Topically applied vitamin C increases the density of dermal papillae in aged human skin

Topical retinoids: Novel derivatives, nano lipid-based carriers, and combinations to improve chemical instability and skin irritation

BACKGROUND

Retinoids, defined as synthetic or natural derivatives of vitamin A, have been extensively studied as anti-aging molecules that are widely applied in cosmetics. However, due to their physicochemical property, retinoids are highly unstable and extremely sensitive to light, oxygen, and temperature. Moreover, topical application of retinoids often leads to cutaneous irritation. These instabilities and irritant properties of retinoids limit their application in cosmetic and pharmaceutical products.

AIM

Our study aimed to provide a systematic review to summarize the mechanisms underlying the instability and irritant properties of retinoids, as well as recent developments in addressing these challenges.

METHODS

A comprehensive PubMed search was conducted using the following keywords: retinoids, chemical instability, skin irritation, retinoid derivatives, nano lipid-based carriers, liposomes, penetration-enhancer vesicles, ethosomes, niosomes, nanoemulsions, solid lipid nanoparticles, vitamins, soothing and hydrating agents, antioxidants and metal chelator and retinol combinations. Relevant researches published between 1968 and 2023 and studies related to these reports were reviewed.

RESULTS

The development of new retinoid derivatives, the utilization of new delivery systems like nano lipid-based carriers and the combination with other compounds like vitamins, soothing agents, antioxidants and metal chelator have been explored to improve the stability, bioavailability, and toxicity of the retinoid family.

CONCLUSIONS

Through advancements in formulation techniques, structure modification of retinoid derivatives and development of novel nano lipid-based carriers, the chemical instability and skin irritation of retinoids has been mitigated, ensuring their efficacy and potency over extended periods.

Ascorbic Acid Treatments as Effective and Safe Anti-Aging Therapies for Sensitive Skin

The most common signs of aging skin include a decrease in firmness and density, uneven skin tone, and a tendency to erythema. There is an ever-increasing interest in aesthetic treatments that maintain the skin's favorable appearance. However, such therapies are difficult in the case of sensitive skin, defined as a set of stimuli-triggered symptoms (stinging, erythema, burning, and itching) that would not appear in healthy skin. Sensitive skin is common and affects, to varying degrees, about half of the European population. This study was aimed at evaluating the effects of ascorbic acid-a known antioxidant-applied with sonophoresis and microneedling on the signs of photoaging in reactive and erythematous skin. A significant improvement in skin elasticity was observed after a series of tests. A significant reduction in erythema was observed after both therapies. The greatest reduction was observed on the cheeks after applying vitamin C combined with microneedling. At the same time, the results showed an excellent tolerance of both treatments, which proved them to be safe and effective.

Quantitative morphometric analysis of intrinsic and extrinsic skin ageing in individuals with Fitzpatrick skin types II-III

Skin ageing is an intricate physiological process affected by intrinsic and extrinsic factors. There is a demand to understand how the skin changes with age and photoexposure in individuals with Fitzpatrick skin types I-III due to accelerated photoageing and the risk of cutaneous malignancies. To assess the structural impact of intrinsic and extrinsic ageing, we analysed 14 skin parameters from the photoprotected buttock and photoexposed dorsal forearm of young and ageing females with Fitzpatrick skin types II-III (n = 20) using histomorphic techniques. Whilst the minimum viable epidermis (Emin ) remained constant (Q > 0.05), the maximum viable epidermis (Emax ) was decreased by both age and photoexposure (Q ≤ 0.05), which suggests that differences in epidermal thickness are attributed to changes in the dermal-epidermal junction (DEJ). Changes in Emax were not affected by epidermal cell proliferation. For the first time, we investigated the basal keratinocyte morphology with age and photoexposure. Basal keratinocytes had an increased cell size, cellular height and a more columnar phenotype in photoexposed sites of young and ageing individuals (Q ≤ 0.05), however no significant differences were observed with age. Some of the most striking changes were observed in the DEJ, and a decrease in the interdigitation index was observed with both age and photoexposure (Q ≤ 0.001), accompanied by a decreased height of rête ridges and dermal papilla. Interestingly, young photoexposed skin was comparable to ageing skin across many parameters, and we hypothesise that this is due to accelerated photoageing. This study highlights the importance of skin care education and photoprotection from an early age.

A Subjective and Objective Assessment of Combined Methods of Applying Chemical Peels and Microneedling in Antiaging Treatments

Combined methods of applying chemical peels and antioxidants could be an option for skin rejuvenation with no down-time. The penetration of active substances can be enhanced by microneedle mesotherapy. The study was conducted on a group of 20 female volunteers, aged 40-65 years. All volunteers received a series of eight treatments performed every seven days. The whole face was first treated with azelaic acid; following this, the right side received a 40% solution of vitamin C and the left side 10% vitamin C with microneedling. Hydration and skin elasticity were markedly improved, with better results observed on the microneedling side. Melanin and erythema index decreased. No significant side effects were seen. The combination of active ingredients and delivery techniques have great potential to enhance the effectiveness of cosmetic preparations, probably by multidirectional ways of action. In our study, we demonstrated that both 20% azelaic acid + 40% vitamin C treatment and 20% azelaic acid + 10% vitamin C + microneedle mesotherapy efficiently improved the assessed parameters of aging skin. However, the use of microneedling mesotherapy as a means of direct delivery of active compound to the dermis enhanced the effectiveness of the studied preparation.

