Whitening effects of adipose-derived stem cells: a preliminary in vivo study

Insights into the role of mesenchymal stem cells in cutaneous medical aesthetics: from basics to clinics

With the development of the economy and the increasing prevalence of skin problems, cutaneous medical aesthetics are gaining more and more attention. Skin disorders like poor wound healing, aging, and pigmentation have an impact not only on appearance but also on patients with physical and psychological issues, and even impose a significant financial burden on families and society. However, due to the complexities of its occurrence, present treatment options cannot produce optimal outcomes, indicating a dire need for new and effective treatments. Mesenchymal stem cells (MSCs) and their secretomics treatment is a new regenerative medicine therapy that promotes and regulates endogenous stem cell populations and/or replenishes cell pools to achieve tissue homeostasis and regeneration. It has demonstrated remarkable advantages in several skin-related in vivo and in vitro investigations, aiding in the improvement of skin conditions and the promotion of skin aesthetics. As a result, this review gives a complete description of recent scientific breakthroughs in MSCs for skin aesthetics and the limitations of their clinical applications, aiming to provide new ideas for future research and clinical transformation.

Therapeutic potential of adipose tissue-derivatives in modern dermatology

Stem cell-mediated therapies in combination with biomaterial and growth factor-based approaches in regenerative medicine are rapidly evolving with increasing application beyond the dermatologic field. Adipose-derived stem cells (ADSCs) are the more frequently used adult stem cells due to their abundance and easy access. In the case of volumetric defects, adipose tissue can take the shape of defects, restoring the volume and enhancing the regeneration of receiving tissue. When regenerative purposes prevail on volume restoration, the stromal vascular fraction (SVF) rich in staminal cells, purified mesenchymal stem cells (MSCs) or their cell-free derivatives grafting are favoured. The therapeutic efficacy of acellular approaches is explained by the fact that a significant part of the natural propensity of stem cells to repair damaged tissue is ascribable to their secretory activity that combines mitogenic factors, cytokines, chemokines and extracellular matrix components. Therefore, the secretome's ability to modulate multiple targets simultaneously demonstrated preclinical and clinical efficacy in reversing pathological mechanisms of complex conditions such atopic dermatitis (AD), vitiligo, psoriasis, acne and Lichen sclerosus (LS), non-resolving wounds and alopecia. This review analysing both in vivo and in vitro models gives an overview of the clinical relevance of adipose tissue-derivatives such as autologous fat graft, stromal vascular fraction, purified stem cells and secretome for skin disorders application. Finally, we highlighted the major disease-specific limitations and the future perspective in this field.

The dark side of adipose-derived mesenchymal stromal cells in cutaneous oncology: roles, expectations, and potential pitfalls

Adipose-derived stromal cells (ADSCs) have well-established regenerative and immunomodulatory properties. For such reasons, ADSCs are currently under investigation for their use in the setting of both regenerative medicine and autoimmune diseases. As per dermatological disorders, MSC-based strategies represent potential therapeutic tools not only for chronic ulcers and wound healing, but also for immune-mediated dermatoses. However, a growing body of research has been focusing on the role of MSCs in human cancers, due to the potential oncological risk of using MSC-based strategies linked to their anti-apoptotic, pro-angiogenic and immunosuppressive properties. In the dermatological setting, ADSCs have shown not only to promote melanoma growth and invasiveness, but also to induce drug-resistance. On the other hand, genetically modified ADSCs have been demonstrated to efficiently target therapies at tumor sites, due to their migratory properties and their peculiar tropism for cancer microenvironment. The present review briefly summarizes the findings published so far on the use of ADSCs in the dermato-oncological setting, with the majority of data being available for melanoma.

