Sensitive ex vivo human skin transdermal assay testing method with mass spectrometric analysis for cosmetics application.

BACKGROUND: Cosmetics manufacturers are focused on cosmetic delivery systems into the skin, but the level of diffusion of the systems in the skin tissues is not well understood. The current methods, such as Franz diffusion, assess analyte diffusion in the whole skin or artificial membranes, which has limitations for understanding skin delivery systems. AIMS: Our study aimed to create a transdermal delivery method which is based on dermal-epidermal separation of human skin, allowing us to assess each layer of skin separately for its efficacy. MATERIALS AND METHODS: During the experiment, resveratrol was used as the target analyte by applying it to the skin and then separating it into dermis and epidermis. Each layer is treated individually and subjected to a high-resolution mass spectrometry analysis to detect resveratrol levels. As a result, the efficiency of resveratrol diffusion in the dermal and epidermal layers of the skin can be evaluated. RESULTS: We found that resveratrol was detected in both the dermal and epidermal layers using our method. CONCLUSIONS: Hence, we developed a sensitive method for transdermal delivery testing that can be used to evaluate skin delivery systems for cosmetic or pharmaceutical purposes.

Static Magnetic Field Stimulation Enhances Oligodendrocyte Differentiation and Secretion of Neurotrophic Factors.

The cellular-level effects of low/high frequency oscillating magnetic field on excitable cells such as neurons are well established. In contrast, the effects of a homogeneous, static magnetic field (SMF) on Central Nervous System (CNS) glial cells are less investigated. Here, we have developed an in vitro SMF stimulation set-up to investigate the genomic effects of SMF exposure on oligodendrocyte differentiation and neurotrophic factors secretion. Human oligodendrocytes precursor cells (OPCs) were stimulated with moderate intensity SMF (0.3 T) for a period of two weeks (two hours/day). The differential gene expression of cell activity marker (c-fos), early OPC (Olig1, Olig2. Sox10), and mature oligodendrocyte markers (CNP, MBP) were quantified. The enhanced myelination capacity of the SMF stimulated oligodendrocytes was validated in a dorsal root ganglion microfluidics chamber platform. Additionally, the effects of SMF on the gene expression and secretion of neurotrophic factors- BDNF and NT3 was quantified. We also report that SMF stimulation increases the intracellular calcium influx in OPCs as well as the gene expression of L-type channel subunits-CaV1.2 and CaV1.3. Our findings emphasize the ability of glial cells such as OPCs to positively respond to moderate intensity SMF stimulation by exhibiting enhanced differentiation, functionality as well as neurotrophic factor release.

Grafts enriched with subamnion-cord-lining mesenchymal stem cell angiogenic spheroids induce post-ischemic myocardial revascularization and preserve cardiac function in failing rat hearts.

A crucial question in post-ischemic cell therapy refers to the ideal method of cell delivery to the heart. We hypothesized that epicardial implantation of subamnion-cord-lining mesenchymal stem cells (CL-MSC) angiogenic spheroids embedded within fibrin grafts (SASG) facilitates donor cell survival and enhances cardiac function in failing rat hearts. Furthermore, we compared the efficacy of this approach applied through two delivery methods. Spheroids made of 1.5×10(4) human CL-MSC coated with 2×10(3) human umbilical vein endothelial cells were self-assembled in hanging drops. SASG were constructed by embedding 150 spheroids in fibrin matrix. Except for untreated rats (MI, n=8), grafts were implanted 2 weeks after myocardial infarction upon confirmation of ensued heart failure through thoracotomy: SASG (n=8) and fibrin graft (FG, n=8); or video-assisted thoracoscopic surgery (VATS): SASG-VATS (n=8) and FG-VATS (n=7). In vivo CL-MSC survival was comparable between both SASG-treated groups throughout the study. SASG and SASG-VATS animals had decreased left ventricular end-diastolic pressure relative to untreated animals, and increased fractional shortening compared to MI and FG controls, 4 weeks after treatment. A 14.1% and 6.2% enhancement in ejection fraction from week 2 to 6 after injury was observed in SASG/SASG-VATS, paralleled by improvement in cardiac output. Treated hearts had smaller scar size, and more blood vessels than MI, while donor CL-MSC contributed to arteriogenesis within the graft and infarct areas. Taken together, our data suggest that SASG treatment has the potential to restore failing hearts by preserving cardiac function and inducing myocardial revascularization, while attenuating cardiac fibrosis. Furthermore, we introduce a method for minimally invasive in situ graft assembly.