Clinical evaluation of anti-aging effects of combined therapy-Azelaic acid, phytic acid, and vitamin C applied layer by layer in females with Fitzpatrick skin types II and III

INTRODUCTION

Vitamins C, E, and A and substances of plant origin, including azelaic acid and phytic acid are frequently used in cosmetic preparations to counteract oxidative stress and negative effects of free radicals. The aim of the study was to evaluate a novel combined therapy consisting of azelaic acid, ascorbic acid, and phytic acid applied layer on layer.

METHODS

Twenty study participants received a series of eight treatments performed every 7 days. Twenty percent azelaic acid and then 30% phytic acid were applied to the entire face, while 40% l-ascorbic acid only on the left side. The preparations were applied layer by layer. Skin parameters were measured before the series of treatments (T0), after the series of eight treatments (T1-8 weeks), and 1 month after the end of the treatment (T2-12 weeks).

RESULTS

The application of two and three active compounds resulted in a significant improvement in erythema and hyperpigmentation both on the forehead and the cheeks, however, more pronounced effects were observed when all the three active compounds were used. Both applied types of treatment considerably increased skin moisture. All the participants (100%) were satisfied with the effects of the treatment. A majority of them reported an improvement in skin hydration, firmness, and elasticity, more uniform skin tone and a reduction of skin redness and wrinkles.

CONCLUSIONS

Topical application of these active compounds resulted in improvement of skin elasticity and flexibility, reduction of wrinkles, hyperpigmentation, erythema, and telangiectasia as well as amelioration of skin tone.

In vivo evaluation of topical ascorbic acid application on skin aging by 50MHz ultrasound

Ascorbic acid (AA) is a powerful antioxidant capable of acting significantly both in the prevention and treatment of the skin aging process. One way to assess the in vivo efficacy of anti-aging treatments is by using the high-frequency ultrasound (HFUS) skin image analysis technique, a non-invasive approach that allows for a new level of evaluating the effectiveness of dermatological and cosmetic products. The aim of the present study was to assess the performance of a topical emulsion of liquid crystalline structures containing AA using the 50 MHz HFUS skin image analysis method. Twenty-five healthy female participants between 35 and 60 years old were included, all of whom randomly applied a placebo formulation and an AA-containing formulation to each forearm, once a day, for 30 days. HFUS measurements were performed before using the products (T0), two hours later (T2h), and after 30 days of use (T30d). The analyzed parameters included total skin, dermal, and epidermal echogenicity; variation and mean thickness of total skin, the epidermis and dermis; and surface roughness. Statistical analyses were performed using the Friedman test, followed by Dunn's test for comparisons of multiple means (α=0.05). A significant increase in total skin and dermal echogenicity was observed after topical AA application. Our findings suggest that collagen synthesis significantly increased after topical therapy with AA, which was responsible for the increment in dermal echogenicity. This study showed, through the HFUS technique, that the topical use of AA promoted dermal redensification after 30 days of application.

Two superior antioxidants: Ferulic acid and ascorbic acid in reducing signs of photoaging-A split-face comparative study

The assessment of the signs of photoaging in mexametric (melanin and erythema index), corneometric (hydration level), and cutometric (elasticity) examination after the treatment with ascorbic acid and ferulic acid. This study was conducted in a group of 20 women aged 39-61 (mean age 54), with Fitzpatrick skin types II and III. The study included a series of eight treatments performed once a week. Two layers of peeling, based on 14% ferulic acid (left half of the face) and 12% l-ascorbic acid serum (right half of the face) were applied. To determine skin parameters: moisture, elasticity, melanin level, and erythema intensity, the Multi Probe Adapter Systems (Courage + Khazaka electronic GmbH, Köln, Germany) were used. Additionally, before and after the series of treatments, photographs were taken with the standardized photographic system Fotomedicus (Elfo®). The results of mexametric measurement for melanin level and erythema intensity were statistically significant (p < 0.0001) for both acids. Slightly greater lightening of the skin was demonstrated for ascorbic acid. The results of corneometric measurement of hydration level for ferulic acid and ascorbic acid were both statistically significant (p < 0.0001). First beneficial changes in improved elasticity could be observed as early as after 8 weeks but the increase in flexibility grew with time (after 12 weeks). These changes affected both acids and all measurement points. The changes in parameters were highly statistically significant (p < 0.0001). Based on the conducted research, it is not possible to state which of the tested acids is more effective in reducing the symptoms of photoaging. Both acids (ascorbic and ferulic), which have a high antioxidant potential, affect the measurable parameters of the skin: pigmentation (melanin index), erythema (erythema index), skin hydration, and elasticity.

Tetrahexyldecyl Ascorbate (THDC) Degrades Rapidly under Oxidative Stress but Can Be Stabilized by Acetyl Zingerone to Enhance Collagen Production and Antioxidant Effects

Tetrahexyldecyl Ascorbate (THDC) is an L-ascorbic acid precursor with improved stability and ability to penetrate the epidermis. The stability and transdermal penetration of THDC, however, may be compromised by the oxidant-rich environment of human skin. In this study, we show that THDC is a poor antioxidant that degrades rapidly when exposed to singlet oxygen. This degradation, however, was prevented by combination with acetyl zingerone (AZ) as a stabilizing antioxidant. As a standalone ingredient, THDC led to unexpected activation of type I interferon signaling, but this pro-inflammatory effect was blunted in the presence of AZ. Moreover, the combination of THDC and AZ increased expression of genes associated with phospholipid homeostasis and keratinocyte differentiation, along with repression of MMP1 and MMP7 expression, inhibition of MMP enzyme activity, and increased production of collagen proteins by dermal fibroblasts. Lastly, whereas THDC alone reduced viability of keratinocytes exposed to oxidative stress, this effect was completely abrogated by the addition of AZ to THDC. These results show that AZ is an effective antioxidant stabilizer of THDC and that combination of these products may improve ascorbic acid delivery. This provides a step towards reaching the full potential of ascorbate as an active ingredient in topical preparations.

