Efficient delivery of VEGF-A mRNA for promoting diabetic wound healing via ionizable lipid nanoparticles

Basic immunologic study as a foundation for engineered therapeutic development

Bioengineering and drug delivery technologies play an important role in bridging the gap between basic scientific discovery and clinical application of therapeutics. To identify the optimal treatment, the most critical stage is to diagnose the problem. Often these two may occur simultaneously or in parallel, but in this review, we focus on bottom-up approaches in understanding basic immunologic phenomena to develop targeted therapeutics. This can be observed in several fields; here, we will focus on one of the original immunotherapy targets-cancer-and one of the more recent targets-regenerative medicine. By understanding how our immune system responds in processes such as malignancies, wound healing, and medical device implantation, we can isolate therapeutic targets for pharmacologic and bioengineered interventions.

Transdermal gene delivery

Gene delivery has revolutionized conventional medical approaches to vaccination, cancer, and autoimmune diseases. However, current gene delivery methods are limited to either intravenous administration or direct local injections, failing to achieve well biosafety, tissue targeting, drug retention, and transfection efficiency for desired therapeutic outcomes. Transdermal drug delivery based on various delivery strategies can offer improved therapeutic potential and superior patient experiences. Recently, there has been increased foundational and clinical research focusing on the role of the transdermal route in gene delivery and exploring its impact on the efficiency of gene delivery. This review introduces the recent advances in transdermal gene delivery approaches facilitated by drug formulations and medical devices, as well as discusses their prospects.

Promoting the healing of diabetic wounds with an antimicrobial gel containing AgNPs with anti-infective and anti-inflammatory properties

Diabetic wounds are prone to develop chronic wounds due to bacterial infection and persistent inflammatory response. However, traditional dressings are monofunctional, lack bioactive substances, have limited bacterial inhibition as well as difficulties in adhesion and retention. These limit the therapeutic efficacy of traditional dressings on diabetic wounds. Therefore, finding and developing efficient and safe wound dressings is currently an urgent clinical need. In this study, an antimicrobial gel loaded with silver nanoparticles (AgNPs) (referred to as AgNPs@QAC-CBM) was prepared by crosslinking quaternary ammonium chitosan (QAC) with carbomer (CBM) as a gel matrix. AgNPs@QAC-CBM exhibited a reticulated structure, strong adhesion, good stability, and remarkable bactericidal properties, killing 99.9% of Escherichia coli, Staphylococcus aureus, Candida albicans, and Pseudomonas aeruginosa within 1 min. Furthermore, AgNPs@QAC-CBM improved the wound microenvironment and accelerated wound healing in diabetic mice by promoting tissue production and collagen deposition, inducing M2 macrophages, reducing pro-inflammatory factor secretion and increasing anti-inflammatory factor levels. Moreover, AgNPs@QAC-CBM was proven to be safe for use through skin irritation and cytotoxicity tests, as they did not cause any irritation or toxicity. To summarize, AgNPs@QAC-CBM showed promising potential in enhancing the diabetic wound healing process.

Accelerating diabetic wound healing by ROS-scavenging lipid nanoparticle-mRNA formulation

Current treatment options for diabetic wounds face challenges due to low efficacy, as well as potential side effects and the necessity for repetitive treatments. To address these issues, we report a formulation utilizing trisulfide-derived lipid nanoparticle (TS LNP)-mRNA therapy to accelerate diabetic wound healing by repairing and reprogramming the microenvironment of the wounds. A library of reactive oxygen species (ROS)-responsive TS LNPs was designed and developed to encapsulate interleukin-4 (IL4) mRNA. TS2-IL4 LNP-mRNA effectively scavenges excess ROS at the wound site and induces the expression of IL4 in macrophages, promoting the polarization from the proinflammatory M1 to the anti-inflammatory M2 phenotype at the wound site. In a diabetic wound model of db/db mice, treatment with this formulation significantly accelerates wound healing by enhancing the formation of an intact epidermis, angiogenesis, and myofibroblasts. Overall, this TS LNP-mRNA platform not only provides a safe, effective, and convenient therapeutic strategy for diabetic wound healing but also holds great potential for clinical translation in both acute and chronic wound care.

