with photodermatoses and melasma with those of a control group (other dermatologic patients) before and during the COVID-19 pandemic.
METHODS
A questionnaire-based, cross-sectional study was conducted among Thai patients with photodermatoses, melasma, and other dermatological conditions between August 2021 and November 2022. Each of the three groups consisted of 35 patients.
RESULTS
Among the 105 patients, 81.9% were female, and the mean age was 45.83 years. Over 80% of individuals who used surgical masks daily for 4 to 8 hours believed that these masks provided skin protection from the sun. The duration of sun exposure and the frequency of photoprotection practices decreased significantly in all groups during the COVID-19 pandemic compared to the pre-pandemic period. Sunscreen was the most prevalent form of photoprotection, but its usage declined considerably during the pandemic. Upon physical examination, the photodermatoses and control groups exhibited unchanged skin conditions, while the patients with melasma demonstrated improved skin conditions during the pandemic.
CONCLUSION
Owing to increased indoor activities and the perception that face masks could block sunlight, the COVID-19 pandemic led to notable reductions in sun exposure and photoprotective practices. Despite the absence of photodermatoses exacerbation and the observed improvements in patients with melasma, consistent and effective photoprotection must continue to be promoted.
PubMed: 37873511
DOI: 10.2147/CCID.S432108 -
Biochimica Et Biophysica Acta.... Oct 2017The melanocortin-1 receptor (MC1R) preferentially expressed in melanocytes is best known as a key regulator of the synthesis of epidermal melanin pigments. Its paracrine... (Review)
Review
The melanocortin-1 receptor (MC1R) preferentially expressed in melanocytes is best known as a key regulator of the synthesis of epidermal melanin pigments. Its paracrine stimulation by keratinocyte-derived melanocortins also activates DNA repair pathways and antioxidant defenses to build a complex, multifaceted photoprotective response. Many MC1R actions rely on cAMP-dependent activation of two transcription factors, MITF and PGC1α, but pleiotropic MC1R signaling also involves activation of mitogen-activated kinases and AKT. MC1R partners such as β-arrestins, PTEN and the E3 ubiquitin ligase MGRN1 differentially regulate these pathways. The MC1R gene is complex and polymorphic, with frequent variants associated with skin phenotypes and increased cancer risk. We review current knowledge of signaling from canonical MC1R, its splice isoforms and natural polymorphic variants. Recently discovered intracellular targets and partners are also discussed, to highlight the diversity of mechanisms that may contribute to normal and pathological variation of pigmentation and sensitivity to solar radiation-induced damage. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.
Topics: Animals; DNA Repair; Humans; Melanocytes; Melanoma; Polymorphism, Genetic; Protein Interaction Maps; Receptor, Melanocortin, Type 1; Signal Transduction
PubMed: 28259754
DOI: 10.1016/j.bbadis.2017.02.027 -
International Journal of Molecular... May 2024Melatonin is ubiquitously present in all animals and plants, where it exerts a variety of physiological activities thanks to its antioxidant properties and its key role... (Review)
Review
Melatonin is ubiquitously present in all animals and plants, where it exerts a variety of physiological activities thanks to its antioxidant properties and its key role as the first messenger of extracellular signaling functions. Most of the clinical studies on melatonin refer to its widespread oral use as a dietary supplement to improve sleep. A far smaller number of articles describe the clinical applications of topical melatonin to treat or prevent skin disorders by exploiting its antioxidant and anti-inflammatory activities. This review focuses on the clinical studies in which melatonin was applied on the skin as a photoprotective, anti-aging, or hair growth-promoting agent. The methodologies and results of such studies are discussed to provide an overall picture of the state of the art in this intriguing field of research. The clinical studies in which melatonin was applied on the skin before exposure to radiation (UV, sunlight, and high-energy beams) were all characterized by an appropriate design (randomized, double-blind, and placebo-controlled) and strongly support its clinical efficacy in preventing or reducing skin damage such as dermatitis, erythema, and sunburn. Most of the studies examined in this review do not provide a clear demonstration of the efficacy of topical melatonin as a skin anti-aging or as a hair growth-promoting agent owing to limitations in their design and/or to the use of melatonin combined with extra active ingredients, except for one trial that suggests a possible beneficial role of melatonin in treating some forms of alopecia in women. Further research efforts are required to reach definitive conclusions concerning the actual benefits of topical melatonin to counteract skin aging and hair loss.
