Transcutaneous Immunotherapy for RNAi: A Cascade-Responsive Decomposable Nanocomplex Based on Polyphenol-Mediated Framework Nucleic Acid in Psoriasis

A Binary siRNA-Loaded Tetrahedral DNA Nanobox for Synergetic Anti-Aging Therapy

Extensive accumulation of senescent cells contributes to organismal aging, and slowing down the process of cellular senescence may ameliorate age-related pathologies. Targeted inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) is found to suppress the conversion of cells to senescence. The regulatory-associated protein of mTOR (Raptor), a key component of mTORC1, has been implicated as important in the aging process, and its druggability deserves to be investigated. Due to high efficiency and high convenience in drug construction, siRNA shows great potential in silencing Raptor expression via RNA interfering therapy. Here, we developed a functionalized anti-aging nanoplatform based on tetrahedral DNA nanostructures (TDNs) encapsulating siRNA targeting Raptor for synergistic anti-aging therapy, named siR-TDNbox. Anti-inflammatory and antioxidant properties of TDN beneficially attenuate age-associated inflammation while serving as siRNA nanocarrier, and thus play a binary role. The results suggest that the siR-TDNbox binary therapeutic nanoplatform has demonstrated an excellent ability to delay aging, inhibit mTORC1 signaling, and extend lifespan. This anti-aging nanoplatform may provide a medium for the combined application of traditional senotherapeutic drugs and promote the upgrading of nanomaterials with anti-aging effects.

A Multifunctional Nanocomplex as miRNA/Antibiotic Co-Delivery System Based on Tetrahedral Framework DNA: Application to Infected Wound Healing

Infected wounds are a complex disease involving bacterial infections and dysregulated inflammation. However, current research has mostly focused on bacterial inhibition rather than on inflammation. Thus, combined therapeutic strategies with anti-bacterial and anti-inflammation efficacies are urgently needed. Antibiotics are the main treatment strategy for infections. However, the excessive use of antibiotics throughout the body can cause serious side effects. In addition, miRNA-based therapeutics are superior for the treatment of wounds, but their rapid degradation and poor cellular uptake limit their clinical application. Tetrahedral framework DNA (tFNA) is an ideal drug delivery system owing to its excellent stability and remarkable transport ability. Herein, a novel multi-functional miRNA and antibiotic co-delivery system based on tFNA is presented for the first time, called B/L. B/L has heightened resistance to serum and excellent codelivery ability. After transdermal administration, B/L can specifically target TNF receptor-associated factor 6(TRAF6) and IL-1receptor-associated kinase 1(IRAK1), thereby regulating nuclear factor kappa-B (NF-𝜿B) and thus effectively reducing inflammation and promoting the healing of infected wounds. This novel multi-functional co-delivery system provides a versatile, simple, biocompatible, and powerful platform for the personalized and combined treatment of multiple diseases.

Sele-targeted siRNA liposome nanoparticles inhibit pathological scars formation via blocking the cross-talk between monocyte and endothelial cells: a preclinical study based on a novel mice scar model

BACKGROUND

Pathological scars (PS) are one of the most common complications in patients with trauma and burns, leading to functional impairments and aesthetic concerns. Mechanical tension at injury sites is a crucial factor in PS formation. However, the precise mechanisms remain unclear due to the lack of reliable animal models.

RESULTS

We developed a novel mouse model, the Retroflex Scar Model (RSM), which induces PS by applying controlled tension to wounds in vivo. RNA sequencing identified significant transcriptome changes in RSM-induced scars. Elevated expression of E-Selectin (Sele) was observed in endothelial cells from both the RSM model and human PS (Keloid) samples. In vitro studies demonstrated that cyclic mechanical stretching (CMS) increased Sele expression, promoting monocyte adhesion and the release of pro-inflammatory factors. Single-cell sequencing analysis from the GEO database, complemented by Western blotting, immunofluorescence, and co-immunoprecipitation, confirmed the role of Sele-mediated monocyte adhesion in PS formation. Additionally, we developed Sele-targeted siRNA liposome nanoparticles (LNPs) to inhibit monocyte adhesion. Intradermal administration of these LNPs effectively reduced PS formation in both in vivo and in vitro studies.

