Biophysical Properties Of Skin Research Articles

Influence of Ethanol as a Preservative in Topical Formulation on the Dermal Penetration Efficacy of Active Compounds in Healthy and Barrier-Disrupted Skin

(1) Background: Ethanol is a multifunctional excipient often used as a preservative in topical formulations. Due to its known ability to impair skin barrier function, this study investigated the effect of ethanol (EtOH) as a preservative in creams on the dermal penetration of active compounds. (2) Methods: A hydrophilic and a lipophilic fluorescent dye were used as active ingredient surrogates that were incorporated into creams with and without ethanol. The dermal penetration efficacy was assessed by epifluorescence microscopy on an ex vivo porcine ear model with intact and irritated skin. (3) Results: Ethanol reduced the dermal penetration by about 40% for the hydrophilic and about 20% for the lipophilic surrogates on intact skin, but had minimal impact on irritated skin. The bio-physical skin properties were also altered by the addition of ethanol to the cream. On intact skin, it increased transepidermal water loss (TEWL) and decreased skin hydration, whereas on irritated skin, it decreased TEWL and increased skin hydration. The results indicate that skin impairment can be considered to have different stages, while in an early stage of skin impairment, the formation of a “Pudding skin” is proposed. A “Pudding skin” is the formation of a thin layer of dried skin on top of the skin that “seals” the lower parts of the skin and reduces dermal penetration and water loss from inside the skin and reduces the dermal penetration of chemical compounds from outside the skin. (4) Conclusions: Overall, the findings emphasize the need to carefully consider the use of ethanol in formulations, balancing its preservative benefits with its potential to impair the efficacy of active ingredients, particularly in varying skin conditions.

Preliminary safety and in vivo efficacy of Acmella oleracea extract‐loaded glycolipid emulsion serum—Effects on ocular irritation, dermal absorption, and facial skin biophysical and microrelief properties

AbstractObjectiveSubstantial efforts have been progressively devoted to developing innovative, safe, and effective topical anti‐aging products that not only improve the appearance of aged skin but also prioritize environmental sustainability and the responsible use of natural resources. Thus, the current study targeted to evaluate novel, natural emulsion/serum comprising new glycolipid emulsifier (lauryl glucoside/myristyl glucoside/polyglyceryl‐6 laurate) and Acmella oleracea plant extract as a model active.MethodsThe developed serum was assessed concerning its stability (freeze–thaw test, accelerated study), safety (in vitro screening of eye irritation potential, dermal absorption study) and efficacy (randomized, active/reference‐controlled, half‐face, in vivo study). Changes in skin biophysical properties, microrelief, roughness, texture, surface, and volume parameters were assessed in the periocular and perioral areas of human volunteers after 2 weeks of product application, utilizing several bioengineering and topography techniques.ResultsThe stability study demonstrated favourable stability profile of the developed serum, with practically unaffected stability‐indicating parameters (apparent viscosity, yield, flow point, storage and loss moduli, loss factor, pH, electrical conductivity) during freeze–thaw cycling and after 3 months of storage at 45°C. The hen's egg test on the chorioallantoic membrane of fertilized chicken eggs confirmed the absence of ocular irritation potential of investigated serum; no effects of haemorrhage, lysis or coagulation were occurred. Skin permeation study using diffusion cells revealed no permeation of spilanthol from the tested A. oleracea extract‐loaded serum through the pig ear skin into the receptor medium, thus suggesting no absorption into systemic circulation. In vivo efficacy study corroborated beneficial effects of evaluated serum on the condition/appearance of facial skin, at both periocular and perioral areas—significant (p < 0.05) increase in skin hydration (10%–40%) and smoothness (~15%); significant (p < 0.05) decrease in roughness (20%–30%), scaliness (~30%), and wrinkles (~15%)—implying more hydrated, smoother, visibly milder skin.ConclusionThe present findings confirmed the stability, preliminary safety (no ocular irritation, no dermal absorption, and good skin tolerability), and efficacy (improved skin hydration and microrelief) of the A. oleracea extract‐loaded, glycolipid‐based serum, supporting its potential as a safe and effective topical anti‐aging product.

