Skin collagen changes related to age and hormone replacement therapy

Taurine Prevents Impairments in Skin Barrier Function and Dermal Collagen Synthesis Triggered by Sleep Deprivation-Induced Estrogen Circadian Rhythm Disruption

Sleep deprivation is a prevalent issue that disrupts the circadian rhythm of estrogen, particularly estradiol, thereby significantly affecting women's skin health and appearance. These disruptions can impair skin barrier functionality and decrease dermal collagen synthesis. In this study, our results demonstrate that topical taurine supplementation promotes the expression of tight junction (TJ)-related proteins and enhances collagen production, effectively restoring skin homeostasis in sleep-deprived female mice. Mechanistically, taurine upregulates the expression of TMEM38B, a gene encoding the TRIC-B trimeric cation channel, resulting in increased intracellular calcium ion levels. This, in turn, promotes the upregulation of TJ-related proteins, such as ZO-1, occludin, and claudin-11 in epidermal cells, while also enhancing the expression of type III collagen in fibroblasts, thus restoring skin homeostasis. These findings suggest that taurine may serve as an alternative to estradiol, effectively improving skin homeostasis disrupted by sleep deprivation while mitigating the potential risks associated with exogenous estrogen supplementation. Collectively, these results provide preliminary insights into the protective mechanisms of taurine against sleep deprivation-induced skin impairments and establish a foundation for its potential application in treating skin conditions related to estrogen imbalances, such as skin aging in menopausal women.

Endocrine Controls of Skin Aging

Skin is the largest organ of the human body and undergoes both intrinsic (chronological) and extrinsic aging. While intrinsic skin aging is driven by genetic and epigenetic factors, extrinsic aging is mediated by external threats such as UV irradiation or fine particular matters, the sum of which is referred to as exposome. The clinical manifestations and biochemical changes are different between intrinsic and extrinsic skin aging, albeit overlapping features exist, eg, increased generation of reactive oxygen species, extracellular matrix degradation, telomere shortening, increased lipid peroxidation, or DNA damage. As skin is a prominent target for many hormones, the molecular and biochemical processes underlying intrinsic and extrinsic skin aging are under tight control of classical neuroendocrine axes. However, skin is also an endocrine organ itself, including the hair follicle, a fully functional neuroendocrine "miniorgan." Here we review pivotal hormones controlling human skin aging focusing on IGF-1, a key fibroblast-derived orchestrator of skin aging, of GH, estrogens, retinoids, and melatonin. The emerging roles of additional endocrine players, ie, α-melanocyte-stimulating hormone, a central player of the hypothalamic-pituitary-adrenal axis; members of the hypothalamic-pituitary-thyroid axis; oxytocin, endocannabinoids, and peroxisome proliferator-activated receptor modulators, are also reviewed. Until now, only a limited number of these hormones, mainly topical retinoids and estrogens, have found their way into clinical practice as anti-skin aging compounds. Further research into the biological properties of endocrine players or its derivatives may offer the development of novel senotherapeutics for the treatment and prevention of skin aging.

Restoration of the Ultrastructural Integrity of the Dermal Collagen Network by 12-Week Ingestion of Special Collagen Peptides

INTRODUCTION

This pilot study investigated the effects of a 12-week administration of a nutritional supplement containing special collagen peptides on the structural and molecular properties of the collagen fiber network in the human skin. For the assessments, the suction blister method and electron microscopical comparisons were used.

METHODS

Three suction blisters were generated on the inner forearm of each test subject before and after the 12-week administration of the nutritional supplement. High-resolution scanning electron microscopy (SEM) was employed to meticulously investigate the structural characteristics of the skin's collagen network, including the length and diameter of collagen fibers within the suction blister roof. Furthermore, the analysis included immunohistochemistry and fluorescence light microscopy to study hyaluronic acid within the extracellular matrix. Additional assessments encompassed changes in various epidermal parameters. Nine female participants within the age range of 43.7-61.8 years (mean: 52.5 ± 5.9 years) completed the study in accordance with the study protocol.

RESULTS

Compared with baseline, the 12-week supplementation regimen led to a statistically significant average increase in the collagen fiber network size of 34.56% (p < 0.0001). Additionally, collagen fiber cross-linking and fiber length were substantially increased. The ingestion of the supplement also resulted in an 18.08% elevation in epidermal hyaluronic acid concentration (p < 0.0001). No adverse events were recorded during the study.

CONCLUSION

Using an innovative approach, this study demonstrated the ability of a targeted nutritional supplement to effectively restore the ultrastructural integrity of the dermal collagen network, which is typically disrupted by the natural aging process of the skin. These findings not only corroborate existing data regarding the positive effects of oral collagen peptides on skin structure and function but also contribute to our understanding of ultrastructural morphological aspects of changes in the skin's collagen network. Supplementation can induce regeneration of the collagen fiber network in the human skin.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register, DRKS-ID DRKS00034161- Date of registration: 06.05.2024, retrospectively registered.

A Positive Feedback Loop Exists between Estradiol and IL-6 and Contributes to Dermal Fibrosis

Systemic sclerosis (SSc) is characterized by dermal fibrosis with a female predominance, suggesting a hormonal influence. Patients with SSc have elevated interleukin (IL)-6 levels, and post-menopausal women and older men also have high estradiol (E2) levels. In the skin, IL-6 increases the enzymatic activity of aromatase, thereby amplifying the conversion of testosterone to E2. Therefore, we hypothesized that an interplay between E2 and IL-6 contributes to dermal fibrosis. We used primary dermal fibroblasts from healthy donors and patients with diffuse cutaneous (dc)SSc, and healthy donor skin tissues stimulated with recombinant IL-6 and its soluble receptor (sIL-6R) or E2. Primary human dermal fibroblasts and tissues from healthy donors stimulated with IL-6+sIL-6R produced E2, while E2-stimulated dermal tissues and fibroblasts produced IL-6. Primary dermal fibroblasts from healthy donors treated with IL-6+sIL-6R and the aromatase inhibitor anastrozole (ANA) and dcSSc fibroblasts treated with ANA produced less fibronectin (FN), type III collagen A1 (Col IIIA1), and type V collagen A1 (Col VA1). Finally, dcSSc dermal fibroblasts treated with the estrogen receptor inhibitor fulvestrant also generated less FN, Col IIIA1, and Col VA1. Our data show that IL-6 exerts its pro-fibrotic influence in human skin in part through E2 and establish a positive feedback loop between E2 and IL-6.

