Effects of sunscreen on skin cancer and photoaging

Green approach for the synthesis of zinc oxide nanoparticles and their enhanced sun protection factor in the presence of octocrylene

BACKGROUND/PURPOSE

This research project aims to create and test an eco-friendly method for producing zinc oxide nanoparticles (ZnO NPs) using herbal extracts. The goal is to study how these nanoparticles can boost the Sun Protection Factor (SPF) of sunscreens when used along with the synthetic UV filter octocrylene.

METHODS

To make the ZnO NPs extracts from green tea, Bhringraj, Licorice and Cinnamon were used. These nanoparticles were analyzed using transmission electron microscopy (TEM). Sunscreen compositions were formulated as oil in water emulsions with or without octocrylene incorporating the ZnO NPs. Stability tests were carried out to monitor pH levels, colour and viscosity over the eight weeks at 45°C. The Sun Protection Factor study was done in vitro using a UV spectrophotometer.

RESULTS

The results showed that formulations containing both ZnO NPs and octocrylene had SPF levels compared to using octocrylene or ZnO NPs alone. Around 1.4 to 1.65 times higher than octocrylene alone and 3.7 to 4.5 times higher than ZnO NPs alone. The stability study demonstrated changes in pH, viscosity and colour during storage. Conclusion: In conclusion eco-friendly production of ZnO NPs utilizing herbal extracts presents a sustainable alternative to traditional methods. When combined with octocrylene these nanoparticles significantly enhance the SPF of products.

CONCLUSION

In conclusion eco-friendly production of ZnO NPs utilizing herbal extracts presents a sustainable alternative to traditional methods. When combined with octocrylene these nanoparticles significantly enhance the SPF of products.This study introduces an eco-friendly approach, to creating high SPF sunscreens focusing on sustainability and addressing safety and environmental issues in sun care products. The rising demand for sunscreens has triggered the exploration of innovative methods for producing zinc oxide nanoparticles (ZnO NPs) that go beyond traditional chemical processes. The research exhibits a synthesis method for ZnO NPs using herbal extracts from green tea leaves, Bhringraj leaves, Liquorice roots and Cinnamon bark avoiding the use of harmful precursors. The results display dispersed ZnO NPs with an average size of 100 nm. Furthermore, the study investigates how these green synthesized ZnO NPs interact with the synthetic UV filter octocrylene to potentially enhance SPF in sunscreen formulations. By combining these components, the study shows an increase in SPF compared to using them individually.This study adds to the knowledge of how green synthesized ZnO NPs enhance efficacy of sunscreen products. This study also introduces an innovative approach, for creating eco-friendly effective sunscreens that could revolutionize sun protection methods.

A review of sunscreen in the prevention of skin cancer

ObjectiveDespite the reported benefits of sunscreen use in preventing skin cancer, the overall protection from melanoma and non-melanoma skin cancers putatively reflects the frequency of use and sunscreen type. Herein, we review the current knowledge regarding sunscreen's effectiveness at averting the development of skin cancers.Data sourcesWe conducted an extensive PubMed search comprising several review articles on the topic of sunscreen use and prevention of skin cancer, with specific terms that included sunscreen and usage, skin cancer, and sunscreen side effects.Data summarySeveral observational, cohort studies and randomized controlled trials have underscored the benefits of sunscreen in forestalling skin cancers. In particular, the incidence of melanoma and squamous-cell carcinoma is reduced, although the effect of sunscreen on basal-cell carcinoma is relatively less pronounced.ConclusionsThe implications from this study indicate that sunscreen reduces the incidence of melanoma and non-melanoma skin cancers although deriving the intended effect is contingent upon the type of sunscreen and adherence to the recommended guidelines. The primary side effects from sunscreen include dermal irritation and rash; and since there is some indication that UV filter-based sunscreens may harbor carcinogenic properties, clinicians should advise their patients on the type of sunscreen, not to mention the frequency of use.

Therapeutic effect of NEO400, perillyl alcohol conjugated to linoleic acid, in a mouse model of UV-induced skin damage

Excessive exposure to ultraviolet radiation (UVR) causes harmful effects on human skin. Pre-exposure application of sunscreen can be protective, but not after damage already has occurred. There is a need for agents that can be applied post-UVR exposure to repair the damage. We investigated a novel compound, NEO400, that appears to meet this medicinal need. NEO400 was created by conjugating linoleic acid to perillyl alcohol. UVR was repeatedly administered to the skin of mice over several weeks, where it caused the typical signs of UV damage, including scaling of the skin, DNA damage, and elevated levels of inflammatory cytokines. However, when NEO400 was applied immediately post-UVR, it triggered the appearance of markers for dermal stem cell proliferation, and no signs of skin damage emerged. Furthermore, when NEO400 was applied to skin that already had incurred significant damage, it accelerated skin healing. When applied individually, linoleic acid and perillyl alcohol were ineffective, indicating that they had to be conjugated in order to exert therapeutic efficacy. None of these skin-protective effects could be achieved with Aloe vera gel, a popular and widely used post-exposure remedy. Our study suggests that NEO400 holds potential as a regenerative treatment for excessively UVR-exposed skin.

Examining U.S. Adults Risk Perceptions and Skin Protection Behaviors Using the 2022 HINTS Database

Background

This study aims to provide a general overview of cancer risk perceptions and reported sunburns to prevent sunburn and reduce the long-term risk of developing skin cancer.

Methods

Data were obtained from the 2022 Health Information National Trends Survey 6 and analysis was carried out with SPSS. Descriptive statistics were conducted to explore sociodemographic characteristics, cancer risk perceptions, and behaviors surrounding sunburns in our sample. Associations between number of sunburns and sociodemographic variables were reported using multinomial regression analysis.

Results

When asked how confident patients felt about their ability to take good care of their own health, most respondents felt either very confident (44.0%) or completely confident (27.3%). When asked how often they experienced a sunburn in the past 12 months, 2.1% reported experiencing more than 6 sunburns, 30.3% reported having between 1-5 sunburns, and 67.6% reported experiencing no sunburns. Using multinomial regression analysis, statistically significant associations were reported between number of sunburns and age, gender, occupation status, marital status, education, Hispanic origin, race, and income level.

Conclusion

The results of our study reinforce the need for public health interventions that effectively disseminate information on skin cancer risk across ethnic minority groups, especially in underserved communities within the U.S.

Enhanced sun protection factor of octocrylene with green tea and bhringraj extracts

OBJECTIVES

The aim of this study of sun protection factor boosting effect sunscreen compositions with herbal extract and combination with octocrylene.

MATERIALS AND METHODS

The standardized herbal extracts procured and studied their sun protection Factors. Camellia Sinensis (Green tea) leaf Extract, Eclipta prostrata (bhringraj) leaf extract are selected for the development of the herbal sunscreen composition along with octocrylene as synthetic sunscreen. The developed sunscreen composition contains defined concentration of herbal extracts and octocrylene were evaluated for their different physicochemical properties and stability. Sun protection factor boosting effect of herbal extracts is studied combination with octocrylene.

RESULTS

Invitro SPF studied for herbal extract individually and combination with octocrylene. The results of Invitro SPF study revealed the presence of green tea extract and, Eclipta prostrata (bhringraj) leaf extract shows excellent sun protection factor (SPF) boosting value of sunscreen composition containing 5% concentration of herbal extract and octocrylene. The sunscreen formulation containing 5% herbal extracts are stable for 12 weeks in an oven (45 °C).

CONCLUSION

The findings of this in-vitro SPF study revealed a sun protection boosting capacity of green tea extract and bhringraj extract confirmed.

