Age-related changes in skin barrier function - Quantitative evaluation of 150 female subjects

Women's skin care behaviors: How to influence sunscreen use

BACKGROUND

It is well known that women have been plagued by various skin problems. However, research on the characteristics of women's skin at different ages is still inadequate. In addition, there is a lack of research on the extent of women's skincare habits and skin care awareness.

METHODS

A cross-sectional survey on skin was carried out in Shanghai, China, which was conducted by means of a questionnaire. 3678 women, aged 18-59 years, participated in the study. The information collected focused on the importance they place on their skin, the skin problems they have, and their use and perception of skin care products.

RESULTS

Before the age of 25, the most common skin problems that women face are dryness and oiliness, while after the age of 30, skin-ageing issues begin to appear and worsen with age. In addition, the higher the level of education, the higher the frequency of and compliance with sunscreen use, and the economy also affects women's use of sunscreen. Importantly, the importance women place on their skin and the level of sunscreen awareness affects women's use of sunscreen.

CONCLUSIONS

This study was conducted to understand the skin characteristics of women of different age groups as well as to determine the factors that influence the use of sunscreens, which will not only promote women's skin care practices and product development, but also provide important clues for future activities on sunscreen use and health promotion.

Quantitative skin surface hydration measurement by visible optical image processing: A pilot study

BACKGROUND

Skin barrier function is significantly impacted by skin moisture. Most non-invasive evaluation techniques to measure skin surface hydration relying on its electrical properties, which are limited in scope and have unstable operations. Applying image processing for skin hydration assessment is uncommon, with an emphasis on skin-capacitive pictures and near-infrared images in general, which demand a certain spectrum. As a result, there is an increasing need for wide-area skin hydration evaluation and mapping.

OBJECTIVE

The study aims to propose a quantitative evaluation algorithm for skin surface hydration from visible-light images.

MATERIALS AND METHODS

Three devices were applied to measure skin hydration: skin image capture device and two recognized commercial skin devices. A digital image processing system creates a new index, called GVR, to symbolize skin surface moisture. The CLAHE algorithm was applied to enhance the contrast of skin image, and after calculating it with the monochrome image, the skin reflectance image was segmented. The GVR was estimated using the values of the individual sites and the entire skin. The correlation coefficient between the three methods was examined using statistical analysis to assess the performance of GVR.

RESULTS

Skin hydration estimated from visible-light images is influenced by the entire facial structure in addition to specific areas. The electrical and visible image evaluations showed a strong association with a significant difference.

CONCLUSION

It was discovered that reflecting measures from visible images provide a quick and efficient way to quantify the moisture of the skin's surface.

Considerations for managing elderly patients with atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) diagnosis in elderly is challenging, due to its clinical polymorphism and the lack of diagnostic biomarkers. Moreover, the chronicity of the disease and the complex pathogenetic mechanism, make elderly AD management challenging.

AREAS COVERED

A narrative review of the current literature was performed using the PubMed, Medline, Embase, and Cochrane Skin databases, by researching the following terms: 'atopic dermatitis,' 'clinical phenotypes,' 'eczema,' 'elderly patients,' 'elderly type atopic dermatitis,' 'eczema clinical presentation.' The aim was to report the current knowledge on pathogenesis, clinical presentation, and treatment options of elderly AD.

EXPERT OPINION

Elderly type AD has recently been identified as a separate entity, with an increasing prevalence. With aging, both immunosenescence and barrier alterations can cause or modify AD presentation. Moreover, a chronic proinflammatory state (so-called 'inflammaging') is often present in elderly subjects. Older patients with AD may present with peculiar immunophenotypic profile, making AD diagnosis challenging. Similarly, the chronicity of the disease and the complex pathogenetic mechanism, make AD management a challenge. Indeed, systemic therapies for AD are often contraindicated or not tolerated and the management of elderly type AD is often burdened with numerous difficulties, leading to undertreated disease. Even if dupilumab and tralokinumab represent a valuable therapeutic weapon, more data on safety of JAK inhibitors are required.

Skin Barrier Function Assessment: Electrical Impedance Spectroscopy Is Less Influenced by Daily Routine Activities Than Transepidermal Water Loss

BACKGROUND

Skin barrier function assessment is commonly done by measuring transepidermal water loss (TEWL). An important limitation of this method is the influence of intrinsic and extrinsic factors. Electrical impedance spectroscopy (EIS) is a lesser-established method for skin barrier function assessment. Some influential factors have been described, but no guidelines exist regarding the standardization of these measurements.

OBJECTIVE

To evaluate the effect size of daily routine activities on TEWL and EIS, as well as their correlation with age and anatomical differences.

METHODS

Healthy participants (n=31) were stratified into three age groups (18-29, 30-49, and ≥50 years). In a climate-controlled room, EIS and TEWL measurements were performed on the left and right volar forearm and abdomen.

RESULTS

Body cream application decreased TEWL and EIS values after 15 and 90 minutes. Skin washing decreased TEWL for 15 minutes and EIS values for at least 90 minutes. TEWL was increased 5 minutes after moderate to intense exercise. Coffee intake increased TEWL on the abdomen after 60 minutes. TEWL and EIS values did not correlate with participants' age and no anatomical differences were observed. No correlation was observed between TEWL and EIS.

CONCLUSION

Body cream application and skin washing should be avoided at least 90 minutes prior to measurements of TEWL and EIS. Exercise and coffee intake should also be avoided prior to TEWL measurements. EIS may be a promising tool for skin barrier function assessment as it is less affected by daily routine activities than TEWL.

Potential Role of the Skin in Hypertension Risk Through Water Conservation

Previous basic and clinical investigations have identified various pathogenic factors and determinants of risk that contribute to hypertension. Nevertheless, the pathogenesis of hypertension has not been fully elucidated. Moreover, despite the availability of antihypertensive medications for the management of blood pressure, treatments that address the full spectrum of the pathophysiological defects underpinning hypertension remain to be identified. To further investigate the mechanisms of primary hypertension, it is imperative to consider novel potential aspects, such as fluid management by the skin, in addition to the conventional risk factors. There is a close association between body fluid regulation and blood pressure, and the kidney, which, as the principal organ responsible for body fluid homeostasis, is the primary target for research in the field of hypertension. In addition, the skin functions as a biological barrier, potentially contributing to body fluid regulation. In this review, we propose the hypothesis that changes in skin water conservation are associated with hypertension risk based on recent findings. Further studies are required to clarify whether this novel hypothesis is limited to specific hypertension or applies to physiological blood pressure regulation.

Role of autophagy in skin photoaging: A narrative review

As the largest organ of the human body, the skin serves as the primary barrier against external damage. The continuous increase in human activities and environmental pollution has resulted in the ongoing depletion of the ozone layer. Excessive exposure to ultraviolet (UV) radiation enhances the impact of external factors on the skin, leading to photoaging. Photoaging causes physical and psychological damage to the human body. The prevention and management of photoaging have attracted increased attention in recent years. Despite significant progress in understanding and mitigating UV-induced photoaging, the precise mechanisms through which autophagy contributes to the prevention of photoaging remain unclear. Given the important role of autophagy in repairing UV-induced DNA damage and scavenging oxidized lipids, autophagy is considered a novel strategy for preventing the occurrence of photoaging and other UV light-induced skin diseases. This review aims to elucidate the biochemical and clinical features of photoaging, the relationship of skin photoaging and chronological aging, the mechanisms underlying skin photoaging and autophagy, and the role of autophagy in skin photoaging.

