Extracellular matrix in cutaneous ageing: the effects of 0.1% copper-zinc malonate-containing cream on elastin biosynthesis

A Review of Midface Aging

PURPOSE

To review and summarize studies on the anatomy and involutional changes of the midface.

METHODS

A PubMed search was performed searching for studies on the anatomy and involutional changes concerning the midface.

RESULTS

The anatomy of the midface is complex. Studies of involutional change vary in scientific quality and have conflicting results. However, it appears that among the more common changes, there is a decrease in the maxillary and pyriform angle, with changes to the orbital floor position. Further, there appears to be an inferior migration of the fat compartments of the midface during aging, exacerbating the hollow of the palpebromalar groove and causing a deepening of the nasojugal groove. Changes to the volume of the buccal extension of the buccal fat pad exacerbate these changes and contribute to the gestalt changes associated with facial aging. Here, we review the major characteristics of soft tissue and bony changes on the midface, with special reference to their anatomic relationships.

CONCLUSIONS

The major findings characterizing midface aging are related largely to the soft tissue. However, more robust studies are required to quantify these changes and to appraise their impact on the overall manifestation of aging.

In Vitro and Ex Vivo Mechanistic Understanding and Clinical Evidence of a Novel Anti-Wrinkle Technology in Single-Arm, Monocentric, Open-Label Observational Studies

Skin aging is a biological process leading to visible skin alterations. The mechanism of action, clinical efficacy and tolerance of a novel anti-wrinkle technology were evaluated in two skin care products formulated for different skin types. Two single-arm monocentric, open-label observational clinical studies, which were 56 days long, evaluated a cream-gel (n = 30) and a cream (n = 33) on the face and neck. Morphometric analyses of five types of wrinkles were performed at 0, 7, 28 and 56 days. Structural changes in extracellular matrix (ECM) including collagen, elastin and hyaluronic acid (HA) were visualized and quantified by histochemical imaging after daily treatment of skin explants for 6 days. Protein and gene expression related to barrier and hydration were analyzed using ELISA and qRT-PCR, respectively, in a reconstituted human skin model treated daily for 48 h. A decrease in wrinkle dimensions was found in the majority of parameters after 28 days of treatment. Collagen, elastin, HA, procollagen type I, hyaluronan synthases, HAS2 and HAS3 were all stimulated. Based on significant and consistent changes in our investigations, we conclude that the underlying mechanism of action of the novel anti-wrinkle technology could be the remodeling of dermal ECM, and both the test formulations were efficacious and well tolerated.

Clinical Relevance of Elastin in the Structure and Function of Skin

Elastin is the main component of elastic fibers, which provide stretch, recoil, and elasticity to the skin. Normal levels of elastic fiber production, organization, and integration with other cutaneous extracellular matrix proteins, proteoglycans, and glycosaminoglycans are integral to maintaining healthy skin structure, function, and youthful appearance. Although elastin has very low turnover, its production decreases after individuals reach maturity and it is susceptible to damage from many factors. With advancing age and exposure to environmental insults, elastic fibers degrade. This degradation contributes to the loss of the skin's structural integrity; combined with subcutaneous fat loss, this results in looser, sagging skin, causing undesirable changes in appearance. The most dramatic changes occur in chronically sun-exposed skin, which displays sharply altered amounts and arrangements of cutaneous elastic fibers, decreased fine elastic fibers in the superficial dermis connecting to the epidermis, and replacement of the normal collagen-rich superficial dermis with abnormal clumps of solar elastosis material. Disruption of elastic fiber networks also leads to undesirable characteristics in wound healing, and the worsening structure and appearance of scars and stretch marks. Identifying ways to replenish elastin and elastic fibers should improve the skin's appearance, texture, resiliency, and wound-healing capabilities. However, few therapies are capable of repairing elastic fibers or substantially reorganizing the elastin/microfibril network. This review describes the clinical relevance of elastin in the context of the structure and function of healthy and aging skin, wound healing, and scars and introduces new approaches being developed to target elastin production and elastic fiber formation.

