Tailoring biomaterials for skin anti-aging.

Skin aging is the phenomenon of degenerative changes in the structure and function of skin tissues over time and is manifested by a gradual loss of skin elasticity and firmness, an increased number of wrinkles, and hyperpigmentation. Skin anti-aging refers to a reduction in the skin aging phenomenon through medical cosmetic technologies. In recent years, new biomaterials have been continuously developed for improving the appearance of the skin through mechanical tissue filling, regulating collagen synthesis and degradation, inhibiting pigmentation, and repairing the skin barrier. This review summarizes the mechanisms associated with skin aging, describes the biomaterials that are commonly used in medical aesthetics and their possible modes of action, and discusses the application strategies of biomaterials in this area. Moreover, the synergistic effects of such biomaterials and other active ingredients, such as stem cells, exosomes, growth factors, and antioxidants, on tissue regeneration and anti-aging are evaluated. Finally, the possible challenges and development prospects of biomaterials in the field of anti-aging are discussed, and novel ideas for future innovations in this area are summarized.

Developing fibrin-based biomaterials/scaffolds in tissue engineering.

Tissue engineering technology has advanced rapidly in recent years, offering opportunities to construct biologically active tissues or organ substitutes to repair or even enhance the functions of diseased tissues and organs. Tissue-engineered scaffolds rebuild the extracellular microenvironment by mimicking the extracellular matrix. Fibrin-based scaffolds possess numerous advantages, including hemostasis, high biocompatibility, and good degradability. Fibrin scaffolds provide an initial matrix that facilitates cell migration, differentiation, proliferation, and adhesion, and also play a critical role in cell-matrix interactions. Fibrin scaffolds are now widely recognized as a key component in tissue engineering, where they can facilitate tissue and organ defect repair. This review introduces the properties of fibrin, including its composition, structure, and biology. In addition, the modification and cross-linking modes of fibrin are discussed, along with various forms commonly used in tissue engineering. We also describe the biofunctionalization of fibrin. This review provides a detailed overview of the use and applications of fibrin in skin, bone, and nervous tissues, and provides novel insights into future research directions for clinical treatment.

DNA hydrogels and their derivatives in biomedical engineering applications.

Deoxyribonucleotide (DNA) is uniquely programmable and biocompatible, and exhibits unique appeal as a biomaterial as it can be precisely designed and programmed to construct arbitrary shapes. DNA hydrogels are polymer networks comprising cross-linked DNA strands. As DNA hydrogels present programmability, biocompatibility, and stimulus responsiveness, they are extensively explored in the field of biomedicine. In this study, we provide an overview of recent advancements in DNA hydrogel technology. We outline the different design philosophies and methods of DNA hydrogel preparation, discuss its special physicochemical characteristics, and highlight the various uses of DNA hydrogels in biomedical domains, such as drug delivery, biosensing, tissue engineering, and cell culture. Finally, we discuss the current difficulties facing DNA hydrogels and their potential future development.

Integration of single-cell and bulk RNA sequencing data reveals that CYTOR is a potential prognostic and immunotherapeutic response marker for skin cutaneous melanoma.

Skin cutaneous melanoma (SKCM) is a highly malignant tumor that is prone to immune escape and distant metastasis. Immunotherapy is considered to be the best treatment for patients with SKCM. However, not all patients benefit from it. We observed a significant differential expression of the lncRNA CYTOR in patients with SKCM based on single-cell and bulk RNA sequencing data mining results. The results showed that compared to normal tissue lncRNA CYTOR expression was significantly upregulated in SKCM tissue. Subsequently, we validated this finding in clinical samples, and we also found that the expression of lncRNA CYTOR in SKCM was higher as it progressed. lncRNA CYTOR was differentially expressed in patients who responded to immunotherapy, suggesting that it may serve as a biomarker to predict the efficacy of SKCM immunotherapy. In-depth analysis revealed that lncRNA CYTOR expression was strongly correlated with immune cell infiltration, immune response, and immune checkpoint expression. Meanwhile, our experiments revealed that CYTOR affects SKCM cell invasion and clone formation and is associated with the activation of the EMT pathway. In summary, our findings illustrate, for the first time, the value of CYTOR as a potential prognostic and immunotherapeutic response marker in SKCM.

Exosomes-carried curcumin based on polysaccharide hydrogel promote flap survival.

