Type III collagen content in the skin of postmenopausal women receiving oestradiol and testosterone implants

Oral Supplementation and Systemic Drugs for Skin Aging: A Narrative Review

Skin aging is influenced by intrinsic and extrinsic factors and involves multiple pathogenic mechanisms. The most widely used treatments are topical products and minimally invasive procedures. Evidence on the benefits of systemic therapy is limited for several reasons: Reliance on mostly small and predominantly female samples, short study durations, methodologic heterogeneity, and a lack of consensus on which outcome measures are clinically relevant. Furthermore, systemic drugs and oral supplements are not without adverse effects. Oral hydrolyzed collagen and oral hyaluronic acid are well tolerated, and numerous clinical trials show they can mitigate some signs of skin aging. Low-dose oral isotretinoin is another option, but it has a higher risk of adverse effects. Evidence is lacking on the effects of the many dietary supplements on offer, such as vitamins, flavonoids, plant extracts, and trace elements. The future of skin aging management would appear to lie in the use of senolytic and senomorphic agents targeting senescent cells in the skin.

[Translated article] Oral Supplementation and Systemic Drugs for Skin Aging: A Narrative Review

Skin aging is influenced by intrinsic and extrinsic factors and involves multiple pathogenic mechanisms. The most widely used treatments are topical products and minimally invasive procedures. Evidence on the benefits of systemic therapy is limited for several reasons: reliance on mostly small and predominantly female samples, short study durations, methodologic heterogeneity, and a lack of consensus on which outcome measures are clinically relevant. Furthermore, systemic drugs and oral supplements are not without adverse effects. Oral hydrolyzed collagen and oral hyaluronic acid are well tolerated, and numerous clinical trials show they can mitigate some signs of skin aging. Low-dose oral isotretinoin is another option, but it has a higher risk of adverse effects. Evidence is lacking on the effects of the many dietary supplements on offer, such as vitamins, flavonoids, plant extracts, and trace elements. The future of skin aging management would appear to lie in the use of senolytic and senomorphic agents targeting senescent cells in the skin.

Chemical Composition of Salix koreensis Anderss Flower Absolute and Its Skin Wound Healing Activities In Vitro

Salix koreensis Anderss (SKA) has been used traditionally to treat inflammation, pain, and edema. SKA has anti-inflammatory and antioxidant effects, but no study has examined its effects on skin wound healing. Here, we aimed to investigate the effects of the absolute extracted from SKA flower (SKAFAb) on skin wound healing-associated responses in keratinocytes. SKAFAb was produced using a solvent extraction method and its chemical composition was analyzed by gas chromatography/mass spectrometry. The effects of SKAFAb on HaCaT cells (a human epidermal keratinocyte cell line) were investigated using a Boyden chamber and 5-bromo-2′-deoxyuridine incorporation, sprout outgrowth, immunoblotting, enzyme-linked immunosorbent, and water-soluble tetrazolium salt assays. Sixteen constituents were identified in SKAFAb. SKAFAb promoted HaCaT cell proliferation, migration, and type I and IV collagen productions. SKAFAb increased sprout outgrowth and increased the phosphorylations of serine/threonine-specific protein kinase (Akt), c-Jun NH2-terminal kinase, extracellular signal-regulated kinase1/2, and p38 mitogen-activated protein kinase (MAPK) in HaCaT cells. These results indicate that SKAFAb promotes keratinocyte proliferation and migration, probably by activating Akt and MAPK signaling pathways, and induces collagen synthesis in keratinocytes. SKAFAb may be a promising material for promoting skin wound healing.

Positive Promoting Effects of Smilax China Flower Absolute on the Wound Healing/Skin Barrier Repair-Related Responses of HaCaT Human Skin Keratinocytes

Smilax china (SC) has pharmacological effects including anti-inflammatory activity, but its effects on skin wound healing and skin barrier function have not been investigated. Here, we investigated the effects of absolute extracted from SC flowers (SCF) on skin wound healing-linked responses and functional skin barrier proteins using human epidermal keratinocytes (HaCaT cells). SCF absolute contained 20 components and was non-toxic to HaCaT cells. The absolute increased the proliferation, migration, and sprout outgrowth of HaCaT cells, and enhanced the activations of serine/threonine-specific protein kinase and extracellular signal-regulated kinase1/2. In addition, it increased the syntheses of type I and IV collagens and the expressions of skin barrier proteins (filaggrin and loricrin). These results indicate SCF absolute may has positive effects on skin wound healing by accelerating keratinocyte migration and proliferation activities and collagen synthesis, and on skin barrier function by upregulating barrier proteins in keratinocytes. We suggest SCF absolute to be considered as a potential means of promoting skin wound and barrier repair.

Management of skin thinning and aging: review of therapies for neocollagenesis; hormones and energy devices

BACKGROUND

Hormone replacement therapy and various devices exist to treat signs of aging, such as skin thinning, yet there are no reviews summarizing or evaluating their role in neocollagenesis and the associated increase in skin thickness.

