Advancements in non-invasive skin sampling: Clinical conditions characterization via the assessment of skin surface cytokine biomarkers

The skin is increasingly recognized as a biological active organ interacting with the immune system. Given that the epidermal skin layer actively releases various cytokines, non-invasive skin sampling methods could detect these cytokines, offering insights into clinical conditions. This study aims non-invasively measuring cytokine levels directly from the skin surface to characterize different inflammatory chronic disorders in the adult and elderly population: psoriasis, diabetes type 2, rosacea, chronic kidney disease (CKD) and aging. Cytokines IL-1β, IL-8 and IL-10 were sampled from healthy subjects and patients aged 18-80 using skin surface wash technique. A well with sterile phosphate-buffered saline solution was placed on the skin for 30 min, and the extracted solution was collected from the well for further cytokine levels analysis using ELISA assay. Results show distinct cytokine profiles in different pathological processes, healthy controls, affected and unaffected areas. Aging was associated with increased IL-1β, IL-8, and IL-10 levels in skin. In diabetes, IL-1β and IL-8 levels were elevated in lesional areas, while IL-10 levels were decreased in non-lesional skin. Psoriatic lesions showed elevated levels of IL-1β and IL-8. Rosacea patients had lower IL-10 levels in both lesional and non-lesional areas. CKD patients exhibited significantly lower IL-10 levels compared to healthy individuals. In conclusion, skin surface wash-derived cytokine profiles could serve as "alert biomarkers" for disease prediction, enabling early detection. Additionally, this method's cost-effectiveness allows pre-screening of molecules in clinical studies and holds potential as a tool for biomarkers and omics analysis, enhancing disorder characterization and disease management.

Cutaneous Nrf2-Keap1 pathway modulation by environmental factors: The Dead Sea area as a test case

The skin is constantly exposed to exogenous environmental stressors and has to cope with excessive oxidative stress and tissue damage. However, exposure to moderate environmental stressors may be beneficial for the cutaneous tissue and assist in protecting against oxidative damage via the enhanced activation of the nuclear factor erythroid 2-related factor 2-Kelch-like ECH-associated protein 1 (Nrf2-Keap1) pathway. Such moderate stressors can be found in various locations around the globe. In this manuscript, we chose to focus on the Dead Sea (DS) area as a test case to study the effect of moderate stressors on the cutaneous tissue because of the unique combinations of moderate stressors in this area. The exceptional location of the DS at an altitude of -438 meters below sea level (the lowest place on earth) is responsible for its rare accumulation of moderate stressors such as high-water salinity, high atmospheric pressure, and unique solar radiation. In this manuscript, we hypothesized that the unique solar radiation in the DS area generates moderate oxidative stress in the skin leading to the induction of intracellular electrophiles, which in turn can activate the protecting Nrf2-Keap1 pathway. We showed that exposure of human skin organ culture from the same donor to solar radiation at the DS resulted in significant activation of the Nrf2-Keap1 pathway, induction of phase II enzymes, and lower apoptotic activity compared to a nearby location at a higher altitude (Jerusalem +700 m). This remarkable effect of activating the Nrf2 protecting pathway and the importance and characteristics of the solar irradiation at the DS is discussed.

Dead Sea minerals: New findings on skin and the biology beyond

BACKGROUND

Therapeutic effects of Dead Sea (DS) minerals are well established, and their unique combination is analysed and reported. DS water (DSW) is a key source for DS minerals, and various studies report the capability of DSW to alleviate symptoms of different skin disorders and to contribute to skin maintenance. However, the biological mechanisms beyond reported effects are not fully understood yet.

OBJECTIVE

To elucidate the effect of topically applied DSW via the expression of different skin biomarkers related to barrier function, homeostasis, inflammation and irritation.

METHODS

In vitro skin equivalents and ex vivo human skin organ culture were used to assess the biological effects of DSW. Epidermal barrier protein expression and DSW ions transdermal penetration were analysed on skin equivalents. β-endorphin secretion was tested on human skin organ culture. The capability of DSW to protect against skin inflammation and irritation was tested on ex vivo human skin organ culture by lipopolysaccharides and sodium dodecyl sulphate addition, respectively.

