Air Pollution, Autophagy, and Skin Aging: Impact of Particulate Matter (PM10) on Human Dermal Fibroblasts

Physical activity attenuated association of air pollution with estimated 10-year atherosclerotic cardiovascular disease risk in a large rural Chinese adult population: A cross-sectional study

BACKGROUND

Although long-term exposure to air pollution and physical inactivity are linked to increased risk for atherosclerotic cardiovascular diseases (ASCVD), however, the interactive effect of air pollution and physical activity (PA) on high 10-year ASCVD risk is largely unknown.

METHODS

A total of 31,162 individuals aged 35-74 years were derived from the Henan Rural Cohort Study, after individuals with personal histories of ASCVD or missing data on predictors of high 10-year ASCVD risk were excluded. Concentrations of air pollutants (nitrogen dioxide (NO₂), particulate matter with an aerodynamics diameters ≤ 1.0 µm (PM₁), ≤2.5 µm (PM_2.5) or ≤10 µm (PM₁₀)) of individuals were estimated using a spatiotemporal model based on satellites data. The metabolic equivalent (MET) of PA of each individual was evaluated using the formula: duration (hour/time) × frequency/week × MET coefficient of each type of activity. Logistic regression models were used to analyze associations between air pollutants, PA and high 10-year ASCVD risk. Interaction plots were used to describe interactive effects of air pollutants and PA on high 10-year ASCVD risk.

RESULTS

Each 1 µg/m³ increase in PM₁, PM_2.5, PM₁₀ and NO₂ were related to a 4.4% (odds ratio (OR): 1.044, 95% confidence interval (CI): 1.034, 1.056), 9.1% (OR: 1.091, 95% CI: 1.079, 1.104), 4.6% (OR: 1.046, 95% CI: 1.040, 1.051) or 6.4% (OR: 1.064, 95% CI: 1.055, 1.072) increase in high 10-year ASCVD risk (all p < 0.001), respectively; each one unit-increase in PA MET (hour/day) value was related to a 1.8% (OR: 0.982, 95% CI: 0.980, 0.985) decrease in high 10-year ASCVD risk. Negative interactive effects of PA and PM₁, PM_2.5, PM₁₀ and NO₂ on high 10-year ASCVD risk were observed (all p < 0.001).

CONCLUSION

Exposure to high levels of air pollutants were related to increase high 10-year ASCVD risk and these associations were attenuated by PA, implying that PA may be an effective method to the prevention of high 10-year ASCVD risk in highly polluted rural regions.

Additive effect of combined pollutants to UV induced skin OxInflammation damage. Evaluating the protective topical application of a cosmeceutical mixture formulation

Since the skin is one of the targets of the harmful effects of environmental insults, several studies have investigated the effects of outdoor stressors on cutaneous tissue. Ozone (O3), particulate matter (PM), and ultraviolet radiation (UV) have all been shown to induce skin damage through disruption of tissue redox homeostasis, resulting in the so called "OxInflammation" condition. However, few studies have explored whether these stressors can act synergistically in cutaneous tissues. In the present work, we evaluated whether O3, PM, and UV, which are the most common environmental skin insults, act synergistically in inducing skin damage, and whether this effect could be prevented through topical application of a cosmeceutical formulation mixture (CF Mix) containing 15% vitamin C (l-ascorbic acid), 1% vitamin E (α-tocopherol), and 0.5% ferulic acid. Human skin explants obtained from three different subjects were sequentially exposed to 200 mJ UV light, 0.25 ppm O3 for 2 h, and 30 min of diesel engine exhaust (DEE), alone or in combination for 4 days (time point D1 and D4). We observed a clear additive effect of O3 and DEE in combination with UV in increasing levels of several oxidative (4HNE, HO-1) and inflammatory (COX2, NF-κB) markers and loss of barrier-associated proteins, such as filaggrin and involucrin. Furthermore, daily topical pre-treatment with the CF Mix prevented upregulation of the inflammatory and oxidative markers and the loss of both involucrin and filaggrin. In conclusion, this study is the first to investigate the combined effects of three of the most harmful outdoor stressors on human skin and suggests that daily topical application may prevent pollution-induced skin damage.

