Prussian blue nanozymes coated with Pluronic attenuate inflammatory osteoarthritis by blocking c-Jun N-terminal kinase phosphorylation

Exosome-Functionalized Self-Carrier Enzyme-Like/Drug With Triple Amplified Anti-Oxidative Stress for Synergistic Depression Therapy

Depression, a severe disorder affecting both physical and mental health, is commonly treated with first-line antidepressants, which often exhibit limited efficacy due to poor penetration of the blood-brain barrier (BBB) and significant side effects, thus requiring the exploitation of biocompatible and effective treatments. Recent studies suggest that depression is closely linked to an imbalance in oxidative stress and subsequent inflammatory responses. Antioxidant therapies and targeting oxidative stress in inflammatory depression are therefore emerging as promising strategies. In this study, an exosome-functionalized and geniposide (GEN) self-carried Prussian blue (PB) nanotherapeutic approach is fabricated to realize efficient BBB penetration for synergistic depression therapy. The porous PB carrier possesses multi-enzyme capabilities, which can effectively scavenge the accumulated ROS, protecting the slightly inflammatory acidic environment released GEN from oxidation, and the GEN subsequently works simultaneously with PB to activate the Nrf2-ARE pathway, enhancing the body's oxidative stress defense mechanisms synergistically. The triple-amplified anti-oxidant strategy of this nanomaterial is shown to mitigate microglial activation and the reduction in neuroplasticity, ultimately alleviating the pathological markers of inflammatory depression. Overall, the constructed nanomaterials underscore the therapeutic potential of anti-oxidative stress for synergistic removal of ROS and activation of the Nrf2-ARE pathway in the treatment of inflammatory depression.

Nanoenzyme-Anchored Mitofactories Boost Mitochondrial Transplantation to Restore Locomotor Function after Paralysis Following Spinal Cord Injury

Mitochondrial transplantation is a significant therapeutic approach for addressing mitochondrial dysfunction in patients with spinal cord injury (SCI), yet it is limited by rapid mitochondrial deactivation and low transfer efficiency. Here, high-quality mitochondria microfactories (HQ-Mitofactories) were constructed by anchoring Prussian blue nanoenzymes onto mesenchymal stem cells for effective mitochondrial transplantation to treat paralysis from SCI. Notably, the results demonstrated that HQ-Mitofactories could continuously produce vitality-boosting mitochondria with highly interconnected and elongated network structures under oxidative stress by scavenging excessive ROS. Furthermore, HQ-Mitofactories enabled efficient transfer of therapeutic mitochondria to injured neurons primarily via gap junctions, resulting in the restoration of mitochondrial homeostasis and thereby suppressing intracellular ROS burst and facilitating neuronal repair. After i.v. administration, HQ-Mitofactories migrated to the injured spinal cords of SCI mice and subsequently promoted neuronal regeneration and remyelination. Consequently, HQ-Mitofactory-treated mice successfully recovered locomotor function within 4 weeks, with 40% of the mice fully restoring walking after hindlimb paralysis. Conversely, untreated SCI exhibited completely abolished hindlimb movements. In light of real-time generation of vitality-boosting mitochondria even under oxidative stress and enabling targeted mitochondrial transfer, HQ-Mitofactories have promising therapeutic potential in the context of mitochondrial transplantation to reduce SCI-related paralysis, and more broadly impact the field of neuroregenerative medicine.

Dual-sided centripetal microgrooved poly (D,L-lactide-co-caprolactone) disk encased in immune-regulating hydrogels for enhanced bone regeneration