Growth factors and growth factor gene therapies for treating chronic wounds

Chronic wounds are an unmet clinical need affecting millions of patients globally, and current standards of care fail to consistently promote complete wound closure and prevent recurrence. Disruptions in growth factor signaling, a hallmark of chronic wounds, have led researchers to pursue growth factor therapies as potential supplements to standards of care. Initial studies delivering growth factors in protein form showed promise, with a few formulations reaching clinical trials and one obtaining clinical approval. However, protein-form growth factors are limited by instability and off-target effects. Gene therapy offers an alternative approach to deliver growth factors to the chronic wound environment, but safety concerns surrounding gene therapy as well as efficacy challenges in the gene delivery process have prevented clinical translation. Current growth factor delivery and gene therapy approaches have primarily used single growth factor formulations, but recent efforts have aimed to develop multi-growth factor approaches that are better suited to address growth factor insufficiencies in the chronic wound environment, and these strategies have demonstrated improved efficacy in preclinical studies. This review provides an overview of chronic wound healing, emphasizing the need and potential for growth factor therapies. It includes a summary of current standards of care, recent advances in growth factor, cell-based, and gene therapy approaches, and future perspectives for multi-growth factor therapeutics.

Narrative review on nanoparticles based on current evidence: therapeutic agents for diabetic foot infection

Diabetes's effects on wound healing present a major treatment challenge and increase the risk of amputation. When traditional therapies fail, new approaches must be investigated. With their submicron size and improved cellular internalisation, nanoparticles present a viable way to improve diabetic wound healing. They are attractive options because of their innate antibacterial qualities, biocompatibility, and biodegradability. Nanoparticles loaded with organic or inorganic compounds, or embedded in biomimetic matrices such as hydrogels, chitosan, and hyaluronic acid, exhibit excellent anti-inflammatory, antibacterial, and antioxidant properties. Drug delivery systems (DDSs)-more precisely, nanodrug delivery systems (NDDSs)-use the advantages of nanotechnology to get around some of the drawbacks of traditional DDSs. Recent developments show how expertly designed nanocarriers can carry a variety of chemicals, transforming the treatment of diabetic wounds. Biomaterials that deliver customised medications to the wound microenvironment demonstrate potential. Delivery techniques for nanomedicines become more potent than ever, overcoming conventional constraints. Therapeutics for diabetes-induced non-healing wounds are entering a revolutionary era thanks to precisely calibrated nanocarriers that effectively distribute chemicals. This review highlights the therapeutic potential of nanoparticles and outlines the multifunctional nanoparticles of the future that will be used for complete wound healing in diabetics. The investigation of novel nanodrug delivery systems has the potential to revolutionise diabetic wound therapy and provide hope for more efficient and focused therapeutic approaches.

Topical gene editing therapeutics using lipid nanoparticles: 'gene creams' for genetic skin diseases?

Patients living with inherited skin diseases have benefited from recent advances in DNA sequencing technologies that provide new or improved diagnostics. However, developing and delivering new treatments for the 'genodermatoses' remains challenging. The goal of creating topical preparations that can recover the inherent gene pathology remains largely aspirational. However, recent progress in two fields - the chemistry of topical delivery formulations (lipid nanoparticles) and the molecular biology of gene repair (CRISPR-Cas9, base and prime editing) - presents new opportunities to address this unmet need. In this review, we discuss how lipid nanoparticle delivery vehicles could be used to deliver gene-editing tools to formulate topical 'gene creams' suitable for the treatment of genodermatoses. We summarize the historical landscape of topical therapeutics and advances in gene editing that may herald an era of new therapies for patients with inherited skin disorders.

Engineered mRNA Delivery Systems for Biomedical Applications

Messenger RNA (mRNA)-based therapeutic strategies have shown remarkable promise in preventing and treating a staggering range of diseases. Optimizing the structure and delivery system of engineered mRNA has greatly improved its stability, immunogenicity, and protein expression levels, which has led to a wider range of uses for mRNA therapeutics. Herein, a thorough analysis of the optimization strategies used in the structure of mRNA is first provided and delivery systems are described in great detail. Furthermore, the latest advancements in biomedical engineering for mRNA technology, including its applications in combatting infectious diseases, treating cancer, providing protein replacement therapy, conducting gene editing, and more, are summarized. Lastly, a perspective on forthcoming challenges and prospects concerning the advancement of mRNA therapeutics is offered. Despite these challenges, mRNA-based therapeutics remain promising, with the potential to revolutionize disease treatment and contribute to significant advancements in the biomedical field.