Sunscreens and Cosmetic Formulations Containing Ascorbyl Tetraisopalmitate and Rice Peptides for the Improvement of Skin Photoaging: A Double-blind, Randomized Placebo-controlled Clinical Study

Photoprotective formulations containing substances with antioxidant properties in combination have been used as a strategy for the improvement of photoaged skin conditions. However, there is a lack of studies evaluating the clinical efficacy of these substances in young women with signs of photoaging. Thus, the objective of the present study was to evaluate the clinical efficacy of sunscreens and cosmetic formulations containing ascorbyl tetraisopalmitate and rice peptides for the improvement of skin photoaging in young women. A double-blind, randomized placebo-controlled clinical efficacy study was conducted on 60 female subjects aged 20-30 years with skin changes related to photoaging and without photoprotective habits. The hydrolipidic layer conditions and structural and morphological characteristics of the skin were evaluated by biophysical and skin imaging techniques. The results showed that the daily use of the formulations under study improved the skin conditions by increasing skin hydration and dermis echogenicity. In addition, the application of the active substances reduced skin hyperpigmentation and increased epidermal cell renewal. In summary, the present study showed the importance of daily application of sunscreens and formulations with antioxidant properties for the prevention and attenuation of skin changes related to photoaging in young women.

Formulation and evaluation of wound healing activity of Elaeis guineensis Jacq leaves in a Staphylococcus aureus infected Sprague Dawley rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants are crucial to healing numerous illnesses. Elaeis guineensis Jacq (family Arecaceae) is a medicinal plant traditionally used for the treatment of wounds.

AIM OF THE STUDY

However, there are no scientific reports documented on the wound healing activities of this plant against Staphylococcus aureus infections in the Sprague Dawley male rat model. Thus, the present study was conducted to evaluate the wound healing potential of E. guineensis extract leaves.

MATERIALS AND METHODS

The crude extract was prepared in 10% (w/w) ointment and evaluated for wound healing activity using excision and infected wound models in Sprague Dawley rats. The wound healing activity was evaluated from wound closure rate, CFU reduction, histological analysis of granulation tissue and matrix metalloprotease expression.

RESULTS

The results show that the E. guineensis extract has potent wound healing ability, as manifest from improved wound closure and tissue regeneration supported by histopathological parameters. Assessment of granulation tissue every fourth day showed a significant reduction in the microbial count. The expression of matrix metalloproteinases was well correlated with the other results, hence confirming E. guineensis wound healing activity's effectiveness.

CONCLUSIONS

E. guineensis enhanced infected wound healing in rats, thus supporting its traditional use.

Improvement of Cell Proliferation and Antioxidant Activity of Silymarin in Hair Follicles Dermal Papillae Isolated from the Human Scalp: Comparison with Vitamin C Effects

Introduction:

Nowadays, hair loss is becoming a major problem for a large number of people. The main factors affecting hair growth include racial, gender, genetics, and hormonal. Furthermore, environment, physiology, and nutrition are the tools that are affecting hair growth.

Materials and Methods:

This article analyses the effects of silymarin and Vitamin C on the proliferation of dermal papilla cells (DPCs), COX2, inducible nitric oxide synthase (iNOS), total anti-oxidant capacity (TAC), and reactive oxygen species (ROS). The DPCs of the hair follicle treated by 50 and 100 μM of silymarin and 100 μM of Vitamin C on days 2, 7, and 14.

Results:

A comparatively effect of silymarin and Vitamin C demonstrated that Vitamin C is more effective in the stimulation of dermal papillae in cell culture. Furthermore, the stimulation effects of silymarin are attributed to its antioxidant activity of the cells.

Conclusion:

The overall result shows that cell proliferation and TAC significantly increased. However, iNOS, ROS, and COX2 levels were decreased.

Skin Health from the Inside Out

The skin is the main interface between the body and the environment, providing a biological barrier against an array of chemical and physical pollutants (e.g., ultraviolet light, ozone, etc.). Exposure of the skin to these outdoor stressors generates reactive oxygen species (ROS), which can overwhelm the skin's endogenous defense systems (e.g., catalase, vitamins C and E, etc.), resulting in premature skin aging due to the induction of DNA damage, mitochondrial damage, lipid peroxidation, activation of inflammatory signaling pathways, and formation of protein adducts. In this review, we discuss how topical application of antioxidants, including vitamins C and E, carotenoids, resveratrol, and pycnogenol, can be combined with dietary supplementation of these antioxidant compounds in addition to probiotics and essential minerals to protect against outdoor stressor-induced skin damage, including the damage associated with aging.

Evolution of the use of antioxidants in anti-ageing cosmetics

OBJECTIVE

Skin health and beauty are a cornerstone of general well-being in humans. Anti-ageing cosmetics are used to provide a healthy and youthful appearance. Among the different cosmetic actives, antioxidants are incorporated in anti-ageing products due to their beneficial effects in preventing and minimizing the signs of skin ageing. This work aims to understand how anti-ageing formulations changed in the past 7 years regarding pure antioxidants composition.

METHODS

Data were collected from anti-ageing formulations commercialized in main stores and pharmacies in the Portuguese market. The study started on 2011 and was updated with products launched or whose composition has been renewed on 2013, 2015 or 2018.