IMPACT OF GENDER DIFFERENCES AND BODY MASS INDEX ON SKIN BIOPHYSICAL PARAMETERS OF CORONAVIRUS PATIENTS

Once the pandemic started, there were no clues regarding overall COVID-19 infections. There are no studies that demonstrate the effects of COVID-19 on skin surface pH, moisture, sebum, and temperature in terms of gender differences and body mass index (BMI) among infected people. The goal of this study was to investigate some of the skin biophysical scores of patients infected with COVID-19 and evaluate the impact of gender differences and the body mass index on them. Skin surface sebum, pH, temperature, and hydration (moisture), were measured in 30 COVID-19 patients using employing non-invasive portable devices. Insignificant effects of gender differences and BMI on skin biophysical properties were observed. In addition, females showed higher skin biophysical characteristics than males. Moreover, obese patients had higher skin biophysical parameter values than normal-weight patients. However, all the study results were statistically insignificant (p > 0.05). Further investigations are required to recognize other skin biophysical parameters such as transepidermal water loss and elasticity that may aid in the early identification of skin damage in COVID-19 patients.

Realistic Facial Age Transformation with 3D Uplifting

AbstractWhile current facial re‐ageing methods can produce realistic results, they purely focus on the 2D age transformation. In this work, we present an approach to transform the age of a person in both facial appearance and shape across different ages while preserving their identity. We employ an α‐(de)blending diffusion network with an age‐to‐α transformation to generate coarse structure changes, such as wrinkles. Additionally, we edit biophysical skin properties, including melanin and hemoglobin, to simulate skin color changes, producing realistic re‐ageing results from ages 10 to 80 years. We also propose a geometric neural network that alters the coarse scale facial geometry according to age, followed by a lightweight and efficient network that adds appropriate skin displacement on top of the coarse geometry. Both qualitative and quantitative comparisons show that our method outperforms current state‐of‐the‐art approaches.

Effects of spironolactone on skin biophysical properties in women with acne treated with oral spironolactone.

Spironolactone (SPL) is an effective treatment for women acne, but other effects on skin biophysical properties remain to be investigated. The aim of the current study was to explore the effects of oral SPL used to treat women acne on skin biophysical properties, including hydration, transepidermal water loss (TEWL), skin surface lipid (SSL) levels, mechanical properties, color, pH, and pore size. Twenty-five Thai women with acne treated with oral SPL were followed for 6 months. Skin hydration, TEWL, SSL levels, mechanical properties, color, pH, and pore size of the forehead, chest, and inner arm were evaluated at baseline and 2, 4, and 6 months after treatment with oral SPL. Facial and upper back pore size were also assessed. Clinical outcomes were changes in these skin biophysical properties at each visit compared with baseline. Skin hydration, TEWL, SSL levels, color, pH, and pore size remained stable throughout the study. Facial skin parameters at 6 months demonstrated the following changes: hydration levels, 7.60 (95% confidence interval [CI], -59.74 to 74.94); TEWL, -2.36 (95% CI, -5.77 to 1.06); L* value, 0.51 (95% CI, -0.70 to 1.72); individual typology angle, 1.65 (95% CI -2.27 to 5.57); pH, 0.01 (95% CI -0.43 to 0.46); pore size, -0.24 (95% CI, -1.21 to 0.73); and SSL levels, 7.60 (95% CI -59.74 to 74.94). Improvement of facial mechanical properties was observed. R0 (indicating skin tightness) and R1 (indicating elasticity) showed significant decreases (-0.076 [95% CI, -0.141 to -0.010] and -0.016 [95% CI, -0.033 to -0.001]). R3 and R4 (representing tiring effects) were also improved (-0.091 [95% CI, -0.158 to -0.025] and -0.022 [95% CI, -0.044 to -0.001]). Parameters in the truncal and inner arm areas remained stable, except for skin elasticity and tiring effects, which exhibited a similar trend of improvement as the facial area. The changes were notable as early as 4 months. Oral SPL used for acne did not impair the skin barrier. Moreover, the skin mechanical properties were improved at 4 to 6 months.