Effect of fluticasone propionate on human nasal fibroblasts exposed to urban particulate matter

OBJECTIVE

Particulate matter (PM), which contains organic compounds and toxic metals, is the major cause of air pollution. PM enters the body, causing various health problems. Although the effects of PM on the lower respiratory tract have been extensively investigated, the effects on the upper respiratory tract (including the nasal cavity) require further evaluation. To investigate the effect of fluticasone propionate (FP) on nasal fibroblasts exposed to UPM.

METHODS

Samples of inferior turbinate tissue were obtained from six patients. The fibroblasts isolated from these samples were exposed to UPM and/or FP. The expression of interleukin (IL)-6, CXC chemokine ligand (CXCL) 1, IL-1β, and tumour necrosis factor-alpha (TNF-α) in nasal fibroblasts was analysed using real-time PCR and enzyme-linked immunosorbent assays. The protein levels of nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) were analysed by western blotting.

RESULTS

FP reversed the UPM-induced reduction in cell viability. The mRNA and protein levels of IL-6, CXCL1, IL-1β, and TNF-α were significantly increased by UPM. FP reversed the UPM-induced increases in the protein levels of NF-κB and phosphorylated-STAT3 in a dose-dependent manner. In addition, TNF-α, an inducer of NF-κB, reversed the FP-induced reduction in the levels of signalling molecules.

CONCLUSION

UPM induces the expression of IL-6, CXCL1, IL-1β, and TNF-α in nasal fibroblasts and this effect is reversed by FP via the STAT3 and NF-κB signalling pathways. These results suggest that FP has therapeutic potential for nasal diseases related to UPM, such as allergic and chronic rhinitis.

Particulate matter pollution and hospital outpatient visits for endocrine, digestive, urological, and dermatological diseases in Nanjing, China

Clinical or pathological evidence demonstrated that air pollution could undermine other organ systems of human body besides respiratory and circulation systems. Investigations that directly relate hospital outpatient visits for endocrine (ENDO), digestive (DIGE), urological (UROL), and dermatological (DERM) diseases categories with ambient particulate matter (PM) are still lacking, particularly in heavily polluted cities. Here, we conducted a time-series analysis using 812,624, 1,111,342, 539,803, and 741,662 hospital visits for ENDO, DIGE, UROL, and DERM, respectively, in Nanjing, China from 2013 to 2019. A generalized additive model was applied to estimate the exposure-response associations. Results showed that a 10 μg/m³ increase in PM_2.5 concentration on lag 0 day was significantly associated with 0.59% (95% CI: 0.30%, 0.88%), 0.43% (0.15%, 0.70%), 0.36% (0.06%, 0.66%), and 0.65% (0.42%, 0.87%) increase for ENDO, DIGE, UROL, and DERM hospital visits, respectively. The estimated effects of PM₁₀ were slightly smaller but still statistically significant. The magnitude and significance of the associations between PM and four health outcomes were sensitive to additional adjustment for co-pollutants. Exposure-response relationships were linear for PM concentrations lower than 100 μg/m³ but the curves became nonlinear across the full range of exposures due to a flatten slope at higher concentrations. We also explored the effect modifications by season (cold or warm), age (5-18, 18-64, 65-74, or 75+ years), and sex (male or female). Results showed that the DERM-related population aged 65 years or older was more vulnerable to PM exposure, compared with the 5 to 17-year age group; the DERM-related population aged 75 years or older and 65 years or older was more vulnerable to PM_2.5 and PM₁₀ exposure, respectively, compared with the 18 to 64-year age group. Our study provided suggestive evidence that ambient PM pollution was associated with ENDO, DIGE, UROL, and DERM outpatient hospital visits in Nanjing, China.