RESULTS

Ascorbic acid and tocopherol and their derivatives were consistently the most used antioxidants in anti-ageing formulations; followed by niacinamide and retinyl palmitate. Seven ascorbic acid derivatives are currently used in anti-ageing formulations while only three tocopherol derivatives were identified in this study. Several combinations of antioxidants were routinely found, mainly tocopherol (or tocopherol derivatives) with other antioxidants and tocopherol with tocopherol derivatives. We have not identified emerging antioxidants with great impact in anti-ageing formulations even though niacinamide and retinyl palmitate exhibited over 10% more usage in 2018.

CONCLUSION

This insight is relevant to the cosmetic industry providing a better understanding of the scientific-based formulation of modern cosmetics and supports the need for innovative antioxidants in anti-ageing cosmetics.

Ascorbic acid encapsulated into negatively charged liposomes exhibits increased skin permeation, retention and enhances collagen synthesis by fibroblasts

Ascorbic acid (AA) is widely used in cosmetic formulations due to its antioxidant property and ability to increase collagen synthesis. Here, we encapsulated AA in vesicles with different lipid compositions. Negative liposome charge favored AA skin retention, with accumulation of 37 ± 12 and 74 ± 23 μg/cm² in the epidermis and dermis, respectively, after 6 hours. Drug flux was influenced by the formulation composition, and both the presence of cholesterol and the liposomes surface charge were able to increase the amount of AA crossing the skin. The formulation was stable for at least 30 days and promoted a 7-fold increase in flux compared to free AA. Additionally, liposomes were able to interact better with keratinocytes and fibroblasts membranes. In vitro efficacy studies demonstrated that associating AA to these liposomes resulted in increased effectiveness of type I collagen synthesis by fibroblasts and regeneration of UVA-induced damage in keratinocytes. Our results demonstrate the applicability of AA-negatively charged liposomes in promoting AA cutaneous permeation and increasing the retention and flux of this molecule in the skin. This formulation also increased AA stability and effectiveness, opening new perspectives for its application in view of reducing certain skin ageing outcomes.

Skin care and rejuvenation by cosmeceutical facial mask

Skin health is an important aspect of aesthetics. Dermatologists and scientists try to develop novel methods and materials to fulfill this aim. Facial cosmetics keep skin moist and remove sebum from the skin to maintain proper skin health. The use of suitable cosmetics according to the facial skin type results in healthy skin. Facial masks are the most prevalent cosmetic products utilized for skin rejuvenation. Facial masks are divided into four groups: (a) sheet masks; (b) peel-off masks; (c) rinse-off masks; and (d) hydrogels. Each of these has some advantages for specific skin types based on the ingredients used. The following article presents the available information about the facial mask. Also, we have focused on the facial masks available in the market. Despite several developments in this field, extensive research is required for performing successful and precise clinical trials in the future. Further improvements would enable the researchers to develop new products in this field. In this review, we present the most recent breakthroughs in the field of skin care and rejuvenation by cosmeceutical facial mask. This information is valuable to get the picture of the latest trends and also helpful for clinicians and related manufacturing companies.

Novel reverse electrodialysis-driven iontophoretic system for topical and transdermal delivery of poorly permeable therapeutic agents

Topical and transdermal drug delivery has great potential in non-invasive and non-oral administration of poorly bioavailable therapeutic agents. However, due to the barrier function of the stratum corneum, the drugs that can be clinically feasible candidates for topical and transdermal delivery have been limited to small-sized lipophilic molecules. Previously, we fabricated a novel iontophoretic system using reverse electrodialysis (RED) technology (RED system). However, no study has demonstrated its utility in topical and/or transdermal delivery of poorly permeable therapeutic agents. In this study, we report the topical delivery of fluorescein isothiocyanate (FITC)-hyaluronic acid (FITC-HA) and vitamin C and the transdermal delivery of lopinavir using our newly developed RED system in the in vitro hairless mouse skin and in vivo Sprague-Dawley rat models. The RED system significantly enhanced the efficiency of topical HA and vitamin C and transdermal lopinavir delivery. Moreover, the efficiency and safety of transdermal delivery using the RED system were comparable with those of a commercial ketoprofen patch formulation. Thus, the RED system can be a potential topical and transdermal delivery system for various poorly bioavailable pharmaceuticals including HA, vitamin C, and lopinavir.

The Roles of Vitamin C in Skin Health

The primary function of the skin is to act as a barrier against insults from the environment, and its unique structure reflects this. The skin is composed of two layers: the epidermal outer layer is highly cellular and provides the barrier function, and the inner dermal layer ensures strength and elasticity and gives nutritional support to the epidermis. Normal skin contains high concentrations of vitamin C, which supports important and well-known functions, stimulating collagen synthesis and assisting in antioxidant protection against UV-induced photodamage. This knowledge is often used as a rationale for the addition of vitamin C to topical applications, but the efficacy of such treatment, as opposed to optimising dietary vitamin C intake, is poorly understood. This review discusses the potential roles for vitamin C in skin health and summarises the in vitro and in vivo research to date. We compare the efficacy of nutritional intake of vitamin C versus topical application, identify the areas where lack of evidence limits our understanding of the potential benefits of vitamin C on skin health, and suggest which skin properties are most likely to benefit from improved nutritional vitamin C intake.

