Exosome/metformin-loaded self-healing conductive hydrogel rescues microvascular dysfunction and promotes chronic diabetic wound healing by inhibiting mitochondrial fission

Antibacterial betaine modified chitosan-based hydrogel with angiogenic property for photothermal enhanced diabetic wound repairing

Chronic diabetes wound repairing is still a huge challenge in clinical practice. High concentration of reactive oxygen species and vascular disfunction are the main factors hindering the recovery of diabetes wounds. This research grafted betaine onto chitosan (CSBT) to enhance the antibacterial property and the CSBT was cross-linked with PEO90 dialdehyde (PEO DA) to prepare hydrogel with Ca2+ loading to promote the coagulation. The polydopamine nanoparticles (PDA NPs) with photothermal property and antioxidant property was composited to the hydrogel and deferoxamine (DFO) was loaded to fabricate the multifunctional CBPCa/PDA/DFO hydrogel to promote vascular regeneration in combination with photothermal antibacterial performance for the diabetes wounds treatment. The CBPCa/PDA/DFO hydrogel showed good mechanical strength, injectability, anti-inflammatory property and coagulation performance. Furthermore, the antibacterial effect of chitosan based hydrogel was enhanced with near infrared (NIR) stimulated photothermal treatment. Combined with the photothermal effect and the angiogenic drug DFO release, the CBPCa/PDA/DFO hydrogel significantly enhanced vascular regeneration and reduced the inflammation in the in vivo wound repairing experiment. As a result, the CBPCa/PDA/DFO hydrogel may provide a promising therapeutic platform for diabetic trauma repairing.

Shikonin protects mitochondria through the NFAT5/AMPK pathway for the treatment of diabetic wounds

BACKGROUND

Shikonin is a natural remedy that is effective at treating diabetic wounds. NFAT5 is a potential therapeutic target for diabetes, and mitochondrial function is essential for wound healing. However, the relationship among Shikonin, NFAT5, and mitochondrial function has not been thoroughly studied. Here, we offer new perspectives on the advantages of shikonin for managing diabetes.

AIM

To assess the therapeutic mechanism of shikonin in diabetic wounds, its relationship with NFAT5, and its protection of mitochondrial function.

METHODS

Hypertonic cell and diabetic wound mouse models were established. NFAT5 expression was measured through western blotting and immunofluorescence, in vivo and in vitro. Mitochondrial function was evaluated using reactive oxygen species (ROS) detection and JC-1 and Calcein AM dyes. Mitochondrial structures were observed using transmission electron microscopy. The NFAT5/AMPK pathway was analyzed using a transfection vector and an inhibitor. The effect of shikonin on cells under hypertonic conditions via the NFAT5/AMPK pathway was assessed using western blotting.

RESULTS

Shikonin treatment preserved HaCaT cell viability, while significantly reducing cyclooxygenase-2 expression levels in a high-glucose environment (P < 0.05). Additionally, shikonin maintained mitochondrial morphology, enhanced membrane potential, reduced membrane permeability, and decreased ROS levels in HaCaT cells under hyperosmolar stress. Furthermore, shikonin promoted wound healing in diabetic mice (P < 0.05). Shikonin also inhibited NFAT5, in vivo and in vitro (P < 0.05). Shikonin treatment reduced NFAT5 expression levels, subsequently inhibiting AMPK expression in vitro (P < 0.05). Finally, shikonin inhibited several key downstream molecules of the NFAT5/AMPK pathway, including mammalian target of rapamycin, protein kinase B, nuclear factor kappa-light-chain-enhancer of activated B cells, and inducible nitric oxide synthase (P < 0.05).

CONCLUSION

Shikonin protects mitochondria via the NFAT5/AMPK-related pathway and enhances wound healing in diabetes.

Sandwich-Structured Nanofiber Dressings Containing MgB2 and Metformin Hydrochloride With ROS Scavenging and Antibacterial Properties for Wound Healing in Diabetic Infections

The treatment of chronic diabetic wounds is a major challenge due to oxidative stress, persistent hyperglycemia, and susceptibility to bacterial infection. In this study, multifunctional sandwich-structured nanofiber dressings (SNDs) are prepared via electrospinning. The SNDs consisted of an outer layer of hydrophobic polylactic acid (PLA) fibers encapsulating MgB2 nanosheets (MgB2 NSs), a middle layer of PLA and polyvinylpyrrolidone (PVP) fibers encapsulating the MgB2 NSs and metformin hydrochloride complex (MgB2-Met), and an inner layer of water-soluble PVP fibers encapsulating MgB2-Met. Because of their special sandwich structure, SNDs have high photothermal conversion efficiency (24.13%) and photothermal cycle performance. SNDs also exhibit a photothermal effect, bacteria-targeting effect of MgB2, electrostatic attraction ability of metformin hydrochloride (Met), and strong antibacterial activity against Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA). SNDs can eliminate intracellular reactive oxygen species (ROS) by regulating the hydrogen release from MgB2. In addition, SNDs have good biocompatibility, can effectively inhibit the inflammatory factor Interleukin-6 (IL-6), and promote granulation tissue formation, collagen deposition, and diabetic wound healing. These findings offer a promising approach for clinical treatment of diabetic wounds.

Wireless, Programmable, and Refillable Hydrogel Bioelectronics for Enhanced Diabetic Wound Healing

Diabetic wounds, characterized by complex pathogenesis and high infection rates, pose significant challenges in treatment due to prolonged recovery times and high recurrence rates, often leading to severe complications such as amputation and death. Traditional dry dressing treatments fail to address the unique microenvironment of diabetic wounds and tend to cause secondary damage due to frequent replacement. In this study, an electronic-embedding, drug-loading hydrogel bioelectronics is reported for accelerating diabetic wound healing using a combination of programmable pharmaceutical and electrostimulative approaches. Encapsulated in stretchable and biocompatible materials, this device is capable of multiple drug refilling and accelerated drug release modulated by on-board electronics. In vivo experiments on diabetic model rats confirm the device's effectiveness in promoting wound healing. This innovative approach implies the potential for improving diabetic wound management using a combination of physical, material, and pharmaceutical interventions.

Nanoparticle-Based Therapeutics for Enhanced Burn Wound Healing: A Comprehensive Review

Burn wounds pose intricate clinical challenges due to their severity and high risk of complications, demanding advanced therapeutic strategies beyond conventional treatments. This review discusses the application of nanoparticle-based therapies for optimizing burn wound healing. We explore the critical phases of burn wound healing, including inflammation, proliferation, and remodeling, while summarizing key nanoparticle-based strategies that influence these processes to optimize healing. Various nanoparticles, such as metal-based, polymer-based, and extracellular vesicles, are evaluated for their distinctive properties and mechanisms of action, including antimicrobial, anti-inflammatory, and regenerative effects. Future directions are highlighted, focusing on personalized therapies and the integration of sophisticated drug delivery systems, emphasizing the transformative potential of nanoparticles in enhancing burn wound treatment.