Well-designed artificial scaffolds are urgently needed due to the limited self-repair capacity of bone, which hampers effective regeneration in critical defects. Optimal scaffolds must provide physical guidance to recruit cells and immune regulation to improve the regenerative microenvironment. This study presents a novel scaffold composed of dual-sided centripetal microgrooved poly(D,L-lactide-co-caprolactone) (PLCL) film combined with a dynamic hydrogel containing prednisolone (PLS)-loaded Prussian blue nanoparticles (PB@PLS). The microgrooves on the surface of the PLCL film were imprinted using a micropatterned polydimethylsiloxane (PDMS) template. Following aminolysis, the PLCL film was covalently grafted with the EM-7 peptide via glutaraldehyde. Functional group analysis, surface morphology and hydrophilicity were evaluated using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and an optical contact angle measuring instrument, respectively. Bone regeneration-related cells (e.g., bone marrow mesenchymal stem cells, macrophages, Schwann cells, and endothelial cells) cultured on PLCL films tended to align along the stripes and migrate from the periphery toward the center region in vitro. Subsequently, the PLCL film was encapsulated in an immune-regulating hydrogel synthesized from thiol-modified gelatin and Cu2+ in the presence of PB@PLS nanoparticles, which demonstrated excellent antioxidant properties. This scaffold significantly accelerated critical-sized bone regeneration, as evidenced by an increase in the volume of newly formed bone and histological images in vivo. This innovative approach holds substantial promise for clinical applications in bone regeneration and broader tissue repair.

Nanozyme-based therapeutic strategies for rheumatoid arthritis

Rheumatoid arthritis (RA) is a prevalent chronic autoimmune disease that leads to severe joint damage and disability. Conventional treatment options are limited by their efficacy and side effect profiles. Nanozymes, nanomaterials with enzyme-like activities, offer a novel therapeutic approach for RA. This review summarizes recent advances in nanozyme-based treatments, focusing on their antioxidant and immunomodulatory roles in mitigating RA. We discuss various nanozymes, including those based on cerium, iron, manganese, silver, copper, platinum, rhodium, and multi-metallic nanozymes, which mimic natural enzymes such as superoxide dismutase, catalase, and peroxidase to reduce oxidative stress. Additionally, we explore nanozyme-based combination therapies that integrate with other strategies, such as vesicles and phototherapy, to achieve synergistic effects and enhance efficacy. This review highlights the significant potential of nanozymes in improving RA treatment, offering a new perspective for future research and clinical applications.

Lubricating and Dual-Responsive Injectable Hydrogels Formulated From ZIF-8 Facilitate Osteoarthritis Treatment by Remodeling the Microenvironment

Osteoarthritis (OA) is a progressively developing condition primarily characterized by the deterioration of articular cartilage and the proliferation of bone, along with ongoing inflammation. Although the precise pathogenesis remains somewhat elusive, restoring the homeostatic balance of the intra-articular microenvironment is crucial for the management of OA. Intra-articular injection of medication is one of the most direct and effective treatment methods; however, most injectable drugs used for osteoarthritis treatment, due to their rapid breakdown, quick release, poor biological activity, and frequent injections, leading to increased risk of infection and suboptimal therapeutic outcomes. In this study, a lubricating and dual-responsive injectable hydrogel based on zeolitic imidazolate frameworks-8 (ZIF-8) impregnated with Quercetin (Que) is designed, which can facilitate OA treatment by remodeling the microenvironment. The prepared injectable nanocomposite hydrogel (MH/CCM@ZIF-8@Que) exhibits pH and reactive oxygen species (ROS) responsiveness, alongside a controllable release of bioactive substances to modulate the microenvironment of bone tissue, thereby mitigating synovitis and the degeneration of cartilage matrix, while simultaneously facilitating cartilage repair. This developed thermosensitive injectable hydrogel, which effectively balances lubrication with the controlled release of bioactive substances, represents a highly promising therapeutic approach for osteoarthritis.

Screening of potential biomarkers of osteoarthritis: a bioinformatics analysis

BACKGROUND

Osteoarthritis (OA) is the most common joint disease worldwide, with an age-associated increasing in both incidence and prevalence. However, early diagnosis of OA is a challenge due to the lack of effective biomarkers. This study aimed to identify new biomarkers and mechanisms of OA.

METHODS

Microarray expression data of synovial tissues from osteoarthritic and healthy populations were downloaded from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were identified using GEO2R. Functions and enrichment pathways of DEGs were explained by enrichment analysis and construction of protein-protein interaction (PPI) networks, and hub genes were identified.