OBJECTIVE

To review the literature regarding stimulation and generation of new collagen in the dermis in two parts. Part 2 reviews oral and topical hormone replacement therapy as well as energy-based devices.

METHODS

The PubMed database was searched for related literature. Studies involving the use of hormone supplements and energy devices with a resultant change in collagen production or skin thickness were obtained and reviewed for evidence.

RESULTS

Hormones, including estrogen, testosterone, and dehydroepiandrosterone, and human growth hormone have been reported with substantiating evidence for neocollagenesis and dermal thickening. Energy devices, including radiofrequency, ultrasound, and laser therapy, have also been reported to stimulate neocollagenesis.

LIMITATIONS

The results presented in certain literature are not based on randomized controlled trials.

CONCLUSION

Hormone deficient individuals can regain skin thickness with hormone replacement therapy. Dermal heating can provide a substantial amount of neocollagenesis; however, laser technology, specifically CO₂ , appears to be the most effective at increasing skin collagen and tightening.

Estrogen deficiency - a central paradigm in age-related impaired healing?

Wound healing is a dynamic biological process achieved through four sequential, overlapping phases; hemostasis, inflammation, tissue proliferation and remodeling. For effective wound healing, all four phases must occur in the appropriate order and time frame. It is well accepted that the wound healing process becomes disrupted in the elderly, increasing the propensity of non-healing wound states that can lead to substantial patient morbidity and an enormous financial burden on healthcare systems. Estrogen deprivation in the elderly has been identified as the key driver of age-related delayed wound healing in both genders, with topical and systemic estrogen replacement reversing the detrimental effects of aging on wound repair. Evidence suggests estrogen deprivation may contribute to the development of chronic wound healing states in the elderly but research in this area is somewhat limited, warranting further investigations. Moreover, although the beneficial effects of estrogen on cutaneous healing have been widely explored, the development of estrogen-based treatments to enhance wound repair in the elderly have yet to be widely exploited. This review explores the critical role of estrogen in reversing age-related impaired healing and evaluates the prospect of developing more focused novel therapeutic strategies that enhance wound repair in the elderly via activation of specific estrogen signaling pathways in regenerating tissues, whilst leaving non-target tissues largely unaffected.

Stimulatory Effects of Paederia foetida Flower Absolute on the Skin Wound and Barrier Repair Activities of Keratinocytes

Paederia foetida (PF) has antidiarrheal, antidiabetic, and anti-inflammatory activities. However, its biological activities on skin remain unclear. In this study, we examined the effect of PF flower absolute (PFFA) on skin wound healing- and skin barrier-linked responses in human epidermal keratinocytes (HaCaT cells). PFFA contained 23 components and increased the proliferation and sprout outgrowth of HaCaT cells and modestly increased migration. PFFA enhanced the phosphorylation levels of extracellular signal-regulated kinase1/2, serine/threonine-specific protein kinase (AKT), and p38 mitogen-activated protein kinase (MAPK) in HaCaT cells, and upregulated type I and IV collagen synthesis and filaggrin (an epidermal barrier protein) expression in HaCaT cells. These findings suggest PFFA may promote skin wound repair by stimulating migratory and proliferative activities (probably through the AKT/MAPK pathway), collagen synthesis, and skin barrier repair by upregulating the expressions of filaggrin in epidermal keratinocytes. Therefore, PFFA may be useful for developing agents that enhance skin wound and barrier-repair functions.

The role of bioidentical hormone replacement therapy in anti-aging medicine: a review of the literature

The changes in skin and overall appearance that occur with increasing age can be partly attributed to declining hormone levels. While hormonal deficiencies are most commonly associated with postmenopausal females, males are also subject to age-related testosterone decline and may benefit from replacement of deficient hormones. However, great disparities exist between the recommendations of scientific societies and actual use of hormone supplements in aging patients. The purpose of this literature review is to discuss the role of hormones in the aging process of the skin, explain the safety profile of hormone replacement therapy, specifically discussing the superiority of bioidentical hormones, and highlight the benefits of hormone replacement in anti-aging of the skin. In summary, this literature review suggests that hormone replacement with bioidentical hormones is a safe and effective way to prevent skin aging.

Potential Wound Healing Activities of Galla Rhois in Human Fibroblasts and Keratinocytes

Wound healing is a complex process orchestrated by the regeneration of the epithelium and the remodeling of the extracellular matrix through processes like collagen deposition. Galla Rhois has been widely used in traditional Korean medicine for its various pharmacological effects, including an anticoccidial effect, however, little is known about its healing activity. The purpose of this study was to determine the effects of Galla Rhois ethanol extract (GRE) on wound healing activities, including H2O2-induced oxidative stress, cell migration, and lactate dehydrogenase (LDH) release assays using human keratinocyte (HaCaT) and dermal fibroblasts (CCD-986SK). In addition, total soluble collagen deposition and collagen gene expression for Type I and III collagen were evaluated in CCD-986SK. Total tannin and flavonoid contents for GRE were measured. GRE induced a significant increase in the number and migration of cells, along with a decrease in cell death and LDH release. In addition, it also induced the over-expression of collagen Type I and III mRNA and caused increased synthesis of total soluble collagen. The contents of total tannin and flavonoid for GRE were 55.7% ([Formula: see text][Formula: see text]mg/g) and 62.9% ([Formula: see text][Formula: see text]mg/g), respectively. The results suggest that GRE can cause accelerated wound healing by increasing cell survival, proliferation, migration, and collagen synthesis along with a potential anti-oxidant property. This evidence provides novel insight into natural therapy for tissue injury.