Synthesis and characterization of self-healable supramolecular hydrogel based on carboxymethyl cellulose for biomedical applications

Hydrogels have been widely used in biomedical fields including tissue engineering, drug delivery and cell delivery and 3D cell delivery due to abundant water content in their hydrophilic three-dimensional networks and having soft tissue similar to the human body. In recent years, supramolecular hydrogels (SHG) formed by the inclusion complex between polyethylene glycol (PEG) and macrocycles such as cyclodextrin (CD) have attracted much interest due to their excellent biocompatibility and great potential in biomedical. In this research, a carboxymethyl cellulose (CMC)-based graft copolymer was prepared by using acrylic acid (AA) and maleic anhydride functionalized β-CD (β-CD-MA) as comonomers and ammonium persulfate (APS) as initiator. Then, a self-healable supramolecular hydrogel was synthesized by formation of a host-guest inclusion complex between CMC-g-poly (AA-co-β-CD-MA) as host molecule and cytosine- and guanine-modified PEG as guest molecules. The prepared hydrogel was characterized by Scanning Electron Microscope (SEM), X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance spectroscopy (1H NMR). The thermal stability of hydrogel was also determined by thermal gravimetric (TGA) and differential scanning calorimetry (DSC) methods. In addition, the loading and release profiles of metformin hydrochloride (MH) drug as a model on hydrogel was investigated. The results indicated that the drug release from the hydrogel peaks around 360 min and aligns with the Ritger-Peppas model. The hydrogel's self-healing property was examined at ambient temperature and 37 °C. It showed 70 % healing in 1.5 h and completed recovery after 9 h.

Applications of plant-derived extracellular vesicles in medicine

Plant-derived extracellular vesicles (EVs) are promising therapeutic agents owing to their natural abundance, accessibility, and unique biological properties. This review provides a comprehensive exploration of the therapeutic potential of plant-derived EVs and emphasizes their anti-inflammatory, antimicrobial, and tumor-inhibitory effects. Here, we discussed the advancements in isolation and purification techniques, such as ultracentrifugation and size-exclusion chromatography, which are critical for maintaining the functional integrity of these nanovesicles. Next, we investigated the diverse administration routes of EVs and carefully weighed their respective advantages and challenges related to bioavailability and patient compliance. Moreover, we elucidated the multifaceted mechanisms of action of plant-derived EVs, including their roles in anti-inflammation, antioxidation, antitumor activity, and modulation of gut microbiota. We also discussed the impact of EVs on specific diseases such as cancer and inflammatory bowel disease, highlighting the importance of addressing current challenges related to production scalability, regulatory compliance, and immunogenicity. Finally, we proposed future research directions for optimizing EV extraction and developing targeted delivery systems. Through these efforts, we envision the seamless integration of plant-derived EVs into mainstream medicine, offering safe and potent therapeutic alternatives across various medical disciplines.

The Angiogenic Repertoire of Stem Cell Extracellular Vesicles: Demystifying the Molecular Underpinnings for Wound Healing Applications

Stem cells-derived extracellular vesicles (SC-EVs) have emerged as promising therapeutic agents for wound repair, recapitulating the biological effects of parent cells while mitigating immunogenic and tumorigenic risks. These EVs orchestrate wound healing processes, notably through modulating angiogenesis-a critical event in tissue revascularization and regeneration. This study provides a comprehensive overview of the multifaceted mechanisms underpinning the pro-angiogenic capacity of EVs from various stem cell sources within the wound microenvironment. By elucidating the molecular intricacies governing their angiogenic prowess, we aim to unravel the mechanistic repertoire underlying their remarkable potential to accelerate wound healing. Additionally, methods to enhance the angiogenic effects of SC-EVs, current limitations, and future perspectives are highlighted, emphasizing the significant potential of this rapidly advancing field in revolutionizing wound healing strategies.

Netrin-1 co-cross-linked hydrogel accelerates diabetic wound healing in situ by modulating macrophage heterogeneity and promoting angiogenesis

Diabetic wounds, characterized by prolonged inflammation and impaired vascularization, are a serious complication of diabetes. This study aimed to design a gelatin methacrylate (GelMA) hydrogel for the sustained release of netrin-1 and evaluate its potential as a scaffold to promote diabetic wound healing. The results showed that netrin-1 was highly expressed during the inflammation and proliferation phases of normal wounds, whereas it synchronously exhibited aberrantly low expression in diabetic wounds. Neutralization of netrin-1 inhibited normal wound healing, and the topical application of netrin-1 accelerated diabetic wound healing. Mechanistic studies demonstrated that netrin-1 regulated macrophage heterogeneity via the A2bR/STAT/PPARγ signaling pathway and promoted the function of endothelial cells, thus accelerating diabetic wound healing. These data suggest that netrin-1 is a potential therapeutic target for diabetic wounds.

A cuttlefish ink nanoparticle-reinforced biopolymer hydrogel with robust adhesive and immunomodulatory features for treating oral ulcers in diabetes

Oral ulcers can be managed using a variety of biomaterials that deliver drugs or cytokines. However, many patients experience minimal benefits from certain medical treatments because of poor compliance, short retention times in the oral cavity, and inadequate drug efficacy. Herein, we present a novel hydrogel patch (SCE2) composed of a biopolymer matrix (featuring ultraviolet-triggered adhesion properties) loaded with cuttlefish ink nanoparticles (possessing pro-healing functions). Applying a straightforward local method initiates the formation of a hydrogel barrier that adheres to mucosal injuries under the influence of ultraviolet light. SCE2 then demonstrates exceptional capabilities for near-infrared photothermal sterilization and neutralization of reactive oxygen species. These properties contribute to the elimination of bacteria and the management of the oxidation process, thus accelerating the healing phase's progression from inflammation to proliferation. In studies involving diabetic rats with oral ulcers, the SCE2 adhesive patch significantly quickens recovery by altering the inflamed state of the injured area, facilitating rapid re-epithelialization, and fostering angiogenesis. In conclusion, this light-sensitive hydrogel patch offers a promising path to expedited wound healing, potentially transforming treatment strategies for clinical oral ulcers.

