Identification of ultraviolet B radiation­induced microRNAs in normal human dermal papilla cells.

Ultraviolet (UV) radiation impairs intracellular functions by directly damaging DNA and by indirectly generating reactive oxygen species (ROS), which induce cell cycle arrest and apoptosis. UV radiation can also alter gene expression profiles, including those of mRNA and microRNA (miRNA). The effects of UV radiation on cellular functions and gene expression have been widely documented in human skin cells such as keratinocytes, melanocytes and dermal fibroblasts, but the effect it has on other types of skin cell such as dermal papilla cells, which are crucial in the induction of hair follicle growth, remains unknown. In the current study, the effect of UV radiation on physiological changes and miRNA-based expression profiles in normal human dermal papilla cells (nHDPs) was investigated. UVB radiation of ≥50 mJ/cm2 displayed high cytotoxicity and apoptosis in a dose-dependent manner. In addition, ROS generation was exhibited in UVB-irradiated nHDPs. Furthermore, using miRNA microarray analysis, it was demonstrated that the expression profiles of 42 miRNAs in UVB-irradiated nHDPs were significantly altered compared with those in the controls (35 upregulated and 7 downregulated). The biological functions of the differentially expressed miRNAs were studied with gene ontology analysis to identify their putative target mRNAs, and were demonstrated to be involved in cell survival- and death-related functions. Overall, the results of the present study provide evidence that miRNA­based cellular mechanisms may be involved in the UVB-induced cellular response in nHDPs.

The efficacy and safety of a proposed herbal moisturising cream for dry skin and itch relief: a randomised, double-blind, placebo-controlled trial--study protocol.

BACKGROUND: Moisturisers prevent and treat dry skin. They can also protect sensitive skin, improve skin tone and texture, and mask imperfections. Herbal medicines or their extracts have been available as topical formulations and cosmetics. Arctium lappa L. (Asteraceae) has been used to treat inflammatory disorders and various skin problems. It could be a candidate herbal medicine for treating dry skin condition.This study aims to establish the efficacy and safety of a proposed herbal moisturising cream containing Arctium lappa L. seed extract, which has been approved by the Korean Ministry of Food and Drug Safety for use in cosmetics. METHODS/DESIGNS: This study is a randomised, double-blind, placebo-controlled study with two parallel groups (proposed herbal moisturising cream vs. placebo cream). We will recruit 66 healthy male and female participants, aged 20 to 65 years, who have been diagnosed with dry skin conditions. Participants will be randomly allocated to receive either the proposed herbal moisturising cream or a placebo cream for four weeks. Each participant will be examined for signs and symptoms before and after using the cream. Skin hydration, sebum (oily secretion) levels and transepidermal water loss (TEWL; constitutive loss of water from the skin surface) will be assessed. Participants will also be asked to fill out a health-related quality of life questionnaire. Safety will be assessed using blood tests, urine analysis, a pregnancy test, and the assessment of vital signs. DISCUSSION: This trial will utilise high-quality methodologies in accordance with both consolidated standards for reporting trials guidelines and the guidelines for clinical trials of cosmetics products that are aimed at expressions and advertisement approval in Korea. It will evaluate the clinical efficacy and safety of a proposed herbal moisturising cream containing Arctium lappa L. seed extract to treat dry skin conditions and provide itch relief. Moreover, we will also employ health-related quality of life questionnaires to assess changes in the quality of life. The results of this study will be used to present the evidence needed to request advertising/display allowances, in compliance with the recently amended Cosmetics Act for advertisement in Korea. TRIAL REGISTRATION: Current Controlled Trials ISRCTN46216631.