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Indian Journal of Dermatology,... 2012Topical corticosteroids and sunscreens are extensively used formulations, both as over-the-counter products and as prescription medicines. Topical corticosteroids are... (Review)
Review
Topical corticosteroids and sunscreens are extensively used formulations, both as over-the-counter products and as prescription medicines. Topical corticosteroids are increasingly being recognized as causes of allergic contact dermatitis. Because of their anti-inflammatory property, contact allergy to these agents may be difficult to suspect and prove. With corticosteroid allergy, there are special issues in patch testing that need to be considered: Screening tests need to be done with budesonide and tixocortol pivalate, and delayed readings are essential to pick up all positive cases. Preventive advice needs to be tailored according to the structural and chemical peculiarities of a particular molecule. Sunscreen allergy is a significant part of cosmetic allergy; especially in cases of photoallergic reactions. Each passing decade is bringing forth new allergens in this class. In many countries, benzophenones have recently been replaced by octocrylene as the leading causes of contact dermatitis to sunscreens. This article provides a broad overview of corticosteroid and sunscreen allergy so that the readers are aware of these important emerging classes of allergens.
Topics: Administration, Cutaneous; Adrenal Cortex Hormones; Cross Reactions; Dermatitis, Allergic Contact; Humans; Patch Tests; Sunscreening Agents
PubMed: 22960810
DOI: 10.4103/0378-6323.100520 -
Acta Dermato-venereologica Jun 2021The use of sunscreens is recommended to limit the impact of sun exposure on the skin. The objective of this study was to examine the relationship between sunscreen sales...
The use of sunscreens is recommended to limit the impact of sun exposure on the skin. The objective of this study was to examine the relationship between sunscreen sales and melanoma in 4 different countries with diverse sunscreen regulations. Data from publicly avail-able databases were examined for Sweden, England, Australia, and the USA from 1999 to 2018. The association between incidence of melanoma and sunscreen sales was estimated using a generalized estimating equation, and modelling was used to predict melanoma cases. Incidence of melanoma was positively associated with sunscreen sales in England, Australia, and the USA, and negatively associated with sunscreen sales in Sweden. Growth rates in melanoma cases of 0.42%, 16.7%, 19.1% and 12.2% were predicted for Sweden, England, Australia, and the USA, respectively. The differences observed between England, Australia, and the USA, on the one hand, and Sweden, on the other hand, are consistent with the adoption of strong regulations requiring the use of ultraviolet A blocking agents in sunscreens.
Topics: Australia; England; Humans; Skin Neoplasms; Sunscreening Agents; Sweden; Ultraviolet Rays
PubMed: 33734423
DOI: 10.2340/00015555-3788 -
Applied and Environmental Microbiology Nov 2023Recent years have seen a lot of interest in mycosporine-like amino acids (MAAs) because of their alleged potential as a natural microbial sunscreen. Since chemical... (Review)
Review
Recent years have seen a lot of interest in mycosporine-like amino acids (MAAs) because of their alleged potential as a natural microbial sunscreen. Since chemical ultraviolet (UV) absorbers are unsafe for long-term usage, the demand for natural UV-absorbing substances has increased. In this situation, MAA is a strong contender for an eco-friendly UV protector. The capacity of MAAs to absorb light in the UV-A (320-400 nm) and UV-B (280-320 nm) range without generating free radicals is potentially relevant in photoprotection. The usage of MAAs for purposes other than photoprotection has now shifted in favor of medicinal applications. Aside from UV absorption, MAAs also have anti-oxidant, anti-inflammatory, wound-healing, anti-photoaging, cell proliferation stimulators, anti-cancer agents, and anti-adipogenic properties. Recently, MAAs application to combat SARS-CoV-2 infection was also investigated. In this review article, we highlight the biomedical applications of MAAs that go beyond photoprotection, which can help in utilizing the MAAs as promising bioactive compounds in both pharmaceutical and cosmetic applications.
Topics: Amino Acids; Ultraviolet Rays; Anti-Inflammatory Agents; Sunscreening Agents; Antioxidants
PubMed: 37843273
DOI: 10.1128/aem.00740-23 -
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 -
PloS One 2018Sunscreen users are often inadequately protected and become sunburned. This study aimed to investigate how much two consecutive sunscreen applications increased the...