SUMMARY

The over exposure of human skin to Ultra-Violet Radiation (UVR) can trigger photodamage, UV burn, pigmentation, erythema, and enhance the chance of dermal carcinoma. UVR causes DNA damage, which leads to dermal cancer. Daily sunscreens protect the skin from the adverse effects of sun rays, especially UVB (290-320 nm) and UVA (320-400 nm). The ozone layer filters UVC (200-290 nm) radiation when it enters into atmosphere of the earth. UVB causes sunburn, photo damage and cause mutagenic changes in nucleic acids. UVA increases ROS (Reactive Oxygen Species) accumulation. ROS is responsible for cell repair which leads to carcinogenesis, and the cause of photodamage. Herbal extracts contain polyphenols, and flavonoids act as a natural sunscreen that will filter Ultra-Violet (UVB) light and contain antioxidant characteristics to modulate the photo-oxidative damage that results from UV-induced Reactive Oxygen Species production. The UVR protection of most herbal extracts are required to attain the higher UV protection in the sun care products. The approaches for preparing sun care products with higher Sun Protection Factor (SPF) possible through Oil in water formulation with herbal extract combinations of octocrylene. The developed sunscreen composition containing different concentration of herbal extracts were evaluated for their other physicochemical properties and stability. Invitro SPF was studied for Camellia Sinensis (Green tea) Leaf Extract and Eclipta prostrata (bhringraj) leaf extract individually and in combination with octocrylene. The results of the Invitro SPF study revealed the Camellia Sinensis (Green tea) Leaf Extract with octocrylene shows better Sun protection factor than Eclipta prostrata (bhringraj) leaf extract with octocrylene. The Sun Protection Factor (SPF) enhancement value of sunscreen compositions was compared to both sunscreen macroemulsion and nanoemulsion.

High Sensitivity Singlet Oxygen Luminescence Sensor Using Computational Spectroscopy and Solid-State Detector

This paper presents a technique for high sensitivity measurement of singlet oxygen luminescence generated during photodynamic therapy (PDT) and ultraviolet (UV) irradiation on skin. The high measurement sensitivity is achieved by using a computational spectroscopy (CS) approach that provides improved photon detection efficiency compared to spectral filtering methodology. A solid-state InGaAs photodiode is used as the CS detector, which significantly reduces system cost and improves robustness compared to photomultiplier tubes. The spectral resolution enables high-accuracy determination and subtraction of photosensitizer fluorescence baseline without the need for time-gating. This allows for high sensitivity detection of singlet oxygen luminescence emission generated by continuous wave light sources, such as solar simulator sources and those commonly used in PDT clinics. The value of the technology is demonstrated during in vivo and ex vivo experiments that show the correlation of measured singlet oxygen with PDT treatment efficacy and the illumination intensity on the skin. These results demonstrate the potential use of the technology as a dosimeter to guide PDT treatment and as an analytical tool supporting the development of improved sunscreen products for skin cancer prevention.

Sun protection use and habits in the LGBTQI+ community in Lebanon: A cross sectional study

BACKGROUND

Sun exposure is an extrinsic risk factor for skin aging, wrinkle formation, and the development of skin cancer, namely melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Sun protection measures have emerged as an important means of preventing these harmful effects. Studies have shown that sexual minority men have a greater prevalence of skin cancer than heterosexual men.

AIMS

There is limited research investigating the reasons behind this risk of skin cancer development. This is especially important because identifying preventable risk factors, like those pertaining to sun exposure behaviors, can be targeted in the fight against skin cancer and help establish screening tools and preventive interventions for the SGM community. This study focused on members of the SGM community and demonstrated their tendency not to use sun-protective measures, as well as their deficits in knowledge of skin cancer prevention.

MATERIALS AND METHODS

This study is a cross-sectional study that investigates sun protection practices and trends among adults in Lebanon's SGM community using a survey. It includes adults aged 18-80 that were recruited from the dermatology clinics at AUBMC as well as LGBTQ+ organizations Helm and SIDC.

RESULTS

A total of 129 participants took part in the study and completed the survey. Reasons for tanning varied among our participants: tanning to get a color (13.1%), tanning to get vitamin D (4.6%), tanning socially (6.9%), and tanning for mood elevation (0.8%). No significant association was found between sexual orientation and SPF use (p = 0.167). No significant association was found between sexual orientation and tanning frequency during summer (p-value: 0.231). Similarly, no significant association was noted between sexual orientation and tanning bed use (0.951). No significant association was noted between the type of job and SPF use (p = 0.601). Despite no significance between SPF use and the highest educational degree attained (p = 0.070), the tendency to use SPF increased with higher levels of education. Moreover, awareness of sun-induced skin cancer did not significantly affect SPF use (p = 0.067). However, a significant association was found between the information source for skin cancer and SPF use (p < 0.001) where participants receiving information from dermatologists displayed notably higher SPF use (72.2%), compared to those obtaining information from media (18.2%) or family and friends (5.3%).

DISCUSSION

Surveying the perception of the Lebanese SGM community towards sun damage and their adaptive practices to prevent it can help implement and gear a nation-wide campaign to spread proper awareness about this subject. Studying their behavioral tendencies for not using sunscreen can help overcome this contributing risk factor for skin cancers.

CONCLUSION

Future investigations have yet to identify confounding variables contributing to higher levels of skin cancers in this population.

Are in-market control systems for sunscreens adequate for consumer protection? A review of the legal framework regulating sun protection factor labels in Europe

Public health authorities and regulations in Europe protect the population against the damaging effects of excessive solar ultraviolet radiation through, among other means, monitoring marketed sunscreens and enforcing compliance with sun protection factor labelling requirements. In-market control processes are fundamental and complementary to other public health initiatives in a context of suboptimal sunscreen use in real-world settings. However, the laboratory testing method used for determining the sun protection factor of sunscreens is known to produce variability of results. The combination of an inherently variable testing method with the necessary rigidity of regulations generates volatility in the decision-making process followed by regulators during official in-market controls and exposes sunscreens to be susceptible to accidental mislabelling challenges. This leads to a paradoxical situation that may leave most sunscreens incorrectly labelled in the market and to a potential dilemma for authorities. The issue may get further amplified when non-official sources echo and broadcast uncontrolled messages about sunscreens to the public. Amending current regulation with a tolerance level to compare results that accommodates the variability of results from sun protection factor tests would ease decision-making, bring robustness to an uncertain legal landscape, make more efficient the efforts to convey consistent public health messages about the benefits of sunscreen use and better protect users. There are precedents of using tolerance levels for regulatory decision-making in other fields, and a review of the applicable legal landscape in Europe reveals that implementing it for sunscreens would only require one change to current cosmetics law.

Comparison between endocrine activity assessed using ToxCast/Tox21 database and human plasma concentration of sunscreen active ingredients/UV filters

Sunscreen products are composed of ultraviolet (UV) filters and formulated to reduce exposure to sunlight thereby lessening skin damage. Concerns have been raised regarding the toxicity and potential endocrine disrupting (ED) effects of UV filters. The ToxCast/Tox21 program, that is, CompTox, is a high-throughput in vitro screening database of chemicals that identify adverse outcome pathways, key events, and ED potential of chemicals. Using the ToxCast/Tox21 database, octisalate, homosalate, octocrylene, oxybenzone, octinoxate, and avobenzone, 6 commonly used organic UV filters, were found to have been evaluated. These UV filters showed low potency in these bioassays with most activity detected above the range of the cytotoxic burst. The pathways that were most affected were the cell cycle and the nuclear receptor pathways. Most activity was observed in liver and kidney-based bioassays. These organic filters and their metabolites showed relatively weak ED activity when tested in bioassays measuring estrogen receptor (ER), androgen receptor (AR), thyroid receptor, and steroidogenesis activity. Except for oxybenzone, all activity in the endocrine assays occurred at concentrations greater than the cytotoxic burst. Moreover, except for oxybenzone, plasma concentrations (Cmax) measured in humans were at least 100× lower than bioactive (AC50/ACC) concentrations that produced a response in ToxCast/Tox21 assays. These data are consistent with in vivo animal/human studies showing weak or negligible endocrine activity. In sum, when considered as part of a weight-of-evidence assessment and compared with measured plasma concentrations, the results show these organic UV filters have low intrinsic biological activity and risk of toxicity including endocrine disruption in humans.

[Skin aging exposome]

The skin is a barrier organ and thus exposed to environmental factors from birth, which essentially determine skin aging. In order to describe and understand this complex process exactly, we applied the concept of the "exposome" to the environmentally induced skin aging process. In this review, we summarize current knowledge on the skin aging exposome. In this context, we characterize the most important exposomal factors, address their relative importance for skin aging and also the relevance of their mutual interactions. Finally, we discuss the clinical consequences resulting from this concept for an effective prevention of skin aging.