The Effects of Dietary Supplementation with Collagen and Vitamin C and Their Combination with Hyaluronic Acid on Skin Density, Texture and Other Parameters: A Randomised, Double-Blind, Placebo-Controlled Trial

Collagen dietary supplements are becoming increasingly popular as a means to reduce signs of skin ageing. The objective of this three-way, randomised, placebo-controlled, double-blind study was to examine and contrast the effects of dietary supplementation with a daily dose of 5 g hydrolysed collagen with 80 mg of vitamin C (CP product) and their combination with 30 mg of hyaluronic acid (CPHA product) over 16 weeks. Validated methods were utilised for the objective evaluation of skin parameters. In total, 87 subjects (women, 40-65 years) completed the entire trial, distributed across the groups as follows: placebo group (n = 29), CPHA group (n = 28), and CP group (n = 30). The results showed beneficial effects of both test products, with notable enhancements in dermis density, skin texture, and a reduction in the severity of wrinkles. In contrast, the administration of either of the products did not yield any significant impacts on skin elasticity or hydration. Observation of the investigated skin parameters did not show superior effects of the addition of hyaluronic acid (HA) to collagen. Therefore, the ability of supplementation with HA to improve the effects on investigated skin parameters beyond the supplementation of collagen alone cannot be confirmed.

Treatment of menopausal skin - A narrative review of existing treatments, controversies, and future perspectives

Menopause is a state of estrogen deficiency that affects numerous estrogen-dependent tissues in the female body. Skin is one of the most affected organs. Many consider menopausal skin changes to be merely an aesthetic problem; however, they can significantly affect women's quality of life. Currently, there are no approved effective treatments to prevent or alleviate skin changes associated with estrogen deficiency. Standard systemic hormone replacement therapy used to treat menopausal symptoms may be effective to some degree for skin treatment. In addition, compounded bioidentical hormone replacement therapy, selective estrogen receptor modulators, and phytoestrogens could also be used for skin treatment, although this is only hypothetical due to lack of data. Many questions therefore remain unanswered. On the other hand, topical, low-dose estrogen that would act only on the skin without systemic effects could be a possible option, as could be skin-only acting topical phytoestrogens. Such topical products without systemic effects could play a role in the treatment of menopausal skin. However, they are not currently approved because there is insufficient data on their safety and efficacy. A healthy lifestyle could have a positive effect on the menopausal skin. In this review, we provide an overview of the characteristics of menopausal skin, an outlook on the future treatment of menopausal skin with estrogens and other approaches, and the associated controversies and speculations. Overall, the importance of menopausal skin changes should not be neglected, and high-quality research is needed to gain new insights into the treatment of menopausal skin.

A view on the skin-bone axis: unraveling similarities and potential of crosstalk

The phrase "skin as a mirror of internal medicine," which means that the skin reflects many of the diseases of the internal organs, is a well-known notion. Despite the phenotypic differences between the soft skin and hard bone, the skin and bone are highly associated. Skin and bone consist of fibroblasts and osteoblasts, respectively, which secrete collagen and are involved in synthesis, while Langerhans cells and osteoclasts control turnover. Moreover, the quality and quantity of collagen in the skin and bone may be modified by aging, inflammation, estrogen, diabetes, and glucocorticoids. Skin and bone collagen are pathologically modified by aging, drugs, and metabolic diseases, such as diabetes. The structural similarities between the skin and bone and the crosstalk controlling their mutual pathological effects have led to the advocacy of the skin-bone axis. Thus, the skin may mirror the health of the bones and conversely, the condition of the skin may be reflected in the bones. From the perspective of the skin-bone axis, the similarities between skin and bone anatomy, function, and pathology, as well as the crosstalk between the two, are discussed in this review. A thorough elucidation of the pathways governing the skin-bone axis crosstalk would enhance our understanding of disease pathophysiology, facilitating the development of new diagnostics and therapies for skin collagen-induced bone disease and of new osteoporosis diagnostics and therapies that enhance skin collagen to increase bone quality and density.

Skin Rejuvenation in Women using Menopausal Hormone Therapy: A Systematic Review and Meta-Analysis

OBJECTIVES

To evaluate the effect of menopausal hormone therapy (MHT) on skin aging in menopausal women.

METHODS

Studies were identified by searching PubMed, Cochrane Library, Google Scholar, and ClinicalTrials.gov databases using the key words "hormone replacement therapy" AND "skin" AND "menopausal." Studies that used and compared oral/transdermal MHT with placebo or another type of treatment in menopausal women aged 45-55 years were selected.

RESULTS

From 1,526 studies identified, 15 studies comprising 1,589 patients were included in the final analysis. Our meta-analysis aimed to compare skin elasticity (standard [Std] mean difference = 0.28; 95% confidence interval [CI], 0.03-0.54; P = 0.03), skin thickness (Std. mean difference = 1.27; 95% CI, 0.88-1.66; P < 0.00001), collagen content (Std. mean difference = 2.01; 95% CI, 1.42-2.61; P < 0.00001), and skin dryness (Std. mean difference = 0.15; 95% CI, -0.05 to 0.35; P = 0.14).

CONCLUSIONS

MHT increases elasticity and collagen content in the skin, thereby reducing the severity of wrinkles and increasing skin thickness. Nevertheless, more well-conducted clinical trials are required to answer all questions in an evidence-based manner.

Effects of Oral Collagen for Skin Anti-Aging: A Systematic Review and Meta-Analysis

This paper presents a systematic review and meta-analysis of 26 randomized controlled trials (RCTs) involving 1721 patients to assess the effects of hydrolyzed collagen (HC) supplementation on skin hydration and elasticity. The results showed that HC supplementation significantly improved skin hydration (test for overall effect: Z = 4.94, p < 0.00001) and elasticity (test for overall effect: Z = 4.49, p < 0.00001) compared to the placebo group. Subgroup analyses demonstrated that the effects of HC supplementation on skin hydration varied based on the source of collagen and the duration of supplementation. However, there were no significant differences in the effects of different sources (p = 0.21) of collagen or corresponding measurements (p = 0.06) on skin elasticity. The study also identified several biases in the included RCTs. Overall, the findings suggest that HC supplementation can have positive effects on skin health, but further large-scale randomized control trials are necessary to confirm these findings.

Assessing vaginal wall thickness by transvaginal ultrasound in breast cancer survivors: A pilot study

AIM

There is need for a straightforward objective measure to evaluate vaginal wall changes related to hypoestrogenism. The aim of this pilot study was to evaluate a transvaginal ultrasound procedure for the quantification of vaginal wall thickness in order to differentiate between healthy premenopausal women and postmenopausal women with genitourinary syndrome of menopause using ultra-low-level estrogen status as a model.

METHODS

We performed a prospective, two-arm, cross-sectional pilot study comparing vaginal wall thickness measured by transvaginal ultrasound in postmenopausal breast cancer survivors using aromatase inhibitors with genitourinary syndrome of menopause (GSM group) and healthy premenopausal women (control or C group) from October 2020 to March 2022. After intravaginal introduction of 20 cm³ of sonographic gel, vaginal wall thickness was measured by transvaginal ultrasound in the anterior, posterior, and right and left lateral walls (four quadrants). The study methods followed the STROBE checklist.

