Double-network hydrogel enhanced by SS31-loaded mesoporous polydopamine nanoparticles: Symphonic collaboration of near-infrared photothermal antibacterial effect and mitochondrial maintenance for full-thickness wound healing in diabetes mellitus

HAMA-SBMA hydrogel with anti-inflammatory properties delivers cartilage organoids, boosting cartilage regeneration

Cartilage tissue lacks blood supply, which limits its ability to self-repair. Cartilage organoid (CO) technology, which replicates the structure and function of cartilage, holds significant promise. However, it is essential to maintain cellular function and ensure secure fixation at the site of injury. Therefore, we loaded allogeneic bone marrow mesenchymal stem cells (BMSCs) onto decellularized extracellular matrix microparticles of porcine articular cartilage (CEP) to construct CO-CCO, which demonstrated characteristics of articular cartilage. Additionally, betaine sulfonate methacrylate (SBMA) was incorporated into hyaluronic acid methacrylate (HAMA) to synthesize a novel hydrogel, HAMA-SBMA (HS), characterized by its adhesive properties, promotion of chondrogenesis, and inhibition of inflammation. In Vivo studies revealed that the combination of HS and CCO (HS + CCO) exhibited excellent repair efficacy in both rat and sheep models of cartilage defects. Mechanistically, we found that HS + CCO promoted cartilage repair by activating the Frizzled-related protein (Frzb), which inhibited inflammatory factors and enhanced the expression of the adhesion factor integrin ɑ5β1. This strategy, which combines hydrogels and organoids, enhances cartilage repair, offering substantial potential for clinical applications in cartilage regeneration.

Injectable nanocomposite hydrogel for localized precision delivery of dexamethasone after traumatic brain injury: dual modulation of neuroinflammation and blood-brain barrier restoration

BACKGROUND

Glucocorticoids (GCs) have been widely used in the treatment of severe traumatic brain injury (TBI) to inhibit neuroinflammation and alleviating brain edema and cannot be replaced by other drugs. However, their systemic application still faces many obstacles, such as the poor blood-brain-barrier (BBB) penetration and severe side effects. Therefore, new treatment strategy or compounds are urgently needed in clinic.

METHODS

Herein, an injectable nanocomposite hydrogel is developed as a biofunctionalized delivery platform for intraoperative administration of dexamethasone (DEX) after TBI. By using a mice TBI model, the safety and efficacy of the nanohydrogels in treating BBB disruption, brain edema and nerve injury were evaluated after TBI.

RESULTS

The hydrogel is composed of polysaccharide matrix (carboxymethyl chitosan and oxidized dextran) and mesoporous polydopamine (MPDA) nanoparticles loaded with DEX (MPDA@DEX@gel) that could realize in situ injection, self-assembly, a high DEX loading rate and sustained release around the lesion. The MPDA@DEX@gel exhibits excellent antibacterial and hemostatic properties, good biocompatibility and antioxidation, and self-healing capability in vitro. These in vitro and in vivo results show that local application of MPDA@DEX@gel not only alleviates brain edema, promotes neuronal survival, and improves neurological function by restoring the integrity of BBB and inhibiting neuroinflammation after TBI, but also effectively avoids the peripheral and central side effects.

CONCLUSION

Our study provides a promising treatment strategy for the rational use of GCs in patients with severe TBI.

Polymeric Nanomedicines in Diabetic Wound Healing: Applications and Future Perspectives

The management of diabetic wound continues to pose significant clinical obstacles, primarily attributed to bacterial infections, excessive inflammation, oxidative stress, and impaired angiogenesis. These pathological factors not only severely affect patient well-being but also create considerable burden on medical services. Current managements often show limited efficacy, necessitating the exploration of alternative therapeutic strategies. Polymeric nanomedicines (PNs), owing to their nanoscale properties, enhanced cellular uptake, stability, bioavailability, and biocompatibility, have been broadly utilized for diabetic wound treatment. PNs demonstrate remarkable capabilities in microbial inhibition, inflammation regulation, oxidative stress mitigation, and vascular network formation, particularly when combined with various agents, including organic substances (eg, exosomes), inorganic substances (eg, metals), and biomaterials (eg, chitosan, hyaluronic acid, and hydrogels). This article systematically examines recent progress in PN-based interventions for diabetic wound recovery, highlighting the pivotal role of PNs in mitigating bacterial infection, modulating inflammatory responses, and promoting cellular regeneration. Additionally, we provide a novel perspective on the multifunctionality of PNs and their potential for overcoming the limitations of conventional therapies. Overall, PNs represent an innovative and promising approach to diabetic wound management, outperforming conventional therapies in stability, targeted delivery, and multifunctionality. In the future, investigations should concentrate on refining PNs formulations and administration strategies so as to enhance biocompatibility, and conducting well-designed clinical trials to validate their therapeutic efficacy.

