Skin Regeneration Applications Research Articles

Enhancing Skin Regeneration Efficacy of Human Dermal Fibroblasts Using Carboxymethyl Cellulose-Coated Biodegradable Polymer.

Polylactic acid (PLA) is extensively used in the medical and cosmetic industries for skin regeneration and as a dermal filler due to its biocompatibility and biodegradability. However, the effectiveness of PLA as a cosmetic filler is limited by its slow degradation rate and poor cell attachment properties. Recent studies have focused on enhancing the performance of PLA by combining it with other materials. This study aimed to evaluate the performance of carboxymethyl cellulose (CMC), known for its high biocompatibility, in comparison with the widely used hyaluronic acid (HA). Two types of PLA-based particles, HA-PLA and CMC-PLA were synthesized by combining PLA with HA and CMC, respectively. After characterizing the particles, we evaluated cell adhesion and viability using human dermal fibroblasts and analyzed gene and protein expression related to cell attachment and angiogenic paracrine factors. The CMC-PLA particles maintained a more uniform size distribution than the HA-PLA particles and exhibited superior cell adhesion properties. Cells attached on the CMC-PLA particles showed enhanced secretion of angiogenic paracrine factors, suggesting a potential improvement in therapeutic efficacy. CMC-PLA particles demonstrated superior cell adhesion and secretion capabilities compared with HA-PLA particles, indicating their potential for application in skin regeneration and tissue recovery. Further research, including in vivo studies, is required to fully explore and validate the therapeutic potential of CMC-PLA particles.

Preparation of silk fibroin-derived hydrogels and applications in skin regeneration.

To compare different methods of preparing silk fibroin hydrogels, then summarize the applications of silk fibroin hydrogel-based scaffolds in skin regeneration and finally discuss about future prospects to inspire people interested in this field. A narrative review of the relevant papers was conducted. Notably, for applications in skin regeneration, this review provides a categorized summary and discussion of studies from the past decade. Silk fibroin is a naturally occurring, biocompatible biomaterial that is easily producible. Thanks to its exceptional processability, silk fibroin has found diverse applications in skin regeneration. These applications encompass sponges, fiber fabrics, thin films, and hydrogels. Hydrogels, in particular, are noteworthy due to their water-containing network structure, closely resembling natural tissues. They provide a biomimetic three-dimensional growth environment for cells and have the capacity to incorporate growth factors. Consequently, there are abundant studies of silk fibroin hydrogel-based scaffolds in skin regeneration. Besides, some commercialized medical devices are also made of silk fibroin. Silk fibroin hydrogel could be prepared with multiple methods and it is widely used in constructing scaffolds for efficient skin regeneration. In the future, silk fibroin hydrogel-based skin scaffolds could be more biomimetic and smart.

3D-bioprinted GelMA/gelatin/amniotic membrane extract (AME) scaffold loaded with keratinocytes, fibroblasts, and endothelial cells for skin tissue engineering

Gelatin-methacryloyl (GelMA) is a highly adaptable biomaterial extensively utilized in skin regeneration applications. However, it is frequently imperative to enhance its physical and biological qualities by including supplementary substances in its composition. The purpose of this study was to fabricate and characterize a bi-layered GelMA-gelatin scaffold using 3D bioprinting. The upper section of the scaffold was encompassed with keratinocytes to simulate the epidermis, while the lower section included fibroblasts and HUVEC cells to mimic the dermis. A further step involved the addition of amniotic membrane extract (AME) to the scaffold in order to promote angiogenesis. The incorporation of gelatin into GelMA was found to enhance its stability and mechanical qualities. While the Alamar blue test demonstrated that a high concentration of GelMA (20%) resulted in a decrease in cell viability, the live/dead cell staining revealed that incorporation of AME increased the quantity of viable HUVECs. Further, gelatin upregulated the expression of KRT10 in keratinocytes and VIM in fibroblasts. Additionally, the histological staining results demonstrated the formation of well-defined skin layers and the creation of extracellular matrix (ECM) in GelMA/gelatin hydrogels during a 14-day culture period. Our study showed that a 3D-bioprinted composite scaffold comprising GelMA, gelatin, and AME can be used to regenerate skin tissues.

