Updates on the Molecular Basis of Photoaging in All Skin Types.

Photoaging is a complex, ongoing process that clinically manifests as cutaneous rhytides, atrophy, laxity, dyspigmentation, telangiectasias, roughness, and mottled appearance of the skin. There is an abundance of research establishing the mechanism of ultraviolet (UV) - induced photodamage as it is a significant source of photoaging and skin cancers. While UV damage is known to induce photoaging, it is important to understand how other forms of light radiation also contribute to this process. UV only constitutes 5 to 10% of solar radiation that reaches the earth's surface. The remaining nearly 90% is evenly split between infrared and visible light radiation. Early research shows that varied skin types may elicit different photobiologic responses to light. This article presents the mechanisms and biomarkers of photodamage induced by light from across the spectrum, including UV, visible light, and infrared to better prevent and reverse the damage of photoaging in all skin types.J Drugs Dermatol. 2024;23(7):504-509.  doi:10.36849/JDD.7438.

Investigating the Relationship Between Acne and Vasodilatory Medications in a Hospital-Wide Adult Population.

Acne vulgaris is a common chronic dermatological condition characterized by obstruction and inflammation of pilosebaceous units. Recent research on a different dermatologic condition has demonstrated that the use of vasodilatory medications is associated with a decreased relative risk of rosacea. This finding is significant due to the overlapping inflammatory pathways involved in rosacea and acne. Herein, a retrospective cohort study was designed to determine the correlation between vasodilator usage and the risk of developing acne within 5 years, contrasting it with thiazide diuretics, chosen as a control due to its non-vasodilatory antihypertensive mechanism and availability of data. Angiotensin-converting enzyme (ACE) inhibitors (RR, 0.775; 95% CI, 0.727-0.826; P<0.05), angiotensin receptor blockers (ARBs) (RR, 0.739; 95% CI, 0.685-0.797; P<0.05), beta-blockers (BB) (RR, 0.829; 95% CI, 0.777-0.885; P<0.05), and calcium channel blockers (CCB) usage (RR, 0.821, 95% CI, 0.773-0.873; P<0.05) were associated with a significantly lower risk of developing acne within 5 years of initiating therapy compared to thiazide diuretics. It is unclear if thiazide diuretics are more likely to cause acne within the adult population or if vasodilators are protective against the development of acne. Finding mechanisms and therapeutics that lower the risk of developing acne is of significant public health interest, and this study provides a step toward this endeavor. Further research is required to uncover the underlying mechanisms for this reduction in the development of acne.  J Drugs Dermatol. 2024;23(6):446-449.     doi:10.36849/JDD.8362.

The Association Between Herpes Simplex Virus and Alzheimer's Disease: A Systematic Review.

Alzheimer's disease (AD) is a significant public health concern, affecting more than 6 million Americans; and currently, there are no cure or effective treatment options. The underlying etiology and pathogenesis are not fully understood, presenting a barrier to therapy. A substantial amount of data exists associating infection with Herpes simplex virus 1 (HSV-1) and AD. This review of published studies highlights the epidemiological associations between HSV-1 and AD. A systematic search of PubMed, Embase, and Web of Science was conducted on January 6, 2022, using PRISMA guidelines. Articles that presented epidemiological data correlating HSV-1 with AD were included. Bibliographies were screened for additional relevant articles as well. After review, 21 studies were included: 2 review articles and 19 population-based studies including case control, cohort, and cross-sectional studies.  The quantitative data derived from the studies in this report substantiate a relationship between infection with HSV-1 and AD. Based on these results, it may be of reasonable benefit to more consistently treat latent or active HSV-1 infection with anti-viral medications to potentially reduce the risk of AD. Furthermore, a prospective randomized controlled clinical trial could elucidate the benefit of anti-viral therapy to prevent or limit AD.J Drugs Dermatol. 2023;22(10):1046-1052     doi:10.36849/JDD.6785.

Visible light. Part I: Properties and cutaneous effects of visible light.