Multifunctional dynamic chitosan-guar gum nanocomposite hydrogels in infection and diabetic wound healing

Traditional wound care methods are less effective for infectious and diabetic wounds, highlighting an urgent need for effective strategies. The study aimed to design a self-healing hydrogel with antibacterial, antioxidant, and photothermal capabilities to treat infectious and diabetic wounds. Silver nanoparticles (AgNPs) were loaded into mesoporous polydopamine (MPDA) nanoparticles to form Ag@MPDA nanoparticles. Ag@MPDA was incorporated into the cationic guar gum-chitosan-boric acid (CCB) hydrogel to obtain the PA-CCB hydrogel. PA-CCB hydrogel exhibited excellent self-healing and adhesive properties, adapting well to the dynamic wound environment. PA-CCB hydrogel combined with photothermal therapy (PTT) could effectively eradicated E. coli (99.9 %) and S. aureus (99.7 %). The PA-CCB hydrogel reduced excessive reactive oxygen species and promoted the migration of fibroblasts in vitro. In the infected mouse wound models, the PA-CCB hydrogel effectively inhibited bacteria. After combining with PTT, the antibacterial ability of the PA-CCB hydrogel was further enhanced. In the diabetic mouse wound models, the PA-CCB hydrogel reduced the inflammatory level of wound tissue. In both models, after combining with PTT, the PA-CCB hydrogel exhibited further improvements in angiogenesis, collagen deposition, and re-epithelialization. By integrating multifunctional hydrogel with PTT, the PA-CCB hydrogel exhibited broad application potential for infectious and diabetic wounds.

Gold@Mesoporous Polydopamine Nanocomposite Hydrogel Loaded with Estrogen for the Treatment of Skin Photoaging

Introduction

Topical application of 17β-estradiol (E2) has been shown to improve various hallmark features of skin aging, including enhancing skin elasticity and hydration, reducing wrinkles, and promoting collagen synthesis. However, the role of estrogen in UVB-induced photoaging of the skin remains unclear. Furthermore, E2's clinical application is limited by issues such as bioavailability and potential adverse effects. Therefore, this study aims to explore the role of E2 in UVB-induced skin photoaging and to prepare a gold (Au)@mesoporous polydopamine (mPDA)-hyaluronic acid (HA)/carboxymethyl chitosan (CMCS) nanoparticle composite hydrogel (Au/E2@mPDA-HCG) for the treatment of skin photoaging.

Methods

This study successfully fabricated mPDA with a well-defined mesoporous structure and incorporated Au NPs into the mesopores of mPDA using an in situ growth method, thereby constructing Au@mPDA NPs loaded with E2. Subsequently, the Au/E2@mPDA NPs were embedded into a HA/CMCS hydrogel to develop the Au/E2@mPDA-HCG nanoparticle composite hydrogel. The composite hydrogel was characterized through in vitro and in vivo experiments, and its efficacy in improving skin photoaging was evaluated.

Results

This study revealed that estrogen deficiency significantly exacerbates UVB-induced skin photoaging, likely through mechanisms closely associated with increased oxidative stress and reduced collagen production. Moreover, the Au/E2@mPDA-HCG nanoparticle composite hydrogel demonstrated favorable morphological characteristics and biocompatibility. In vitro and in vivo experimental results indicated that this composite hydrogel effectively enhanced the therapeutic efficacy of E2 in treating skin photoaging, as evidenced by its significant mitigation of oxidative stress and inflammatory responses, along with the promotion of collagen synthesis.

Conclusion

In conclusion, this study suggests that the combination of E2 with Au@mPDA@HCG nanocomposite hydrogel offers a promising therapeutic strategy for UVB-induced skin photoaging.

Bioinspired conductive oriented nanofiber felt with efficient ROS clearance and anti-inflammation for inducing M2 macrophage polarization and accelerating spinal cord injury repair

Complete spinal cord injury (SCI) causes permanent locomotor, sensory and neurological dysfunctions. Targeting complex immunopathological microenvironment at SCI sites comprising inflammatory cytokines infiltration, oxidative stress and massive neuronal apoptosis, the conductive oriented nanofiber felt with efficient ROS clearance, anti-inflammatory effect and accelerating neural regeneration is constructed by step-growth addition polymerization and electrostatic spinning technique for SCI repair. The formation of innovative Fe3+-PDA-PAT chelate in nanofiber felt enhances hydrophilic, antioxidant, antibacterial, hemostatic and binding factor capacities, thereby regulating immune microenvironment of SCI. With the capabilities of up-regulating COX5A and STAT6 expressions, down-regulating the expressions of IL1β, CD36, p-ERK, NFκB2 and NFκB signaling pathway proteins, the nanofiber felt attenuates oxidative stress injury, promotes M2 macrophage polarization and down-regulates inflammatory response. After implantation into complete transection SCI rats, the nanofiber felt is revealed to recruit endogenous NSCs, induce the differentiation of NSCs into neurons while inhibit astrocytes formation and inflammation, reduces glia scar, and promotes angiogenesis, remyelination and neurological functional recovery. Overall, this innovative strategy provides a facile immune regulatory system to inhibit inflammatory response and accelerate nerve regeneration after SCI, and its targeted proteins and mechanisms are first elucidated, which holds great application promise in clinical treatment of complete SCI.

Recent advances in hyaluronic acid-based hydrogels for diabetic wound healing

Diabetic wound healing represents a complex biological challenge, often impeded by disrupted cellular processes and dysregulated inflammation, which can lead to chronic and non-healing wounds. Given the significant burden on patients and the healthcare system, there is an urgent need for advanced therapeutic strategies. Hyaluronic acid (HA)-based hydrogels have emerged as a promising solution due to their biocompatibility, biodegradability, and unique physiological functions. This review aims to provide a comprehensive overview of recent advances in HA-based hydrogels, highlighting their potential in addressing diabetic wound complications. Specifically, it examines challenges such as hyperglycemia-induced oxidative stress and impaired cellular signaling within the intricate diabetic wound microenvironment. Moreover, the review explores the composition and properties of HA, including its adhesive capabilities and role in reducing surgical trauma. Various crosslinking strategies and functional modifications are also discussed to endow HA-based hydrogels with antioxidant, antimicrobial, and growth factor-releasing capabilities. By summarizing the latest research and identifying areas for further exploration, this review contributes to the development of more effective HA-based hydrogel formulations for diabetic wound healing.