Fabrication, Characterization and Wound-Healing Properties of Core-Shell SF@chitosan/ZnO/Astragalus Arbusculinus Gum Nanofibers.

Silk fibroin/chitosan/ZnO/Astragalus arbusculinus (Ast) gum fibrous scaffolds along with adipose-derived mesenchymal stem cells (ADSCs) were investigated for accelerating diabetic wound healing. Scaffolds with a core-shell structure and different compositions were synthesized using the electrospinning method. Biological in vitro investigations included antibacterial testing, cell viability analysis and cell attachment evaluation. In vivo experiments, including the chicken chorioallantoic membrane (CAM) test, were conducted to assess wound-healing efficacy and histopathological changes. The incorporation of Ast to the silk fibroin@ chitosan/ZnO scaffold improved wound healing in diabetic mice. In addition, seeding of ADSCs on the scaffold accelerated wound healing. These findings suggest that the designed scaffold can be useful for skin regeneration applications.

Bioactive self-assembling silk fibroin–sericin films for skin tissue engineering

The quest for an ideal wound dressing material has been a strong motivation for researchers to explore novel biomaterials for this purpose. Such explorations have led to the extensive use of silk fibroin (SF) as a suitable polymer for several applications over the years. Unfortunately, another major silk protein—sericin has not received its due attention yet in spite of having favorable biological properties. In this study, we report an approach of blending SF and silk sericin (SS) without the usage of chemical crosslinkers is made possible by the usage of formic acid which evaporates to induce β-sheets formation to form cytocompatible films. Raman spectroscopy confirms the presence of SF/SS components in blend and formation of β-sheet in films. In situ, gelation kinetics studies were conducted to understand the change in gelation properties with addition of sericin into SF. Methyl thiazolyl tetrazolium and live/dead assays were performed to study cellular attachment, viability and proliferation on SF/SS films. The antibacterial properties of SF/SS films were tested using Gram-negative and Gram-positive bacteria. The re-structured SF/SS films were stable, transparent, show good mechanical properties, antibacterial activity and cytocompatibility, therefore can serve as suitable biomaterial candidates for skin regeneration applications.

Controlled therapeutic cholesterol delivery to cells for the proliferation and differentiation of keratinocytes.

The challenge of enhancing wound healing and skin regeneration, particularly in conditions like burns and diabetic wounds, necessitates innovative solutions. Cholesterol, often associated with cardiovascular diseases, plays vital roles in cellular functions, maintaining skin integrity and preserving the skin barrier. Here, we explore cholesterol's significance, its influence on keratinocytes, and its potential application in skin regeneration. The study utilizes electrospun polyimide (PI) fibers as a cholesterol carrier model and investigates its impact on HaCaT keratinocytes, marking the first time tracked cholesterol delivery from the scaffold into cells. We demonstrate that an optimal concentration of 0.7 mM cholesterol in the medium enhances cell proliferation, while higher concentrations have negative effects. Cholesterol-enriched scaffolds significantly increase cell proliferation and replicative activity, especially in a 3D culture environment. Moreover, cholesterol influences keratinocyte differentiation, promoting early differentiation while inhibiting late differentiation. These findings suggest that cholesterol-loaded scaffolds can have applications in wound healing by promoting cell growth, regulating differentiation, and potentially accelerating wound closure. Further research in this area will lead to innovative wound management and tissue regeneration strategies.

Development of a Temperature-Responsive Hydrogel Incorporating PVA into NIPAAm for Controllable Drug Release in Skin Regeneration.