Flap grafting is a common technique used to repair skin defects in orthopedics and plastic and reconstructive surgeries. However, oxidative stress injury caused by ischemia and ischemia-reperfusion injury at the distal end of the skin flap can cause flap necrosis. Curcumin is a natural compound with anti-inflammatory and antioxidant properties that tackle oxidative stress. However, its applicability is limited by its poor water solubility. Exosomes are membranous vesicles that can be loaded with hydrophobic drugs. They are widely studied in drug delivery applications and can be investigated to augment curcumin efficiency. In this study, a self-healing oxidized pullulan polysaccharide-carboxymethylated chitosan composite hydrogel was used as a curcumin-loaded exosome delivery system to evaluate its impact on the viability of skin flaps. The hydrogel exhibited good self-healing properties that allowed the continuous and stable release of drugs. It had anti-inflammatory and antioxidant properties that could reduce oxidative stress damage due to early ischemia and hypoxia of the skin flap in vitro. Moreover, this composite hydrogel attenuated inflammatory responses, promoted angiogenesis, and reduced the distal necrosis of the flap in vivo. Therefore, our hydrogel provides a novel strategy for skin flap graft protection with reduced necrosis and the potential for broad clinical applications.

Biomarker Potential of LINC00313 in Head and Neck Squamous Cell Carcinoma: Correlation with Epithelial-Mesenchymal Transition and Immune Cell Infiltration.

Although LINC00313 is dysregulated in several tumors, its role in head and neck squamous cell carcinoma (HNSC) is not fully understood. The aim of this study was to analyze the role of LINC00313 in HNSC. The clinical information and LINC00313 expression data of HNSC were mined from the TCGA/GEO/cbioportal database. The correlation between LINC00313 expression and immune cell infiltration in HNSC tumors was analyzed by bioinformatics and gene enrichment analysis was performed. LINC00313 was silenced in HNSC cell lines, and changes at the genetic and molecular levels were verified through qRT-PCR and Western blotting. The researchers also validated its functional phenotype through a series of cell function experiments. The results showed that overexpression and copy number variation of LINC00313 in HNSC were associated with poorer prognosis. In addition, LINC00313 expression was significantly negatively correlated with immune cell infiltration. Silencing of LINC00313 in HNSC cells significantly reduced the rate of cell migration. LINC00313 may affect the progression of HNSC by regulating epithelial-mesenchymal transition. In conclusion, LINC00313 is a potential biomarker of HNSC prognosis and a potential target for immunotherapy.

Nanosphere-reinforced polysaccharide self-healing hydrogels for infected wound healing.

Bacterial infection remarkably impedes wound healing, with antibiotics traditionally serving as the primary therapeutic intervention. However, the escalating misuse of antibiotics and the emergence of bacterial resistance present substantial treatment challenges for infected wounds. Consequently, the development of antibiotic-free antimicrobial dressings holds pertinent research and clinical relevance. To this end, this study aimed to introduce an all-natural hydrogel dressing, amalgamating polyphenols and polysaccharides, exhibiting pronounced antibacterial and antioxidant properties without relying on antibiotics. First, we constructed curcumin-tannic acid­zinc ion nanospheres (CTZN) through self-assembly. Our experimental results showed that the nanospheres had excellent biocompatibility, antioxidant, and antimicrobial abilities. Subsequently, we prepared carboxymethylated chitosan/oxidized sodium alginate hydrogels via Schiff base reactions. Incorporation of CTZN into the hydrogel system not only improves the inherent qualities of the hydrogel but also confers multifunctional properties, including antimicrobial, antioxidant, and anti-inflammatory abilities. In this study, we enhanced the physicochemical properties and biological activity of hydrogels by introducing natural material nanospheres, offering a novel approach that could pave the way for the development of purely natural biomaterial dressings.

Microenvironment Remodeling Self-Healing Hydrogel for Promoting Flap Survival.