Exploring the Role and Mechanism of Adipose Derived Mesenchymal Stem Cells on Reversal of Pigmentation Model Effects

Interventions for extrinsic aging can be implemented, but these must address photoaging, which is the primary cause of extrinsic aging. Pigmentation due to photoaging depends on the duration and intensity of sun exposure. This study investigated the relationship between adipose-derived mesenchymal stem cells (ASCs) and photoaging pigmentation, and the underlying mechanism of action by establishing a photoaging pigmentation model using various treatments and exposure options in a guinea pigs. The energy dose of each UVB irradiation was 120 mJ/cm² and the total dose of irradiation was 360 mJ/cm². After successfully establishing the photoaging model, ASCs (1×10⁶) in an balanced salt solution (0.9 ml), balanced salt solution (0.9 ml), and bFGF (9 μg) mixed with an balanced salt solution (0.9 ml) were injected intradermally in ten guinea pigs. ELISA, macroscopic skin and histological observations, and Masson-Fontana staining were done. At 2 and 4 weeks post-injection, noticeable changes were observed. Guinea pigs receiving ASCs injections displayed significantly lower visible skin scores while the melanin content continued to decrease. Somewhat improved histopathological morphology, including epidermal thinning, dermal thickening, and little inflammatory cell infiltration was observed immediately after and up to 4 weeks of ASCs injection. Melanocortin 1 receptor (MC1R) and alpha-melanocyte test hormone (alpha-MSH) levels reduced significantly, and basic fibroblast growth factor (bFGF) levels increased significantly immediately after and up to 4 weeks of ASCs injection. The MC1R and alpha-MSH levels reduced significantly immediately after and up to 4 weeks of bFGF injection. Briefly, intradermal ASCs injection can notably eliminate pigmentation in a guinea pig photoaging pigmentation model. This may be related to the fact that bFGF secreted by ASCs lowers MC1R and alpha-MSH levels, blocks the cAMP signalling pathway, and inhibits melanin synthesis. This finding may present new options for treating photoaging pigmentation.Level of Evidence: N/A.

"Treatment of En Coup de Sabre Deformity with Fat Grafting and Demineralized Bone Matrix: A Case Series"

En coup de sabre deformity (ECDS) is a form of localized scleroderma in the frontoparietal region caused by progressive subcutaneous tissue atrophy and bony defect. Although ECDS involves two layers, skin/subcutaneous tissue and bone, the existing literature mainly focuses only on treating the skin/subcutaneous tissue layer. In this case series, we aimed to propose a novel approach that includes the combined use of fat grafting and demineralized bone matrix (DBM). Four patients with ECDS deformity, operated between February 2016 and October 2018, were retrospectively evaluated. All the patients were treated with the novel approach. Patients were evaluated with localized scleroderma scale and computed tomography (CT) scan in the preoperative period and at the annual follow-up. We observed remarkable improvement in the localized scleroderma scale including appearance, palpation, and size scores in all patients at the annual follow-up. CT scans at the annual follow-up revealed new callus formation at the bony defect area in all patients. Reinforcing fat grafting with DBM could promote healing of the bony and skin/subcutaneous tissue defects associated with ECDS.

Application of adipose-derived stem cells in photoaging: basic science and literature review

Photoaging is mainly induced by continuous exposure to sun light, causing multiple unwanted skin characters and accelerating skin aging. Adipose-derived stem cells(ADSCs) are promising in supporting skin repair because of their significant antioxidant capacity and strong proliferation, differentiation, and migration ability, as well as their enriched secretome containing various growth factors and cytokines. The identification of the mechanisms by which ADSCs perform these functions for photoaging has great potential to explore therapeutic applications and combat skin aging. We also review the basic mechanisms of UV-induced skin aging and recent improvement in pre-clinical applications of ADSCs associated with photoaging. Results showed that ADSCs are potential to address photoaging problem and might treat skin cancer. Compared with ADSCs alone, the secretome-based approaches and different preconditionings of ADSCs are more promising to overcome the current limitations and enhance the anti-photoaging capacity.

Effect of the Stromal Vascular Fraction on Changes in Melanin Formation in B16 Cells Treated by IBMX

OBJECTIVE

To investigate the effect of the stromal vascular fraction (SVF) on changes in melanin formation and tyrosinase activity in B16 cells treated by 3-isobutyl-1 methylxanthine (IBMX) and to explore the mechanism of SVF-mediated inhibition of pigmentation.