Approximately 50% of the sunlight reaching the Earth's surface is visible light (400-700 nm). Other sources of visible light include lasers, light-emitting diodes, and flash lamps. Photons from visible light are absorbed by photoreceptive chromophores (e.g., melanin, heme, and opsins), altering skin function by activating and imparting energy to chromophores. Additionally, visible light can penetrate the full thickness of the skin and induce pigmentation and erythema. Clinically, lasers and light devices are used to treat skin conditions by utilizing specific wavelengths and treatment parameters. Red and blue light from light-emitting diodes and intense pulsed light have been studied as antimicrobial and anti-inflammatory treatments for acne. Pulsed dye lasers are used to treat vascular lesions in adults and infants. Further research is necessary to determine the functional significance of visible light on skin health without confounding the influence of ultraviolet and infrared wavelengths.

Visible light. Part II: Photoprotection against visible and ultraviolet light.

Cutaneous photobiology studies have focused primarily on the ultraviolet portion of the solar spectrum. Visible light (VL), which comprises 50% of the electromagnetic radiation that reaches the Earth's surface and, as discussed in Part I of this CME, has cutaneous biologic effects, such as pigment darkening and erythema. Photoprotection against VL includes avoiding the sun, seeking shade, and using photoprotective clothing. The organic and inorganic ultraviolet filters used in sunscreens do not protect against VL, only tinted sunscreens do. In the United States, these filters are regulated by the Food and Drug Administration as an over-the-counter drug and are subject to more stringent regulations than in Europe, Asia, and Australia. There are no established guidelines regarding VL photoprotection. Alternative measures to confer VL photoprotection are being explored. These novel methods include topical, oral, and subcutaneous agents. Further development should focus on better protection in the ultraviolet A1 (340-400 nm) and VL ranges while enhancing the cosmesis of the final products.

The Vascular Component of Melasma: A Systematic Review of Laboratory, Diagnostic, and Therapeutic Evidence.

BACKGROUND: Melasma is a common acquired disorder of hyperpigmentation, classically manifesting as symmetric brown patches on the face. Although the exact pathogenesis is not fully understood, vascular abnormalities have been implicated in melasma. OBJECTIVE: To evaluate the laboratory and clinical evidence regarding the safety and efficacy of antivascular agents for the treatment of melasma. METHODS: A systematic review of PubMed, EMBASE, and Cochrane was conducted on May 13, 2020, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Original research articles investigating the role of vascularity and/or evaluating the use of antivascular therapeutics in melasma were included. Clinical recommendations were based on the American College of Physicians guidelines. RESULTS: A total of 34 original research articles as follows were identified: 4 laboratory studies, 15 diagnostic studies, and 15 therapeutic studies. CONCLUSION: There is promising evidence supporting the use of tranexamic acid and laser/light therapies to treat the vascular component of melasma, and more rigorous clinical trials are needed to validate their efficacy. Clinicians may consider treatment with one or more antivascular therapeutics in patients with melasma. Further research is warranted to characterize the role of cutaneous vascularization in melasma and may provide insights for novel therapies.

Topical Treatments for Melasma: A Systematic Review of Randomized Controlled Trials

Background: Melasma is an acquired skin disease characterized by symmetric hyperpigmentation on sun-exposed areas, particularly on the face. Recently, there has been tremendous scientific interest in novel, safe, and effective topical agents to manage melasma. Objective: To evaluate topical treatments for melasma and provide evidence-based recommendations for clinical use and further research. Methods: We performed a systematic review of randomized controlled trials (RCTs) on topical agents for the treatment of melasma on March 4th, 2019 using PRISMA guidelines. Clinical recommendations were based on the American College of Physicians guidelines. Results: After screening, we identified 35 original RCTs using azelaic acid, cysteamine, epidermal growth factor, hydroquinone (liposomal-delivered), lignin peroxidase, mulberry extract, niacinamide, Rumex occidentalis, triple combination therapy, tranexamic acid, 4-n-butylresorcinol, glycolic acid, kojic acid, aloe vera, ascorbic acid, dioic acid, ellagic acid and arbutin, flutamide, parsley, or zinc sulfate for melasma. Conclusions: Cysteamine, triple combination therapy, and tranexamic acid received strong clinical recommendations for the treatment of melasma. Cysteamine has excellent efficacy and is reported to have anti-cancer properties, but has not been directly compared with hydroquinone. Triple combination agents and tranexamic acid are effective, but carry theoretical risks for ochronosis and thrombosis, respectively. Natural compounds are associated with low risk for adverse events, but more research is needed to determine the efficacy, optimal formulation, and appropriate concentration of novel treatments. J Drugs Dermatol. 2019;18(11):1156-1171.