Microneedles for Transdermal Biosensing: Current Picture and Future Direction

A novel trend is rapidly emerging in the use of microneedles, which are a miniaturized replica of hypodermic needles with length-scales of hundreds of micrometers, aimed at the transdermal biosensing of analytes of clinical interest, e.g., glucose, biomarkers, and others. Transdermal biosensing via microneedles offers remarkable opportunities for moving biosensing technologies and biochips from research laboratories to real-field applications, and envisages easy-to-use point-of-care microdevices with pain-free, minimally invasive, and minimal-training features that are very attractive for both developed and emerging countries. In addition to this, microneedles for transdermal biosensing offer a unique possibility for the development of biochips provided with end-effectors for their interaction with the biological system under investigation. Direct and efficient collection of the biological sample to be analyzed will then become feasible in situ at the same length-scale of the other biochip components by minimally trained personnel and in a minimally invasive fashion. This would eliminate the need for blood extraction using hypodermic needles and reduce, in turn, related problems, such as patient infections, sample contaminations, analysis artifacts, etc. The aim here is to provide a thorough and critical analysis of state-of-the-art developments in this novel research trend, and to bridge the gap between microneedles and biosensors.

The role of vitamin C in pushing back the boundaries of skin aging: an ultrasonographic approach

Background

Imagistic methods stand as modern, non-invasive, and objective means of assessing the impact of topical cutaneous therapies.

Objective

This study focuses on the evaluation, by high-frequency ultrasound, of the cutaneous changes induced by topical use of a vitamin C complex at facial level.

Methods

A vitamin C-based solution/Placebo moisturizer cream was applied at facial level of 60 healthy female subjects according to a predetermined protocol. Ultrasonographic images (Dermascan C, 20 MHz) were taken from zygomatic level initially, at 40 and 60 days after therapy. The following parameters were assessed for every subject: thickness of the epidermis and dermis (mm), the number of low (LEP), medium (MEP), high echogenic pixels (HEP), and the number of LEP in the upper dermis/lower dermis (LEPs/LEPi).

Results

LEP decreased significantly in all age categories during and after therapy, but especially in the first 2 age intervals, up to the age of 50 (P=0.0001). MEP and HEP, pixel categories that quantify protein synthesis also had an age-dependent evolution in the study, increasing significantly in all age categories but most of all in the first age interval (P=0.002). Our ultrasonographic data suggest that collagen synthesis increased significantly after topical vitamin C therapy, and is responsible for the increase in MEP and HEP and consequent decrease of the LEP.

Conclusion

Our study shows that topically applied vitamin C is highly efficient as a rejuvenation therapy, inducing significant collagen synthesis in all age groups with minimal side effects.

Blistering time as a parameter for the strength of dermoepidermal adhesion: a systematic review and meta-analysis

Skin ageing is associated with a flattening of the dermoepidermal junction and a less effective anchoring system, predisposing to bulla formation, trauma and shear-type injuries. An artificial and controlled technique for standardized dermoepidermal separation is the suction blister method, whereby the strength of dermoepidermal adhesion is characterized by blistering time. To identify and quantify influencing factors on blistering time in healthy humans. A search in the Medline and Embase databases (1946 to June 2014) and in reference lists was conducted. In total, results of 146 suction blister experiments in 3418 individuals reported in 59 publications were analysed. The median blister diameter was 6 mm (IQR 5-6) and the median suction pressure was -210 mmHg (IQR -200 to -300), resulting in a median blistering time of 75 min (IQR 48-120). In the multivariate model, skin temperature and age were the strongest predictors for suction blistering time (P < 0·001, R(2) adjusted  = 0·707). This strong association between temperature and suction blistering indicates that the dermoepidermal junction loses its strength with increasing skin temperature. This finding supports the practice of skin and tissue cooling to prevent injuries. The increased vulnerability of the skin seems to exist irrespectively of applied mechanical loads. We conclude that blistering time is an important and clinically relevant (outcome) parameter measuring the structural and mechanical integrity of deeper cutaneous layers.

An antiaging skin care system containing alpha hydroxy acids and vitamins improves the biomechanical parameters of facial skin

Background

The demand for antiaging products has dramatically increased in recent years, driven by an aging population seeking to maintain the appearance of youth. This study investigates the effects of an antiaging skin care system containing alpha hydroxy acids (AHAs) in conjunction with vitamins B₃, C, and E on the biomechanical parameters of facial skin.

Methods

Fifty two volunteers followed an antiaging skin care regimen comprising of cleanser, eye cream, day moisturizer, and night moisturizer for 21 days. Wrinkle depth (R_y) and skin roughness (R_a) were measured by skin surface profilometry of the crow’s feet area, and skin elasticity parameters R2 (gross elasticity), R5 (net elasticity), R6 (viscoelastic portion), and R7 (recovery after deformation) were determined for facial skin by cutometer, preapplication and after 7, 14, and 21 days. Volunteers also completed a self-assessment questionnaire.

Results

Compared to baseline, R_y and R_a significantly improved by 32.5% (P<0.0001) and 42.9% (P<0.0001), respectively, after 21 days of antiaging skin care treatment. These results were observed by the volunteers with 9 out of 10 discerning an improvement in skin texture and smoothness. Compared to baseline, R2 and R5 significantly increased by 15.2% (P<0.0001) and 12.5% (P=0.0449), respectively, while R6 significantly decreased by 17.7% (P<0.0001) after 21 days. R7 increased by 9.7% after 21 days compared to baseline but this was not significant over this time period.

Conclusion

An antiaging skin care system containing AHAs and vitamins significantly improves the biomechanical parameters of the skin including wrinkles and skin texture, as well as elasticity without significant adverse effects.