METHODS

We co-cultured extracted SVFs and B16 cells treated with IBMX in a certain proportion, and the marker molecule HMB-45 was detected by immunochemistry. Melanin content was determined by NaOH lysis. Activity of tyrosinase was measured by the DOPA oxidation method.

RESULTS

HMB-45 was commonly expressed in B16 cells induced by IBMX. After the addition of SVFs, the expression of HMB-45 decreased significantly and positively correlated with increases in SVFs. After the induction of B16 cells by IBMX, melanin content increased significantly. However, melanin decreased after SVF and B16 co-culturing; the effect was more substantial with the increase and decrease in SVFs, and the activity of tyrosinase decreased.

CONCLUSION

SVFs inhibit the production of melanin and reduce the activity of tyrosinase, possibly providing a new breakthrough for the treatment of pigment disorders.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Autologous chyle fat grafting for the treatment of hypertrophic scars and scar-related conditions

Background

Scarring is the product of natural restoration, yet its treatment remains challenging. Both collagen and fibroblasts are abnormally abundant in scars, leading to scar hyperplasia or contracture. Several clinical studies have reported that wrinkles at the recipient site are reduced, pores are narrowed, pigmentation is decreased, and skin is softened after autologous fat transplantation. In this study, we investigated the ability of autologous chyle fat injection to normalize the fibroblasts and collagen of scar tissue in 80 adult patients with hypertrophic scars resulting from severe burns received more than 1 year previously.

Methods

The patients underwent autologous chyle fat injection, and scar samples were collected at different time points. Differences in the number of adipocytes before and after chylosis were assessed by cell culture, and changes in the structural organization of the scars were detected via histologic and immunohistochemical analyses.

Results

After preparation, the chyle fat contained few autologous adipocytes and large amounts of extracellular matrix. Following the injection of chyle fat, the thickness, color, and elasticity of hypertrophic scar tissue tended toward normalization, and patient satisfaction increased. The three adipose tissue donor sites used for the preparation of chyle fat were the abdomen, buttocks, and inner thigh, of which the inner thigh yielded the best therapeutic outcomes. The density and quantity of fibroblasts in the scars decreased following the injection of chyle fat, and the arrangement, quantity, and shape of type III collagen fibers tended toward normalization. After three treatments, the results of immunohistochemical staining showed that type III collagen was significantly less abundant than before treatment.

Conclusions

Autologous chyle fat transplantation has a good therapeutic effect on hypertrophic scar tissue. The injection of chyle fat into hypertrophic scar tissue reduced the density and quantity of fibroblasts and prompted the arrangement, quantity, and shape of type III collagen to normalize.

Adipose Stem Cells with Conditioned Media for Treatment of Acne Vulgaris Scar

This study was to investigate the effect of subcutaneous injection of the adipose stem cells (ASCs) with conditioned media (CM) in the treatment of acne vulgaris scar. We used Adult male New Zealand white rabbit ears as an animal model and induced acne formation by Kignman method. Adipose tissue was isolated and harvested from the scapula of rabbits, and ASCs were cultured and expanded until passage 1. There have four groups in our experiment, include phosphate buffered saline (PBS), ASCs with PBS (ASC + PBS), CM, and ASCs with CM (ASC + CM) group. This solution of 0.6 ml injected to subcutaneous in each group. ASC + PBS and ASC + CM groups were containing ASCs of 5.0 × 106 cells/ml. We analyzed the treatment of 4 groups to scar tissue after 2 and 4 weeks by hematoxylin and eosin stain, immunohistochemistry, and RNA expression level of tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), and matrix metalloproteinase-2 (MMP-2). Also, the expression of keratin 16 (K16) was detected by western blot analysis. H&E stain showed that infiltration of inflammation cells was significantly reduced at 2 and 4 weeks, as well as re-epithelialization was improved in the ASC + CM group. The ASC + CM gourp was reduced both expression levels of TNF-α, IL-1α, and MMP-2 and K16 protein level. In conclusion, the ASCs with CM has a significant curative effect on acne vulgaris scar, more to the point, the CM has a key role on treatment. It could be applied to a therapeutic approach to regenerate to treat acne vulgaris scar.