RESULTS

By performing Venn analysis on the DEGs obtained from the two datasets, 28 upregulated and 84 downregulated DEGs were gained. JUN, activating transcription factor 3 (ATF3), and Dual-specificity phosphatase 1 (DUSP1), which play important roles in OA, were screened using PPI network construction. The receiver operating characteristic (ROC) curve of JUN, ATF3, and DUSP1 revealed satisfactory diagnostic value for OA. hsa-mir-26b-5p interacts with JUN, ATF3, and DUSP1.

CONCLUSION

The expression of JUN, ATF3, and DUSP1 was reduced in patients with OA and the three genes mentioned above could be used as potential markers for the diagnosis of OA. hsa-mir-26b-5p may play an important role in the pathogenesis of OA and may be a potential therapeutic target. Key Points • JUN, ATF3, and DUSP1 could be used as potential markers for the diagnosis of OA. • hsa-mir-26b-5p may play an important role in the pathogenesis of OA.

Development of a Dual-Readout Multicolor Immunoassay for the Rapid Analysis of Isocarbophos in Vegetable and Fruit Samples

Multicolor immunoassay is a powerful tool for rapid analysis without the use of bulky instruments owing to various color conversions, which is suitable for on-site visual analysis for pesticides. Herein, this study developed a multicolor immunoassay for the rapid detection of isocarbophos. After competitive immunoassay, the secondary antibody (GAM-ALP) catalyzed ascorbyl-2-phosphate (AAP) into ascorbic acid (AA). The AA can reduce K3[Fe(CN)6] into K4[Fe(CN)6]. The latter can react with Fe3+ to form Prussian blue; otherwise, the orange AAP-Fe3+ complex was generated. Therefore, the multicolor immunoassay achieved a color conversion of orange-green-blue in response to isocarbophos, allowing for rapid semiquantitative analysis by the naked eye. After parameter optimization, the multicolor immunoassay was developed depending on the ratiometric absorbance between the Prussian blue and AAP-Fe3+ complex. Moreover, a smartphone was used to measure the RGB value of the color conversion for the development of portable visual, quantitative analysis. Both the absorbance-based and RGB-based multicolor immunoassays showed good accuracy and practicability in the recovery test. This study provided a common approach for the development of dual-readout multicolor immunoassay, which can be used for on-site rapid screening by quantitative or visual semiquantitative analysis.

Prussian blue nanotechnology in the treatment of spinal cord injury: application and challenges

Spinal cord injury (SCI) is a serious neurological condition that currently lacks effective treatments, placing a heavy burden on both patients and society. Prussian blue nanoparticles exhibit great potential for treating spinal cord injuries due to their excellent physicochemical properties and biocompatibility. These nanoparticles have strong anti-inflammatory and antioxidant capabilities, effectively scavenge free radicals, and reduce oxidative stress damage to cells. Prussian blue nanotechnology shows broad application potential in drug delivery, bioimaging, cancer therapy, anti-inflammatory and oxidative stress treatment, and biosensors. This article reviewed the potential applications of Prussian blue nanotechnology in treating spinal cord injuries, explored the challenges and solutions associated with its application, and discussed the future prospects of this technology in SCI treatment.

Microenvironment-sensitive nanozymes for tissue regeneration

Tissue defect is one of the significant challenges encountered in clinical practice. Nanomaterials, including nanoparticles, nanofibers, and metal-organic frameworks, have demonstrated an extensive potential in tissue regeneration, offering a promising avenue for future clinical applications. Nonetheless, the intricate landscape of the inflammatory tissue microenvironment has engendered challenges to the efficacy of nanomaterial-based therapies. This quandary has spurred researchers to pivot towards advanced nanotechnological remedies for overcoming these therapeutic constraints. Among these solutions, microenvironment-sensitive nanozymes have emerged as a compelling instrument with the capacity to reshape the tissue microenvironment and enhance the intricate process of tissue regeneration. In this review, we summarize the microenvironmental characteristics of damaged tissues, offer insights into the rationale guiding the design and engineering of microenvironment-sensitive nanozymes, and explore the underlying mechanisms that underpin these nanozymes' responsiveness. This analysis includes their roles in orchestrating cellular signaling, modulating immune responses, and promoting the delicate process of tissue remodeling. Furthermore, we discuss the diverse applications of microenvironment-sensitive nanozymes in tissue regeneration, including bone, soft tissue, and cartilage regeneration. Finally, we shed our sights on envisioning the forthcoming milestones in this field, prospecting a future where microenvironment-sensitive nanozymes contribute significantly to the development of tissue regeneration and improved clinical outcomes.