Estrogens and aging skin

Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity. Its protective function becomes compromised and aging is associated with impaired wound healing, hair loss, pigmentary changes and skin cancer.

 

Skin aging can be significantly delayed by the administration of estrogen. This paper reviews estrogen effects on human skin and the mechanisms by which estrogens can alleviate the changes due to aging. The relevance of estrogen replacement, selective estrogen receptor modulators (SERMs) and phytoestrogens as therapies for diminishing skin aging is highlighted. Understanding estrogen signaling in skin will provide a basis for interventions in aging pathologies.

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.

Postmenopausal skin and estrogen

The aging global population continues to drive increasing demand for cosmaceuticals and cosmetic surgery among older men and women. Since the discovery in the 1990s that estrogen receptors are present in skin cells and decline in number from the onset of menopause in women, researchers have explored a number of ways in which estrogen can improve skin condition. Skin is estrogen responsive, and several studies now exist to support the antiaging properties of estrogen replacement therapies in postmenopausal women. Both systemic and topical estrogens appear to have positive effects on hormonal aging, increasing skin collagen content, thickness, elasticity and hydration. Estrogen therapies may also improve wound healing and reduce the incidence of wound complications. This review explores the potential for targeted estrogen replacement as a therapeutic option for long-term skin management in postmenopausal women.

Sex hormone regulation of collagen concentrations in cranial cruciate ligaments of sexually immature male rabbits

OBJECTIVE

To investigate the effects of gonadectomy on collagen homeostasis in cranial cruciate ligaments of male rabbits.

ANIMALS

30 sexually immature (16-week-old) male New Zealand White rabbits.

PROCEDURES

Rabbits were randomly assigned to 5 groups of 6 rabbits each: sexually intact, placebo (control group); castrated, placebo; castrated, testosterone; castrated, dihydrotestosterone; and castrated, 17β-estradiol (E(2)). Control rabbits underwent a sham operation, and all other rabbits underwent gonadectomy. At the time of gonadectomy, the placebo and sex hormones were administered via slow-release pellets implanted subcutaneously as assigned. After 21 days of hormone supplementation, measurements were obtained of serum testosterone and E(2) concentrations, ligament collagen characteristics, and androgen receptor, estrogen receoptor α, and matrix metalloproteinase expression.

RESULTS

Following gonadectomy and hormone supplementation, the treatment groups differed in serum testosterone and E(2) concentrations to various degrees. Collagen concentrations were lower and fiber diameters higher in the absence of sex hormones, in association with the degrees of estrogen receptor a and androgen receptor expression. Although differences were detected among the groups in matrix metalloproteinase expression, these differences were not significant.

CONCLUSIONS AND CLINICAL RELEVANCE

Sex hormones appeared to play a role in cranial cruciate ligament homeostasis in male rabbits. Physiologic changes triggered by the lack of sex hormones following gonadectomy in sexually immature rabbits may potentially predispose those rabbits to orthopedic injuries.

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.

Sex, collagen expression, and anterior cruciate ligament strength in rats

CONTEXT

Sex-specific responses to steroid sex hormones have been suggested as a potential cause for the disparate anterior cruciate ligament (ACL) injury rates between male and female athletes. Type 1 collagen (T1C) and type 3 collagen (T3C) are crucial structural components that define the ligament's ability to withstand tensile loads. Messenger RNA (mRNA) is an important mediator of downstream collagen synthesis and remodeling, but the sex-specific mechanisms of collagen mRNA expression and ACL strength are unknown.

OBJECTIVE

To examine the influence of sex on T1C and T3C mRNA expression and mass-normalized stiffness and peak failure load in the ACLs of skeletally mature rats.

DESIGN

Observational study.

SETTING

Basic sciences and biomechanical testing laboratories.

PATIENTS OR OTHER PARTICIPANTS

Nineteen 12-week-old male (n = 9) and female (n = 10) Sprague Dawley rats.

MAIN OUTCOME MEASURE(S)

We used real-time polymerase chain reaction to determine T1C and T3C mRNA expression and a hydraulic materials testing device to measure ACL stiffness and failure load. Nonparametric Wilcoxon rank sum tests were used to compare the groups.

RESULTS

Female rats had lower amounts of T3C mRNA expression and higher normalized ACL tangent stiffness and failure load than male rats.