CONCLUSIONS

This study successfully established a reliable mouse model for PS, highlighting the significant roles of mechanical tension and chronic inflammation in PS formation. We identified Sele as a key therapeutic target and developed Sele-targeted siRNA LNPs, which demonstrated potential as a preventive strategy for PS. These findings provide valuable insights into PS pathogenesis and open new avenues for developing effective treatments for pathological scars.

STAT3-specific nanocarrier for shRNA/drug dual delivery and tumor synergistic therapy

Non-small cell lung cancer (NSCLC) is a major disease with high incidence, low survival rate and prone to develop drug resistance to chemotherapy. The mechanism of secondary drug resistance in NSCLC chemotherapy is very complex, and studies have shown that the abnormal activation of STAT3 (Signal Transducer and Activator of Transcription 3) plays an important role in it. In this study, the pGPU6/GFP/Neo STAT3-shRNA recombinant plasmid was constructed with STAT3 as the precise target. By modifying hydrophilic and hydrophobic blocks onto chitosan, a multifunctional vitamin E succinate-chitosan-polyethylene glycol monomethyl ether histidine (VES-CTS-mPEG-His) micelles were synthesized. The micelles could encapsulate hydrophobic drug doxorubicin through self-assembly, and load the recombinant pGPU6/GFP/Neo STAT3-shRNA (pDNA) through positive and negative charges to form dual-loaded nanoparticles DOX/VCPH/pDNA. The co-delivery and synergistic effect of DOX and pDNA could up-regulate the expression of PTEN (Phosphatase and Tensin Homolog), down-regulate the expression of CD31, and induce apoptosis of tumor cells. The results of precision targeted therapy showed that DOX/VCPH/pDNA could significantly down-regulate the expression level of STAT3 protein, further enhancing the efficacy of chemotherapy. Through this study, precision personalized treatment of NSCLC could be effectively achieved, reversing its resistance to chemotherapy drugs, and providing new strategies for the treatment of drug-resistant NSCLC.

Therapeutic effects of tetrahedral framework nucleic acids and tFNAs-miR22 on retinal ischemia/reperfusion injury

Retinal ischemia/reperfusion injury (RI/R) is a common pathological process in ophthalmic diseases, which can cause severe visual impairment. The mechanisms underlying RI/R damage and repair are still unclear. Scholars are actively exploring effective intervention strategies to restore impaired visual function. With the development of nucleic acid nanomaterials, tetrahedral framework nucleic acids (tFNAs) have shown promising therapeutic potential in various fields such as stem cells, biosensors, and tumour treatment due to their excellent biological properties. Besides, miRNA-22-3p (miR-22), as an important regulatory factor in neural tissue, has been proven to have positive effects in various neurodegenerative diseases. By stably constructing a complex of tetrahedral framework nucleic acids miR22 (tFNAs-miR22), we observed that tFNAs-miR22 had a positive effect on the repair of RI/R injury in retinal neural tissue. Previous studies have shown that tFNAs can effectively deliver miR-22 into damaged retinal neurons, subsequently exerting neuroprotective effects. Interestingly, we found that there was a certain synergistic effect between tFNAs and miR-22. tFNAs-miR22 can selectively activated the ERK1/2 signalling pathway to reduce neuronal apoptosis, accelerate cell proliferation, and restore synaptic functional activity. In this study, we established a simple yet effective small molecule drug for RI/R treatment which may become a promising neuroprotectant for treating this type of vision impairment disease in the future.

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.