Random flap grafting is a routine procedure used in plastic and reconstructive surgery to repair and reconstruct large tissue defects. Flap necrosis is primarily caused by ischemia-reperfusion injury and inadequate blood supply to the distal flap. Ischemia-reperfusion injury leads to the production of excessive reactive oxygen species, creating a pathological microenvironment that impairs cellular function and angiogenesis. In this study, we developed a microenvironment remodeling self-healing hydrogel [laminarin-chitosan-based hydrogel-loaded extracellular vesicles and ceria nanozymes (LCH@EVs&CNZs)] to improve the flap microenvironment and synergistically promote flap regeneration and survival. The natural self-healing hydrogel (LCH) was created by the oxidation laminarin and carboxymethylated chitosan via a Schiff base reaction. We loaded this hydrogel with CNZs and EVs. CNZs are a class of nanomaterials with enzymatic activity known for their strong scavenging capacity for reactive oxygen species, thus alleviating oxidative stress. EVs are cell-secreted vesicular structures containing thousands of bioactive substances that can promote cell proliferation, migration, differentiation, and angiogenesis. The constructed LCH@EVs&CNZs demonstrated a robust capacity for scavenging excess reactive oxygen species, thereby conferring cellular protection in oxidative stress environments. Moreover, these constructs notably enhance cell migration and angiogenesis. Our results demonstrate that LCH@EVs&CNZs effectively remodel the pathological skin flap microenvironment and marked improve flap survival. This approach introduces a new therapeutic strategy combining microenvironmental remodeling with EV therapy, which holds promise for promoting flap survival.

Construction of intelligent drug delivery system based on polysaccharide-derived polymer micelles: A review.

Micelles are nanostructures developed via the spontaneous assembly of amphiphilic polymers in aqueous systems, which possess the advantages of high drug stability or active-ingredient solubilization, targeted transport, controlled release, high bioactivity, and stability. Polysaccharides have excellent water solubility, biocompatibility, and degradability, and can be modified to achieve a hydrophobic core to encapsulate hydrophobic drugs, improve drug biocompatibility, and achieve regulated delivery of the loaded drug. Micelles drug delivery systems based on polysaccharides and their derivatives show great potential in the biomedical field. This review discusses the principles of self-assembly of amphiphilic polymers and the formation of micelles; the preparation of amphiphilic polysaccharides is described in detail, and an overview of common polysaccharides and their modifications is provided. We focus on the review of strategies for encapsulating drugs in polysaccharide-derived polymer micelles (PDPMs) and building intelligent drug delivery systems. This review provides new research directions that will help promote future research and development of PDPMs in the field of drug carriers.

Natural self-healing injectable hydrogels loaded with exosomes and berberine for infected wound healing.

Complete and rapid healing of infected skin wounds remains a challenge in current clinical treatment. In this study, we prepared a self-healing injectable CK hydrogel by crosslinking two natural polysaccharides, carboxymethyl chitosan and oxidized konjac glucomannan, based on the Schiff base bond. To enhance the biological function of the hydrogel, we multi-functionalized hydrogen by loading it with berberine (BBR) and stem cell-derived exosomes (Exo), forming a composite hydrogel, CK@BBR&Exo, which could be injected directly into the wound through a needle and adhered to the wound. Furthermore, the self-healing properties of CK@BBR&Exo increased its usefulness and service life. Additionally, the drug-loaded CK@BBR&Exo hydrogel was versatile, inhibiting bacterial growth, regulating the inflammatory response, and promoting neovascularization in infected skin wounds, thus achieving the rapid healing of infected skin wounds. These results suggest that the CK@BBR&Exo-injectable self-healing hydrogel is an ideal dressing for treating infected skin wounds.

TNFSF10, an autophagy related gene, was a prognostic and immune infiltration marker in skin cutaneous melanoma.

Autophagy exerts a pivotal effect on skin cutaneous melanoma (SKCM). This study was aimed to investigate the expression of autophagy related genes (ARGs) in SKCM as well as its clinical value. Differentially expressed (DE) ARGs were downloaded from the intersection of SKCM data in GEPIA2 database and ARGs in Human Autophagy Database (HADB) database, and were verified in SKCM datasets GSE46517 and GSE15605. DE ARGs were enriched by Metascape online tools. According to GEPIA2 database, tumor necrosis factor-related apoptosis-inducing ligand (TNFSF10) was identified as a closely related factor and prognostic marker of SKCM. Then the correlation analysis of clinicopathological characteristics between TNFSF10 and SKCM was completed by several online tools such as TISCH, HPA, BEST and qRT-PCR. Subsequently, we investigated TNFSF10 related functions and signal pathways with LinkedOmics online tool, and immune infiltration using Assistant for Clinical Bioinformatics online tool. Furthermore, correlation analysis between TNFSF10 expression and immunotherapy response was performed by TIDE algorithm and BEST online tool. And Kaplan-Meier Plotter was used to assessing the prognosis of SKCM patients receiving immunotherapy. Finally, the correlation analysis among TNFSF10 methylation, TNFSF10 expression and patient prognosis was completed by the DiseaseMeth version 2.0, UCSC XENA and qRT-PCR. ARGs are DE in SKCM and participate in the ERBB signaling pathway, as well as the processing and presentation of antigens. Moreover, TNFSF10's expression along with methylation expression were significantly associated with the prognosis. Low expression of TNFSF10 was associated with malignant clinicopathological features, lower immune signal activity and lower immunocytes abundance in patients with SKCM. As an ARG, TNFSF10 has a potential capacity in predicting the prognosis of SKCM patients, meanwhile, may be a novel immunotherapy marker for SKCM.