Characteristics of choice and satisfaction regarding the use of ultraviolet blockers in the golf population in Republic of Korea: A quantitative study

Background and Aims

Korea's golf population surpassed 5 million (5.15 million) as of 2020 according to data analyzed by Shinhan Financial Investment in 2021. Due to the continuous increase in the golf population, it is necessary to study the use of specific sunscreens. Men and women are using sunscreen selective attributes based on the actual use and perception of sunscreens for life. A questionnaire survey was conducted for an analysis of the effect of product satisfaction.

Methods

Statistical processing of materials collected by the data analysis method is analyzed using the Statistical Package for Social Science WIN 25.0 statistical package program through the process of data coding and data cleaning.

Results

This exercise was done under 3-4 h of strong ultraviolet (UV) rays, so products that have ensured the durability of UV protection are needed. Among the demographic characteristics of the golf population, gender, age, academic background, occupation, marriage status, and monthly income were investigated, and it was confirmed that the information path of a particular product was affected by the choice of purchase, increasing satisfaction and repurchase.

Conclusion

An analysis of the paper's survey showed that men's awareness and interest in sunscreens increased. It is expected that differentiated strategies will be needed for products that match the actual conditions and aptitudes of the effective golf population.

Solar Ultraviolet Radiation, Skin Cancer and Photoprotective Strategies in South Africa†

The most recent data relating to the incidence of, and mortality from, the three commonest forms of skin cancer, namely basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and cutaneous melanoma (CM), in the Black African, Colored, Asian/Indian and White population groups in South Africa are reviewed. While exposure to solar ultraviolet radiation is the major environmental risk factor for BCC in all four groups, for SSC in the White and Asian/Indian groups and for CM in the White group, this is unlikely to be the case for most SCCs in the Black African group and for most CMs in the Black African and Asian/Indian groups. Strategies for practical personal photoprotection in South Africa are discussed with particular emphasis on people at heightened risk of skin cancer including the White population group, those with HIV or oculocutaneous albinism and outdoor workers.

Applying sunscreen SPF 50 with high antioxidant capacity during fifteen days improves the dermis echogenicity and reduces the reddish skin undertone

BACKGROUND

Of the many effects induced by UV radiation on the skin, erythema is one of the most well-known features, which is a cutaneous inflammatory reaction correlated with acute photodamage. The utilization of sunscreen may reduce this process.

AIMS

To evaluate the utilization of a sunscreen SPF50 with high antioxidant capacity during 15 days by young men without photoprotection habits.

METHODS

For this, we evaluated erythema, skin hydration properties, and dermis echogenicity using skin imaging techniques. Forty male participants (aged between 18 and 28 years old), 36 without previous photoprotection habits, were recruited, and the erythema was evaluated using a visual score and skin colorimeter. Macroscopic images (VivaCam®) were also obtained. Dermis echogenicity was evaluated using high-frequency ultrasonography. All the participants received a sunscreen SPF 50 to use for 15 days.

RESULTS

The visual score presented a strong correlation (r = 0.8657) with the colorimeter results. Visually and using the biophysical methodologies was possible to observe the reduction of the visual erythema. The dermis echogenicity also improved, probably correlated with the acute inflammation reduction. No alterations were observed in the skin hydration and skin barrier parameters.

CONCLUSIONS

The utilization of complementary and correlated different skin biophysical and imaging techniques in this study allows a better comprehension regarding the skin early photoaging process due the direct sun exposure. The utilization with a SPF 50 sunscreen with high antioxidant potential allows for a reduction in the erythema after 15 days of usage, a quick result, however, did not improved the skin barrier or SC hydration.

Vitamin D and Sun Exposure: A Community Survey in Australia

Sun exposure carries both harms and benefits. Exposing the skin to the sun is the main modifiable cause of skin cancers, which exert a considerable health and economic burden in Australia. The most well-established benefit of exposure to ultraviolet (UV) radiation is vitamin D production. Australia has the highest incidence of skin cancer in the world but, despite the high ambient UV radiation, approximately one quarter of the population is estimated to be vitamin D deficient. Balancing the risks and benefits is challenging and requires effective communication. We sought to provide a snapshot of public knowledge and attitudes regarding sun exposure and vitamin D and to examine the associations between these factors and sun protective behaviors. In 2020 we administered an online survey; 4824 participants with self-reported fair or medium skin color were included in this analysis. Only 25% and 34% of participants were able to identify the amount of time outdoors needed to maintain adequate vitamin D status in summer and winter, respectively and 25% were concerned that sunscreen use inhibits vitamin D synthesis. This lack of knowledge was associated with suboptimal sun protection practices. Public education is warranted to prevent over-exposure, while supporting natural vitamin D production.

Antioxidants in Sunscreens: Which and What For?

Ultraviolet (UV) radiation promotes the generation of reactive oxygen species (ROS) and nitrogen species (RNS), resulting in skin damage. Cosmetic industries have adopted a strategy to incorporate antioxidants in sunscreen formulations to prevent or minimize UV-induced oxidative damage, boost photoprotection effectiveness, and mitigate skin photoaging. Many antioxidants are naturally derived, mainly from terrestrial plants; however, marine organisms have been increasingly explored as a source of new potent antioxidant molecules. This work aims to characterize the frequency of the use of antioxidants in commercial sunscreens. Photoprotective formulations currently marketed in parapharmacies and pharmacies were analyzed with respect to the composition described on the label. As a result, pure compounds with antioxidant activity were found. The majority of sunscreen formulations contained antioxidants, with vitamin E and its derivatives the most frequent. A more thorough analysis of these antioxidants is also provided, unveiling the top antioxidant ingredients found in sunscreens. A critical appraisal of the scientific evidence regarding their effectiveness is also performed. In conclusion, this work provides an up-to-date overview of the use of antioxidants in commercial sunscreens for a better understanding of the advantages associated with their use in photoprotective formulations.

Higher mycophenolate dosage is associated with an increased risk of squamous cell carcinoma in kidney transplant recipients

BACKGROUND

Kidney transplant recipients are at increased risk of keratinocyte cancers, namely squamous cell and basal cell carcinomas (SCCs and BCCs). This is primarily due to the high levels of immunosuppression that are required to prevent allograft rejection. Different immunosuppressive medications confer different risks, and the effect of mycophenolate mofetil on SCC and BCC risk is unclear. We explored the relationship between mycophenolate dose prescribed over the entire transplant period and the risk of SCC and BCC.

METHODS

Kidney transplant recipients from Queensland, Australia, were recruited between 2012 and 2014 and followed until mid-2016. During this time transplant recipients underwent regular skin examinations to diagnose incident SCCs and BCCs. Immunosuppressive medication regimens were obtained from hospital records, and the average mycophenolate dose/day over the entire transplantation period was calculated for each patient. Doses were divided into three ranked groups, and adjusted relative risks (RR_adj) of developing SCC and BCC tumours were calculated using negative binomial regression with the lowest dosage group as reference. Recipients who had used azathioprine previously were excluded; further sub-group analysis was performed for other immunosuppressant medications.

RESULTS

There were 134 kidney transplant recipients included in the study. The average age was 55, 31% were female and 69% were male. At the highest median mycophenolate dose of 1818 mg/day the SCC risk doubled (RR_adj 2.22, 95% CI 1.03-4.77) when compared to the reference group of 1038 mg/day. An increased risk persisted after accounting for ever-use of ciclosporin, ever-use of tacrolimus, and when excluding mammalian target of rapamycin users. This increased risk was mainly carried by kidney transplant recipients immunosuppressed for five or more years (RR_adj = 11.05 95% CI 2.50-48.81). In contrast, there was no significant association between BCC incidence and therapy with the highest compared with the lowest mycophenolate dosage (RR_adj = 1.27 95% CI 0.56-2.87).

CONCLUSION

Higher mycophenolate dosage is associated with increased SCCs in kidney transplant recipients, particularly those immunosuppressed for more than five years. The increased SCC risk persists after accounting for usage of other immunosuppressant medications.