Comparative analysis of urban road dust compositions in relation to their potential human health impacts

This study investigated the chemical components of fine urban road dust from seven sampling sites, based on which we could predict potential human health effects. The elemental compositions, including the contents of metals and volatile or semivolatile organic compounds, were determined to establish comprehensive chemical profiles of solid road dust. The chemical profiles, consisting of C: H ratio, metal contents, and relative abundances of organic compounds, provided a chemical signature for road dust. To overall cytotoxicity values ranging between 7 and 58%, water extracts contributed less than 15%, and cell death mainly occurred via direct contact with solid-phase components, which possibly indicates that the selected chemical profile of solid-phase road dust components could serve as a strong predictor for BJ and WI-38 cytotoxicity. Pure metal oxides (Cr₂O₃, CuO, Fe₂O₃, MnO₂, NiO, or ZnO) exhibited a positive dose-response, and the corresponding metal contents in solid road dust were well correlated with cell viability. The principal component analysis (PCA) results suggested that the metal contents were stronger predictors of cytotoxicity than the benzene derivative or hydrocarbon contents. The chemical profiles established in this study could be further utilized to identify candidate health hazard factors in road dust.

A novel multifunctional skin care formulation with a unique blend of antipollution, brightening and antiaging active complexes

BACKGROUND

High demand on anti-aging skin care encourage the improvement and development of more personalized formulations with additional benefits for general skin health and age associated skin signs. The skin aging physical and biological phenotypes manifest differently between diverse ethnic populations. A highly polluted environment can be viewed as an extrinsic factor accelerating the skin aging process.

AIM

To develop a unique formula with active complexes, having multifunctional effects for anti-pollution, brightening and anti-aging/barrier strengthening purposes with confirmed activities in vitro and ex vivo skin models, suitable for polluted skin.

METHODS

In vitro culture model with primary human skin cells, ex vivo studies with full-thickness human skin, melanocyte 3D coculture model, gene expression of epidermal and dermal genes, anti-glycation, proteasomal activity, melanin, and cytokine assays.

RESULTS

In vitro and ex vivo studies clearly demonstrated that diglucosyl gallic acid (active A) and the formulation complex inhibited pollution mediated MMP1 protein, CYP1A1 gene expression, and IL-6 protein secretion, while caprylic/capric triglyceride, diacetyl boldine (active B) had anti-melanogenic effect in in vitro primary melanocyte monoculture and 3D spheroid model. Another active compound, acetyl dipeptide 1 cetyl ester (active D), significantly upregulated epidermal barrier genes (Aquaporin 3 [AQP3], Filaggrin [FLG], caspase 14, and keratin 10) in human primary keratinocytes. Interestingly, both acetyl dipeptide 1 cetyl ester (active D) and niacinamide (active C) improved dermal gene expression (fibrillin-1, Collagen type 1 alpha 1, Decorin, Lysyl oxidase-like 1) and, moreover, had significant anti-glycant and proteasomal promoter activity in human primary fibroblasts.

CONCLUSION

Considering consumers need in heavily polluted areas, we developed a multipurpose formulation comprised of unique active complexes toward pollution, pollution induced inflammation, skin brightening, and antiaging concerns with beneficial results demonstrated by in vitro and ex vivo studies.

Can Plant Phenolic Compounds Protect the Skin from Airborne Particulate Matter?

The skin is directly exposed to the polluted atmospheric environment, and skin diseases, such as atopic dermatitis and acne vulgaris, can be induced or exacerbated by airborne particulate matter (PM). PM can also promote premature skin aging with its accompanying functional and morphological changes. PM-induced skin diseases and premature skin aging are largely mediated by reactive oxygen species (ROS), and the harmful effects of PM may be ameliorated by safe and effective natural antioxidants. Experimental studies have shown that the extracts and phenolic compounds derived from many plants, such as cocoa, green tea, grape, pomegranate, and some marine algae, have antioxidant and anti-inflammatory effects on PM-exposed cells. The phenolic compounds can decrease the levels of ROS in cells and/or enhance cellular antioxidant capacity and, thereby, can attenuate PM-induced oxidative damage to nucleic acids, proteins, and lipids. They also lower the levels of cytokines, chemokines, cell adhesion molecules, prostaglandins, and matrix metalloproteinases implicated in cellular inflammatory responses to PM. Although there is still much research to be done, current studies in this field suggest that plant-derived phenolic compounds may have a protective effect on skin exposed to high levels of air pollution.