Evaluating the Irritant Factors of Silicone and Hydrocolloid Skin Contact Adhesives Using Trans-Epidermal Water Loss, Protein Stripping, Erythema, and Ease of Removal

A composite silicone skin adhesive material was designed to improve its water vapor permeability to offer advantages to wearer comfort compared to existing skin adhesive dressings available (including perforated silicone and hydrocolloid products). The chemical and mechanical properties of this novel dressing were analyzed to show that it has a high creep compliance, offering anisotropic elasticity that is likely to place less stress on the skin. A participant study was carried out in which 31 participants wore a novel silicone skin adhesive (Sil2) and a hydrocolloid competitor and were monitored for physiological response to the dressings. Trans-epidermal water loss (TEWL) was measured pre- and postwear to determine impairment of skin barrier function. Sil2 exhibited a higher vapor permeability than the hydrocolloid dressings during wear. Peel strength measurements and dye counter staining of the removed dressings showed that the hydrocolloid had a higher adhesion to the participants' skin, resulting in a greater removal of proteins from the stratum corneum and a higher pain rating from participants on removal. Once the dressings were removed, TEWL of the participants skin beneath the Sil2 was close to normal in comparison to the hydrocolloid dressings that showed an increase in skin TEWL, indicating that the skin had been highly occluded. Analysis of the skin immediately after removal showed a higher incidence of erythema following application of hydrocolloid dressings (>60%) compared to Sil2, (<30%). In summary, this modified silicone formulation demonstrates superior skin protection properties compared to hydrocolloid dressings and is more suitable for use as a skin adhesive.

Chronological aging impacts abundance, function and microRNA content of extracellular vesicles produced by human epidermal keratinocytes

The disturbance of intercellular communication is one of the hallmarks of aging. The goal of this study is to clarify the impact of chronological aging on extracellular vesicles (EVs), a key mode of communication in mammalian tissues. We focused on epidermal keratinocytes, the main cells of the outer protective layer of the skin which is strongly impaired in the skin of elderly. EVs were purified from conditioned medium of primary keratinocytes isolated from infant or aged adult skin. A significant increase of the relative number of EVs released from aged keratinocytes was observed whereas their size distribution was not modified. By small RNA sequencing, we described a specific microRNA (miRNA) signature of aged EVs with an increase abundance of miR-30a, a key regulator of barrier function in human epidermis. EVs from aged keratinocytes were found to be able to reduce the proliferation of young keratinocytes, to impact their organogenesis properties in a reconstructed epidermis model and to slow down the early steps of skin wound healing in mice, three features observed in aged epidermis. This work reveals that intercellular communication mediated by EVs is modulated during aging process in keratinocytes and might be involved in the functional defects observed in aged skin.

Evaluation of Scalp Hydration and pH Values in Hijab-Wearing and Non-Hijab-Wearing Women

Introduction

Indonesia is the most populous Muslim-majority country, where some women wear hijab covering their scalp and neck. Some hijab-wearing women complain of scalp problems eg, itch, dandruff, and hair loss, which might be related to severe and chronic skin barrier impairment due to occlusion. Excessive water accumulation in the occluded stratum corneum might result in increased permeability, followed by increased skin pH values. This study aimed to evaluate scalp hydration and pH values in hijab-wearing and non-hijab-wearing women.

Material and Methods

This was a cross-sectional comparative analytical study using stratified random sampling methods conducted on 63 subjects, who were divided into two groups, consisting of 33 hijab-wearing and 30 non-hijab-wearing women. Both groups underwent physical examination and their medical history recorded. Scalp hydration was measured using a Corneometer (Courage + Khazaka, Koln, Germany), and scalp pH value was measured using a Skin & Scalp pH Tester (Hanna Instruments® HI981037, Rumania). This study was conducted at the Dermatology and Venereology Clinic of Hasan Sadikin General Hospital Bandung.

Results

The mean scalp hydration and pH values were 18.34 ± 2.91 AU and 4.93 ± 0.17, respectively, in hijab-wearing women. Meanwhile, the mean scalp hydration and pH values were 17.71 ± 3.35 AU and 4.91 ± 0.16, respectively, in non-hijab-wearing women. The difference of scalp hydration and pH values between the groups was not statistically significant based on the independent t-test, with p-values of 0.430 and 0.597, respectively.

Conclusion

Scalp hydration and pH values in hijab-wearing and non-hijab-wearing women did not differ significantly. Hijab-wearing women should not worry about scalp barrier impairment as long as they do not have any history of underlying scalp and skin disorders, and do not wear hijab in wet condition.

Investigating causal relationships between obesity and skin barrier function in a multi-ethnic Asian general population cohort

BACKGROUND

Skin diseases impact significantly on the quality of life and psychology of patients. Obesity has been observed as a risk factor for skin diseases. Skin epidermal barrier dysfunctions are typical manifestations across several dermatological disturbances.

OBJECTIVES

We aim to establish the association between obesity and skin physiology measurements and investigate whether obesity may play a possible causal role on skin barrier dysfunction.

METHODS

We investigated the relationship of obesity with skin physiology measurements, namely transepidermal water loss (TEWL), skin surface moisture and skin pH in an Asian population cohort (n = 9990). To assess for a possible causal association between body mass index (BMI) and skin physiology measurements, we performed Mendelian Randomization (MR), along with subsequent additional analyses to assess the potential causal impact of known socioeconomic and comorbidities of obesity on TEWL.

RESULTS

Every 1 kg/m2 increase in BMI was associated with a 0.221% (95%CI: 0.144-0.298) increase in TEWL (P = 2.82E-08), a 0.336% (95%CI: 0.148-0.524) decrease in skin moisture (P = 4.66E-04) and a 0.184% (95%CI: 0.144-0.224) decrease in pH (P = 1.36E-19), adjusting for age, gender, and ethnicity. Relationships for both TEWL and pH with BMI remained strong (Beta 0.354; 95%CI: 0.189-0.520 and Beta -0.170; 95%CI: -0.253 to -0.087, respectively) even after adjusting for known confounders, with MR experiments further supporting BMI's possible causal relationship with TEWL. Based on additional MR performed, none of the socioeconomic and comorbidities of obesity investigated are likely to have possible causal relationships with TEWL.

CONCLUSION

We establish strong association of BMI with TEWL and skin pH, with MR results suggestive of a possible causal relationship of obesity with TEWL. It emphasizes the potential impact of obesity on skin barrier function and therefore opportunity for primary prevention.

The aged extracellular matrix and the profibrotic role of senescence-associated secretory phenotype

Idiopathic pulmonary fibrosis (IPF) is an irreversible and fatal lung disease that is primarily found in the elderly population, and several studies have demonstrated that aging is the major risk factor for IPF. IPF is characterized by the presence of apoptosis-resistant, senescent fibroblasts that generate an excessively stiff extracellular matrix (ECM). The ECM profoundly affects cellular functions and tissue homeostasis, and an aberrant ECM is closely associated with the development of lung fibrosis. Aging progressively alters ECM components and is associated with the accumulation of senescent cells that promote age-related tissue dysfunction through the expression of factors linked to a senescence-associated secretary phenotype (SASP). There is growing evidence that SASP factors affect various cell behaviors and influence ECM turnover in lung tissue through autocrine and/or paracrine signaling mechanisms. Since life expectancy is increasing worldwide, it is important to elucidate how aging affects ECM dynamics and turnover via SASP and thereby promotes lung fibrosis. In this review, we will focus on the molecular properties of SASP and its regulatory mechanisms. Furthermore, the pathophysiological process of ECM remodeling by SASP factors and the influence of an altered ECM from aged lungs on the development of lung fibrosis will be highlighted. Finally, recent attempts to target ECM alteration and senescent cells to modulate fibrosis will be introduced.NEW & NOTEWORTHY Aging is the most prominent nonmodifiable risk factor for various human diseases including Idiopathic pulmonary fibrosis. Aging progressively alters extracellular matrix components and is associated with the accumulation of senescent cells that promote age-related tissue dysfunction. In this review, we will discuss the pathological impact of aging and senescence on lung fibrosis via senescence-associated secretary phenotype factors and potential therapeutic approaches to limit the progression of lung fibrosis.

Transepidermal water loss and stratum corneum hydration in forearm versus hand palm

BACKGROUND

Skin measurements of transepidermal water loss (TEWL) and stratum corneum hydration (SCH) reflect different aspects of skin physiology. Since epidermal water loss depends on epidermal-to-air water vapor gradients, a possible quantitative relationship between TEWL and SCH may exist. This investigation's purpose was to test the possible TEWL-SCH relationship.

MATERIALS AND METHODS

SCH and TEWL were measured noninvasively on forearm and palmer thenar eminence (hand) in 40 young adults (20 males) along with total body fat percentage (FAT) via bioimpedance.