CONCLUSIONS

These findings suggest that sex-specific differences in T1C and T3C mRNA expression may play an important role in the downstream mechanical properties of the ACL.

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.

Physiological changes associated with the menstrual cycle: a review

The cyclic hormonal changes that regulate the menstrual cycle are a significant biological influence on the female body, one with both physical and emotional ramifications. Menstruation is governed by tightly orchestrated changes in the levels of ovarian estrogen and progesterone, which produce varying responses in diverse tissues and organs. The skin, the largest organ in the body, is replete with estrogen receptors (in both dermis and epidermis) and to a lesser extent, progesterone receptors. Cyclically fluctuating levels of estrogen and progesterone influence numerous characteristics of the epidermis, including skin surface lipid secretion and sebum production, skin thickness, fat deposition, skin hydration, and barrier function. Dermal collagen content, which contributes to skin elasticity and resistance to wrinkling, is also influenced. Interestingly, estrogen levels also influence skin pigmentation and UV susceptibility, as well as resident microflora. In addition, changing hormone levels across the menstrual cycle produce measurable variations in immune function and disease susceptibility. An understanding of the profound influence that fluctuating estrogen and progesterone levels have on the biological responses of the premenopausal adult woman is critical to optimizing the efficacy of medical therapies in this population.

Skin treatments and dermatological procedures to promote youthful skin

The skin, the largest organ of the body, is the organ in which changes associated with aging are most visible. With increasing frequency, patients are requesting information and treatments that improve the appearance of their skin. Corresponding to this trend, there is an increasing number of products and methods available that claim to aid this pursuit. First, a change of the patient's lifestyle (eg, sun behavior, nicotine abuse, and nutrition) must take place. Only then may other methods be used. This article reflects on the following topics: topical retinoids, peels, botulinum neurotoxin, soft tissue fillers, lasers, topical and systemic endocrinological therapies, and phytohormones. A thorough knowledge of the properties (benefits, limitations, and complications) of the expanding array of possibilities for rejuvenation of the skin is essential for any physician treating patients with cosmetic complaints.

A prospective, randomized, double-blind, placebo-controlled study on the influence of a hormone replacement therapy on skin aging in postmenopausal women

BACKGROUND

There is mounting evidence that menopause affects some functions of the skin. Hormone replacement therapy (HRT) appears to limit some of the climacteric aspects of cutaneous aging.

OBJECTIVE

In the light of a growing interest in the endocrinological influence of skin, we performed a study evaluating the effects of HRT on skin aging in postmenopausal women.

METHODS

Forty non-hysterectomized, postmenopausal women were included in this prospective, randomized, double-blind, placebo-controlled study on the influence of oral sequential treatment with a combination of 2 mg 17beta-estradiol/10 mg dydrogesterone (Femoston) for seven 28-day cycles. Skin elasticity, skin surface lipids, skin hydration and skin thickness were measured by non-invasive methods, and both adverse-event profile and clinical-dermatological status were evaluated.

RESULTS

After 7 months of HRT, skin elasticity increased significantly at the right ramus of the mandible, while skin hydration tended to improve significantly at the right upper arm (inner side); skin thickness improved significantly but skin surface lipids did not. Absolute effects did not differ significantly between HRT and placebo patients. A dermatological evaluation was largely consistent with measurement results. Safety and tolerability of HRT were positive.

CONCLUSION

The results showed improvements in the parameters involved in skin aging in the HRT group as compared to baseline. While skin aging is no indication for systemic hormone supplementation, a positive effect on aging skin can be observed.

Effect of estrogens on skin aging and the potential role of SERMs

In humans, structural and functional changes attributable to aging are more visibly evident in the skin than in any other organ. Estrogens have significant effects on skin physiology and modulate epidermal keratinocytes, dermal fibroblasts and melanocytes, in addition to skin appendages including the hair follicle and the sebaceous gland. Importantly, skin aging can be significantly delayed by the administration of estrogen. This paper reviews the effects of estrogens on skin and the mechanisms by which estrogens can alleviate the changes due to aging that occur in human skin. The relevance of estrogen replacement therapy (HRT) in postmenopausal women and the potential value of selective estrogen receptor modulators (SERMs) as a therapy for diminishing skin aging are also highlighted.

Skin climacteric aging and hormone replacement therapy

A gender perspective is indispensable for a full understanding of aging. Menopause is a turning point in women's lives. In addition to the effects of chronological aging, sunlight exposure, and other environmental and endogenous stimuli, the climacteric appears to exert some dramatic consequences on skin biology and aspect. The epidermis may become xerotic and exhibit altered functions. The dermis thins out and its elasticity decreases in concert with the decline in bone mass. The skin microcirculation is impaired. These aspects are some of the better worked-out changes of the climacteric, which in turn seem to be stabilized or in part reversible with hormone replacement therapy (HRT). The HRT effect on menopause consequences on hair growth and sebum production is less impressive. This review summarizes some important impacts of the climacteric on skin, and highlights the benefits of HRT that may influence cosmetic dermatology.