Біофізичні властивості шкіри щурів із метаболічним синдромом

It is known that metabolic syndrome (MS) prolongs the healing time of the wound surface of various genesis. We hypothesized that this may be related to changes in the biophysical properties of the skin. The aim of the work was to investigate the biophysical properties of skin (content of moisture, collagen, fused gelatin in the skin, and skin thermal fusion temperature) in rats with MS. Materials and methods. Research was conducted on 40 white non-linear rats (20 – males, 20 – females). After birth, males and females were divided into 2 groups. The first group served as a control for the second groups, in which MS was simulated by administering monosodium glutamate at a dose of 4.0 mg/kg on the 2nd, 4th, 6th, 8th, and 10th postnatal days. At the age of 4 months, the animals were decapitated under ether anesthesia. Biochemical studies were conducted to confirm the development of MS. The percentage of moisture, collagen content, destructive changes in collagen fibers and resistance of skin collagen to thermal factors were determined in native skin. The results. 4-month-old rats injected with monosodium glutamate in the early neonatal period developed MS as evidenced by abdominal obesity, insulin resistance, and dyslipidemia. In comparison with animals of the control group, in the skin of male and female rats with MS, the moisture content decreased, and the collagen content did not change. At the same time, the percentage of melted gelatin doubled, which indicates the depth of destructive changes in collagen fibers. Thermal welding of skin samples of male and female rats with signs of MS occurred at rather low temperatures compared to rats of the control group. Conclusion. Changes in the biophysical properties of the skin, which are registered in rats with MS, may be the reason for the later closure of the wound surface.

The Assessment of the Long-Term Impact of Radiotherapy on Biophysical Skin Properties in Patients after Head and Neck Cancer.

Background and Objectives: Chronic radiotherapy-induced skin injury (cRISI) is an irreversible and progressive condition that can significantly impact a patient's quality of life. Despite the limited literature available on the assessment of the epidermal barrier in cRISI, there is a consensus that appropriate skincare, including the use of emollients, is the primary therapeutic approach for this group of patients. The aim of this study was to evaluate the biophysical properties of the skin during the late period (at least 90 days) following radiation therapy (RT) for head and neck cancer. Materials and Methods: This was a single-center prospective non-randomized study. It involved the analysis of 16 adult patients with head and neck cancer who underwent RT at the Greater Poland Cancer Center, along with 15 healthy volunteers. The study and control groups were matched for gender and age (p = 0.51). Clinical assessment, based on the LENT-SOMA scale, was conducted for all patients. Evaluation of the skin's biophysical properties included: an analysis of transepidermal water loss (TEWL), stratum corneum hydration (SCH), and skin visualization using high-frequency ultrasonography (HF-USG). Results: A significantly higher TEWL was observed in the irradiated area compared to the control area in the study group (p = 0.004). However, there was no statistically significant difference in SCH (p = 0.073). Additionally, no significant difference was observed in the values of TEWL and SCH in the irradiated area between the group of patients with and without clinically obvious RISI (p = 0.192 and p = 0.415, respectively). The skin thickness of the irradiated area, assessed by HF-USG, did not differ significantly from the skin thickness of the control area (p = 0.638). Furthermore, no difference in skin thickness was observed in patients with clinical features of cRISI in the irradiated and control areas (p = 0.345). The mean time after RT was 6.1 years. Conclusions: This study marks the first demonstration of epidermal barrier damage in patients in the long term following RT for head and neck cancer. The impairment of the epidermal barrier was observed independently of evident cRISI features. This observation underscores the necessity to recommend appropriate skin care, including the use of emollients, for all patients following RT. We also suggest that HF-USG examination is generally inconclusive in determining the degree of skin damage in the late period after RT.

Objective Non-Invasive Bio-Parametric Evaluation of Regenerated Skin: A Comparison of Two Acellular Dermal Substitutes.

Several dermal substitutes are available on the market, but there is no precise indication that helps surgeons choose the proper one. Few studies have tried to compare different xenogeneic bioengineered products, but no objective bio-parametric comparison has been made yet. Fifteen patients who underwent skin reconstruction with Integra® or Pelnac® were retrospectively evaluated. After at least 12 months of follow-up, an objective and quantitative assessment of several skin biophysical properties, such as color, texture, elasticity, hydration, glossiness and trans-epidermal water loss, were measured with non-invasive skin measurement devices. The grafted skin showed a reduction of the superficial hydration level and a tendency to lower values of trans-epidermal water loss with both dermal substitutes. Melanic and hemoglobin pigmentation were higher in comparison to the donor site in both groups, while a melanic pigmentation increase versus the surrounding skin was seen just with Integra®. Finally, the skin was found to be more elastic when reconstructed with Integra®. The skin barrier appeared to be intact in both groups. Hence, these substitutes are valuable means of skin regeneration. Integra® seems to be more advantageous for reconstructing areas that need more skin flexibility.

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.