RESULTS

A significant positive nonlinear correlation (p < 0.001) was detected between SCH and TEWL in hands of the male cohort that occurred when SCH exceeded a threshold level. This threshold level was not exceeded in male or female forearms and forearms did not display a SCH-TEWL correlation. There was a weak inverse dependence of TEWL on FAT on both forearm and hand (p < 0.05), but no SCH-FAT relationship was observed. TEWL values on the forearm and hand were moderately correlated with each other (p = 0.002) but SCH values were not.

CONCLUSION

The findings clarify the relationship between forearm and palmer hydration and TEWL values, and their relationship to total body fat percentages in young healthy adults. The significant correlation between palmer stratum corneum hydration and palmer TEWL that was discovered in the male but not the female cohort suggests a threshold hydration level for which TEWL depends both on skin barrier function and stratum corneum hydration. This implies that conditions with increased SCH may in part account for elevated TEWL values.

Measurement of human skin moisture via high-frequency spectroscopy

High-frequency spectroscopy (HFS) is an analytical method that is sensitive to slight changes in the dielectric properties of materials. Since water has high permittivity, HFS can be used to detect changes in water content in materials. In this study, we employed HFS to measure human skin moisture during a water sorption-desorption test. Skin without any treatment showed a resonance peak at approximately 1150 MHz. Furthermore, the peak shifted to lower frequency immediately after the application of water to the skin and gradually returned to its original frequency as time progressed. The resonance frequency obtained via least-squares fitting showed that the applied water remained in the skin after 240 s from the beginning of the measurement. These results illustrated that HFS measurements can monitor the progression of decreasing moisture content in human skin during a water sorption-desorption test.

Risk factors of occupational skin diseases among traditional batik manufacturing workers in Yogyakarta, Indonesia

OBJECTIVE

Batik is one of the Indonesian traditional arts made by decorating fabric using the resist dyeing technique. Currently, batik manufacturing serves as an important source of livelihood in Indonesia. However, the production process of traditional batik involves a range of chemicals and some repetitive physical movements, making batik production inseparable from physical and chemical hazards which increase the risk of developing occupational skin diseases (OSD). This study aimed to identify the risk factors related to OSD, including occupational contact dermatitis (OCD), among traditional batik manufacturing workers in Yogyakarta, Indonesia.

RESULTS

The study demonstrated that working duration (≥ 8 h daily) and type of work (wet process only) were statistically significant as risk factors for developing OSD. While for OCD, our results found that gender (male), history of atopy, and type of work (all and wet phase only) were risk factors for OCD development among traditional batik manufacturing workers.

Contributions of renal water loss and skin water conservation to blood pressure elevation in spontaneously hypertensive rats

We recently reported that skin vasoconstriction to suppress transepidermal water loss (TEWL) leads to hypertension in renal injury model rats with impaired urine concentration ability. In this study, we investigated the pathogenesis of hypertension in spontaneously hypertensive rats (SHRs) from the perspective of renal water loss and skin water conservation. We compared the urinary concentration ability, body sodium and water balance, blood pressure, and TEWL in SHRs and control normotensive Wistar-Kyoto rats (WKYs). SHRs showed significantly higher urine volume and lower urinary osmolality than those of WKYs, while there were no significant differences in water intake, urinary osmolyte excretion, and plasma osmolarity between the groups. SHRs exhibited significantly higher blood pressure, skin sodium content, and lower TEWL compared with those is WKYs. Skin vasodilation, induced by elevating body temperature, increased TEWL in both SHRs and WKYs, and significantly reduced blood pressure in SHRs but not WKYs. These findings suggest that physiological adaptation can reduce dermal water loss in SHRs to compensate for renal water loss. Vasoconstriction required for successful cutaneous water conservation explains SHR hypertension. Renal concentration ability and skin barrier function for water conservation may become a novel therapeutic target for essential hypertension.

Menopause induces changes to the stratum corneum ceramide profile, which are prevented by hormone replacement therapy

The menopause can lead to epidermal changes that are alleviated by hormone replacement therapy (HRT). We hypothesise that these changes could relate to altered ceramide production, and that oestrogen may have a role in keratinocyte ceramide metabolism. White Caucasian women were recruited into three groups: pre-menopausal (n = 7), post-menopausal (n = 11) and post-menopausal taking HRT (n = 10). Blood samples were assessed for hormone levels, transepidermal water loss was measured to assess skin barrier function, and stratum corneum lipids were sampled from photoprotected buttock skin. Ceramides and sphingomyelins were analysed by ultraperformance liquid chromatography with electrospray ionisation and tandem mass spectrometry. Post-menopausal stratum corneum contained lower levels of ceramides, with shorter average length; changes that were not evident in the HRT group. Serum oestradiol correlated with ceramide abundance and length. Ceramides had shorter sphingoid bases, indicating altered de novo ceramide biosynthesis. Additionally, post-menopausal women had higher sphingomyelin levels, suggesting a possible effect on the hydrolysis pathway. Treatment of primary human keratinocytes with oestradiol (10 nM) increased production of CER[NS] and CER[NDS] ceramides, confirming an effect of oestrogen on cutaneous ceramide metabolism. Taken together, these data show perturbed stratum corneum lipids post-menopause, and a role for oestrogen in ceramide production.

Impacts of Skin Eccrine Glands on the Measured Values of Transepidermal Water Loss

Transepidermal water loss (TEWL) is widely used to assess and quantify skin insensible water loss to assess skin's barrier function integrity. Low TEWL values are normally indicative of intact skin and a healthy functional barrier, whereas an increased TEWL reveals a disturbed or disrupted skin barrier. Because most skin sites at which these measurements are made have eccrine glands present, the contribution of the sweat gland activity to these measurements is variable and, in most cases, unknown. The separation between the contribution of water loss that is reflective of the skin barrier integrity versus that contributed via eccrine activation is not easy and is made more difficult since both components increase with increasing skin and environmental temperature. Endogenous factors that impact eccrine sweat gland activity include sympathetic nervous system activity, emotional stress, physical activity, eccrine gland density, and age. Exogenous factors that impact eccrine gland activity include ambient temperature and humidity and the climate where one resides. The aforementioned variables impact eccrine gland activity positively or negatively and therefore alter TEWL values accordingly. Although it may be theoretically possible to control all these factors, the difficulty in doing so results in only a few being controlled during most TEWL measurements. Such confounding processes may have impacted historical TEWL reference ranges and values previously reported. Thus, the impact of eccrine activation on standardly measured TEWL values is at this juncture unclear and may be a component contributing to some reported variability in TEWL values. To help clarify the issues, a literature review was conducted to investigate and summarize relevant prior research efforts and outcomes with respect to ways to consider eccrine activity in TEWL measurements and estimate the contribution of eccrine gland activity to TEWL values. Online databases such as Excerpta Medica Database (EMBASE), Public/Publisher Medline (PubMed), Elton B. Stephans Company (EBSCO), Google Scholar, and Wiley Online Library were searched with "transepidermal water loss" or "TEWL" in the title combined with "eccrine glands" or "sweat" anywhere in the text. The present findings indicate a multiplicity of biological and environmental variables impacting eccrine gland activity and thereby potentially affecting measured TEWL values. Even if laboratory conditions adhere to various guidelines and recommendations, it is not yet possible to separate the eccrine activation component from the parameter of true interest in the assessment of the skin's physiological barrier function except for full gland deactivation. The amount that such eccrine gland activation impacts the measured value of TEWL is generally not determined using currently available methods and the only sure way to eliminate a confounding effect is to inactivate the glands during such TEWL measurements. Because such eccrine gland deactivating approach is not usually desirable or even possible, other approaches would be recommended. One would be the development of a measuring device that could distinguish between the component of TEWL that is associated with the skin barrier function and the other that is attributable to sweat gland activation. Further research and development along these lines appear warranted.

Effect of facial application of essence containing royal jelly extract on stratum corneum moisture content: A placebo-controlled, double-blind, parallel-group study

OBJECTIVES

To evaluate the moisturizing function and other effects of royal jelly extract on the skin. The effects of applying an essence containing royal jelly extract on the skin of healthy Japanese males and females were examined.

METHODS

Thirty-five healthy Japanese men and women who were aware of their skin dryness applied an essence containing royal jelly extract or placebo for 4 weeks using the split-face method in a placebo-controlled, double-blind, parallel comparative study. The stratum corneum water content, transepidermal water evaporation, pigmentation, pores, and redness were evaluated.