Promoting the healing of infected diabetic wound by nanozyme-containing hydrogel with anti-bacterial inflammation suppressing, ROS-scavenging and oxygen-generating properties

Bacterial infections already pose a significant threat to skin wounds, especially in diabetic patients who have difficulty healing wounds. However, wound or bacterial infections are known to produce excess reactive oxygen species (ROS), and hypoxia may further hinder wound healing and the development of chronic wounds. In this study, a multifunctional hydrogel for ROS scavenging and bacterial inhibition was developed by cross-linking polyvinyl alcohol (PVA) and sodium alginate (SA) with graphene oxide (GO) loaded with silver-platinum hybrid nanoparticles (GO@Ag-Pt). The PVA/SA hydrogel loaded with GO@Ag-Pt exhibited the ability to scavenge different types of ROS, generate O2, and kill a broad spectrum of bacteria in vitro. The silver-platinum hybrid nanoparticles significantly increased the antibacterial ability against Escherichia coli and Staphylococcus aureus compared with silver nanoparticles (AgNps). GO@Ag-Pt loaded hydrogel was effective in treating infections caused by S.aureus, thereby significantly promoting wound healing during the inflammatory phase. Hydrogel therapy significantly reduced the level of ROS and alleviated inflammation levels. Notably, our ROS-scavenging, antibacterial hydrogels can be used to effectively treat various types of wounds, including difficult-to-heal diabetic wounds with bacterial infections. Thus, this study proposes an effective strategy for various chronic wound healing based on ROS clearance and bacteriostatic hydrogels.

Metformin Treatment of Macrophages Increases Microvessel Growth in Three-Dimensional Hydrogel Coculture

The global population is aging rapidly, posing unprecedented challenges to health care systems. This study investigates the often-overlooked role of macrophages in microvascular dysfunction associated with aging. We use a three-dimensional in vitro hydrogel model to assess the effects of both age and metformin, an anti-aging therapeutic, on macrophage interactions with microvasculature. Metformin's broad cellular impact is a subject of significant interest, yet its precise mechanisms remain unclear. Our research reveals that metformin treatment enhances genetic pathways associated with macrophage-mediated support of angiogenesis, resulting in increased microvessel density. Of importance, monocyte chemoattractant protein-1 expression is upregulated with metformin treatment and positively correlated with microvascular volume, shedding light on a potential mechanism for metformin's promotion of macrophage support of vasculogenesis. This work not only uncovers metformin's impact on human macrophages but also supports its potential as an antiaging therapeutic, offering new avenues for combating age-related diseases.

Adipose-Derived Stem Cell Exosomes Facilitate Diabetic Wound Healing: Mechanisms and Potential Applications

Wound healing in diabetic patients is frequently hampered. Adipose-derived stem cell exosomes (ADSC-eoxs), serving as a crucial mode of intercellular communication, exhibit promising therapeutic roles in facilitating wound healing. This review aims to comprehensively outline the molecular mechanisms through which ADSC-eoxs enhance diabetic wound healing. We emphasize the biologically active molecules released by these exosomes and their involvement in signaling pathways associated with inflammation modulation, cellular proliferation, vascular neogenesis, and other pertinent processes. Additionally, the clinical application prospects of the reported ADSC-eoxs are also deliberated. A thorough understanding of these molecular mechanisms and potential applications is anticipated to furnish a theoretical groundwork for combating diabetic wound healing.

Recent advances in the use of extracellular vesicles from adipose-derived stem cells for regenerative medical therapeutics

Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells (MSCs) isolated from adipose tissue. They possess remarkable properties, including multipotency, self-renewal, and easy clinical availability. ADSCs are also capable of promoting tissue regeneration through the secretion of various cytokines, factors, and extracellular vesicles (EVs). ADSC-derived EVs (ADSC-EVs) act as intercellular signaling mediators that encapsulate a range of biomolecules. These EVs have been found to mediate the therapeutic activities of donor cells by promoting the proliferation and migration of effector cells, facilitating angiogenesis, modulating immunity, and performing other specific functions in different tissues. Compared to the donor cells themselves, ADSC-EVs offer advantages such as fewer safety concerns and more convenient transportation and storage for clinical application. As a result, these EVs have received significant attention as cell-free therapeutic agents with potential future application in regenerative medicine. In this review, we focus on recent research progress regarding regenerative medical use of ADSC-EVs across various medical conditions, including wound healing, chronic limb ischemia, angiogenesis, myocardial infarction, diabetic nephropathy, fat graft survival, bone regeneration, cartilage regeneration, tendinopathy and tendon healing, peripheral nerve regeneration, and acute lung injury, among others. We also discuss the underlying mechanisms responsible for inducing these therapeutic effects. We believe that deciphering the biological properties, therapeutic effects, and underlying mechanisms associated with ADSC-EVs will provide a foundation for developing a novel therapeutic approach in regenerative medicine.

Ferrocene-Based Antioxidant Self-Healing Hydrogel via the Biginelli Reaction for Wound Healing

The development of antioxidant wound dressings to remove excessive free radicals around wounds is essential for wound healing. In this study, we developed an efficient strategy to prepare antioxidant self-healing hydrogels as wound dressings by combining multicomponent reactions (MCRs) and postpolymerization modification. A polymer containing ferrocene and phenylboronic acid groups was developed via the Biginelli reaction, followed by efficient modification. This polymer is antioxidant due to its ferrocene moieties and can rapidly cross-link poly(vinyl alcohol) to realize an antioxidant self-healing hydrogel through dynamic borate ester linkages. This hydrogel has low cytotoxicity and is biocompatible. In in vivo experiments, this hydrogel is superior to existing clinical dressings in promoting wound healing. This study demonstrates the value of the Biginelli reaction in exploring biomaterials, potentially offering insights into the design of other multifunctional polymers and related materials using different MCRs.

A Multifunctional Hydrogel Fabricated by Direct Self-Assembly of Natural Herbal Small Molecule Mangiferin for Treating Diabetic Wounds

Clinical studies have continually referred to the involvement of drug carrier having dramatic negative influences on the biocompatibility, biodegradability, and loading efficacy of hydrogel. To overcome this deficiency, researchers have proposed to directly self-assemble natural herbal small molecules into a hydrogel without any structural modification. However, it is still a formidable challenge due to the high requirements on the structure of natural molecules, leading to a rarity of this type of hydrogel. Mangiferin (MF) is a natural polyphenol of C-glucoside xanthone with various positive health benefits, including the treatment of diabetic wounds, but its poor hydrosolubility and low bioavailability significantly restrict the clinical application. Inspired by these, with heating/cooling treatment, a carrier-free hydrogel (MF-gel) is developed by assembling the natural herbal molecule mangiferin, which is mainly governed through hydrogen bonds and intermolecular π-π stacking interactions. The as-prepared hydrogel has injectable and self-healing properties and shows excellent biocompatibility, continuous release ability, and reversible stimuli-responsive performances. All of the superiorities enable the MF-based hydrogel to serve as a potential wound dressing for treating diabetic wounds, which was further confirmed by both the vitro and vivo studies. In vitro, the MF-gel could promote the migration of healing-related cells from peripheral as well as the angiogenesis and displays the capacity of mediating inflammation response by scavenging the intracellular ROS. In vivo, the MF-gel accelerates wound contraction and healing via inflammatory adjustment, collagen deposition, and angiogenesis. This study provides a facile and effective method for diabetic wound management and emphasizes the direct self-assembly hydrogel from natural herbal small molecule.