A dermatologist's opinion on hormone therapy and skin aging

The Taylor et al. study in this issue suggests that long-term hormone replacement therapy helps prevent skin aging. All patients interested in preventing skin aging should regularly use sunscreens, retinoids, and oral or topical antioxidants.

Uterosacral ligament in postmenopausal women with or without pelvic organ prolapse

The uterosacral ligaments are thought to contribute to pelvic support. The objective of this study was to compare the structural components of these ligaments in women with and without pelvic organ prolapse (POP). We characterized uterosacral ligaments of 25 postmenopausal women with POP and 16 controls histomorphologically and immunohistochemically by quantifying their content of collagen I, III, and smooth muscle using a computerized image analysis. In 84% the uterosacral ligaments were composed of more than 20% of smooth muscle cells. There was no difference in collagen I expression and smooth muscle cell amount between women with POP and those without. In contrast, the collagen III expression was significantly related to the presence of POP (p<0.001) rather than age or parity. Our findings suggest that the higher collagen III expression might be a typical characteristic of POP patients' connective tissue. The considerable amount of smooth muscle cells in uterosacral ligaments may provide pelvic support.

Regulatory roles of sex hormones in cutaneous biology and immunology

Recent studies have revealed that sex hormones manifest a variety of biological and immunological effects in the skin. Pregnancy, menstruation and the menopause modulate the natural course of psoriasis, indicating a female hormone-induced regulation of skin inflammation. Estrogen in vitro down-regulates the production of the neutrophil, type 1 T cell and macrophage-attracting chemokines, CXCL8, CXCL10, CCL5, by keratinocytes, and suppresses IL-12 production and antigen-presenting capacity while enhancing anti-inflammatory IL-10 production by dendritic cells. These data indicate that estrogen may attenuate inflammation in psoriatic lesions. Estrogen, alone or together with progesterone, prevents or reverses skin atrophy, dryness and wrinkles associated with chronological or photo-aging. Estrogen and progesterone stimulate proliferation of keratinocytes while estrogen suppresses apoptosis and thus prevents epidermal atrophy. Estrogen also enhances collagen synthesis, and estrogen and progesterone suppress collagenolysis by reducing matrix metalloproteinase activity in fibroblasts, thereby maintaining skin thickness. Estrogen maintains skin moisture by increasing acid mucopolysaccharide or hyaluronic acid levels in the dermis. Progesterone increases sebum secretion. Estrogen accelerates cutaneous wound healing stimulating NGF production in macrophages, GM-CSF production in keratinocytes and bFGF and TGF-beta1 production in fibroblasts, leading to the enhancement of wound re-innervation, re-epithelialization and granulation tissue formation. In contrast, androgens prolong inflammation, reduce deposition of extracellular matrix in wounds, and reduce the rate of wound healing. Estrogen enhances VEGF production in macrophages, an effect that is antagonized by androgens and which may be related to the development of granuloma pyogenicum during pregnancy. These regulatory effects of sex steroids may be manipulated as therapeutic or prophylactic measures in psoriasis, aging, chronic wounds or granuloma pyogenicum.

Skin aging and sex hormones in women - clinical perspectives for intervention by hormone replacement therapy

The skin, the largest organ of the body, is the organ in which changes associated with aging are most visible. The skin is a target organ for various hormones, and sex steroids have a profound influence on the aging process. A decrease in sex steroids thus induces a reduction of those skin functions that are under hormonal control. Keratinocytes, Langerhans' cells, melanocytes, sebaceous glands, collagen content and the synthesis of hyaluronic acid, for example, are under hormonal influence. Topical application of estrogens has a positive effect on skin aging parameters, whilst numerous studies have also shown the positive influence of systemic hormone replacement therapy on skin aging. As an alternative treatment, phytohormones may be administered, with the structural similarity to 17beta-estradiol explaining their estrogen-like effects. However, isoflavonoids exhibit an inferior biological potency to synthetic estrogens. Although a large number of publications have documented the effects of sex hormones on the aging process, it is obvious that hormone replacement should not be administered as an independent treatment for skin aging.

Oestrogens and the skin

Oestrogen loss at the menopause has a profound influence on skin. Oestrogen treatment in post-menopausal women has repeatedly been shown to increase collagen content, dermal thickness and elasticity. Data on the effect of oestrogen on skin water content are also promising. Further, physiological studies on oestrogen and wound healing suggest that hormone replacement therapy (HRT) may play a beneficial role in cutaneous injury repair. Results of the effect of HRT on other physiological characteristics of skin, such as elastin content, sebaceous secretions, wrinkling and blood flow, are discordant. Given the responsiveness of skin to oestrogen, the effects of HRT on ageing skin require further examination and careful molecular studies will probably clarify oestrogen's effects at the cellular level.