The Extracellular Matrix Promotes Diabetic Oral Wound Healing by Modulating the Microenvironment

Oral wounds in diabetes mellitus (DM) often delay healing due to reduced angiogenesis and increased inflammatory response in the local microenvironment, even leading to graft necrosis and implant failure. Therefore, developing an effective program to promote healing is of great clinical value. Much of the current research is focused on promoting wound healing through surface adhesive materials that exert a pro-angiogenic, anti-inflammatory effect. However, the application of surface bonding materials in the oral cavity is very limited due to the humid and friction-prone environment. Decellularized extracellular adipose tissue (DAT) is an easily accessible and biocompatible material derived from adipose tissue. To further explore the potential of DAT, we used multi-omics to analyze its composition and possible mechanisms. Proteomic studies revealed that DAT contains anti-inflammatory, pro-angiogenic proteins that promote DM tissue regeneration. To adapt to the moist and chewing friction environment of the mouth, we modified DAT into a temperature-sensitive hydrogel material that can be injected intramucosally. DAT hydrogel has been verified to promote angiogenesis and exert anti-inflammatory effects through macrophage phenotypic transformation. Meanwhile, transcriptome analysis suggested that the inhibitory effect of DAT on the interleukin 17 signaling pathway might be a key factor in promoting DM oral wound healing. In conclusion, after multi-omic analysis, DAT hydrogel can exert good pro-angiogenic and anti-inflammatory effects through the interleukin 17 signaling pathway and can be adapted to the specific environment of the oral cavity. This provides a potential way to promote DM oral wound healing in a clinical setting.

Recent advances and challenges in metal-based antimicrobial materials: a review of strategies to combat antibiotic resistance

Despite the availability of a series of classical antibiotic drugs, bacterial infections continue to represent a significant and urgent threat to global human health. The emergence of drug-resistant bacteria and the slow pace of antibiotic development have rendered current treatment methods inadequate in meeting the clinical demands of bacterial infections. Consequently, there is an increasingly urgent and vital need for the development of safe, efficient, and alternative novel antimicrobial agents in the medical and healthcare field. Over the past five years, there has been a notable expansion in the field of nanomedicine with regard to the prevention and control of infectious diseases. The objective of this article is to provide a comprehensive review of the latest research developments in the field of metal nanomaterials for medical antimicrobial therapy. We begin by delineating the gravity of the bacterial infection crisis, subsequently undertaking a comprehensive examination of the potential mechanisms through which nanoparticles may combat bacterial infections and the specific applications of these nanomaterials in the treatment of diverse infectious diseases. In conclusion, we eagerly anticipate the future development directions of metal nanomaterials in the field of antimicrobial therapy. We believe that with continuous technological advancements and innovations, this field will make even more outstanding contributions to safeguarding human health and well-being.

Bioactive Zn-V-Si-Ca Glass Nanoparticle Hydrogel Microneedles with Antimicrobial and Antioxidant Properties for Bone Regeneration in Diabetic Periodontitis

Periodontitis is a chronic inflammatory condition affecting the periodontal tissue. This condition worsens in diabetic patients due to oxidative stress and inflammation. Herein, we investigated a treatment using bioactive Zn-V-Si-Ca glass nanoparticle hydrogel microneedles. The microneedles contain bioactive glass nanoparticles codoped with zinc and vanadium ions. They also include gallic acid and oxidized methacrylated hyaluronic acid. These microneedles address bacterial dysbiosis and oxidative stress in diabetic periodontitis. They provide antibacterial and antioxidant effects. The microneedles deliver therapeutic agents directly into the gingival tissue. This enhances drug retention and absorption by penetrating the mucosal barrier. In vitro studies demonstrated biocompatibility, excellent antioxidant properties, and acceptable mechanical properties. Meanwhile, the microneedle patches demonstrated antibacterial properties effective against a Gram-negative periodontal pathogen as well as a Gram-positive oral bacterium. In vivo experiments were performed using a diabetic rat model with periodontitis. Results showed significant improvement in alveolar bone regeneration. The hydrogel modulated the inflammatory microenvironment effectively. Ribonucleic acid sequencing revealed downregulation of JAK-STAT and NF-κB inflammation signaling pathways. This work presents a distinctive approach to suppressing the inflammatory response and modulate immune responses for the purpose of treating diabetic periodontitis early.

Yeast-Inspired Orally-Administered Nanocomposite Scavenges Oxidative Stress and Restores Gut Immune Homeostasis for Inflammatory Bowel Disease Treatment

Excessive oxidative stress, dysregulated immune homeostasis, and disruption of the intestinal epithelial barrier are crucial features of inflammatory bowel disease (IBD). Traditional treatments focusing solely on inflammation resolution remain unsatisfactory. Herein, a yeast-inspired orally administered nanocomposite was developed. First, the MD@MPDA core was fabricated by integrating manganese dioxide (MnO2) nanozymes onto diallyl trisulfide (H2S prodrug)-loaded mesoporous polydopamine nanoparticles (MPDA). Then, yeast cell wall (YCW) was chosen to encapsulate MD@MPDA, namely, YMD@MPDA. The β-glucan embedded in the YCW shell not only protected the nanocomposite from the harsh gastrointestinal environment but also allowed the targeting enrichment in the inflamed colon. Furthermore, M1 macrophages triggered the intracellular GSH-responsive H2S release in the pathological microenvironment. MD@MPDA effectively alleviated inflammatory responses by MnO2-mediated ROS-scavenging and H2S-participated immunomodulation. The synergistic action contributed to macrophage mitochondrial function restoration and M2 polarization by suppressing NOX4 signaling and p38 MAPK pro-inflammatory signaling. In the mice model of dextran sulfate sodium (DSS)-induced IBD, the multipronged manner of scavenging oxidative stress, remodeling innate and adaptive immune homeostasis, and reshaping gut microbiota caused by YMD@MPDA effectively ameliorated inflammation and restored intestinal barrier functions. Overall, the YMD@MPDA nanocomposite provides a promising codelivery strategy of antioxidative nanozymes and gas prodrugs for the comprehensive management of IBD.