Bioactive Compounds for Skin Health: A Review

Human skin is continually changing. The condition of the skin largely depends on the individual’s overall state of health. A balanced diet plays an important role in the proper functioning of the human body, including the skin. The present study draws attention to bioactive substances, i.e., vitamins, minerals, fatty acids, polyphenols, and carotenoids, with a particular focus on their effects on the condition of the skin. The aim of the study was to review the literature on the effects of bioactive substances on skin parameters such as elasticity, firmness, wrinkles, senile dryness, hydration and color, and to define their role in the process of skin ageing.

Inorganic ions in the skin: Allies or enemies?

Skin constitutes a barrier protecting the organism against physical and chemical factors. Therefore, it is constantly exposed to the xenobiotics, including inorganic ions that are ubiquitous in the environment. Some of them play important roles in homeostasis and regulatory functions of the body, also in the skin, while others can be considered dangerous. Many authors have shown that inorganic ions could penetrate inside the skin and possibly induce local effects. In this review, we give an account of the current knowledge on the effects of skin exposure to inorganic ions. Beneficial effects on skin conditions related to the use of thermal spring waters are discussed together with the application of aluminium in underarm hygiene products and silver salts in treatment of difficult wounds. Finally, the potential consequences of dermal exposure to topical sensitizers and harmful heavy ions including radionuclides are discussed.

Sorocea guilleminiana Gaudich.: Wound healing activity, action mechanisms, and chemical characterization of the leaf infusion

ETHNOPHARMACOLOGICAL RELEVANCE

Sorocea guilleminina Gaudich. is a tree or shrub endemic to Brazil. Its leaves are used in Brazilian folk medicine for the healing of wounds, stomach problems, inflammation and as diuretic. The present study evaluates the activity and action mechanisms of the healing properties of the aqueous extract of S. guilleminiana leaves (AESg), in experimental models in vivo and in vitro, as well as performs a phytochemical analysis of the extract.

MATERIALS AND METHODS

The AESg was prepared by infusion: Ten g of dry leaves powder in 1 L hot water, soaked for 15 min, filtered, lyophilized, and stored at -30 °C. Phytochemical analyses were realized by colorimetry and HPLC/ESI/MS. Its' in vitro cytotoxicity was evaluated on fibroblastic N3T3 cells. The potential of the wound healing activity in vivo was evaluated using excision and incision wound rat models, by histopathology of the injured skin along with the determination of nitric oxide, cytokines (IL-1β, IL-10, and TNF-α), and antioxidant parameters (GSH, MPO and CAT). In vitro wound healing activity was also demonstrated in scratched N3T3 cells, by measuring the proliferation/migration rate.

RESULTS

The phytochemical analysis of the AESg revealed a strong presence of polar compounds, especially flavonoids (4 majoritarian), as well as terpenes and/or sterols (2 majoritarian). The AESg showed no toxicity in the N3T3 cell line (IC₅₀ > 800 μg/mL). Topical treatment with the AESg showed an increase (p < 0.05) in wound contraction with 2 mg/g cream on days 5 and 9 (43.56% and 6.70% increase, respectively), and with 50 mg/g on days 7 and 9 (10.88% and 7.91%, respectively), compared to the vehicle (non-ionic neutral cream). Topical application of AESg (2 or 50 mg/g non-ionic cream) in incised wounds caused an increase in the force necessary for the rupture of the wound when compared to the vehicle group. No changes in cytokines (IL-1β, IL-10, or TNF-α) or NO accumulation was found with up to 50 mg/g AESg treatment. For antioxidant activity on the incision wound, an increase in GSH levels was denoted with the AESg use, at the lowest and highest dose (2 and 50 mg/g) by 75.86% and 61.20% respectively, when compared to the vehicle. Also, the CAT activity was accentuated by AESg at the highest dose (50 mg/g) by 85.87%. Finally, the AESg at all doses attenuated MPO activity significantly in the incision wound by 71.35%, 73.21%, 78.08%, respectively. In the scratch test on N3T3 cells, the treatment with AESg resulted also in an increase in fibroblast proliferation/migration rate, compared to the vehicle.

