Light-emitting diodes downregulate cathelicidin, kallikrein and toll-like receptor 2 expressions in keratinocytes and rosacea-like mouse skin.

Cathelicidin (LL-37), Toll-like receptor 2 (TLR-2) and kallikreins (KLKs) are key inflammatory mediators in rosacea. Laser or light-based devices have been successfully used for rosacea. We investigated the effects of light-emitting diodes (LEDs) on LL-37, KLKs, TLR-2 and protease activity in cultured normal human epidermal keratinocytes (NHEKs) and rosacea-like mouse skin (RLMS). LL-37, KLK5, KLK7 and vitamin D receptor were induced by 1α, 25-dihydroxyvitamin D3 (VD3 ) and TLR-2 by Ad-CMV transfection in cultured NHEKs. NHEKs were subjected to LED irradiation at differing wavelengths (480-940 nm) and fluences (1-40 J/cm2 ). Inflammatory mediators were analysed with RT-PCR and real-time PCR and protease activity analysis and immunocytofluorescence staining were performed for NHEKs. Changes in RLMS induced by LL-37 peptide were evaluated with real-time PCR, immunohistochemical staining and enzyme-linked immunosorbent assay. In NHEKs, LED at 630 and 940 nm significantly attenuated LL37, KLK5 and TLR-2 mRNA expressions. Protease activity was significantly suppressed at 630, 850 and 940 nm. In the RLMS, LL-37, KLK5 and PAR-2 mRNA expressions significantly decreased at 24 and 48 hours after LED irradiation was performed three times at 630 and 940 nm. mCAMP and IL-8 protein levels and protease activity after LED irradiation were lower than those in RLMS control groups. LED at 630 and 940 nm downregulated TLR-2, KLK5 and LL-37 expressions and protease activity in NHEK and RLMS. Thus, LEDs may be promising for rosacea treatment. However, clinical trials are required for further study.

The Effect of Capsaicin on Neuroinflammatory Mediators of Rosacea.

BACKGROUND: Rosacea is a chronic inflammatory skin disease with a pathophysiological mechanism that remains unclear. Recently, dysregulation of the sensory nerve system has been implicated in the development of this condition. OBJECTIVE: This study aimed to investigate the effect of capsaicin on neuroinflammatory mediators in rosacea. In addition, this study aimed to evaluate the attenuating effects of capsazepine, a transient receptor potential vanilloid type 1 (TRPV1) antagonist. METHODS: We obtained skin tissue from both rosacea patients and normal individuals for an in vivo study. In addition, normal human epidermal keratinocytes (NHEKs) were cultured, and treated with capsaicin and capsazepine for an in vitro study. Quantitative changes in neuroinflammatory mediators were evaluated by semi-quantitative reverse transcription-polymerase chain reaction (PCR), real-time PCR, enzyme-linked immunosorbent assay, and immunofluorescence staining. RESULTS: The data showed the increase of TRPV1, TRPV4, cathelicidin (LL37) and tumor necrosis factor-α (TNF-α) in skin tissue by real-time PCR. In addition, the data showed that cathelicidin (LL37), kallikrein-5 (KLK-5), TNF-α, vascular endothelial growth factor (VEGF), interleukin (IL)-1α, IL-1ß, IL-8, and protease-activated receptor 2 (PAR2) increased in capsaicin-treated NHEKs. Capsazepine attenuated the expression of TRPV1 and other mediators, except for IL-8, in capsaicin-treated NHEKs. CONCLUSION: We confirmed that TRPV1, TRPV4, cathelicidin (LL37) and TNF-α are increased in rosacea skin, and that capsaicin is associated with increase of neuroinflammatory mediators such as LL37, KLK-5, TNF-α, VEGF, IL-1α, IL-1ß, IL-8, and PAR2. Modulators or inhibitors of neuroinflammatory mediators including TRPV1 could be potential therapeutic option in the treatment of patients with rosacea.

Citron Essential Oils Alleviate the Mediators Related to Rosacea Pathophysiology in Epidermal Keratinocytes.