Skin aging and menopause : implications for treatment

The skin is one of the largest organs of the body, which is significantly affected by the aging process and menopause. The significant changes sustained by the skin during the menopause are due to the effect sustained on the skin's individual components. The estrogen receptor has been detected on the cellular components of the skin. Accordingly, dermal cellular metabolism is influenced by the hypoestrogenoemic state of menopause leading to changes in the collagen content, alterations in the concentration of glycoaminoglycans and most importantly the water content. Consequently changes in these basic components leads to an alteration in function compatible with skin aging. Changes in the skin collagen leads to diminished elasticity and skin strength. Collagen content may be measured by various methods such as direct skin biopsy, skin blister assessment for collagen markers and skin thickness measurement. All these variables indicate a reduction in collagen content following menopause. This may be reversed with the administration of estrogen given both topically and systemically.A reduction in hydrophilic glycoaminglycans leads to a direct reduction in water content, which influences the skin turgor. These effects on glycoaminoglycans, due to the hypoestrogenia, have been clearly shown in animal studies and appeared to be rapidly reversed with the application of estrogens. The sum total of these basic effects on the skin leads to wrinkles, the skin condition typifying skin aging.Structures resident in the skin are likewise influenced by menopause. Changes to the cutaneous vascular reactivity are noted following menopause. Capillary blood flow velocity decreases significantly in postmenopausal women. Postmenopausal flushing is due to profound vasodilatation in the dermal papillae. Hair growth is also influenced by the hormonal milieu and consequently hair loss has been associated with the beginning of menopause. Treatments administered for menopause, in particular hormone replacement therapy, appear to alter its effects on the basic components of the skin as well as the more complex structures residing in the skin, consequently retarding the skin aging process.

Oral contraceptives improve lung mechanics

OBJECTIVE

To determine whether oral contraceptives affect lung mechanics.

DESIGN

Open-label study.

SETTING

Academic medical center.

PATIENT(S)

Thirty-six healthy nonsmoking women.

INTERVENTION(S)

Administration of an oral contraceptive containing ethinyl estradiol, 35 microg, and norgestimat, 250 microg for 6 months.

MAIN OUTCOME MEASURE(S)

Forced vital capacity; forced expiratory volume in 1 second; peak expiratory flow; and flow at large, medium, and small lung volumes.

RESULT(S)

At 6 months, all forced expiratory flow and volume had increased significantly (from 6.5% to 15%). Flows at small lung volumes especially increased.

CONCLUSION(S)

Combination oral contraceptives have a measurable effect on lung mechanics.

Premenopausal women deposit more collagen than men during healing of an experimental wound

BACKGROUND

From a post hoc analysis a hypothesis was generated that women deposit more collagen in a surrogate test wound than men. The purpose of this study has been to verify this hypothesis prospectively in a controlled study.

METHODS

Post hoc analyses were done on 37 volunteers (study A). The prospective trial included 47 smoking volunteers (study B). Outcome measures were deposition levels of collagen (hydroxyproline) and protein during a period of 10 days in subcutaneously implanted tubes of expanded polytetrafluoroethylene.

RESULTS

The mean increments of collagen deposition levels in women as compared with men were 56% (P <.01) in study A and 74% (P <.001) in study B. The mean increase in the ratio collagen/total protein was 74% (P <.001) and 69% (P <.001), indicating that the increase was specific for collagen.

CONCLUSIONS

The studies show that deposition in a miniature subcutaneous test wound of collagen, but not noncollagenous protein, is promoted in women as compared to men. These findings may relate to the observation in some reports indicating higher rates of compromised postoperative wound healing in men.

The effect of oestradiol on vaginal collagen metabolism in postmenopausal women with genuine stress incontinence

OBJECTIVE

To determine whether oestrogen replacement will produce an improvement in the quantity, or quality, of pelvic collagen in postmenopausal women.

DESIGN

A prospective double-blind placebo controlled trial of oestrogen therapy.

SETTING

Southmead Hospital, Bristol, UK.

POPULATION

Fifty-five postmenopausal women with a urodynamic diagnosis of genuine urinary stress incontinence.

METHODS

Randomisation to a six-month, double-blind, placebo-controlled, trial of oestradiol valerate 2mg once daily. A 10mg-30mg periurethral biopsy was taken from the vaginal epithelium before and after treatment. Tissue was analysed for total collagen content, intermolecular cross-links, advanced glycation end-products, collagen type ratios and matrix metalloproteinase (MMP) activity.

RESULTS

Forty-nine women completed the trial of whom 26 received oestrogen and 23 received placebo. When compared with placebo, oestrogen treatment resulted in significant decreases in total collagen (P = 0.0054), the mature cross-link HHL (P = 0.0009) and the advanced glycation end-product NFC-1 (P = 0.0009). There was a significant rise in the immature cross-link HLKNL (P = 0.0191). Oestrogen produced a significant increase in MMP-2 expression (Pro MMP-2, P = 0.0017).

CONCLUSIONS

Six months treatment with oestrogen has profound effects upon pelvic collagen metabolism, stimulating collagen degradation via increased proteinase activity. While aged collagen is being lost, new collagen is synthesised as witnessed by the increase in the immature cross-links and the decrease in both mature cross-links and advanced glycation end-products. Collagen loss contradicts previous reports; perhaps aged collagen degradation is merely an early response to oestrogen stimulation. We have evidence of new collagen synthesis, and it may be that a longer treatment interval would show total collagen content increasing. Further studies within this field are warranted.