Melanoma, a highly malignant and aggressive form of skin cancer, poses a significant global health threat, with limited treatment options and potential side effects. In this study, we developed a temperature-responsive hydrogel for skin regeneration with a controllable drug release. The hydrogel was fabricated using an interpenetrating polymer network (IPN) of N-isopropylacrylamide (NIPAAm) and poly(vinyl alcohol) (PVA). PVA was chosen for its adhesive properties, biocompatibility, and ability to address hydrophobicity issues associated with NIPAAm. The hydrogel was loaded with doxorubicin (DOX), an anticancer drug, for the treatment of melanoma. The NIPAAm-PVA (N-P) hydrogel demonstrated temperature-responsive behavior with a lower critical solution temperature (LCST) around 34 °C. The addition of PVA led to increased porosity and faster drug release. In vitro biocompatibility tests showed nontoxicity and supported cell proliferation. The N-P hydrogel exhibited effective anticancer effects on melanoma cells due to its rapid drug release behavior. This N-P hydrogel system shows great promise for controlled drug delivery and potential applications in skin regeneration and cancer treatment. Further research, including in vivo studies, will be essential to advance this hydrogel system toward clinical translation and impactful advancements in regenerative medicine and cancer therapeutics.

The Synergistic Effect of Electrical Stimulation and Dermal Fibroblast Cells-Laden 3D Conductive Hydrogel for Full-Thickness Wound Healing.

Clinically, most patients with poor wound healing suffer from generalized skin damage, usually accompanied by other complications, so developing therapeutic strategies for difficult wound healing has remained extremely challenging until now. Current studies have indicated that electrical stimulation (ES) to cutaneous lesions enhances skin regeneration by activating intracellular signaling cascades and secreting skin regeneration-related cytokine. In this study, we designed different concentrations of graphene in gelatin-methacrylate (GelMa) to form the conductive composite commonly used in wound healing because of its efficiency compared to other conductive thermo-elastic materials. The results demonstrated the successful addition of graphene to GelMa while retaining the original physicochemical properties of the GelMa bioink. In addition, the incorporation of graphene increased the interactions between these two biomaterials, leading to an increase in mechanical properties, improvement in the swelling ratio, and the regulation of degradation characteristics of the biocomposite scaffolds. Moreover, the scaffolds exhibited excellent electrical conductivity, increasing proliferation and wound healing-related growth factor secretion from human dermal fibroblasts. Overall, the HDF-laden 3D electroconductive GelMa/graphene-based hydrogels developed in this study are ideal biomaterials for skin regeneration applications in the future.

Engineering exosome-based biomimetic nanovehicles for wound healing.

Complexity and difficulties in wound management are pressing concerns that affect patients' quality of life and may result in tissue infection, necrosis, and loss of local and systemic functions. Hence, novel approaches to accelerate wound healing are being actively explored over the last decade. Exosomes as important mediators of intercellular communications are promising natural nanocarriers due to their biocompatibility, low immunogenicity, drug loading and targeting capacities, and innate stability. More importantly, exosomes are developed as a versatile pharmaceutical engineering platform for wound repair. This review provides an overview of the biological and physiological functions of exosomes derived from a variety of biological origins during wound healing phases, strategies for exosomal engineering, and therapeutic applications in skin regeneration.

Recent progress in polymeric biomaterials and their potential applications in skin regeneration and wound care management

Recent progress in polymeric biomaterials and their potential applications in skin regeneration and wound care management

Silicon-Based Scaffold for Wound Healing Skin Regeneration Applications: A Concise Review.

Silicon has made its breakthrough in various industries, including clinical and biomedical applications. Silicon-based biomaterials that were fabricated into various types of scaffolds may attract interest due to their highly favorable properties covering their excellent biocompatibility, high surface area, mechanical strength, and selectivity depending on their application including film, hydrogel, nanoparticles, and so on. Silicon-based materials have also shown exciting results involving cell culture, cell growth, as well as tissue engineering. In this article, a simple review compromising the evaluation of silicon’s unique properties has been discussed and followed by the application of the silicone-based product in future perspectives in biomedical fields. The review goals are to widen and inspire broader interest in silicone-based materials in wound healing research.