The Damaging Effects of Long UVA (UVA1) Rays: A Major Challenge to Preserve Skin Health and Integrity

Within solar ultraviolet (UV) light, the longest UVA1 wavelengths, with significant and relatively constant levels all year round and large penetration properties, produce effects in all cutaneous layers. Their effects, mediated by numerous endogenous chromophores, primarily involve the generation of reactive oxygen species (ROS). The resulting oxidative stress is the major mode of action of UVA1, responsible for lipid peroxidation, protein carbonylation, DNA lesions and subsequent intracellular signaling cascades. These molecular changes lead to mutations, apoptosis, dermis remodeling, inflammatory reactions and abnormal immune responses. The altered biological functions contribute to clinical consequences such as hyperpigmentation, inflammation, photoimmunosuppression, sun allergies, photoaging and photocancers. Such harmful impacts have also been reported after the use of UVA1 phototherapy or tanning beds. Furthermore, other external aggressors, such as pollutants and visible light (Vis), were shown to induce independent, cumulative and synergistic effects with UVA1 rays. In this review, we synthetize the biological and clinical effects of UVA1 and the complementary effects of UVA1 with pollutants or Vis. The identified deleterious biological impact of UVA1 contributing to clinical consequences, combined with the predominance of UVA1 rays in solar UV radiation, constitute a solid rational for the need for a broad photoprotection, including UVA1 up to 400 nm.

Formulation of a new broad-spectrum UVB + UVA and blue light SPF50+ sunscreen containing Phenylene Bis-Diphenyltriazine (TriAsorB), an innovative sun filter with unique optical properties

Accumulating evidence from numerous comprehensive studies has demonstrated that blue light, in particular high-energy visible light, can exert a range of harmful effects on skin cells. These forms of radiation are now known to be able to trigger oxidation reactions, DNA damage, erythema and pigmentary changes, and may also be associated with photoaging. Sunscreens protecting the skin from only ultraviolet (UV)-B and UVA rays can therefore no longer be regarded as sufficient to help prevent skin damage from sunlight, and products containing filters that can provide broad-spectrum photoprotection are required. To meet this need, a new sunscreen formulation that provides photoprotection against solar radiation with wavelengths ranging from UV to visible light has been developed, using an innovative organic sun filter with unique optical properties: phenylene bis diphenyltriazine (TriAsorB™). This article outlines the development and characteristics of this innovative filter and describes new key results from studies performed to assess the effectiveness and safety of the filter and the new sunscreen product. The studies conducted so far demonstrate that the filter has a good human and environmental safety profile. In addition, the sunscreen, which contains TriAsorB in combination with three other UV filters to offer broad-spectrum sun protection with a high sun protection factor (SPF50⁺ ), appears to effectively prevent multiple forms of cellular photodamage, in particular blue light-induced oxidatively generated DNA lesions. Overall, the available data indicate that regular use of the TriAsorB-containing sunscreen could help prevent solar radiation-induced skin damage and the development of signs of premature skin aging, as well as photodermatoses caused or exacerbated by visible light.

The effect of on-site application density on the UV protection efficacy of sunscreens

BACKGROUND

Sun protection factor (SPF) and UVA protection factor (UVAPF) are performance indicators consumers recognize for UV protective cosmetics such as sunscreens. However, on-site application density affects actual UV protection, despite these indicators. To understand actual UV protection better, a more reliable manner is needed to verify application density for further discussion of photoprotection efficacy regarding public health.

OBJECTIVES

To estimate the UV protective efficacy of sunscreen in actual use based on the application density of UV protective cosmetics and the analysis of UV protective effect modulated by application density.

METHOD

The subjects applied the SPF-labeled sunscreens as usual. We measured the application amount and area including any amount on their hands to calculate the average application density on the face. Also, sunscreens were applied at densities of 0.5, 1.0, and 2.0 mg/cm² . The SPF values were measured at each application site to evaluate the effect of application density on photoprotection efficacy.

RESULT

We established a method of measuring application density utilizing three-dimensional photograph analysis. The median application density of the sunscreen applied in actual use was 1.33 mg/cm² . The measured SPF values decreased in association with the decreased application density of sunscreens. Based on the estimate assuming the first-order correlation, the SPF value required to get the protective effect equivalent to a sunscreen with SPF 15, 30, or 50 at 2 mg/cm² was calculated to be 23.8, 47.5, and 79.2, respectively, with the application density of 1.33 mg/cm² .

CONCLUSION

We demonstrated a reasonable procedure for estimating the photoprotection efficacy of sunscreens on the face. A suggestion was made to consider the application density for further discussion of photoprotection among consumers, especially for the long term with respect to public health.

An Exploration of the Use and Impact of Preventive Measures on Skin Cancer

Background: Skin cancer is the most common form of cancer, and both clinical and epidemiological data link cumulative solar dosages and the number of sunburns to skin cancer. Each year, more than 5.4 million new cases of skin cancer are diagnosed, incurring a significant health and financial burden. Recommended preventive measures for skin cancer include the use of sunscreen, sun avoidance, and protective clothing. This study used a national database to examine the association of preventive measures with the prevalence of skin cancer, specifically analyzing the preventive measures of sunscreen use, staying in the shade, and wearing long-sleeved shirts. The second aim was to determine which characteristics, if any, correlated with using prevention measures. Methods: This study analyzed data from the National Health and Nutritional Examination Survey 2015−2016 cycle to examine the association of three preventive measures (using sunscreen, staying in the shade, and wearing long-sleeved shirts) with skin cancer. Logistic regression and chi-square tests were utilized to examine the relationship between skin cancer and these prevention methods. Results: Sunscreen use (OR = 3.752; p < 0.05) was statistically associated with a lower prevalence of skin cancer, while wearing long-sleeved shirts (OR = 6.911; p = 0.064) and staying in the shade (OR = 0.646; p = 0.481) did not emerge as factors significantly associated with a lower prevalence after controlling for gender, race/ethnicity, marital status, income, health insurance, and general health. Additionally, men and individuals of color were less likely to use sunscreen. Conclusion: Sunscreen use was associated with a lower prevalence of skin cancer, while wearing long-sleeved shirts and staying in the shade was not significantly linked to lower rates of skin cancer, suggesting that these measures may not be as effective as sunscreen for preventing skin cancer. Men and individuals of color were significantly less likely to use sunscreen. These findings can help guide future education efforts and research regarding skin cancer prevention and suggest the need to develop male-oriented programs to mitigate the gender disparity in employing sun-protection measures.

Phenylene Bis-Diphenyltriazine (TriAsorB), a new sunfilter protecting the skin against both UVB + UVA and blue light radiations

Sunlight induces actinic keratosis, skin cancers and photoaging. Photoprotection is thus a major issue in public health to prevent the harmful effects of solar ultraviolet (UV) radiations. Recent data have shown that the visible (VIS) and infrared (IR) radiations can lead to skin damage by oxidative stress, suggesting that a balanced protection across the entire spectrum of sunlight is necessary to prevent cutaneous alterations. In this context, we developed a new generation of sunfilter called Phenylene Bis-Diphenyltriazine or TriAsorB (CAS N°55514-22-2). The aim of the present study was to assess the photoprotective efficacy of TriAsorB from UV to IR light. Spectrophotometric assays were performed to measure absorption and reflectance of TriAsorB in the different spectral ranges of sunlight: UV, VIS including blue light or high energy visible (HEV) and IR. DNA damage was evaluated using reconstructed human epidermis (RHE): 8-hydroxy-2'-deoxyguanosine (8OHdG) in response to HEV exposure, pyrimidine dimers (CPDs) and (6-4) photoproducts following solar-simulated radiation (SSR). TriAsorB is a broad spectrum UVB + UVA filter including long UVA. Interestingly, it also absorbs VIS radiations, especially in the HEV region. These radiations are also reflected. Protection in the IR spectral range is weak. Furthermore, the sunfilter specifically protects the skin against the oxidative lesions 8OHdG induced by HEV and prevents SSR-induced DNA damage. Thus, TriAsorB is an innovative sunfilter that might be used in sun care products for skin photoprotection from UV to VIS radiations. Finally, it prevents sunlight genotoxicity and protected the skin against solar radiations, especially blue light.