Advancing Tissue Damage Repair in Geriatric Diseases: Prospects of Combining Stem Cell-Derived Exosomes with Hydrogels

Geriatric diseases are a group of diseases with unique characteristics related to senility. With the rising trend of global aging, senile diseases now mainly include endocrine, cardiovascular, neurodegenerative, skeletal, and muscular diseases and cancer. Compared with younger populations, the structure and function of various cells, tissues and organs in the body of the elderly undergo a decline as they age, rendering them more susceptible to external factors and diseases, leading to serious tissue damage. Tissue damage presents a significant obstacle to the overall health and well-being of older adults, exerting a profound impact on their quality of life. Moreover, this phenomenon places an immense burden on families, society, and the healthcare system.In recent years, stem cell-derived exosomes have become a hot topic in tissue repair research. The combination of these exosomes with biomaterials allows for the preservation of their biological activity, leading to a significant improvement in their therapeutic efficacy. Among the numerous biomaterial options available, hydrogels stand out as promising candidates for loading exosomes, owing to their exceptional properties. Due to the lack of a comprehensive review on the subject matter, this review comprehensively summarizes the application and progress of combining stem cell-derived exosomes and hydrogels in promoting tissue damage repair in geriatric diseases. In addition, the challenges encountered in the field and potential prospects are presented for future advancements.

The Immunomodulatory effect of exosomes in diabetes: a novel and attractive therapeutic tool in diabetes therapy

Exosomes carry proteins, metabolites, nucleic acids and lipids from their parent cell of origin. They are derived from cells through exocytosis, are ingested by target cells, and can transfer biological signals between local or distant cells. Therefore, exosomes are often modified in reaction to pathological processes, including infection, cancer, cardiovascular diseases and in response to metabolic perturbations such as obesity and diabetes, all of which involve a significant inflammatory aspect. Here, we discuss how immune cell-derived exosomes origin from neutrophils, T lymphocytes, macrophages impact on the immune reprogramming of diabetes and the associated complications. Besides, exosomes derived from stem cells and their immunomodulatory properties and anti-inflammation effect in diabetes are also reviewed. Moreover, As an important addition to previous reviews, we describes promising directions involving engineered exosomes as well as current challenges of clinical applications in diabetic therapy. Further research on exosomes will explore their potential in translational medicine and provide new avenues for the development of effective clinical diagnostics and therapeutic strategies for immunoregulation of diabetes.

In Vivo Wound-Healing Efficacy of Insulin-Loaded Strontium-Cross-Linked Alginate-Based Hydrogels in Diabetic Rats

The wound-healing effect of insulin is well studied and reported. However, prolonged topical application of insulin without compromising its biological activity is still a challenge. In this study, the effect of topically delivered insulin on promoting wound healing in diabetic animals was evaluated. Alginate diamine PEG-g-poly(PEGMA) (ADPM2S2) was the material used for the topical delivery of insulin. ADPM2S2 hydrogels release insulin and strontium ions, and they synergistically act to regulate different phases of wound healing. Insulin was released from the ADPM2S2 hydrogel for a period of 48 h, maintaining its structural stability and biological activity. In vitro studies were performed under high-glucose conditions to evaluate the wound-healing potential of insulin. Insulin-loaded ADPM2S2 hydrogels showed significant improvement in cell migration, proliferation, and collagen deposition, compared to control cells under high-glucose conditions. Immunostaining studies in L929 cells showed a reduction in phospho Akt expression under high-glucose conditions, and in the presence of insulin, the expression increased. The gene expression studies revealed that insulin plays an important role in regulating the inflammatory phase and macrophage polarization, which favors accelerated wound closure. In vivo experiments in diabetic rat excision wounds treated with insulin-loaded ADPM2S2 showed 95% wound closure within 14 days compared with 82% in control groups. Thus, both the in vitro and in vivo results signify the therapeutic potential of topically delivered insulin in wound management under high-glucose conditions.

Advancements and Challenges in Self-Healing Hydrogels for Wound Care

This manuscript explores self-healing hydrogels as innovative solutions for diverse wound management challenges. Addressing antibiotic resistance and tailored wound care, these hydrogels exhibit promising outcomes, including accelerated wound closure and tissue regeneration. Advancements in multifunctional hydrogels with controlled drug release, antimicrobial properties, and real-time wound assessment capabilities signal a significant leap toward patient-centered treatments. However, challenges such as scalability, long-term safety evaluation, and variability in clinical outcomes persist. Future directions emphasize personalized medicine, manufacturing innovation, rigorous evaluation through clinical trials, and interdisciplinary collaboration. This manuscript features the ongoing pursuit of effective, adaptable, and comprehensive wound care solutions to transform medical treatments and improve patient outcomes.

Conductive hydrogels based on tragacanth and silk fibroin containing dopamine functionalized carboxyl-capped aniline pentamer: Merging hemostasis, antibacterial, and anti-oxidant properties into a multifunctional hydrogel for burn wound healing

Hydrogels possessing both conductive characteristics and notable antibacterial and antioxidant properties hold considerable significance within the realm of wound healing and recovery. The object of current study is the development of conductive hydrogels with antibacterial and antioxidant properties, emphasizing their potential for effective wound healing, especially in treating third-degree burns. For this purpose, various conductive hydrogels are developed based on tragacanth and silk fibroin, with variable dopamine functionalized carboxyl-capped aniline pentamer (CAP@DA). The FTIR analysis confirms that the CAP powder was successfully synthesized and modified with DA. The results show that the incorporation of CAP@DA into hydrogels can increase the porosity and swellability of the hydrogels. Additionally, the mechanical and viscoelastic properties of the hydrogels are also improved. The release of vancomycin from the hydrogels is sustained over time, and the hydrogels are effective in inhibiting the growth of Methicillin-resistant Staphylococcus aureus (MRSA). In vitro cell studies of the hydrogels show that all hydrogels are biocompatible and support cell attachment. The hydrogels' tissue adhesiveness yielded a satisfactory hemostatic outcome in a rat-liver injury model. The third-degree burn was created on the dorsal back paravertebral region of the rats and then grafted with hydrogels. The burn was monitored for 3, 7, and 14 days to evaluate the efficacy of the hydrogel in promoting wound healing. The hydrogels revealed treatment effect, resulting in enhancements in wound closure, dermal collagen matrix production, new blood formation, and anti-inflammatory properties. Better results were obtained for hydrogel with increasing CAP@DA. In summary, the multifunctional conducive hydrogel, featuring potent antibacterial properties, markedly facilitated the wound regeneration process.