A Novel BD2-Selective Inhibitor of BRDs Mitigates ROS Production and OA Pathogenesis

Bromodomain and extra-terminal domain (BET) family proteins regulate transcription and recognize lysine residues in histones. Selective BET inhibitors targeting one domain have attracted attention because they maintain normal physiological activities, whereas pan (nonselective) BET inhibitors do not. Osteoarthritis (OA) is a joint disorder characterized by cartilage degeneration for which no treatment currently exists. Here, we investigated whether the selective inhibition of BET proteins is an appropriate therapeutic strategy for OA. We focused on the development and characterization of 2-(4-(2-(dimethylamino)ethoxy)-3,5-dimethylphenyl)-5,7-dimethoxyquinazolin-4(3H)-one (BBC0906), a novel bromodomain 2 (BD2)-specific inhibitor designed to suppress OA progression. Using a DNA-encoded chemical library (DEL) screening approach, BBC0906 was identified because of its high affinity with the BD2 domain of BET proteins. BBC0906 effectively reduced reactive oxygen species (ROS) production and suppressed catabolic factor expression in chondrocytes in vitro. Moreover, in an OA mouse model induced by the destabilization of the medial meniscus (DMM), BBC0906 intra-articular injection attenuated cartilage degradation and alleviated OA. Importantly, BBC0906 selectively inhibits the BD2 domain, thus minimizing its potential side effects. We highlighted the therapeutic potential of targeting BET proteins to modulate oxidative stress and suppress cartilage degradation in OA. BBC0906 is a promising candidate for OA treatment, offering improved safety and efficacy.

Tisochrysis lutea Fucoxanthin Suppresses NF-κB, JNK, and p38-Associated MMP Expression in Arthritis Pathogenesis via Antioxidant Activity

Tisochrysis lutea is a highly nutritious marine microalga that has various applications in aquaculture and biotechnology. However, the effects of T. lutea extract (TLE) on osteoarthritis (OA) pathogenesis remain unexplored. In this study, we aimed to determine the effects of TLE on OA development. We found that TLE inhibits the expression of matrix metalloproteinases (MMPs) and reactive oxygen species (ROS) activity in an OA mouse model generated by the destabilization of the medial meniscus (DMM) surgery. In vivo assays of the OA model mice demonstrated that TLE has a protective effect against cartilage destruction by inhibiting MMP3 and MMP13 expression. To enable the medical use of TLE, the components of TLE were characterized using high-performance liquid chromatography (HPLC) analysis. Interestingly, we found that Fucoxanthin accounts for 41.2% of TLE and showed anti-catabolic and antioxidant effects under IL-1β-treated in vitro conditions. RNA sequencing analysis showed that fucoxanthin decreased p38, NF-κB, and JNK signaling pathway gene expression, all of which are activated by IL-1β. Furthermore, in vivo analysis showed that fucoxanthin inhibited the IL-1β-stimulated phosphorylation of p65, JNK, and p38. These results highlight new possibilities for the use of TLE as a source of fucoxanthin, an antioxidant, for OA treatment.

BRD2-specific inhibitor, BBC0403, inhibits the progression of osteoarthritis pathogenesis in osteoarthritis-induced C57BL/6 male mice

BACKGROUND AND PURPOSE

The discovery of new bromo- and extra-terminal inhibitors presents new drugs to treat osteoarthritis (OA).