Perils & pearls of purchasing sun protection over the internet: A google project

BACKGROUND/PURPOSE

Sunscreen use has been shown to reduce the incidence of skin cancers. Internet purchasing allows access to internationally sourced sunscreens, despite varying accepted active ingredients and regulations around the world.

AIMS/OBJECTIVES

To determine the compliance of international sunscreen products advertised on the internet with the current Australian sunscreen standard (AS/NZS 2604:2012).

MATERIALS AND METHODS

Six sunscreen-related search queries were executed on Google between January-November 2018. Qualitative analysis of the search results to determine compliance with the current Australian sunscreen standard (AS/NZS 2604:2012) was performed by collecting descriptive data, including listed active ingredients of each advertised product. These were compared against the AS/NZS 2604:2012 list of permitted active ingredients. The compliance status of each product, and reasons for non-compliance were annotated. A multiple regression contingency table test was performed to determine whether compliance was associated with the products' country of origin, and a post hoc analysis was performed to identify countries with significant differences in discrepancy in compliance rate.

RESULTS

Execution of the sunscreen-related search queries on Google generated 1350 results. Only 613 of the 1291 (47.5%) included products were compliant with the AS/NZS 2604:2012 permitted sunscreen active ingredients. 552 of 1291 products were non-compliant due to insufficient information advertised. Australia, India and South Korea had significantly lower than expected compliance rates.

CONCLUSIONS

Online marketing of sunscreen products from other countries has a significantly lower than expected compliance rate with the AS/NZS 2604:2012 permitted sunscreen active ingredients, with many lacking the disclosure of the active ingredients. Advertising regulations for online suppliers need to be tightened to ensure that online consumers purchasing sunscreen products can make informed decisions, as the international E-commerce market rapidly expands.

Daily photoprotection to prevent photoaging

BACKGROUND

Extrinsic skin aging or photoaging was previously thought to be almost exclusively due to solar ultraviolet (UV) radiation. However, recent literature has described other contributing factors and clarification is thus required as to what extent and what type of daily photoprotection is needed to mitigate extrinsic skin aging.

METHODS

We reviewed the existing scientific evidence on daily photoprotection, and specific requirements at the product level, to prevent extrinsic skin aging. We critically reviewed the existing evidence on potential ecological and toxicological risks which might be associated with daily photoprotection.

RESULTS

Evidence shows that broad protection against the entire solar range of UVB, UVA, UVA1, visible light, and short infrared (IRA) is required to prevent extrinsic aging. Other exposome factors, such as air pollution and smoking, also contribute to skin aging. Daily broad-spectrum sunscreen photoprotection should thus contain antioxidant ingredients for additional benefits against UV, IRA, and pollution-induced oxidative stress as well as anti-aging active ingredients to provide clinical benefits against skin aging signs, such as wrinkles and dark spots. Broad-spectrum sunscreen containing pigments, such as iron oxide, may be required for melasma prevention. There is no conclusive clinical evidence that daily sunscreen use is unsafe or that it compromises vitamin D synthesis.

CONCLUSION

Daily use of broad-spectrum sunscreen containing antioxidant and anti-aging active ingredients can effectively reduce extrinsic aging.

Sun Protective Clothing and Sun Avoidance: The Most Critical Components of Photoprotection in Patients With Melanoma

BACKGROUND

Ultraviolet radiation is the main modifiable risk factor for melanoma which can be reduced by avoiding excess sun exposure.

OBJECTIVE

We sought to explore (1) sun protective practices, (2) effectiveness of these sun protective practices, and (3) vitamin D supplementation in patients with melanoma.

METHODS

Using the National Health Interview Survey, the authors conducted a cross-sectional analysis to investigate sun protective behaviors and sunburns among adults with melanoma compared with those without skin cancer. We calculated adjusted odds ratio (aOR), 95% confidence interval (95% CI), and p-values using logistic regression.

RESULTS

Patients with melanoma reported increased use of sun avoidance, shade, sunscreen, long sleeves, and hats, but had similar sunburn rates compared with those without skin cancer. Only sun avoidance and long sleeves were associated with decreased odds of sunburn. Patients with melanoma also reported decreased vitamin D supplementation.

CONCLUSION

Although it is reassuring that patients with melanoma practice sun protective behaviors, this does not always translate into reduced sunburns. Physicians should emphasize the importance of photoprotection, especially sun avoidance and sun protective clothing, to reduce future melanoma risk.

Skin impacts from exposure to ultraviolet, visible, infrared, and artificial lights - a review

Social distancing is conducive to grow the impact of artificial light in the daily life of the worldwide population with reported consequences to the skin. Sunlight is also essential for human development, indeed, solar radiation is composed of different types of wavelengths, which generate different skin effects. It can be divided into ultraviolet (UV), infrared (IR), and visible. UV radiation (UVA and UVB) has cutaneous biological effects ranging from photoaging, immunosuppression to melanoma formation, through the production of reactive oxygen species (ROS), inflammation and elevation of the energy state of organic molecules, changing the DNA structure. IR radiation reaches deeper layers of the skin and is also related to the generation of ROS, photoaging and erythema while visible light is responsible for generating ROS, pigmentation, cytokine formation, and matrix metallopeptidases (MMPs). Furthermore, artificial light could be harmful to the skin, as it can generate ROS, hyperpigmentation, and stimulate photoaging. Currently, we briefly summarized the cutaneous biological effects of sunlight, as well as artificial light on skin and remarked the opportunity of the evolution of current photoprotective formulas through new strategies with broad spectrum protection.

Environmentally-Induced (Extrinsic) Skin Aging: Exposomal Factors and Underlying Mechanisms

As a barrier organ, the skin is an ideal model to study environmentally-induced (extrinsic) aging. In this review, we explain the development of extrinsic skin aging as a consequence of skin exposure to specific exposomal factors, their interaction with each other, and the modification of their effects on the skin by genetic factors. We also review the evidence that exposure to these exposomal factors causes extrinsic skin aging by mechanisms that critically involve the accumulation of macromolecular damage and the subsequent development of functionally altered and/or senescent fibroblasts in the dermal compartment of the skin.

In vivo sun protection factor and UVA protection factor determination using (hybrid) diffuse reflectance spectroscopy and a multi-lambda-LED light source

The sun protection factor (SPF) values are currently determined using an invasive procedure, in which the volunteers are irradiated with ultraviolet (UV) light. Non-invasive approaches based on hybrid diffuse reflectance spectroscopy (HDRS) have shown a good correlation with conventional SPF testing. Here, we present a novel compact and adjustable DRS test system. The in vivo measurements were performed using a multi-lambda-LED light source and an 84-channel imaging spectrograph with a fiber optic probe for detection. A transmission spectrum was calculated based on the reflectance measured with sunscreen and the reflectance measured without sunscreen. The preexposure in vitro spectrum was fitted to the in vivo spectrum. Each of the 11 test products was investigated on 10 volunteers. The SPF and UVA-PF values obtained by this new approach were compared with in vivo SPF results determined by certified test institutes. A correlation coefficient R² = 0.86 for SPF, and R² = 0.92 for UVA-PF were calculated. Having examined various approaches to apply the HDRS principle, the method we present was found to produce valid and reproducible results, suggesting that the multi-lambda-LED device is suitable for in-vivo SPF testing based on the HDRS principle as well as for in-vivo UVA-PF measurements.

[Sun-damaged skin (photoaging): what is new?]

Skin aging results from the interaction of genetic and nongenetic so-called exposomal, factors. Among the exposomal factors, chronic, life-long exposure to sunlight is of eminent importance for the development of skin aging characteristics. Importantly, photoaging of human skin is not only caused by ultraviolet (UV) B and A radiation, but is also the consequence of exposure to wavelengths beyond the UV spectrum. These include visible, i.e. blue light (400-440 nm) as well as the short part of infrared radiation, i.e. IRA (760-1200 nm). Here we summarize the scientific evidence supporting these conclusions and emphasize the resulting consequences for daily photoprotection of human skin. We also explain the clinical significance of the concept that is offered by the skin aging exposome, which e.g. takes into account the fact that sunlight interacts with other exposomal factors and that this interaction is important for photoaging of the skin.