Extracellular Vesicles and Hydrogels: An Innovative Approach to Tissue Regeneration

Extracellular vesicles have emerged as promising tools in regenerative medicine due to their inherent ability to facilitate intercellular communication and modulate cellular functions. These nanosized vesicles transport bioactive molecules, such as proteins, lipids, and nucleic acids, which can affect the behavior of recipient cells and promote tissue regeneration. However, the therapeutic application of these vesicles is frequently constrained by their rapid clearance from the body and inability to maintain a sustained presence at the injury site. In order to overcome these obstacles, hydrogels have been used as extracellular vesicle delivery vehicles, providing a localized and controlled release system that improves their therapeutic efficacy. This Review will examine the role of extracellular vesicle-loaded hydrogels in tissue regeneration, discussing potential applications, current challenges, and future directions. We will investigate the origins, composition, and characterization techniques of extracellular vesicles, focusing on recent advances in exosome profiling and the role of machine learning in this field. In addition, we will investigate the properties of hydrogels that make them ideal extracellular vesicle carriers. Recent studies utilizing this combination for tissue regeneration will be highlighted, providing a comprehensive overview of the current research landscape and potential future directions.

Hydrogel-mediated extracellular vesicles for enhanced wound healing: the latest progress, and their prospects for 3D bioprinting

Extracellular vesicles have shown promising tissue recovery-promoting effects, making them increasingly sought-after for their therapeutic potential in wound treatment. However, traditional extracellular vesicle applications suffer from limitations such as rapid degradation and short maintenance during wound administration. To address these challenges, a growing body of research highlights the role of hydrogels as effective carriers for sustained extracellular vesicle release, thereby facilitating wound healing. The combination of extracellular vesicles with hydrogels and the development of 3D bioprinting create composite hydrogel systems boasting excellent mechanical properties and biological activity, presenting a novel approach to wound healing and skin dressing. This comprehensive review explores the remarkable mechanical properties of hydrogels, specifically suited for loading extracellular vesicles. We delve into the diverse sources of extracellular vesicles and hydrogels, analyzing their integration within composite hydrogel formulations for wound treatment. Different composite methods as well as 3D bioprinting, adapted to varying conditions and construction strategies, are examined for their roles in promoting wound healing. The results highlight the potential of extracellular vesicle-laden hydrogels as advanced therapeutic tools in the field of wound treatment, offering both mechanical support and bioactive functions. By providing an in-depth examination of the various roles that these composite hydrogels can play in wound healing, this review sheds light on the promising directions for further research and development. Finally, we address the challenges associated with the application of composite hydrogels, along with emerging trends of 3D bioprinting in this domain. The discussion covers issues such as scalability, regulatory considerations, and the translation of this technology into practical clinical settings. In conclusion, this review underlines the significant contributions of hydrogel-mediated extracellular vesicle therapy to the field of 3D bioprinting and wound healing and tissue regeneration. It serves as a valuable resource for researchers and practitioners alike, fostering a deeper understanding of the potential benefits, applications, and challenges involved in utilizing composite hydrogels for wound treatment.

Antibacterial microneedle patch releases oxygen to enhance diabetic wound healing

Cell growth and metabolism require an adequate supply of oxygen. However, obtaining sufficient oxygen from the blood circulating around diabetic wounds is challenging. Nevertheless, achieving a continuous and stable oxygen supply is required for these wounds to heal. Hence, in this study, we report a novel antibacterial oxygen-producing silk fibroin methacryloyl hydrogel microneedle (MN) patch comprising tips encapsulated with calcium peroxide and catalase and a base coated with antibacterial Ag nanoparticles (AgNPs). The tip of the MN patch continuously releases oxygen and inhibits the production of reactive oxygen species. This accelerates diabetic wound healing by promoting cellular accretion and migration, macrophage M2 polarization, and angiogenesis. The AgNPs at the base of the MN patch effectively combat microbial infection, further facilitating wound repair. These findings suggest that using this multifunctional oxygen-producing MN patch may be a promising strategy for diabetic wound healing in clinical settings.

Exosomes from adipose-derived stem cells restore fibroblast function and accelerate diabetic wound healing

Background

Diabetes is common yet challenging chronic disease, that affects a wide range of people around the world. Complex cellular environments around diabetic wounds tend to damage the function of effector cells, including vascular endothelial cells (VECs), fibroblasts and epithelial cells. This study aims to analyze the differences between diabetic wounds and normal skin as well as whether adipose-derived stem cell (ADSC) exosome could promote healing of diabetic wound.

Methods

Human diabetic wounds and normal skin were collected and stained with HE, Masson, CD31 and 8-hydroxy-2 deoxyguanosine immunohistochemical staining. RNA-seq data were collected for further bioinformatics analysis. ADSC exosomes were isolated and identified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blotting. The effect of ADSC exosomes on diabetic wound healing was assessed on full thickness wounds in mice. To further verify the regulative impact of ADSCs exosomes in high glucose treated fibroblasts, we isolated fibroblasts from normal skin tissue and measured the cell viability, apoptosis rate, proliferation and migration of fibroblasts. In addition, collagen formation and fibrosis-related molecules were also detected. To further disclose the mechanism of ADSC exosomes on the function of high glucose treated fibroblasts, we detected the expression of apoptosis related molecules including BCL2, Bax, and cleaved caspase-3.

Results

Histological observation indicated that perilesional skin tissues from diabetic patients showed structural disorder, less collagen disposition and increased injury compared with normal skin. Bioinformatics analysis showed that the levels of inflammatory and collagen synthesis related molecules, as well as oxidative stress and apoptosis related molecules, were significantly changed. Furthermore, we found that ADSC exosomes could not only speed up diabetic wound healing, but could also improve healing quality. ADSC exosomes restored high glucose induced damage to cell viability, migration and proliferation activity, as well as fibrosis-related molecules such as SMA, collagen 1 and collagen 3. In addition, we verified that ADSC exosomes downregulated high glucose induced increased apoptosis rate in fibroblast and the protein expression of Bax as well as cleaved caspases 3.

Conclusions

This study indicated that ADSC exosomes alleviated high glucose induced damage to fibroblasts and accelerate diabetic wound healing by inhibiting Bax/caspase 3.