CONCLUSION

AESg is not cytotoxic. The results confirm the popular use of the leaf infusion of S. guilleminiana for the treatment of cutaneous wounds, possibly by stimulating the proliferation of fibroblasts with a consequent deposition of collagen, fastening rearrangement of collagen fibers, and greater transformation into myofibroblasts, essential in the healing process. Preliminary chemical analyzes of AESg revealed the presence mainly of phenolic compounds, being salicylic acid, gallic acid, pinocembrin and isoquercitrin the majoritarian ones.

Zinc-containing compounds for personal care applications

It is well-known that zinc ions are widely used in cosmetic products. Their popularity is associated with the multifunctional profile of Zn²⁺ , which is classified as an essential chemical element in the human body. This review examines numerous beneficial biological properties of zinc-containing compounds and classifies the compounds used in cosmetic products according to their functionality profile: antioxidant, sunscreen, anti-inflammatory, anti-pigmentation, anti-ageing, anti-acne, antimicrobial, anti-odour, cleansing or stabilizing activity. It also underlines the significance of zinc in enzymatic processes, which depends on the enzyme type acts as inhibitor or enzymatic stimulator. Moreover, the article describes the chemical nature of the most interesting groups of Zn compounds.

The promise of marine molecules as cosmetic active ingredients

The marine environment represents an underexploited resource for the discovery of novel products, despite its high level of biological and chemical diversity. With increasing awareness of the harmful effects of chronic ultraviolet exposure, and a universal desire to improve cosmetic appearance, the market for new cosmetic ingredients is growing, and current trends have generated a greater demand for products sourced from the environment. A growing number of novel molecules from marine flora and fauna exhibit potent and effective dermatological activities. Secondary metabolites isolated from macroalgae, including carotenoids and polyphenols, have demonstrated antioxidant, anti-ageing and anti-inflammatory activities. In addition, marine extremophilic bacteria have recently been shown to produce bioactive exopolymeric molecules, some of which have been commercialized. Available data on their activities show significant antioxidant, moisturizing and anti-ageing activities, but a more focussed investigation into their mechanisms and applications is required. This review surveys the reported biological activities of an emerging and growing portfolio of marine molecules that show promise in the treatment of cosmetic skin problems including ultraviolet damage, ageing and cutaneous dryness.

Multiple microneedling sessions for minimally invasive facial rejuvenation: an objective assessment

BACKGROUND

Microneedling or percutaneous collagen induction is a new modality used for skin rejuvenation, tightening, and scar remodeling. It offers a simple and effective treatment for photoaged skin with minimal disruption of the epidermis, thus limiting adverse effects and minimizing downtime.

OBJECTIVES

To evaluate the efficacy, coupled with quantitative assessment, of the histological changes in response to multiple sessions of skin microneedling in the treatment of aging skin.

PATIENTS AND METHODS

Ten patients with Fitzpatrick skin type III and IV and Glogau class II to III wrinkles were subjected to six skin microneedling sessions at 2-week intervals. Standard photographs and skin biopsy specimens were obtained at baseline and at one and three months after the start of treatment. Histometry for epidermal thickness and quantitative evaluation of collagen types I, III, and VII, newly synthesized collagen, total elastin, and tropoelastin were performed for all skin biopsies.

RESULTS

Skin microneedling produced noticeable clinical improvement of photoaged skin, with corresponding histological enhancement. Compared to the baseline, collagen types I, III, and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase (P < 0.05) in response to treatment, while the mean level of total elastin was significantly decreased (P < 0.05) after treatment.

CONCLUSIONS

Skin microneedling is a promising minimally invasive treatment option with the advantage of increased collagen production. However, multiple sessions are usually needed to maintain the improvement achieved.

