Microneedle/CD-MOF-mediated transdural controlled release of methylprednisolone sodium succinate after spinal cord injury

Injectable thermosensitive hydrogel system based on hyaluronic acid and methylcellulose for the synergistic therapy of traumatic spinal cord injury

Spinal cord injury (SCI) is a neurological disease with a high rate of disability. Inflammation plays a key role in all stages of pathological of SCI and interacts with ferroptosis to induce deterioration. Methylprednisolone sodium succinate (MPSS) is currently the only drug in clinical to treat SCI through anti-inflammation, but due to the lack of efficacy and systemic adverse reactions, the drug therapy of SCI is still limited. Therefore, a locally administered injectable thermosensitive hydrogel MPSS/Fer-1@HA-MC was designed to treat SCI synergistically by anti-inflammation and anti-ferroptosis. Considering the insolubility of Fer-1 in water, Fer-1@β-CD inclusion complex was used to co-contained with MPSS in HA-MC hydrogel. Faster release of dissolved MPSS inhibits inflammation in acute and subacute stages of SCI. With a smaller solubility of Fer-1@β-CD, Fer-1 released slowly and persistently to anti-ferroptosis and anti-inflammation in whole stages. Therefore, motricity function of SCI mouse was repaired after treat with MPSS/Fer-1@HA-MC, better than single-drug hydrogels. Furthermore, MPSS/Fer-1@HA-MC inhibit inflammatory damage by decreased the expression of IL-1β, CD68, ROS and iNOS, and inhibit ferroptosis by reduced the overexpression of TfR1 and lipid peroxidation, and increased GPX4 level in whole stages. In summary, MPSS/Fer-1@HA-MC successfully achieved a more sustained and comprehensive therapeutic of SCI.

Microneedle-Enabled Breakthroughs in Nucleic Acid Therapeutics

Nucleic acid therapy demonstrates great potential in cancer treatment, infectious disease prevention, and vaccine development due to its advantages, such as rapid production, long-lasting effects, and high target specificity. Although nucleic acid therapy is considered ideal for the development of novel therapeutic strategies, its clinical application still faces numerous challenges, including the lack of efficient delivery systems, insufficient drug formulation stability, and the limitations imposed by the skin barrier on drug dosage delivery. Microneedles, as an innovative transdermal drug delivery technology, can penetrate the stratum corneum and directly access the skin's microcirculation, enabling the efficient delivery of genes and drugs. This technology offers several advantages, such as ease of operation, minimally invasive and painless application, and high safety. Combining microneedle technology with nucleic acid therapy fully leverages the strengths of both approaches, significantly enhancing therapeutic efficacy and bioavailability while maximizing treatment potential. This review explores the application prospects and advantages of combining microneedle delivery systems with nucleic acid therapy.

Microneedle-aided nanotherapeutics delivery and nanosensor intervention in advanced tissue regeneration

Microneedles (MNs) have been extensively used as transdermal therapeutics delivery devices since 1998 due to their capacity to penetrate physiological barriers with minimal invasiveness. Recent advances demonstrate the potential of MNs in improving diverse tissue regeneration when integrated with nanometer-sized therapeutics or sensors. This synergistic strategy can enhance drug delivery efficiency and therapeutic outcomes, and enable precise and personalized therapies through real-time monitoring of the repair process. In this review, we discuss how optimized MNs (through adjustments in geometry, material properties, and modular structure), when combined with dimension- and composition-specific nanomaterials, enhance tissue regeneration efficiency. Moreover, integrating stimuli-responsive nanotherapeutics or nanosensors into MNs for spatiotemporal-controlled and targeted drug release, physiotherapy effects, and intelligent monitoring is systematically outlined. Furthermore, we summarize therapeutic applications of nanotherapeutics-MN platforms in various soft and hard tissues, including skin, hair follicles (HF), cornea, joint, tendons, sciatic nerves, spinal cord, periodontium, oral mucosa, myocardium, endometrium, bone and intervertebral discs (IVD). Notably, recent attempts using nanosensor-MN platforms as smart wearable devices for monitoring damaged tissues via interstitial fluid (ISF) extraction and biomarker sensing are analyzed. This review potentially provides tissue regeneration practitioners/researchers with a cross-disciplinary perspective and inspiration.

