Migration Of Human Dermal Fibroblasts Research Articles

Pristine Gellan Gum-Collagen Interpenetrating Network Hydrogels as Mechanically Enhanced Anti-inflammatory Biologic Wound Dressings for Burn Wound Therapy.

Gellan gum is a biologically inert natural polymer that is increasingly favored as a material-of-choice to form biorelevant hydrogels. However, as a burn wound dressing, native gellan gum hydrogels do not drive host's biology toward regeneration and are mechanically inadequate wound barriers. To overcome these issues, we fabricateda gellan gum-collagen full interpenetrating network (full-IPN) hydrogel that can house adipose-derived mesenchymal stem cells (ADSCs) and employ their multilineage differentiation potential and produce wound-healing paracrine factors to reduce inflammation and promote burn wound regeneration. Herein, a robust temperature-dependent simultaneous IPN (SIN) hydrogel fabrication process was demonstrated using applied rheology for the first time. Subsequently after fabrication, mechanical characterization assays showed that the IPN hydrogels were easy to handle without deforming and retained sufficient mass to effect ADSCs' anti-inflammation property in a simulated wound environment. The IPN hydrogels' increased stiffness proved conducive for mechanotransduced cell adhesion. Scanning electron microscopy revealed theIPN's porous network, which enabled encapsulated ADSCs to spread and proliferate, for up to 3 weeks of culture, further shown by cells' dynamic filopodia extension observed in 3D confocal images. Successful incorporation of ADSCs accorded the IPN hydrogels with biologic wound-dressing properties, which possess the ability to promote human dermal fibroblast migration and secrete an anti-inflammatory paracrine factor, TSG-6 protein, as demonstrated in the 2D scratch wound assay and ELISA, respectively. More importantly, upon application onto murine full thickness burn wounds, our biologic wound dressing enhanced early wound closure, reduced inflammation, and promoted complete skin regeneration. Altogether, our results highlight the successful mechanical and biological enhancement of the inert matrix of gellan gum. Through completely natural procedures, a highly applicable biologic wound dressing is introduced for cell-based full thickness burn wound therapy.

Blockade of LINC01605-enriched exosome generation in M2 macrophages impairs M2 macrophage-induced proliferation, migration, and invasion of human dermal fibroblasts.

Activated M2 macrophages are involved in hypertrophic scar (HS) formation via manipulating the differentiation of fibroblasts to myofibroblasts having the proliferative capacity and biological function. However, the function of exosomes derived from M2 macrophages in HS formation is unclear. Thus, this study aims to investigate the role of exosomes derived by M2 in the formation of HS. To understand the effect of exosomes derived from M2 macrophages on formation of HS, M2 macrophages were co-cultured with human dermal fibroblast (HDF) cells. Cell Counting Kit-8 assay was performed to evaluate HDF proliferation. To evaluate the migration and invasion of HDFs, wound-healing and transwell invasion assays were performed, respectively. To investigate the interaction between LINC01605 and miR-493-3p, a dual-luciferase reporter gene assay was adopted; consequently, an interaction between miR-493-3p and AKT1 was detected. Our results demonstrated that exosomes derived from M2 macrophages promoted the proliferation, migration, and invasion of HDFs. Additionally, we found that long noncoding RNA LINC01605, enriched in exosomes derived from M2 macrophages, promoted fibrosis of HDFs and that GW4869, an inhibitor of exosomes, could revert this effect. Mechanistically, LINC01605 promoted fibrosis of HDFs by directly inhibiting the secretion of miR-493-3p, and miR-493-3p down-regulated the expression of AKT1. Exosomes derived from M2 macrophages promote the proliferation and migration of HDFs by transmitting LINC01605, which may activate the AKT signaling pathway by sponging miR-493-3p. Our results provide a novel approach and basis for further investigation of the function of M2 macrophages in HS formation.

The Paracrine Effect of Adipose-Derived Stem Cells Orchestrates Competition between Different Damaged Dermal Fibroblasts to Repair UVB-Induced Skin Aging.