Electronic device generated light increases reactive oxygen species in human fibroblasts.

OBJECTIVES: Our skin is constantly exposed to light from solar radiation and electronic devices, which impact skin physiology and aging. The biological altering properties of ultraviolet (UV) solar radiation on skin have been well established. There is significant scientific and public interest on the effects of electronic device generated light (EDGL) on skin. Currently, the effects of EDGL on skin are largely unknown. EDGL includes UV, visible, and infrared light from consumer electronics such as smartphones, computers, and televisions. In this study, we measured the wavelength specific irradiance from electronic devices, and irradiated fibroblasts with white EDGL to determine changes in reactive oxygen species generation, apoptosis, and necrosis. METHODS: To determine the EDGL output of commonly used consumer electronic devices, we measured the irradiance from electronic devices at the manufacturers' recommended reading distances and at 1 cm. To determine the effect of EDGL on human skin cells, we irradiated AG13145 fibroblasts with EDGL for 1 hour at a distance of 1 cm and measured changes in reactive oxygen species generation, apoptosis, and necrosis. RESULTS: ROS increased significantly by 81.71%, 85.79%, and 92.98% relative to control following 1 hour of white EDGL from iPhone 8+, iPhone 6, and iPad (first generation), respectively. There was a non-significant change in apoptosis following irradiation with an iPhone 8+, iPhone 6, and iPad. Total necrosis was less than 2% for all treatment and control groups. CONCLUSIONS: Our results suggest that short exposures of EDGL increase ROS generation, but the long-term effects associated with repeated exposures of EDGL are unknown. As electronic devices become more widely used and integrated into society globally, we anticipate greater scientific research and general public interest on the effects of visible EDGL on skin. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc.

Light-emitting diodes in dermatology: A systematic review of randomized controlled trials.

OBJECTIVE: In dermatology, patient and physician adoption of light-emitting diode (LED) medical technology continues to grow as research indicates that LEDs may be used to treat skin conditions. The goal of this systematic review is to critically analyze published randomized controlled trials (RCTs) and provide evidence-based recommendations on the therapeutic uses of LEDs in dermatology based on published efficacy and safety data. METHODS: A systematic review of the published literature on the use of LED treatments for skin conditions was performed on September 13th 2017. RESULTS: Thirty-one original RCTs were suitable for review. CONCLUSIONS: LEDs represent an emerging modality to alter skin biology and change the paradigm of managing skin conditions. Acne vulgaris, herpes simplex and zoster, and acute wound healing received grade of recommendation B. Other skin conditions received grade of recommendation C or D. Limitations of some studies include small patient sample sizes (n < 20), absent blinding, no sham placebo, and varied treatment parameters. Due to few incidences of adverse events, affordability, and encouraging clinical results, we recommend that physicians use LEDs in clinical practice and researchers continue to explore the use of LEDs to treat skin conditions. Lasers Surg. Med. 9999:1-16, 2018. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

The Cellular Response of Keloids and Hypertrophic Scars to Botulinum Toxin A: A Comprehensive Literature Review.