Immunological properties of extraembryonic human mesenchymal stromal cells derived from gestational tissue.

Mesenchymal stromal cells (MSCs) have been isolated from many tissues, including gestational tissue. To date, a study comparing the properties and suitability of these cells in cell-based therapies is lacking. In this study, we compared the phenotype, proliferation rate, migration, immunogenicity, and immunomodulatory capabilities of human MSCs derived from umbilical cord lining (CL-MSCs), umbilical cord blood (CB-MSCs), placenta (P-MSCs), and Wharton's jelly (WJ-MSCs). Differences were noted in differentiation, proliferation, and migration, with CL-MSCs showing the highest proliferation and migration rates resulting in prolonged survival in immunodeficient mice. Moreover, CL-MSCs showed a prolongation in survival in xenogeneic BALB/c mice, which was attributed to their ability to dampen TH1 and TH2 responses. Weaker human cellular immune responses were detected against CL-MSCs and P-MSCs, which were correlated with their lower HLA I expression. Furthermore, HLA II was upregulated less substantially by CL-MSCs and CB-MSCs after IFN-γ stimulation. MSC types did not differ in indolamine 2,3-dioxygenase (IDO) expression after IFN-γ stimulation. Despite their lower IDO, HLA-G, and TGF-ß1 expression, only CL-MSCs were able to reduce the release of IFN-γ by lymphocytes in a mixed lymphocyte reaction. In summary, CL-MSCs showed the best characteristics for cell-based strategies, as they are hypo-immunogenic and show high proliferation and migration rates. In addition, these studies show for the first time that although immunomodulatory molecules HLA-G, HLA-E, and TGF-ß play an important role in MSC immune evasion, basal and induced HLA expression seems to be decisive in determining the immunogenicity of MSCs.

Cord lining-mesenchymal stem cells graft supplemented with an omental flap induces myocardial revascularization and ameliorates cardiac dysfunction in a rat model of chronic ischemic heart failure.

Myocardial restoration using tissue-engineered grafts to regenerate the ischemic myocardium offers improved donor cell retention, yet a limited cell survival resulting from poor vascularization needs to be addressed. A cell type derived from the subamnion, namely, cord-lining mesenchymal stem cells (CL-MSC), has recently been identified. Here we present a restorative strategy that combines a fibrin graft containing human CL-MSC and omental flap providing, thereby, cell-, structural-, and angiogenic support to the injured myocardium. The graft consisted of a mixture of 2×10(6) CL-MSC-GFP-Fluc and fibrin. Myocardial infarction (MI) was induced in nude rats and following confirmation of ensued heart failure with echocardiography 2 weeks after injury, therapeutic intervention was performed as follows: untreated (MI, n=7), CL-MSC graft (CL-MSCG, n=8), CL-MSCG and omental flap (CL-MSCG+OM, n=11), and omental flap (OM, n=8). In vivo bioluminescence imaging at 1, 3, 7, and 14 days post-treatment indicated comparable early donor cell viability between the CL-MSCG and CL-MSCG+OM. Treatment with CL-MSCG+OM improved the myocardial function as assessed by the measurement of end-diastolic left ventricular (LV) pressure (3.53±0.34 vs. 5.21±0.54 mmHg, p<0.05), contractility (+dP/dt, 3383.8±250.78 mmHg vs. 2464.9±191.8 mmHg, p<0.05), and the relaxation rate (-dP/dt, -2707.2±250.7 mmHg vs. 1948.7±207.8 mmHg, p<0.05), compared to MI control 6 weeks after ischemic injury. Furthermore, evidence of a 20.32% increase in the ejection fraction was observed in CL-MSCG+OM rats from week 2 to 6 after injury. Both CL-MSCG and CL-MSCG+OM led to an enhanced cardiac output (p<0.05), and attenuated the infarct size (35.7%±4.2% and 34.7%±4.8%), as compared to MI (60.7%±3.1%; p<0.01 and p<0.001, respectively). All treated groups had a higher arteriole density than controls. Yet, a higher amount of functional blood vessels, and a 20-fold increase in arteriole numbers were found in CL-MSCG+OM. Altogether, CL-MSCGs supplemented with vascular supply have the potential to repair the failing, chronically ischemic heart by improving myocardial revascularization, attenuating remodeling, and ameliorating cardiac dysfunction.