The use of stem cells in aesthetic dermatology and plastic surgery procedures. A compact review of experimental and clinical applications

The aim of this paper was to collect currently available data related to the use of stem cells in aesthetic dermatology and plastic surgery based on a systemic review of experimental and clinical applications. We found that the use of stem cells is very promising but the current state of art is still not effective. This situation is connected with not fully known mechanisms of cell interactions, possible risks and side effects. We think that there is a big need to create and conduct different studies which could resolve problems of stem cells use for implementation into aesthetic dermatology and plastic surgery.

Efficacy of protein extracts from medium of Adipose-derived stem cells via microneedles on Asian skin

OBJECTIVES

To explore efficacy of protein extracts from medium of Adipose-derived stem cells (ADSCs) via microneedles on Asian skin in a double-blind, split-face, randomized, control study.

METHODS

Thirty volunteers received the treatment, left-side and right-side of their face were randomly assigned to test side and control side. The protein extracts from medium of ADSCs were applied via microneedles into the test side and ultrapure water was applied into the control side. The only person who knew what was being used by each subject on each side of the face was the therapist. Clinical evaluation including instrument test and self-questionnaire was performed by independent observers before and after the treatment, which lasted for 3 months.

RESULTS

All subjects completed the study. Compared to ultrapure water, the protein extracts from medium of ADSCs showed a statistically significant improvement for melanin index, skin brightness, gloss, skin roughness, elasticity, and wrinkles (p < 0.05). More than 70% of the participants described that all wrinkles, firmness, elasticity, hydration, whitening, and radiance were strongly improved in the test side.

CONCLUSIONS

Protein extracts from medium of ADSCs presented anti-aging and whitening efficacy via microneedles on Asian skin without skin adverse side.

Dermal Adipocytes: From Irrelevance to Metabolic Targets?

Dermal white adipose tissue (dWAT) has received little appreciation in the past as a distinct entity from the better recognized subcutaneous white adipose tissue (sWAT). However, recent work has established dWAT as an important contributor to a multitude of processes, including immune response, wound healing and scarring, hair follicle (HF) growth, and thermoregulation. Unique metabolic contributions have also been attributed to dWAT, at least in part due to its thermic insulation properties and response to cold exposure. Dermal adipocytes can also undergo an adipocyte-myofibroblast transition (AMT), a process that is suspected to have an important role in several pathophysiological processes within the skin. Here, we discuss emerging concepts regarding dWAT physiology and its significance to a variety of cellular processes.

Intralesional injection of adipose-derived stem cells reduces hypertrophic scarring in a rabbit ear model

INTRODUCTION

Redundant collagen deposition at sites of healing dermal wounds results in hypertrophic scars. Adipose-derived stem cells (ADSCs) exhibit promise in a variety of anti-fibrosis applications by attenuating collagen deposition. The objective of this study was to explore the influence of an intralesional injection of ADSCs on hypertrophic scar formation by using an established rabbit ear model.

METHODS

Twelve New Zealand albino rabbits were equally divided into three groups, and six identical punch defects were made on each ear. On postoperative day 14 when all wounds were completely re-epithelialized, the first group received an intralesional injection of ADSCs on their right ears and Dulbecco's modified Eagle's medium (DMEM) on their left ears as an internal control. Rabbits in the second group were injected with conditioned medium of the ADSCs (ADSCs-CM) on their right ears and DMEM on their left ears as an internal control. Right ears of the third group remained untreated, and left ears received DMEM. We quantified scar hypertrophy by measuring the scar elevation index (SEI) on postoperative days 14, 21, 28, and 35 with ultrasonography. Wounds were harvested 35 days later for histomorphometric and gene expression analysis.