The 3D printed conductive grooved topography hydrogel combined with electrical stimulation for synergistically enhancing wound healing of dermal fibroblast cells

Patients with extensive cutaneous damage resulting from poor wound healing often have other comorbidities such as diabetes that may lead to impaired skin functions and scar formation. Many recent studies have shown that the application of electrical stimulation (ES) to cutaneous lesions significantly improves skin regeneration via activation of AKT intracellular signaling cascades and secretion of regeneration-related growth factors. In this study, we fabricated varying concentrations of gelatin-methacrylate (GelMa) hydrogels with poly(3,4-ethylenedioxythiophene) (PEDOT): polystyrene sulfonate (PSS), which is a conductive material commonly used in tissue engineering due to its efficiency among conductive thermo-elastic materials. The results showed successful modification of PEDOT:PSS with GelMa while retaining the original structural characteristics of the GelMa hydrogels. In addition, the incorporation of PEDOT:PSS increased the interactions between both the materials, thus leading to enhanced mechanical strength, improved swelling ratio, and decreased hydrophilicity of the scaffolds. Our GelMa/PEDOT:PSS scaffolds were designed to have micro-grooves on the surfaces of the scaffolds for the purpose of directional guiding. In addition, our scaffolds were shown to have excellent electrical conductivity, thus leading to enhanced cellular proliferation and directional migration and orientation of human dermal fibroblasts. In vivo studies revealed that the GelMa/PEDOT:PSS scaffolds with electrical stimulation were able to induce full skin thickness regeneration, as seen from the various stainings. These results indicate the potential of GelMa/PEDOT:PSS as an electro-conductive biomaterial for future skin regeneration applications.

State-of-the-Art Review of Electrospun Gelatin-Based Nanofiber Dressings for Wound Healing Applications.

Electrospun nanofiber materials have been considered as advanced dressing candidates in the perspective of wound healing and skin regeneration, originated from their high porosity and permeability to air and moisture, effective barrier performance of external pathogens, and fantastic extracellular matrix (ECM) fibril mimicking property. Gelatin is one of the most important natural biomaterials for the design and construction of electrospun nanofiber-based dressings, due to its excellent biocompatibility and biodegradability, and great exudate-absorbing capacity. Various crosslinking approaches including physical, chemical, and biological methods have been introduced to improve the mechanical stability of electrospun gelatin-based nanofiber mats. Some innovative electrospinning strategies, including blend electrospinning, emulsion electrospinning, and coaxial electrospinning, have been explored to improve the mechanical, physicochemical, and biological properties of gelatin-based nanofiber mats. Moreover, numerous bioactive components and therapeutic agents have been utilized to impart the electrospun gelatin-based nanofiber dressing materials with multiple functions, such as antimicrobial, anti-inflammation, antioxidation, hemostatic, and vascularization, as well as other healing-promoting capacities. Noticeably, electrospun gelatin-based nanofiber mats integrated with specific functions have been fabricated to treat some hard-healing wound types containing burn and diabetic wounds. This work provides a detailed review of electrospun gelatin-based nanofiber dressing materials without or with therapeutic agents for wound healing and skin regeneration applications.

Functionalized chitosan/spherical nanocellulose-based hydrogel with superior antibacterial efficiency for wound healing

Cellulose nanomaterials have received significant interest due to their superior physicochemical properties and biocompatibility. The nanomaterials-based hydrogel patches are widely explored for skin regeneration. However, the injectability and adhesiveness of the hydrogels are crucial challenges for tissue engineering applications. To overcome these, we synthesized an injectable and adhesive hydrogel of spherical nanocellulose (s-NC) reinforced carboxymethyl chitosan for rapid skin regeneration. The s-NC exhibited improved cellular activity than cellulose nanocrystals. The hydrogels exhibited adhesive and injectability potentials and were molded in the desired configurations. An enhanced conductivity was observed in s-NC added hydrogels than the pure polymer hydrogel. The skin regeneration potential of the hydrogel scaffolds was also examined in the rats using the wound healing model. The composite scaffolds also showed improved antibacterial potential. Taken together, the developed hydrogels have the potential and can be explored as a promising biomaterial for enhanced skin regeneration applications.