Immunogenicity and immunomodulatory properties of umbilical cord lining mesenchymal stem cells.

We here present an immunologic head-to-head comparison between human umbilical cord lining mesenchymal stem cells (clMSCs) and adult bone marrow MSCs (bmMSCs) from patients >65 years of age. clMSCs had significantly lower HLA class I expression, higher production of tolerogenic TGF-ß and IL-10, and showed significantly faster proliferation. In vitro activation of allogeneic lymphocytes and xenogeneic in vivo immune activation was significantly stronger with bmMSCs, whereas immune recognition of clMSCs was significantly weaker. Thus, bmMSCs were more quickly rejected in immunocompetent mice. IFN-γ at 25 ng/ml increased both immunogenicity by upregulation of HLA class I/ HLA-DR expression and tolerogenicity by increasing intracellular HLA-G and surface HLA-E expression, augmenting TGF-ß and IL-10 release, and inducing indoleamine 2,3-dioxygenase (IDO) expression. Higher concentrations of IFN-γ (>50 ng/ml) further enhanced the immunosuppressive phenotype of clMSCs, more strongly downregulating HLA-DR expression and further increasing IDO production (at 500 ng/ml). The net functional immunosuppressive efficacy of MSCs was tested in mixed lymphocyte cultures. Although both clMSCs and bmMSCs significantly reduced in vitro immune activation, clMSCs were significantly more effective than bmMSCs. The veto function of both MSC lines was enhanced in escalating IFN-γ environments. In conclusion, clMSCs show a more beneficial immunogeneic profile and stronger overall immunosuppressive potential than aged bmMSCs.

The role of hepatocyte growth factor/c-Met system in keloid pathogenesis.

BACKGROUND: Keloid scar is a fibroproliferative disorder characterized by increased deposition of extracellular matrix components. Hepatocyte growth factor (HGF), also known as the "scatter factor," and its receptor, a product of the Met oncogene, play multiple roles in regulating cell behavior. However, the role of this system in pathogenic fibrosis is still unclear. Our aim was to investigate and to clarify the role of HGF and its receptor c-Met in pathogenesis of keloid scars. METHODS: This study investigated the expression profile of HGF and c-Met in keloid and normal skin tissue. In addition, the role of normal and keloid keratinocytes in modulating the expression of fibroblast HGF (epithelial-mesenchymal interactions) was examined using a two-chamber serum-free coculture model. The effect of serum stimulation on fibroblast expression of HGF and c-Met was also studied. RESULTS: Increased levels of HGF and c-Met were observed in tissue extracts obtained from keloid tissue. Increased levels of HGF and c-Met localization were observed in the basal epidermis and in the dermis of keloid tissue compared with normal skin. Serum stimulation seemed to upregulate the expression of both HGF and c-Met in fibroblasts. Finally, coculture of keloid keratinocytes with keloid fibroblasts upregulated levels of both HGF and c-Met in keratinocyte cell lysates and conditioned media obtained from fibroblast culture. CONCLUSIONS: These findings emphasize the importance of the HGF/c-Met system in keloid biology and pathogenesis and suggest a possible target for therapeutic intervention in the prevention and treatment of keloids.

Syndecan-2 and decorin: proteoglycans with a difference--implications in keloid pathogenesis.