Microneedle-based nanodrugs for tumor immunotherapy

Microneedles have emerged as a promising and effective method for delivering therapeutic drugs and immunobiologics to treat various diseases. It is widely recognized that immune therapy has limited efficacy in solid tumors due to physical barriers and the immunosuppressive tumor microenvironment. Microneedle-based nanodrugs (NDMNs) offer a novel approach to overcome these limitations. These tiny needles are designed to load a variety of inorganic and organic nanoparticles, antigen vaccines, gene drugs, oncolytic viruses, and more. Utilizing microneedle arrays, NDMNs can effectively penetrate the skin barrier, delivering drugs precisely to the tumor site or immunoactive regions within the skin. Additionally, by designing and optimizing the microneedle structure, shape, and functionality, NDMNs enable precise drug release and efficient penetration, thereby enhancing the efficacy of tumor immunotherapy. In this review, we comprehensively discuss the pivotal role of NDMNs in cancer immunotherapy, summarizing innovative microneedle design strategies, mechanisms of immune activation, and delivery strategies of various nanodrugs. Furthermore, we explore the current clinical realities, limitations, and future prospects of NDMNs in tumor immunotherapy.

Applications of Cyclodextrin-Based Drug Delivery Systems in Inflammation-Related Diseases

Currently, inflammation diseases are one of the leading causes of mortality worldwide. The therapeutic drugs for inflammation are mainly steroidal and non-steroidal anti-inflammatory drugs. However, the use of these anti-inflammatory drugs over a prolonged period is prone to causing serious side effects. Accordingly, it is particularly critical to design an intelligent target-specific drug delivery system to control the release of drugs in order to mitigate the side effects of anti-inflammatory drugs without limiting their activity. Meanwhile, cyclodextrin-based nano-delivery systems have garnered significant attention in contemporary pharmaceutical research owing to their capacity to enhance drug bioavailability, enable site-specific targeted accumulation, prolong the systemic circulation duration, facilitate synergistic therapeutic outcomes, and exhibit superior biocompatibility profiles. It is worth noting that cyclodextrin-based drug delivery systems show great potential in inflammation-related diseases. However, few studies have systematically reviewed their design strategies and application advancements. Here, we summarize the structural and chemical modification strategies of cyclodextrins, as well as cyclodextrin-based drug delivery systems and their applications in inflammation-related diseases. In summary, the aim is to provide a bit of insight into the development of cyclodextrin-based drug delivery systems for inflammation-related diseases.

Metal-organic framework microneedles for precision transdermal drug delivery: design strategy and therapeutic potential

Metal-organic frameworks (MOFs) are porous materials renowned for their high porosity, large specific surface area, biocompatibility, and biodegradability. Hydrogel microneedles (MNs) is an emerging technology that minimally disrupts the skin or mucosal membranes, bypassing gastrointestinal absorption and the rapid metabolism typical of oral drug delivery. Over the past few decades, both MOFs and MNs have found applications across a range of fields. However, MOFs alone cannot penetrate the skin or mucosal barrier to deliver drugs effectively, and MNs have limited direct loading capacity. When combined, MOFs enhance the loading efficiency of therapeutic agents in hydrogel MNs and optimize their release kinetics. Additionally, the incorporation of MOFs improves the mechanical properties of hydrogel MNs, increasing their permeability to the skin. In turn, hydrogel MNs enable MOFs-whether therapeutically active or drug-loaded-to bypass the skin or mucosal barrier and deliver active compounds directly to the target site for localized treatment. This review discusses the structural features and preparation methods of MOFs and MOF-based MNs, explores their synergistic potential, and highlights strategies for integrating MOFs with MNs to enhance transdermal drug delivery in applications such as wound healing, scar management, acne treatment, and tumor suppression. Finally, we examine the challenges and future potential of MOF-based MNs and offer insights into their role in advancing transdermal therapies.