The diameter factor of aligned membranes facilitates wound healing by promoting epithelialization in an immune way

Topographical properties, such as pattern and diameter, of biomaterials play important roles in influencing cell activities and manipulating the related immune response during wound healing. We prepared aligned electrospinning membranes with different fiber diameters, including 319 ± 100 nm (A300), 588 ± 132 nm (A600), and 1048 ± 130 nm (A1000), by adjusting the distance from the tip to the collector, the injection rate, and the concentration of the solution. The A300 membranes significantly improved cell proliferation and spreading and facilitated wound healing (epithelization and vascularization) with the regeneration of immature hair follicles compared to the other membranes. Transcriptomics revealed the underlying molecular mechanism that A300 could promote immune-related processes towards a pro-healing direction, significantly promoting keratinocyte migration and skin wound healing. All the results indicated that wound healing requires the active participation of the immune process, and that A300 was a potential candidate for guided skin regeneration applications.

Epithelial Growth Factor-Anchored on Polycaprolactone/6-deoxy-6-amino-β-cyclodextrin Nanofibers: In Vitro and In Vivo Evaluation

Polycaprolactone (PCL) is a well-known FDA approved biomaterial for tissue engineering. However, its hydrophobic properties limit its use for skin wound healing which makes its functionalization necessary. In this work, we present the fabrication and evaluation of PCL nanofibers by the electrospinning technique, as well as PCL functionalized with 6-deoxy-6-amino-β-cyclodextrin (aminated nanofibers). Afterwards, epithelial growth factor (EGF) was anchored onto hydrophilic PCL/deoxy-6-amino-β-cyclodextrin. The characterization of the three electrospun fibers was made by means of field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR); Confocal-Raman Spectroscopy were used for elucidated the chemical structure, the hydrophilicity was determined by Contact Angle (CA). In vitro cell proliferation test was made by seeding embryonic fibroblast cell line (3T3) onto the electrospun mats and in vivo studies in a murine model were conducted to prove its effectivity as skin wound healing material. The in vitro studies showed that aminated nanofibers without and with EGF had 100 and 150% more cell proliferation of 3T3 cells against the PCL alone, respectively. In vivo results showed that skin wound healing in a murine model was accelerated by the incorporation of the EGF. In addition, the EGF had favorable effects in epidermal cell proliferation. The study demonstrates that a protein of high biological interest like EGF can be attached covalently to the surface of a synthetic material enriched with amino groups. This kind of biomaterial has a great potential for applications in skin regeneration and wound healing.

Fabrication and Characterization of Polyvinylpyrrolidone-Eggshell Membrane-Reduced Graphene Oxide Nanofibers for Tissue Engineering Applications.

One of the best methods to prevent wound infection and speed up wound healing is wound dressing based on nanofiber–polymer scaffolds, which have acceptable antimicrobial performance and appropriate skin regeneration capabilities. In this paper, the electrospinning method was applied to synthesize the polyvinylpyrrolidone-acrylic acid hydrogel (PVPA)–eggshell membrane (ESM)–reduced graphene oxide (rGO) nanosheets nanocomposite dressings with different reduced graphene oxide contents (0, 0.5, 1, and 2 wt.%). Thus, smooth nanofibers were fabricated, including a high amount of rGO, which reduced the fiber diameter. Based on the results, rGO played an important role in water impermeability. The results showed that by increasing the rGO concentration from 0.5 to 2 wt%, the contact angle value increased persistently. Results showed that compared to PVPA–ESM, the mechanical strength and strain of PVPA–ESM/1 wt% rGO significantly enhanced 28% and 23%, respectively. Incorporation of 1 wt% rGO enhanced swelling ratio from 875% for PVPA-ESM to 1235% after 420 min, while increasing the rGO to 2 wt% increased the degradation rate of the composites. According to the in vitro cell culture studies, PVPA-ESM wound dressings with 0.5–1 wt% rGO content enhanced PC12 cell viability compared to the wound dressings without rGO nanosheets. Generally, rGO–loaded PVPA-ESM nanofiber wound dressing can be considered as a potential candidate to be used in skin regeneration applications.