Changes in dermal papilla structures due to aging in the facial cheek region

BACKGROUND/PURPOSE

In the past, it has been possible to measure the dermal papilla structures which are undulations between the epidermis and dermis by noninvasive method. However, almost all of previous studies were not intended to measure facial skin but another site of body. Here, we investigated age-dependent alterations for dermal papilla structures in the facial cheek region after elucidating the difference of characteristics between the body site.

METHODS

The surface of the dermis was observed under scanning electron microscope (SEM) using face and abdominal skin biopsy samples. A total of 90 Japanese women were investigated by in vivo confocal laser microscope (CLSM). The number and the shape in the horizontal cross-sectional images of the dermal papilla were analyzed.

RESULTS

The facial skin had different characteristics in comparison to the abdominal skin by SEM observation. Under CLSM observation, we found abnormal dermal papilla structures which were accompanied by spots or enlarged pore areas and eliminated these structures from our analysis. We revealed a decrease in the number of normal dermal papilla structures with age and large individual differences at younger ages.

CONCLUSION

We found abnormal dermal papilla structures and differences in the dermal papilla structures between face and other body site. With these taken into consideration, we could precisely investigate the aging alteration of normal dermal papilla structures in the face.

Confocal laser scanning microscopy in vivo for diagnosing melanocytic skin neoplasms

The authors discuss the use of confocal laser scanning microscopy in vivo (CLSM) for diagnosing melanocytic skin neoplasms and its value for early diagnostics of melanoma. CLSM is an innovation noninvasive visual examination method for real-time multiple and painless examinations of the patient’s skin without injuring the skin integument. The method ensures early diagnostics of skin melanomas with high sensitivity and specificity, which makes it possible to use CLSM for screening melanocytic skin neoplasms for the sake of the early onset of treatment to save patient life and health.

An integral topical gel for cellulite reduction: results from a double-blind, randomized, placebo-controlled evaluation of efficacy

BACKGROUND

Cellulite is a serious cosmetic concern for most of the 90% of women affected by it.

OBJECTIVE

To assess the clinical efficacy of a complex integral anti-cellulite gel.

METHODS

This double-blind, randomized, placebo-controlled study involved 44 healthy women, aged 25-55 years. Subjects had a normal to slightly overweight body mass index and presented slight to moderate cellulite on their thighs, buttocks, and/or hips at baseline. Subjects were randomly assigned to either the treated or placebo group and accordingly applied the active product or placebo on their hips, stomach, buttocks, and thighs, twice daily for 3 months. Skin tonicity, orange-peel aspect, and stubborn cellulite were assessed at day 0, 28, 56, and 84. A self-evaluation questionnaire was completed by all volunteers.

RESULTS

At the end of the study, an average of 81% of the subjects applying the active product presented improvement in their cellulite condition versus 32% for the placebo group (all descriptors and sites combined). At day 84, skin tonicity, orange-peel appearance, and stubborn cellulite were improved in a significant manner (P<0.05) over placebo, on all studied areas. Skin tonicity improved on average by +41% for buttocks, +35% for hips, and +31% for thighs. Orange peel appearance was reduced on average by -25% for buttocks, -22% for hips, and -22% for thighs. Stubborn cellulite was reduced on average by -19% for buttocks, -24% for hips, and -22% for thighs. Circumference measurements decreased in a significant manner (P<0.05) over placebo, for the abdomen (average value of -1.1 cm) and thighs (average value of -0.8 cm). The product was well tolerated and perceived by the volunteers themselves as better performing than placebo on all criteria.

CONCLUSION

All results validate the efficacy of the present integral formulation to significantly reduce signs of cellulite and reshape the silhouette.

In vivo quantification of epidermis pigmentation and dermis papilla density with reflectance confocal microscopy: variations with age and skin phototype

Reflectance confocal microscopy (RCM) may help to quantify variations of skin pigmentation induced by different stimuli such as UV radiation or therapeutic intervention. The objective of our work was to identify RCM parameters able to quantify in vivo dermis papilla density and epidermis pigmentation potentially applicable in clinical studies. The study included 111 healthy female volunteers with phototypes I-VI. Photo-exposed and photo-protected anatomical sites were imaged. The effect of age was also assessed. Four epidermis components were specifically investigated: stratum corneum, stratum spinosum, basal epidermal layer and dermo-epidermal junction. Laser power, diameter of corneocytes and upper spinous keratinocytes, brightness of upper spinous and interpapillary spinous keratinocytes, number of dermal papillae and papillary contrast were systematically assessed. Papillary contrast measured at the dermo-epidermal junction appeared to be a reliable marker of epidermis pigmentation and showed a strong correlation with skin pigmentation assessed clinically using the Fitzpatrick's classification. Brightness of upper spinous and interpapillary spinous keratinocytes was not influenced by the skin phototype. The number of dermal papillae was significantly lower in subjects with phototypes I-II as compared with darker skin subjects. A dramatic reduction in the number of dermal papillae was noticed with age, particularly in subjects with fair skin. The method presented here provides a new in vivo investigation tool for quantification of dermis papilla density and epidermal pigmentation. Papillary contrast measured at the dermo-epidermal junction may be selected as a marker of skin pigmentation for evaluation in clinical studies.