BACKGROUND: Keloids and hypertrophic scars are conditions of pathologic scarring characterized by fibroblast hyperproliferation and excess collagen deposition. These conditions significantly impact patients by causing psychosocial, functional, and aesthetic distress. Current treatment modalities have limitations. Clinical evidence indicates that botulinum toxin A (BoNT-A) may prevent and treat keloids and hypertrophic scars. OBJECTIVE: To examine investigated cellular pathways involved in BoNT-A therapeutic modulation of keloids and hypertrophic scars. METHODS: The authors searched PubMed, Embase, and Web of Science for basic science articles related to botulinum toxin therapy, scarring, fibroblasts, keloids, and hypertrophic scars. RESULTS: Eleven basic science articles involving keloids and hypertrophic scars were reviewed. DISCUSSION: BoNT-A may reduce skin fibrosis by decreasing fibroblast proliferation, modulating the activity of transforming growth factor-ß, and reducing transcription and expression of profibrotic cytokines in keloid-derived and hypertrophic scar-derived dermal fibroblasts. BoNT-A may modulate collagen deposition, but there is a paucity of evidence regarding specific mechanisms of action. CONCLUSION: Overall, BoNT-A has the potential to prevent or treat pathologic scars in patients with a known personal or family history of keloids and hypertrophic scars, which may improve patient psychosocial distress and reduce clinic visits and health care costs. Variability in keloid and hypertrophic scar response to BoNT-A may be due to interexperiment differences in dosing, tissue donors, and assay sensitivity.

Thermal Ultra Short Photodynamic Therapy: Heating Fibroblasts During Sub-30-Minute Incubation of 5-Aminolevulinic Acid Increases Photodynamic Therapy-Induced Cell Death.

BACKGROUND: Actinic keratoses (AKs) prevalence was estimated at 39.5 million Americans in 2004, and the cost to treat AKs that year was approximately 1 billion dollars. Photodynamic therapy (PDT) is an FDA-approved therapy for the treatment of AK. Recent studies have focused on reducing PDT treatment time while maintaining efficacy. OBJECTIVE: To investigate the use of thermal modulation to improve the efficacy of ultra short aminolevulinic acid (ALA) incubation PDT. MATERIALS AND METHODS: Human dermal fibroblasts (HDFs) were incubated for 10, 15, or 20 minutes with 0.5-mM ALA at various temperatures (21, 24, 27, 30, 33, 36, 39, and 42°C). After ALA incubation, samples were treated for 1,000 seconds with blue light (417 ± 5 nm) resulting in a fluence of 10 J/cm. Samples were collected and stained for apoptosis/necrosis with annexin-V and 7-aminoactinomycin D (7-AAD), then analyzed by flow cytometry. RESULTS: Human dermal fibroblast treated with 10-minute ALA-PDT had no statistically significant changes in apoptosis at all temperatures. Human dermal fibroblast treated with 15- or 20-minute ALA-PDT had statistically significant increases in apoptosis at 39 and 42°C (p < .05). CONCLUSION: These results suggest the use of thermal modulation may improve ultra short ALA incubation PDT efficacy.

Combined Hyperthermic 1060nm Diode Laser Lipolysis With Topical Skin Tightening Treatment: Case Series.

BACKGROUND: As body contouring procedures have become more popular, post-procedural skin laxity is a concern. Non-invasive body contouring technologies may effectively reduce body fat, but modestly affect skin tightening. OBJECTIVE: To assess the efficacy and safety of a topical skin tightening agent in combination with hyperthermic diode laser lipolysis. METHODS: Herein, we describe five patients in which a skin tightening concentrate of 5% yeast extract, 2% hydrolyzed rice protein content, and 2.5% tripeptide was used after 1500-2100 J/cm2 of hyperthermic 1060 nm diode laser. RESULTS: Overall, all patients had a subjective positive response and high satisfaction with the combined treatment results of improvement in skin laxity and fat reduction. In all five cases, patients demonstrated visible fat reduction and skin improvement on photographs taken between weeks 6-18 compared to baseline. Blinded investigators correctly predicted the order of the photographs based on treatment results. No adverse events were reported. CONCLUSION: This case series demonstrated that a combined topical skin tightening concentrate with a hyperthermic laser lipolysis device may achieve improved aesthetic outcomes without adverse events. J Drugs Dermatol. 2018;17(7):780-785.

Psoriasiform Pemphigus Foliaceus in an African American Female: An Important Clinical Manifestation.