Topics: Melatonin; Humans; Administration, Topical; Antioxidants; Animals; Skin Aging; Clinical Studies as Topic; Skin; Skin Diseases
PubMed: 38791203
DOI: 10.3390/ijms25105167 -
Molecules (Basel, Switzerland) May 2022Microalgae are complex photosynthetic organisms found in marine and freshwater environments that produce valuable metabolites. Microalgae-derived metabolites have gained... (Review)
Review
Microalgae are complex photosynthetic organisms found in marine and freshwater environments that produce valuable metabolites. Microalgae-derived metabolites have gained remarkable attention in different industrial biotechnological processes and pharmaceutical and cosmetic industries due to their multiple properties, including antioxidant, anti-aging, anti-cancer, phycoimmunomodulatory, anti-inflammatory, and antimicrobial activities. These properties are recognized as promising components for state-of-the-art cosmetics and cosmeceutical formulations. Efforts are being made to develop natural, non-toxic, and environmentally friendly products that replace synthetic products. This review summarizes some potential cosmeceutical applications of microalgae-derived biomolecules, their mechanisms of action, and extraction methods.
Topics: Anti-Inflammatory Agents; Antioxidants; Biological Products; Biotechnology; Cosmeceuticals; Cosmetics; Microalgae
PubMed: 35684447
DOI: 10.3390/molecules27113512 -
Frontiers in Pharmacology 2022Ethnopharmacological studies have become increasingly valuable in the development of botanical products and their bioactive phytochemicals as novel and effective... (Review)
Review
Ethnopharmacological studies have become increasingly valuable in the development of botanical products and their bioactive phytochemicals as novel and effective preventive and therapeutic strategies for various diseases including skin photoaging and photodamage-related skin problems including abnormal pigmentation and inflammation. Exploring the roles of phytochemicals in mitigating ultraviolet radiation (UVR)-induced skin damage is thus of importance to offer insights into medicinal and ethnopharmacological potential for development of novel and effective photoprotective agents. UVR plays a role in the skin premature aging (or photoaging) or impaired skin integrity and function through triggering various biological responses of skin cells including apoptosis, oxidative stress, DNA damage and inflammation. In addition, melanin produced by epidermal melanocytes play a protective role against UVR-induced skin damage and therefore hyperpigmentation mediated by UV irradiation could reflect a sign of defensive response of the skin to stress. However, alteration in melanin synthesis may be implicated in skin damage, particularly in individuals with fair skin. Oxidative stress induced by UVR contributes to the process of skin aging and inflammation through the activation of related signaling pathways such as the mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1), the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), the nuclear factor kappa B (NF-κB) and the signal transducer and activator of transcription (STAT) in epidermal keratinocytes and dermal fibroblasts. ROS formation induced by UVR also plays a role in regulation of melanogenesis in melanocytes modulating MAPK, PI3K/Akt and the melanocortin 1 receptor (MC1R)-microphthalmia-associated transcription factor (MITF) signaling cascades. Additionally, nuclear factor erythroid 2-related factor 2 (Nrf2)-regulated antioxidant defenses can affect the major signaling pathways involved in regulation of photoaging, inflammation associated with skin barrier dysfunction and melanogenesis. This review thus highlights the roles of phytochemicals potentially acting as Nrf2 inducers in improving photoaging, inflammation and hyperpigmentation regulation of cellular homeostasis involved in skin integrity and function. Taken together, understanding the role of phytochemicals targeting Nrf2 in photoprotection could provide an insight into potential development of natural products as a promising strategy to delay skin photoaging and improve skin conditions.
PubMed: 35645796
DOI: 10.3389/fphar.2022.823881 -
Journal of Travel Medicine 2013Although there have been recent advances in the development of photoprotective clothing and broad-spectrum sunscreens, few peer-reviewed publications have focused on... (Review)
Review
BACKGROUND
Although there have been recent advances in the development of photoprotective clothing and broad-spectrum sunscreens, few peer-reviewed publications have focused on photoprotection recommendations for travelers.
METHODS
In order to describe the adverse health effects of excessive ultraviolet (UV) radiation exposures; review recent studies of public perceptions regarding photoprotection and sun exposure behaviors; identify special populations at increased risks of drug-induced photosensitivity reactions and UV-induced skin cancers; and recommend several effective photoprotection strategies for travelers, Internet search engines were queried with the key words as search terms to examine the latest references on photoprotection and the epidemiology of UV-associated skin cancers.
