Correlation study between image features and mechanical properties of Han Chinese facial skin

Skin inflammatory signatures, as measured by disordered spatial redness patterns, predict current and future skin ageing attributes

Facial skin redness can be an indicator of skin inflammation, however the physiological connection between facial redness and inflammatory status, as well as its role in age-related skin changes, remains poorly understood. This study aims to investigate the association between the pattern of facial skin redness and biological inflammatory status, as well as age-related changes occurring in the skin. Four studies were conducted recruiting healthy Northern Asian females. Disordered spatial patterns of facial skin redness signals were assessed using image analysis, i.e., the a* gradient algorithm, which quantifies the disordered shape and pattern of localized redness signals on facial skin. This redness pattern was compared with (1) inflammatory protein markers (IL-1Ra/ IL-1α and IL-8) measured from stripped corneocyte samples, (2) gene expression profiles obtained through transcriptome analysis using skin biopsy samples, and (3) the distribution pattern of blood vessel measured using a photoacoustic microscope. The association between the skin redness pattern and current and future ageing-related skin changes was examined through a longitudinal study tracking the same subjects for 10 years. A significant correlation was observed between the a* gradient and the levels of inflammatory cytokines (IL-1Ra/IL-1α and IL-8). Transcriptome analysis revealed upregulation of genes related to acute inflammation, chronic inflammation, cellular senescence, and angiogenesis in subjects with higher a* gradients. The high a* gradient group exhibited an extension of blood vessel diameter and increased blood vessel density, while the medium a* gradient group only exhibited blood vessel extension. Lastly, the 10-year longitudinal study demonstrated that the a* gradient was associated with current and future skin ageing-related attributes, such as increased skin texture and wrinkle formation. The spatial pattern of localized redness on the skin reflects the biological inflammatory status, and this inflammatory condition helps predict current and future age-related skin changes.

Disordered spatial pattern of redness signal on facial skin and visual perception of health, stress, and hidden aging

BACKGROUND

Well-being is commonly communicated across industries; however, experimental understanding how human perceive skin health and skin stresses are not sufficient.

MATERIALS AND METHODS

Image analysis algorithm, a* gradient, was developed to evaluate spatial pattern and shape of red signal on skin. Human perception for skin health and stresses were compared with technical measurements in two visual perception studies.

RESULTS

a* gradient correlated with perceived Inflamed Skin (R = 0.73, p < 0.01), Stressed Skin (R = 0.79, p < 0.01), Sensitive Skin (R = 0.75, p < 0.01), Healthy Skin (R = -0.83, p < 0.01), and Start Aging (R = 0.75, p < 0.01).

CONCLUSIONS

Disordered spatial pattern of redness signal drives human perception of skin health, stress, and aging. This new skin index of redness signal shows higher correlation with those human perception than basal a* mean, unevenness of a*, and other conventional skin color attributes.

Biophysical effects of a natural peloid on normal skin

A protocol study was designed to examine cutaneous behavior after continuous application of a peloid in the dry mineral residue of Lanjarón-Capuchina natural mineral water. This study aims to analyze the biomechanical behavior of normal skin using various non-invasive bioengineering techniques after the application of this peloid. We determine the effects of its application for 3 months on 38 healthy volunteers (41.4 ± 5.9 years, range 32-58) without a previous history of skin diseases by courtmetry, sebumetry, pH-metry, reviscometry, and tewametry. It was shown that the production of cutaneous sebum is significantly reduced by 6%, trans epidermal skin loss (TEWL) by 21%, skin fatigue by 30%, elasticity increased by 19%, firmness by 5%, and a skin redensification by 6% was obtained under these experimental conditions. Disparate and non-significant results were obtained concerning pH and viscoelasticity. Continuous skin care with the Lanjarón-Capuchina natural peloid modifies skin behavior, normalizing sebaceous secretion, favoring the biomechanical properties of the skin and the skin barrier function without modifying skin homeostasis.

Diversity of Asian skin: A review on skin biophysical properties

Asian is home to dozens of different ethnic groups that are characterised by fascinating social and cultural variations. Unfortunately, existing literature on the skin properties of Asians tends to group this diverse population solely based on skin colour, perpetuating the misconception and stereotype that all Asian skin is the same. While Asia is one of the largest continents in the world, the difference in the geographical location and climate have long shaped the population into various ethnic groups with significant differences in the collective and diverse customs, traditions, cultures and living habits. The diverse ethnic groups in this region hint us that their skin biophysical characteristics can be very different from each other. This review features the profiling of the distinctive skin biophysical properties of Asians. We learn more about the different ethnic groups in Asia and acknowledge the unique skin biophysical properties even from the same country.