Targeted and Synergistic Codelivery of Chemotherapeutic and Nucleic Acid Drugs by Liposome-Coated MPDA Nanoparticles for Advanced Prostate Cancer Treatment

Docetaxel (DTX)-based chemotherapy is the primary therapeutic approach for advanced prostate cancer (PCa) when endocrine therapy proves ineffective. Traditional chemotherapy exhibits poor specificity and induces severe side effects, such as immunosuppression, neurotoxicity, and hypersensitivity. In this study, we aimed to develop a new targeted nanodrug delivery system to accurately identify PCa cells and deliver drugs. We prepared mesoporous polydopamine (MPDA) nanoparticles using a one-pot method. After loading DTX onto MPDA, siRNA was attached to the surface, which was coated with polyethylene glycol lipids film (PEG-Lips); together, this formed MDS@L. The aptamer A10-3.2 was coupled to the surface of PEG-Lips to obtain MDS@LA, which was characterized using different techniques, including transmission electron microscopy and Fourier transform infrared spectroscopy. MDS@LA exhibited excellent stability, acid-responsive release, and photothermal properties, enhancing its antitumor effects. Both in vitro and in vivo experiments revealed that MDS@LA precisely targeted PCa cells and effectively delivered DTX and siRNA, leading to significant inhibition of PCa cell growth and proliferation. This versatile nanoplatform offers a promising, precise, and efficient therapeutic approach for advanced PCa, addressing the limitations of conventional chemotherapy.

Self-Cascade of ROS/Glucose-Scavenging Immunomodulatory Hydrogels for Programmed Therapeutics of Infected Diabetic Ulcers via Nrf2/NF-κB Pathway

Diabetic ulcers (DUs) are characterized by a microenvironment with high oxidative stress, high blood glucose levels, and recalcitrant bacterial infections. This microenvironment is accompanied by long-term suppression of endogenous antioxidant systems, which makes their clinical management extremely challenging. To address this issue, a hybridized novel gold-palladium (AuPd) nanoshell of the injectable/injectable hydrogel system UiO/AuPdshells/BNN6/PEG@Gel (UAPsBP@Gel) is developed. The system is capable of acting as a nitric oxide (NO) reactor utilizing synergistic therapy that harnesses NIR-II light-triggered photothermal effects and controlled release of NO gas for synergistic treatment to eradicate biofilm infections at different depths. The AuPd nanoshells exhibits superoxide dismutase (SOD)-, glucose oxidase (GOx)-, and catalase (CAT)-like activities, enabling self-cascade process for scavenging both reactive oxygen species (ROS) and glucose. This activity reshapes the DUs microenvironment, switches on the endogenous antioxidant Nrf2/HO-1 pathway and inhibits the NF-κB pathway, promotes macrophage polarization toward the anti-inflammatory M2 phenotype, and reduces oxidative stress, resulting in efficient immunomodulation. In vitro/in vivo results demonstrate that the UAPsBP@Gel can multifacetedly enhance the epithelial rejuvenation process through wound hemostasis, pro-cellular migration and vascularization. These results highlight that a programmed therapeutic based on UBAPsP@Gel tailored to the different stages of infected DUs can meet complex clinical needs.

Glucose oxidase: An emerging multidimensional treatment option for diabetic wound healing

The healing of diabetic skin wounds is a complex process significantly affected by the hyperglycemic environment. In this context, glucose oxidase (GOx), by catalyzing glucose to produce gluconic acid and hydrogen peroxide, not only modulates the hyperglycemic microenvironment but also possesses antibacterial and oxygen-supplying functions, thereby demonstrating immense potential in the treatment of diabetic wounds. Despite the growing interest in GOx-based therapeutic strategies in recent years, a systematic summary and review of these efforts have been lacking. To address this gap, this review article outlines the advancements in the application of GOx and GOx-like nanozymes in the treatment of diabetic wounds, including reaction mechanisms, the selection of carrier materials, and synergistic therapeutic strategies such as multi-enzyme combinations, microneedle structures, and gas therapy. Finally, the article looks forward to the application prospects of GOx in aiding the healing of diabetic wounds and the challenges faced in translating these innovations to clinical practice. We sincerely hope that this review can provide readers with a comprehensive understanding of GOx-based diabetic treatment strategies, facilitate the rigorous construction of more robust multifunctional therapeutic systems, and ultimately benefit patients with diabetic wounds.