EXPERIMENTAL APPROACH

The new drug, BBC0403, was identified in the DNA-encoded library screening system by searching for compounds that target BRD (bromodomain-containing) proteins. The binding force with BRD proteins was evaluated using time-resolved fluorescence energy transfer (TR-FRET) and binding kinetics assays. Subsequently, in vitro and ex vivo analyses demonstrated the effects of the BRD2 inhibitor, BBC0403, on OA. For animal experiments, medial meniscus destabilization was performed to create a 12-week-old male C57BL/6 mouse model, and intra-articular (i.a.) injections were administered. Histological and immunohistochemical analyses were then performed. The underlying mechanism was confirmed by gene set enrichment analysis (GSEA) using RNA-seq.

KEY RESULTS

TR-FRET and binding kinetics assays revealed that BBC0403 exhibited higher binding specificity for BRD2 compared to BRD3 and BRD4. The anti-OA effects of BBC0403 were tested at concentrations of 5, 10 and 20 μM (no cell toxicity in the range tested). The expression of catabolic factors, prostaglandin E2 (PGE2) production and extracellular matrix (ECM) degradation was reduced. Additionally, the i.a. injection of BBC0403 prevented OA cartilage degradation in mice. Finally, BBC0403 was demonstrated to suppress NF-κB and MAPK signalling pathways.

CONCLUSION AND IMPLICATIONS

This study demonstrated that BBC0403 is a novel BRD2-specific inhibitor and a potential i.a.-injectable therapeutic agent to treat OA.

Nano-enzyme hydrogels for cartilage repair effectiveness based on ternary strategy therapy

Designing artificial nano-enzymes for scavenging reactive oxygen species (ROS) in chondrocytes (CHOs) is considered the most feasible pathway for the treatment of osteoarthritis (OA). However, the accumulation of ROS due to the amount of nano-enzymatic catalytic site exposure and insufficient oxygen supply seriously threatens the clinical application of this therapy. Although metal-organic framework (MOF) immobilization of artificial nano-enzymes to enhance active site exposure has been extensively studied, artificial nano-enzymes/MOFs for ROS scavenging in OA treatment are still lacking. In this study, a biocompatible lubricating hydrogel-loaded iron-doped zeolitic imidazolate framework-8 (Fe/ZIF-8/Gel) centrase was engineered to scavenge endogenous overexpressed ROS synergistically generating dissolved oxygen and enhancing sustained lubrication for CHOs as a ternary artificial nano-enzyme. This property enabled the nano-enzymatic hydrogels to mitigate OA hypoxia and inhibit oxidative stress damage successfully. Ternary strategy-based therapies show excellent cartilage repair in vivo. The experimental results suggest that nano-enzyme-enhanced lubricating hydrogels are a potentially effective OA treatment and a novel strategy.

WGA-M001, a Mixture of Total Extracts of Tagetes erecta and Ocimum basilicum, Synergistically Alleviates Cartilage Destruction by Inhibiting ERK and NF-κB Signaling

Tagetes erecta and Ocimum basilicum are medicinal plants that exhibit anti-inflammatory effects against various diseases. However, their individual and combined effects on osteoarthritis (OA) are unknown. Herein, we aimed to demonstrate the effects of T. erecta, O. basilicum, and their mixture, WGA-M001, on OA pathogenesis. The administration of total extracts of T. erecta and O. basilicum reduced cartilage degradation and inflammation without causing cytotoxicity. Although WGA-M001 contained lower concentrations of the individual extracts, it strongly inhibited the expression of pathogenic factors. In vivo OA studies also supported that WGA-M001 had protective effects against cartilage destruction at lower doses than those of T. erecta and O. basilicum. Moreover, its effects were stronger than those observed using Boswellia and Perna canaliculus. WGA-M001 effectively inhibited the interleukin (IL)-1β-induced nuclear factor kappa-light-chain-enhancer of the activated B cell (NF-κB) pathway and ERK phosphorylation. Furthermore, RNA-sequence analysis also showed that WGA-M001 decreased the expression of genes related to the IL-1β-induced NF-κB and ERK signaling pathways. Therefore, WGA-M001 is more effective than the single total extracts of T. erecta and O. basilicum in attenuating OA progression by regulating ERK and NF-κB signaling. Our results open new possibilities for WGA-M001 as a potential therapeutic agent for OA treatment.

