Influence of age and regional differences on skin elasticity as measured by the Cutometer®

Background/aim: Aging of skin is accompanied by decrease of skin elasticity. Using the noninvasive suction device Cutometer^®, we evaluated the age and regional body differences of the viscoelastic properties of human skin. The objectives of this study were to evaluate the correlation between age and the biomechanical parameters and the regional skin variations.
Methods: A total of 96 healthy women aged 20–75 years were included in this study. The biomechanical properties of the skin were measured by using the Cutometer^®. Measurements were made on the face, upper arm and back.
Results: The age of subjects showed significant positive correlation with R4 and R6, and negative correlation with R2, R5 and R7. The face showed bigger changes of elastic properties than the arm and the back. Especially, the R7 of face was most significantly decreased with aging. We could estimate the so-called 'skin age' by using a correlation equation for this parameter.
Conclusion: The viscoelastic properties were significantly influenced by aging. Also, significant regional variations in the viscoelastic properties were observed. Skin elasticity measurement is useful for the quantitative evaluation of age-related changes.     

Effects of microdermabrasion on skin rejuvenation

Abstract

Background: Microdermabrasion is a surface treatment, noninvasive, which uses a negative pressure and drives programmable inert microcrystals on the skin, causing an exfoliation. Objective: The aim of this study was to evaluate the effects of application of microdermabrasion in human skin rejuvenation. Methods: Eleven women who were undergoing abdominoplasty were considered. An area of 25 cm² in the umbilicus to the right was conditioned with microcrystals of Al₂O₃ in maximum flow, negative pressure of 200 mmHg and total of 8 past, the left side being used as control. The number of sessions ranged from one to five, with weekly intervals, and timing of sample collection ranged from 0 to 132 days. Samples were fixed in 10% formaldehyde in phosphate buffer and were evaluated histologically. Results: A mild to marked hyperpigmentation was observed and remained for a variable period. Histological findings suggest an improvement in the epidermal layer with increased thickness and reestablishing their interdigitations in the dermis initially observed an increase in collagen synthesis. The analysis showed a late stay of epidermal changes, which did not occur in the dermis. Conclusion: Under the conditions and parameters used in this work, the microdermabrasion had a positive skin structure, showing that a viable resource in promoting skin rejuvenation.     

A study on the delayed effect of tilapia skin collagen on skin aging for mice and its possible mechanism

Objective

Study the possible mechanism and delayed effect of tilapia skin collagen on skin aging for mice.

Materials and Methods

Kunming (KM) mice were randomly divided into the aging model group, the normal group, the positive control group (vitamin E) and the low, medium, high dose tilapia skin collagen groups (2.0, 4.0, 8.0 mg/g). The normal group was only injected with saline at the back and the neck. The other groups were injected subcutaneously with 5% D-galactose and ultraviolet light jointly to establish the aging model. After modeling, the positive control group was treated with a dose of 10% vitamin E once a day, and the low, medium, high dose tilapia skin collagen group was separately applied 2.0, 4.0, 8.0 mg/g of tilapia skin collagen for 40 days. The changes of skin tissue morphology, water content, hydroxyproline (Hyp) content, and superoxide dismutase (SOD) activity in mice were studied at the day 10, 20, 30, 40, 50.

Results

Compared with the normal group, the skin of mice in the aging model group was thinner, looser, and the skin moisture content, Hyp content, SOD activity were all decreased. For mice of the low, medium, high dose tilapia skin collagen group, the thickness of dermis increased, possessing close arrangement, and the moisture content, Hyp content, SOD activity were up-regulated significantly, which effectively alleviated the aging process of skin. The dose of tilapia skin collagen was directly proportional to the anti-aging effect.

Conclusions

Tilapia skin collagen has an obvious effect on improving skin aging.     