Microenvironment Remodeling Microgel Repairs Degenerated Intervertebral Disc via Programmed Delivery of MicroRNA-155

The progression of intervertebral disc degeneration (IVDD) is associated with increased cell apoptosis and reduced extracellular matrix (ECM) production, both of which are driven by ongoing inflammation. Thus, alleviating the acidic inflammatory microenvironment and mitigating the apoptosis of nucleus pulposus cells (NPCs) are essential for intervertebral disc (IVD) regeneration. Regulating pH levels in the local environment can reduce inflammation and promote tissue recovery. In this study, a lactic acid-capturing microgel carrying a functionalized miRNA-155 nanocarrier was designed for IVD regeneration. microRNA-155 was loaded into the NPC-targeted nanogel via host-guest binding. The miR-155 nanocarrier (NGM) achieved lactic acid-sensitive release of miRNA-155, resulting in rapid regulation of apoptosis. Moreover, SS31, which dissociated from the nanogel network, had the ability to regulate mitochondrial metabolism. Moreover, the microgel was constructed using a matrix metalloproteinase-responsive peptide. The chitosan coating on the microgel system was ingeniously employed to capture lactic acid and enable pH-responsive dissociation, thereby alleviating the acidic microenvironment to protect cell viability and facilitate the delivery of the NGM. The microgel system effectively promoted IVD regeneration by alleviating the acidic microenvironment and preventing NPC apoptosis.

Collagen-Based Nanoparticles as Drug Delivery System in Wound Healing Applications

Background

Conventional wound dressings often adhere to wounds and can cause secondary injury due to their lack of anti-inflammatory and antibacterial properties. In contrast, collagen-based nanoparticles (NPs) as drug delivery systems exhibit both biocompatibility and biodegradability, presenting a promising avenue for accelerating wound healing processes.

Aims of Study

This review aims to provide a comprehensive overview of the mechanisms involved in wound healing, description of the attributes of ideal wound dressings, understanding of wound healing efficacy of collagen, exploring NPs-mediated drug delivery mechanisms in wound therapy, detailing the synthesis and fabrication techniques of collagen-based NPs, and delineating the applications of various collagen-based NPs infused wound dressings on wound healing.

Methodology

This review synthesizes relevant literature from reputable databases such as Scopus, Science Direct, Google Scholar, and PubMed.

Results

A diverse array of collagen-based NPs, including nanopolymers, metal NPs, nanoemulsions, nanoliposomes, and nanofibers, demonstrate pronounced efficacy in promoting wound closure and tissue regeneration. The incorporation of collagen-based NPs has not only become an agent for the delivery of therapeutics but also actively contributes to the wound healing cascade.

Conclusion

In conclusion, In brief, the use of collagen-based NPs presents a compelling strategy for expediting wound healing processes.

On-demand Opto-Laser activatable nanoSilver ThermoGel for treatment of full-thickness diabetic wound in a mouse model

Patients suffering from diabetes mellitus are prone to develop diabetic wounds that are non-treatable with conventional therapies. Hence, there is an urgent need of hour to develop the therapy that will overcome the lacunas of conventional therapies. This investigation reports the Quality by Design-guided one-pot green synthesis of unique Opto-Laser activatable nanoSilver ThermoGel (OL→nSil-ThermoGel) for hyperthermia-assisted treatment of full-thickness diabetic wounds in mice models. The characterization findings confirmed the formation of spherical-shaped nanometric Opto-Laser activatable nanoSilver (30.75 ± 2.7 nm; ∆T: 37 ± 0.2 °C → 66.2 ± 0.1 °C; at 1.8 W/cm2 NIR laser density). The findings indicated acceptable in vitro cytocompatibility and significant keratinocyte migration (95.04 ± 0.07 %) activity of OL→nSil towards HaCaT cells. The rheological data of OL→nSil hybridized in situ thermoresponsive gel (OL→nSil-ThermoGel) showed the gelling temperature at 32 ± 2 °C. In vivo studies on full-thickness diabetic wounds in a Mouse model showed OL→nSil-ThermoGel accelerated wound closure (94.42 ± 1.03 %) and increased collagen synthesis, angiogenesis, and decreased inflammatory markers. Similarly, immunohistochemistry study showed significant angiogenesis and faster phenotypic switching of fibroblasts to myofibroblasts in OL→nSil-ThermoGel treated diabetic wounds. Histological evaluation revealed a marked rise in keratinocyte migration, organized collagen deposition, and early regeneration of the epithelial layer compared to the diabetic wound control. In conclusion, the OL→nSil-ThermoGel modulates the cytokines, re-epithelialization, protein expression, and growth factors, thereby improving the repair and regeneration of diabetic wounds in mice.

Plant-inspired visible-light-driven bioenergetic hydrogels for chronic wound healing

Chronic bioenergetic imbalances and inflammation caused by hyperglycemia are obstacles that delay diabetic wound healing. However, it is difficult to directly deliver energy and metabolites to regulate intracellular energy metabolism using biomaterials. Herein, we propose a light-driven bioenergetic and oxygen-releasing hydrogel (PTKM@HG) that integrates the thylakoid membrane-encapsulated polyphenol nanoparticles (PTKM NPs) to regulate the energy metabolism and inflammatory response in diabetic wounds. Upon red light irradiation, the PTKM NPs exhibited oxygen generation and H2O2 deletion capacity through a photosynthetic effect to restore hypoxia-induced mitochondrial dysfunction. Meanwhile, the PTKM NPs could produce exogenous ATP and NADPH to enhance mitochondrial function and facilitate cellular anabolism by regulating the leucine-activated mTOR signaling pathway. Furthermore, the PTKM NPs inherited antioxidative and anti-inflammatory ability from polyphenol. Finally, the red light irradiated PTKM@HG hydrogel augmented the survival and migration of cells keratinocytes, and then accelerated angiogenesis and re-epithelialization of diabetic wounds. In short, this study provides possibilities for effectively treating diseases by delivering key metabolites and energy based on such a light-driven bioenergetic hydrogel.