BACKGROUND: Citron is well known for an abundance of antioxidative and anti-inflammatory ingredients such as vitamin C, polyphenol compounds, flavonoids, and limonoids. OBJECTIVE: In this study, we aimed to evaluate the effects of citron essential oils on rosacea mediators in activated keratinocytes in vitro. METHODS: Normal human epidermal keratinocytes (NHEKs) were stimulated with 1α, 25-dihydroxyvitamin D3 (VD3) and interleukin 33 (IL-33) with LL-37 to induce rosacea mediators such as kallikrein 5 (KLK5), cathelicidin, vascular endothelial growth factor (VEGF), and transient receptor potential vanilloid 1 (TRPV1). These mediators were analyzed by performing reverse-transcription polymerase chain reaction (PCR), quantitative real-time PCR, immunocytofluorescence and enzyme-linked immunosorbent assay after NHEKs were treated with citron seed and unripe citron essential oils. RESULTS: The messenger RNA (mRNA) and protein levels of KLK5 and LL-37 induced by VD3 were suppressed by citron seed and unripe citron essential oils. Furthermore, the mRNA and protein levels of VEGF and TRPV1 induced by IL-33 with LL-37 were also suppressed by citron essential oils. CONCLUSION: These results show that citron essential oils have suppressive effects on rosacea mediators in activated epidermal keratinocytes, which indicates that the citron essential oils may be valuable adjuvant therapeutic agents for rosacea.

The antifungal effect of light emitting diode on Malassezia yeasts.

BACKGROUND: Malassezia (M.) species are members of the normal part of the skin flora, but they might induce or be involved with various cutaneous diseases. Although the role of Malassezia in the pathogenesis of cutaneous diseases is not fully understood, recent studies have shown that decreased density of Malassezia led to improvement of these diseases. OBJECTIVE: To identify the antifungal effect of light emitting diode (LED) against Malassezia, its antifungal mechanisms and the impact on the keratinocytes. METHODS: LED with various wavelengths (370-630nm) on Malassezia furfur, Malassezia sympodialis and Malassezia globosa was irradiated according to dose and then the antifungal effects were thereafter assessed. After irradiating LED with 392.5±1nm of wavelength according to dose on Malassezia species, reactive oxygen species (ROS) and lipid hydroperoxide production assay were measured. In addition, cell viability and inflammatory cytokines (IL-1α, IL-1ß, TNF-α, TGF-ß, TLR-2 and COX-2) expressions in normal human epidermal keratinocytes (NHEKs) by LED irradiation were evaluated. RESULTS: The growth of Malassezia species was dose-dependently suppressed by both LED with 380±2 and 392.5±1nm wavelengths. The increases of intracellular and extracellular ROS by LED irradiation with 392.5±1nm wavelengths were significantly observed compared to control group. The cell viability and cytokines in NHEKs were not significantly affected by LED irradiation under 5J/cm(2)in vitro. CONCLUSION: LED irradiation with 380±2 and 392.5±1nm wavelengths proved to have antifungal effect against Malassezia species and no impact on NHEKs under 5J/cm(2). The findings suggest that LED might be an adjunctive therapeutic light tool against Malassezia yeasts related cutaneous diseases.

Molecular changes following topical photodynamic therapy using methyl aminolaevulinate in mouse skin.

BACKGROUND: Photodynamic therapy (PDT) with aminolevulinic acid (ALA) or methyl aminolaevulinate (MAL) has been shown to enhance treatment of photoaged skin. However, there is little information about the molecular changes involved in dermal matrix remodeling following MAL-PDT for photorejuvenation. OBJECTIVE: We sought to analyze the molecular changes of the epidermal and dermal matrix after MAL-PDT in mouse skin. METHODS: Serial biopsy specimens were obtained at baseline and at various times after treatments with MAL-PDT, MAL alone and LED alone. To evaluate the molecular changes in the epidermal and dermal matrix, primary cytokines such as interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta1 (TGF-beta1), matrix metalloproteinases (MMPs), procollagen type I and III were evaluated by reverse transcriptase polymerase chain reaction, Western blot analysis, and immunohistochemistry assays. RESULTS: Elevation of primary cytokines and MMPs occurred at early points in time after one treatment with MAL-PDT based on the levels of mRNA and protein. On the other hand, procollagen type I protein increased later after MAL-PDT treatment. CONCLUSIONS: MAL-PDT activates more quantifiable alterations in the molecules associated with epidermal and dermal remodeling compared to treatment with MAL or LED alone. MAL-PDT significantly induced the epidermal and dermal matrix molecules required for photorejuvenation.