Improvement of Skin Penetration, Antipollutant Activity and Skin Hydration of 7,3',4'-Trihydroxyisoflavone Cyclodextrin Inclusion Complex

As is known, many antioxidants from plant extracts have been used as additives in skincare products to prevent skin damage following overexposure to environmental pollutants. 7,3′,4′-trihydroxyisoflavone (734THIF), an isoflavone compound, possesses various biological activities, including antioxidant, antityrosinase, photodamage protection, and anticancer effects. Unfortunately, 734THIF has poor water solubility, which limits its skin penetration and absorption, and subsequently influences its biological activity. The aim of the present study was to investigate the mechanisms for the improvement in water solubility and skin penetration of 2-hydroxypropyl-β-cyclodextrin (HPBCD) inclusion complex with 734THIF (5-7HP). We also determined its photostability, antipollutant activity in HaCaT keratinocytes, and moisturizing effect in human subjects. Our results showed that 734THIF was embedded into the lipophilic inner cavity of HPBCD and its water solubility and skin penetration were thereby improved through amorphous transformation, surface area enhancement, and hydrogen bonding formation between 734THIF and HPBCD. In addition, 5-7HP inhibited PM-induced ROS generation and then downregulated ROS-mediated COX-2 and MMP9 production and AQP-3 consumption by inhibiting the phosphorylation of MAPKs. Consequently, we suggest that 5-7HP is a safe and photostable topical ingredient to enhance the skin penetration of 734THIF and skin hydration, and therefore 5-7HP may be used as an antipollutant additive in skin care products.

A novel water-based anti-aging suncare formulation provides multifaceted protection and repair against environmental aggressors: evidence from in vitro, ex vivo, and clinical studies

Background

Ultraviolet (UV) radiation is an established cause of skin aging, and the role of pollution is increasingly acknowledged. In this study, we evaluated the efficacy of an antipollution and anti-aging suncare product in in vitro, ex vivo, and clinical studies.

Methods

We assessed 1) sunburn cell (SBC) and cyclobutane pyrimidine dimer (CPD) formation and gene expression profile in reconstructed human epidermis following solar irradiation, 2) malondialdehyde (MDA) level, Nrf2 immunostaining, and genetic expression in skin explants exposed to pollution, 3) carbon particle adhesion to healthy forearm skin in a clinical study, and 4) skin firmness, elasticity, and pigmentation spots in healthy women following 56 days of application.

Results

1) The product fully protected against CPD formation, and provided a high protection against SBC formation, with levels close to non-irradiated samples. Expression of genes encoding pro-inflammatory and oxidative stress response markers was lower in product-treated than untreated skin. 2) Compared with pollution-exposed untreated controls, product-treated skin had 23% lower MDA levels (P<0.01), weaker Nrf2 immunostaining, and attenuated upregulation of CYP1A1. 3) The product significantly decreased adhesion of carbon particles to the skin (15.2% less than control; P<0.01). 4) Clinically, product use led to a decrease in brown spots, with a relative reduction in the count of −1.9% (NS), and in area, −5.0% (P<0.01), and decrease in UV spots, with a relative reduction of −6.9% (P<0.01) and −9.3% (P=0.02) for count and area, respectively. Firmness increased significantly by 14.1% (P<0.01). Participants reported skin was more even in tone (80%), more moisturized (93%), and firmer (74%).

Conclusion

This water-based anti-aging SPF50 suncare formulation containing photolyase encapsulated in liposome, active biopeptides, antioxidants, and hyaluronic acid provides multifaceted protection and repair action against pollution and UV-induced skin aging, ideal for everyday use.

