Oral Polypodium Leucotomos Extract and Its Impact on Visible Light-Induced Pigmentation in Human Subjects

BACKGROUND: Visible light (VL) has multiple effects on the skin that currently available sunscreens do not protect against. Polypodium leucotomos extract (PLE) has properties that may offer protection against VL. OBJECTIVES: To determine the effectiveness of PLE in preventing VL-induced effects. METHODS: Twenty-two subjects with Fitzpatrick skin phototype IV-VI were enrolled. On day 0, subjects were irradiated with VL. Clinical Investigator's Global Assessment (IGA) scoring and spectroscopic evaluations were performed immediately, 24 hours, and 7 days after irradiation. Subjects then received a 28-day supply of PLE (480 mg daily). Irradiation and evaluation were repeated. Three 4-mm punch biopsies were obtained for immunohistochemistry analysis: one from normal unirradiated skin and the other two twenty-four hours after irradiation, pre- and post-PLE, from sites irradiated with highest dose of VL. RESULTS: All subjects had immediate pigment darkening, persistent pigment darkening, and delayed tanning both pre- and post-PLE. For the highest VL dose (480 J/cm²) spectroscopic assessments demonstrated a statistically significant decrease in persistent pigment darkening and delayed tanning post-PLE. In addition, there was a significant decrease in cyclooxygenase-2, and a trend towards decreases in the markers for cellular damage post-PLE. While there was a trend towards lower IGA scores post-PLE, statistical significance was not reached possibly due to lack of sensitivity of the visual IGA scoring system in detecting small changes. CONCLUSIONS: Spectroscopic data and immunohistochemistry indicate an effect of PLE on visible light induced effects. As such, PLE may be used as an adjuvant to traditional means of photoprotection to protect against the effects of VL. Clinical trial registration number: NCT02904798. J Drugs Dermatol. 2019;18(12):1198-1203.

Update on the Management of Vitiligo

Vitiligo is an acquired, autoimmune disease characterized by depigmented macules and patches on the skin, which occur secondary to melanocyte destruction. Available therapeutic options are broadly divided into medical, surgical and phototherapy, though treatment of vitiligo can be challenging. Early diagnosis and management can maximize treatment efficacy. The purpose of this discussion is to review updates in the management of vitiligo, including existing and emerging therapies.

The potential role of antioxidants in mitigating skin hyperpigmentation resulting from ultraviolet and visible light-induced oxidative stress.

Oxidative stress is an integral element that influences a variety of biochemical reactions throughout the body and is known to play a notable role in melanogenesis. Exogenous triggers of oxidative stress, such as ultraviolet radiation (UVR) and visible light (VL), lead to pigment formation through somewhat different pathways, but both share a common endpoint-the potential to generate cosmetically undesirable hyperpigmentation. Though organic and inorganic sunscreens are available to protect against the UVR portion of the electromagnetic spectrum, coverage is lacking to protect against the VL spectrum. In this manuscript, we review the phases of tanning, pathways of melanogenesis triggered by UVR and VL, and the associated impact of oxidative stress. We also discuss the known intrinsic mechanisms and paracrine regulation of melanocytes that influence their response to UVR. Understanding these mechanisms and their role in UVR-induced hyperpigmentation should potentially lead to identification of useful targets that can be coupled with antioxidant therapy to alleviate this effect.

The impact of positive antinuclear antibody on narrowband ultraviolet B phototherapy in patients with vitiligo: A retrospective chart review.

BACKGROUND/PURPOSE: Screening antinuclear antibody (ANA) is not recommended prior to initiating narrowband ultraviolet B (NBUVB) phototherapy in vitiligo patients, unless concern for photosensitivity exists. Guidelines on prescribing NBUVB phototherapy in vitiligo patients with positive ANA are unavailable, prompting this study to uncover trends. METHODS: This retrospective chart review investigated patients 12 years of age or older with a diagnosis of vitiligo between January 2015 and September 2017, positive serum ANA, and NBUVB phototherapy. Demographic information, vitiligo type, ANA titer/pattern, starting dose, peak dose without phototoxicity, phototherapy frequency, total number of phototoxic events and treatments, coexisting photosensitizing disorders, and concomitant photosensitizing medications were collected. RESULTS: Seven (two males, five females) of 1485 charts met inclusion criteria. One Caucasian, two African-Americans, one Asian, and three Hispanic/Latinos patients were represented. Six of seven patients had generalized vitiligo and one had focal vitiligo. ANA titer/patterns and phototherapy frequencies were evaluated. Peak doses of NBUVB without phototoxic event were available in six of seven patients: 274, 290, 532, 618, 700, and 734 mJ/cm2 . Total number of phototoxic events varied: 1 (n = 1), 2 (n = 1), 4 (n = 1), 6 (n = 2), or 8 (n = 1). Total NBUVB treatments ranged between 6 and 132. Coexisting photosensitizing disorders were not identified. One patient had phototoxic events in association with photosensitizing medications. CONCLUSION: With regard to phototoxicity, meaningful trends were not identified that may guide prescription of phototherapy in vitiligo patients with positive ANA, suggesting ANA may not be exclusionary criteria when prescribing NBUVB.

Recent Developments in the Diagnosis and Management of Photosensitive Disorders.

Photodermatoses occur in males and females of all races and ages. Onset can be variable in timing and influenced by genetic and environmental factors. Photodermatoses are broadly classified as immunologically mediated, chemical- and drug-induced, photoaggravated, and genetic (defective DNA repair or chromosomal instability) diseases. Advances in the field have led to improved recognition and treatment of many photodermatoses. The purpose of this focused review is to provide an update on the diagnosis and management of a variety of photodermatoses, both common and less common, with review of recent updates in the literature pertaining to their diagnosis and management.