Nanotechnology-Mediated Immunomodulation Strategy for Inflammation Resolution

Inflammation serves as a common characteristic across a wide range of diseases and plays a vital role in maintaining homeostasis. Inflammation can lead to tissue damage and the onset of inflammatory diseases. Although significant progress is made in anti-inflammation in recent years, the current clinical approaches mainly rely on the systemic administration of corticosteroids and antibiotics, which only provide short-term relief. Recently, immunomodulatory approaches have emerged as promising strategies for facilitating the resolution of inflammation. Especially, the advanced nanosystems with unique biocompatibility and multifunctionality have provided an ideal platform for immunomodulation. In this review, the pathophysiology of inflammation and current therapeutic strategies are summarized. It is mainly focused on the nanomedicines that modulate the inflammatory signaling pathways, inflammatory cells, oxidative stress, and inflammation targeting. Finally, the challenges and opportunities of nanomaterials in addressing inflammation are also discussed. The nanotechnology-mediated immunomodulation will open a new treatment strategy for inflammation therapy.

Hydrogen Sulfide Delivery System Based on Salting-Out Effect for Enhancing Synergistic Photothermal and Photodynamic Cancer Therapies

The simultaneous application of photothermal therapy (PTT) and photodynamic therapy (PDT) offers substantial advantages in cancer treatment. However, their synergistic anticancer efficacy is often limited by tumor hypoxia, and thermotolerance induced by high expression of heat shock proteins (HSP). Fortunately, hydrogen sulfide (H2S), known for its direct cytotoxic effect on tumor cells, has been recognized for its ability to enhance PTT and PDT. The effectiveness of H2S in these therapies is challenged by its low loading efficiency, poor stability, and short diffusion distance. To address these issues, a nanoscale emulsion drop template created through the salting-out effect is employed to construct a robust H2S delivery system. Polydopamine (PDA), chosen for its interfacial polymerization tendency and excellent photothermal conversion rate, is utilized as a carrier for the H2S donor (ADT) and Zinc phthalocyanine (ZnPc) to fabricate a novel nanomedicine termed APZ NPs. The temperature-responsive APZ NPs are designed to release H2S during the PTT process. Elevated H2S levels promoted vasodilation, thereby enhancing the enhanced permeability and retention effect (EPR) of APZ NPs within solid tumors. This strategy effectively alleviated tumor hypoxia by disrupting the mitochondrial respiratory chain and mitigated tumor cell heat tolerance by inhibiting HSP expression.

Precise subcellular targeting approaches for organelle-related disorders

Pharmacological research has expanded to the nanoscale level with advanced imaging technologies, enabling the analysis of drug distribution at the cellular organelle level. These advances in research techniques have contributed to the targeting of cellular organelles to address the fundamental causes of diseases. Beyond navigating the hurdles of reaching lesion tissues upon administration and identifying target cells within these tissues, controlling drug accumulation at the organelle level is the most refined method of disease management. This approach opens new avenues for the development of more potent therapeutic strategies by delving into the intricate roles and interplay of cellular organelles. Thus, organelle-targeted approaches help overcome the limitations of conventional therapies by precisely regulating functionally compartmentalized spaces based on their environment. This review discusses the basic concepts of organelle targeting research and proposes strategies to target diseases arising from organelle dysfunction. We also address the current challenges faced by organelle targeting and explore future research directions.

Customized Vascular Repair Microenvironment: Poly(lactic acid)-Gelatin Nanofibrous Scaffold Decorated with bFGF and Ag@Fe3O4 Core-Shell Nanowires

Vascular defects caused by trauma or vascular diseases can significantly impact normal blood circulation, resulting in serious health complications. Vascular grafts have evolved as a popular approach for vascular reconstruction with promising outcomes. However, four of the greatest challenges for successful application of small-diameter vascular grafts are (1) postoperative anti-infection, (2) preventing thrombosis formation, (3) utilizing the inflammatory response to the graft to induce tissue regeneration and repair, and (4) noninvasive monitoring of the scaffold and integration. The present study demonstrated a basic fibroblast growth factor (bFGF) and oleic acid dispersed Ag@Fe3O4 core-shell nanowires (OA-Ag@Fe3O4 CSNWs) codecorated poly(lactic acid) (PLA)/gelatin (Gel) multifunctional electrospun vascular grafts (bAPG). The Ag@Fe3O4 CSNWs have sustained Ag+ release and exceptional photothermal capabilities to effectively suppress bacterial infections both in vitro and in vivo, noninvasive magnetic resonance imaging (MRI) modality to monitor the position of the graft, and antiplatelet adhesion properties to promise long-term patency. The gradually released bFGF from the bAPG scaffold promotes the M2 macrophage polarization and enhances the recruitment of macrophages, endothelial cells (ECs) and fibroblast cells. This significant regulation of diverse cell behavior has been proven to be beneficial to vascular repair and regeneration both in vitro and in vivo. Therefore, this study supplies a method to prepare multifunctional vascular-repair materials and is expected to represent a significant guidance and reference to the development of biomaterials for vascular tissue engineering.

Decellularized Tumor Tissues Integrated with Polydopamine for Wound Healing

Natural biomaterials have been showing extensive potential in wound healing; attempts therefore focus on productions achieving both antimicrobial and tissue regenerative abilities. Here, we construct a decellularized human colon tumor (DHCT)-derived scaffold for wound remolding via microfluidic bioprinting. The DHCT retains a series of growth factors, fibrin, and the collagen configuration, that favor tissue repair and reconstruction. Specifically, the scaffold shows superior abilities in cell migration and angiogenesis. The biocompatible scaffold is also imparted with tissue adhesion ability and photothermal effect due to the coating of biologically derived polydopamine on the surface. The strong photothermal effect under near-infrared irradiation also present the scaffold with an antibacterial rate exceeding 90%. Furthermore, in vivo experiments convinced that the polydopamine-integrated DHCT scaffold can markedly expedite the healing process of acute extensive wounds. These findings indicate that composite materials derived from natural tumors have substantial potential in pertinent clinical applications.

