Tissue dermal equivalent – а cellular product based on human dermal keratinocytes and fibroblasts: the properties of equivalent components and perspectives of practical application

The nature and ways of isolation and cultivation in vitro of keratinocytes and fibroblasts, the main cellular components of skin to prepare a new biomedical product, tissue dermal equivalent were considered. The main attention was payed to optimization of upbuilding dermal cell biomass including selection of medium compositions and conditions of cultivation. The information was given on main parameters of cell cultures as proliferation activity, viability and phenotype of the cells. Genotoxicity of fibroblasts and biocompatibility of the cells with organic matrixes to find the optimal carrier for cellular elements of tissue dermal equivalent were studied. The composition, the process of preparation of tissue dermal equivalent and perspectives of its practical application were discussed.

Cyclic growth of dermal papilla and regeneration of follicular mesenchymal components during feather cycling

How dermis maintains tissue homeostasis in cyclic growth and wounding is a fundamental un-solved question. Here we study how dermal components of feather follicles undergo physiological (molting) and plucking injury-induced regeneration. Proliferation analyses reveal quiescent, transient-amplifying, and long-term label-retaining dermal cell (LRDC) states. In Growth phase, LRDCs are activated to make new dermal components with distinct cellular flows. Dermal transient amplifying (TA) cells, enriched in the proximal follicle, generate (i) peripheral pulp which extends distally to expand the epithelial-mesenchymal interactive interface for barb patterning, and (ii) central pulp which provides nutrition. Entering Resting phase, LRDCs, accompanying collar bulge epidermal LRC cells, descend to the apical dermal papilla. In the next cycle, these apical derma papilla LRDCs are re-activated to become new pulp progenitor TA cells. In growth phase, lower dermal sheath can generate dermal papilla and pulp. Transcriptome analyses identify marker genes and highlight molecular signaling associated with dermal specification. We compare cyclic topological changes with that of hair follicle, a convergently evolved follicle configuration. The work presents a model for analyzing homeostasis and tissue remodeling of mesenchymal progenitors.

Diversity in root apoplastic barrier deposition in salt treated wild and domesticated barley seedlings

Salt stress causes changes in root apoplastic barriers, such as the endodermis and the exodermis, and these changes are associated with variation in abiotic stress tolerance. We explored variation in root apoplastic barrier traits, O consumption and root and shoot Na and K content in a diverse collection of commercial and wild barley accessions subjected to non-saline (control) and saline treatments. Lignin and suberin deposition in endo- and exo-dermal cell walls varied between the accessions and in response to salt treatments. Twenty-two wild barley accessions formed an exodermis in response to salt treatments, whereas the commercial barley cultivar Barke did not develop an obvious exodermis. Accessions with pronounced root barrier deposition tended to have lower O consumption relative to the accessions with less obvious barriers. Treatment with abscisic acid enhanced suberisation and lead to a pronounced formation of an exodermis in wild barley accessions, whereas treatment with an ethylene precursor had no obvious effect on suberisation. Principal component analysis revealed associations between suberin deposition, root and shoot Na and K, and root respiration. The variation in root apoplastic barrier traits within the barley accessions represents a useful resource for future crop breeding to improve environmental stress tolerance.

Effects of Black Jade on Osteogenic Differentiation of Adipose Derived Stem Cells under Benzopyrene

Jade, a popular gemstone symbolizing beauty, grace, and longevity, is known to improve blood circulation; however, scientific research evidence is still lacking. The effect of black jade extract on the expression levels of apoptotic and osteogenic genes was validated using qPCR and flow cytometry. In combination with the use of a fluorescence microscope, osteogenic differentiation and the stained osteocytes count were analyzed. Under the pressure of benzo(a)pyrene, dermal cell apoptosis was accelerated and the osteogenic differentiation of adipose-derived stem cells (ASCs) was suppressed; but black jade extract counteracted the effects. Through an anti-apoptotic mechanism, the extract suppressed the expression of apoptotic proteins Bax and cytochrome C to 9 and 4.8 times, respectively, compared to that in dermal cells exposed to benzo(a)pyrene. During osteogenic differentiation of ASCs, the extract enhanced their differentiation despite being exposed to benzo(a)pyrene, and the relative levels of the osteoblast differentiation markers osteoponin, osteocalcin, and sclerostin were 1.87, 2.54, and 3.9 times higher, respectively, than those in the conditioned medium by benzo(a)pyrene. These effects of the extract indicate that black jade extract is very useful when applied as a functional biomaterial.

Cell shape anisotropy and motility constrain self-organised feather pattern fidelity in birds

SummaryCellular self-organisation can emerge from stochastic fluctuations in properties of a developing tissue1–3. This mechanism explains the production of various motifs seen in nature4–7. However, events channelling its outcomes such that patterns are produced with reproducible precision key to fitness remain unexplored. Here, we compared the dynamic emergence of feather primordia arrays in poultry, finch, emu, ostrich and penguin embryos and correlated inter-species differences in pattern fidelity to the amplitude of dermal cell anisotropy in the un-patterned tissue. Using live imaging and ex vivo perturbations in these species, we showed that cell anisotropy optimises cell motility for sharp and precisely located primordia formation, and thus, proper pattern geometry. These results evidence a mechanism through which collective cellular properties of a developmental pattern system ensure stability in its self-organisation and contribute to its evolution.