RESULTS

According to the results of a two-sided t-test, the mean vaginal wall thickness of the four quadrants in the GSM group was significantly less than that of the C group (2.25 mm vs 4.17 mm, respectively; p < 0.001). Likewise, the thickness of each of the vaginal walls (anterior, posterior, right and left lateral) statistically differed between the two groups (p < 0.001).

CONCLUSION

Transvaginal ultrasound with intravaginal gel may be a feasible objective technique to assess genitourinary syndrome of menopause, showing clear differences in vaginal wall thickness between breast cancer survivors using aromatase inhibitors and premenopausal women. Possible correlations with symptoms or treatment response should be assessed in future studies.

Multidirectional activity of bakuchiol against cellular mechanisms of facial aging - Experimental evidence for a holistic treatment approach

Objective

Skin ageing is a multifactorial process involving formation of reactive oxygen species, consecutive inflammation with reduced epidermal and dermal cell viability and resulting damage to the extracellular matrix. Effective dermocosmetic treatment modalities should ideally address these hallmarks in a holistic approach. Here, we determined the corresponding activity profile of bakuchiol, a plant‐derived meroterpene, in an array of in vitro, ex vivo and in vivo studies and compared it to retinol, currently considered as gold standard in topical antiageing cosmetics.

Methods

The antioxidative capacity and power of bakuchiol and retinol were analysed by measuring 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH) reduction via its absorption decay and electron spin resonance spectroscopy, respectively. Effects on prostaglandin E2 (PGE2), macrophage migration inhibitory factor (MIF), fibroblast growth factor 7 (FGF7), collagen type I and VII (COL1A1, COL7A1), fibronectin (FN) levels as well as the metabolization of water‐soluble tetrazolium 1 (WST‐1) were determined in human dermal fibroblasts. Epidermal regeneration was assessed utilizing an in vitro wound healing model. FN protein levels were analysed ex vivo after treatment with a formulation containing bakuchiol, retinol or vehicle using suction blister fluid. Skin condition improvement was determined in vivo in a split‐face comparison study after application of bakuchiol or vehicle.

Results

In contrast to retinol, bakuchiol demonstrated high antioxidative efficacy. Levels of PGE2 and MIF were significantly decreased by both bakuchiol and retinol. Bakuchiol but not retinol significantly increased FGF7 protein levels. WST‐1 metabolization levels were significantly augmented by bakuchiol and retinol. Bakuchiol and retinol application led to a significant augmentation of COL1A1, COL7A1 and FN protein levels. Wounds supplemented with bakuchiol but not retinol displayed a significant increase in epidermis regeneration. Clinically, areas treated with a bakuchiol‐containing formulation showed a statistically significant increase in FN protein values after a 4‐week application compared to untreated areas and areas treated with vehicle.

Conclusion

These data provide evidence for the multidirectional efficacy of bakuchiol against cellular hallmarks of skin ageing. Its activity profile shares some common features with retinol but demonstrates several hitherto unknown biopositive effects in our studies, namely stimulation of the critical extracellular matrix component FN, and accelerated epidermal regeneration and wound healing.

Beneficial Effects of Young Coconut Juice on Increasing Skin Thickness, Enhancing Skin Whitening, and Reducing Skin Wrinkles in Ovariectomized Rats

It has been previously demonstrated in light microscopic and immunohistochemical studies that ovariectomized rats receiving young coconut juice at 100 mL/kg BW showed much better wound healing and improved skin complexion. Nevertheless, it was found that young coconut juice at 100 mL/kg BW/day caused unfavorable side effects, such as glycogen deposition in the liver. Therefore, in the current study, 3 lower doses (10, 20, and 40 mL/kg BW/day) were optimized, and the ultrastructure was further investigated. Compared to normal rats, all the parameters regarding skin changes, including epidermal and dermal thickness, the number of hair follicles, the diameters of collagen fibrils, perimeters, and nuclei of fibroblast and keratinocyte cells, and ultrastructural changes in keratinocyte and fibroblast cells were significantly reduced in ovariectomized rats. Those parameters in the ovariectomized rats were restored to normal by injecting estradiol benzoate or by feeding young coconut juice to the rats, where the effect was found to be dose-related but not in the case of all the parameters. In most cases, a dose of young coconut juiceof 40 mL/kg BW/day was the optimal dose. The results suggest that young coconut juice may be as effective as estradiol benzoate in reducing skin atrophy/aging, probably as a selective estrogen receptor moderator.

Difference of body surface temperature in stable chronic obstructive pulmonary disease patients with different degree of airflow limitation

BACKGROUND

This study aimed to investigate the changes of body surface temperature of stable chronic obstructive pulmonary disease (COPD) patients and explore its clinical significance for the progression of COPD.

OBJECTIVES

The aim of this study was to explore the correlation between body surface temperature and disease severity in COPD patients.

METHODS

From May 2015 to May 2016, the patients who were diagnosed as COPD at stable phase (n = 148) were enrolled in this study. The subjects in control group (n = 49) were healthy people. The patients' general condition modified Medical Research Council (mMRC) dyspnea scale and the COPD assessment test (CAT) score were recorded, and pulmonary function of patients was determined. Back average temperature measurement was made using a thermal infrared imager (DT-9875, CEM, China).

RESULTS

Patients in the COPD group had significantly lower mean temperatures of the back than those in the control group. The mean temperature of the back presented a decreased tendency with the aggravation of airflow limitation. Correlation analysis revealed that in the COPD group, the back temperature was negatively correlated with smoking index and mMRC score. FEV1%, FVC% and FEV1/FVC were positively correlated with pulmonary function. Smoking showed a tendency to lower the back temperature of COPD patients.

CONCLUSIONS

This study preliminarily suggested that the body surface temperature of COPD patients decreased compared with that of healthy people, which may be associated with the dysfunction of autonomic nerve, increased basal metabolic rate, metabolic syndrome and peripheral nerve injury in COPD patients.

A role for estrogen in skin ageing and dermal biomechanics

The skin is the body's primary defence against the external environment, preventing infection and desiccation. Therefore, alterations to skin homeostasis, for example with skin ageing, increase susceptibility to skin disease and injury. Skin biological ageing is uniquely influenced by a combination of intrinsic and extrinsic (primarily photoageing) factors, with differential effects on skin structure and function. Interestingly, skin architecture rapidly changes following the menopause, as a direct result of reduced circulating 17β-estradiol. The traditional clinical benefit of estrogens are supported by recent experimental data, where 17β-estradiol supplementation prevents age-related decline in the skin's structural and mechanical properties. However, the off-target effects of 17β-estradiol continue to challenge therapeutic application. Here we discuss how ageing alters the physiological and structural properties of the dermal extracellular matrix, and explore how estrogen receptor-targeted therapies may restore the mechanical defects associated with skin ageing.