Background Human dermal fibroblasts (HDFs) are the primary cells in skin and are associated with UVB-induced skin photoaging. Adipose-derived stem cells (ASCs) have been proposed as a treatment for skin aging. The goal of this study was to investigate paracrine mechanisms by which ASCs repair HDFs damage from UVB exposure. Methods ASCs were cocultured with UVB-irradiated and nonirradiated HDFs. We compared HDF senescence, proliferation, migration, oxidative stress, and cytokine expression. In a nude mouse UVB-induced photoaging model, ASCs were injected subcutaneously, and skin samples were collected weekly between postoperative weeks 3 through 7. Histological analysis, PCR, ELISA, and immunohistochemistry were used to analyze the effect of ASCs. Results Compared with UVB-irradiated HDFs, nonirradiated HDFs showed higher proliferation and migration, reduced apoptosis, and fewer senescent cells when cocultured with ASCs. The expression of extracellular matrix-related cytokines was also regulated by ASCs. In addition, ASCs effectively reversed UVB-induced skin photoaging in vivo. We propose that ASCs more robustly coordinate healthy HDFs than UVB-damaged HDFs to repair aging skin. Conclusions ASCs improved the function of both UVB-damaged and healthy HDFs through paracrine effects. However, the impact of ASCs on healthy HDFs was greater than UVB-damaged HDFs. These findings help to elucidate the underlying mechanisms of the skin rejuvenation effect of ASCs.

Erythroid differentiation regulator 1 promotes wound healing by inducing the production of C‑C motif chemokine ligand2 via the activation of MAP kinases invitro and invivo.

The erythroid differentiation regulator 1 (Erdr1) protein has been studied for its role in various inflammatory skin diseases, including skin cancer, actinic keratosis and psoriasis. However, the therapeutic effects of Erdr1 on wound repair and its underlying mechanisms remain unknown. The present study aimed to investigate the effects of Erdr1 on wound healing in vitro and in vivo. The results demonstrated that treatment with recombinant Erdr1 enhanced wound healing in vivo and in vitro. In addition, Erdr1 increased the proliferation and migration of human dermal fibroblasts (HDFs). Notably, Erdr1 significantly induced the production of the chemoattractant C-C motif chemokine ligand 2 (CCL2) and recruited immune cells involved in wound healing. Treatment with recombinant Erdr1 induced the activation of the ERK1/1, p38 and JNK1/2 mitogen-activated protein (MAP) kinases. Treatment with specific inhibitors for MAP kinase inhibitors markedly suppressed cell proliferation and migration, and inhibited the production of CCL2 in HDFs. Furthermore, the inhibition of CCL2 with a neutralizing antibody significantly suppressed the recombinant Erdr1-induced proliferation and migration of HDFs. The wound healing activity of Erdr1 was comparable to that of epidermal growth factor. Taken together, these results demonstrated that Erdr1 promoted the proliferation and migration of HDFs and exhibited potent wound healing properties mediated by CCL2. Therefore, the results of the present study suggested that Erdr1 may be a potential therapeutic target for promoting wound healing.

In vitro antibacterial activity of extracts from Samoan medicinal plants and their effect on proliferation and migration of human fibroblasts