RESULTS

The stratum corneum water content significantly increased by the application of essence containing royal jelly extract to the cheeks for 4 weeks compared with placebo.

CONCLUSION

The application of an essence containing royal jelly extract significantly improved the moisture content of the stratum corneum of the cheeks, confirming the improvement in the moisturizing function of the royal jelly extract. Furthermore, no adverse events were observed at the application site during the application period, and the test products and royal jelly extract contained in the test product were considered highly safe.

The effect of pH-compatible cleansing cloths on skin pH and the development of pressure ulcers

AIM

Skin care plays an important role in the prevention of the development of pressure ulcers. The aim of this study was to determine the effect of skincare with a body pH-compatible cleansing cloth on the development time of pressure ulcers and on skin pH.

METHODS

This experimental research was conducted with 156 patients hospitalized in intensive care clinics of a state hospital between September 2019 and 2020. The sample was calculated with a power of 80% and a significance level of 0.05 (α error) and as a result, 78 elderly patients formed the intervention group and another 78 elderly patients made up the control group. Data were collected using the Elderly Information Form, Braden Risk Assessment Scale, Pressure Ulcer Staging Tool and Skin pH Measurement Form. The pre- and post-care skin pH of both groups was measured with a skin pH meter. P < 0.05 was considered statistically significant.

RESULTS

The average development time for pressure ulcers was 14.9 days in the control group, 18.9 days in the intervention group and the difference was not statistically significant (p > 0.05). Skin pH decreased in the intervention group after the skin care routine was applied, whereas it increased in the control group.

CONCLUSION

It can be said that care of one's skin with a body pH-compatible cleansing cloth has a positive effect on the development time of pressure ulcers and also positively changes the skin pH to acidic.

Effect of Rice (Oryza sativa L.) Ceramides Supplementation on Improving Skin Barrier Functions and Depigmentation: An Open-Label Prospective Study

Ceramides plays a crucial role in maintaining skin barrier function. Although foregoing evidence supported beneficial effects of topical ceramides for restoration of the skin barrier, studies on oral ceramides are extremely scarce, with most published data collected from in vivo and in vitro models. Thus, this study aimed to evaluate the efficacy of rice ceramides (RC) supplementation to improve skin barrier function and as a depigmenting agent through comprehensive clinical assessments. This study investigated the beneficial effects of orally administered RC supplementation in 50 voluntary participants. Skin hydration, firmness and elasticity, transepidermal water loss (TEWL), melanin index (MI), erythema index (EI), sebum production, pH, and wrinkle severity were assessed at baseline and during monthly follow-up visits. RC supplementation was found to significantly (p < 0.01) improve skin hydration, sebum production, firmness and elasticity, and wrinkle severity for three assessed areas, namely the left cheek, dorsal neck, and right inner forearm. Additionally, RC significantly (p < 0.01) reduced the rates of TEWL, levels of MI and EI. Analyses of data indicated that participants at older age were more responsive towards the effect of RC supplementation. Our findings suggest that RC supplementation can effectively improve skin barrier function, reduce wrinkle severity, and reduce pigmentation.

Molecular Mechanisms of Changes in Homeostasis of the Dermal Extracellular Matrix: Both Involutional and Mediated by Ultraviolet Radiation

Skin aging is a multi-factorial process that affects nearly every aspect of skin biology and function. With age, an impairment of structures, quality characteristics, and functions of the dermal extracellular matrix (ECM) occurs in the skin, which leads to disrupted functioning of dermal fibroblasts (DFs), the main cells supporting morphofunctional organization of the skin. The DF functioning directly depends on the state of the surrounding collagen matrix (CM). The intact collagen matrix ensures proper adhesion and mechanical tension in DFs, which allows these cells to maintain collagen homeostasis while ECM correctly regulates cellular processes. When the integrity of CM is destroyed, mechanotransduction is disrupted, which is accompanied by impairment of DF functioning and destruction of collagen homeostasis, thereby contributing to the progression of aging processes in skin tissues. This article considers in detail the processes of skin aging and associated changes in the skin layers, as well as the mechanisms of these processes at the molecular level.

Focus on the Contribution of Oxidative Stress in Skin Aging

Skin aging is one of the most evident signs of human aging. Modification of the skin during the life span is characterized by fine lines and wrinkling, loss of elasticity and volume, laxity, rough-textured appearance, and pallor. In contrast, photoaged skin is associated with uneven pigmentation (age spot) and is markedly wrinkled. At the cellular and molecular level, it consists of multiple interconnected processes based on biochemical reactions, genetic programs, and occurrence of external stimulation. The principal cellular perturbation in the skin driving senescence is the alteration of oxidative balance. In chronological aging, reactive oxygen species (ROS) are produced mainly through cellular oxidative metabolism during adenosine triphosphate (ATP) generation from glucose and mitochondrial dysfunction, whereas in extrinsic aging, loss of redox equilibrium is caused by environmental factors, such as ultraviolet radiation, pollution, cigarette smoking, and inadequate nutrition. During the aging process, oxidative stress is attributed to both augmented ROS production and reduced levels of enzymatic and non-enzymatic protectors. Apart from the evident appearance of structural change, throughout aging, the skin gradually loses its natural functional characteristics and regenerative potential. With aging, the skin immune system also undergoes functional senescence manifested as a reduced ability to counteract infections and augmented frequency of autoimmune and neoplastic diseases. This review proposes an update on the role of oxidative stress in the appearance of the clinical manifestation of skin aging, as well as of the molecular mechanisms that underline this natural phenomenon sometimes accelerated by external factors.

Newborn and elderly skin: two fragile skins at higher risk of pressure injury

Skin is a key organ maintaining internal homeostasis by performing many functions such as water loss prevention, body temperature regulation and protection from noxious substance absorption, microorganism intrusion and physical trauma. Skin ageing has been well studied and it is well known that physiological changes in the elderly result in higher skin fragility favouring the onset of skin diseases. For example, prolonged and/or high-intensity pressure may suppress local blood flow more easily, disturbing cell metabolism and inducing pressure injury (PI) formation. Pressure injuries (PIs) represent a significant problem worldwide and their prevalence remains too high. A higher PI prevalence is correlated with an elderly population. Newborn skin evolution has been less studied, but some data also report a higher PI prevalence in this population compared to older children, and several authors also consider this skin as physiologically fragile. In this review, we compare the characteristics of newborn and elderly skin in order to determine common features that may explain their fragility, especially regarding PI risk. We show that, despite differences in appearance, they share many common features leading to higher fragility to shear and pressure forces, not only at the structural level but also at the cellular and molecular level and in terms of physiology. Both newborn and elderly skin have: (i) a thinner epidermis; (ii) a thinner dermis containing a less-resistant collagen network, a higher collagen III:collagen I ratio and less elastin; (iii) a flatter dermal-epidermal junction (DEJ) with lower anchoring systems; and (iv) a thinner hypodermis, resulting in lower mechanical resistance to skin damage when pressure or shear forces are applied. At the molecular level, reduced expression of transforming growth factor β (TGFβ) and its receptor TGFβ receptor II (TβRII) is involved in the decreased production and/or increased degradation of various dermal extracellular matrix (ECM) components. Epidermal fragility also involves a higher skin pH which decreases the activity of key enzymes inducing ceramide deficiency and reduced barrier protection. This seems to be correlated with higher PI prevalence in some situations. Some data also suggest that stratum corneum (SC) dryness, which may disturb cell metabolism, also increases the risk of PI formation. Besides this structural fragility, several skin functions are also less efficient. Low applied pressures induce skin vessel vasodilation via a mechanism called pressure-induced vasodilation (PIV). Individuals lacking a normal PIV response show an early decrease in cutaneous blood flow in response to the application of very low pressures, reflecting vascular fragility of the skin that increases the risk of ulceration. Due to changes in endothelial function, skin PIV ability decreases during skin ageing, putting it at higher risk of PI formation. In newborns, some data lead us to hypothesize that the nitric oxide (NO) pathway is not fully functional at birth, which may partly explain the higher risk of PI formation in newborns. In the elderly, a lower PIV ability results from impaired functionality of skin innervation, in particular that of C-fibres which are involved in both touch and pain sensation and the PIV mechanism. In newborns, skin sensitivity differs from adults due to nerve system immaturity, but the role of this in PIV remains to be determined.