BACKGROUND: Growth factors and cytokines involved in the wound healing process seem to be immobilized at the cell surface and extracellular matrix via binding with proteoglycans, making them important modulators of cell dynamics. Our aim was to investigate the expression of two proteoglycans, namely syndecan-2 and decorin, and to elucidate their role in the pathogenesis of an aberrant wound healing process leading to keloid scar. METHODS: Intrinsic expression of syndecan-2, fibroblast growth factor (FGF)-2, and decorin in keloid tissue was investigated using Western blotting and immunohistochemistry. Normal and keloid fibroblasts were treated with serum to see the effects of serum growth factors on the expression of syndecan-2 and decorin. The role of epithelial-mesenchymal interactions in modulating syndecan-2, FGF-2, and decorin expression was investigated using an established two-chamber serum-free coculture model. Finally, the antifibrotic effect of decorin was investigated by studying its effect on the expression of extracellular matrix components. RESULTS: Syndecan-2 and FGF-2 were upregulated in keloid tissue; decorin was downregulated. Normal and keloid fibroblasts treated with serum led to increase in syndecan-2 and decrease in decorin expression. Under coculture conditions, syndecan-2 was shed in the conditioned media. FGF-2 was also upregulated under coculture conditions and, when added to fibroblast monocultures, increased shedding of syndecan-2. Decorin levels were upregulated under coculture conditions only in normal cocultures. Decorin was also able to decrease extracellular matrix proteins, highlighting its importance as an antifibrotic agent. CONCLUSION: Syndecan-2 and FGF-2 are not only overexpressed in keloid tissues but may interact with each other resulting in the shedding of syndecan-2, which in turn might activate a whole cascade of events responsible for a keloidic phenotype. In addition, decorin had an antifibrotic effect and could well be used as a potential therapeutic agent for keloids.

Isolation and characterization of mesenchymal stem cells from the sub-amniotic human umbilical cord lining membrane.

The use of human stem cells (SCs) is a promising novel approach for the treatment of many diseases and injuries. Umbilical cord and amniotic membrane represent good sources for SCs, because they are abundant sources and there are less ethical issues unlike embryonic SCs. We aimed to isolate and characterize adult SCs from the subamnion region of the umbilical cord/amniotic membrane. Because mesenchymal stem cells (MSCs) are thought to show less immunogenicity, we first focused on the characterization of MSCs. Significant expression of typical SC-specific markers, such as SSEA-4, Oct-4, and Nanog was observed. Subamniotic MSCs did not lose the expression of Oct-4 and Nanog after freeze-thawing. Cell surface expression of MSC markers (CD73 and CD105) was confirmed by flow cytometry, and cells also differentiated into adipogenic, osteogenic, and chondrogenic lineages. On the other hand, typical embryonic SC-specific markers were not expressed and the cells also did not grow in soft agar. Thus, the subamniotic MSCs are distinct from embryonic SCs and do not show tumorigenicity in vitro. The cord lining membrane (subamniotic) MSCs isolated by our method maintain typical characteristics of MSCs in vitro, but also showed several specific features.

The role of the activin system in keloid pathogenesis.

Keloid scars represent a pathological response to cutaneous injury under the regulation of many growth factors. Activin-A, a dimeric protein and a member of the transforming growth factor-beta superfamily, has been shown to regulate various aspects of cell growth and differentiation in the repair of the skin mesenchyme and the epidermis. Thus our aim was to study the role of activin and its antagonist, follistatin, in keloid pathogenesis. Increased mRNA expression for activin was observed in keloid scar tissue by performing RNase protection assay. Immunohistochemistry showed increased localization of both activin-A and follistatin in the basal layer of epidermis of keloid tissue compared with normal tissue. ELISA demonstrated a 29-fold increase in concentration of activin-A and an approximately 5-fold increase in follistatin in conditioned media in keloid fibroblasts compared with normal fibroblasts. Although keloid keratinocytes produced 25% more follistatin than normal keratinocytes, the amounts of activin-A, in contrast, was approximately 77% lower. Proliferation of fibroblasts was stimulated when treated with exogenous activin-A (46% increase in keloids fibroblasts) or following co-culture with hbetaAHaCaT cells (66% increase). Activin-A upregulated key extracellular matrix components, namely collagen, fibronectin, and alpha-smooth muscle actin, in normal and keloid fibroblasts. Co-treatment of follistatin with activin-A blocked the stimulatory effects of activin on extracellular matrix components. These findings emphasize the importance of the activin system in keloid biology and pathogenesis and suggest a possible therapeutic potential of follistatin in the prevention and treatment of keloids.