Elucidating the cellular mechanism for E2-induced dermal fibrosis

BACKGROUND

Both TGFβ and estradiol (E2), a form of estrogen, are pro-fibrotic in the skin. In the connective tissue disease, systemic sclerosis (SSc), both TGFβ and E2 are likely pathogenic. Yet the regulation of TGFβ in E2-induced dermal fibrosis remains ill-defined. Elucidating those regulatory mechanisms will improve the understanding of fibrotic disease pathogenesis and set the stage for developing potential therapeutics. Using E2-stimulated primary human dermal fibroblasts in vitro and human skin tissue ex vivo, we identified the important regulatory proteins for TGFβ and investigated the extracellular matrix (ECM) components that are directly stimulated by E2-induced TGFβ signaling.

METHODS

We used primary human dermal fibroblasts in vitro and human skin tissue ex vivo stimulated with E2 or vehicle (ethanol) to measure TGFβ1 and TGFβ2 levels using quantitative PCR (qPCR). To identify the necessary cell signaling proteins in E2-induced TGFβ1 and TGFβ2 transcription, human dermal fibroblasts were pre-treated with an inhibitor of the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathway, U0126. Finally, human skin tissue ex vivo was pre-treated with SB-431542, a TGFβ receptor inhibitor, and ICI 182,780, an estrogen receptor α (ERα) inhibitor, to establish the effects of TGFβ and ERα signaling on E2-induced collagen 22A1 (Col22A1) transcription.

RESULTS

We found that expression of TGFβ1, TGFβ2, and Col22A1, a TGFβ-responsive gene, is induced in response to E2 stimulation. Mechanistically, Col22A1 induction was blocked by SB-431542 and ICI 182,780 despite E2 stimulation. Additionally, inhibiting E2-induced ERK/MAPK activation and early growth response 1 (EGR1) transcription prevents the E2-induced increase in TGFβ1 and TGFβ2 transcription and translation.

CONCLUSIONS

We conclude that E2-induced dermal fibrosis occurs in part through induction of TGFβ1, 2, and Col22A1, which is regulated through EGR1 and the MAPK pathway. Thus, blocking estrogen signaling and/or production may be a novel therapeutic option in pro-fibrotic diseases.

Skin Biomechanics and miRNA Expression Following Chronic UVB Irradiation

Objective: Exposure to ultraviolet (UV) light from the sun is known to accelerate the skin aging process and leads to significant alterations in skin biomechanics; however, the molecular mechanisms by which chronic UVB affects biomechanical properties of the skin have not been well described. Approach: A murine model for chronic UVB exposure was used to examine changes in epidermal barrier function, skin biomechanics, and miRNA expression as a result of UVB. Results: UVB irradiation caused skin to be weaker, less elastic, stiffer, and less pliable. Notably, these changes were not reversed after a 5-week period of recovery. Following UVB exposure, dermal collagen fibrils were significantly smaller in diameter and expression of the miR-34 family was significantly increased. Innovation: To our knowledge, this is the first study to concurrently examine alterations in skin function, miRNA expression, and tissue biomechanics in response to chronic UVB exposure. Conclusion: The data suggest that UVB alters miR-34 family expression in skin, in addition to dysregulating collagen structure with subsequent reductions in strength and elasticity. miRNAs may play a pivotal role in regulating extracellular matrix deposition and skin biomechanics following chronic UVB exposure, and thus may be a possible target for therapeutic development. However, additional studies are needed to directly probe the link between UVB exposure, miRNA production, and skin biomechanics.

Skin Ageing: Pathophysiology and Current Market Treatment Approaches

Ageing is a natural phenomenon which is a fold, ridge and crease in the skin that occurs due to loss of body mass, poor hydration, disintegration of dermis and epidermis junction. The Skin ageing process involves many changes that occur due to the combination of both endogenous factors (gene mutation, cellular metabolism, and hormonal factor) and exogenous factors (U.V, pollutants, chemical, and toxins). In 1950, the number of older people were found to be almost 205 million across the globe. But this number almost got 4 times by the year 2012 and the number of older persons increased to a massive amount of 810 million. The ageing of the skin occurs due to various mechanisms like glycation, free radical, cell cycle, and cellular and molecular mechanism of skin ageing. In this review article, we have discussed the treatment, worldwide newer therapies and marketed formulation that are currently available for the reduction of skin ageing. The most promising and revolutionizing field of nanotechnology is mostly applied in the field of dermatology, cosmetics, and biomedical applications. Nanotechnology also plays a vital role in increasing the efficacy of the product.

Topical estradiol increases epidermal thickness and dermal collagen of foreskin prior to hypospadia surgery - Randomized double blinded controlled trial

INTRODUCTION

The use of preoperative topical testosterone stimulation prior to hypospadias correction aims to increase penile size and achieve better surgical results. Topical estradiol has been shown to improve the quality of skin in other sites, but its use in boys with hypospadia has not yet been elucidated.

OBJECTIVE

This study aims to evaluate the primary effects in epidermal thickness and collagen distribution of estradiol compared to testosterone and placebo in skin of prepuce before hypospadia surgery.

MATHERIALS AND METHODS

Patients were randomized into three groups according to the topical hormone used: TG: Testosterone ointment; EG: Estradiol ointment; CG: Neutral base ointment. Fragments of foreskin were excised, fixed and then sectioned for histology. For each sample, epidermal thickness and dermal collagen expression was measured by specific computer analysis, P-values of <0.05.

RESULTS

Thirty-three patients with a mean age of 4.01 ± 2.92 years were included. Hypospadia classification was similar in all three groups. Mean epidermal thickness and collagen type I expression in EG were greater than those of the other groups. Collagen type III expression was similar in all groups.

DISCUSSION

Foreskin has a fundamental role in many techniques of hypospadias surgery and can be used either as a graft or a flap in the correction of the penile defect. Increase of epidermal thickness and dermal collagen observed in the present study has already been related to use of estradiol in other skin sites, but not yet in foreskin. Further studies are needed to evaluate the real significance of these findings in boys with hypospadias.

CONCLUSION

Use of topical estradiol before hypospadias surgery lead to greater epidermal thickness and increases dermal collagen expression in foreskin.

Anti-aging and Sunscreens: Paradigm Shift in Cosmetics

Skin, being one of the vital organs and a protective barrier needs to be pampered and taken care of from early childhood. It is the most visible and the widest exposed organ and by far reflects the general health condition and the aging process in humans. Both intrinsic and extrinsic factors contribute to this complex biological process of skin aging. In recent times, skin health and its beauty is perceived as an indicator of one’s health which has resulted in an increasing demand for anti-aging products. Exposure to UV radiation is considered to be one of the factors responsible for aging termed as photoaging. In this review, we have discussed the various factors which may accelerate the process of skin aging. Various approaches and strategies to delay the process of skin aging have been emphasized upon. The patents filed in the area of anti-aging and sunscreen products have also been reviewed to gain an insight into the new formulations which have been developed as an anti-aging product. There has been a tremendous rise in the cosmetic and cosmeceuticals market with products having a dual activity of anti-aging and sun protection. Research is constantly on the rise to ensure the safety of these products. Alternatives to the current topical application of sunscreen are being considered to overcome the drawback of reapplication of the sunscreen often which can be a boon to the cosmeceutical market.