Stimuli-responsive drug delivery systems for inflammatory skin conditions

Inflammatory skin conditions highly influence the quality of life of the patients suffering from these disorders. Symptoms include red, itchy and painful skin lesions, which are visible to the rest of the world, causing stigmatization and a significantly lower mental health of the patients. Treatment options are often unsatisfactory, as they suffer from either low patient adherence or the risk of severe side effects. Considering this, there is a need for new treatments, and notably of new ways of delivering the drugs. Stimuli-responsive drug delivery systems are able to deliver their drug cargo in response to a given stimulus and are, thus, promising for the treatment of inflammatory skin conditions. For example, the use of external stimuli such as ultraviolet light, near infrared radiation, or alteration of magnetic field enables drug release to be precisely controlled in space and time. On the other hand, internal stimuli induced by the pathological condition, including pH alteration in the skin or upregulation of reactive oxygen species or enzymes, can be utilized to create drug delivery systems that specifically target the diseased skin to achieve a better efficacy and safety. In the latter context, however, it is of key importance to match the trigger mechanism of the drug delivery system to the actual pathological features of the specific skin condition. Hence, the focus of this article is placed not only on reviewing stimuli-responsive drug delivery systems developed to treat specific inflammatory skin conditions, but also on critically evaluating their efficacy in the context of specific skin diseases. STATEMENT OF SIGNIFICANCE: Skin diseases affect one-third of the world's population, significantly lowering the quality of life of the patients, who deal with symptoms such as painful and itchy skin lesions, as well as stigmatization due to the visibility of their symptoms. Current treatments for inflammatory skin conditions are often hampered by low patient adherence or serious drug side effects. Therefore, more emphasis should be placed on developing innovative formulations that provide better efficacy and safety for patients. Stimuli-responsive drug delivery systems hold considerable promise in this regard, as they can deliver their cargo precisely where and when it is needed, reducing adverse effects and potentially offering better treatment outcomes.

A bioswitchable delivery system for microRNA therapeutics based on a tetrahedral DNA nanostructure

As microRNAs (miRNA) regulate almost all physiopathological activities in the human body, miRNA therapeutics that deliver miRNA regulators have attracted considerable attention in the field of nucleic acid drug development. The use of tetrahedral DNA nanostructures to deliver miRNA regulators is promising because of their simple fabrication, enhanced cell entry, effective tissue penetration, biocompatibility and functional editability. This protocol extension builds on our previous protocol for the use of tetrahedral DNA nanostructures and was designed to establish an updated bioswitchable delivery system (BDS) for achieving controlled cargo loading and release. A ribonuclease H-sensitive sequence is designed as a bioswitchable apparatus for the targeted release of the miRNA regulator. The functional sequence of the miRNA regulator and minimal secondary structure formation tendency during annealing are two key points in cargo design. We provide two BDS design strategies; BDS-A comprises an intact DNA tetrahedron with the RNA cargo hanging outside, offering the merits of lower cost, simplicity, and more direct structural design. In the BDS-B design, the RNA regulators are embedded into the DNA tetrahedron, which is beneficial for dermal tissue permeation applications. Following sequence design in Oligo 7 and Tiamat, the BDS assembly is completed and then ribonuclease H achieves controlled release of the miRNA regulator by triggering the bioswitchable apparatus. This is verified via polyacrylamide and agarose gel electrophoresis or fluorophore modifications. Both BDSs show promising cellular membrane permeability, tissue permeability and target inhibition in vitro and in vivo. The assembly and characterization of the BDS can be completed in 4 d, and the validation time for biostability and biological applications will depend on the specific use.