Wound healing activity of Elaeis guineensis leaf extract ointment

Elaeis guineensis of the Arecaceae family is widely used in the traditional medicine of societies in West Africa for treating various ailments. To validate the ethnotherapeutic claims of the plant in skin diseases, wound healing activity was studied. The results showed that E. guineensis leaf extract had potent wound healing capacity as evident from the better wound closure (P < 0.05), improved tissue regeneration at the wound site, and supporting histopathological parameters pertaining to wound healing. Matrix metalloproteinases expression correlated well with the results thus confirming efficacy of E. guineensis in the treatment of the wound. E. guineensis accelerated wound healing in rats, thus supporting its traditional use. The result of this study suggested that, used efficiently, oil palm leaf extract is a renewable resource with wound healing properties.

Vitamins and cutaneous wound healing

BACKGROUND

Vitamins have long been thought to modulate the various stages of wound healing through a variety of proposed mechanisms. Our goal was to investigate relevant studies examining the role of different vitamins in wound healing.

METHODS

MEDLINE, Cochrane Database of Systematic Reviews, and Google Scholar were searched for basic science and clinical studies examining the role of vitamins as adjuncts in wound healing.

RESULTS

Mechanisms of action for each of the vitamins are reviewed. It was suggested by many of the studies that the major vitamins A, C, E, D, K, and B have demonstrated utility as adjuncts in wound care in basic science and clinical trials.

CONCLUSION

There is a vast amount of literature on the effect of vitamins on wound healing at the basic science level. Further understanding and controlled trials will help better understand how to utilize vitamins in wound care.

DECLARATION OF INTEREST

None.

Surface-modified microprojection arrays for intradermal biomarker capture, with low non-specific protein binding

Minimally invasive biosensors are of great interest for rapid detection of disease biomarkers for diagnostic screening at the point-of-care. Here we introduce a device which extracts disease-specific biomarkers directly from the upper dermis, without the needle and syringe or resource-intensive blood processing. Using antigen-specific antibodies raised in mice as a model system, we confirm the analytical specificity and sensitivity of the antibody capture and extraction in comparison to the conventional methods based on needle/syringe blood draw followed by processing and antigen-specific ELISAs.

Wound healing potential of Elaeis guineensis Jacq leaves in an infected albino rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Elaeis guineensis Jacq (Arecaceae) is one of the plants that are central to the lives of traditional societies in West Africa. It has been reported as a traditional folkloric medicine for a variety of ailments. The plant leaves are also used in some parts of Africa for wound healing, but there are no scientific reports on any wound healing activity of the plant.

AIM OF THE STUDY

To investigate the effects of E. guineensis leaf on wound healing activity in rats.

METHODS

A phytochemical screening was done to determine the major phytochemicals in the extract. The antimicrobial activity of the extract was examined using the disk diffusion technique and broth dilution method. The wound healing activity of leaves of E. guineensiswas studied by incorporating the methanolic extract in yellow soft paraffin in concentration of 10% (w/w). Wound healing activity was studied by determining the percentage of wound closure, microbial examination of granulated skin tissue and histological analysis in the control and extract treated groups.

RESULTS

Phytochemical screening reveals the presence of tannins, alkaloids, steroids, saponins, terpenoids, and flavonoids in the extract. The extract showed significant activity against Candida albicans with an MIC value of 6.25 mg/mL. The results show that the E. guineensis extract has potent wound healing capacity, as evident from better wound closure, improved tissue regeneration at the wound site, and supporting histopathological parameters pertaining to wound healing. Assessment of granulation tissue every fourth day showed a significant reduction in microbial count.

CONCLUSIONS

E. guineensis accelerated wound healing in rats, thus supporting this traditional use.

Ascorbic acid for the healing of skin wounds in rats

BACKGROUND: Healing is a complex process that involves cellular and biochemical events. Several medicines have been used in order to shorten healing time and avoid aesthetic damage. OBJECTIVE: to verify the topical effect of ascorbic acid for the healing of rats' skin wounds through the number of macrophages, new vessels and fibroblast verifications in the experimental period; and analyse the thickness and the collagen fibre organization in the injured tissue. METHODS: Male Rattus norvegicus weighing 270 ± 30 g were used. After thionembutal anesthesia, 15 mm transversal incisions were made in the animals' cervical backs. They were divided into two groups: Control Group (CG, n = 12) - skin wound cleaned with water and soap daily; Treated Group (TG, n = 12) - skin wound cleaned daily and treated with ascorbic acid cream (10%). Samples of skin were collected on the 3rd, 7th and 14th days. The sections were stained with hematoxylin-eosin and picrosirius red for morphologic analysis. The images were obtained and analysed by a Digital Analyser System. RESULTS: The ascorbic acid acted on every stage of the healing process. It reduced the number of macrophages, increased the proliferation of fibroblasts and new vessels, and stimulated the synthesis of thicker and more organized collagen fibres in the wounds when compared to CG. CONCLUSION: Ascorbic acid was shown to have anti-inflammatory and healing effects, guaranteeing a suiTable environment and conditions for faster skin repair.

Comparison of epidermal morphologic response to commercial antiwrinkle agents in the hairless mouse

BACKGROUND

A large number of commercial antiwrinkle and antiaging compounds are available to consumers for rejuvenation of facial skin ravaged by age or solar radiation. Experimental data on the histological effects of these commercial products in laboratory models are sparse.

OBJECTIVES

To compare the efficacy of topical application of five commercially available antiaging compounds (retinoic acid, glycolic acid, vitamin C, estrogen, and soy) on the dorsal skin.

METHODS AND MATERIALS

The effects were examined using light microscopic analysis of the epidermis in the normal nonirradiated hairless mouse. The agents were applied daily to dorsal tattooed areas for 2 weeks before histological assessment; neighboring untreated surface areas were used as control. Morphometric measurements of total epidermal width, nuclear volume of keratinocytes in three layers, and index of proliferating cell nuclear antigen according to immunohistochemistry were obtained and statistically analyzed.