A novel antibacterial hydrogel based on thiolated ovalbumin/gelatin with silver ions to promote wound healing in mice

Hydrogels could be used as wound dressings, but most protein-based hydrogels lack anti-bacterial effects. Here, we successfully prepared a silver ion cross-linked thiolated protein hydrogel (thiolated Ovalbumin and Gelatin, O3G7). The wound photographs showed that the healing rate (96.23 %) of hydrogel-treated mice was higher than the control group. Meanwhile, the hydrogel increased the granulation tissue's total protein content. Furthermore, it significantly increased the collagen content, consistent with the results of Masson's trichrome (MT) staining and immunohistochemical analysis of type I collagen (ColI). The results of hematoxylin and eosin (H&E) staining showed the growth and proliferation of inflammatory cells, granulation tissue, fibroblasts, blood vessels and hair follicles in acute wounds. O3G7 hydrogel had fewer inflammatory cells and more neovascularization, and hair follicle tissue and intact epidermis could be observed. The results of immunofluorescence and immunohistochemistry showed that the O3G7 group reduced the expression of tumor necrosis factor (TNF)-α (56.87 % of the control group) and upregulated the expression of transforming growth factor (TGF)-β (1.29 times of the control group). These results suggest that O3G7 hydrogel significantly affects the healing of acute wounds. This study demonstrates that hydrogels prepared from food-derived proteins will be promising and bio-safe candidates in bioengineering.

Fabrication of an Adhesive Small Intestinal Submucosa Acellular Matrix Hydrogel for Accelerating Diabetic Wound Healing

The treatment of diabetic skin defects comes with enormous challenges in the clinic due to the disordered metabolic microenvironment. In this study, we therefore designed a novel composite hydrogel (SISAM@HN) with bioactive factors and tissue adhesive properties for accelerating chronic diabetic wound healing. Hyaluronic acid (HA) modified by N-(2-aminoethyl)-4-(4-(hydroxymethyl)-2-methoxy-5-nitrosophenoxy) butanamide (NB) held the phototriggering tissue adhesive capacity. Decellularized small intestinal submucosa (SIS) was degreased and digested to form the acellular matrix, which facilitated bioactive factor release. The results of the burst pressure test demonstrated that the in situ formed hydrogel possessed a tissue adhesive property. In vitro experiments, based on bone marrow stromal cells, revealed that the SIS acellular matrix-containing hydrogel contributed to promoting cell proliferation. In vivo, a diabetic mouse model was created and used to evaluate the tissue regeneration function of the obtained hydrogel, and our results showed that the synthesized hydrogel could assist collagen deposition, attenuate inflammation, and foster vascular growth during the wound healing process. Overall, the SIS acellular matrix-containing HA hydrogel was able to adhere to the wound sites, promote cell proliferation, and facilitate angiogenesis, which would be a promising biomaterial for wound dressing in clinical therapy of diabetic skin defects.

Extracellular vesicle biopotentiated hydrogels for diabetic wound healing: The art of living nanomaterials combined with soft scaffolds

Diabetic wounds (DWs) pose a major challenge for the public health system owing to their high incidence, complex pathogenesis, and long recovery time; thus, there is an urgent need to develop innovative therapies to accelerate the healing process of diabetic wounds. As natural nanovesicles, extracellular vesicles (EVs) are rich in sources with low immunogenicity and abundant nutritive molecules and exert potent therapeutic effects on diabetic wound healing. To avoid the rapid removal of EVs, a suitable delivery system is required for their controlled release. Owing to the advantages of high porosity, good biocompatibility, and adjustable physical and chemical properties of hydrogels, EV biopotentiated hydrogels can aid in achieving precise and favorable therapy against diabetic wounds. This review highlights the different design strategies, therapeutic effects, and mechanisms of EV biopotentiated hydrogels. We also discussed the future challenges and opportunities of using EV biopotentiated hydrogels for diabetic wound healing.

Chitosan/silk fibroin nanofibers-based hierarchical sponges accelerate infected diabetic wound healing via a HClO self-producing cascade catalytic reaction

The diabetic chronic wound healing is extremely restricted by issues such as hyperglycemia, excessive exudate and reactive oxygen species (ROS), and bacterial infection, causing significant disability and fatality rate. Herein, the chitosan/silk fibroin nanofibers-based hierarchical 3D sponge (CSSF-P/AuGCs) with effective exudate transfer and wound microenvironment modulation are produced by integrating cascade reactor (AuGC) into sponge substrates with parallel-arranged microchannels. When applied to diabetic wounds, the uniformly parallel-arranged microchannels endow CSSF-P/AuGCs with exceptional exudate absorption capacity, keeping the wound clean and moist; additionally, AuGCs efficiently depletes glucose in wounds to generate H2O2, which is then converted into HClO via cascade catalytic reaction to eliminate bacterial infection and reduce inflammation. Experiments in vitro demonstrated that the antibacterial activity of CSSF-P/AuGCs against S. aureus and E. coli was 92.7 and 94.27 %, respectively. Experiments on animals indicated that CSSF-P/AuGC could cure wounds in 11 days, displaying superior wound-healing abilities when compared to the commercial medication Tegaderm™. This versatile CSSF-P/AuGCs dressing may be an attractive choice for expediting diabetic wound healing with little cytotoxicity, providing a novel therapeutic method for establishing a favorable pathological microenvironment for tissue repair.

Hypoxic Microenvironment Reconstruction with Synergistic Biofunctional Ions Promotes Diabetic Wound Healing

Chronic hypoxia and ischemia make diabetic wounds non-healing. Cellular functions of diabetic chronic wounds are inhibited under a pathological environment. Therefore, this work develops a composite hydrogel system to promote diabetic wound healing. The composite hydrogel system consists of ε-poly-lysine (EPL), calcium peroxide (CP), and borosilicate glass (BG). The hydrogel supplies continuous dissolved oxygen molecules to the wound that can penetrate the skin tissue to restore normal cellular function and promote vascular regeneration. Biofunctional ions released from BGs can recruit more macrophages through neovascularization and modulate macrophage phenotypic transformation. Combining oxygen-mediated vascular regeneration and ion-mediated inflammatory regulation significantly accelerated diabetic wound healing. These findings indicate that this composite hydrogel system holds promise as a novel tissue engineering material.