Facial Skin Aging Stages in Chinese Females

Background

Facial skin is exposed to the environment, which marks it with obvious signs of aging. Based on multi-dimensional non-invasive evaluation data, female facial skin can be characterized in detail. However, there are few studies on the general aging rules of facial skin. Most skin aging studies divide the ages into 5–10-year intervals, so they have lacked dynamic matching with facial skin aging.

Aim

To explore facial skin aging rules, discuss the main parameters of facial skin aging, propose an unequal-distance aging division method based on the main skin parameters, and study the skin characteristics of Chinese women of different aging stages.

Methods

We comprehensively described the skin status as 24 non-invasive skin parameters belonging to five dimensions: skin wrinkles, texture, stain, color and barrier function. We performed polynomial fitting on the 21 skin parameters that were significantly correlated with age and derived the rules of aging in the different dimensions. Based on the wrinkle dimension, the facial skin aging process was divided into four stages, and the skin characteristics of the different stages were compared.

Results

Skin wrinkles increased, texture deteriorated, acne decreased, pigment spots increased, skin tone darkened, and sebum secretion decreased with age, according to the polynomial fitting. The aging stage was divided into an incubation period (18–30 years old), an aging occurrence period (31–42 years old), a rapid aging period (43–47 years old), and a stable aging period (48–60 years old), according to the wrinkles. Different aging stages had different skin characteristics.

Conclusion

The incubation period is the critical period for the appearance of skin stains; the skin texture gradually deteriorates during the aging occurrence period; the rapid aging period is a critical period for the aging of skin parameters; skin status during the stable aging period is the worst.

Correlation of Body Mass Index with Epidermal Biophysical Properties Varies with Gender in Chinese

Background

Epidermal function is associated with diabetes and renal disease. Whether obesity can reflect the changes in epidermal function is not clear yet.

Objective

We assessed here the correlation of epidermal functions with body mass index (BMI) in a large Chinese cohort.

Methods and Subjects

A total of 1,405 Chinese aged 21–98 years old were enrolled in this study. Epidermal functions, including transepidermal water loss (TEWL), stratum corneum hydration, and skin surface pH, were measured on the flexor forearm and the shin. Subjects' height and body weight were also measured.

Results

Age positively correlated with both TEWL and skin surface pH, while it negatively correlated with stratum corneum hydration on both the forearm and the shin of females. Similarly, age positively correlated with skin surface pH, while negatively correlating with stratum corneum hydration on both the forearm and the shin of males. In females, BMI positively correlated with skin surface pH, while it negatively correlated with stratum corneum hydration on both the forearm and the shin. However, BMI correlated neither with skin surface pH on both the forearm and the shin nor with stratum corneum hydration on the shin of males.

Conclusion

These results demonstrate that correlations of BMI with age and epidermal functions vary with gender.

Molecular Mapping of Sebaceous Squalene by Ambient Mass Spectrometry

Squalene (SQ), a highly unsaturated sebaceous lipid, plays an important role in protecting human skin. To better understand the role of SQ in clinical medicine, an efficient analytical approach is needed to comprehensively study the distribution of SQ on different parts of the skin. In this study, sebaceous lipids were collected from different epidermal areas of a volunteer with sampling probes. Thermal desorption-electrospray ionization/mass spectrometry (TD-ESI/MS) was then used to characterize the lipid species on the probes, and each TD-ESI/MS analysis was completed within a few seconds without any sample pretreatment. The molecular mapping of epidermal squalene on whole-body skin was rendered by scaling the peak area of the extracted ion current (EIC) of SQ based on a temperature color gradient, where colors were assigned to the 1357 sampling locations on a 3D map of the volunteer. The image showed a higher SQ distribution on the face than any other area of the body, indicating the role of SQ in protecting facial skin. The results were in agreement with previous studies using SQ as a marker to explore sebaceous activity. The novelty and significance of this work are concluded as two points: (1) direct and rapid detection of all major classes of sebaceous lipids, including the unsaturated hydrocarbons (SQ) and nonpolar lipids (e.g., cholesterol). The results are unique compared to other conventional and ambient ionization mass spectrometry methods and (2) this is the first study to analyze SQ distribution on the whole-body skin by a high-throughput approach.

How good is the evidence that cellular senescence causes skin ageing?

Skin is the largest organ of the body with important protective functions, which become compromised with time due to both intrinsic and extrinsic ageing processes. Cellular senescence is the primary ageing process at cell level, associated with loss of proliferative capacity, mitochondrial dysfunction and significantly altered patterns of expression and secretion of bioactive molecules. Intervention experiments have proven cell senescence as a relevant cause of ageing in many organs. In case of skin, accumulation of senescence in all major compartments with ageing is well documented and might be responsible for most, if not all, the molecular changes observed during ageing. Incorporation of senescent cells into in-vitro skin models (specifically 3D full thickness models) recapitulates changes typically associated with skin ageing. However, crucial evidence is still missing. A beneficial effect of senescent cell ablation on skin ageing has so far only been shown following rather unspecific interventions or in transgenic mouse models. We conclude that evidence for cellular senescence as a relevant cause of intrinsic skin ageing is highly suggestive but not yet completely conclusive.

Transdermal anti-inflammatory therapy for aqueous deficiency

PURPOSE

Lacrimal gland inflammation has been identified as an important limitation on aqueous production and associated dry eye disease. Ocular surface inflammation in dry eye disease can be a downstream response to reduced quantities of warmer hyperosmotic aqueous being delivered from an inflamed lacrimal gland with high concentrations of inflammatory mediators. This review examines evidence which shows how topical applications of anti-inflammatory drugs have very limited access to the lacrimal gland and an associated limited capacity to increase aqueous flow by reducing inflammation in the main lacrimal gland.

RECENT FINDINGS

Using cyclosporine as an exemplar immunomodulatory drug, this review examines problems associated with the topical administration of all anti-inflammatory drugs in the treatment of dry eye disease.

SUMMARY

Limited access to the lacrimal gland for topical applications and their very short on-eye residence times are compared with the therapeutic potential of prolonged therapeutic episodes that could be achieved with transdermal applications of a drug to the skin at the site of the lacrimal gland. Poor access to the lacrimal gland for topically administered drugs is a major barrier to the treatment of aqueous deficiency. While topical inflammatory drug access to the ocular surface is direct, poor access to the lacrimal gland is partly due to drop placement being downstream to the flow of aqueous (Eye Vis 2020;7:1; Eye Vis 2019;6:1). This barrier is much greater according to the degree that reflex tear flow is stimulated by irritation associated with adverse drop temperature, and/or pH and/or tonicity for example.

Towards Optimal pH of the Skin and Topical Formulations: From the Current State of the Art to Tailored Products

Acidic pH of the skin surface has been recognized as a regulating factor for the maintenance of the stratum corneum homeostasis and barrier permeability. The most important functions of acidic pH seem to be related to the keratinocyte differentiation process, the formation and function of epidermal lipids and the corneocyte lipid envelope, the maintenance of the skin microbiome and, consequently, skin disturbances and diseases. As acknowledged extrinsic factors that affect skin pH, topically applied products could contribute to skin health maintenance via skin pH value control. The obtained knowledge on skins’ pH could be used in the formulation of more effective topical products, which would add to the development of the so-called products ‘for skin health maintenance’. There is a high level of agreement that topical products should be acidified and possess pH in the range of 4 to 6. However, formulators, dermatologists and consumers would benefit from some more precise guidance concerning favorable products pH values and the selection of cosmetic ingredients which could be responsible for acidification, together with a more extensive understanding of the mechanisms underlaying the process of skin acidification by topical products.