Estradiol levels are elevated in older men with diffuse cutaneous SSc and are associated with decreased survival

BACKGROUND

Systemic sclerosis (SSc) is a female-predominant disease, characterized by excessive extracellular matrix deposition (ECM) with dermal and internal organ fibrosis. Considering the sex-based disparity in disease incidence, estradiol (E2), an estrogen form with pro-fibrotic effects, may play a role in SSc. We reported that post-menopausal women with diffuse cutaneous (dc)SSc have higher serum E2 levels compared to similar aged, healthy controls. Since males with SSc tend to have more severe disease, we examined serum E2 in dcSSc males in relation to disease characteristics and survival.

METHODS

We measured serum E2 in 83 dcSSc men > 50 years old from the University of Pittsburgh Scleroderma Center and similar aged healthy controls. Using statistical modeling, we examined the associations between serum E2, internal organ involvement, autoantibody profiles, and survival.

RESULTS

Male dcSSc patients had significantly higher serum E2 levels compared to healthy males and similar aged dcSSc post-menopausal women. Male dcSSc patients with high serum E2 had significantly more heart involvement, a trend for higher skin thickness progression rate, and worse survival. Using Cox regression modeling, increased serum E2 levels in anti-Scl-70 antibody-positive dcSSc males were associated with an increased risk of death.

CONCLUSIONS

dcSSc males > 50 years old have higher levels of serum E2 compared to healthy controls and dcSSc post-menopausal women. Elevated serum E2 levels in dcSSc males are associated with heart involvement, trend to progression of dermal fibrosis, and, if anti-Scl-70 antibody positive, worse survival. Our study expands on previous work implicating E2 in dermal fibrosis in SSc and associates E2 levels with internal organ involvement and survival. These data suggest a role for estrogen imbalance in dcSSc.

Estrogen-deficient skin: The role of topical therapy

Menopause is a major turning point in a woman's life that is characterized by declining ovarian function and decreased serum estrogen levels. The resulting hormonal changes particularly affect the skin, with postmenopausal symptoms such as loss of structural architecture and increased propensity to damage becoming rapidly noticeable. Interestingly, studies have shown that estrogen deprivation in postmenopausal conditions accelerates many skin changes, including dryness, atrophy, fine wrinkling, and poor wound healing. Thus, the effects of low estrogen on the skin are an important endogenous cause of aging skin in women, yet topical treatment strategies that target cutaneous symptoms are limited. The goal of this article is to provide an overview of the role of estrogen in the skin and changes associated with estrogen deficiency, as well as review alternatives to systemic estrogen therapy and describe the effects of these interventions on cutaneous aging in postmenopausal skin. Specifically, clinical studies that utilize topical estrogens and topical isoflavones, which are soy-derived compounds that interact with estrogen receptors, are discussed.

Correlation between skin and bone parameters in women with postmenopausal osteoporosis: A systematic review

Skin and bone share similarities in terms of biochemical composition.Some authors have hypothesized that their properties could evolve concomitantly with age, allowing the estimation of the parameters of one from those of the other.We performed a systematic review of studies reporting the correlation between skin and bone parameters in women with postmenopausal osteoporosis.Fourteen studies - including 1974 patients - were included in the review.Three of these studies included two groups of participants - osteoporotic and non-osteoporotic - in order to compare skin parameters between them: two studies found a significant difference between the two groups and one did not.Eleven of these studies included one population of interest and compared its skin and bone parameters in a continuous manner: eight studies compared dermal thickness to bone mineral density (seven found a significant correlation [R = 0.19-0.486] and one did not); two studies compared skin elasticity to bone mineral density (both found a significant correlation [R = 0.44-0.57); and one study compared skin collagen to bone mineral density and found a significant correlation (R = 0.587).It can be assumed that the estimation of skin alterations from ageing could help in estimating concomitant bone alterations. Cite this article: EFORT Open Rev 2018;3:449-460. DOI: 10.1302/2058-5241.3.160088.

Chronic UVB-irradiation actuates perpetuated dermal matrix remodeling in female mice: Protective role of estrogen

Chronic UVB-exposure and declined estradiol production after menopause represent important factors leading to extrinsic and intrinsic aging, respectively. Remodeling of the extracellular matrix (ECM) plays a crucial role in both responses. Whether the dermal ECM is able to recover after cessation of UVB-irradiation in dependence of estradiol is not known, however of relevance when regarding possible treatment options. Therefore, the endogenous sex hormone production was depleted by ovariectomy in female mice. Half of the mice received estradiol substitution. Mice were UVB-irradiated for 20 weeks and afterwards kept for 10 weeks without irradiation. The collagen-, hyaluronan- and proteoglycan- (versican, biglycan, lumican) matrix, collagen cleavage products and functional skin parameters were analyzed. The intrinsic aging process was characterized by increased collagen fragmentation and accumulation of biglycan. Chronic UVB-irradiation additionally augmented the lumican, versican and hyaluronan content of the dermis. In the absence of further UVB-irradiation the degradation of collagen and accumulation of biglycan in the extrinsically aged group was perpetuated in an excessive matter. Whereas estradiol increased the proteoglycan content, it reversed the effects of the perpetuated extrinsic response on collagen degradation. Suspension of the intrinsic pathway might therefore be sufficient to antagonize UVB-evoked long-term damage to the dermal ECM.

The effect of oral collagen peptide supplementation on skin moisture and the dermal collagen network: evidence from an ex vivo model and randomized, placebo-controlled clinical trials

BACKGROUND

Skin dryness and an accelerated fragmentation of the collagen network in the dermis are hallmarks of skin aging. Nutrition is a key factor influencing skin health and consequently its appearance. A wide range of dietary supplements is offered to improve skin health. Collagen peptides are used as a bioactive ingredient in nutricosmetic products and have been shown in preclinical studies to improve skin barrier function, to induce the synthesis of collagen and hyaluronic acid, and to promote fibroblast growth and migration. Our aim was to investigate the effect of oral supplementation with specific collagen peptides on skin hydration and the dermal collagen network in a clinical setting.

METHODS

Two placebo-controlled clinical trials were run to assess the effect of a daily oral supplementation with collagen peptides on skin hydration by corneometry, on collagen density by high-resolution ultrasound and on collagen fragmentation by reflectance confocal microscopy. Human skin explants were used to study extracellular matrix components in the presence of collagen peptides ex vivo.