Biology of estrogens in skin: implications for skin aging

Estrogens have a profound influence on skin. The relative hypoestrogenism that accompanies menopause exacerbates the deleterious effects of both intrinsic and environmental aging. Estrogens clearly have a key role in skin aging homeostasis as evidenced by the accelerated decline in skin appearance seen in the perimenopausal years. Estrogens improve skin in many ways. Among these, they increase collagen content and skin thickness and improve skin moisture. However, despite the knowledge that estrogens have such important effects on skin, the cellular and subcellular sites and mechanisms of estrogen action are still poorly understood. Estrogen receptors (ERs) have been detected in skin, and recent studies suggest that estrogens exert their effect in skin through the same molecular pathways used in other non-reproductive tissues. Although systemic hormone replacement therapy (HRT) has been used for many years, recent trials have reported a significant increased risk of breast cancer and other pathologies with this treatment. This has led to reconsider the risks and benefits of HRT. For this reason, systemic HRT cannot be recommended today to treat skin aging. Currently, intensive research is conducted to develop new drugs called selective ER modulators (SERMs). These drugs exert mixed estrogenic and antiestrogenic effects depending on the tissue and cell type. One might expect in the future such a drug targeting specifically the skin without systemic side effects.     

Evaluation of effects of platelet-rich plasma on human facial skin

Abstract

Introduction: Platelet-rich plasma (PRP) has been used for rapid healing and tissue regeneration in many fields of medicine. This study was conducted to evaluate the effects of PRP application procedure on human facial skin. Methods: PRP was applied thrice at 2-week intervals on the face of ten healthy volunteers. It was applied to individual's forehead, malar area, and jaw by a dermaroller, and injected using a 27-gauge injector into the wrinkles of crow's feet. Participants were asked to grade on a scale from 0 to 5 for general appearance, skin firmness–sagging, wrinkle state and pigmentation disorder of their own face before each PRP procedure and 3 months after the last PRP procedure. While volunteers were evaluating their own face, they were also assessed by three different dermatologists at the same time by the same five-point scale. Results: There was statistically significant difference regarding the general appearance, skin firmness-sagging and wrinkle state according to the grading scale of the patients before and after three PRP applications. Whereas there was only statistically significant difference for the skin firmness–sagging according to the assessment of the dermatologists. Conclusion: PRP application could be considered as an effective procedure for facial skin rejuvenation.     

Local tissue water assessed by measuring forearm skin dielectric constant: dependence on measurement depth, age and body mass index

Background: Tissue dielectric constant (TDC) measured at 300 MHz via the coaxial line reflection method is useful to evaluate local tissue water (LTW) and its change. Because excitation field penetration depth depends on size and geometry of the coaxial probe in contact with the skin, TDC values reflect skin and subcutaneous fat to varying depths depending on the probe used. Because tissue changes that occur with age or body mass index (BMI) may affect tissue water content and its depth distribution, our goal was to use TDC measurements to characterize depth patterns of LTW in normal tissue and to investigate the possible impact of age and BMI.
Methods: TDC was measured to depths of 0.5, 1.5, 2.5 and 5.0 mm on both forearms of 69 healthy women (age: 22–82 years, BMI: 18.7–46.1 kg/m²).
Results: Independent of age or BMI, TDC values decreased significantly with increasing measurement depth (33.7±5.8 at 0.5 mm to 21.8±3.7 at 5.0 mm) but at all depths dominant and non-dominant TDC values were similar to each other with ratios ranging from 1.025±0.081 at 0.5 mm to 1.017±0.097 at 5.0 mm. TDC values only at 2.5 and 5.0 mm decreased significantly with increasing BMI whereas TDC values only at 0.5 and 1.5 mm increased significantly with age.
Conclusion: The findings indicate that normal TDC values are affected differentially by BMI and age in a depth-dependent manner. Possible explanations are discussed.     

Woad extract containing cream improves significantly dry,irritated, and pruritic skin

Objective of this open, noninterventional, noncontrolled study was to investigate the tolerability and performance of a woad extract containing cream in subjects with dry, pruritic skin after twice daily application over 2 weeks. Assessments included sensorial characteristics, skin condition, pruritus (numeric rating scale [NRS], dynamic pruritus score [DPS]), skin dryness (itch‐controlled days [ItchCD], overall dry skin [ODS]), transepidermal water loss (TEWL), skin hydration and quality of life (5PLQ, DLQI). All sensorial characteristics were well perceived (>4), with tolerability (4.77 ± 0.47) and no negative skin feelings (4.73 ± 0.74) achieving the highest scores (0–5 scale). Dry skin and symptoms improved significantly (p < .001) for all variables: NRS (from 4.8 ± 1.74 to 1.83 ± 2.18), ItchCD (from 8.23 ± 4.40 to 4.81 ± 4.07), ODS (from 1.80 ± 0.85 to 0.65 ± 0.65), hydration (23.33 ± 1.33 to 40.70 ± 1.86), and quality of life (5PLQ: from 7.12 ± 4.25 to 4.24 ± 3.67; DLQI: from 5.29 ± 4.79 to 3.00 ± 3.98). The DPS revealed a moderate antipruritic effect. The TEWL decreased slightly (p = .511). No side effects were reported. The study suggests that, the cream is effective, and well tolerated in treating dry, irritated, and pruritic skin.     