RESULTS

Intralesional injections of ADSCs or ADSCs-CM both led to scars with a far more normal appearance and significantly decreased SEI (44.04 % and 32.48 %, respectively, both P <0.01) in the rabbit ears compared with their internal controls. Furthermore, we confirmed that collagen was organized more regularly and that there was a decreased expression of alpha-smooth muscle actin (α-SMA) and collagen type Ι in the ADSC- and ADSCs-CM-injected scars according to histomorphometric and real-time quantitative polymerase chain reaction analysis. There was no difference between DMEM-injected and untreated scars.

CONCLUSIONS

An intralesional injection of ADSCs reduces the formation of rabbit ear hypertrophic scars by decreasing the α-SMA and collagen type Ι gene expression and ameliorating collagen deposition and this may result in an effective and innovative anti-scarring therapy.

Adipose-derived stem cells inhibit epidermal melanocytes through an interleukin-6-mediated mechanism

BACKGROUND

Several investigators have postulated that human adipose-derived stem cells can be used for skin rejuvenation, but there have been few reports about their direct effects on human epidermal melanocytes. The authors studied the effects on melanocytes, and the causative agent of those effects was further investigated in this study.

METHODS

Human epidermal melanocytes were divided into three groups and cultured in adipose-derived stem cell-conditioned medium, human dermal fibroblast-conditioned medium, or control medium. Concentrations of melanogenic cytokines in these media were measured using enzyme-linked immunosorbent assay kits. After 3 and 7 days of incubation, cell proliferation, melanin content, tyrosinase activity, and melanogenic gene expression were measured. Interleukin-6-neutralizing antibodies were mixed with adipose-derived stem cell-conditioned medium in which human epidermal melanocytes were cultured, and melanocyte growth and melanogenesis were measured again.

RESULTS

Interleukin-6 concentrations in adipose-derived stem cell- and human epidermal melanocyte-conditioned media were 1373 and 495 pg/ml, respectively. Both types of medium suppressed melanocyte proliferation and melanin synthesis (p < 0.05), but adipose-derived stem cell-conditioned medium was more effective than human dermal fibroblast-conditioned medium in inhibition of human epidermal melanocyte proliferation, melanin synthesis, and tyrosinase activity (p < 0.05). Interleukin-6-neutralizing antibody sufficiently reversed the antimelanogenic effects of adipose-derived stem cell-conditioned medium such that human epidermal melanocyte proliferation, melanin content, tyrosinase activity, and tyrosinase mRNA levels were restored (p < 0.05).

CONCLUSIONS

Adipose-derived stem cell-conditioned medium inhibited melanocyte proliferation and melanin synthesis by down-regulating melanogenic enzymes. Interleukin-6 plays a pivotal role in inhibition of melanocytes.

The effect of conditioned media of adipose-derived stem cells on wound healing after ablative fractional carbon dioxide laser resurfacing

Objective. To evaluate the benefits of conditioned medium of Adipose-derived stem cells (ADSC-CM) on wound healing after fractional carbon dioxide laser resurfacing (FxCR) on human skin. Materials and Methods. Nineteen subjects were treated with FxCR on the bilateral inner arms. ADSC-CM was applied on FxCR site of one randomly selected arm. Transepidermal water loss (TEWL), skin color, and gross-elasticity of FxCR site on both arms were measured. Skin samples were taken by biopsy from three subjects 3 weeks after treatment for histopathological manifestations and mRNA expressions of procollagen types I and III, elastin genes were noted. Results. The index of erythema, melanin, and TEWL of the ADSC-CM-treated skin were significantly lower than those of the control side. The mRNA expression of type III procollagen in ADSC-CM-treated group at 3 weeks posttreatment was 2.6 times of that of the control group. Conclusion. Application of allograft ADSC-CM is an effective method for enhancing wound healing after FxCR, by reducing transient adverse effects such as erythema, hyperpigmentation, and increased TEWL.