RESULTS

Topical application of DSW encouraged the expression of the barrier-related proteins: filaggrin, involucrin and transglutaminase, while transdermal penetration of calcium ions was not detected. Additionally, DSW application had increased skin secretion of β-endorphin and attenuated the expression of inflammatory and irritation-related cytokines.

CONCLUSIONS

This study reports new findings of DSW effects on skin. Signalling pathway activation is proposed as a key step that may result in a vast range of proven biological activities following skin exposure to DS minerals, and specifically DSW.

Safety evaluation of traces of nickel and chrome in cosmetics: The case of Dead Sea mud

BACKGROUND

Metal impurities such as nickel and chrome are present in natural ingredients-containing cosmetic products. These traces are unavoidable due to the ubiquitous nature of these elements. Dead Sea mud is a popular natural ingredient of cosmetic products in which nickel and chrome residues are likely to occur.

OBJECTIVE

To analyze the potential systemic and local toxicity of Dead Sea mud taking into consideration Dead Sea muds' natural content of nickel and chrome.

METHODS

The following endpoints were evaluated: (Regulation No. 1223/20, 21/12/2009) systemic and (SCCS's Notes of Guidance) local toxicity of topical application of Dead Sea mud; health reports during the last five years of commercial marketing of Dead Sea mud.

RESULTS AND CONCLUSIONS

Following exposure to Dead Sea mud, MoS (margin of safety) calculations for nickel and chrome indicate no toxicological concern for systemic toxicity. Skin sensitization is also not to be expected by exposure of normal healthy skin to Dead Sea mud. Topical application, however, is not recommended for already nickel-or chrome-sensitized persons. As risk assessment of impurities present in cosmetics may be a difficult exercise, the case of Dead Sea mud is taken here as an example of a natural material that may contain traces of unavoidable metals.

Skin smoothing effects of Dead Sea minerals: comparative profilometric evaluation of skin surface

The skin smoothing effects of three different liquid gels were compared on 20 mature women. Treatment applications were performed twice a day over a period of 4 weeks, and the skin roughness parameter (Rz) of all test participants was determined at the beginning and at the end of the study using a computer-aided laser profilometry, in accordance with DIN 4768 ff. At the end of the application period, the liquid gel with 1% of a Dead Sea mineral solution had an average skin roughness parameter reduction of 40.7%. The liquid gel without mineral additives showed an average reduction in skin roughness of 27.8%. The control gel without anti-wrinkle agents or the additives showed an average reduction of only 10.4%.

Strontium hexaferrite nanomagnets suspended in a cosmetic preparation: a convenient tool to evaluate the biological effects of surface magnetism on human skin

BACKGROUND/PURPOSE

Magnetic therapy has been popular for ages, but its therapeutic abilities remain to be demonstrated. We aimed to develop a homogeneous, stable dispersion of magnetic nanoparticles in a skin-care preparation, as a tool to analyze the biological and physiological effects of superficial magnetism in skin.

METHODS

SrFe(12)O(19) nanoparticles were generated by ultrasound, dispersed in glycerol, stabilized in Dermud cream and permanently magnetized. The magnetic cream was applied on the epidermis of human skin organ cultures. The effects on UV-induced cell toxicity, apoptosis and inflammatory cytokine expression were analyzed. A clinical test was performed to check skin moisturization.

RESULTS

Nanomagnets were found to be homogenously and stably dispersed. After magnetization, the preparation generated a magnetic field of 1-2 G. Upon cream application, no cytotoxicity and no impairment of cellular vitality were found after 24 and 48 h, respectively. The anti-apoptotic and anti-inflammatory properties of Dermud were not modified, but its long-term effect on moisturization in vivo was slightly increased.

CONCLUSION

Nanomagnetic Dermud cream can be used as a tool to analyze the biological effects of nanomagnets dispersed on the skin surface at the cellular and molecular levels, thus allowing to explore the possible therapeutic uses of superficial magnetism for skin care.

Dead Sea mineral-based cosmetics--facts and illusions

Modern Dead Sea cosmetics have developed in order to meet the demands of new regulations, technical opportunities, and today's consumer expectations for higher quality standards and proven performance. As an example of the application of this approach, the authors describe the development of a new cosmetic formulation, based on "Osmoter", a special Dead Sea mineral composition, and the evaluation of this formulation's effect on the depth of skin wrinkles, by a controlled assay. Possible mode of action is discussed.