Evaluation of the effects of acepromazine and xylazineon viability in an equine dermal cell line

Xylazine and acepromazine are drugs used exclusively in veterinary medicine. Xylazineis used as a sedative, analgesic, and tranquilizer while acepromazine is used as a sedative, pre-anesthetic, and anesthetic adjuvant. In vitrodrug toxicity experimentation is essential to predict possible damage associated with treatment. This study was carried out to evaluate and compare the in vitroeffects of acepromazine and xylazine on cell viability. Equine Dermis cells lines were used to examine different drug concentrations (0.02 mg/mL, 0.01 mg/mL, 0.005 mg/mL and 0.0025 mg/mL). An MTT assay was carried out to reveal cell viability. Both tested drugs reduced the viability of ED cells at 0.02 and 0.01 mg/mL. At 0.005 mg/mL, only acepromazine presented an effect. These results corroborate previous studies with xylazine. On the other hand, this is thefirst report about acepromazine and cell viability. Previous studies suggest that the mechanisms involved in reducing cell viability are apoptosis for xylazine and the activation of the autophagic pathway for acepromazine. Both mechanisms have been seen in other drugs of the same classes. These findings reveal that both acepromazine and xylazine cause concentration-dependent cytotoxicity in vitro. Future experiments could further elucidate the mechanisms by which this effect happens and thus circumvent therisk of potential tissue damage in vivo.

Nutritional, Antioxidant, Antimicrobial, and Toxicological Profile of Two Innovative Types of Vegan, Sugar-Free Chocolate

Increased sugar consumption and unhealthy dietary patterns are key drivers of many preventable diseases that result in disability and death worldwide. However, health awareness has increased over the past decades creating a massive on-going demand for new low/non-caloric natural sweeteners that have a high potential and are safer for consumption than artificial ones. The current study aims to investigate the nutritional properties, in vitro toxicological profile, total/individual polyphenols content, and the antioxidant, anti-cariogenic, and antimicrobial activity of two newly obtained vegan and sugar-free chocolate (VHC1 and VHC2). The energy values for the two finished products were very similar, 408.04 kcal/100 g for VHC1 and 404.68 kcal/100 g for VHC2. Both products, VHC1 and VHC2 present strong antioxidant activities, whereas antimicrobial results show an increased activity for VHC1 compared to VHC2, because of a higher phenolic content. In vitro toxicological evaluation revealed that both samples present a safe toxicological profile, while VHC2 increased cellular turnover of dermal cell lines, highlighting its potential use in skin treatments. The current work underlines the potential use of these vegetal mixtures as sugar-free substitutes for conventional products, as nutraceuticals, as well as topic application in skin care due to antimicrobial and antioxidant effects.

Small Extracellular Vesicles from Human Fetal Dermal Cells and Their MicroRNA Cargo: KEGG Signaling Pathways Associated with Angiogenesis and Wound Healing

The use of cell secreted factors in clinical settings could be an alternative to conventional cell therapy, with the advantage of limiting concerns generally associated with traditional cell transplantation, such as tumorigenicity, immunoreactivity, and carrying of infections. Based on our published data, we predict a potential role for extracellular vesicles (EVs) in contributing to the proangiogenic activity of human fetal dermal cell secretome. Depletion of nanosized EVs from secretome significantly impaired its ability to induce formation of mesh-like structures in vitro. The isolated EVs were characterized for size and concentration by nanoparticle tracking analysis, and for protein markers (Rab5+, Alix+, CD63+, and calnexin-). The microRNA profile of EVs revealed 87 microRNAs significantly upregulated (≥15-fold increase) in fetal compared to adult dermal cell-derived EVs. Interestingly, these upregulated microRNAs included microRNAs with a validated role in angiogenesis according to literature. Moreover, the DIANA-TarBase v7.0 analysis confirmed enrichment in the KEGG signaling pathways associated with angiogenesis and wound healing, with the identification of putative target genes including thrombospondin 1. To validate the in silico data, EVs were also characterized for total protein contents. When tested in in vitro angiogenesis, fetal dermal cell-derived EVs were more effective than their adult counterpart in inducing formation of complete mesh-like structures. Furthermore, treatment of fibroblasts with fetal dermal-derived EVs determined a 4-fold increase of thrombospondin 1 protein amounts compared with the untreated fibroblasts. Finally, visualization of CSFE-labeled EVs in the cytosol of target cells suggested a successful uptake of these particles at 4-8 hours of incubation. We conclude that EVs are important contributors of the proangiogenic effect of fetal dermal cell secretome. Hence, EVs could also serve as vehicle for a successful delivery of microRNAs or other molecules of therapeutic interest to target cells.

Interplay between Cell-Surface Receptors and Extracellular Matrix in Skin

Skin consists of the epidermis and dermis, which are connected by a specialized basement membrane—the epidermal basement membrane. Both the epidermal basement membrane and the underlying interstitial extracellular matrix (ECM) created by dermal fibroblasts contain distinct network-forming macromolecules. These matrices play various roles in order to maintain skin homeostasis and integrity. Within this complex interplay of cells and matrices, cell surface receptors play essential roles not only for inside-out and outside-in signaling, but also for establishing mechanical and biochemical properties of skin. Already minor modulations of this multifactorial cross-talk can lead to severe and systemic diseases. In this review, major epidermal and dermal cell surface receptors will be addressed with respect to their interactions with matrix components as well as their roles in fibrotic, inflammatory or tumorigenic skin diseases.