RESULTS

Oral collagen peptide supplementation significantly increased skin hydration after 8 weeks of intake. The collagen density in the dermis significantly increased and the fragmentation of the dermal collagen network significantly decreased already after 4 weeks of supplementation. Both effects persisted after 12 weeks. Ex vivo experiments demonstrated that collagen peptides induce collagen as well as glycosaminoglycan production, offering a mechanistic explanation for the observed clinical effects.

CONCLUSION

The oral supplementation with collagen peptides is efficacious to improve hallmarks of skin aging.

A pilot study of the impacts of menopause on the anogenital distance

Objectives

It has been known that there is a difference in anogenital distance (AGD) in the animals and newborn depending on the exposure of androgenic hormones. The anatomical changes occur in the female genitalia in women after menopause. This was pilot study to find out whether the menopause affects AGD.

Methods

We evaluated a total of 50 women targeted for premenopausal and postmenopausal group in each 25 people. AGD was defined as a length between the posterior commissure of labia and anal center. AGD was measured in lithotomy position using sterile paper ruler. In order to control bias of the height and weight, which could influence the AGD, anogenital index (AGI) is defined as the weight divided by the AGD value. We used a Mann-Whitney U test to analyze the relationship between AGD and menopause for statistical analysis.

Results

AGD was significantly longer in premenopausal women compared to postmenopausal women (34.8 ± 6.4 vs. 30.3 ± 6.6, P = 0.019). AGI was significantly higher in premenopausal women than postmenopausal women (1.7 ± 0.4 vs. 1.3 ± 0.3, P ≤ 0.000).

Conclusion

The changes of AGD and AGI in postmenopausal women demonstrated to have potential to be used as on scale predicting the physical changes that may occur after menopause. This study could be used as the cornerstone of a large-scale studies in the future.

Efficacy of porcine placental extract on wrinkle widths below the eye in climacteric women

OBJECTIVE

Injections of human placental extract, which is known to play a role in skin regulation, have long been used for the treatment of skin wrinkles and non-healing wounds. Porcine placental extract (PPE), an oral supplement, was recently developed for this purpose. The aim of this study was to assess whether PPE has a positive effect on the improvement of fine wrinkles below the eye in climacteric women.

METHODS

We first non-invasively measured wrinkle widths with a skin analyzer in a cross-section of 185 healthy adult Japanese women. Next, 44 climacteric women with mild or few climacteric symptoms were enrolled into an open-label, randomized, controlled study of the effect of PPE on wrinkle widths. A retrospective comparison of wrinkle widths in 123 climacteric women with climacteric symptoms with or without PPE treatment was also performed.

RESULTS

Wrinkle widths below the eye in women ≥ 30 years of age were significantly higher than in women 20-29 years of age. Treatment with three capsules of PPE per day was significantly (p < 0.05) effective in reducing wrinkle widths at 24 weeks compared with control subjects. Retrospective analysis showed that subjects treated with three (p < 0.05) and six (p < 0.01) capsules of PPE per day observed a significant reduction in wrinkle widths compared with untreated subjects.

CONCLUSION

Oral PPE treatment is a possible option for improving the appearance of fine wrinkles below the eye in climacteric women.

Development of an in vitro model of menopause using primary human dermal fibroblasts

OBJECTIVE

To overcome the current lack of in vitro models to specifically reproduce hormonal skin ageing in women, and in search of active ingredients with innovative efficacy claim for cosmetic skin care, we developed a cell culture-based model by simulating menopause's hormonal decline and assessed several parameters of collagen metabolism.

METHODS

Human dermal fibroblasts were incubated with media containing 17β-oestradiol, progesterone, dehydroepiandrosterone, growth hormone and insulin-like growth factor-1 at concentrations corresponding to those of non-menopausal women's sera and then of menopausal women's sera. We measured cell proliferation [by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT)], matrix metalloproteinase-1 and metalloproteinase-3 (MMPs) release (by enzyme-linked immunosorbent assay - ELISA), total collagen deposition (by Sirius red staining), types I and III collagen deposition (by ELISA), and types I and III procollagen gene expression (by real-time q-RT-PCR).

RESULTS

Our results showed a significant decrease over time in cell proliferation, collagen deposition and type III/type I collagen ratio, together with an increase in MMP release, when cells were incubated in media containing sex hormones at menopausal levels. This is consistent with in vivo data from menopausal women available in the literature. Surprisingly, procollagen gene expression was only reduced within the first hours and increased afterwards when compared with non-menopausal culture conditions.

CONCLUSION

Our results demonstrated that the increased procollagen synthesis with menopausal conditions was not sufficient to compensate for the MMPs' catabolic effects and/or the impaired procollagen protein maturation, resulting in a decrease in extracellular collagen content. These findings add to the overall understanding of hormone-dependent skin behaviour and highlight the suitability of this in vitro model for cosmetic actives testing aiming to underpin claims of anti-ageing efficacy, specifically for menopausal women, regarding collagen metabolism and balance of types, for maintenance of dermal mechanical properties.

Ultrasonographic assessment of skin thickness in patients with PCOS - a case-control study

OBJECTIVE

To measure skin thickness in patients with polycystic ovary syndrome (PCOS) in comparison to controls and to examine a possible association with sex steroids, body mass index, lipid profile and hyperinsulinemia.

METHODS

Thirty patients with confirmed PCOS were compared to thirty-two women presenting for infertility workup. Skin thickness was measured using high-resolution ultrasound in a standardized area, blood samples were collected once at presentation.

RESULTS

Patients with PCOS showed a statistically significant thicker skin than women in the control group (0.95 mm (±0.093 mm) versus 0.85 mm (±0.077 mm, p < 0.0001)). LH, estradiol, testosterone, the free androgen index, triglycerides, cholesterol, LDL-cholesterol and body mass index were significantly increased in PCOS - patients. No correlation between hyperinsulinemia and skin thickness was seen.

CONCLUSIONS

PCOS - patients showed a greater skin thickness in comparison to women without PCOS. This might be due to proliferative effects of sex steroids such as estrogens and testosterone and metabolic derangements on skin thickness.

Estradiol promotes the development of a fibrotic phenotype and is increased in the serum of patients with systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is more prevalent in women. Our goal is to determine the effects of 17β-estradiol (E2) on the development of fibrosis and to compare circulating levels of estrogens in SSc patients and healthy controls.

METHODS

Using primary human dermal fibroblasts, we evaluated the effect of E2 on fibronectin (FN) expression with and without the estrogen receptor (ER) antagonist ICI 182,780, inhibitors of signaling, propyl-pyrazole-triol, an ERα specific ligand, and genistein, an ERβ selective ligand, to identify the signaling pathways mediating E2's effect. We confirmed the fibrotic effect of E2 in human skin using an ex vivo organ culture model. Lastly, we measured levels of E2 and estrone in serum samples from SSc patients with diffuse cutaneous involvement and healthy controls using mass spectrometry.