Sunscreen users are often inadequately protected and become sunburned. This study aimed to investigate how much two consecutive sunscreen applications increased the quantity of sunscreen applied and decreased the skin area left without sunscreen (missed area) compared to a single application. Thirty-one healthy volunteers wearing swimwear were included and applied sunscreen two consecutive times in a laboratory environment. Participants had pictures taken in black light before and after each application. As sunscreens absorb black light, the darkness of the skin increased with increasing amounts of sunscreen applied. We conducted a standard curve establishing a link between change in picture darkness and quantity of sunscreen. The quantity of sunscreen at selected skin sites as well as the percentage of missed area was determined after each application. Participants had missed a median of 20% of their available body surface after a single application. After double application they had missed 9%. The decrease in missed areas was significant for the whole body surface and for each of the body regions separately. The median participant had applied between 13% and 100% more sunscreen at the selected skin sites after double application than after single application. We recommend double application, especially before intense sun exposure.
Topics: Adult; Color; Female; Humans; Male; Skin; Sunburn; Sunscreening Agents; Ultraviolet Rays; Young Adult
PubMed: 29590142
DOI: 10.1371/journal.pone.0193916 -
Journal of Nanobiotechnology Sep 2023Excessive and prolonged ultraviolet radiation (UVR) exposure causes photodamage, photoaging, and photocarcinogenesis in human skin. Therefore, safe and effective sun...
Excessive and prolonged ultraviolet radiation (UVR) exposure causes photodamage, photoaging, and photocarcinogenesis in human skin. Therefore, safe and effective sun protection is one of the most fundamental requirements. Living organisms tend to evolve various natural photoprotective mechanisms to avoid photodamage. Among them, melanin is the main functional component of the photoprotective system of human skin. Polydopamine (PDA) is synthesized as a mimic of natural melanin, however, its photoprotective efficiency and mechanism in protecting against skin damage and photoaging remain unclear. In this study, the novel sunscreen products based on melanin-inspired PDA nanoparticles (NPs) are rationally designed and prepared. We validate that PDA NPs sunscreen exhibits superior effects on photoprotection, which is achieved by the obstruction of epidermal hyperplasia, protection of the skin barrier, and resolution of inflammation. In addition, we find that PDA NPs are efficiently intake by keratinocytes, exhibiting robust ROS scavenging and DNA protection ability with minimal cytotoxicity. Intriguingly, PDA sunscreen has an influence on maintaining homeostasis of the dermis, displaying an anti-photoaging property. Taken together, the biocompatibility and full photoprotective properties of PDA sunscreen display superior performance to those of commercial sunscreen. This work provides new insights into the development of a melanin-mimicking material for sunscreens.
Topics: Humans; Sunscreening Agents; Ultraviolet Rays; Antioxidants; Melanins; Skin; Anti-Inflammatory Agents
PubMed: 37775761
DOI: 10.1186/s12951-023-02107-7 -
Marine Drugs Feb 2021Scytonemin is a promising UV-screen and antioxidant small molecule with commercial value in cosmetics and medicine. It is solely biosynthesized in some cyanobacteria.... (Review)
Review
Scytonemin is a promising UV-screen and antioxidant small molecule with commercial value in cosmetics and medicine. It is solely biosynthesized in some cyanobacteria. Recently, its biosynthesis mechanism has been elucidated in the model cyanobacterium PCC 73102. The direct precursors for scytonemin biosynthesis are tryptophan and -hydroxyphenylpyruvate, which are generated through the shikimate and aromatic amino acid biosynthesis pathway. More upstream substrates are the central carbon metabolism intermediates phosphoenolpyruvate and erythrose-4-phosphate. Thus, it is a long route to synthesize scytonemin from the fixed atmospheric CO in cyanobacteria. Metabolic engineering has risen as an important biotechnological means for achieving sustainable high-efficiency and high-yield target metabolites. In this review, we summarized the biochemical properties of this molecule, its biosynthetic gene clusters and transcriptional regulations, the associated carbon flux-driving progresses, and the host selection and biosynthetic strategies, with the aim to expand our understanding on engineering suitable cyanobacteria for cost-effective production of scytonemin in future practices.