Algae as an attractive source for cosmetics to counter environmental stress

In recent times, a considerable amount of evidence has come to light regarding the effect that air pollution has on skin conditions. The human skin is the chief protection we have against environmental harm, whether biological, chemical, or physical. The stress from these environmental factors, along with internal influences, can be a cause of skin aging and enlarged pores, thinner skin, skin laxity, wrinkles, fine lines, dryness, and a more fragile dermal layer. This knowledge has led to greater demand for skin cosmetics and a requirement for natural raw ingredients with a high degree of safety and efficiency in combating skin complications. Recent developments in green technology have made the employment of naturally occurring bioactive compounds more popular, and novel extraction methods have ensured that the use of these compounds has greater compatibility with sustainable development principles. Thus, there is a demand for investigations into efficient non-harmful naturally occurring raw ingredients; compounds derived from algae could be beneficial in this area. Algae, both macroalgae and microalgae, consists of waterborne photosynthetic organisms that are potentially valuable as they have a range of bioactive compounds in their composition. Several beneficial metabolites can be obtained from algae, such as antioxidants, carotenoids, mycosporine-like amino acids (MAA), pigments, polysaccharides, and scytonemin. Various algae strains are now widely employed in skincare products for various purposes, such as a moisturizer, anti-wrinkle agent, texture-enhancing agents, or sunscreen. This research considers the environmental stresses on human skin and how they may be mitigated using cosmetics created using algae; special attention will be paid to external factors, both generally and specifically (amongst them light exposure and pollutants).

Formulation of topical acidic products and acidification of the skin - Contribution of glycolic acid

OBJECTIVE

The acidic skin pH is one of the regulating factors of skin barrier homeostasis. Topical products as extrinsic factors which influence skin pH could be used for acidification of the skin and consequent beneficial effect. To formulate stabile and safe topical emulsion product with low pH is on-going challenge and areas interesting to explore are related to the effect of acidic products on the skin pH together with development of protocols for these studies. Aim of our work was to investigate formulations of acidic topical products with glycolic acid (GA) stabilized with long chain alkyl polyglucoside emulsifier, in regard to the specific colloidal structure of the vehicle, together with effect of products with different concentration of acidic active on skin pH.

METHODS

Investigated formulations were basic vehicle and two creams with glycolic acid (concentration 2 and 10 wt%). Microstructure was investigated by polarization microscopy, Raman spectral imaging, thermal analysis and rheological measurements. Effects on the skin were assessed by measurement of biophysical skin parameters in vivo studies (5-hour, 24-hour and 7-days). In vitro screening of antimicrobial activity was performed against bacteria Staphylococcus epidermidis.

RESULTS

Polarization micrographs and Raman images have shown that GA does not disturb the specific colloidal structure. Together with rheological and thermal analysis obtained results have shown that GA in higher concentrations contributes to vehicles' lamellar structure. In 5-hour study the mean values of skin pH ranged from 3.98-4.25 and 3.89-4.10 after application of products with smaller and higher GA concentration. GA samples lowered skin surface pH to 5 and less in 24-hour and 7-day study, with stronger effect of sample with more GA. Sample with 10% of GA had significant inhibitory effect on growth of S. epidermidis in 1:1 concentration.

CONCLUSIONS

Investigated APG emulsifier could be used as a stabilizer for acidic topical products with GA which are characterized by satisfactory safety profile. Topical products induce acidification of the skin after short- and long-term application without barrier impairment or sign of irritation. Acidification of the skin depends on presence of ingredients which are proton donors and their concentrations.

Effects of Exercise on the Skin Epithelial Barrier of Young Elite Athletes-Swimming Comparatively to Non-Water Sports Training Session

The benefits of swimming have been extensively assessed. However, swimming pools contain chlorine and other irritating chemicals that may induce contact dermatitis. To evaluate the effect of a swimming training session on transepidermal water loss (TWEL) in swimmers compared to football players, elite swimmers and football players were invited to participate (58 athletes) in the study, where TEWL was measured before, immediately after, and 30 min after a 2 h training session. The probe was held on the dorsum of the hand, volar forearm, and on the antecubital flexure for 1 min. The volar forearm, antecubital flexure, and hand dorsum showed a significant increase in TEWL in swimmers in both measurements after training compared to baseline (p < 0.001). In football players, an increase in TEWL was observed on the hands' dorsum between baseline and after training measurements. The variations on TEWL levels before and immediately after the training session were higher among swimmers on the volar forearm (p = 0.002) and antecubital flexure (p = 0.019). Our findings support the effect of the training environment-swimming pool versus outdoor sports-on the skin barrier function, with an increase of transepidermal water loss immediately after exercise. Exposure to a swimming pool environment in a 2 h training session may lead to changes in skin barrier function.

Statistical analysis of age-related skin parameters

BACKGROUND

Due to the increasing interest in human anti-aging, demand for a higher quality of life, and technological advancement, the development of anti-aging skincare has great market prospects. Most cosmetic companies develop products driven by the market or focus on the mechanism of action of substances and the behavior of skin; however, little research utilizes skin parameters and large data methodology to develop skincare products.

OBJECTIVE

To instruct consumers to purchase skincare products and to guide skincare research toward the development of customer-targeted products.

METHODS

A total of 815 Chinese subjects (83 male; 732 female) from five different cities were included. We measured 14 indices in each subject, including moisture, transepidermal water loss (TEWL), and sebum levels. We performed multiple regression analysis to understand the relationship between skin indices and aging; a novel approach is shown using the R software.

RESULTS

The exact age at which changes in each skin index occurred could be demonstrated by this method of analysis: 39, 38, 48, 46, and 56 years old with respect to the L value, Melanin, Rt, Rm, and Rz, respectively.

CONCLUSION

With the use of statistical analysis, consumers can be more efficiently targeted and choose suitable products considering particular skin parameter changing points; thus, skincare companies will not only meet customer requirements but also better control budgets.

The Interaction of Age and Anatomical Region Influenced Skin Biophysical Characteristics of Chinese Women

BACKGROUND

Ageing is an inevitable physiology process of humans, and skin biophysical parameters change owing to genetic and environmental factors in different ethnic populations.

AIM

To gain comprehensive data on the skin biophysical parameters of different anatomical regions and to explore the change trend of the skin characteristics associated with age for the indicated regions by generalized additive model.

METHODS

We measured various skin biophysical parameters on forehead, cheek, chin and inner forearm of 178 Chinese women aged between 20 and 64 years living in Beijing. These parameters comprised skin hydration, transepidermal water loss (TEWL), sebum content, erythema index (EI), melanin index (MI), L*a*b* values, individual typology angle (ITA) and pH, which were quantified by non-invasive instruments.

RESULTS

Comparing the skin parameters among the four test areas, we observed that the hydration, TEWL, EI and a* values were significantly higher for the face than for the forearm, but the L* and ITA values were just the opposite. The cheek was the lightest and brightest region with lowest sebum content, while the chin was much darker and the forehead was yellowish. Considering the change of the skin parameters with age, TEWL, sebum content and melanin and erythema indices had a linear relationship with age, whereas skin hydration, L, a, b, ITA and pH values exhibited a non-monotonic relationship. The turning points of these curves appeared almost at the thirties, showing the lightest and evenest skin color and more hydration, with lower pH values.

CONCLUSION

This study indicates that the skin biophysical characteristics of Chinese women were significantly affected by age and body regions.

Stability of Skin Microbiome at Sacral Regions of Healthy Young Adults, Ambulatory Older Adults, and Bedridden Older Patients After 2 Years

OBJECTIVE

The sacral skin of bedridden older patients often develops a dysbiotic condition. To clarify whether the condition changes or is sustained over time, we analyzed the skin microbiome and the skin physiological functions of the sacral skin in patients who completed our 2017 study.

METHODS

In 2019, we collected the microbiome on the sacral region and measured sacral skin hydration, pH, and transepidermal water loss from 7 healthy young adults, 10 ambulatory older adults, and 8 bedridden older patients, all of whom had been recruited for the 2017 study. For microbiome analysis, 16S ribosomal RNA-based metagenomic analysis was used.

RESULTS

No significant differences in the microbial compositions or any alpha diversity metrics were found in the bedridden older patients between the 2017 and 2019 studies; the higher gut-related bacteria were still observed on the sacral skin of the bedridden older patients even after 2 years. Only skin pH showed a significant decrease, approaching normal skin condition, in the bedridden older patients over 2 years.

CONCLUSION

This study indicated that gut-related bacteria stably resided in the sacral skin in bedridden patients, even if the patient had tried to restore skin physiological functions using daily skin care. We propose the importance of skin care that focuses more on bacterial decontamination for the sacral region of bedridden older patients, in order to decrease the chances of skin/wound infection and inflammation.