Estrogen and skin. An overview

As the population of postmenopausal women increases, interest in the effects of estrogen grows. The influence of estrogen on several body systems has been well-documented; however, one area that has not been explored is the effects of estrogen on skin. Estrogen appears to aid in the prevention of skin aging in several ways. This reproductive hormone prevents a decrease in skin collagen in postmenopausal women; topical and systemic estrogen therapy can increase the skin collagen content and therefore maintain skin thickness. In addition, estrogen maintains skin moisture by increasing acid mucopolysaccharides and hyaluronic acid in the skin and possibly maintaining stratum corneum barrier function. Sebum levels are higher in postmenopausal women receiving hormone replacement therapy. Skin wrinkling also may benefit from estrogen as a result of the effects of the hormone on the elastic fibers and collagen. Outside of its influence on skin aging, it has been suggested that estrogen increases cutaneous wound healing by regulating the levels of a cytokine. In fact, topical estrogen has been found to accelerate and improve wound healing in elderly men and women. The role of estrogen in scarring is unclear but recent studies indicate that the lack of estrogen or the addition of tamoxifen may improve the quality of scarring. Unlike skin aging, the role of endogenous and exogenous estrogen in melanoma has not been well established.

Hormonal effects on skin aging

With aging, there is a decrease in the level of hormones, such as estrogen, testosterone, dehydroepiandrosterone sulfate, and growth hormone. The effect of this decrease on the skin has been poorly documented, although more data are available for estrogen than for other hormones. This article reviews the effect of decreasing hormone levels on the skin and the possible cutaneous benefits of hormone replacement therapy.

Menopause and the skin

Women live one-third of their lives in the post-menopausal state. Significant hormonal alterations occur at the time of menopause, leading to a range of physiological disorders affecting multiple organ systems in the body. The effects of menopause on the skin have been underresearched. Many skin changes occur at the time of menopause and the cutaneous effects of hormone replacement therapy are significant. Menopausal changes in hormones may alter the biomechanical properties of the skin and certain disorders are more common in menopausal women, such as lichen sclerosus, atrophic vulvovaginitis, flushing and dysaesthetic vulvodynia. Hair and oral changes may also be associated. As the average life expectancy increases, dermatologists need to be familiar with skin diseases affecting women in this age group.

The expression of the gene encoding pro-alpha 1 chain of type I collagen in the skin of premenopausal and postmenopausal women

OBJECTIVES

The atrophic changes occurring in the skin of postmenopausal women are thought to depend mainly on the oestrogen deficiency secondary to loss of hormonal function of the ovaries. The hypothesis to be tested was whether decreased serum level of oestrogen in these women influences the expression of gene encoding pro-alpha1 chain of type I collagen.

STUDY DESIGN

The skin specimens from six premenopausal and six postmenopausal women were taken at the time of surgery. The expression of gene encoding pro-alpha1 chain of type I collagen was estimated using Dot-Blot hybridisation technique.

RESULTS

The expression of pro-alpha1 chain of type I collagen gene was shown in all cases. The level of expression was different in each sample and did not depend on ovarian hormonal function.

CONCLUSIONS

Our results indicate that atrophic changes in the skin of postmenopausal women probably do not depend on diminished expression of gene encoding pro-alpha1 chain of type I collagen.

Hormone replacement therapy and the skin

Estrogens have a profound influence on skin. The hypoestrogenism occurring after the menopause leads to measured deterioration in the skin. Estrogen receptors have been identified in the skin and the concentration of these receptors varies in the different parts of the body. Estrogen improves skin in more than one way, the collagen content and quality is improved, skin thickness is increased, while vascularisation is enhanced. The extracellular matrix responsible for the tone and appearance of the skin is also improved. It is not just the skin that shows an improvement with estrogen therapy but also skin appendages, such as hair. Estrogens have been shown to increase the hair follicle life cycle. Skin aging is not totally estrogen dependent because the ravages of age and the external environment play very important roles. The effects of estrogen on skin need further elucidation and with the emergence of newer techniques it is now possible to study more clearly the changes occurring at the cellular level. Estrogen replacement reverses the deleterious effect of estrogen deprivation on the skin, which is thus yet another organ that benefits from hormone replacement therapy.

The effects of systemic hormonal replacement therapy on the skin of postmenopausal women

OBJECTIVE

The aim of this study was to determine the effects of hormonal replacement therapy on the skin of postmenopausal women.

METHOD

Forty-one postmenopausal women were randomly allocated to receive either hormonal replacement (valerate estradiol--2 mg/day for 21 days and cyproterone acetate--1 mg/day for 10 days) or placebo, both in a cyclic scheme for 6 months. Neither patients nor investigators were aware of the group allocation. Histologic changes were evaluated by skin biopsy of the left upper arm at baseline and after 6 months of treatment, utilizing computerized image analysis to assess the ratio area of epidermis/basement membrane length (AE/BML), ratio area of keratin/basement membrane length (AK/BML) and collagen and elastic fibers content.