A 50-year-old African-American woman presented to the dermatology clinic with a pruritic eruption of 3 years' duration. On clinical examination, the patient had well-demarcated, pink, atrophic plaques and superficial erosions over the inframammary folds and mid-chest. She also had well-demarcated, hyperpigmented, hyperkeratotic scaly plaques over the abdomen, suprapubic region, elbows, knees, and back with sporadic small superficial blisters. A punch biopsy of the right abdomen was performed and revealed psoriasiform epidermal hyperplasia, focal parakeratosis, and acantholysis throughout the superficial spinous and granular layers. Only a sparse inflammatory infiltrate was present in the underlying dermis. Clinical and histological findings supported the diagnosis of pemphigus foliaceus (PF), but psoriasis was included in the differential diagnosis due to the presence of discrete plaques with an erythematous border. We hypothesize that patients with psoriasiform presentations of PF may be misdiagnosed with plaque psoriasis. It is important to distinguish between PF and psoriasis as there is evidence that ultraviolet light, a common treatment for psoriasis, may exacerbate PF. We document and highlight this atypical psoriasiform presentation of PF in a patient with skin of color to raise awareness and improve diagnosis and outcomes.

J Drugs Dermatol. 2018;17(4):471-473.

Efficacy of ultra short sub-30 minute incubation of 5-aminolevulinic acid photodynamic therapy in vitro.

BACKGROUND AND OBJECTIVE: The estimated incidence of cutaneous squamous cell carcinoma (SCC) is 700,000 cases per year. In the US, SCC incidence is highest among fair skinned adults older than 50 years of age. Thus, as the population ages, the reported number of SCCs will likely increase in the future. Photodynamic therapy (PDT) is an FDA approved therapy for treatment of actinic keratoses (AKs), a precursor to cutaneous SCC lesions. The FDA approved incubation time of the photosensitizing agent 5-aminolevulinic acid (ALA) is 14-18 hours. Recent studies have investigated short ALA incubation times of 1-3 hours with ALA and PDT demonstrating treatment success. Therefore, the question exists whether ALA incubation periods of less than 30 minutes are efficacious. Herein, we evaluate the efficacy of short ALA incubation periods by measuring apoptosis after 10, 15, and 20 minutes of ALA incubation. STUDY DESIGN/MATERIALS AND METHODS: AG13145 normal human dermal fibroblasts HDFs were incubated with 10, 15, or 20 minute of ALA at various concentrations (0, 0.05, 0.075, 0.1, 0.25, 0.375, 0.5, 1, and 2 mM). After ALA incubation, samples were treated with 1,000 seconds (16 minutes 40 seconds) of Blu-U fluorescent blue light (417 ± 5 nm) for a fluence of 10 J/cm2 . Immediately following treatment with blue light, samples were collected and stained for apoptosis and necrosis with annexin-V and 7-aminoactinomycin D (7-AAD), and then analyzed by flow cytometry. RESULTS: HDFs incubated with ALA for 10 minute at 36 °C followed by 10 J/cm2 of blue light had no statistically significant changes in apoptosis. HDFs incubated with ALA for 15 or 20 minutes at 36 °C followed by 10 J/cm2 of blue light had statistically significant increases in the percentages of cells positive for apoptosis in the 0.5, 1.0, and 2.0 mM ALA doses (P < 0.05). CONCLUSIONS: We found that incubation of ALA for at least 15 minutes followed by 10 J/cm2 of blue light resulted in a statistically significant increase in apoptosis. Lasers Surg. Med. 49:592-598, 2017. © 2017 Wiley Periodicals, Inc.

Blue light aminolevulinic acid photodynamic therapy downregulates cell division and proliferation pathways in cutaneous squamous cell carcinoma.