Chemically Modified Platforms for Better RNA Therapeutics

RNA-based therapies have catalyzed a revolutionary transformation in the biomedical landscape, offering unprecedented potential in disease prevention and treatment. However, despite their remarkable achievements, these therapies encounter substantial challenges including low stability, susceptibility to degradation by nucleases, and a prominent negative charge, thereby hindering further development. Chemically modified platforms have emerged as a strategic innovation, focusing on precise alterations either on the RNA moieties or their associated delivery vectors. This comprehensive review delves into these platforms, underscoring their significance in augmenting the performance and translational prospects of RNA-based therapeutics. It encompasses an in-depth analysis of various chemically modified delivery platforms that have been instrumental in propelling RNA therapeutics toward clinical utility. Moreover, the review scrutinizes the rationale behind diverse chemical modification techniques aiming at optimizing the therapeutic efficacy of RNA molecules, thereby facilitating robust disease management. Recent empirical studies corroborating the efficacy enhancement of RNA therapeutics through chemical modifications are highlighted. Conclusively, we offer profound insights into the transformative impact of chemical modifications on RNA drugs and delineates prospective trajectories for their future development and clinical integration.

Simvastatin nanocrystals-based dissolving microneedles for wound healing

Currently, one of the main problems encountered in wound healing therapy is related to inefficient drug delivery. However, dissolving microneedles (DMNs) can be administered percutaneously to effectively deliver a drug to a deep wound area. Simvastatin (SIM) can promote wound healing, albeit its insolubility in water limits its application. Here, we designed a DMNs (SIM-NC@DMNs) drug delivery system loaded with SIM nanocrystals (SIM-NC) and evaluated its efficacy in wound healing. Based on our observations, the dissolution performance of insoluble SIM is significantly improved after the preparation of SIM-NC. For example, the saturation solubility of SIM-NC in deionized water and PBS increased by 150.57 times and 320.14 times, respectively. After the SIM-NC@DMNs are deeply inserted into the wound, the needle portion, which is composed of hyaluronic acid (HA), dissolves rapidly, and the SIM-NC loaded on the needle portion is efficiently released into the deep wound area for optimal therapeutic efficacy. The combination of NC and DMNs makes this system further effective for wound healing. Our cumulative work suggests that the newly developed SIM-NC@DMNs possess great potential in accelerating wound healing. By day 12 after treatment, the residual wound area in the Control group was 21.34 %, while the residual wound area in the SIM-NC@DMNs group was only 2.36 %. This result as well as provides certain evidence of its efficacy for wound healing therapy. The SIM-NC@DMNs drug delivery system may become an efficient treatment modality that promotes wound healing, with a promising potential in the field of wound healing research.

Multifunctional lipid-based nanoparticles for wound healing and antibacterial applications: A review

Wound healing primarily involves preventing severe infections, accelerating healing, and reducing pain and scarring. Therefore, the multifunctional application of lipid-based nanoparticles (LBNs) has received considerable attention in drug discovery due to their solid or liquid lipid core, which increases their ability to provide prolonged drug release, reduce treatment costs, and improve patient compliance. LBNs have also been used in medical and cosmetic practices and formulated for various products based on skin type, disease conditions, administration product costs, efficiency, stability, and toxicity; therefore, understanding their interaction with biological systems is very important. Therefore, it is necessary to perform an in-depth analysis of the results from a comprehensive characterization process to produce lipid-based drug delivery systems with desired properties. This review will provide detailed information on the different types of LBNs, their formulation methods, characterisation, antimicrobial activity, and application in various wound models (both in vitro and in vivo studies). Also, the clinical and commercial applications of LBNs are summarized.

Protein-modified nanomaterials: emerging trends in skin wound healing

Prolonged inflammation can impede wound healing, which is regulated by several proteins and cytokines, including IL-4, IL-10, IL-13, and TGF-β. Concentration-dependent effects of these molecules at the target site have been investigated by researchers to develop them as wound-healing agents by regulating signaling strength. Nanotechnology has provided a promising approach to achieve tissue-targeted delivery and increased effective concentration by developing protein-functionalized nanoparticles with growth factors (EGF, IGF, FGF, PDGF, TGF-β, TNF-α, and VEGF), antidiabetic wound-healing agents (insulin), and extracellular proteins (keratin, heparin, and silk fibroin). These molecules play critical roles in promoting cell proliferation, migration, ECM production, angiogenesis, and inflammation regulation. Therefore, protein-functionalized nanoparticles have emerged as a potential strategy for improving wound healing in delayed or impaired healing cases. This review summarizes the preparation and applications of these nanoparticles for normal or diabetic wound healing and highlights their potential to enhance wound healing.