Methylprednisolone substituted lipid nanoparticles deliver C3 transferase mRNA for combined treatment of spinal cord injury

Spinal cord injury (SCI), characterized by the disruption of neural pathways and an increase in inflammatory cell infiltration, leads to profound and lasting neurological deficits, with a high risk of resulting in permanent disability. Currently, the therapeutic landscape for SCI is notably sparse, with limited effective treatment options available. Methylprednisolone (MP), a widely used clinical anti-inflammatory agent for SCI, requires administration in high doses that are associated with significant adverse effects. In this study, we introduce an innovative approach by substituting cholesterol with MP to engineer a novel Lipid Nanoparticle (MP-LNP). This strategy aims to enhance the localization and concentration of MP at the injury site, thereby amplifying its therapeutic efficacy while mitigating systemic side effects. Furthermore, we explore the integration of C3 transferase mRNA into MP-LNPs. C3 transferase, a potent inhibitor of the RhoA pathway, has shown promise in facilitating neurological recovery in animal models of SCI and is currently being evaluated in clinical trials. The novel formulation, MP-LNP-C3, is designed for direct administration to the injury site during decompression surgery, offering a targeted therapeutic modality for SCI. Our findings reveal several significant advantages of this approach: Firstly, the incorporation of C3 transferase mRNA into MP-LNPs does not compromise the structural integrity of the nanoparticles, ensuring efficient mRNA expression within the spinal cord. Secondly, the MP-LNP formulation effectively attenuates inflammation and reduces the adverse effects associated with high-dose MP treatment in the acute phase of SCI. Lastly, MP-LNP-C3 demonstrates notable neuroprotective properties and promotes enhanced recovery of motor function in SCI mouse models. Together, these results underscore the potential of this innovative LNP-based therapy as a promising avenue for advancing the treatment of clinical SCI.

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.

Targeted microbiota dysbiosis repair: An important approach to health management after spinal cord injury

Current research primarily focuses on the pathological mechanisms of spinal cord injury (SCI), seeking to promote spinal cord repair and restore motorial and sensory functions by elucidating mechanisms of cell death or axonal regeneration. However, SCI is almost irreversible, and patients often struggle to regain mobility or self-care abilities after injuries. Consequently, there has been significant interest in modulating systemic symptoms following SCI to improve patients' quality of life. Neuron axonal disconnection and substantial apoptotic events following SCI result in signal transmission loss, profoundly impacting various organ and systems, including the gastrointestinal tract. Dysbiosis can lead to severe bowel dysfunction in patients, substantially lowering their quality of life and significantly reducing life expectancy of them. Therefore, researches focusing on the restoration of the gut microbiota hold promise for potential therapeutic strategies aimed at rehabilitation after SCI. In this paper, we explore the regulatory roles that dietary fiber, short-chain fatty acids (SCFAs), probiotics, and microbiota transplantation play in patients with SCI, summarize the potential mechanisms of post-SCI dysbiosis, and discuss possible strategies to enhance long-term survival of SCI patients. We aim to provide potential insights for future research aimed at ameliorating dysbiosis in SCI patients.

Regulation of dynamic spatiotemporal inflammation by nanomaterials in spinal cord injury

Spinal cord injury (SCI) is a common clinical condition of the central nervous system that can lead to sensory and motor impairment below the injury level or permanent loss of function in severe cases. Dynamic spatiotemporal neuroinflammation is vital to neurological recovery, which is collectively constituted by the dynamic changes in a series of inflammatory cells, including microglia, neutrophils, and astrocytes, among others. Immunomodulatory nanomaterials can readily improve the therapeutic effects and simultaneously overcome various drawbacks associated with treatment, such as the off-target side effects and loss of bioactivity of immune agents during circulation. In this review, we discuss the role of dynamic spatiotemporal inflammation in secondary injuries after SCI, elaborate on the mechanism of action and effect of existing nanomaterials in treating SCI, and summarize the mechanism(s) whereby they regulate inflammation. Finally, the challenges and prospects associated with using nanotechnology to modulate immunotherapy are discussed to provide new insights for future treatment. Deciphering the intricate spatiotemporal mechanisms of neuroinflammation in SCI requires further in-depth studies. Therefore, SCI continues to represent a formidable challenge.

An integrated long-acting implant of clinical safe cells, drug and biomaterials effectively promotes spinal cord repair and restores motor functions

Spinal cord injury (SCI) is incurable and raises growing concerns. The main barrier to nerve repair is the complicated inhibitory microenvironment, where single-targeted strategies are largely frustrated. Despite the progress in combinatory therapeutic systems, the development and translation of effective therapies remain a challenge with extremely limited clinical materials. In this study, mesenchymal stem cells are transplanted in combination with sustained release of methylprednisolone through delivery in one composite matrix of a microsphere-enveloped adhesive hydrogel. All the materials used, including the stem cells, drug, and the matrix polymers gelatin and hyaluronan, are clinically approved. The therapeutic effects and safety issues are evaluated on rat and canine SCI models. The implantation significantly promotes functional restoration and nerve repair in a severe long-span rat spinal cord transection model. Distant spinal cord segments and the urinary system are effectively protected against pathologic damage. Moreover, the local sustained drug delivery mitigates the inflammatory microenvironment when overcoming the clinical issue of systemic side effects. The study presents an innovative strategy to achieve safe and efficient combinatory treatment of SCI.