Multifunctional and theranostic hydrogels for wound healing acceleration: An emphasis on diabetic-related chronic wounds

Hydrogels represent intricate three-dimensional polymeric structures, renowned for their compatibility with living systems and their ability to naturally degrade. These networks stand as promising and viable foundations for a range of biomedical uses. The practical feasibility of employing hydrogels in clinical trials has been well-demonstrated. Among the prevalent biomedical uses of hydrogels, a significant application arises in the context of wound healing. This intricate progression involves distinct phases of inflammation, proliferation, and remodeling, often triggered by trauma, skin injuries, and various diseases. Metabolic conditions like diabetes have the potential to give rise to persistent wounds, leading to delayed healing processes. This current review consolidates a collection of experiments focused on the utilization of hydrogels to expedite the recovery of wounds. Hydrogels have the capacity to improve the inflammatory conditions at the wound site, and they achieve this by diminishing levels of reactive oxygen species (ROS), thereby exhibiting antioxidant effects. Hydrogels have the potential to enhance the growth of fibroblasts and keratinocytes at the wound site. They also possess the capability to inhibit both Gram-positive and Gram-negative bacteria, effectively managing wounds infected by drug-resistant bacteria. Hydrogels can trigger angiogenesis and neovascularization processes, while also promoting the M2 polarization of macrophages, which in turn mitigates inflammation at the wound site. Intelligent and versatile hydrogels, encompassing features such as pH sensitivity, reactivity to reactive oxygen species (ROS), and responsiveness to light and temperature, have proven advantageous in expediting wound healing. Furthermore, hydrogels synthesized using environmentally friendly methods, characterized by high levels of biocompatibility and biodegradability, hold the potential for enhancing the wound healing process. Hydrogels can facilitate the controlled discharge of bioactive substances. More recently, there has been progress in the creation of conductive hydrogels, which, when subjected to electrical stimulation, contribute to the enhancement of wound healing. Diabetes mellitus, a metabolic disorder, leads to a slowdown in the wound healing process, often resulting in the formation of persistent wounds. Hydrogels have the capability to expedite the healing of diabetic wounds, facilitating the transition from the inflammatory phase to the proliferative stage. The current review sheds light on the biological functionalities of hydrogels, encompassing their role in modulating diverse mechanisms and cell types, including inflammation, oxidative stress, macrophages, and bacteriology. Additionally, this review emphasizes the significance of smart hydrogels with responsiveness to external stimuli, as well as conductive hydrogels for promoting wound healing. Lastly, the discussion delves into the advancement of environmentally friendly hydrogels with high biocompatibility, aimed at accelerating the wound healing process.

Silver Nanoparticles and Graphene Oxide Complex as an Anti-Inflammatory Biocompatible Liquid Nano-Dressing for Skin Infected with Staphylococcus aureus

Background

Bacterial skin infections, including Staphylococcus aureus, are a powerful and still not fully resolved problem. The aim of this research was to determine the possibility of using a complex of graphene oxide (GO) encrusted with silver nanoparticles as an effective antibacterial agent against S. aureus and to assess its pro-inflammatory properties.

Methods

The tests were carried out in vitro on EpiDerm™ Skin, an artificial skin model (MatTek in vitro Life Science Laboratories, Slovak Republic), and the fibroblast cell line (HFF-2 from ATCC, USA). Both models were infected with S. aureus bacteria (ATCC 25923) and then treated with antibiotics or our experimental factors: silver nanoparticles (AgNPs, Nano-koloid, Poland), graphene oxide (GO, NanoPoz, Poland), and complex AgNP-GO (hydrocolloid created by self-assembly).

Results

The antibacterial effectiveness of the AgNP-GO complex was equivalent to that of the antibiotic. In addition, an increase in the level of pro-inflammatory cytokines was observed under the influence of antibiotic administration, in contrast to the effect of AgNP-GO, which showed very limited pro-inflammatory activity.

Conclusion

Hydrocolloid of the AgNP-GO complex, administered in the form of a liquid dressing, may act as an antibacterial agent and also reduce inflammation induced by S. aureus infection.

Injectable Antiswelling and High-Strength Bioactive Hydrogels with a Wet Adhesion and Rapid Gelling Process to Promote Sutureless Wound Closure and Scar-free Repair of Infectious Wounds

Developing injectable antiswelling and high-strength bioactive hydrogels with wet tissue adhesiveness and a rapid gelling process to meet the requirements for rapid hemostasis, sutureless wound closure, and scar-free repair of infected skin wounds continues to have ongoing challenges. Herein, injectable, antibacterial, and antioxidant hydrogel adhesives based on poly(citric acid-co-polyethylene glycol)-g-dopamine and amino-terminated Pluronic F127 (APF) micelles loaded with astragaloside IV (AS) are prepared. The H2O2/horseradish peroxidase (HRP) system is used to cause cross-linking of the hydrogel network through oxidative coupling between catechol groups and chemical cross-linking between the catechol group and the amino group. The hydrogels exhibit a rapid gelling process, high mechanical strength, an antiswelling effect, good antioxidant property, H2O2 release behavior, and degradability. In addition, the hydrogels present good wet tissue adhesiveness, high bursting pressure, excellent antibacterial activity, long-term sustained release of AS, and good biocompatibility. The hydrogels perform good hemostasis on mouse liver, rat liver, and rabbit femoral vein bleeding models and achieve much better closure and healing of skin incisions than biomedical glue and surgical sutures. Furthermore, the hydrogel dressing significantly improved the scar-free repair of MRSA-infected full thickness skin defect wounds by modulating inflammation, regulating the ratio of collagen I/III, and improving the vascularization and granulation tissue formation. Thus, AS-loaded hydrogels show huge potential as multifunctional dressings for in vivo hemostasis, sutureless wound closure, and scar-free repair of infected skin wounds.

Multiple Bio-Actives Loaded Gellan Gum Microfibers from Microfluidics for Wound Healing

Wound healing, known as a fundamental healthcare issue worldwide, has been attracting great attention from researchers. Here, novel bioactive gellan gum microfibers loaded with antibacterial peptides (ABPs) and vascular endothelial growth factor (VEGF) are proposed for wound healing by using microfluidic spinning. Benefitting from the high controllability of microfluidics, bioactive microfibers with uniform morphologies are obtained. The loaded ABPs are demonstrated to effectively act on bacteria at the wound site, reducing the risk of bacterial infection. Besides, sustained release of VEGF from microfibers helps to accelerate angiogenesis and further promote wound healing. The practical value of woven bioactive microfibers is demonstrated via animal experiments, where the wound healing process is greatly facilitated because of the excellent circulation of air and nutritious substances. Featured with the above properties, it is believed that the novel bioactive gellan gum microfibers would have a remarkable effect in the field of biomedical application, especially in promoting wound healing.

The physiological phenomenon and regulation of macrophage polarization in diabetic wound

Macrophages play a crucial role in regulating wound healing, as they undergo a transition from the proinflammatory M1 phenotype to the proliferative M2 phenotype, ultimately contributing to a favorable outcome. However, in hyperglycemic and hyper-reactive oxygen species environments, the polarization of macrophages becomes dysregulated, hindering the transition from the inflammatory to proliferative phase and consequently delaying the wound healing process. Consequently, regulating macrophage polarization is often regarded as a potential target for the treatment of diabetic wounds. The role of macrophages in wound healing and the changes in macrophages in diabetic conditions were discussed in this review. After that, we provide a discussion of recent therapeutic strategies for diabetic wounds that utilize macrophage polarization. Furthermore, this review also provides a comprehensive summary of the efficacious treatment strategies aimed at enhancing diabetic wound healing through the regulation of macrophage polarization. By encompassing a thorough understanding of the fundamental principles and their practical implementation, the advancement of treatment strategies for diabetic wounds can be further facilitated.