Topics: Antioxidants; Biotechnology; Cyanobacteria; Humans; Indoles; Nostoc; Phenols; Pigments, Biological; Sunscreening Agents
PubMed: 33673485
DOI: 10.3390/md19030129 -
Marine Drugs Jun 2021In the last few decades, the thinning of the ozone layer due to increased atmospheric pollution has exacerbated the negative effects of excessive exposure to solar... (Review)
Review
In the last few decades, the thinning of the ozone layer due to increased atmospheric pollution has exacerbated the negative effects of excessive exposure to solar ultraviolet radiation (UVR), and skin cancer has become a major public health concern. In order to prevent skin damage, public health advice mainly focuses on the use of sunscreens, along with wearing protective clothing and avoiding sun exposure during peak hours. Sunscreens present on the market are topical formulations that contain a number of different synthetic, organic, and inorganic UVR filters with different absorbance profiles, which, when combined, provide broad UVR spectrum protection. However, increased evidence suggests that some of these compounds cause subtle damage to marine ecosystems. One alternative may be the use of natural products that are produced in a wide range of marine species and are mainly thought to act as a defense against UVR-mediated damage. However, their potential for human photoprotection is largely under-investigated. In this review, attention has been placed on the molecular strategies adopted by marine organisms to counteract UVR-induced negative effects and we provide a broad portrayal of the recent literature concerning marine-derived natural products having potential as natural sunscreens/photoprotectants for human skin. Their chemical structure, UVR absorption properties, and their pleiotropic role as bioactive molecules are discussed. Most studies strongly suggest that these natural products could be promising for use in biocompatible sunscreens and may represent an alternative eco-friendly approach to protect humans against UV-induced skin damage.
Topics: Animals; Aquatic Organisms; Biological Products; Humans; Skin Neoplasms; Sunscreening Agents
PubMed: 34209059
DOI: 10.3390/md19070379 -
Der Hautarzt; Zeitschrift Fur... Apr 2022The task of the first sunscreens was to prevent the development of sunburn and, following the spirit of the 1950/1960s, to not impair the tanning of the skin. The need... (Review)
Review
The task of the first sunscreens was to prevent the development of sunburn and, following the spirit of the 1950/1960s, to not impair the tanning of the skin. The need to quantify the protective performance soon arose. Originally with the help of natural-nowadays artificial-sunlight, a method was developed to determine a sun protection factor (SPF). It is formally defined as a ratio between minimum erythema-effective UV dose on sunscreen-protected skin and minimum erythema-effective UV dose on unprotected skin (ISO 24444:2019). Three observations question the suitability of the method. (1) Interlaboratory variability: Despite strict standardization, results of SPF determinations from different laboratories are subject to large variations. (2) Natural vs. artificial sunlight: The radiation spectrum of artificial sunlight differs from that of natural sunlight. SPFs determined with artificial sunlight (as depicted on all sunscreens currently on the market) are significantly too high compared to SPF determination with natural sunlight. (3) Erythema burden: When determining SPF, subjects are exposed to potentially harmful radiation. Against this background alternative methods-in vitro SPF, hybrid diffuse reflectance spectroscopy (HDRS) and in silico calculations-are presented. These have the potential to replace the current method. As an immediate measure, it is recommended to return to the comprehensible description of low, medium, high, and very high protection and in the future to take into account the spectrum of natural sunlight.
Topics: Erythema; Humans; Sun Protection Factor; Sunburn; Sunlight; Sunscreening Agents
PubMed: 35333933
DOI: 10.1007/s00105-022-04958-x -
The Journal of Physical Chemistry. A Nov 2022Solar exposure of avobenzone, one of the most widely used commercial UVA filters on the market, is known to cause significant degradation. This finding has fueled...
Solar exposure of avobenzone, one of the most widely used commercial UVA filters on the market, is known to cause significant degradation. This finding has fueled research into developing photostabilizer molecules. In an effort to provide insight into their stand-alone photoprotection properties, the excited state dynamics of the photostabilizer, 3-(3,4,5-trimethoxybenzylidene) pentane-2,4-dione (TMBP), and its phenolic derivative, 3-(4-hydroxy-3,5-dimethoxybenzylidene) pentane-2,4-dione (DMBP), were studied with ultrafast transient absorption spectroscopy. Solutions of TMPB and DMBP in ethanol and in an industry-standard emollient, as well as TMBP and DMBP deposited on synthetic skin mimic, were investigated. These experiments were allied with computational methods to aid interpretation of the experimental data. Upon photoexcitation, these photostabilizers repopulate the electronic ground state via nonradiative decay within a few picoseconds involving a twisted intramolecular charge transfer configuration in the excited state, followed by internal conversion and subsequent vibrational cooling in the ground state. This finding implies that, aside from acting as a photostabilizer to certain UV filters, TMBP and DMBP may offer additional photoprotection in a sunscreen formulation as a stand-alone UV filter. Finally, TMBP and DMBP could also find applications as molecular photon-to-heat converters.
Topics: Pentanes; Ultraviolet Rays; Sunscreening Agents
PubMed: 36323639
DOI: 10.1021/acs.jpca.2c05580