Adhesives for medical application - Peel strength testing and evaluation of biophysical skin response

BackgroundMedical adhesives are commonly used for securing wound dressings and medical devices used for diagnostic or therapeutic purposes. Mechanical irritation of skin due to adhesive stripping and repeated application can lead to discomfort and device removal. This study aims to examine the peel strength and skin response to different medical adhesives in a cohort of healthy volunteers. MethodTwelve healthy participants were recruited for peel strength testing of three candidate adhesive tapes, and evaluation of the skin response after adhesive removal. A modified ASTM D903 peel strength testing was performed at 180° peeling angle and a rate of 300 mm/min on the forehead, upper back and forearm skin. A longitudinal study was conducted on the forearm and back, with the adhesive samples left in-situ for up to 60 h for analysis of repeat application. The effects of two skin preparation approaches (water and alcohol cleaning) prior to adhesive application were also assessed. Skin biophysical properties were assessed at baseline and at various timepoints following adhesive removal using transepidermal water loss (TEWL), erythema and hydration. ResultsPeel strength reduced uniformly with repeat application over prolonged periods for all the adhesive samples tested. Skin preparation with water and alcohol cleansing prior to adhesive application increased peel strength at both the back (1.1% and 2.9%), and forearm (21.3% and 20%) sites. There was statistically significant increase from baseline to post-tape application for TEWL, skin redness and hydration (p < 0.001). However, there were no statistically significant differences between adhesive types (TEWL: p = 0.38, SR: p = 0.53, HY: p = 0.46). TEWL increased the most post-adhesion across all test sites and adhesive samples with repeat application (p < 0.05). Two-way ANOVA tests revealed no statistically significant interactions between the effects of application duration and adhesive on skin redness or TEWL for both the back and forearm sites (p > 0.05), though a significant interaction was indicted for hydration at the back site (p = 0.01). ConclusionThis study revealed that site and duration of adhesive application effected peel strength. The corresponding changes in skin properties identified that skin barrier function was disrupted with long-term application of adhesives. The back site was identified to be most reliable for adhesion testing and skin response assessment for future work.

Skin manifestations and biophysical changes following weight reduction induced by bariatric surgery: A 2-year prospective study.

Skin manifestations and biophysical changes are observed in patients with morbid obesity. However, reports of changes after significant weight loss, particularly through post-bariatric surgery (BaS), are limited. The aim of this 2-year prospective study was to evaluate the prevalence of skin signs and their changes in patients with morbid obesity who underwent BaS. Thirty-one patients were recruited for the study, with a mean age of 38.35 (SD 10.61) years and a male preponderance (male = 19 [61.29%], female = 12 [38.71%]). Patients were scheduled for multiple visits at months 0, 3, 6, 12, 18, and 24 post-BaS. Each subject had a thorough skin examination, biophysical measurements, and laboratory tests at each visit. Striae, acanthosis nigricans (AN), and plantar hyperkeratosis were the most common skin findings (n = 30 [96.77%], 29 [93.55%], 29 [93.55%], respectively). BaS provided improvements in many skin manifestations, namely striae, AN, acrochordons, plantar hyperkeratosis, hirsutism, lymphedema, pruritus, acne, finger pebbles, and chronic venous insufficiency with varied cumulative rates of improvements. However, acute telogen effluvium was observed in 17 (54.84%) patients. Regarding skin biophysical properties, transepidermal water loss, skin hydration, and pH did not change, while sebum production on the face significantly decreased at months 3 and 6, and elasticity decreased at months 6 and 24. In conclusion, weight reduction by BaS provided improvements in various skin signs, although telogen effluvium was a common sequelae.

Correlating the Gut Microbiota and Circulating Hormones with Acne Lesion Counts and Skin Biophysical Features.

Acne vulgaris is a common inflammatory condition that is multi-factorial and impacted by both intrinsic and extrinsic features. Several previous studies have assessed for correlations between factors such as circulating hormones, stress, or the microbiome. However, there have not been any correlations specifically against lesion counts or differentiating correlations between inflammatory and non-inflammatory lesion counts. Here, we correlate several factors against acne lesions. Twenty men and women with mild to moderate acne were recruited, and their hormonal levels and their gut microbiome were collected and correlated against their inflammatory and non-inflammatory lesions of acne. Facial non-inflammatory lesions were weakly correlated to sebum excretion rate and weakly inversely correlated to forehead and cheek hydration. We examined stress through the use of a normalized peak-to-trough ratio (higher numbers indicated less stress), which correlated with skin hydration and inversely correlated with sebum excretion rate. Sebum excretion rate was weakly correlated to testosterone levels, and facial hydration correlated with estradiol levels. Correlations with the gut microbiome showed differential correlations with inflammatory and non-inflammatory lesions, with Clostridium sp AF 23-8 correlating to inflammatory lesion counts, while Actinomyces naeslundii str Howell 279 correlated to non-inflammatory lesions. Overall, measures of stress and circulating hormones correlate to skin biophysical properties and acne lesion counts. Also, different gut bacteria correlate with either inflammatory or non-inflammatory lesion counts. We hope that our findings stimulate further work on the gut-mind-stress-skin axis within acne.