RESULTS

E2 increased expression of FN in dermal fibroblasts. ICI 182,780, inositol-1,4,5-triphosphate inhibitor, and p38 mitogen-activated protein kinase inhibitor blocked the effects of E2 on FN. Propyl-pyrazole-triol, but not genistein, significantly increased FN expression. Ex vivo, E2 induced fibrosis of human skin. The effects of E2 were abrogated by ICI 182,780. Circulating levels of E2 and estrone were significantly increased in sera of patients with diffuse cutaneous SSc.

CONCLUSION

Our findings implicate estrogens in the fibrotic process and may explain the preponderance of SSc in women. ICI 182,780 or other ER signaling antagonists may be effective agents for the treatment of fibrosis.

17β-estradiol protects human skin fibroblasts and keratinocytes against oxidative damage

BACKGROUND

Reactive oxygen species (ROS) cause severe damage to extracellular matrix and to molecular structure of DNA, proteins and lipids. Accumulation of these molecular changes apparently constitutes the basis of cell ageing. 17b-estradiol (E2) has a key role in skin ageing homeostasis as evidenced by the accelerated decline in skin appearance seen in the perimenopausal years. Oestrogens improve many aspects of the skin such as skin thickness, vascularization, collagen content and quality. Despite these clinical evidences, the effects of oestrogens on skin at the cellular level need further clarification.

MATERIALS AND METHODS

HaCaT and human fibroblasts were cultured under various conditions with E2 and H2 O2 ; then were subjected to immunofluorescence and western blot analysis. Lipoperoxidation was investigated using BODIPY.

RESULTS

In human fibroblasts oxidative stress decreases procollagen-I synthesis, while E2 significantly increases it. Fibroblasts and HaCaT cells viability in the presence of E2 demonstrates a notably increased resistance to H2 O2 effects. Furthermore E2 is able to counteract H2 O2 -mediated lipoperoxidation and DNA oxidative damage in skin cells.

DISCUSSION

In this study we highlight that the menopause-associated oestrogens decline is involved in reduced collagen production and that E2 could counteract the detrimental effects of oxidative stress on the dermal compartment during skin aging. Furthermore, our data show that physiological concentrations of oestrogens are able to interfere with ROS-mediated cell viability reduction and to protect human skin cells against oxidative damage to cellular membranes and nucleic acids structure.

CONCLUSION

Our experimental data show that the presence of 17β-estradiol may protect skin cells against oxidative damage and that the dramatic lowering of oestrogen levels during menopause, could render skin more susceptible to oxidative damage.

Estradiol protects dermal hyaluronan/versican matrix during photoaging by release of epidermal growth factor from keratinocytes

Hyaluronan (HA) and versican are key components of the dermis and are responsive to ultraviolet (UV)B-induced remodeling. The aim of this study was to explore the molecular mechanisms mediating the effects of estrogen (E(2)) on HA-rich extracellular matrix during photoaging. Hairless skh-1 mice were irradiated with UVB (three times, 1 minimal erythema dose (80 mJ/cm(2)), weekly) for 10 weeks, and endogenous sex hormone production was abrogated by ovariectomy. Subcutaneous substitution of E(2) by means of controlled-release pellets caused a strong increase in the dermal HA content in both irradiated and nonirradiated skin. The increase in dermal HA correlated with induction of HA synthase HAS3 by E(2). Expression of splice variant 2 of the HA-binding proteoglycan versican was also increased by E(2). In search of candidate mediators of these effects, it was found that E(2) strongly induced the expression of epidermal growth factor (EGF) in UVB-irradiated epidermis in vivo and in keratinocytes in vitro. EGF in turn up-regulated the expression of HAS3 and versican V2 in dermal fibroblasts. HAS3 knockdown by shRNA caused inhibition of fibroblast proliferation. Furthermore, HAS3 and versican V2 induction by E(2) correlated positively with proliferation in vivo. In addition, the accumulation of inflammatory macrophages, expression of inducible cyclooxygenase 2, as well as proinflammatory monocyte chemotactic protein 1 were decreased in response to E(2) in the dermis. Collectively, these data suggest that E(2) treatment increases the amount of dermal HA and versican V2 via paracrine release of EGF, which may be implicated in the pro-proliferative and anti-inflammatory effects of E(2) during photoaging.

The effect of menopause on the skin and other connective tissues

Cutaneous ageing manifests itself as a progressive reduction in function and reserve capacity of skin tissue. Collagen atrophy is a major factor in skin ageing. There is a strong correlation between skin collagen loss and oestrogen deficiency due to the menopause. Skin ageing is associated with a progressive increase in extensibility and a reduction in elasticity. With increasing age, the skin also becomes more fragile and susceptible to trauma, leading to more lacerations and bruising. Furthermore, wound healing is impaired in older women. Oestrogen use after the menopause increases collagen content, dermal thickness and elasticity, and it decreases the likelihood of senile dry skin. Large-scale clinical trials are necessary to help make informed recommendations regarding postmenopausal oestrogen use and its role in the prevention of skin ageing. Oestrogen has profound effects on connective tissue turnover, no matter the site. It has been shown that menopause has similar effects on the connective tissue of the carotid artery media, intervertebral discs and bones.

Innovative cosmeceuticals: sirtuin activators and anti-glycation compounds

Skin aging is a combination of natural aging with superimposed photoaging. Naturally aged skin is thin, fragile and finely wrinkled whereas photoaged skin is rough and thickened with deep coarse wrinkles. In addition photoaging is characterized by mottled pigmentation, solar lentigines, telangectasias and a loss of elasticity. The science behind skin aging has exploded in the past decade. Skin aging has now been defined on both a cellular and molecular level. The study of genomics in aging skin provides us with potential targets as points for intervention. In this regard, the science behind skin aging becomes a platform for the development of new anti-aging strategies and products. In this paper two new and emerging approaches to treat aging skin will be discussed. Sirtuin activating and anti-glycation products are already being marketed by cosmetic and pharmaceutical companies. These anti-aging approaches are backed by basic science research and the ingredients used are supported by proof of concept studies although clinical trials are often lacking. It is this bench to beauty counter approach to cosmeceuticals that remains an industry standard today.