Purple tulip extract improves signs of skin aging through dermal structural modulation as shown by genomic, protein expression and skin appearance of volunteers studied

BACKGROUND

Purple tulip extract is a rich source of flavonoids which are powerful antioxidants and can hence be considered as an ideal candidate for use in skin care products.

AIMS

We aimed to evaluate the effects of purple tulip extract on skin quality and to determine its molecular modes of interaction.

METHODS

A pangenomic study on human skin fibroblasts was carried out to analyze multiple changes in gene expression. Ex vivo studies of human skin explants exposed to ultraviolet (UV) irradiation or H₂ O₂ were performed to assess modulations of protein expression. Finally, a clinical assay was carried out to evaluate the efficacy of purple tulip extract on skin appearance and condition of aged women.

RESULTS

Genetic modulation analyses led us to infer the induction of many biological functions including cell differentiation, proliferation, migration, inflammatory responses, and matrix remodeling. The ex vivo studies revealed an enhancement of the collagen network and increased expression of glycosaminoglycans (GAG), fibronectin, and collagen VI. Finally, the clinical study highlighted the potential anti-aging properties of the purple tulip extract which decreased the relaxation of the oval face and improved skin elasticity after 28 days of treatment. Significant reductions of the length and depth of the nasolabial wrinkles were also observed.

CONCLUSION

Our genomics data on the effect of purple tulip extract on the ex vivo UV-challenged skin showed that genes responsible for, among others, the upkeep of the skin, such as collagen induction, immune cell proliferation, and epidermal repair, were all up-regulated. More importantly, the clinical study corroborated these data by the visible and measurable effects of the topical purple tulip extract on the aged skin of 22 women, further demonstrating the beneficial impact of the extract on aged skin.

Aloe barbadensis: A Plant of Nutricosmetic Interest

Aloe barbadensis Miller (Aloe Vera Linne) products have long been employed in health foods and for medical purposes. It has anti-inflammatory, antifungal, antioxidant properties, which indicates excellent potential in antiaging cosmetic and skin protection products. The objective of this study is to evaluate the antiaging efficacy of dermocosmetic formulations containing A. barbadensis extract on young and mature skin using biophysical and skin imaging techniques. Twenty healthy adult volunteers participated in the study, aged between 20 and 65. The cream formulation, with 10% (w/w) of A. barbadensis extract, and placebo, were applied to the face of the volunteers. The effects were evaluated in terms of skin hydration and barrier effect by the measurement of transepidermal water loss (TEWL), derma firmness, and elasticity. The formulation containing A. barbadensis extract significantly improves water contained in the stratum corneum, firmness, elasticity of the skin, and decreased TEWL.

Alterations in extracellular matrix composition during aging and photoaging of the skin

Human skin is composed of the cell-rich epidermis, the extracellular matrix (ECM) rich dermis, and the hypodermis. Within the dermis, a dense network of ECM proteins provides structural support to the skin and regulates a wide variety of signaling pathways which govern cell proliferation and other critical processes. Both intrinsic aging, which occurs steadily over time, and extrinsic aging (photoaging), which occurs as a result of external insults such as solar radiation, cause alterations to the dermal ECM. In this study, we utilized both quantitative and global proteomics, alongside single harmonic generation (SHG) and two-photon autofluorescence (TPAF) imaging, to assess changes in dermal composition during intrinsic and extrinsic aging. We find that both intrinsic and extrinsic aging result in significant decreases in ECM-supporting proteoglycans and structural ECM integrity, evidenced by decreasing collagen abundance and increasing fibril fragmentation. Intrinsic aging also produces changes distinct from those produced by photoaging, including reductions in elastic fiber and crosslinking enzyme abundance. In contrast, photoaging is primarily defined by increases in elastic fiber-associated protein and pro-inflammatory proteases. Changes associated with photoaging are evident even in young (mid 20s) sun-exposed forearm skin, indicating that proteomic evidence of photoaging is present decades prior to clinical signs of photoaging. GO term enrichment revealed that both intrinsic aging and photoaging share common features of chronic inflammation. The proteomic data has been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier PXD015982.

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Intrinsic aging and photoaging both decrease ECM-supporting proteoglycans and structural ECM.

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Intrinsic aging produces reductions in elastic fiber and crosslinking enzyme abundance.

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Photoaging results in increases in pro-inflammatory proteases and elastic fiber abundance.

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Intrinsic aging and photoaging share common features associated with chronic inflammation.

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Proteomic changes associated with photoaging are evident decades prior to clinical aging signs.

Shedding Light on the Effects of Calorie Restriction and its Mimetics on Skin Biology

During the aging process of an organism, the skin gradually loses its structural and functional characteristics. The skin becomes more fragile and vulnerable to damage, which may contribute to age-related diseases and even death. Skin aging is aggravated by the fact that the skin is in direct contact with extrinsic factors, such as ultraviolet irradiation. While calorie restriction (CR) is the most effective intervention to extend the lifespan of organisms and prevent age-related disorders, its effects on cutaneous aging and disorders are poorly understood. This review discusses the effects of CR and its alternative dietary intake on skin biology, with a focus on skin aging. CR structurally and functionally affects most of the skin and has been reported to rescue both age-related and photo-induced changes. The anti-inflammatory, anti-oxidative, stem cell maintenance, and metabolic activities of CR contribute to its beneficial effects on the skin. To the best of the author’s knowledge, the effects of fasting or a specific nutrient-restricted diet on skin aging have not been evaluated; these strategies offer benefits in wound healing and inflammatory skin diseases. In addition, well-known CR mimetics, including resveratrol, metformin, rapamycin, and peroxisome proliferator-activated receptor agonists, show CR-like prevention against skin aging. An overview of the role of CR in skin biology will provide valuable insights that would eventually lead to improvements in skin health.

Distinct Skin Microbiome and Skin Physiological Functions Between Bedridden Older Patients and Healthy People: A Single-Center Study in Japan

With the increase in the older populations, the number of bedridden older patients is becoming a matter of concern. Skin microbiome and skin physiological functions are known to change according to lifestyle and community; however, such changes in case of movement- and cleaning-restricted bedridden older patients have not yet been revealed. To address this issue, we analyzed skin microbiome and skin physiological functions, including pH, hydration, sebum level, and transepidermal water loss (TEWL), of bedridden older patients, compared with those of ambulatory older and young individuals. For this analysis, we enrolled 19 healthy young and 18 ambulatory older individuals from the community and 31 bedridden older patients from a single, long-term care hospital in Japan. The area of interest was set to the sacral (lower back) skin, where pressure injuries (PIs) and subsequent infection frequently occurs in bedridden older patients. We observed a higher number of gut-related bacteria, fewer commensals, higher skin pH, and lower TEWL on the sacral skin of bedridden older patients than on that of young or ambulatory older individuals. In addition, we observed that 4 of the 31 bedridden older patients developed PIs during the research period; a higher abundance of pathogenic skin bacteria were also observed inside the PI wounds. These findings imply distinct skin microbiome and skin physiological functions in bedridden older patients in comparison with healthy individuals and may suggest the need for more stringent cleaning of the skin of bedridden older patients in light of the closeness of skin and wound microbiome.

Aging-associated alterations in epidermal function and their clinical significance

Chronologically-aged skin displays multiple functional changes in both the dermis and the epidermis. It appears that epidermal dysfunction, compromised permeability homeostasis, reduced stratum corneum hydration and elevated skin surface pH predispose to the development of aging-associated cutaneous and extracutaneous disorders. Improvements in epidermal function have been shown to be an effective alternative therapy in the prevention and treatment of some aging-associated cutaneous disorders, including eczematous dermatitis, pruritus, and xerosis. Recent studies demonstrated that epidermal dysfunction leads to the development of chronic, low-grade systemic inflammation, termed ‘inflammaging,’ which is linked to the development of aging-associated systemic disorders. Thus, correction of epidermal dysfunction could comprise a novel strategy in the prevention and treatment of aging-associated systemic disorders as well. In this review, we summarize aging-associated alterations in epidermal function, their underlying mechanisms, and their clinical significance. Regimens to improve epidermal function in the elderly are also discussed.

In vitro and in vivo evaluation of a moisture treatment cream containing three critical elements of natural skin moisturization

Objectives

To evaluate skin barrier and hydration effects of a new rebalancing moisture treatment (TRMT) and to assess efficacy and tolerability in subjects with photodamaged skin.