Natural Polyphenol Delivered Methylprednisolone Achieve Targeted Enrichment for Acute Spinal Cord Injury Therapy

The strong anti-inflammatory effect of methylprednisolone (MP) is a necessary treatment for various severe cases including acute spinal cord injury (SCI). However, concerns have been raised regarding adverse effects from MP, which also severely limits its clinical application. Natural polyphenols, due to their rich phenolic hydroxyl chemical properties, can form dynamic structures without additional modification, achieving targeted enrichment and drug release at the disease lesion, making them a highly promising carrier. Considering the clinical application challenges of MP, a natural polyphenolic platform is employed for targeted and efficient delivery of MP, reducing its systemic side effects. Both in vitro and SCI models demonstrated polyphenols have multiple advantages as carriers for delivering MP: (1) Achieved maximum enrichment at the injured site in 2 h post-administration, which met the desires of early treatment for diseases; (2) Traceless release of MP; (3) Reducing its side effects; (4) Endowed treatment system with new antioxidative properties, which is also an aspect that needs to be addressed for diseases treatment. This study highlighted a promising prospect of the robust delivery system based on natural polyphenols can successfully overcome the barrier of MP treatment, providing the possibility for its widespread clinical application.

Hydrogel-based therapeutic strategies for spinal cord injury repair: Recent advances and future prospects

Spinal cord injury (SCI) is a debilitating condition that can result in significant functional impairment and loss of quality of life. There is a growing interest in developing new therapies for SCI, and hydrogel-based multimodal therapeutic strategies have emerged as a promising approach. They offer several advantages for SCI repair, including biocompatibility, tunable mechanical properties, low immunogenicity, and the ability to deliver therapeutic agents. This article provides an overview of the recent advances in hydrogel-based therapy strategies for SCI repair, particularly within the past three years. We summarize the SCI hydrogels with varied characteristics such as phase-change hydrogels, self-healing hydrogel, oriented fibers hydrogel, and self-assembled microspheres hydrogel, as well as different functional hydrogels such as conductive hydrogels, stimuli-responsive hydrogels, adhesive hydrogel, antioxidant hydrogel, sustained-release hydrogel, etc. The composition, preparation, and therapeutic effect of these hydrogels are briefly discussed and comprehensively evaluated. In the end, the future development of hydrogels in SCI repair is prospected to inspire more researchers to invest in this promising field.

Synergistic applications of cyclodextrin-based systems and metal-organic frameworks in transdermal drug delivery for skin cancer therapy

This review article explores the innovative field of eco-friendly cyclodextrin-based coordination polymers and metal-organic frameworks (MOFs) for transdermal drug delivery in the case of skin cancer therapy. We critically examine the significant advancements in developing these nanocarriers, with a focus on their unique properties such as biocompatibility, targeted drug release, and enhanced skin permeability. These attributes are instrumental in addressing the limitations inherent in traditional skin cancer treatments and represent a paradigm shift towards more effective and patient-friendly therapeutic approaches. Furthermore, we discuss the challenges faced in optimizing the synthesis process for large-scale production while ensuring environmental sustainability. The review also emphasizes the immense potential for clinical applications of these nanocarriers in skin cancer therapy, highlighting their role in facilitating targeted, controlled drug release which minimizes systemic side effects. Future clinical applications could see these nanocarriers being customized to individual patient profiles, potentially revolutionizing personalized medicine in oncology. With further research and clinical trials, these nanocarriers hold the promise of transforming the landscape of skin cancer treatment. With this study, we aim to provide a comprehensive overview of the current state of research in this field and outline future directions for advancing the development and clinical application of these innovative nanocarriers.