Ethnopharmacological relevanceThe prevalence of different types of chronic wounds, due to the ageing population and increase incidence of diseases, is becoming a worldwide problem. Various medicinal plants used in folk medicine have demonstrated wound healing and antimicrobial properties, and some of these species are currently used in commercial preparations. Despite the well-documented and rich tradition of the use of local herbs for the treatment of skin injuries in Samoan folk medicine, their wound healing potential has not yet been systematically studied. Aim of the studyInvestigation into the in vitro antibacterial activity of ethanol extracts from 14 medicinal plants used in Samoan traditional medicine for the healing of wounds, burns and sores, and their effects on the proliferation and migration of human fibroblasts. Materials and methodsThe antibacterial activity of these extracts was tested against pathogens associated with infected skin injuries, using the broth microdilution method. The effect on migration, proliferation and viability of human dermal fibroblasts was evaluated using wound healing scratch assay, cell proliferation assay, and thiazolyl blue tetrazolium bromide cytotoxicity test. ResultsThe extracts from Cerbera manghas, Commelina diffusa, Kleinhovia hospita, Mikania micrantha, Omalanthus nutans, Peperomia pellucida, Phymatosorus scolopendria, Piper graeffei, Psychotria insularum, and Schizostachyum glaucifolium inhibited the growth of Staphylococcus aureus at the minimum inhibitory concentration (MIC) of ≥4 μg/mL, whereas C. manghas and P. pellucida produced the same MIC against both Escherichia coli and Pseudomonas aeruginosa. Among the antibacterially active species, C. diffusa, K. hospita, P. scolopendria, P. insularum, and S. glaucifolium did not produce toxicity towards the standard line of normal adult human dermal fibroblasts (IC80 > 128 μg/mL). In addition, extracts from Barringtonia asiatica, C. manghas, M. micrantha, O. nutans, P. insularum, and Piper graeffei stimulated significant migration of dermal fibroblasts, while M. micrantha, O. nutans, and P. insularum did not affect cell proliferation at a concentration of 32 μg/mL. ConclusionsThe results suggest that the above-mentioned species of Samoan medicinal plants can be used for the development of new wound healing agents. However, further phytochemical and pharmacological research is needed regarding the isolation and identification of their active constituents.

Involvement of the lipoprotein receptor LRP1 in AMP-IBP5-mediated migration and proliferation of human keratinocytes and fibroblasts

BackgroundAntimicrobial peptide derived from insulin-like growth factor binding protein-5 (AMP-IBP5) is a potent antimicrobial agent that possesses various immunomodulatory activities. The parent protein of AMP-IBP5, IGFBP-5, has been shown to exert its effects via an insulin-like growth factor-1 receptor-independent mechanism, including binding to multifunctional low-density lipoprotein receptor-related protein 1 (LRP1), which contributes to several biological processes involved in skin wound healing. ObjectivesTo investigate whether LRP1 is involved in AMP-IBP5-induced migration and proliferation of human epidermal keratinocytes and dermal fibroblasts. MethodsThe mRNA expression of LRP1 and IGFBP-5 was assessed by quantitative real-time PCR, whereas Western blotting was used to evaluate the protein expression. Production of cytokines was determined by ELISA. Cell migration was measured by the scratch wound assay, whereas cell proliferation was analyzed using the BrdU labeling assay. MAPK activation was determined by Western blotting. ResultsWe found that AMP-IBP5 markedly induced the migration and proliferation of keratinocytes and fibroblasts, and this effect was reversed by specific siRNA and neutralizing antibody targeting the LRP1 receptor. In addition, LRP1 was upregulated by lipopolysaccharide, flagellin and AMP-IBP5 in keratinocytes and fibroblasts. LRP1 knockdown also inhibited MAPK pathway activation, which was required for AMP-IBP5-mediated cell migration and proliferation, as evidenced by the specific inhibitors for extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38. ConclusionsOur results suggest that LRP1 expressed in human epidermal keratinocytes and dermal fibroblasts contributes to AMP-IBP5-mediated cell migration and proliferation, supporting its crucial role in cutaneous wound healing process.

Potential Mechanism of Dermal Wound Treatment With Preparations From the Skin Gel of Arabian Gulf Catfish: A Unique Furan Fatty Acid (F6) and Cholesta-3,5-Diene (S5) Recruit Neutrophils and Fibroblasts to Promote Wound Healing.