Stimuli-Mediated Macrophage Switching, Unraveling the Dynamics at the Nanoplatforms-Macrophage Interface

Macrophages play an essential role in immunotherapy and tissue regeneration owing to their remarkable plasticity and diverse functions. Recent bioengineering developments have focused on using external physical stimuli such as electric and magnetic fields, temperature, and compressive stress, among others, on micro/nanostructures to induce macrophage polarization, thereby increasing their therapeutic potential. However, it is difficult to find a concise review of the interaction between physical stimuli, advanced micro/nanostructures, and macrophage polarization. This review examines the present research on physical stimuli-induced macrophage polarization on micro/nanoplatforms, emphasizing the synergistic role of fabricated structure and stimulation for advanced immunotherapy and tissue regeneration. A concise overview of the research advancements investigating the impact of physical stimuli, including electric fields, magnetic fields, compressive forces, fluid shear stress, photothermal stimuli, and multiple stimulations on the polarization of macrophages within complex engineered structures, is provided. The prospective implications of these strategies in regenerative medicine and immunotherapeutic approaches are highlighted. This review will aid in creating stimuli-responsive platforms for immunomodulation and tissue regeneration.

Healing the diabetic wound: Unlocking the secrets of genes and pathways

Diabetic wounds (DWs) are open sores that can occur anywhere on a diabetic patient's body. They are often complicated by infections, hypoxia, oxidative stress, hyperglycemia, and reduced growth factors and nucleic acids. The healing process involves four phases: homeostasis, inflammation, proliferation, and remodeling, regulated by various cellular and molecular events. Numerous genes and signaling pathways such as VEGF, TGF-β, NF-κB, PPAR-γ, MMPs, IGF, FGF, PDGF, EGF, NOX, TLR, JAK-STAT, PI3K-Akt, MAPK, ERK, JNK, p38, Wnt/β-catenin, Hedgehog, Notch, Hippo, FAK, Integrin, and Src pathways are involved in these events. These pathways and genes are often dysregulated in DWs leading to impaired healing. The present review sheds light on the pathogenesis, healing process, signaling pathways, and genes involved in DW. Further, various therapeutic strategies that target these pathways and genes via nanotechnology are also discussed. Additionally, clinical trials on DW related to gene therapy are also covered in the present review.

A bioenergetically-active ploy (glycerol sebacate)-based multiblock hydrogel improved diabetic wound healing through revitalizing mitochondrial metabolism

Diabetic wounds impose significant burdens on patients' quality of life and healthcare resources due to impaired healing potential. Factors like hyperglycemia, oxidative stress, impaired angiogenesis and excessive inflammation contribute to the delayed healing trajectory. Mounting evidence indicates a close association between impaired mitochondrial function and diabetic complications, including chronic wounds. Mitochondria are critical for providing energy essential to wound healing processes. However, mitochondrial dysfunction exacerbates other pathological factors, creating detrimental cycles that hinder healing. This study conducted correlation analysis using clinical specimens, revealing a positive correlation between mitochondrial dysfunction and oxidative stress, inflammatory response and impaired angiogenesis in diabetic wounds. Restoring mitochondrial function becomes imperative for developing targeted therapies. Herein, we synthesized a biodegradable poly (glycerol sebacate)-based multiblock hydrogel, named poly (glycerol sebacate)-co-poly (ethylene glycol)-co-poly (propylene glycol) (PEPGS), which can be degraded in vivo to release glycerol, a crucial component in cellular metabolism, including mitochondrial respiration. We demonstrate the potential of PEPGS-based hydrogels to improve outcomes in diabetic wound healing by revitalizing mitochondrial metabolism. Furthermore, we investigate the underlying mechanism through proteomics analysis, unravelling the regulation of ATP and nicotinamide adenine dinucleotide metabolic processes, biosynthetic process and generation during mitochondrial metabolism. These findings highlight the therapeutic potential of PEPGS-based hydrogels as advanced wound dressings for diabetic wound healing.

Endogenous Melanin and Hydrogen-Based Specific Activated Theranostics Nanoagents: A Novel Multi-Treatment Paradigm for Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disorder characterized by excessive proliferation of rheumatoid arthritis synovial fibroblasts (RASFs) and accumulation of inflammatory cytokines. Exploring the suppression of RASFs and modulation of the RA microenvironment is considered a comprehensive strategy for RA. In this work, specifically activated nanoagents (MAHI NGs) based on the hypoxic and weakly acidic RA microenvironment are developed to achieve a second near-infrared fluorescence (NIR-II FL)/photoacoustic (PA) dual-model imaging-guided multi-treatment. Due to optimal size, the MAHI NGs passively accumulate in the diseased joint region and undergo rapid responsive degradation, precisely releasing functionalized components: endogenous melanin-nanoparticles (MNPs), hydrogen gas (H2), and indocyanine green (ICG). The released MNPs play a crucial role in ablating RASFs within the RA microenvironment through photothermal therapy (PTT) guided by accurate PA imaging. However, the regional hyperthermia generated by PTT may exacerbate reactive oxygen species (ROS) production and inflammatory response following cell lysis. Remarkably, under the acidic microenvironment, the controlled release of H2 exhibits precise synergistic antioxidant and anti-inflammatory effects with MNPs. Moreover, the ICG, the second near-infrared dye currently approved for clinical use, possesses excellent NIR-II FL imaging properties that facilitate the diagnosis of deep tissue diseases and provide the right time-point for PTT.