Potential Application Prospects of Biomolecule-Modified Two-Dimensional Chiral Nanomaterials in Biomedicine

Chirality, one of the most fundamental properties of natural molecules, plays a significant role in biochemical reactions. Nanomaterials with chiral characteristics have superior properties, such as catalytic properties, optoelectronic properties, and photothermal properties, which have significant potential for specific applications in nanomedicine. Biomolecular modifications such as nucleic acids, peptides, proteins, and polysaccharides are sources of chirality for nanomaterials with great potential for application in addition to intrinsic chirality, artificial macromolecules, and metals. Two-dimensional (2D) nanomaterials, as opposed to other dimensions, due to proper surface area, extensive modification sites, drug loading potential, and simplicity of preparation, are prepared and utilized in diagnostic applications, drug delivery research, and tumor therapy. Current advanced studies on 2D chiral nanomaterials for biomedicine are focused on novel chiral development, structural control, and materials sustainability applications. However, despite the advances in biomedical research, chiral 2D nanomaterials still confront challenges such as the difficulty of synthesis, quality control, batch preparation, chiral stability, and chiral recognition and selectivity. This review aims to provide a comprehensive overview of the origins, synthesis, applications, and challenges of 2D chiral nanomaterials with biomolecules as cargo and chiral modifications and highlight their potential roles in biomedicine.

Application of metal-organic frameworks-based functional composite scaffolds in tissue engineering

With the rapid development of materials science and tissue engineering, a variety of biomaterials have been used to construct tissue engineering scaffolds. Due to the performance limitations of single materials, functional composite biomaterials have attracted great attention as tools to improve the effectiveness of biological scaffolds for tissue repair. In recent years, metal-organic frameworks (MOFs) have shown great promise for application in tissue engineering because of their high specific surface area, high porosity, high biocompatibility, appropriate environmental sensitivities and other advantages. This review introduces methods for the construction of MOFs-based functional composite scaffolds and describes the specific functions and mechanisms of MOFs in repairing damaged tissue. The latest MOFs-based functional composites and their applications in different tissues are discussed. Finally, the challenges and future prospects of using MOFs-based composites in tissue engineering are summarized. The aim of this review is to show the great potential of MOFs-based functional composite materials in the field of tissue engineering and to stimulate further innovation in this promising area.

Metal-organic framework-based platforms for implantation applications: recent advances and challenges

The development of minimally invasive technology has promoted the widespread use of implant interventional materials, which play an important role in alleviating patients' pain during and after surgery. Metal-organic frameworks (MOFs) and their related hybrids formed by bridging ligands and metal nodes via covalent bonds represent one of the smart platforms in implant interventional fields due to their large surface area, adjustable compositions and structures, biodegradability, etc. Significant progresses in the implantation application of MOF-based materials have been achieved recently, but these studies are still in the initial stage. This review highlights the recent advances of MOFs and their related hybrids in orthopedic implantation, cardio-vascular implantation, neural tissue engineering, and biochemical sensing. Each correction between the structural features of MOFs and their corresponding implanted works is highlighted. Finally, the confronting challenges and future perspectives in the implant interventional field are discussed.

M2 microglia-derived exosome-loaded electroconductive hydrogel for enhancing neurological recovery after spinal cord injury

Electroconductive hydrogels offer a promising avenue for enhancing the repair efficacy of spinal cord injuries (SCI) by restoring disrupted electrical signals along the spinal cord's conduction pathway. Nonetheless, the application of hydrogels composed of diverse electroconductive materials has demonstrated limited capacity to mitigate the post-SCI inflammatory response. Recent research has indicated that the transplantation of M2 microglia effectively fosters SCI recovery by attenuating the excessive inflammatory response. Exosomes (Exos), small vesicles discharged by cells carrying similar biological functions to their originating cells, present a compelling alternative to cellular transplantation. This investigation endeavors to exploit M2 microglia-derived exosomes (M2-Exos) successfully isolated and reversibly bonded to electroconductive hydrogels through hydrogen bonding for synergistic promotion of SCI repair to synergistically enhance SCI repair. In vitro experiments substantiated the significant capacity of M2-Exos-laden electroconductive hydrogels to stimulate the growth of neural stem cells and axons in the dorsal root ganglion and modulate microglial M2 polarization. Furthermore, M2-Exos demonstrated a remarkable ability to mitigate the initial inflammatory reaction within the injury site. When combined with the electroconductive hydrogel, M2-Exos worked synergistically to expedite neuronal and axonal regeneration, substantially enhancing the functional recovery of rats afflicted with SCI. These findings underscore the potential of M2-Exos as a valuable reparative factor, amplifying the efficacy of electroconductive hydrogels in their capacity to foster SCI rehabilitation.