Poroelastic behavior and water permeability of human skin at the nanoscale.

Topical skin care products and hydrating compositions (moisturizers or injectable fillers) have been used for years to improve the appearance of, for example facial wrinkles, or to increase "plumpness". Most of the studies have addressed these changes based on the overall mechanical changes associated with an increase in hydration state. However, little is known about the water mobility contribution to these changes as well as the consequences to the specific skin layers. This is important as the biophysical properties and the biochemical composition of normal stratum corneum, epithelium, and dermis vary tremendously from one another. Our current studies and results reported here have focused on a novel approach (dynamic atomic force microscopy-based nanoindentation) to quantify biophysical characteristics of individual layers of ex vivo human skin. We have discovered that our new methods are highly sensitive to the mechanical properties of individual skin layers, as well as their hydration properties. Furthermore, our methods can assess the ability of these individual layers to respond to both compressive and shear deformations. In addition, since human skin is mechanically loaded over a wide range of deformation rates (frequencies), we studied the biophysical properties of skin over a wide frequency range. The poroelasticity model used helps to quantify the hydraulic permeability of the skin layers, providing an innovative method to evaluate and interpret the impact of hydrating compositions on water mobility of these different skin layers.

Semi-Solid Dosage Forms Containing Pranoprofen-Loaded NLC as Topical Therapy for Local Inflammation: In Vitro, Ex Vivo and In Vivo Evaluation.

Pranoprofen (PRA)-loaded nanostructured lipid carriers (NLC) have been dispersed into blank gels composed of 1% of Carbomer 940 (PRA-NLC-Car) and 3% of Sepigel® 305 (PRA-NLC-Sep) as a novel strategy to refine the biopharmaceutical profile of PRA, for dermal administration in the treatment of skin inflammation that may be caused by possible skin abrasion. This stratagem intends to improve the joining of PRA with the skin, improving its retention and anti-inflammatory effect. Gels were evaluated for various parameters such as pH, morphology, rheology, and swelling. In vitro drug release research and ex vivo permeation through the skin were carried out on Franz diffusion cells. Additionally, in vivo assays were carried out to evaluate the anti-inflammatory effect, and tolerance studies were performed in humans by evaluating the biomechanical properties. Results showed a rheological profile common of semi-solid pharmaceutical forms for dermal application, with sustained release up to 24 h. In vivo studies using PRA-NLC-Car and PRA-NLC-Sep in Mus musculus mice and hairless rats histologically demonstrated their efficacy in an inflammatory animal model study. No signs of skin irritation or modifications of the skin's biophysical properties were identified and the gels were well tolerated. The results obtained from this investigation concluded that the developed semi-solid formulations represent a fitting drug delivery carrier for PRA's transdermal delivery, enhancing its dermal retention and suggesting that they can be utilized as an interesting and effective topical treatment for local skin inflammation caused by a possible abrasion.

O/W/O multiple emulsions containing soluble collagen: in vitro and in vivo skin biophysical properties evaluation

The integrity of the stratum corneum is essential for skin hydration. In order to fulfill all of its functions, a balance of the water content in the stratum corneum is necessary, as well as maintaining the epidermis, an essential objective of cosmetic formulations. Cosmetic skin hydration can be achieved through the frequent application of cosmetic products that can act through basic mechanisms: occlusion, moisturization, and hydration or active moisturization. Therefore, when developing new cosmetic products, it is important to consider their positive effect on skin hydration and viscoelasticity, considering that the objective of a cosmetic product is to protect the skin and delay skin aging. Subsequently, multiple O/W/O emulsions were developed and skin hydration was evaluated in vitro and in vivo. The in vitro method for skin hydration employs gelatin whose composition mimics collagen and NMF of the skin, forming a surface (1 cm thick) through which internal water vapor can be released. The occlusion provided to this gelatin surface is evaluated, and the hydrating power of the applied products is determined. Due to the composition of the gelatin support cell and the evaporation of water inside it, it can simulate TEWL of the skin. The in vivo evaluation of hydration, pH, and sebum of the aqueous solution of proteins, simple O/W, and multiple O/W/O with collagen showed that O/W/O emulsions provided greater occlusive and oily content, maintaining the pH levels of the skin. Therefore, these O/W/O systems improve conditions for dry skin.

