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Photodermatology, Photoimmunology &... Nov 2020DNA damage is one of the main factors responsible for photoageing and is predominantly attributed to ultraviolet irradiation (UV-R). Photoprotection by conventional...
BACKGROUND
DNA damage is one of the main factors responsible for photoageing and is predominantly attributed to ultraviolet irradiation (UV-R). Photoprotection by conventional sunscreens is exclusively prophylactic, and of no value, once DNA damage has occurred. As a result, the demand for DNA repair mechanisms inhibiting, reversing or delaying the pathologic events in UV-exposed skin has sparked research on anti-photoageing and strategies to improve the effect of conventional sunscreens. This review provides an overview of recent developments in DNA repair enzymes used in sunscreens and their impact on photoageing.
METHODS
A systematic review of the literature, up to March 2019, was conducted using the electronic databases, PubMed and Web of Science. Quality assessment was carried out using the Newcastle-Ottawa scale (NOS) to ensure inclusion of adequate quality studies only (NOS > 5).
RESULTS
Out of the 352 publications, 52 were considered relevant to the key question and included in the present review. Two major enzymes were found to play a major role in DNA damage repair in sunscreens: photolyase and T4 endonuclease V. These enzymes are capable of identifying and removing UV-R-induced dimeric photoproducts. Clinical studies revealed that sunscreens with liposome-encapsulated types of photolyase and/or T4 endonuclease V can enhance these repair mechanisms.
CONCLUSION
There is a lack of randomized controlled trials demonstrating the efficacy of DNA repair enzymes on photoageing, or a superiority of sunscreens with DNA repair enzymes compared to conventional sunscreens. Further studies are mandatory to further reveal pathogenic factors of photoageing and possible therapeutic strategies against it.
Topics: Animals; DNA Damage; DNA Repair; Deoxyribodipyrimidine Photo-Lyase; Deoxyribonuclease (Pyrimidine Dimer); Humans; Skin Aging; Sunscreening Agents; Ultraviolet Rays; Viral Proteins
PubMed: 32772409
DOI: 10.1111/phpp.12597 -
Molecules (Basel, Switzerland) Jul 2020Sun overexposure is associated with the development of diseases that primarily affect the skin, which can lead to skin cancer. Among the main measures of photoprotection... (Meta-Analysis)
Meta-Analysis
Sun overexposure is associated with the development of diseases that primarily affect the skin, which can lead to skin cancer. Among the main measures of photoprotection is the use of sunscreens. However, there is currently concern about the reported harmful effects to both humans and the environment due to several of the sunscreen ingredients available on the market. For this reason, the search for and development of new agents with photoprotective properties is required. In searching for these metabolites, researchers have turned their attention to microbial sources, especially the microbiota in unusual hostile environments. Among the diverse microorganisms available in nature, Actinobacteria and specifically , have been shown to be a source of metabolites with various biological activities of interest, such as antimicrobial, antitumor and immunomodulator activities. Herein, we present the results of a systematic review of the literature in which isolates were studied as a source of compounds with photoprotective properties. A meta-analysis of the structure-property and structure-activity relationships of those metabolites identified in the qualitative analysis phase was also carried out. These findings indicate that are a source of metabolites with potential applications in the development of new, safe and more eco-friendly sunscreens.
Topics: Antioxidants; Biological Products; Humans; Secondary Metabolism; Streptomyces; Structure-Activity Relationship; Sunscreening Agents; Ultraviolet Rays
PubMed: 32679651
DOI: 10.3390/molecules25143221 -
JAMA Ophthalmology Jun 2019Cataract surgery, with intraocular lens (IOL) implantation, is the most common ocular surgical procedure worldwide. It has been suggested that IOLs that selectively...
IMPORTANCE
Cataract surgery, with intraocular lens (IOL) implantation, is the most common ocular surgical procedure worldwide. It has been suggested that IOLs that selectively attenuate short wavelength visible light (blue light-filtering IOLs) may be beneficial for macular health. Whether blue light-filtering IOLs impart retinal photoprotection is of public health relevance, particularly in the context of aging demographics and the increasing global prevalence of age-related macular degeneration. This review analyzes and interprets the key findings, including consideration of the implications for practice and future research, of a 2018 Cochrane systematic review that evaluated the efficacy and safety of blue light-filtering IOLs for providing protection to macular health and function.
OBSERVATIONS
The Cochrane systematic review included 51 randomized controlled trials that were performed in 17 countries. The trials involved adults undergoing cataract surgery in which a blue light-filtering IOL was compared with an equivalent non-blue light-filtering IOL. Study follow-up periods ranged from 1 month to 5 years. Together, these studies considered clinical outcomes in more than 5000 eyes. There was limited ability to combine data across trials (to draw overall conclusions) because of the use of different measurement techniques for outcomes, incomplete reporting of data, and/or varied follow-up periods. We identified substantial shortcomings in the internal validity of many of the included studies, particularly regarding trial design, conduct, and reporting. We propose several avenues for improving the rigor of potential future research in the field, including developing a core set of outcome measures, the inclusion of sample size calculations, the masking of trial participants and outcome assessors, and prospective clinical trial registration.