A Bioswitchable MiRNA Delivery System: Tetrahedral Framework DNA-Based miRNA Delivery System for Applications in Wound Healing

The human body's primary line of defense, the skin, is especially prone to harm. Although microRNA (miRNA)-based therapies have attracted increasing attention for skin wound healing, their applications remain limited owing to a range of issues. Tetrahedral framework DNA (tFNA), a nanomaterial possessing nucleic acid characteristics, exhibits an excellent biocompatibility, in addition to anti-inflammatory and transdermal delivery capabilities, and can accelerate skin wound healing. Due to its potential to exert synergistic action with therapeutic miRNA, tFNA has been considered an ideal vehicle for miRNA therapy. The design and synthesis of a bioswitchable miRNA delivery system (BiRDS) is reported, which contains three miRNAs as well as a nucleic acid core to maximize the loading capacity while preserving the characteristics of tFNA. A high stability, excellent permeability of cells as well as tissues and good biological compatibility are demonstrated. By selectively inhibiting heparin-binding epidermal growth factor (HB-EGF), the BiRDS can inhibit the NF-κB pathway while simultaneously controlling the PTEN/Akt pathway. As a result, the BiRDS helps wound healing go through the inflammation to the proliferative phase. This study demonstrates the advantages of the BiRDS in miRNA-based therapy and provides new research ideas for the treatment of skin-related diseases.

Effect of tetrahedral framework nucleic acids on the reconstruction of tendon-to-bone injuries after rotator cuff tears

Clinicians and researchers have always faced challenges in performing surgery for rotator cuff tears (RCT) due to the intricate nature of the tendon-bone gradient and the limited long-term effectiveness. At the same time, the occurrence of an inflammatory microenvironment further aggravates tissue damage, which has a negative impact on the regeneration process of mesenchymal stem cells (MSCs) and eventually leads to the production of scar tissue. Tetrahedral framework nucleic acids (tFNAs), novel nanomaterials, have shown great potential in biomedicine due to their strong biocompatibility, excellent cellular internalisation ability, and unparalleled programmability. The objective of this research was to examine if tFNAs have a positive effect on regeneration after RCTs. Experiments conducted in a controlled environment demonstrated that tFNAs hindered the assembly of inflammasomes in macrophages, resulting in a decrease in the release of inflammatory factors. Next, tFNAs were shown to exert a protective effect on the osteogenic and chondrogenic differentiation of bone marrow MSCs under inflammatory conditions. The in vitro results also demonstrated the regulatory effect of tFNAs on tendon-related protein expression levels in tenocytes after inflammatory stimulation. Finally, intra-articular injection of tFNAs into a rat RCT model showed that tFNAs improved tendon-to-bone healing, suggesting that tFNAs may be promising tendon-to-bone protective agents for the treatment of RCTs.

Tetrahedral DNA loaded siCCR2 restrains M1 macrophage polarization to ameliorate pulmonary fibrosis in chemoradiation-induced murine model

Idiopathic pulmonary fibrosis (IPF) is a chronic lethal disease in the absence of demonstrated efficacy for preventing progression. Although macrophage-mediated alveolitis is determined to participate in myofibrotic transition during disease development, the paradigm of continuous macrophage polarization is still under-explored due to lack of proper animal models. Here, by integrating 2.5 U/kg intratracheal Bleomycin administration and 10 Gy thorax irradiation at day 7, we generated a murine model with continuous alveolitis-mediated fibrosis, which mimics most of the clinical features of our involved IPF patients. In combination with data from scRNA-seq of patients and a murine IPF model, a decisive role of CCL2/CCR2 axis in driving M1 macrophage polarization was revealed, and M1 macrophage was further confirmed to boost alveolitis in leading myofibroblast activation. Multiple sticky-end tetrahedral framework nucleic acids conjunct with quadruple ccr2-siRNA (FNA-siCCR2) was synthesized in targeting M1 macrophages. FNA-siCCR2 successfully blocked macrophage accumulation in pulmonary parenchyma of the IPF murine model, thus preventing myofibroblast activation and leading to the disease remitting. Overall, our studies lay the groundwork to develop a novel IPF murine model, reveal M1 macrophages as potential therapeutic targets, and establish new treatment strategy by using FNA-siCCR2, which are highly relevant to clinical scenarios and translational research in the field of IPF.