Zn2+ incorporated composite polysaccharide microspheres for sustained growth factor release and wound healing.

The development of new wound dressings has always been an issue of great clinical importance and research promise. In this study, we designed a novel double cross-linked polysaccharide hydrogel microspheres based on alginate (ALG) and hyaluronic acid methacrylate (HAMA) from gas-assisted microfluidics for wound healing. The microspheres from gas-assisted microfluidics showed an uniform size and good microsphere morphology. Moreover, this composite polysaccharide hydrogel microspheres were constructed by harnessing the fact that zinc ions (Zn2+) can cross-link with ALG as well as histidine-tagged vascular endothelial growth (His-VEGF) to achieve long-term His-VEGF release, thus promoting angiogenesis and wound healing. Meanwhile, Zn2+, as an important trace element, can exert antibacterial and anti-inflammatory effects, reshaping the trauma microenvironment. In addition, photo cross-linked HAMA was introduced into the microspheres to further improve its mechanical properties and drug release ability. In summary, this novel Zn2+ composite polysaccharide hydrogel microspheres loaded with His-VEGF based on a dual cross-linked strategy exhibited synergistic antimicrobial and angiogenic effects in promoting wound healing.

Biomaterial-based gene therapy.

Gene therapy, a medical approach that involves the correction or replacement of defective and abnormal genes, plays an essential role in the treatment of complex and refractory diseases, such as hereditary diseases, cancer, and rheumatic immune diseases. Nucleic acids alone do not easily enter the target cells due to their easy degradation in vivo and the structure of the target cell membranes. The introduction of genes into biological cells is often dependent on gene delivery vectors, such as adenoviral vectors, which are commonly used in gene therapy. However, traditional viral vectors have strong immunogenicity while also presenting a potential infection risk. Recently, biomaterials have attracted attention for use as efficient gene delivery vehicles, because they can avoid the drawbacks associated with viral vectors. Biomaterials can improve the biological stability of nucleic acids and the efficiency of intracellular gene delivery. This review is focused on biomaterial-based delivery systems in gene therapy and disease treatment. Herein, we review the recent developments and modalities of gene therapy. Additionally, we discuss nucleic acid delivery strategies, with a focus on biomaterial-based gene delivery systems. Furthermore, the current applications of biomaterial-based gene therapy are summarized.

SMG7-AS1 as a prognostic biomarker and predictor of immunotherapy responses for skin cutaneous melanoma.

Skin cutaneous melanoma (SKCM) is the most life-threatening skin cancer and lacks early detection and effective treatment strategies. Many long noncoding RNAs are associated with the development of tumors and may serve as potential immunotherapeutic targets. In this study, microarray analysis was performed to screen for differentially expressed lncRNAs between SKCM and normal tissues, and SMG7-AS1 was identified as an upregulated lncRNA in SKCM. Subsequently, bioinformatic analysis revealed that dysregulation of SMG7-AS1 influences metastasis and immune infiltration. qRT-PCR of clinical samples demonstrated that the expression of SMG7-AS1 was higher in melanoma tissues. Flow cytometry showed that SMG7-AS1 plays a vital role in the cell cycle. Additionally, SMG7-AS1 was found to be associated with immunotherapy responses. To the best of our knowledge, this study is the first to report that SMG7-AS1 is associated with SKCM and may serve as a prognostic biomarker and predictor of immunotherapy responses in SKCM.

Extracellular vesicle-loaded hydrogels for tissue repair and regeneration.