RESULT

Collagen content of the left upper arm increased after 6 months of treatment only in the hormonal group (+6.49%; P < 0.05). Other parameters did not present any significant alteration after treatment in both groups.

CONCLUSION

Hormonal replacement for climacterics increases skin collagen content.

Effects of postmenopausal hypoestrogenism on skin collagen

OBJECTIVE

The aim of our study was to evaluate the effect of aging and postmenopausal hypoestrogenism on skin collagen content.

METHODS

Thirty-two women (mean age 48.78 +/- 9.86; year +/- S.D., range 28-68), 14 in premenopause and 18 in postmenopause, underwent skin biopsies performed during laparotomic operation. The amount of collagen type I, III and type III/type I ratio was evaluated by immunohistochemistry and computerised image analysis, and was related to age and years of postmenopause.

RESULTS

In the postmenopausal patients, a significant (P < 0.01) decrease of percentage of skin collagen type I, type III and type III/type I ratio was observed in comparison to premenopausal women. The percentages of collagen type I, type III and type III/I ratio of all patients studied was significantly (P < 0.01) correlated with chronological age (r = 0.88, 0.89 and 0.61, respectively). Considering only postmenopausal subjects, the correlation with chronological age was significant (P < 0.01) for collagen type I and type III of postmenopausal women (r = 0.59, r = 0.64, respectively), but not for the type III/I ratio (r = 0.37, P = 0.131). The percentages of collagen type I, type III and type III/I ratio of postmenopausal women showed a significant (P < 0.01) inverse correlation with years of postmenopause (r = 0.76, 0.73 and 0.73, respectively).

CONCLUSIONS

Our data suggest that the decrease of skin collagen is an estrogen-related phenomenon.

Trauma modifies strength and composition of retrodiscal tissues of the goat temporomandibular joint

OBJECTIVES

Temporomandibular pain is often accompanied by pathologic changes to joint retrodiscal tissues. The substantial representation of females in this condition has encouraged hypotheses which link genetic or hormonally induced abnormalities in tissue composition (type III collagen, type I collagen, type III/type I ratio) to the development of temporomandibular disorders. As this condition is often associated with a history of orofacial trauma, we investigated the functional impact of retrodiscal trauma on the composition and biomechanics of retrodiscal tissues.

DESIGN AND METHODS

Retrodiscal tissue of female goats received trauma or sham trauma. Following a healing period of 30 days, the tissues were pulled to failure on an extensometer.

OUTCOME MEASURES

Assessments were made of tissue biomechanical properties (failure force, elastic stiffness, strain distribution). Tissue fragments were assayed for collagens I and III.

RESULTS

Thirty days after surgical section of retrodiscal tissues, the tissue had reformed, but the composition and biomechanics were substantially changed. Healed tissue manifested less than half the strength of normal tissue (P = 0.02). In addition, the development of tissue strain shifted from a relatively even distribution to a confined region near the retrodiscal-discal attachment zone. It appeared that a large increase in the expression of type III collagen (179.6%; P = 0.038) and the ratio of type III/type I collagen (180.9%; P = 0.011) accounted for these functional changes.

CONCLUSIONS

We suggest that shifts in collagen expression following injury create shifts in strain development which focus tissue stresses near the interface of the disc and retrodiscal tissue, and that this shift dramatically weakens the tissue and increases the probability of re-injury, inflammation and pain.

The effect of hormone replacement therapy on carotid arteries: measurement with a high frequency ultrasound system

OBJECTIVE

To evaluate the effect of hormone replacement therapy (HRT) on carotid arteries in postmenopausal women with a high frequency ultrasound system.

METHODS

In a clinical cross-sectional study carotid artery layers were measured in 82 postmenopausal women receiving a sequential regimen of HRT (oestradiol valerate 2 mg and dydrogesterone 10 mg) and in 70 postmenopausal women without HRT. Measurements of the left carotid artery layers (externa, media, intima) were taken with a single mechanically activated 22.5-MHz transducer with an effective band width of 8 MHz.

RESULTS

A statistically significant increase in thickness of the media layer of the carotid artery was observed in the HRT group (0.34 +/- 0.06 mm) as compared to the untreated group (0.27 +/- 0.03 mm). The media/intima ratio of the treated group was statistically significantly higher than that of the untreated group (P < 0.05). The mean strength of the carotid wall was 0.70 +/- 0.17 mm in the 70 postmenopausal women without HRT and 0.76 +/- 0.24 mm in the 82 patients undergoing HRT.

CONCLUSION

HRT has a morphological effect on the carotid arteries in postmenopausal women. These findings support a cardioprotective effect, especially in terms of prevention of atherosclerosis. This effect can be measured non-invasively by high frequency ultrasound.