CONCLUSIONS AND RELEVANCE
Using blue light-filtering IOLs to impart benefits to the macula is currently not supported by the best available clinical research evidence, and it is important that clinicians are mindful of this evidence limitation when adopting these devices in clinical practice.
Topics: Cataract Extraction; Filtration; Humans; Lens Implantation, Intraocular; Lenses, Intraocular; Light; Prospective Studies; Radiation Injuries; Radiation Protection; Retina
PubMed: 30789642
DOI: 10.1001/jamaophthalmol.2019.0019 -
Frontiers in Bioengineering and... 2020Titanium dioxide nanoparticles (TiO NPs) are regularly used in sunscreens because of their photoprotective capacity. The advantage of using TiO on the nanometer scale is...
Titanium dioxide nanoparticles (TiO NPs) are regularly used in sunscreens because of their photoprotective capacity. The advantage of using TiO on the nanometer scale is due to its transparency and better UV blocking efficiency. Due to the greater surface area/volume ratio, NPs become more (bio)-reactive giving rise to concerns about their potential toxicity. To evaluate the irritation and corrosion of cosmetics, 3D skin models have been used as an alternative method to animal experimentation. However, it is not known if this model is appropriate to study skin irritation, corrosion and phototoxicity of nanomaterials such as TiO NPs. This systematic review (SR) proposed the following question: Can the toxicity of TiO nanoparticles be evaluated in a 3D skin model? This SR was conducted according to the Preliminary Report on Systematic Review and Meta-Analysis (PRISMA). The protocol was registered in CAMARADES and the ToxRTool evaluation was performed in order to increase the quality and transparency of this search. In this SR, 7 articles were selected, and it was concluded that the 3D skin model has shown to be promising to evaluate the toxicity of TiO NPs. However, most studies have used biological assays that have already been described as interfering with these NPs, demonstrating that misinterpretations can be obtained. This review will focus in the possible efforts that should be done in order to avoid interference of NPs with biological assays applied in 3D culture.
PubMed: 32587852
DOI: 10.3389/fbioe.2020.00575 -
JAMA Dermatology Sep 2019Microcystic adnexal carcinoma (MAC) occurs primarily in older adults of white race/ethnicity on sun-exposed skin of the head and neck. There are no formal guiding...
IMPORTANCE
Microcystic adnexal carcinoma (MAC) occurs primarily in older adults of white race/ethnicity on sun-exposed skin of the head and neck. There are no formal guiding principles based on expert review of the evidence to assist clinicians in providing the highest-quality care for patients.
OBJECTIVE
To develop recommendations for the care of adults with MAC.
EVIDENCE REVIEW
A systematic review of the literature (1990 to June 2018) was performed using MEDLINE, Embase, Web of Science, and the Cochrane Library. The keywords searched were microcystic adnexal carcinoma, sclerosing sweat gland carcinoma, sclerosing sweat duct carcinoma, syringomatous carcinoma, malignant syringoma, sweat gland carcinoma with syringomatous features, locally aggressive adnexal carcinoma, and combined adnexal tumor. A multidisciplinary expert committee critically evaluated the literature to create recommendations for clinical practice. Statistical analysis was used to estimate optimal surgical margins.
FINDINGS
In total, 55 studies met our inclusion criteria. The mean age of 1968 patients across the studies was 61.8 years; 54.1% were women. Recommendations were generated for diagnosis, treatment, and follow-up of MAC. There are 5 key findings of the expert committee based on the available evidence: (1) A suspect skin lesion requires a deep biopsy that includes subcutis. (2) MAC confined to the skin is best treated by surgery that examines the surrounding and deep edges of the tissue removed (Mohs micrographic surgery or complete circumferential peripheral and deep margin assessment). (3) Radiotherapy can be considered as an adjuvant for MAC at high risk for recurrence, surgically unresectable tumors, or patients who cannot have surgery for medical reasons. (4) Patients should be seen by a physician familiar with MAC every 6 to 12 months for the first 5 years after treatment. Patient education on photoprotection, periodic skin self-examination, postoperative healing, and the possible normal changes in local sensation (eg, initial hyperalgesia) should be considered. (5) There is limited evidence to guide the treatment of metastasis in MAC due to its rarity. Limitations of our findings are that the medical literature on MAC comprises only retrospective reviews and descriptions of individual patients and there are no controlled studies to guide management.
CONCLUSIONS AND RELEVANCE
The presented clinical practice guidelines provide an outline for the diagnosis and management of MAC. Future efforts using multi-institutional registries may improve our understanding of the natural history of the disease in patients with lymph node or nerve involvement, the role of radiotherapy, and the treatment of metastatic MAC with drug therapy.
PubMed: 31268498
DOI: 10.1001/jamadermatol.2019.1251