Effects of Particulate Matter in a Mouse Model of Oxazolone-Induced Atopic Dermatitis

Abstract

Background Recent epidemiological studies have demonstrated that air pollution is associated with the inflammatory response and may aggravate inflammatory skin diseases such as atopic dermatitis (AD). However, it is unclear whether particulate matter (PM) aggravates AD symptoms. Objective The aim of this study was to investigate whether PM exposure affects the skin barrier dysfunction and aggravates AD symptoms using human keratinocytes (HaCaT) cells and a mouse model of oxazolone-induced AD-like skin. Methods Standard reference material (SRM) 1649b, which mainly comprises polycyclic aromatic hydrocarbons, was used as the reference PM. HaCaT cells and mouse model of oxazolone-induced AD-like skin were treated with PM. The mRNA or protein expression levels of stratum corneum (SC) and tight junction (TJ) proteins, inflammatory cytokines, as well as clinical and histological changes of the AD-like skin of mouse model were evaluated. The expression of genes and proteins was analyzed by real-time polymerase chain reaction and Western blotting. Levels of inflammatory cytokines were measured by enzyme-linked immunosorbent assay. Results The results revealed that PM downregulates the expression levels of several SC and TJ-related proteins in the mouse model with AD-like skin. Clinically, epidermal and dermal thickness was significantly increased and dermal inflammation was prominent in PM treated AD-like skin. Conclusion In conclusion, we found that PM aggravates skin barrier dysfunction, clinically augmenting epidermal and dermal thickening with dermal inflammation in AD-like skin. These results suggest that PM may trigger the exacerbation of AD symptoms via skin barrier dysfunction-related mechanisms.

Development of In Vitro Co-Culture Model to Mimic the Cell to Cell Communication in Response to Urban PM2.5

“…Conversely, the expression of skin barrier markers FLG and LOR decreased. The cytokine secretion pattern after exposure to PM appeared to correspond to the in vivo effects related to PM previously shown 33 .…”

“…Triple-cell cultures consisting of various cell types can mimic realistic interactions in human skin and is a more reliable evaluation model than traditional cell monocultures 15 . On our previous study 33 , the effects of air pollutants on atopic dermatitis were evaluated by treating keratinocytes with IL-4, IL-13 and PM. Comparison of mRNA and protein expression levels between the single cell model and triple co-culture model showed that there are significant differences in the expression of inflammatory and skin barrier markers in the triple co-culture model even without IL-4 or IL-13 cytokine treatment.…”

Effects of Air Pollution on Cellular Senescence and Skin Aging

“…Particulate matter (PM) is one of the main components of air pollution and is defined as a mixture of gas containing liquid and/or solid droplets varying in size and composition [ 86 , 88 ]. Particles contained in PM include substances such as metals, minerals, organic toxins, tobacco smoke, pollen, allergens, and smog [ 89 ]. These particles are classified according to their aerodynamic diameter (Dp) in three categories: particles with Dp bellow 10 µm are named “coarse particles” or PM 10 and include components of dust, soil, and dusty emission from industries; particles with Dp between 0.1 and 2.5 µm are called “particle matter” or PM 2.5 and are mainly derived from open fires, automobile exhausts, and power plants [ 90 ]; and particles with Dp bellow 0.1 µm are called “ultrafine particles” or PM 0.1 and mainly consist of emissions of diesel-powered engines [ 86 ].…”

Preventative Effects of Antioxidants against PM10 on Serum IgE Concentration, Mast Cell Counts, Inflammatory Cytokines, and Keratinocyte Differentiation Markers in DNCB-Induced Atopic Dermatitis Mouse Model

“…They can affect the human body via the synthesis of reactive oxygen species (ROS) [ 4 , 5 , 6 , 7 ]. Oxidative stress can cause or aggravate the extrinsic aging of the skin and inflammatory skin disorders [ 8 , 9 , 10 , 11 , 12 , 13 ].…”