The effect of adjuvant radiotherapy on skin biophysical properties in patients with breast cancer at risk for breast lymphedema: A prospective study.

Breast cancer (BC) is the most common type of cancer among women. Radiotherapy (RT) is one of the main and primary treatment options for BC, especially in breast-conserving surgery (BCS). BC patients who underwent RT experience a wide range of symptoms, in which breast oedema and irritation of the skin take the lion's share. Breast oedema/lymphedema, which is also a prominent side effect after RT should be well determined in earlier settings due to the chronicity of lymphedema. Therefore, this study aimed to analyze the biophysical parameters of skin on the ipsilateral (IL) and contralateral (CL) sites via Tissue dielectric constant (TDC) and Transepidermal water loss (TEWL) methods in terms of oedema and skin barrier function (SBF). The following reference points before and after the RT were measured: (R1: Pectoralis muscle, R2: Upper breast, R3: Lower breast, R4: Lateral site of the thorax). A total of 24 BC patients (mean age and BMI: 52.78 ± 9.85 years and 28.42 ± 5.64 kg/m2 ) were evaluated. In the IL site, the SBF was not found significant in R1-R3, whereas significantly lower SBF was observed in R4 after RT (t = -3.361, p = 0.003). A significant increase in TDC was observed in R2 at the 5.0 mm depth (t = -2.500, p = 0.02). We suggest that a longer period of follow-up should be carefully carried out to track changes in terms of SBF and oedema in the irradiated breast. The increased need for early detection of changes associated with breast lymphedema can be achievable via noninvasive, safe, cheap, and easily repeatable devices.

The Effects of a Fasting Mimicking Diet on Skin Hydration, Skin Texture, and Skin Assessment: A Randomized Controlled Trial.

Diet and nutrition have been shown to impact dermatological conditions. This has increased attention toward integrative and lifestyle medicine in the management of skin health. Emerging research around fasting diets, specifically the fasting-mimicking diet (FMD), has provided clinical evidence for chronic inflammatory, cardiometabolic, and autoimmune diseases. In this randomized controlled trial, we evaluated the effects of a five-day FMD protocol, administrated once a month for three months, on facial skin parameters, including skin hydration and skin roughness, in a group of 45 healthy women between the ages of 35 to 60 years old over the course of 71 days. The results of the study revealed that the three consecutive monthly cycles of FMD resulted in a significant percentage increase in skin hydration at day 11 (p = 0.00013) and at day 71 (p = 0.02) relative to baseline. The results also demonstrated maintenance of skin texture in the FMD group compared to an increase in skin roughness in the control group (p = 0.032). In addition to skin biophysical properties, self-reported data also demonstrated significant improvement in components of mental states such as happiness (p = 0.003) and confidence (0.039). Overall, these findings provide evidence for the potential use of FMD in improving skin health and related components of psychological well-being.

An evaluation of mechanical and biophysical skin parameters at different body locations.