Preparations from Arabian Gulf catfish (Arius bilineatus, Val) epidermal gel secretion (PCEGS) effectively heal chronic wounds in diabetic patients. However, specific lipid components of PCEGS that are responsible for various aspects of wound healing are unknown. Here, we report for the first time that, i) a unique preparation containing only proteins and lipids (Fraction B, FB), derived from the PCEGS accelerated the healing of experimental dermal wounds in female rats (transdermal punch biopsy) in vivo. Histological analyses showed that topical treatment of these wounds with FB promoted the migration of fibroblasts, facilitated the production of extracellular matrix (collagen, fibronectin), induced capillary formation and recruitment of immune cells, and accelerated overall wound healing by day 4 (tested at 1, 2, 3, 4, and 10 days; n=15 for vehicle; n=15 for FB treatment), ii) the lipids responsible for different stages of wound healing were separated into a protein-free bioactive lipid fraction, Ft, which contained a few common long-chain fatty acids, a unique furan fatty acid (F6) and a cholesterol metabolite, cholesta-3,5-diene (S5). Ft (the partially purified lipid fraction of PCEGS), and F6 and S5 present in Ft, proved to be bioactive for wound healing in human dermal fibroblasts. Ft increased the production and extracellular deposition of collagen and fibronectin, ex vivo, iii) Ft and its subcomponents, pure F6 and S5, also promoted human dermal fibroblast migration into the scratch wound gaps, ex vivo, iv) Ft, F6, and S5 promoted the recruitment of neutrophils (Green fluorescence protein labeled) to the site of injury in the transected tailfins of transgenic zebrafish, in vivo, v) Ft, but not F6 or S5, promoted the regeneration of tissues at the wound site in the transgenic zebrafish tailfin, in vivo. Therefore, we conclude that lipid fraction Ft from PCEGS contains the components necessary to promote complete wound healing, and F6 and S5 are responsible for promoting fibroblast and neutrophil recruitment to the site of wounds.

Neonatal Fibrin Scaffolds Promote Enhanced Cell Adhesion, Migration, and Wound Healing In Vivo Compared to Adult Fibrin Scaffolds.

Fibrin scaffolds are often utilized to treat chronic wounds. The monomer fibrinogen used to create such scaffolds is typically derived from adult human or porcine plasma. However, our previous studies have identified extensive differences in fibrin network properties between adults and neonates, including higher fiber alignment in neonatal networks. Wound healing outcomes have been linked to fibrin matrix structure, including fiber alignment, which can affect the binding and migration of cells. We hypothesized that fibrin scaffolds derived from neonatal fibrin would enhance wound healing outcomes compared to adult fibrin scaffolds. Fibrin scaffolds were formed from purified adult or neonatal fibrinogen and thrombin then structural analysis was conducted via confocal microscopy. Human neonatal dermal fibroblast attachment, migration, and morphology on fibrin scaffolds were assessed. A murine full thickness injury model was used to compare healing in vivo in the presence of neonatal fibrin, adult fibrin, or saline. Distinct fibrin architectures were observed between adult and neonatal scaffolds. Significantly higher fibroblast attachment and migration was observed on neonatal scaffolds compared to adults. Cell morphology on neonatal scaffolds exhibited higher spreading compared to adult scaffolds. In vivo significantly smaller wound areas and greater epidermal thickness were observed when wounds were treated with neonatal fibrin compared to adult fibrin or a saline control. Distinctions in neonatal and adult fibrin scaffold properties influence cellular behavior and wound healing. These studies indicate that fibrin scaffolds sourced from neonatal plasma could improve healing outcomes compared to scaffolds sourced from adult plasma.

Electroporation does not affect human dermal fibroblast proliferation and migration properties directly but indirectly via the secretome

Aesthetic wound healing is often experienced by patients after electrochemotherapy. We hypothesized that pulsed electric fields applied during electrochemotherapy (ECT) or gene electrotransfer (GET) protocols could stimulate proliferation and migration of human cutaneous cells, as described in protocols for electrostimulation of wound healing. We used videomicroscopy to monitor and quantify in real time primary human dermal fibroblast behavior when exposed in vitro to ECT and GET electric parameters, in terms of survival, proliferation and migration in a calibrated scratch wound assay. Distinct electric field intensities were applied to allow gradient in cell electropermeabilization while maintaining reversible permeabilization conditions, in order to mimic in vivo heterogeneous electric field distribution of complex tissues. Neither galvanotaxis nor statistical modification of fibroblast migration were observed in a calibrated scratch wound assay after application of ECT and GET parameters. The only effect on proliferation was observed under the strongest GET conditions, which drastically reduced the number of fibroblasts through induction of mitochondrial stress and apoptosis. Finally, we found that 24 h-conditioned cell culture medium by electrically stressed fibroblasts tended to increase the migration properties of cells that were not exposed to electric field. RT-qPCR array indicated that several growth factor transcripts were strongly modified after electroporation.