Extracellular vesicles (EVs) are a collective term for nanoscale or microscale vesicles secreted by cells that play important biological roles. Mesenchymal stem cells are a class of cells with the potential for self-healing and multidirectional differentiation. In recent years, numerous studies have shown that EVs, especially those secreted by mesenchymal stem cells, can promote the repair and regeneration of various tissues and, thus, have significant potential in regenerative medicine. However, due to the rapid clearance capacity of the circulatory system, EVs are barely able to act persistently at specific sites for repair of target tissues. Hydrogels have good biocompatibility and loose and porous structural properties that allow them to serve as EV carriers, thereby prolonging the retention in certain specific areas and slowing the release of EVs. When EVs are needed to function at specific sites, the EV-loaded hydrogels can stand as an excellent approach. In this review, we first introduce the sources, roles, and extraction and characterization methods of EVs and describe their current application status. We then review the different types of hydrogels and discuss factors influencing their abilities to carry and release EVs. We summarize several strategies for loading EVs into hydrogels and characterizing EV-loaded hydrogels. Furthermore, we discuss application strategies for EV-loaded hydrogels and review their specific applications in tissue regeneration and repair. This article concludes with a summary of the current state of research on EV-loaded hydrogels and an outlook on future research directions, which we hope will provide promising ideas for researchers.

Emerging 3D bioprinting applications in plastic surgery.

Plastic surgery is a discipline that uses surgical methods or tissue transplantation to repair, reconstruct and beautify the defects and deformities of human tissues and organs. Three-dimensional (3D) bioprinting has gained widespread attention because it enables fine customization of the implants in the patient's surgical area preoperatively while avoiding some of the adverse reactions and complications of traditional surgical approaches. In this paper, we review the recent research advances in the application of 3D bioprinting in plastic surgery. We first introduce the printing process and basic principles of 3D bioprinting technology, revealing the advantages and disadvantages of different bioprinting technologies. Then, we describe the currently available bioprinting materials, and dissect the rationale for special dynamic 3D bioprinting (4D bioprinting) that is achieved by varying the combination strategy of bioprinting materials. Later, we focus on the viable clinical applications and effects of 3D bioprinting in plastic surgery. Finally, we summarize and discuss the challenges and prospects for the application of 3D bioprinting in plastic surgery. We believe that this review can contribute to further development of 3D bioprinting in plastic surgery and provide lessons for related research.

Exosomes from human adipose-derived mesenchymal stromal/stem cells accelerate angiogenesis in wound healing: implication of the EGR-1/lncRNA-SENCR/DKC1/VEGF-A axis.

Exosomes (Exos) extracted from human adipose mesenchymal stromal/stem cells (hAD-MSCs) have been reported as therapeutic tools for tissue repair, but how they regulate angiogenesis of endothelial cells remains unknown. In this study, hAD-MSCs were isolated, and early growth response factor-1, Smooth muscle and endothelial cell enriched migration/differentiation-associated long-noncoding RNA (lncRNA-SENCR), and vascular endothelial growth factor-A (VEGF-A) overexpression or knockdown was achieved. Exos extracted from hAD-MSCs (hADSC-Exos) were co-cultured with human umbilical vein endothelial cells (HUVECs) to detect the effects of EGR-1, lncRNA-SENCR, and VEGF-A on angiogenesis and the relationships between EGR-1, lncRNA-SENCR, Dyskerin pseudouridine synthase 1 (DKC1), and VEGF-A. An in vivo experiment verified the effect of hADSC-Exos on the wound healing process. hADSC-Exos substantially promoted the proliferation, migration, and angiogenesis of HUVECs, which could be reversed by short-hairpin RNA SENCR (shSENCR) transfection. hADSC-Exos had elevated expression of EGR-1, which bound to the lncRNA-SENCR promoter. The suppressive effect of Exo-shEGR1 on HUVECs was counteracted by SENCR overexpression. LncRNA-SENCR was shown to interact with DKC1. Overexpression of DKC1 or lncRNA-SENCR maintained stable VEGF-A expression. Overexpression of VEGF-A reversed the suppressive effect of shSENCR on HUVECs. Consistent results were obtained in mice in vivo. Overall, hADSC-Exo EGR-1 upregulates lncRNA-SENCR expression to activate the DKC1/VEGF-A axis, facilitating the wound-healing process by increasing angiogenesis.