Skin is the largest organ in the body, representing an important interface to monitor health and disease. However, there is significant variation in skin properties for different ages, genders and body regions due to the differences in the structure and morphology of the skin tissues. This study aimed to evaluate the use of non-invasive tools to discriminate a range of mechanical and functional skin parameters from different skin sites. A cohort of 15 healthy volunteers was recruited following appropriate informed consent. Four well-established CE-marked non-invasive techniques were used to measure four anatomical regions: palm, forearm, sole and lower lumbar L3, using a repeated measures design. Skin parameters included trans-epidermal water loss (TEWL), pH (acidity), erythema, stratum corneum hydration and stiffness and elasticity using Myoton Pro (skin and muscle probe). Differences between body locations for each parameter and the intra-rater reliability between days were evaluated by the same operator. The results indicate that parameters differed significantly between skin sites. For the Myoton skin probe, the sole recorded the highest stiffness value of 1006 N/m (SD±179), while the lower lumbar recorded the least value of 484 N/m (SD±160). The muscle indenter Myoton probe revealed the palm's highest value of 754 N/m (±108), and the lower lumbar recorded the least value of 208 N/m (SD±44). TEWL values were lowest on the forearm, averaging 11g/m2/h, and highest on the palm, averaging 41g/m2/h. Similar skin hydration levels were recorded in three of the four sites, with the main difference being observed in the sole averaging 13 arbitrary units. Erythema values were characterised by a high degree of inter-subject variation, and no significant differences between sites or sides were observed. The Myoton Pro Skin showed excellent reliability (intra-class correlation coefficients>0.70) for all sites with exception of one site right lower back; the Myoton pro muscle probes showed good to poor reliability (0.90-017), the corneometer showed excellent reliability (>0.75) among all the sites tested, and the TEWL showed Good to poor reliability (0.74-0.4) among sites. The study revealed that using non-invasive methods, the biophysical properties of skin can be mapped, and significant differences in the mechanical and functional properties of skin were observed. These parameters were reliably recorded between days, providing a basis for their use in assessing and monitoring changes in the skin during health and disease.

Prospective Placebo-Controlled Assessment of Spore-Based Probiotic Supplementation on Sebum Production, Skin Barrier Function, and Acne.

Probiotic supplementation has been shown to modulate the gut-skin axis. The goal of this study was to investigate whether oral spore-based probiotic ingestion modulates the gut microbiome, plasma short-chain fatty acids (SCFAs), and skin biophysical properties. This was a single-blinded, 8-week study (NCT03605108) in which 25 participants, 7 with noncystic acne, were assigned to take placebo capsules for the first 4 weeks, followed by 4 weeks of probiotic supplementation. Blood and stool collection, facial photography, sebum production, transepidermal water loss (TEWL), skin hydration measurements, and acne assessments were performed at baseline, 4, and 8 weeks. Probiotic supplementation resulted in a decreasing trend for the facial sebum excretion rate and increased TEWL overall. Subanalysis of the participants with acne showed improvement in total, noninflammatory, and inflammatory lesion counts, along with improvements in markers of gut permeability. The gut microbiome of the nonacne population had an increase in the relative abundance of Akkermansia, while the subpopulation of those with acne had an increase in the relative abundance of Lachnospiraceae and Ruminococcus gnavus. Probiotic supplementation augmented the circulating acetate/propionate ratio. There is preliminary evidence for the use of spore-based probiotic supplementation to shift the gut microbiome and augment short-chain fatty acids in those with and without acne. Further spore-based supplementation studies in those with noncystic acne are warranted.

Oral Supplementation of Low-Molecular-Weight Collagen Peptides Reduces Skin Wrinkles and Improves Biophysical Properties of Skin: A Randomized, Double-Blinded, Placebo-Controlled Study.

Orally administered collagen peptides could contribute to antiaging by replacing the degraded extracellular matrix proteins caused by photoaging. This study aimed to evaluate the efficacy and safety of low-molecular-weight collagen peptides for treating photoaged and dry skin. In this randomized, placebo-controlled, parallel-group, double-blinded trial, we randomly assigned study participants (n = 100) to either the test product group or placebo group at a 1:1 ratio for 12 weeks. The wrinkle scale score, eye wrinkle volume, roughness parameters, such as the average maximum height of the wrinkle (Rz), arithmetic average within the total measuring length of the wrinkle (Ra), maximum profile valley depth of the wrinkle (Rv), and skin hydration, transepidermal water loss (TEWL), overall elasticity (R2), and ratio of elastic recovery to total deformation (R7) were evaluated at baseline, 6 weeks, and 12 weeks. Safety assessments with serial blood tests were also conducted. Efficacy assessments of data from 84 participants were conducted as the per-protocol analysis. After 12 weeks, the 10-grade crow's feet photo scale score, eye wrinkle volume, skin roughness parameters (Rz, Ra, and Rv), skin elasticity (R2 and R7), skin hydration, and TEWL were significantly improved in the test product group compared to the placebo group. There were no adverse events or abnormalities according to laboratory analysis associated with using the test material during the study period. This study showed that the oral supplementation of low-molecular-weight collagen peptides could improve the wrinkles, elasticity, hydration, and barrier integrity of photoaged facial skin. This clinical study was registered with the Korean Clinical Research Information Service and International Clinical Trials Registry Platform (No: KCT0006500).