Low-dose rosmarinic acid and thymoquinone accelerate wound healing in retinal pigment epithelial cells

PURPOSE

Thymoquinone (TQ) and rosmarinic acid (RA) are two biologically active compounds found in plants and that possess remarkable anti-oxidant and anti-inflammatory properties. The present study aimed to investigate the potential protective effects of RA and TQ, which have known anti-inflammatory and anti-oxidant effects, on retinal damage by establishing a wound healing model for retinal pigment epithelial cells (ARPE-19).

METHOD

To this end, IC50 doses of RA and TQ in ARPE-19 cells were calculated by MTT assay. Both agents were administered at IC50, IC50/2 and IC50/4 doses for wound healing assay, and wound closure percentages were analyzed. Since the best wound healing was found at IC50/4 dose (low dose) for both agents, other biochemical and molecular analyses were planned to be performed using these doses. Following low dose RA and TQ treatments, the cells were lysed and TGF-β1 and MMP-9 levels were analyzed by ELISA technique from the cell lysates obtained. In addition, the mRNA expression levels of TLR3, IFN-γ and VEGF were calculated by RT-PCR technique.

RESULTS

Low dose of RA and TQ dramatically increased wound healing. RA may have achieved this by increasing levels of MMP-9 and TLR-3. In contrast, the mRNA expression level of VEGF remained unchanged. TQ accelerated wound healing by increasing both the protein levels of TGF-β1 and MMP-9. Furthermore, low dose of TQ decreased both TLR3 and IFN-γ mRNA expression levels.

CONCLUSION

Low doses of RA and TQ were clearly demonstrated to have protective properties against possible damage to retinal pigment epithelial cells.

Solid Lipid Nanoparticles vs. Nanostructured Lipid Carriers: A Comparative Review

Solid-lipid nanoparticles and nanostructured lipid carriers are delivery systems for the delivery of drugs and other bioactives used in diagnosis, therapy, and treatment procedures. These nanocarriers may enhance the solubility and permeability of drugs, increase their bioavailability, and extend the residence time in the body, combining low toxicity with a targeted delivery. Nanostructured lipid carriers are the second generation of lipid nanoparticles differing from solid lipid nanoparticles in their composition matrix. The use of a liquid lipid together with a solid lipid in nanostructured lipid carrier allows it to load a higher amount of drug, enhance drug release properties, and increase its stability. Therefore, a direct comparison between solid lipid nanoparticles and nanostructured lipid carriers is needed. This review aims to describe solid lipid nanoparticles and nanostructured lipid carriers as drug delivery systems, comparing both, while systematically elucidating their production methodologies, physicochemical characterization, and in vitro and in vivo performance. In addition, the toxicity concerns of these systems are focused on.

Therapeutic role of growth factors in treating diabetic wound

Wounds in diabetic patients, especially diabetic foot ulcers, are more difficult to heal compared with normal wounds and can easily deteriorate, leading to amputation. Common treatments cannot heal diabetic wounds or control their many complications. Growth factors are found to play important roles in regulating complex diabetic wound healing. Different growth factors such as transforming growth factor beta 1, insulin-like growth factor, and vascular endothelial growth factor play different roles in diabetic wound healing. This implies that a therapeutic modality modulating different growth factors to suit wound healing can significantly improve the treatment of diabetic wounds. Further, some current treatments have been shown to promote the healing of diabetic wounds by modulating specific growth factors. The purpose of this study was to discuss the role played by each growth factor in therapeutic approaches so as to stimulate further therapeutic thinking.

Recent Advances in Nano-Drug Delivery Systems for the Treatment of Diabetic Wound Healing

Diabetes mellitus (DM) induced wound healing impairment remains a serious health problem and burden on the clinical obligation for high amputation rates. Based on the features of wound microenvironment, biomaterials loading specific drugs can benefit diabetic wound treatment. Drug delivery systems (DDSs) can carry diverse functional substances to the wound site. Nano-drug delivery systems (NDDSs), benefiting from their features related to nano size, overcome limitations of conventional DDSs application and are considered as a developing process in the wound treatment field. Recently, a number of finely designed nanocarriers efficiently loading various substances (bioactive and non-bioactive factors) have emerged to circumvent constraints faced by traditional DDSs. This review describes various recent advances of nano-drug delivery systems involved in mitigating diabetes mellitus-based non-healing wounds.