Environmental Stressors on Skin Aging. Mechanistic Insights

The skin is the main barrier that protects us against environmental stressors (physical, chemical, and biological). These stressors, combined with internal factors, are responsible for cutaneous aging. Furthermore, they negatively affect the skin and increase the risk of cutaneous diseases, particularly skin cancer. This review addresses the impact of environmental stressors on skin aging, especially those related to general and specific external factors (lifestyle, occupation, pollutants, and light exposure). More specifically, we have evaluated ambient air pollution, household air pollutants from non-combustion sources, and exposure to light (ultraviolet radiation and blue and red light). We approach the molecular pathways involved in skin aging and pathology as a result of exposure to these external environmental stressors. Finally, we reflect on how components of environmental stress can interact with ultraviolet radiation to cause cell damage and the critical importance of knowing the mechanisms to develop new therapies to maintain the skin without damage in old age and to repair its diseases.

Marine Alga Ecklonia cava Extract and Dieckol Attenuate Prostaglandin E2 Production in HaCaT Keratinocytes Exposed to Airborne Particulate Matter

Atmospheric particulate matter (PM) is an important cause of skin damage, and an increasing number of studies have been conducted to discover safe, natural materials that can alleviate the oxidative stress and inflammation caused by PM. It has been previously shown that the extract of Ecklonia cava Kjellman, a perennial brown macroalga, can alleviate oxidative stress in epidermal keratinocytes exposed to PM less than 10 microns in diameter (PM10). The present study was undertaken to further examine the anti-inflammatory effects of E. cava extract and its major polyphenolic constituent, dieckol. HaCaT keratinocytes were exposed to PM10 in the presence or absence of E. cava extract or dieckol and analyzed for their viability, prostaglandin E₂ (PGE₂) release, and gene expression of cyclooxygenase (COX)-1, COX-2, microsomal prostaglandin E₂ synthase (mPGES)-1, mPGES-2, and cytosolic prostaglandin E₂ synthase (cPGES). PM10 treatment decreased cell viability and increased the production of PGE₂, and these changes were partially abrogated by E. cava extract. E. cava extract also attenuated the expression of COX-1, COX-2, and mPGES-2 stimulated by PM10. Dieckol attenuated PGE₂ production and the gene expression of COX-1, COX-2, and mPGES-1 stimulated by PM10. This study demonstrates that E. cava extract and dieckol alleviate airborne PM10-induced PGE₂ production in keratinocytes through the inhibition of gene expression of COX-1, COX-2, mPGES-1, and/or mPGES-2. Thus, E. cava extract and dieckol are potentially useful natural cosmetic ingredients for counteracting the pro-inflammatory effects of airborne PM.

Phytomelatonin Regulates Keratinocytes Homeostasis Counteracting Aging Process

Phytomelatonin (PM) gained the greatest interest for its application in agriculture and its use to improve human health conditions. PM based supplement has been shown to possess antioxidant capabilities because it functions as a free radical scavenger. Reactive Oxygen Species (ROS), induced by both intrinsic (peroxide production) and extrinsic (UV-radiation) factors are biochemical mediators crucial in skin aging. Skin aging is also regulated by specific microRNAs (miRs). Herein we have shown the effect of PM free radical scavengers on the human keratinocyte cell line HaCat and on ROS formation induced by both extrinsic and intrinsic factors as well as their capability to positively modulate a member of the hsa-miR-29 family linked to aging. Our result highlights the regulatory role of PM for the keratinocytes homeostasis.

Skin Aging Estimation Scheme Based on Lifestyle and Dermoscopy Image Analysis

Besides genetic characteristics, people also undergo a process of skin aging under the influence of diverse factors such as sun exposure, food intake, sleeping patterns, and drinking habits, which are closely related to their personal lifestyle. So far, many studies have been conducted to analyze skin conditions quantitatively. However, to describe the current skin condition or predict future skin aging effectively, we need to understand the correlation between skin aging and lifestyle. In this study, we first demonstrate how to trace people’s skin condition accurately using scale-invariant feature transform and the color histogram intersection method. Then, we show how to estimate skin texture aging depending on the lifestyle by considering various features from face, neck, and hand dermoscopy images. Lastly, we describe how to predict future skin conditions in terms of skin texture features. Based on the Pearson correlation, we describe the correlation between skin aging and lifestyle, and estimate skin aging according to lifestyle using the polynomial regression and support vector regression models. We evaluate the performance of our proposed scheme through various experiments.