Evaluation of facial skin age based on biophysical properties in vivo

OBJECTIVE

The evaluation of skin age, reflecting overall facial characteristics, has not been established. Previous studies focused on visual assessment or individual-specific feature such as wrinkles or skin color. We studied the evaluation model of skin age index (SAI) including the overall aging features including wrinkles, skin color, pigmentation, elasticity, and hydration.

METHODS

Total 300 healthy women aged between 20 and 69 years included in this study. Pearson correlation analysis performed to identify the key factors among the biophysical properties with aging and developed the prediction model of SAI. Statistical regression analysis and machine learning technique applied to build the prediction model using the coefficient of determination (R² ) and root mean square error (RMSE). Validation study of the SAI model performed on 24 women for 6 weeks application with anti-aging product.

RESULTS

Prediction model of SAI consisted of skin elasticity, wrinkles, skin color (brightness, Pigmented spot, and Uv spot), and hydration, which are major features for aging. The cforest model to assess a SAI using machine learning identified the highest R² and lowest RMSE compared to other models, such as svmRadial, gaussprRadial, blackboost, rpart, and statistical regression formula. The cforest prediction model confirmed a significant decrease of predicted SAI after 6 weeks of application of anti-aging product.

CONCLUSION

We developed a prediction model to evaluate a SAI using machine learning, and led to accurate predicted age for overall clinical aging. This model can a good standard index for evaluating facial skin aging and anti-aging products.

Quantitative assessment and influence factors of facial wrinkle situation in male construction workers in Beijing

OBJECTIVE

To investigate current situation of facial wrinkles of male construction workers in Beijing area and to discuss the correlative factors.

MATERIALS AND METHODS

A total of 149 male construction works and 63 male non-construction workers in Beijing were required to complete a questionnaire on their exposure to sunlight, dust, noise, and heat in their workplace environment. Their facial wrinkle scores were measured by VISIA Complexion Analysis System. The two-sample t test, chi-square test, and multiple linear regression were used for statistical analysis RESULTS: The exposure to sunlight, dust, noise, and heat of construction workers was significantly higher than that of non-construction workers (P < .01). The wrinkle score of construction workers between 20 and 29 years old was significantly higher than that of non-construction workers (t = 4.077, P < .01). The facial wrinkle score of construction workers(r = 0.657, P < .01) and non-construction workers (r = 0.681, P < .01) was both positively correlated with age. The wrinkle score of construction workers was related to age, sunlight, and noise(P < .01).

CONCLUSION

The wrinkle score of male construction workers between 20 and 29 years old is significantly higher than that of non-construction workers in Beijing. Age, sunlight, and noise were the main influencing factors of wrinkle.

A blackberry-dill extract combination synergistically increases skin elasticity

BACKGROUND

The loss of structural elastin due to intrinsic and extrinsic ageing results in the skin's inability to stretch and recoil (decrease in elasticity) and manifests as loss of skin firmness and sagging. While other extracellular matrix (ECM) components such as collagen and hyaluronic acid are continually synthesized and assembled through life, elastic fibres are not. Elastic fibre assembly and functionality require fibre cross-linking, induced by the lysyl oxidase-like (LOXL) enzymes, which sharply decrease during ageing.

OBJECTIVE

To evaluate the enhanced elastogenic effect of a blackberry-dill extract combination, which was hypothesized to induce elastin fibre component synthesis, fibre cross-linking and reduce elastin fibre degradation.

METHODS

The blackberry and the dill extracts were tested separately and in combination to confirm single ingredient bioactivity and synergistic benefits. Human skin explants, dermal fibroblasts, elastase assays, ELISAs, quantitative real-time PCRs and spectrofluorometer measurements were used. Moreover, a double-blinded, placebo-controlled clinical study was carried out to assess skin elasticity using Cutometer and histologically from biopsies.

RESULTS

The blackberry extract induced elastin gene expression, elastin promoter activity and inhibited elastic fibre degradation by matrix metalloproteinases (MMPs) 9 and 12. The dill extract induced elastin, collagen and LOXL1 gene expression, resulting in enhanced fibre cross-linking in human skin explants. Clinically, the blackberry and dill combination treatment displayed synergistic pro-elasticity activity as compared to each ingredient alone and placebo.

CONCLUSION

Taken together, these results demonstrated the two multimodal plant-based extracts complemented each other in terms of bioactivity and resulted in a synergistic elastogenesis induction.