The management of osteoarthritis symptomatology through nanotechnology: a patent review

Osteoarthritis is considered a degenerative joint disease that is characterised by inflammation, chronic pain, and functional limitation. The increasing development of nanotechnology in drug delivery systems has provided new ideas and methods for osteoarthritis therapy. This review aimed to evaluate patents that have developed innovations, therapeutic strategies, and alternatives using nanotechnology in osteoarthritis treatment. The results show patents deposited from 2015 to November 2021 in the online databases European Patent Office and World Intellectual Property Organisation. A total of 651 patents were identified for preliminary assessment and 16 were selected for full reading and discussion. The evaluated patents are focused on the intraarticular route, oral route, and topical route for osteoarthritis treatment. The intraarticular route presented a higher patent number, followed by the oral and topical routes, respectively. The development of new technologies allows us to envision a promising and positive future in osteoarthritis treatment.

Polymeric biomaterials: Advanced drug delivery systems in osteoarthritis treatment

Polymeric biomaterials have emerged as a highly promising candidate for drug delivery systems (DDS), exhibiting significant potential to enhance the therapeutic landscape of osteoarthritis (OA) therapy. Their remarkable capacity to manifest desirable physicochemical attributes, coupled with their excellent biocompatibility and biodegradability, has greatly expanded their utility in pharmacotherapeutic applications. Nevertheless, an urgent necessity exists for a comprehensive synthesis of the most recent advances in polymeric DDS, providing valuable guidance for their implementation in the context of OA therapy. This review is dedicated to summarizing and examining recent developments in the utilization of polymeric DDS for OA therapy. Initially, we present an overview of the intricate pathophysiology characterizing OA and underscore the prevailing limitations inherent to current treatment modalities. Subsequently, we introduce diverse categories of polymeric DDS, including hydrogels, nanofibers, and microspheres, elucidating their inherent advantages and limitations. Moreover, we discuss and summarize the delivery of bioactive agents through polymeric biomaterials for OA therapy, emphasizing key findings and emerging trends. Finally, we highlight prospective directions for advancing polymeric DDS, offering a promising approach to enhance their translational potential for OA therapy.

Novel molecule BBC0901 inhibits BRD4 and acts as a catabolic regulator in the pathogenesis of osteoarthritis

Osteoarthritis (OA) is induced by matrix degradation and inflammation mediated by bromo-domain-containing protein 4 (BRD4)-dependent catabolic factors. BRD4 acts as both a transcriptional regulator and an epigenetic reader. BBC0901 was identified as an inhibitor of BRD4 using a DNA-encoded library screening system. We aimed to demonstrate the effects of BBC0901 on OA pathogenesis by in vitro, ex vivo, and in vivo analyses. BBC0901 inhibited the expression of catabolic factors that degrade cartilage without significantly affecting the viability of mouse articular chondrocytes. Additionally, ex vivo experiments under conditions mimicking OA showed that BBC0901 suppressed extracellular matrix degradation. RNA sequencing analysis of gene expression patterns showed that BBC0901 inhibited the expression of catabolic factors, such as matrix metalloproteinases (MMPs) and cyclooxygenase (COX)2, along with reactive oxygen species (ROS) production. Furthermore, intra-articular (IA) injection of BBC0901 into the knee joint blocked osteoarthritic cartilage destruction by inhibition of MMP3, MMP13, COX2, interleukin (IL)6, and ROS production, thereby obstructing the nuclear factor kappa-light-chain-enhancer of activated B cell and mitogen activated protein kinase signaling. In conclusion, BBC0901-mediated BRD4 inhibition prevented OA development by attenuating catabolic signaling and hence, can be considered a promising IA therapeutic for OA.