Mechanism of transcriptional regulation of Meox1 by transforming growth factor β (1) and its effect on cell migration of adult human dermal fibroblasts

Objective: To explore the transcriptional regulation mechanism of transforming growth factor β(1) (TGF-β(1)) on Meox1 and its effect on cell migration of adult human dermal fibroblasts (HDF-a). Methods: (1) HDF-a cells were cultured in RPMI 1640 complete medium (hereinafter referred to as routinely cultured). The cells were divided into TGF-β(1) stimulation group and blank control group. The cells in TGF-β(1) stimulation group were stimulated with 10 μL TGF-β(1) in the mass concentration of 1 mg/μL, while the cells in blank control group were stimulated with the equal volume of phosphate buffer solution. After 72 hours in culture, partial cells in both groups were collected for transcriptome sequencing. The genes with differential expression ratio greater than or equal to 2 and P 0.05); the enrichment of Smad4 protein on the promoter of Meox1 in the cells of empty plasmid group was similar to that of Smad4 OE group (t=0.60, P>0.05). (5) Twenty-four hours after scratching, the scratch healing width of cells in siRNA-Meox1 group was narrower than that of negative interference group, while that of Meox1 OE group was wider than that of empty plasmid group. After 24 hours in culture, the number of migration cells in negative interference group was significantly higher than that in siRNA-Meox1 group (t=9.12, P<0.01), and that in empty plasmid group was significantly lower than that in Meox1 OE group (t=8.99, P<0.01). (6) The expression of Meox1 protein in the scar tissue was significantly higher than that in normal skin of patients with hypertrophic scars. Conclusions: TGF-β(1) transcriptionally regulates Meox1 expression via Smad2/3 in HDF-a cells, thus promoting cell migration.

Skin Microcolumns as a Source of Paracrine Signaling Factors.

Objective: We recently developed the approach of using “microcolumns” of autologous full-thickness skin tissue for wound repair. The small size of these micro skin tissue columns (MSTCs, ∼0.5 mm in diameter) allows donor sites to heal quickly without scarring. Treatment with MSTCs significantly accelerate wound healing, and suppled various skin cell types and skin structures to replenish the wound volume. This technology is now starting clinical use. In this study, we investigate whether MSTCs may also influence wound healing by releasing soluble signaling factors.Approach: Freshly harvested MSTCs were incubated in culture medium for 24 h. The conditioned medium was collected and tested for its effects on migration and proliferation of human dermal fibroblasts, and its ability to induce tube formation by human umbilical vein endothelial cells (HUVECs). Proteins released into the conditioned medium were characterized by multiplex enzyme-linked immunosorbent assay (ELISA), and compared with medium conditioned by an equivalent mass of intact full-thickness skin.Results: MSTC-conditioned medium increased fibroblast migration and proliferation, as well as HUVEC tube formation. MSTCs released many soluble factors known to play prominent roles in wound healing. A subset of proteins showed significantly different release profiles compared with intact full-thickness skin.Innovation: The technology for harvesting and using MSTCs to augment wound healing was recently developed as an alternative to conventional autologous skin grafting. This study shows that MSTCs could also function as “cytokine factories.”Conclusion: In addition to supplying autologous cells to repopulate the wound volume, MSTCs can also function as a source of growth factors and cytokines to further enhance wound healing.

Promotion of Wound Healing and Prevention of Frostbite Injury in Rat Skin by Exopolysaccharide from the Arctic Marine Bacterium Polaribacter sp. SM1127.