Methods

In an epidermal skin model, tissues (n = 5/group) were topically treated with 25 µL of TRMT, 25 µL of a market‐leading moisturizer (MLM), or untreated for 60 minutes. Hydration was measured at 0, 15, and 30 minutes. Tissues were harvested for gene expression analysis of markers associated with skin barrier and hydration: Claudin (CLD), Aquaporin (AQP), Hyaluronic Acid Syntheses (HAS), and Hyaluronidase (HYAL). A clinical study evaluated twice‐daily application of TRMT, assessing changes in fine lines/wrinkles, brightness, texture, erythema, and tolerability from baseline through week 8. Hydration was measured using electrical impedance.

Results

TRMT and MLM demonstrated significant increases in hydration vs untreated tissue at each timepoint (P < .005), with greater hydration effects observed for TRMT vs MLM. TRMT‐treated tissues demonstrated greater expression of CLD, AQP, and HA, and reduced expression of HYAL vs untreated and MLM‐treated tissues. Twice‐daily application of TRMT demonstrated significant improvements at 2 weeks in fine lines/wrinkles (P < .001), brightness (P < .0001), texture (P < .0004), and hydration (P < .004). At 8 weeks, statistically significant improvements were achieved in all categories.

Conclusion

In an epidermal skin model, TRMT demonstrated significant increases in hydration, greater hydration effects, and expression of key markers associated with skin barrier and hydration vs a MLM. Twice‐daily application of TRMT was well tolerated and resulted in early, significant improvements in hydration and visible improvements in skin brightness, texture, fine lines/wrinkles, and erythema at 8 weeks.

Effects of differences in wiping pressure applied by nurses during daily bed baths on skin barrier function, cleanliness, and subjective evaluations

AIM

To clarify the actual condition and examine the effects of differences in wiping pressure applied by clinical nurses during daily bed baths on skin barrier function, cleanliness, and subjective evaluations.

METHODS

For the purposes of the present quasi-experimental interventional study, "wiping pressure" was defined as the "force applied vertically to the skin surface during bed baths." Two types of bed baths, one using ordinary wiping (pressure: 23-25 mmHg) and the other using weak wiping (pressure: 12-14 mmHg), were performed on the forearms (right and left) of 30 healthy adult men and women, and the effects on transepidermal water loss, stratum corneum hydration, cleanliness, and subjective evaluations were examined.

RESULTS

The results showed no differences between ordinary and weak wiping pressure in regard to the effects on skin barrier function and cleanliness. In terms of subjective evaluations, a significant association was seen between wiping pressure and the "sensation of having dirt removed" (P = .036). Regarding "degree of pain," some participants reported that the wiping pressure felt "slightly painful" under both conditions (ordinary: 31.1%; weak: 10.7%), while some with sensitive skin reported feeling pain even during weak wiping pressure.

CONCLUSIONS

The results of the present study suggest that skin assessments should be performed before and after bed baths, and that wiping pressure should be controlled and evaluated while considering the patient's feelings.

Management of Itch in the Elderly: A Review

Chronic itch is common in the elderly patient and may be caused by a variety of known dermatologic and non-dermatologic conditions and can have a significant effect on quality of life. Age-related changes in barrier function, immunosenescence, and neuronal changes and neuropathies are common predisposing factors to chronic itch in this age group. Certain primary dermatologic conditions are more common in the elderly and can cause chronic itch. Also, co-morbid diseases particularly of the renal, hepatobiliary, or hematologic systems, psychologic conditions, or medications may contribute to chronic itch in this population. Thus, medical workup for an elderly patient with chronic itch requires special attention to the patient's medical history, current health status, and medications. Topical treatments and emollients may be recommended for elderly patients, with consideration of specific adverse effects and alternatives. Systemic medications pose a higher risk of adverse effects and many are contraindicated in the elderly for this reason. In addition, management in the elderly may be complicated by differential pharmacokinetics of medications, the presence of co-morbid health conditions, cognitive disorders, physical limitations, and polypharmacy. New and emerging treatment modalities hold promise for use in the elderly due to these special considerations.

Atopic dermatitis in the elderly: a review of clinical and pathophysiological hallmarks

BACKGROUND

Atopic dermatitis (AD) is a multifactorial and complex disease, characterized by an impaired skin barrier function and abnormal immune response. Many elderly patients present with pruritus and xerosis to dermatology, allergy and primary care clinics, and there is a lack of information available to clinicians regarding the proper diagnosis and management of these patients. Although the elderly are described as having a distinct presentation of AD and important comorbidities, most investigations and clinical care guidelines pertaining to AD do not include patients aged 60 years and older as a separate group from younger adults.

OBJECTIVES

To summarize current information on pathophysiology, diagnosis and management of AD in the elderly population and identify areas of insufficient information to be explored in future investigations.

METHODS

We carried out a systematic review of published literature, which assessed changes in the skin barrier and immune function with ageing and current information available for physicians to use in the diagnosis and treatment of AD in elderly patients.

RESULTS

Many age-related changes overlap with key hallmarks observed in AD, most notably a decline in skin barrier function, dysregulation of the innate immune system, and skewing of adaptive immunity to a type-2 T helper cell response, in addition to increased Staphylococcus aureus infection.

CONCLUSIONS

While general physiological alterations with ageing overlap with key features of AD, a research gap exists regarding specific ageing-related changes in AD disease development. More knowledge about AD in the elderly is needed to establish firm diagnostic and treatment methodologies. What's already known about this topic? Atopic dermatitis (AD) is a common inflammatory skin disease that causes significant burden worldwide. Recently, elderly patients have been considered a subgroup of patients with distinct AD manifestation. Limited studies have characterized the clinical presentation and role of IgE-mediated allergy in elderly patients with AD. What does this study add? This review offers a summary of age-related skin and immune alterations that correspond to pathogenic changes noted in patients with AD. The role of itch, environmental factors and skin microbiota in AD disease presentation in ageing patients is explored.

Wild-type and SAMP8 mice show age-dependent changes in distinct stem cell compartments of the interfollicular epidermis

Delayed wound healing and reduced barrier function with an increased risk of cancer are characteristics of aged skin and one possible mechanism is misregulation or dysfunction of epidermal stem cells during aging. Recent studies have identified heterogeneous stem cell populations within the mouse interfollicular epidermis that are defined by territorial distribution and cell division frequency; however, it is unknown whether the individual stem cell populations undergo distinct aging processes. Here we provide comprehensive characterization of age-related changes in the mouse epidermis within the specific territories of slow-cycling and fast-dividing stem cells using old wild-type, senescence-accelerated mouse prone 1 (SAMP1) and SAMP8 mice. During aging, the epidermis exhibits structural changes such as irregular micro-undulations and overall thinning of the tissue. We also find that, in the old epidermis, proliferation is preferentially decreased in the region where fast-dividing stem cells reside whereas the lineage differentiation marker appears to be more affected in the slow-cycling stem cell region. Furthermore, SAMP8, but not SAMP1, exhibits precocious aging similar to that of aged wild-type mice, suggesting a potential use of this model for aging study of the epidermis and its stem cells. Taken together, our study reveals distinct aging processes governing the two epidermal stem cell populations and suggests a potential mechanism in differential responses of compartmentalized stem cells and their niches to aging.

Physiologically based pharmacokinetic modelling to guide drug delivery in older people

Older patients are generally not included in Phase 1 clinical trials despite being the population group who use the largest number of prescription medicines. Physiologically based pharmacokinetic (PBPK) modelling provides an understanding of the absorption and disposition of drugs in older patients. In this review, PBPK models used for the prediction of absorption and exposure of drugs after parenteral, oral and transdermal administration are discussed. Comparisons between predicted drug pharmacokinetics (PK) and observed PK are presented to illustrate the accuracy of the predictions by the PBPK models and their potential use in informing clinical trial design and dosage adjustments in older patients. In addition, a case of PBPK modelling of a bioequivalence study on two controlled release products is described, where PBPK predictions reproduced the study showing bioequivalence in healthy volunteers but not in older subjects with achlorhydria, indicating further utility in prospectively identifying challenges in bioequivalence studies.