5-Aminolevulinic acid (5-ALA) photodynamic therapy (PDT) is a treatment for actinic keratosis (AK) and has been studied as a treatment for noninvasive cutaneous squamous cell carcinoma (cSCC). PDT induces apoptosis and necrosis in AKs and cSCC. 5-ALA blue light PDT may modulate gene expression and pathways in surviving cells. In this study, differential gene expression and pathway analysis of cSCC and human dermal fibroblasts were compared before and after 5-ALA blue light PDT using RNA sequencing. No genes were differentially expressed after correcting for multiple testing (false discovery rate < 0.05). As a result, transcription factor, gene enrichment, and pathway analysis were performed with genes identified before multiple testing (p < 0.05). Pathways associated with proliferation and carcinogenesis were downregulated. These findings using 5-ALA blue light PDT are similar to previously published studies using methyl-aminolevulinic and red light protocols, indicating that surviving residual cells may undergo changes consistent with a less aggressive cancerous phenotype.

Near-infrared light does not induce DNA damage in human dermal fibroblasts.

Photobiomodulation (PBM) can be used to treat a range of conditions in dermatology. PBM refers to the changes induced by red (RL, 620-700 nm) and near-infrared (NIR, 700-1440 nm) light. Light radiation-induced DNA damage is a major contributor to aging and skin cancer. It is crucial to study the effects of PBM on DNA to ensure safety. Our lab previously demonstrated that RL (633 ± 6 nm) did not result in human dermal fibroblasts (HDFs) DNA damage. This study employed similar methods to investigate NIR effects. Commercially available LED-NIR (830 ± 5 nm) panels (66, 132, and 264 J/cm2 ) did not result in DNA damage measured by cyclobutane pyrimidine dimers and pyrimidine-6,4-pyrimidone photoproducts in HDFs compared to temperature-matched controls immediately, 3 h, and 24 h following irradiation and compared to positive and negative controls. This demonstrates that LED-NIR does not damage DNA in HDFs in vitro.

Systematic review of randomized controlled trials of topicals for actinic keratosis field therapy.

Cutaneous field cancerization in dermatology describes the anatomic region of photodamaged skin with actinic keratoses (AKs) or cutaneous squamous cell carcinoma (cSCC) that is surrounded by cellular atypia, forming a dysplastic field. The concept of field cancerization is especially relevant in dermatology, as actinic keratoses and the surrounding dysplastic region can progress to carcinomas, necessitating the treatment of the field. Recent research has focused on field-directed therapy using topical agents. This study aims to systematically review randomized controlled trials on topical treatments for actinic keratosis field cancerization, following the PRISMA guidelines. Clinical recommendations were based on the Oxford Centre for Evidence-Based Medicine. We identified 20 original randomized controlled trials for topical cutaneous field therapy. 0.5% 5-Fluorouracil/salicylic acid and 0.5% 5-fluorouracil received a clinical recommendation grade of A, while diclofenac sodium received a clinical recommendation grade of B. Calcipotriol/5-fluorouracil, Imiquimod, sunscreen combination therapies, and tirbanibulin received a recommendation grade of C. This review provides a framework for clinicians when considering topical treatments for patients with field cancerization.

Systematic review of topical, laser, and oral treatments in acanthosis nigricans clinical trials.

Acanthosis nigricans (AN), with an estimated prevalence of 19.4% in the U.S., presents as hyperpigmented, velvety plaques in intertriginous regions. Acanthosis Nigricans negatively affects psychological well-being and particularly impacts skin of color individuals. Addressing the underlying cause of acanthosis nigricans, as current guidelines recommend, is often challenging. This highlights the importance of skin directed treatment for acanthosis nigricans. This systematic review evaluated topical, laser, and oral treatments for acanthosis nigricans and provides evidence-based recommendations for clinical use. Adhering to PRISMA guidelines, we evaluated 19 clinical trials investigating topical, oral, and laser interventions for acanthosis nigricans. Oxford Centre for Evidence-Based Medicine guidelines were used to make clinical recommendations. We strongly recommend topical tretinoin (grade A) and endorse the appropriate use of adapalene gel, urea cream, and fractional carbon dioxide laser therapy (grade B). Further research is essential to enhance our understanding of alternative treatments to determine additional evidence-based recommendations. This review aims to guide clinicians in managing acanthosis nigricans, especially when direct treatment of underlying conditions is impractical.