内源性皮肤衰老研究新进展

皮肤衰老主要包括外源性和内源性衰老。外源性衰老主要为各种理化因素导致的皮肤老化。内源性衰老主要是随年龄增长导致的自然老化,其相关机制十分复杂,涉及基因、线粒体、端粒、激素水平等多种因素,但具体机制尚不明确。本文就近几年皮肤内源性衰老最新研究进展做一综述。     

Skin aging and dry skin

Skin aging appears to be the result of both scheduled and continuous "wear and tear" processes that damage cellular DNA and proteins. Two types of aging, chronological skin aging and photoaging, have distinct clinical and histological features. Chronological skin aging is a universal and inevitable process characterized primarily by physiologic alterations in skin function. In this case, keratinocytes are unable to properly terminally differentiate to form a functional stratum corneum, and the rate of formation of neutral lipids that contribute to the barrier function slows, causing dry, pale skin with fine wrinkles. In contrast, photoaging results from the UVR of sunlight and the damage thus becomes apparent in sun-exposed skin. Characteristics of this aging type are dry and sallow skin displaying fine wrinkles as well as deep furrows, resulting from the disorganization of epidermal and dermal components associated with elastosis and heliodermatitis. Understanding of the functions of the skin and the basic principles of moisturizer use and application is important for the prevention of skin aging. Successful treatment of dry skin with appropriate skin care products gives the impression of eternal youth.     

Effect of dermal thickness, tissue composition, and body site on skin biomechanical properties

BACKGROUND/PURPOSE: Quantitative measurement of skin biomechanical properties has been used effectively in the investigation of physiological changes in tissue structure and function and to determine treatment efficacy. As the methods are applied to new questions, tissue characteristics that may influence the resultant biomechanical properties are important considerations in the research design. For certain applications, variables such as dermal thickness and subdermal tissue composition, as well as age and/or solar exposure, may influence the skin biomechanics. METHODS: We determined the influence of dermal thickness, tissue composition, and age on the skin biomechanical properties at the shoulder, thigh, and calf among 30 healthy females. We compared two devices, the Biomechanical Tissue Characterization System and the Cutometer SEM 575 Skin Elasticity Meter , to determine the effect of tissue sampling size. Dermal thickness was measured with 20 MHz ultrasound (Dermascan C) and tissue composition was inferred from anthropomorphic data. RESULTS: Skin thickness was significantly correlated with stiffness, energy absorption, and U(r)/U(f) for the shoulder. Body mass index (BMI) was significantly correlated with stiffness (negative correlation), energy absorption (positive), and skin thickness (negative) for the shoulder. Significant differences across body sites were observed. The calf was significantly different from the thigh and shoulders for all parameters (P<0.05, one-way anova). The calf had significantly lower laxity, laxity%, elastic deformation, energy absorption, elasticity, elasticity %, U(r), U(f), and U(r)/U(f) and significantly higher stiffness compared with the thighs and shoulders. sites. The thigh and shoulder sites were significantly different for all parameters except U(r)/U(f), elasticity %, laxity%, and stiffness. The dominant and non-dominant sides were significantly different. The dominant side (right for 90% of the subjects) had increased stiffness and decreased energy absorption (tissue softness, compliance) compared with the left side. A significant (P< or =0.02) negative relationship with age was seen for all biomechanical measures except stiffness at the shoulder. For the thigh and calf sites, significant negative correlations with age were found for elasticity %, U(r), and U(r)/U(f). Age and skin thickness were not correlated in this population. Skin thickness and age influenced the energy absorption at the shoulder site. The biological elasticity at the calf site could be predicted by age and BMI. The biological activity at the thigh site could be predicted by skin thickness and BMI. CONCLUSIONS: Significant regional variations in biomechanical properties and dominant side effects were observed. The biomechanical properties were significantly influenced by age. Certain properties varied with dermal thickness and tissue composition. The parameters were well correlated between the two instruments. The Cutometer, with its smaller aperture, was found to be more sensitive to age relationships.