Acne vulgaris is a chronic inflammatory multifactorial skin disorder affecting the pilosebaceous unit. It is one of the most common skin diseases leading to dermatological consultations and affecting the quality of life. In the recent years, environmental pollution has shown to exacerbate acne symptoms and severity, in addition to the various factors implicated in causing acne (stress, hormonal changes, dietary factors, hair & scalp pathologies, drugs, family history, cosmetics, lack of hygiene, occupational exposures, etc).

An increasing number of studies done in the last few years indicate a link between exacerbation of skin pathologies and exposure to airborne pollutants, such as particulate matter (PM), volatile organic compounds, ozone (O₃), nitrogen dioxide (NO₂) and sulfur dioxide (SO₂). ^1-4 Indeed, it has been reported that investigated exposure to the most frequent industry- and traffic-related air pollutants, that is, PM₁₀, PM_2.5, NO₂, SO₂, O₃ and their association with sebum level in addition to the number of inflammatory and non-inflammatory acne lesions. Increased sebum secretion and higher number of acne lesions was shown to be related to higher ambient concentrations of PM_2.5, PM₁₀ and NO₂.⁵

Air pollutants are known to induce skin damage by generating free radicals and oxygen species (ROS) and activating the aryl hydrocarbon receptor pathway. This leads to upregulation of pro-inflammatory cytokines such as interleukin 1 (IL-1),  and potentiates inflammation⁷, leading to follicular inflammation and acne. It has been suggested that IL-1 production may also contribute to hyperkeratinisation and the formation of the microcomedone.^6,8,9

At CIDP, monitoring the detrimental impact of pollution on the skin is primordial and are regularly carried out in in vitro (mono layer cells), ex vivo (human skin explants) and in vivo (human volunteers) studies, using the Controlled Pollution Exposure System (CPES). The CPES, a novel pollution aerosol system developed in-house, is capable of mimicking ambient pollution in controlled conditions of concentration of pollutants and flux.  Real time outdoor pollution exposure can also be performed in the Indian affiliate of CIDP which is located at New Delhi and which ranks among the most polluted cities in the world. In both scenario, the clinical efficacy parameters along with increased squalene monohydroperoxide (SQOOH) and malondialdehyde (MDA) content in skin swab samples and histological analyses of biopsy samples using biomarkers related to skin structure, damage and function (collagen IV, MMP1, CPD, and CD1a) when compared to baseline and placebo, helped to support the clinical benefits of test products in reducing pollution-induced skin damage and improve skin quality.¹⁰

CIDP also proposes a dual methodology where the impact of external stressors can be evaluated on skin pathologies such as atopic dermatitis or psoriasis. In this scenario, the CPES system can be used but not directly on the volunteer’s lesioned skin but on tape strips performed on a defined zone. Two different study zones, lesioned and healthy, are identified, tape stripped and exposed to different exposome including pollution. Different biomarkers including oxidative stress markers (ROS, MDA…) and proteins implicated in the skin integrity and mechanic resistance can be evaluated. Moreover, microbial peptides evolution in time and as per skin conditions (healthy or lesioned) can also be monitored.

Underlining the significance of high ambient air pollution and incidence of dermatological pathologies such as inflammatory acne, atopic dermatitis and psoriasis, more studies are needed to assess the link at a deeper level, incorporating histopathology and immunohistochemistry with biomarker analysis. Our global presence (Mauritius, Brazil, Romania and India) allows us to conduct in-depth studies along with multi-ethnic and multi-centric trials.

For more information, please visit www.cidp-cro.com.
 

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About Centre International de Développement Pharmaceutique (CIDP)
 
Established in Mauritius in 2004, CIDP, Centre International de Développement Pharmaceutique is an international Contract Research Organisation (CRO) that conducts high-performing research and clinical activities for cosmetics, pharmaceutical, medical device, and nutraceutical industries. The services provided by CIDP are segmented into the following areas of expertise: Preclinical in vitro and ex vivo testing, Clinical Research, Research & Innovation, Biostatistics and Data Management, Regulatory Affairs, Scientific and Medical Writing.
 
Comprising of a strong team of internationally qualified and experienced professionals, such as doctors, pharmacists, biologists and chemists, clinical research/trial assistants and managers, biostatisticians, and data managers, CIDP aims at aligning our business processes with requirements set out in the following standards to assure customers of our ability to deliver high quality services. All CIDP affiliates are ISO 9001:2015 certified and its Romanian affiliate is French Research Tax Credit (CIR) accredited. More recently, the Mauritian affiliate has been awarded a Silver
Medal in recognition of sustainability achievement from EcoVadis.
 
References:
 
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