SCAN! A pharmacy-based, sun safety feasibility study

OBJECTIVES

Skin cancer is the most common form of cancer, and individuals from the medically underserved Appalachian region are at elevated risks for cancer morbidity and mortality. Skin cancer can be prevented by decreasing ultraviolet light exposure (sunscreen sun protection factor 30, shade, clothing, sunglasses, hats) and can be caught at an early treatable stage through a routine skin examination. The Skin Cancer Awareness Now! (SCAN!) pilot project promoted skin cancer prevention and screening in community pharmacies, using a dynamic communication model. The objectives of the study were to understand (1) the feasibility of the SCAN! and (2) the preliminary impact of the SCAN!

METHODS

We conducted pre- and postintervention surveys of the SCAN!, a student pharmacist-led or pharmacy resident-led intervention in community pharmacies (n = 3).

RESULTS

Participants (n = 90) had a mean age of 43.8 (SD= 18.4) years, were predominantly white (92.1%), without a college degree (65.6%), and had an average family income in the range of $25,000-$49,999, with approximately 16% falling below the poverty level. To begin, the SCAN! scored highly in attention (mean = 5.8), liking (mean = 6.1), comprehension (mean = 6.7), and intentions to be sun safe (mean = 6.0). Most improved in their knowledge of the amount of sunscreen needed per application for sun safety (66%, P < 0.01) and of melanoma features from pre- and postintervention (39%, P < 0.01). A multivariate analysis of variance indicated that knowledge and intentions improved (all P's < 0.01). Interaction effects indicated that improvements in knowledge were greater for those in the rural pharmacy (P = 0.03), and improvements in perceived importance were greater for those in urban pharmacies (P = 0.01).

CONCLUSION

The SCAN! intervention was well received by the population. Our study provides evidence that community pharmacy is a novel venue for skin cancer prevention interventions, particularly for rural, medically underserved populations.

Emerging Strategies to Protect the Skin from Ultraviolet Rays Using Plant-Derived Materials

Sunlight contains a significant amount of ultraviolet (UV) ray, which leads to various effects on homeostasis in the body. Defense strategies to protect from UV rays have been extensively studied, as sunburn, photoaging, and photocarcinogenesis are caused by excessive UV exposure. The primary lines of defense against UV damage are melanin and trans-urocanic acid, which are distributed in the stratum corneum. UV rays that pass beyond these lines of defense can lead to oxidative damage. However, cells detect changes due to UV rays as early as possible and initiate cell signaling processes to prevent the occurrence of damage and repair the already occurred damage. Cosmetic and dermatology experts recommend using a sunscreen product to prevent UV-induced damage. A variety of strategies using antioxidants and anti-inflammatory agents have also been developed to complement the skin's defenses against UV rays. Researchers have examined the use of plant-derived materials to alleviate the occurrence of skin aging, diseases, and cancer caused by UV rays. Furthermore, studies are also underway to determine how to promote melanin production to protect from UV-induced skin damage. This review provides discussion of the damage that occurs in the skin due to UV light and describes potential defense strategies using plant-derived materials. This review aims to assist researchers in understanding the current research in this area and to potentially plan future studies.

Synthesis and evaluation of 1,3,5-triazine derivatives as sunscreens useful to prevent skin cancer

The incidence of skin cancers such as non-melanoma skin cancer and malignant melanoma has increased in the last few years mainly because of chronic exposure to ultraviolet (UV) radiation. Sunscreens protect the skin against harmful UV radiations; however, some limitations of these products justify the discovery of new UV filters. Novel 1,3,5-triazine derivatives (12a-h) obtained by the optimization of prototype resveratrol were synthesized and characterized. All compounds exhibited sun protection factor (SPF) and UVA protection factor (UVAPF) in the range of 3-17 and 3-13, respectively. These values were superior to resveratrol and the UV filter ethylhexyl triazone (EHT) currently available on the market. In addition, all compounds demonstrated in vitro antioxidant activity and thermal stability with the decomposition at temperatures above 236 °C. In conclusion, the novel 1,3,5-triazine derivatives have emerged as new UV filters with antioxidant effect useful to prevent skin cancer.

Sunscreen photoprotection and vitamin D status

Background

Global concern about vitamin D deficiency has fuelled debates on photoprotection and the importance of solar exposure to meet vitamin D requirements.

Objectives

To review the published evidence to reach a consensus on the influence of photoprotection by sunscreens on vitamin D status, considering other relevant factors.

Methods

An international panel of 13 experts in endocrinology, dermatology, photobiology, epidemiology and biological anthropology reviewed the literature prior to a 1‐day meeting in June 2017, during which the evidence was discussed. Methods of assessment and determining factors of vitamin D status, and public health perspectives were examined and consequences of sun exposure and the effects of photoprotection were assessed.

Results

A serum level of ≥ 50 nmol L⁻¹ 25(OH)D is a target for all individuals. Broad‐spectrum sunscreens that prevent erythema are unlikely to compromise vitamin D status in healthy populations. Vitamin D screening should be restricted to those at risk of hypovitaminosis, such as patients with photosensitivity disorders, who require rigorous photoprotection. Screening and supplementation are advised for this group.

Conclusions

Sunscreen use for daily and recreational photoprotection does not compromise vitamin D synthesis, even when applied under optimal conditions.

What's already known about this topic?

Knowledge of the relationship between solar exposure behaviour, sunscreen use and vitamin D is important for public health but there is confusion about optimal vitamin D status and the safest way to achieve this.

Practical recommendations on the potential impact of daily and/or recreational sunscreens on vitamin D status are lacking for healthy people.

What does this study add?

Judicious use of daily broad‐spectrum sunscreens with high ultraviolet (UV) A protection will not compromise vitamin D status in healthy people.

However, photoprotection strategies for patients with photosensitivity disorders that include high sun‐protection factor sunscreens with high UVA protection, along with protective clothing and shade‐seeking behaviour are likely to compromise vitamin D status.

Screening for vitamin D status and supplementation are recommended in patients with photosensitivity disorders.

Linked Comment: https://doi.org/10.1111/bjd.18126.

https://doi.org/10.1111/bjd.18494 available online

Sunscreen Application, Safety, and Sun Protection: The Evidence

Recently in Canada, there has been an effort to create consistent messaging about sun safety as there is a lack of up-to-date evidence-based guidelines regarding sun-protection measures. This review aimed to provide updated, evidence-based recommendations on sunscreen application, safety, and sun protection regarding the following topics for which there is clinical uncertainty: physical barriers, sunscreen properties, sunscreen application, and risk-benefit analysis.

Challenges in assessing the sunscreen-melanoma association

Whether sunscreen use affects melanoma risk has been widely studied with contradictory results. To answer this question we performed a systematic review of all published studies, accounting for sources of heterogeneity and bias. We searched for original articles investigating the sunscreen-melanoma association in humans to February 28, 2018. We then used random-effects meta-analysis to combine estimates of the association, stratified by study design. Stratified meta-analysis and meta-regression were used to identify sources of heterogeneity. We included 21,069 melanoma cases from 28 studies published 1979-2018: 23 case-control (11 hospital-based, 12 population-based), 1 ecological, 3 cohort and 1 randomised controlled trial (RCT). There was marked heterogeneity across study designs and among case-control studies but adjustment for confounding by sun exposure, sunburns and phenotype systematically moved estimates toward decreased melanoma risk among sunscreen users. Ever- vs. never-use of sunscreen was inversely associated with melanoma in hospital-based case-control studies (adjusted odds ratio (OR) = 0.57, 95%confidence interval (CI) 0.37-0.87, pheterogeneity < 0.001), the ecological study (rate ratio = 0.48, 95%CI 0.35-0.66), and the RCT (hazard ratio (HR) = 0.49, 95%CI 0.24-1.01). It was not associated in population-based case-control studies (OR = 1.17, 95%CI 0.90-1.51, pheterogeneity < 0.001) and was positively associated in the cohort studies (HR = 1.27, 95%CI 1.07-1.51, pheterogeneity = 0.236). The association differed by latitude (pinteraction = 0.042), region (pinteraction = 0.008), adjustment for naevi/freckling (pinteraction = 0.035), and proportion of never-sunscreen-users (pinteraction = 0·012). Evidence from observational studies on sunscreen use and melanoma risk was weak and heterogeneous, consistent with the challenges of controlling for innate confounding by indication. The only RCT showed a protective effect of sunscreen.