RESULTS

Significant histomorphometric effects were noticed with all five agents, but more pronounced changes were obtained with glycolic acid, estrogen, and retinoic acid product.

CONCLUSIONS

These baseline data will be useful for future studies on the effect of ultraviolet radiation to cause photoaging and reparative effects of similar agents in this animal. The information contained in the report may provide guidelines to consumers and clinicians.

Intrinsic and extrinsic factors in skin ageing: a review

As the proportion of the ageing population in industrialized countries continues to increase, the dermatological concerns of the aged grow in medical importance. Intrinsic structural changes occur as a natural consequence of ageing and are genetically determined. The rate of ageing is significantly different among different populations, as well as among different anatomical sites even within a single individual. The intrinsic rate of skin ageing in any individual can also be dramatically influenced by personal and environmental factors, particularly the amount of exposure to ultraviolet light. Photodamage, which considerably accelerates the visible ageing of skin, also greatly increases the risk of cutaneous neoplasms. As the population ages, dermatological focus must shift from ameliorating the cosmetic consequences of skin ageing to decreasing the genuine morbidity associated with problems of the ageing skin. A better understanding of both the intrinsic and extrinsic influences on the ageing of the skin, as well as distinguishing the retractable aspects of cutaneous ageing (primarily hormonal and lifestyle influences) from the irretractable (primarily intrinsic ageing), is crucial to this endeavour.

In vivo reflectance-mode confocal microscopy in clinical dermatology and cosmetology

In vivo reflectance confocal microscopy (RCM) is a non-invasive imaging tool that allows real-time visualization of cells and structures in living skin with near histological resolution. RCM has been used for the assessment of benign and malignant lesions, showing great potential for applications in basic skin research and clinical dermatology. RCM also reveals dynamic changes in the skin over time and in response to specific stimuli, like ultraviolet exposure, which makes it a promising tool in cosmetology, as it allows repetitive sampling without biopsy collection, causing no further damage to the areas under investigation. This review summarizes the latest advances in RCM, and its applications in the characterization of both normal and pathological skin.

Triphala promotes healing of infected full-thickness dermal wound

BACKGROUND

Infection is a major problem in the management of wounds. Even though the development of synthetic antimicrobial agents persists, drug resistance and toxicity hinder their way. Many plants with multi-potent pharmaceutical activities may offer better treatment options, and Triphala (dried fruits of Terminalia chebula, Terminalia bellirica, and Phyllanthus emblica) are potential formulations evaluated for healing activity on infected wound as it possesses numerous activities.

MATERIALS AND METHODS

Alcoholic extract of Triphala has shown in vitro antimicrobial activity against wound pathogens such as Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pyogenes. An ointment was prepared from the Triphala extract (10% w/w) and assessed for in vivo wound healing on infected rat model by rate of healing, bacterial count, biochemical analysis, and expression of matrix metalloproteinases.

RESULTS

The treated group has shown significantly improved wound closure. Assessment of granulation tissue on every fourth day showed significant reduction in bacterial count with significant level of collagen, hexosamine, uronic acid, and superoxide dismutase in the treated group (P < 0.01). Reduction of matrix metalloproteinase expression observed in the treated group by gelatin zymography and immunoblotting confirms our in vivo assessment.

CONCLUSIONS

The above results showed the antibacterial, wound healing, and antioxidant activities of Triphala ointment, necessary for the management of infected wounds. Active principles of the Triphala may be further evaluated and used as an excellent therapeutic formulation for infected wounds.

Acute ascorbate supplementation alone or combined with arginase inhibition augments reflex cutaneous vasodilation in aged human skin

Full expression of reflex cutaneous vasodilation (VD) is dependent on nitric oxide (NO) and is attenuated in older humans. NO may be decreased by an age-related increase in reactive oxygen species or a decrease in l-arginine availability via upregulated arginase. The purpose of this study was to determine the effect of acute antioxidant supplementation alone and combined with arginase inhibition on reflex VD in aged skin. Eleven young (Y; 22 ± 1 yr) and 10 older (O; 68 ± 1 yr) human subjects were instrumented with four intradermal microdialysis (MD) fibers. MD sites were control (Co), NO synthase inhibited (NOS-I), l-ascorbate supplemented (Asc), and Asc + arginase-inhibited (Asc + A-I). After baseline measurements, subjects underwent whole body heating to increase oral temperature (Tor) by 0.8°C. Red blood cell flux was measured by using laser-Doppler flowmetry, and cutaneous vascular conductance (CVC) was calculated (CVC = flux/mean arterial pressure) and normalized to maximal (CVCmax). VD during heating was attenuated in O (Y: 37 ± 3 vs. O: 28 ± 3% CVCmax; P < 0.05). NOS-I decreased VD in both groups compared with Co (Y: 20 ± 4; O: 15 ± 2% CVCmax; P < 0.05 vs. Co within group). Asc and Asc + A-I increased VD beyond Co in O (Asc: 35 ± 4% CVCmax; Asc + A-I: 41 ± 3% CVCmax; P < 0.001) but not in Y (Asc: 36 ± 3% CVCmax; Asc + A-I: 40 ± 5% CVCmax; P > 0.05). Combined Asc + A-I resulted in a greater increase in VD than Asc alone in O ( P = 0.001). Acute Asc supplementation increased reflex VD in aged skin. Asc combined with arginase inhibition resulted in a further increase in VD above Asc alone, effectively restoring CVC to the level of young subjects.