RESULTS
Observational studies have demonstrated that the public knows little about proper sunscreen protection, selection, and use, and often abuses sunscreens for intentional UV overexposures. Cohort studies have identified special populations at increased risks of UV-associated skin cancers without the proper use of sunscreens and photoprotective clothing including children, fair-skinned persons, patients taking photosensitizing drugs, and organ transplant recipients (OTRs). Clinical investigations support the regular use of broad-spectrum sunscreens to prevent the development of premalignant actinic keratoses (AK) in all sun-exposed subjects, especially OTRs; to prevent the development of squamous cell carcinomas from new AK in sun-exposed subjects, especially OTRs; to possibly prevent the development of cutaneous malignant melanomas in children and adults; and to possibly prevent the development of basal cell carcinomas in OTRs.
CONCLUSIONS
Recommended photoprotection strategies for travelers should include avoiding intense sunlight, wearing photoprotective clothing, wearing sunglasses, and selecting the right sunscreen for their skin type. Travel medicine practitioners should counsel travelers about photoprotection and encourage travelers to take advantage of recent advances in the development of more effective broad-spectrum sunscreens and photoprotective clothing for themselves and their children.
Topics: Adult; Child; Environmental Exposure; Humans; Patient Education as Topic; Photosensitivity Disorders; Protective Agents; Protective Clothing; Risk Factors; Risk Reduction Behavior; Skin; Skin Neoplasms; Sunlight; Sunscreening Agents; Travel; Ultraviolet Rays
PubMed: 23464719
DOI: 10.1111/j.1708-8305.2012.00667.x -
Pharmaceutics Mar 2024The topical use of sunscreens is recommended for avoiding the damaging effects of UV radiation. However, improvements are still needed in the existing products to...
The topical use of sunscreens is recommended for avoiding the damaging effects of UV radiation. However, improvements are still needed in the existing products to enhance their photoprotection effectiveness and safety. This involves minimizing the use of chemical UV filters while providing enhanced and prolonged photoprotection. This work investigated novel sunscreen formulations and their UV protection effects by encapsulating Uvinul A, Tinosorb S, and Uvinul T150 into nanostructured lipid carriers (NLCs) based on bacuri butter and raspberry seed oil. First, the impact of critical formulation and process parameters on NLCs' particle size was evaluated using a 2 Face Centered Central Composite Design. Then, formulations were evaluated in terms of critical quality factors, in vitro skin permeation, and in vitro and in vivo photoprotection activities. The developed NLCs-containing formulations exhibited appropriate size (122-135 nm), PdI (<0.3), encapsulation efficiency (>90%), and drug content (>80%), which were preserved for at least 90 days under different stability conditions. Moreover, these NLCs-based formulations had equivalent skin permeation to emulsion-based controls, and the addition of NLCs into sunscreen cream bases in the optimum proportion of 20% (/) resulted in enhanced UVA and UVB photoprotection levels, despite a 10% reduction in the total filters content. Altogether, these results describe the application of nanoencapsulated organic UV filters in innovative sunscreen formulations to achieve superior photoprotection and cosmeceutical properties.
PubMed: 38543321
DOI: 10.3390/pharmaceutics16030427 -
Frontiers in Microbiology 2017Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water... (Review)
Review
Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water activity and cycles of desiccation in their hypersaline environments. Another feature common to their habitats is intense ultraviolet (UV) radiation, which is a challenge that microorganisms must overcome. The consequences of high UV exposure include DNA lesions arising directly from bond rearrangement of adjacent bipyrimidines, or indirectly from oxidative damage, which may ultimately result in mutation and cell death. As such, these microorganisms have evolved a number of strategies to navigate the threat of DNA damage, which we differentiate into two categories: DNA repair and photoprotection. Photoprotection encompasses damage avoidance strategies that serve as a "first line of defense," and in halophilic archaea include pigmentation by carotenoids, mechanisms of oxidative damage avoidance, polyploidy, and genomic signatures that make DNA less susceptible to photodamage. Photolesions that do arise are addressed by a number of DNA repair mechanisms that halophilic archaea efficiently utilize, which include photoreactivation, nucleotide excision repair, base excision repair, and homologous recombination. This review seeks to place DNA damage, repair, and photoprotection in the context of halophilic archaea and the solar radiation of their hypersaline environments. We also provide new insight into the breadth of strategies and how they may work together to produce remarkable UV-resistance for these microorganisms.
PubMed: 29033920
DOI: 10.3389/fmicb.2017.01882