Estrogen and skin: therapeutic options

Aging of the skin is associated with skin thinning, atrophy, dryness, wrinkling, and delayed wound healing. These undesirable aging effects are exacerbated by declining estrogen levels in postmenopausal women. With the rise in interest in long-term postmenopausal skin management, studies on the restorative benefits that estrogen may have on aged skin have expanded. Systemic estrogen replacement therapy (ERT) has been shown to improve some aspects of skin. Estrogen restores skin thickness by increasing collagen synthesis while limiting excessive collagen degradation. Wrinkling is improved following estrogen treatment since estrogen enhances the morphology and synthesis of elastic fibers, collagen type III, and hyaluronic acids. Dryness is also alleviated through increased water-holding capacity, increased sebum production, and improved barrier function of the skin. Furthermore, estrogen modulates local inflammation, granulation, re-epithelialization, and possibly wound contraction, which collectively accelerates wound healing at the expense of forming lower quality scars. Despite its promises, long-term ERT has been associated with harmful systemic effects. In the search for safe and effective alternatives with more focused effects on the skin, topical estrogens, phytoestrogens, and tissue-specific drugs called selective estrogen receptor modulators (SERMs) have been explored. We discuss the promises and challenges of utilizing topical estrogens, SERMs, and phytoestrogens in postmenopausal skin management.

The role of estrogen deficiency in skin ageing and wound healing

The links between hormonal signalling and lifespan have been well documented in a range of model organisms. For example, in C. elegans or D. melanogaster, lifespan can be modulated by ablating germline cells, or manipulating reproductive history or pregnenolone signalling. In mammalian systems, however, hormonal contribution to longevity is less well understood. With increasing age human steroid hormone profiles change substantially, particularly following menopause in women. This article reviews recent links between steroid sex hormones and ageing, with special emphasis on the skin and wound repair. Estrogen, which substantially decreases with advancing age in both males and females, protects against multiple aspects of cellular ageing in rodent models, including oxidative damage, telomere shortening and cellular senescence. Estrogen's effects are particularly pronounced in the skin where cutaneous changes post-menopause are well documented, and can be partially reversed by classical Hormone Replacement Therapy (HRT). Our research shows that while chronological ageing has clear effects on skin wound healing, falling estrogen levels are the principle mediator of these effects. Thus, both HRT and topical estrogen replacement substantially accelerate healing in elderly humans, but are associated with unwanted deleterious effects, particularly cancer promotion. In fact, much current research effort is being invested in exploring the therapeutic potential of estrogen signalling manipulation to reverse age-associated pathology in peripheral tissues. In the case of the skin the differential targeting of estrogen receptors to promote healing in aged subjects is a real therapeutic possibility.

Iron sensitizes keratinocytes and fibroblasts to UVA-mediated matrix metalloproteinase-1 through TNF-α and ERK activation

Oestrogen deficiency is regarded as the main causative factor in postmenopausal skin ageing and photoageing. While women after menopause experience low levels of oestrogen because of cease of ovarian function, they are also exposed to high levels of iron as a result of cessation of menstruation. In this study, we investigated whether this increase in iron presents a risk to the postmenopausal skin. Because of the lack of appropriate animal models to closely mimic the low oestrogen and high iron conditions, we tested the hypothesis in a high iron and low oestrogen culture model. Here, we showed that primary human dermal fibroblasts exposed to iron did not affect the baseline levels of matrix metalloproteinase-1 (MMP-1) activity. However, the iron-exposed fibroblasts were sensitized to UVA exposure, which resulted in a synergistic increase in MMP-1. UVA activated the three members of MAPK family: ERKs, p38, and JNKs. Additional activation of ERKs by iron contributed to the synergistic increases. Primary normal human epidermal keratinocytes (NHEK) did not respond to iron or UVA exposure as measured by MMP-1, but produced tumor necrosis factor-alpha (TNF-α) in the media, which then stimulated MMP-1 in fibroblasts. Our results indicate that iron and UVA increase MMP-1 activity in dermal fibroblasts not only directly through ERK activation but also by an indirect paracrine loop through TNF-α released by NHEK. We conclude that in addition to oestrogen deficiency, increased iron as a result of menopause could be a novel risk factor by sensitizing postmenopausal skin to solar irradiation.

Human dermal fibroblast proliferation activity of usimine-C from Antarctic lichen Ramalina terebrata

Type I collagen is the major structural protein in dermis and its presence is used to monitor skin cell proliferation and aging. Recently, novel usimine compounds have been found in the Antarctic lichen Ramalina terebrata. In the present study, usimine-C induced cell proliferation of human dermal fibroblast, CCD-986SK, up to 1.6-fold after treating with 90 microg/ml for 48 h. Type I procollagen synthesis was significantly increased 1.3-fold, 3-fold, and 5-fold after treating with 0.14, 0.72, and 3.6 microg usimine-C/ml for 24 h, respectively, whereas no significant increase in type I procollagen was observed after treating with usimine-A or -B. Usimines are usnic acid derivatives. Considering that the difference among the derivatives is a side chain, the proliferation activity may be related to this side chain, triggering an internal signal for type I procollagen expression. Further studies still remain to clarify the signaling pathways for the type I procollagen induction, which is activated by usimine-C.

The skin, carotid and intervertebral disc: making the connection!

A fairly consistent finding in work on the menopause and hormone replacement therapy is the positive effect of estrogen on connective tissue and its turnover. The menopause has been shown repeatedly to have a negative effect on the connective tissue in the dermis of the skin. Such an effect is prevented and in some cases reversed with estrogen therapy. This is similar to what happens in bone matrix. Similarly, the media in the carotid has been shown to undergo the same change with the menopause and with estrogen therapy as the dermis. The carotid artery media is increased in menopausal women on estrogen therapy and is thinner in untreated women. Recently, new information has revealed that the menopause, i.e. estrogen deprivation, has similar effects on the connective tissue of intervertebral discs. In aged intervertebral discs, the predominant collagen is type III, not type I, which is the predominant collagen in skin and bone, although skin has additional type III. These negative changes are once again prevented or reversed with estrogen therapy. This effect probably also extends to the extracellular non-collagenous matrix in all these systems, i.e. skin, carotid and intervertebral discs. The common thread is that estrogen has profound effects on connective tissue turnover, no matter the site. This has far-reaching implications not only in maintaining the structure and aesthetic appearance of tissue, but also the strength and stiffness of various tissues and the functioning of neighboring and surrounding organs.

Effect of estrogens on skin aging and the potential role of selective estrogen receptor modulators

Estrogens have a profound influence on skin. The relative hypoestrogenism that accompanies menopause exacerbates the deleterious effects of both intrinsic and environmental aging. Estrogens prevent skin aging. They increase skin thickness and improve skin moisture. Beneficial effects of hormone replacement therapy (HRT) on skin aging have been well documented, but HRT cannot obviously be recommended solely to treat skin aging in menopausal women. Topical estrogen application is highly effective and safe if used by a dermatologist with expertise in endocrinology. The question of whether estrogen alternatives such as phytoestrogens and selective estrogen receptor modulators are effective estrogens for the prevention of skin aging in postmenopausal women remains unanswered. However, preliminary data indicate that such treatment may be of benefit for skin aging treatment.