Application research of novel peptide mitochondrial-targeted antioxidant SS-31 in mitigating mitochondrial dysfunction

Due to the pivotal role of mitochondria in the generation of adenosine triphosphate (ATP) and the regulation of cellular homeostasis, mitochondrial dysfunction may exert a profound impact on various physiological systems, potentially precipitating a spectrum of distinct diseases. Consequently, research pertaining to mitochondrial therapeutics has assumed increasing significance, warranting heightened scrutiny. In recent years, the field of mitochondrial therapy has witnessed noteworthy advancements, with active exploration into diverse pharmacological agents aimed at ameliorating mitochondrial function. Elamipretide (SS-31), a novel synthetic mitochondrial-targeted antioxidant, has emerged as a promising candidate with extensive therapeutic potential. Its notable attributes encompass the mitigation of oxidative stress, the suppression of inflammatory processes, the maintenance of mitochondrial dynamics, and the prevention of cellular apoptosis. As such, SS-31 may emerge as a viable choice for the treatment of mitochondrial dysfunction-related ailments in the foreseeable future. This article extensively expounds upon the superiority of SS-31 over natural antioxidants and traditional mitochondrial-targeted antioxidants, delves into its mechanisms of modulating mitochondrial function, and comprehensively summarizes its applications in alleviating mitochondrial dysfunction-associated disorders. Furthermore, we offer a comprehensive outlook on the expansive prospects of SS-31's future development and application.

Multifunctional biomimetic hydrogel dressing provides anti-infection treatment and improves immunotherapy by reprogramming the infection-related wound microenvironment

The advancement of biomaterials with antimicrobial and wound healing properties continues to present challenges. Macrophages are recognized for their significant role in the repair of infection-related wounds. However, the interaction between biomaterials and macrophages remains complex and requires further investigation. In this research, we propose a new sequential immunomodulation method to enhance and expedite wound healing by leveraging the immune properties of bacteria-related wounds, utilizing a novel mixed hydrogel dressing. The hydrogel matrix is derived from porcine acellular dermal matrix (PADM) and is loaded with a new type of bioactive glass nanoparticles (MBG) doped with magnesium (Mg-MBG) and loaded with Curcumin (Cur). This hybrid hydrogel demonstrates controlled release of Cur, effectively eradicating bacterial infection in the early stage of wound infection, and the subsequent release of Mg ions (Mg2+) synergistically inhibits the activation of inflammation-related pathways (such as MAPK pathway, NF-κB pathway, TNF-α pathway, etc.), suppressing the inflammatory response caused by infection. Therefore, this innovative hydrogel can safely and effectively expedite wound healing during infection. Our design strategy explores novel immunomodulatory biomaterials, offering a fresh approach to tackle current clinical challenges associated with wound infection treatment.

Pluronic F127-Lipoic Acid Adhesive Nanohydrogel Combining with Ce3+/Tannic Acid/Ulinastatin Nanoparticles for Promoting Wound Healing

Developing strong anti-inflammatory wound dressings is of great significance for protecting inflammatory cutaneous wounds and promoting wound healing. The present study develops a nanocomposite Pluronic F127 (F127)-based hydrogel dressing with injectable, tissue adhesive, and anti-inflammatory performance. Briefly, Ce3+/tannic acid/ulinastatin nanoparticles (Ce3+/TA/UTI NPs) are fabricated. Meanwhile, α-lipoic acid is bonded to the ends of F127 to prepare F127-lipoic acid (F127LA) and its nanomicelles. Due to the gradual viscosity change instead of mutation during phase transition, the mixed Ce3+/TA/UTI NPs and F127LA nanomicelles show well-performed injectability at 37 °C and can form a semisolid composite nanohydrogel that can tightly attach to the skin at 37 °C. Furthermore, ultraviolet (UV) irradiation without a photoinitiator transforms the semisolid hydrogel into a solid hydrogel with well-performed elasticity and toughness. The UV-cured composite nanohydrogel acts as a bioadhesive that can firmly adhere to tissues. Due to the limited swelling property, the hydrogel can firmly adhere to tissues in a wet environment, which can seal wounds and provide a reliable physical barrier for the wounds. Ce3+/TA/UTI NPs in the hydrogel exhibit lipopolysaccharide (LPS)-scavenging ability and reactive oxygen species (ROS)-scavenging ability and significantly reduce the expression of inflammatory factors in wounds at the early stage, accelerating LPS-induced wound healing.

Progress in Pluronic F127 Derivatives for Application in Wound Healing and Repair

Pluronic F127 hydrogel biomaterial has garnered considerable attention in wound healing and repair due to its remarkable properties including temperature sensitivity, injectability, biodegradability, and maintain a moist wound environment. This comprehensive review provides an in-depth exploration of the recent advancements in Pluronic F127-derived hydrogels, such as F127-CHO, F127-NH2, and F127-DA, focusing on their applications in the treatment of various types of wounds, ranging from burns and acute wounds to infected wounds, diabetic wounds, cutaneous tumor wounds, and uterine scars. Furthermore, the review meticulously examines the intricate interaction mechanisms employed by these hydrogels within the wound microenvironment. By elucidating the underlying mechanisms, discussing the strengths and weaknesses of Pluronic F127, analyzing the current state of wound healing development, and expanding on the trend of targeting mitochondria and cells with F127 as a nanomaterial. The review enhances our understanding of the therapeutic effects of these hydrogels aims to foster the development of effective and safe wound-healing modalities. The valuable insights provided this review have the potential to inspire novel ideas for clinical treatment and facilitate the advancement of innovative wound management approaches.