Zinc therapy in dermatology: a review

Zinc, both in elemental or in its salt forms, has been used as a therapeutic modality for centuries. Topical preparations like zinc oxide, calamine, or zinc pyrithione have been in use as photoprotecting, soothing agents or as active ingredient of antidandruff shampoos. Its use has expanded manifold over the years for a number of dermatological conditions including infections (leishmaniasis, warts), inflammatory dermatoses (acne vulgaris, rosacea), pigmentary disorders (melasma), and neoplasias (basal cell carcinoma). Although the role of oral zinc is well-established in human zinc deficiency syndromes including acrodermatitis enteropathica, it is only in recent years that importance of zinc as a micronutrient essential for infant growth and development has been recognized. The paper reviews various dermatological uses of zinc.

Repeated exposure of mouse dermal fibroblasts at a sub-cytotoxic dose of UVB leads to premature senescence: a robust model of cellular photoaging

BACKGROUND

Photoaging skin is due to accumulative effect of UV irradiation that mainly imposes its damage on dermal fibroblasts. To mimic the specific cellular responses invoked by long term effect of UVB, it is preferable to develop a photo-damaged model in vitro based on repeated UVB exposure instead of a single exposure.

OBJECTIVE

To develop a photo-damaged model of fibroblasts by repeated UVB exposure allowing for investigation of molecular mechanism underlying premature senescence and testing of potential anti-photoaging compounds.

METHODS

Mouse dermal fibroblasts (MDFs) at early passages (passages 1-3) were exposed to a series of 4 sub-cytotoxic dose of UVB. The senescent phenotypes were detected at 24 or 48h after the last irradiation including cell viability, ROS generation, mitochondrial membrane potential, cell cycle, production and degradation of extracellular matrix.

RESULTS

Repeated exposure of UVB resulted in remarkable features of senescence. It effectively avoided the disadvantages of single dose such as induction of cell death rather than senescence, inadequate stress resulting in cellular self-rehabilitation.

CONCLUSION

Our work confirms the possibility of detecting cellular machinery that mediates UVB damage to fibroblasts in vitro by repeated exposure, while the potential molecular mechanisms including cell surface receptors, protein kinase signal transduction pathways, and transcription factors remain to be further evaluated.

Efficacy of mesotherapy in facial rejuvenation: a histological and immunohistochemical evaluation

BACKGROUND

Mesotherapy, commonly known as "biorejuvenation" or "biorevitalization", is a technique used to rejuvenate the skin by means of a transdermal injection of a multivitamin solution and natural plant extracts that are thought to improve the signs of skin aging.

OBJECTIVES

This prospective study aimed to evaluate the clinical effect of mesotherapy applied to periorbital wrinkles and to quantitatively evaluate histological changes in the skin occurring in response to the same treatment.

METHODS

Six volunteers with Fitzpatrick skin types III or IV and Glogau class I-III wrinkles were subjected to a three-month course of mesotherapy injections in the periocular area (six sessions administered at two-week intervals). Standard photographs and skin biopsies were obtained from the treatment area at baseline, at the end of treatment, and at three months post-treatment. Quantitative evaluation of collagen types I, III, and VII, newly synthesized collagen, total elastin, and tropoelastin was performed using a computerized morphometric analysis.

RESULTS

The clinical evaluation of volunteers at baseline, end of treatment, and three months post-treatment revealed no significant differences. Histological and immunostaining analysis of collagen types I, III, and VII, newly synthesized collagen, total elastin, and tropoelastin showed no statistically significant changes (P > 0.05) after mesotherapy injection.

CONCLUSIONS

The present study indicates that mesotherapy for skin rejuvenation does not result in statistically significant histological changes or clinical improvement.

Multiple minimally invasive Erbium: Yttrium Aluminum Garnet laser mini-peels for skin rejuvenation: an objective assessment

BACKGROUND

As the demand for minimally invasive rejuvenation is increasing, micropeel resurfacing using Erbium:Yttrium Aluminum Garnet (Er:YAG) laser 2940 nm has been reported for the treatment of photoaged skin without ablation of the epidermis. However, little is known about the efficacy and underlying histologic changes associated with this type of treatment.