Designing hybrid nanofibers based on keratin-poly (vinyl alcohol) and poly (Ɛ-caprolactone) for application as wound dressing

In this study, the production of hybrid scaffolds containing keratin/polyvinyl alcohol (Ker/PVA) and poly (Ɛ-caproactone) (PCL) for application in skin regeneration has been investigated. In the first step, the extraction of keratin from wool fibers was done, and then electrospinning process was used to fabricate hybrid nanofibers. Ker/PVA blend solution was extruded from one syringe and poly(ε-caprolactone) solution from the other one and hybrid nanofibers were gathered onto a rotary drum collector. The effect of different ratios of Ker/PVA (30:70), (50:50), and (70:30) with PCL were studied on the morphology, hydrophilicity and mechanical features of the scaffolds. The Ker/PVA (50:50)-PCL nanofibers presented an appropriate modulus and mechanical strength similar to the natural skin. These scaffolds possessed high levels of hydrophilicity, which improved cell-scaffold adhesion and increased the growth and proliferation of fibroblast cells. Keratin based nanofibers demonstrated antibacterial characteristic against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus.

New prospects in skin regeneration and repair using nanophased hydroxyapatite embedded in collagen nanofibers

This study reflects an exploitation of a composite matrix produced by electrospinning of collagen and electrospraying of nanophased hydroxyapatite (nanoHA), for skin regeneration applications. The main goal was to evaluate the effect of nanoHA, as source of localized calcium delivery, on human dermal fibroblasts, keratinocytes, and human mesenchymal stem cells (hMSCs) growth, proliferation, differentiation, and extracellular matrix production. This study revealed that calcium ions provided by nanoHA significantly enhanced cellular growth and proliferation rates and prevented adhesion of pathogenic bacteria strains typically found in human skin flora. Moreover, hMSCs were able to differentiate in both osteogenic and adipogenic lineages. Rat subcutaneous implantation of the membranes also revealed that no adverse reaction occurred. Therefore, the mechanically fit composite membrane presents a great potential to be used either as cell transplantation scaffold for skin wound regeneration or as wound dressing material in plastic surgery, burns treatment or skin diseases.

Calcium Silicate-Activated Gelatin Methacrylate Hydrogel for Accelerating Human Dermal Fibroblast Proliferation and Differentiation.

Wound healing is a complex process that requires specific interactions between multiple cells such as fibroblasts, mesenchymal, endothelial, and neural stem cells. Recent studies have shown that calcium silicate (CS)-based biomaterials can enhance the secretion of growth factors from fibroblasts, which further increased wound healing and skin regeneration. In addition, gelatin methacrylate (GelMa) is a compatible biomaterial that is commonly used in tissue engineering. However, it has low mechanical properties, thus restricting its fullest potential for clinical applications. In this study, we infused Si ions into GelMa hydrogel and assessed for its feasibility for skin regeneration applications by observing for its influences on human dermal fibroblasts (hDF). Initial studies showed that Si could be successfully incorporated into GelMa, and printability was not affected. The degradability of Si-GelMa was approximately 20% slower than GelMa hydrogels, thus allowing for better wound healing and regeneration. Furthermore, Si-GelMa enhanced cellular adhesion and proliferation, therefore leading to the increased secretion of collagen I other important extracellular matrix (ECM) remodeling-related proteins including Ki67, MMP9, and decorin. This study showed that the Si-GelMa hydrogels were able to enhance the activity of hDF due to the gradual release of Si ions, thus making it a potential candidate for future skin regeneration clinical applications.