Many marine microorganisms synthesize exopolysaccharides (EPSs), and some of these EPSs have been reported to have potential in different fields. However, the pharmaceutical potentials of marine EPSs are rarely reported. The EPS secreted by the Artic marine bacterium Polaribacter sp. SM1127 has good antioxidant activity, outstanding moisture-retention ability, and considerable protective property on human dermal fibroblasts (HDFs) at low temperature. Here, the effects of SM1127 EPS on skin wound healing and frostbite injury prevention were studied. Scratch wound assay showed that SM1127 EPS could stimulate the migration of HDFs. In the full-thickness cutaneous wound experiment of Sprague–Dawley (SD) rats, SM1127 EPS increased the wound healing rate and stimulated tissue repair detected by macroscopic observation and histologic examination, showing the ability of SM1127 EPS to promote skin wound healing. In the skin frostbite experiment of SD rats, pretreatment of rat skin with SM1127 EPS increased the rate of frostbite wound healing and promoted the repair of the injured skin significantly, indicating the good effect of SM1127 EPS on frostbite injury prevention. These results suggest the promising potential of SM1127 EPS in the pharmaceutical area to promote skin wound healing and prevent frostbite injury.

Derivation of Cell-Engineered Nanovesicles from Human Induced Pluripotent Stem Cells and Their Protective Effect on the Senescence of Dermal Fibroblasts.

Stem cells secrete numerous paracrine factors, such as cytokines, growth factors, and extracellular vesicles. As a kind of extracellular vesicle (EV), exosomes produced in the endosomal compartment of eukaryotic cells have recently emerged as a biomedical material for regenerative medicine, because they contain many valuable contents that are derived from the host cells, and can stably deliver those contents to other recipient cells. Although we have previously demonstrated the beneficial effects of human induced potent stem cell-derived exosomes (iPSC-Exo) on the aging of skin fibroblasts, low production yield has remained an obstacle for clinical applications. In this study, we generated cell-engineered nanovesicles (CENVs) by serial extrusion of human iPSCs through membrane filters with diminishing pore sizes, and explored whether the iPSC-CENV ameliorates physiological alterations of human dermal fibroblasts (HDFs) that occur by natural senescence. The iPSC-CENV exhibited similar characteristics to the iPSC-Exo, while the production yield was drastically increased compared to that of iPSC-derived EVs, including exosomes. The proliferation and migration of both young and senescent HDFs were stimulated by the treatment with iPSC-CENVs. In addition, it was revealed that the iPSC-CNEV restored senescence-related alterations of gene expression. Treatment with iPSC-CENVs significantly reduced the activity of senescence-associated-β-galactosidase (SA-β-Gal) in senescent HDFs, as well as suppressing the elevated expression of p53 and p21, key factors involved in cell cycle arrest, apoptosis, and cellular senescence signaling pathways. Taken together, these results suggest that iPSC-CENV could provide an excellent alternative to iPSC-exo, and be exploited as a resource for the treatment of signs of skin aging.

Substance P enhances cellular migration and inhibits senescence in human dermal fibroblasts under hyperglycemic conditions

Diabetes induces cellular dysfunction in dermal fibroblasts, such as impairment in migration, which is a major cause of chronic wound. Here, we demonstrated that the migration of human dermal fibroblasts was impaired under a high glucose culture condition. Substance P (SP) rescued the impaired migration of the fibroblasts. The activity of Rac1, Rho-associated kinase (ROCK), and Src was required for SP-mediated rescue of fibroblast migration. SP activated Rac1 and Src, whereas, NSC23766, a Rac1 inhibitor, and PP1 and PP2, Src inhibitors, inhibited SP-mediated enhancement of fibroblast migration. Y-27632, a ROCK inhibitor, inhibited the SP-mediated rescue of fibroblast migration. Senescence-associated β-galactosidase activity increased in human dermal fibroblasts cultured in a high glucose environment, but SP inhibited the β-galactosidase activity of the fibroblasts. These results suggest that SP promotes the migration of human dermal fibroblasts in diabetic-condition-mimicking cultures via the activity of Rac1, ROCK, and Src, and inhibits fibroblast senescence in hyperglycemic cultures.