Ameliorative effect of tranexamic acid on physiological skin aging and its sex difference in mice

An effective method to protect the skin from natural aging is unknown. Therefore, in this study, we examined the ameliorative effects of tranexamic acid on natural skin aging. In addition, we examined the sex difference in the effect exhibited by tranexamic acid. We bred hairless mice without ultraviolet ray irradiation and physical stress for 2 years. During the study period, mice were orally administered tranexamic acid (12 mg/kg/day) three times per week. Development of signs of skin aging was found to be ameliorated by tranexamic acid. Furthermore, synthetic inhibition of plasmin was observed following tranexamic acid treatment. The synthetic reinforcement of hyaluronic acid by an increase in the number of epidermal cells and the degradative inhibition of extracellular matrix (ECM) by matrix metalloproteinase (MMP) suppression were observed. These results indicate that natural skin aging was ameliorated by tranexamic acid via the regulation of the plasmin/TGF-β/epidermal cells/hyaluronic acid and plasmin/MMPs/ECM signal transmission pathways. Taken together, sex difference was observed for the ameliorative effect of tranexamic acid on skin aging, with a stronger effect observed in females than in males. More importantly, we found that the synthesis of hyaluronic acid was stronger in female mice than in male mice.

Mycosporine-Like Amino Acids for Skin Photoprotection

BACKGROUND

Excessive human exposure to solar ultraviolet radiation (UVR) continues to be a major public health concern, with skin cancer rates increasing year on year. The major protective measure is the use of synthetic UVR filters formulated into sunscreens, but there is a growing concern that some of these chemicals cause damage to delicate marine ecosystems. One alternative is the use of biocompatible mycosporine-like amino acids (MAA), which occur naturally in a wide range of marine species. Their role within nature is mainly thought to be photoprotective. However, their potential for human photoprotection is largely understudied.

OBJECTIVE

To review the role of MAA in nature and assess their potential as natural sunscreens for human skin photoprotection.

METHOD

A literature review of all relevant papers was conducted.

CONCLUSION

MAA are natural photostable compounds that are thought to offer photoprotection to marine species. Initially thought of as protective based on their absorption properties in the solar UVR spectrum, it is clear that MAA are multifunctional photoprotective compounds acting as chemical and biological anti-oxidants. This suggests that MAA may offer a novel eco-friendly approach to human skin photoprotection. Most studies have been carried out in vitro and current data strongly suggest that MAA have potential for development as natural biocompatible sunscreens that protect against a diverse range of solar UVR induced adverse effects on human health.

Awareness, behavior and attitudes concerning sun exposure among beachgoers in the northern coast of Peru

Background

Skin cancer incidence has increased over the last years, becoming a major public health problem.

Objective

To describe the awareness, behavior and attitudes concerning sun exposure among beachgoers in the northern coast of Peru.

Methods

We conducted a cross-sectional study in the Pimentel beach, Peru. The “Beach Questionnaire” was used and we surveyed all the beachgoers from 8 a.m. to 4 p.m. and from March 5 to March 19. For the statistical analysis, sun exposure habits, sunburns history, knowledge, attitudes and practices were crossed with sex using the chi2 test.

Results

We surveyed 410 beachgoers, the most frequent phototype was type III (40.5%). Only the 13.66% of the respondents correctly answered the seven knowledge questions related to sun exposure and skin cancer. Men more frequently agreed that “when they are tanned their clothes looks nicer” (p = 0.048). Likewise, regarding the questions “Sunbathing is relaxing” and “Sunbathing improves my mood”, men agreed or totally agreed with more frequency than women (63.64% vs. 46.15%, p < 0.001; and 61.36% vs 49.15%, p = 0.014, respectively). Regarding sun protection practices, women more frequently used sunshade (p = 0.001) and sunscreen (SPF ≥ 15) (p < 0.001) when compared to the male group.

Conclusion

Sun exposure is a potentially preventable risk factor for skin cancer. Thus, awareness of the risks of UVR overexposure and adequate sun-protective behaviors and attitudes are essential. Our results, however, are not as favorable as expected. Public health efforts should encourage sun-safety precautions and intervention campaigns should be carried out in recreational settings, such as the beaches.

Ginsenoside C-Mx Isolated from Notoginseng Stem-leaf Ginsenosides Attenuates Ultraviolet B-mediated Photoaging in Human Dermal Fibroblasts

Notoginseng is a traditional herbal medicine widely used for medicinal therapy in Asia, as it contains numerous ginsenosides with pharmacological effects. In this study, we submitted Notoginseng stem-leaf (NGL) ginsenosides to an enzyme to create a reaction with the monomer products of ginsenoside C-Mx and then investigated the ability of ginsenoside C-Mx to protect the skin against ultraviolet B-induced injury in normal human dermal fibroblasts (NHDFs). Ginsenoside C-Mx alleviated UVB-induced intracellular reactive oxygen species (ROS), MMP-1 and IL-6 expression while accelerating TGF-β and procollagen type I secretion. In addition, ginsenoside C-Mx reversed UVB-induced procollagen type I reduction by regulating the TGF-β/Smad signaling pathway. Moreover, ginsenoside C-Mx inhibited activation of AP-1 transcription factor, an inducer of MMPs. Ginsenoside C-Mx displayed an outstanding antioxidant capacity, increasing expression of cytoprotective antioxidants such as HO-1 and NQO-1 expression by enhancing the nuclear accumulation of Nrf2. Interestingly, application of ginsenoside C-Mx treatment (1, 10, 20 μm) significantly diminished UVB-induced suppressed NF-κB expression, decreasing the over-released inflammatory cytokines. Taken together, our findings indicated that ginsenoside C-Mx may act as a promising natural cosmetic ingredient for prevention and treatment of UVB-induced skin damage.

Molecular photoprotection of human keratinocytes in vitro by the naturally occurring mycosporine-like amino acid palythine

Background

Solar ultraviolet radiation (UVR) induces molecular and genetic changes in the skin, which result in skin cancer, photoageing and photosensitivity disorders. The use of sunscreens is advocated to prevent such photodamage; however, most formulations contain organic and inorganic UVR filters that are nonbiodegradable and can damage fragile marine ecosystems. Mycosporine‐like amino acids (MAAs) are natural UVR‐absorbing compounds that have evolved in marine species for protection against chronic UVR exposure in shallow‐water habitats.

Objectives

To determine if palythine, a photostable model MAA, could offer protection against a range of UVR‐induced damage biomarkers that are important in skin cancer and photoageing.

Methods

HaCaT human keratinocytes were used to assess the photoprotective potential of palythine using a number of end points including cell viability, DNA damage (nonspecific, cyclobutane pyrimidine dimers and oxidatively generated damage), gene expression changes (linked to inflammation, photoageing and oxidative stress) and oxidative stress. The antioxidant mechanism was investigated using chemical quenching and Nrf2 pathway activation assays.

Results

Palythine offered statistically significant protection (P < 0·005) against all end points tested even at extremely low concentrations (0·3% w/v). Additionally, palythine was found to be a potent antioxidant, reducing oxidatively generated stress, even when added after exposure.

Conclusions

Palythine is an extremely effective multifunctional photoprotective molecule in vitro that has potential to be developed as a natural and biocompatible alternative to currently approved UVR filters.

What's already known about this topic?

Mycosporine‐like amino acids (MAAs) are photoprotective molecules found in marine organisms but there are few data on their ability to protect skin cells from the adverse effects of solar ultraviolet radiation (UVR).

The European Chemicals Agency (ECHA) is concerned about the potential adverse health and ecotoxic effects of eight of 16 commonly used sunscreen filters in Europe. The Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme has expressed similar concerns.

What does this study add?

Palythine, an MAA extracted from an edible seaweed, affords photoprotection against a wide range of adverse effects in HaCaT keratinocytes exposed to solar simulating and ultraviolet A radiation. Of note is protection against two types of DNA photolesions; cyclobutane pyrimidine dimers and 8‐oxo‐7,8‐dihydroguanine.