AIMS

The aims of this study are to evaluate the clinical effect and objectively quantify the histological changes in response to multiple sessions of Er:YAG laser 2940 nm mini-peels.

PATIENTS AND METHODS

Six female volunteers of Fitzpatrick skin type III-IV and Glogau's class I-III wrinkles were subjected to six microresurfacing peels at 2-week intervals using Er:YAG 2940 nm laser at subablative fluences of 2-3 J/cm(2) to treat periorbital rhytides. Quantitative evaluation of collagen types I, III, and VII, newly synthesized collagen, total elastin, and tropoelastin was performed by histochemistry and immunohistochemistry coupled with computerized morphometric analysis at base line, end of treatment, and 3 months post-treatment.

RESULTS

Compared to the base line, evaluation of volunteers revealed obvious clinical improvement in response to Er:YAG mini-peels. Collagen types I, III, and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase in response to treatment, while the mean level of total elastin was significantly decreased in response to treatment. However, this was followed by regression of improvement at 3 months post-treatment but was still better than baseline.

CONCLUSIONS

This study revealed that multiple Er:YAG mini-peels is a promising treatment option for photoaging as it reverses the signs of photoaged skin with little downtime and side effects. However, to maintain the short-term improvement achieved after treatment, continued Er:YAG 2940 nm laser mini-peels is required.

Fractional versus ablative erbium:yttrium-aluminum-garnet laser resurfacing for facial rejuvenation: an objective evaluation

BACKGROUND

Laser is one of the main tools for skin resurfacing. Erbium:yttrium-aluminum-garnet (Er:YAG) was the second ablative laser, after carbon dioxide, emitting wavelength of 2940 nm. Fractional laser resurfacing has been developed to overcome the drawbacks of ablative lasers.

OBJECTIVE

We aimed to objectively evaluate the histopathological and immunohistochemical effects of Er:YAG 2940-nm laser for facial rejuvenation (multiple sessions of fractional vs single session of ablative Er:YAG laser).

METHODS

Facial resurfacing with single-session ablative Er:YAG laser was performed on 6 volunteers. Another 6 were resurfaced using fractional Er:YAG laser (4 sessions). Histopathological (hematoxylin-eosin, orcein, Masson trichrome, and picrosirius red stains) and immunohistochemical assessment for skin biopsy specimens were done before laser resurfacing and after 1 and 6 months. Histometry for epidermal thickness and quantitative assessment for neocollagen formation; collagen I, III, and VII; elastin; and tropoelastin were done for all skin biopsy specimens.

RESULTS

Both lasers resulted in increased epidermal thickness. Dermal collagen showed increased neocollagen formation with increased concentration of collagen types I, III, and VII. Dermal elastic tissue studies revealed decreased elastin whereas tropoelastin concentration increased after laser resurfacing. Neither laser showed significant difference between their effects clinically and on dermal collagen. Changes in epidermal thickness, elastin, and tropoelastin were significantly more marked after ablative laser.

LIMITATIONS

The small number of patients is a limitation, yet the results show significant improvement.

CONCLUSION

Multiple sessions of fractional laser have comparable effects to a single session of ablative Er:YAG laser on dermal collagen but ablative laser has more effect on elastic tissue and epidermis.

Effects of PPAR-delta agonist and zinc on vaginal smooth muscle cells collagen and tropoelastin production

INTRODUCTION AND HYPOTHESIS

The objective was to measure the effects of peroxisome proliferator-activated receptor delta (PPAR-delta) agonist and zinc sulfate (ZS) on vaginal smooth muscle cell (SMC) proliferation, tropoelastin production, and collagen production.

METHODS

SMC cultures were performed from vaginal wall biopsies and were incubated with ZS and PPAR-delta agonist GW501516 (GW). Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Supernatants and cell lysates were collected. Tropoelastin production was measured by Fastin Elastin Assay and collagen was measured with Sircol Collagen Assay.