Meltblown Polylactic Acid Nanowebs as a Tissue Engineering Scaffold.

Polylactic acid (PLA) nanofiber nonwovens have recently come under more vigorous investigation for their use as tissue engineering scaffolds owing to its ability to mimic the physical properties of naturally occurring human extracellular matrix in a variety of host tissues. Currently, the majority of available research on PLA nanowebs has focused on their creation through electrospinning. The goal of this study was to evaluate meltblown nonwoven webs made of nanodiameter PLA fibers for their application as a tissue engineering scaffold. Meltblown PLA fabrics were produced with a variety of different crystallinities, tensile moduli, and pore diameters. One fabric with mechanical properties similar to human dermis was selected as a scaffold to study attachment, proliferation, and migration of human dermal fibroblasts over 1, 3, 7, and 14 days without the use of additional cell adhesion molecules. The 3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide assay showed good proliferation from day 1 to 3 (P = 0.026) and up to 7 days of culture (P = 0.005) but without increase from day 7 to 14. Electron microscopy demonstrated adequate cellular attachment and surface migration at 1, 3, 7, and 14 days. Finally, confocal microscopy was used to investigate cellular penetration into the scaffolds. The investigation found that cells were able to penetrate fully through the thickness of the scaffold. The successes of this initial experiment are promising and confirm that meltblown nanofiber nonwovens are a viable avenue for tissue engineering scaffolds. Hopefully, these conclusions will open the door for others to pursue research in this exciting field.

Allogeneic platelet-rich plasma (PRP) is superior to platelets or plasma alone in stimulating fibroblast proliferation and migration, angiogenesis, and chemotaxis as relevant processes for wound healing.

Platelet-rich plasma (PRP) is frequently used in the treatment of acute and chronic wounds. One of the major problems concerning the use of PRP is the absence of a well-characterized and standardized product, which leads to a high variety in study outcomes. Therefore, more studies on the composition and standardization of PRP in wound healing are needed. Platelet concentrates derived from healthy blood donors were made in plasma (PC-plasma) or platelet additive solution (PC-PAS). The effects of PC-plasma, PC-PAS, and plasma were then tested on proliferation, differentiation, and migration of fibroblasts, as well as sprouting of endothelial cells in fibrin gels and chemotaxis of white blood cells (WBCs). PC-plasma stimulates the migration and proliferation of human dermal fibroblasts more than plasma or platelets alone. Furthermore, platelet factors decrease the expression of α-smooth muscle actin in dermal fibroblast cultures. PC-plasma also stimulates sprouting of endothelial cells. Finally, PC-plasma also acts as a strong chemoattractant for WBCs. Allogeneic PC-plasma has beneficial effects on various aspects of wound healing in vitro and is superior to plasma or platelets alone. PC-plasma is an attractive candidate for further in vivo evaluation.

Changes in the bioactive properties of strawberries caused by the storage in oxygen- and carbon dioxide-enriched atmospheres.

The changes in the antioxidant capacity, anti‐inflammatory, and wound healing properties of strawberry fruits as a consequence of the storage in atmospheres enriched in oxygen and carbon dioxide were investigated. Berries were exposed to two different gas compositions: 70% O2 + 20% CO2 and 90% O2 + 10% CO2, and stored for up to 20 days at 5°C. The antioxidant capacity, assessed through DPPH and FRAP methods, decreased around 17% in samples exposed to 70% O2 + 20% CO2 at day 20. However, the antioxidant activity of fruits stored in 90% O2 + 10% CO2 was maintained until day 20 and experienced an increase of around 10% on day 10. Moreover, strawberry stored in 90% O2 + 10% CO2 at days 5–10 showed an improved suppression of the pro‐inflammatory genes Cox‐2 and iNOS up to 30% higher than samples at day 0 in an in vitro LPS‐stimulated RAW 264.7 macrophage culture. In addition, berries exposed to 90% O2 + 10% CO2 at day 10 showed a human dermal fibroblast migration 30% higher than samples at day 0 in an in vitro skin‐fibroblast‐migration model. Therefore, evidence suggests that strawberry storage in 90% O2 + 10% CO2 can be a promissory alternative to offer fruits with enhanced bioactivity.