Palythine is also a potent antioxidant that offers protection even when added after UVR exposure.

What is the translational message?

MAAs should be considered for development as natural biocompatible sunscreens that may address the concerns of the ECHA and EEAP.

Linked Comment: https://doi.org/10.1111/bjd.16598.

https://goo.gl/Uqv3dl

Patterns of Ultraviolet Radiation Exposure and Skin Cancer Risk: the E3N-SunExp Study

BACKGROUND

While ultraviolet (UV) radiation exposure is a recognized risk factor for skin cancer, associations are complex and few studies have allowed a direct comparison of exposure profiles associated with cutaneous melanoma, basal-cell carcinoma (BCC), and squamous-cell carcinoma (SCC) within a single population.

METHODS

We examined associations between UV exposures and skin cancer risk in a nested case-control study within E3N, a prospective cohort of 98,995 French women born in 1925-1950. In 2008, a lifetime UV exposure questionnaire was sent to all reported skin cancer cases and three controls per case, which were matched on age, county of birth, and education. Analyses were performed using conditional logistic regression and included 366 melanoma cases, 1,027 BCC cases, 165 SCC cases, and 3,647 controls.

RESULTS

A history of severe sunburns <25 years was associated with increased risks of all skin cancers (melanoma: OR 2.7; BCC: OR 1.7; SCC: OR 2.0 for ≥6 sunburns vs. none), while sunburns ≥25 years were associated with BCC and SCC only. While high-sun protection factor sunscreen use before age 25 was associated with lower BCC risk (Ptrend = 0.02), use since age 25 and reapplication of sunscreen were associated with higher risks of all three types of skin cancer. There were positive linear associations between total UV score and risks of BCC (Ptrend = 0.01) and SCC (Ptrend = 0.09), but not melanoma. While recreational UV score was strongly associated with BCC, total and residential UV scores were more strongly associated with SCC.

CONCLUSIONS

Melanoma, BCC, and SCC are associated with different sun exposure profiles in women.

Quantifying the visual appearance of sunscreens applied to the skin using indirect computer image colorimetry

BACKGROUND

There is no accepted method to objectively assess the visual appearance of sunscreens on the skin.

METHODS

We present a method for sunscreen application, digital photography, and computer analysis to quantify the appearance of the skin after sunscreen application. Four sunscreen lotions were applied randomly at densities of 0.5, 1.0, 1.5, and 2.0 mg/cm² to areas of the back of 29 subjects. Each application site had a matched contralateral control area. High-resolution standardized photographs including a color card were taken after sunscreen application. After color balance correction, CIE L*a*b* color values were extracted from paired sites. Differences in skin appearance attributed to sunscreen were represented by ΔE, which in turn was calculated from the linear Euclidean distance within the L*a*b* color space between the paired sites.

RESULTS

Sunscreen visibility as measured by median ΔE varied across different products and application densities and ranged between 1.2 and 12.1. The visibility of sunscreens varied according to product SPF, composition (organic vs inorganic), presence of tint, and baseline b* of skin (P < .05 for all).

CONCLUSION

Standardized sunscreen application followed by digital photography and indirect computer-based colorimetry represents a potential method to objectively quantify visibility of sunscreen on the skin.

Sunscreen Increasingly Overshadows Alternative Sun-Protection Strategies

The present study assessed perceptions of effective sun-protection strategies among the general public and whether these perceptions have changed in recent years. During five summers from 2007/2008 to 2011/2012, 4217 adolescents and adults living in a region with very high levels of solar UV radiation participated in annual, cross-sectional telephone surveys. Respondents' perceptions of the most effective sun-protection strategy were measured with a single open-ended question. In all survey years, sunscreen was the by far most frequently nominated sun-protection strategy, with an average mention rate of 71.0 %. The tendency to nominate sunscreen increased significantly over the 5-year study period and on average, was more common among adolescents compared to adults (81.6 vs 60.0 %) and females compared to males (73.6 vs 68.3 %). Despite respondents' increasing tendency to nominate sunscreen as the most effective sun-protection strategy, health experts have voiced concerns about flawed application practices. Current sun-protection hierarchies indicate that protective clothing and shade are better options.

Ultraviolet radiation accelerates NRas-mutant melanomagenesis: A cooperative effect blocked by sunscreen

To mitigate melanoma risk, sunscreen use is widely advocated; yet, the ability of sunscreens to prevent melanoma remains controversial. Here, we test the tenet that sunscreens limit melanoma risk by blocking ultraviolet radiation (UV)-induced DNA damage using murine models that recapitulate the genetics and spontaneous evolution of human melanoma. We find that a single, non-erythematous dose of UV dramatically accelerates melanoma onset and increases tumor multiplicity in mice carrying an endogenous, melanocyte-specific NRas^61R allele. By contrast, transient UV exposure does not alter tumor onset in mice lacking p16^INK4a or harboring an NRas^12D allele. To block the rapid onset of melanoma cooperatively caused by UV and NRas^61R , we employed a variety of aerosol sunscreens. While all sunscreens delayed melanoma formation and blocked UV-induced DNA damage, differences in aerosol output (i.e., amount applied/cm² ) caused variability in the cancer preventative efficacy of products with identical sunburn protection factor (SPF) ratings.

The Effect of Rhus verniciflua Stokes Extracts on Photo-Aged Mouse Skin

Background

Rhus verniciflua Stokes (RV) has traditionally been used in Korea as an indigenous food (Rhus chicken soup) and as an herbal medicinal plant. While the anticancer, antimicrobial, and anti-inflammatory properties of RV have been actively studied in the medical field, its antioxidant effects in the skin that resist the reactive oxygen species in keratinocytes and fibroblasts is less understood.

Objective

We designed to evaluate the effects of R. verniciflua Stokes extract (RVE) on the photo-aged skin by an in vitro experiment using human fibroblasts and an in vivo experiment using a photo-aged murine model.

Methods

For the in vitro experiments, human fibroblasts irradiated with ultraviolet (UV) B were treated with RVE or vehicle, and the growth levels and the expression level of type 1 procollagen were compared. For the in vivo experiment, photo-aged mice irradiated with UVB and UVA were administered drinking water with or without RVE, and histological changes and the expression level of type 1 procollagen and matrix metalloprotease (MMP)-13 were compared.

Results

In vitro experiments using fibroblasts irradiated with UVB showed that RVE promoted growth and significantly increased the expression of type 1 procollagen as compared to the control group. In the photo-aged mice, RVE increased collagen content in the dermis and promoted the synthesis of type 1 procollagen without any visible decrease in MMP-13 as compared to control group.

Conclusion

In addition to the previously reported antioxidant effects of RVE, oral intake of RVE effectively inhibited photo-aging in hairless mice by enhancing collagen synthesis.

Influence of demographic and clinical characteristics of actinic keratosis patients on illness perceptions and readiness to increase sun protection behaviours: an exploratory study

BACKGROUND/PURPOSE

There are no data comprehensively investigating the key beliefs and sun protection behaviours in patients with actinic keratosis (AK). Our aim was to determine and correlate the AK perceptions and readiness to increase sun protection (RISP) behaviours.

METHODS

AK patients' (n = 200) demographics and clinical findings were recorded. Participants completed questionnaires (Illness Perception Questionnaire-Revised and RISP behaviours scales).

RESULTS

The mean scores of giving up sunbathing of the patients aged <65 years, and giving up sunbathing and staying in the shade behaviours of females were higher. As the level of education increased, while the mean scores of giving up sunbathing decreased, using sunscreen scores increased. The mean scores of giving up sunbathing, using sunscreen and wearing protective clothing of those with the history of non-skin cancer (had cancer other than of the skin) were lower. The readiness to increase using sunscreen was found to be higher in patients with more chronic timeline beliefs, more positive perceived personal control and blaming sunlight more, and the wearing protective clothing was found to be higher in those with more cyclical timeline beliefs.

CONCLUSION

AK patients, especially the subjects aged ≥65 years, have non-skin cancer history, and male gender should be informed to apply sun-protective behaviours.