Double-Layer Hydrogel with Glucose-Activated Two-Stage ROS Regulating Properties for Programmed Diabetic Wound Healing

Slow healing of wounds induces great pain in diabetic patients. However, developing new approaches to promote diabetic wound healing is still one of the toughest challenges in the medical field. Here, we constructed a new double-layer hydrogel to effectively regulate reactive oxygen species (ROS) on the wound and promote diabetic wound healing. The inner layer contains glucose oxidase (Gox), ferrocene-modified quaternary ammonium chitosan (Fc-QCs), and poly(β-cyclodextrin) (Pβ-CD), which is used to generate hydroxyl radicals (•OH) for antibacterial in the early stage of wound healing and collapses gradually. The outer layer is composed of gelatin and dopamine. In the later stage of wound healing, the outer layer contacts the skin, which is beneficial for ROS clearance on the wound. Antibacterial, ROS scavenging, and wound healing experiments have shown that the double-layer hydrogel possesses two-stage ROS regulating properties for programmed diabetic wound healing. In conclusion, it will be one of the most potential dressings for treating diabetic wounds in the future.

Optimization and Characterization of a Novel Antioxidant Naringenin-Loaded Hydrogel for Encouraging Re-Epithelization in Chronic Diabetic Wounds: A Preclinical Study

Nonhealed wounds are one of the most dangerous side effects of type-2 diabetes, which is linked to a high frequency of bacterial infections around the globe that eventually results in amputation of limbs. The present investigation aimed to explore the drug-loaded (naringenin) hydrogel system for chronic wound healing. The hydrogel membranes comprising Na-alginate with F-127 and poly(vinyl alcohol) were developed to treat chronic wounds using the quality-by-design (QbD) approach. The optimized formulation was tested for various parameters, such as swelling, gel fraction, water vapor transition rate (WVTR), etc. In vitro evaluation indicated that a drug-loaded hydrogel displayed better tissue adhesiveness and can release drugs for a prolonged duration of 12 h. Scratch assay performed on L929 cell lines demonstrated good cell migration. The diabetic wound healing potential of the hydrogel membrane was assessed in streptozotocin-induced male Wistar rats (50 mg/kg). Higher rates of wound closure, re-epithelialization, and accumulation of collagen were seen in in vivo experiments. Histopathologic investigation correspondingly implied that the drug-loaded hydrogel could enhance dermal wound repair. The improved antimicrobial and antioxidant properties with expedited healing indicated that the drug-loaded hydrogel is a perfect dressing for chronic wounds.

Sustained Releasable Copper and Zinc Biogenic Ions Co-Assembled in Metal-Organic Frameworks Reinforced Bacterial Eradication and Wound Mitigation in Diabetic Mice

The employment of metal-organic framework (MOF)-based nanomaterials has been rapidly increasing in bioapplications owing to their biocompatibility, drug degradation, tunable porosity, and intrinsic biodegradability. This evidence suggests that the multifunctional bimetallic ions can behave as remarkable candidates for infection control and wound healing. In this study, bimetallic MOFs (Zn-HKUST-1 and FolA-Zn-HKUST-1) embedded with and without folic acid were synthesized and used for tissue sealing and repairing incisional wound sites in mice models. For comparison, HKUST-1 and FolA-HKUST-1 were also synthesized. The Brunauer-Emmett-Teller (BET) surface area measured for HKUST-1, FolA-HKUST-1, Zn-HKUST-1, and FolA-Zn-HKUST-1 from N2 isotherms was found to be 1868, 1392, 1706, and 1179 m2/g, respectively. The measurements of contact angle values for Zn-HKUST-1, FolA-HKUST-1, and Zn-FolA-HKUST-1 were identified as 4.95 ± 0.8, 43.6 ± 3.4, and 60.62 ± 2.0°, respectively. For topical application in wound healing, they display a wide range of healing characteristics, including antibacterial and enhanced wound healing rates. In addition, in vitro cell migration and tubulogenic potentials were evaluated. The significant reduction in the wound gap and increased expression levels for CD31, eNOS, VEGF-A, and Ki67 were observed from immunohistological analyses to predict the angiogenesis behavior at the incision wound site. The wound healing rate was analyzed in the excisional dermal wounds of diabetic mice model in vivo. On account of antibacterial potentials and tissue-repairing characteristics of Cu2+ and Zn2+ ions, designing an innovative mixed metal ion-based biomaterial has wide applicability and is expected to modulate the growth of various gradient tissues.

Electrospun polyvinyl alcohol/Withania somnifera extract nanofibers incorporating tadalafil-loaded nanoparticles for diabetic ulcers

Background: Impaired inflammation and vascularization are common reasons for delayed diabetic wound healing. Nanoparticles (NPs)-in-nanofibers composites can manage diabetic wounds. A multifunctional scaffold was developed based on tadalafil (TDF)-loaded NPs incorporated into polyvinyl alcohol/Withania somnifera extract nanofibers. Materials & methods: TDF-loaded NPs were prepared and fully characterized in terms of their physicochemical properties. Extract of ashwagandha was prepared and a blend composed of TDF-loaded NPs, herbal extract and polyvinyl alcohol was used to prepare the whole composite. Results: The whole composite exhibited improved wound closure in a diabetic rat model in terms of reduced inflammation and enhanced angiogenesis. Conclusion: Results suggest that this multifunctional composite could serve as a promising diabetic wound dressing.

Advancements and Insights in Exosome-Based Therapies for Wound Healing: A Comprehensive Systematic Review (2018-June 2023)

Exosomes have shown promising potential as a therapeutic approach for wound healing. Nevertheless, the translation from experimental studies to commercially available treatments is still lacking. To assess the current state of research in this field, a systematic review was performed involving studies conducted and published over the past five years. A PubMed search was performed for English-language, full-text available papers published from 2018 to June 2023, focusing on exosomes derived from mammalian sources and their application in wound healing, particularly those involving in vivo assays. Out of 531 results, 148 papers were selected for analysis. The findings revealed that exosome-based treatments improve wound healing by increasing angiogenesis, reepithelization, collagen deposition, and decreasing scar formation. Furthermore, there was significant variability in terms of cell sources and types, biomaterials, and administration routes under investigation, indicating the need for further research in this field. Additionally, a comparative examination encompassing diverse cellular origins, types, administration pathways, or biomaterials is imperative. Furthermore, the predominance of rodent-based animal models raises concerns, as there have been limited advancements towards more complex in vivo models and scale-up assays. These constraints underscore the substantial efforts that remain necessary before attaining commercially viable and extensively applicable therapeutic approaches using exosomes.