Fibronectin-derived Epiviosamines enhance PDGF-BB-stimulated human dermal fibroblast migration in vitro and granulation tissue formation in vivo.

Fibronectin (FN) is a multimodular glycoprotein that is a critical component of the extracellular matrix (ECM) anlage during embryogenesis, morphogenesis, and wound repair. Our laboratory has previously described a family of FN-derived peptides collectively called "epiviosamines" that enhance platelet-derived growth factor-BB (PDGF-BB)-driven tissue cell survival, speed burn healing, and reduce scarring. In this study, we used an agarose drop outmigration assay to report that epiviosamines can enhance PDGF-BB-stimulated adult human dermal fibroblast (AHDF) outmigration in a dose-dependent manner. Furthermore, these peptides can, when delivered topically, stimulate granulation tissue formation in vivo. A thiol-derivatized hyaluronan hydrogel cross-linked with polyethyleneglycol diacrylate (PEGDA) was used to topically deliver a cyclized epiviosamine: cP12 and a cyclized engineered variant of cP12 termed cNP8 to porcine, full-thickness, excisional wounds. Both cP12 and cNP8 exhibited dose-dependent increases in granulation tissue formation at day 4, with 600 μM cNP8 significantly enhancing new granulation tissue compared to vehicle alone. In contrast to previous studies, this study suggests that epiviosamines can be used to increase granulation tissue formation without an exogenous supply of PDGF-BB or any cell-binding peptides. Thus, epiviosamine may be useful topically to increase granulation tissue formation in acute wounds.

Infrared Skin‐Like Active Stretchable Electronics Based on Organic–Inorganic Composite Structures for Promotion of Cutaneous Wound Healing

AbstractRecent studies on flexible/stretchable medical electronics are almost all focusing on passive monitoring of physiological signs for medical diagnostics, but rare reports have been found on those for active therapeutic purposes. Here, a novel infrared skin‐like active stretchable electronics (ISASE) is introduced with the organic–inorganic composite design for promotion of cutaneous wound healing, which can be conformally mounted anywhere on the human body due to its excellent flexibility and stretchability. Comprehensive experiments, including the proliferation and migration of human skin fibroblasts and rat dermal fibroblasts in vitro, and various tests on wound healing of rats, show favorable effects of the ISASE on promoting the fibroblast migration and proliferation, reducing the inflammatory phase, stimulating the angiogenesis, and shorting the wound healing period. A typical ISASE significantly shortens the cure time for a wounded rat by at least two days compared with the normal treatment with 12 days cure. The mechanical tests confirm the validity of the ISASE when used in extreme large deformations (e.g., stretched by up to 80% strain), which enables the conformability with the human body. The present portable and wearable ISASE demonstrates great potential for cutaneous wound healing, which constitutes an important complement to the current applications in the healthcare field.

Polyelectrolyte nanocomplexes based on chitosan derivatives for wound healing application

Wound healing, when compromised, may be guided by biological cues such as Arg-Gly-Asp (RGD), a peptide known to induce cell adhesion and migration, eventually combined with adapted nanocarriers. Three different formulations were prepared and investigated in vitro for topical application. All formulations were based on carboxylated and trimethylated chitosan (CMTMC) displaying RGD. The polyelectrolyte nanocomplexes were prepared by mixing two oppositely charged polymers of CMTMC and chondroitin sulfate at different polymer ratios and subsequently characterized by dynamic light scattering and scanning electron microscopy. Hydrogels and foams with a high concentration of RGD-functionalized chitosan (3%) and hyaluronic acid (1.5%) that formed gel-embedded nanocomplexes were developed. In vitro assays showed absence of toxicity, ability to promote proliferation over 7 days and promotion of migration of human dermal fibroblasts treated with any of our formulations. These formulations were shown to be suitable for easy topical application and have the potential to accelerate wound healing.