RESULTS

SMC proliferation was similar with 20 μM ZS or 10 nM GW compared to control. Tropoelastin production was significantly increased by 20 μM ZS and by 10 nM GW. Cell culture surface deposited elastin production was significantly increased by 20 μM ZS and by the combination of 20 μM ZS with 10 nM GW, and collagen production was significantly increased by 10 nM GW and by the combination of 20 μM ZS with 10 nM GW.

CONCLUSIONS

PPAR-delta agonist and ZS increases vaginal SMC tropoelastin and collagen production.

Non-invasive evaluation of dermal elastosis by in vivo multiphoton tomography with autofluorescence lifetime measurements

The non-invasive differentiation of dermal elastic fibres from solar elastosis in vivo is of great interest in dermatologic research, especially for efficacy testing of anti-ageing products. To date, no studies on multiphoton excited fluorescence lifetime characteristics of human elastic fibres and solar elastosis are reported. The goal of the present work was the identification of differential criteria for elastic fibres and solar elastosis by the analysis of fluorescence decay curves acquired by time-correlated single photon counting in vivo multiphoton tomography. For this purpose, fluorescence lifetime measurements (FLIM) were performed with 47 volunteers of different age groups at sun-protected and sun-exposed localizations. Bi-exponential curve fitting was applied to the FLIM data, and characteristic differences between age groups and localizations were found in both relevant fit parameters describing the decay slope. The FLIM analyses have shown that dermal autofluorescence has different lifetimes depending on age and in part on localization.

Effects of the Nd:YAG 1320-nm laser on skin rejuvenation: clinical and histological correlations

The neodymium:yttrium-aluminum-garnet (Nd:YAG) laser is a popular non-ablative treatment used for skin rejuvenation. The purpose of this prospective study was to evaluate the clinical effects, coupled with a quantitative assessment, of the histological changes in response to Nd:YAG 1320-nm laser treatment of periocular wrinkles. Six volunteers with Fitzpatrick skin types III and IV and Glogau class I-II wrinkles were subjected to 3 months of Nd:YAG 1320-nm treatment in the periocular area (six sessions at 2-week intervals). Volunteers were photographed, and skin biopsies were obtained at baseline as well as 3 and 6 months after the start of treatments. Quantitative evaluation of total elastin, newly synthesized tropoelastin, collagen types I, III and VII, and newly synthesized collagen was performed using a computerized morphometric analysis. A noticeable clinical and histological improvement was observed after Nd:YAG 1320-nm treatment. Collagen types I, III and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase in response to treatment, while the mean level of total elastin was significantly decreased after treatment. Our data suggest that Nd:YAG 1320 nm is an effective treatment for skin rejuvenation as it stimulates the repair processes, and reverses the clinical, as well as the histopathological, signs of skin aging.

Aldosterone and mineralocorticoid receptor antagonists modulate elastin and collagen deposition in human skin

We have shown that the steroid hormone aldosterone, recognized for its action on the kidney and the cardiovascular system, also modulates deposition of extracellular matrix in human skin. We have shown that treatment of primary cultures of normal skin fibroblasts with aldosterone (10 n-1 μM), in addition to stimulation of collagen type I expression, induces elastin gene expression and elastic fiber deposition. We have further shown that the elastogenic effect of aldosterone, which can be enhanced in the presence of mineralocorticoid receptor (MR) antagonists spironolactone and eplerenone, is executed in a MR-independent manner via amplification of IGF-I receptor-mediated signaling. Because aldosterone applied alone stimulates both collagen and elastin deposition in cultures of fibroblasts and in cultures of skin explants derived from dermal stretch marks, we postulate that this steroid should be used in the treatment of damaged skin that loses its volume and elasticity. Moreover, aldosterone applied in conjunction with spironolactone or eplerenone induces matrix remodeling and exclusively enhances elastogenesis in cultures of fibroblasts and explants derived from dermal scars and keloids. We therefore propose that intra-lesional injection of these factors should be considered in therapy for disfiguring dermal lesions and especially in prevention of their recurrence after surgical excision.