Synergistic Oxygen Generation and Reactive Oxygen Species Scavenging by Manganese Ferrite/Ceria Co-decorated Nanoparticles for Rheumatoid Arthritis Treatment

Upconversion nanoparticles-CuMnO2 nanoassemblies for NIR-excited imaging of reactive oxygen species in vivo

Here, we designed a ratiometric luminescent nanoprobe based on lanthanide-doped upconversion nanoparticles-CuMnO2 nanoassemblies for rapid and sensitive detection of reactive oxygen species (ROS) levels in living cells and mouse. CuMnO2 nanosheets exhibit a wide absorption range of 300-700 nm, overlapping with the visible-light emission of upconversion nanoparticles (UCNPs), resulting in a significant upconversion luminescence quenching. In an acidic environment, H2O2 can promote the redox reaction of CuMnO2, leading to its dissociation from the surface of UCNPs and the restoration of upconversion luminescence. The variation in luminescence intensity ratio (UCL475/UCL450) were monitored to detect ROS levels. The H2O2 nanoprobe exhibited a linear response in the range of 0.314-10 μM with a detection limit of 11.3 nM. The biological tests proved the excellent biocompatibility and low toxicity of obtained UCNPs-CuMnO2 nanoassemblies. This ratiometric luminescent nanoprobe was successfully applied for the detection of exogenous and endogenous ROS in live cells as well as in vivo ROS quantitation. The dual transition metal ions endow this probe efficient catalytic decomposition capabilities, and this sensing strategy broadens the application of UCNPs-based nanomaterials in the field of biological analysis and diagnosis.

Potential mechanisms of rheumatoid arthritis therapy: Focus on macrophage polarization

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that affects multiple organs and systems in the human body, often leading to disability. Its pathogenesis is complex, and the long-term use of traditional anti-rheumatic drugs frequently results in severe toxic side effects. Therefore, the search for a safer and more effective antirheumatic drug is extremely important for the treatment of RA. As important immune cells in the body, macrophages are polarized. Under pathological conditions, macrophages undergo proliferation and are recruited to diseased tissues upon stimulation. In the local microenvironment, they polarize into different types of macrophages in response to specific factors and perform unique functions and roles. Previous studies have shown that there is a link between macrophage polarization and RA, indicating that certain active ingredients can ameliorate RA symptoms through macrophage polarization. Notably, Traditional Chinese medicine (TCM) monomer component and compounds demonstrate a particular advantage in this process. Building upon this insight, we reviewed and analyzed recent studies to offer valuable and meaningful insights and directions for the development and application of anti-rheumatic drugs.

Fabrication of a novel macrophage-targeted biomimetic delivery composite hydrogel with multiple-sensitive properties for tri-modal combination therapy of rheumatoid arthritis

In this study, a porous polydopamine (PDA) nanoparticle-decorated β-glucan microcapsules (GMs) nanoplatform (PDA/GMs) were developed with macrophage-targeted biomimetic features and a carriers-within-carriers structure. Indocyanine green (ICG) and catalase (CAT) were subsequently co-encapsulated within the PDA/GMs to create a multifunctional nanotherapeutic agent, termed CIPGs. Furthermore, CIPGs and sinomenine (SIN) were co-loaded within a thermo-sensitive hydrogel to design an injectable delivery system, termed CIPG/SH, with potential for multi-modal therapy of rheumatoid arthritis (RA). Photothermal studies indicated that the CIPGs hold excellent photothermal conversion ability and thermal stability, as they combined the photothermal performance of both PDA and ICG. Meanwhile, the CIPGs displayed favorable oxygen self-supplying and photodynamic performance. The CIPGs showed near-infrared (NIR)-induced phototoxicity, effectively inhibiting macrophage proliferation and displaying remarkable antibacterial activity. In vitro drug release from the prepared CIPG/SH showed a controlled release pattern. Animal experiments conducted on an RA mice model confirmed that the formulated CIPG/SH exhibited significant therapeutic effects. By integrating the biological advantages, photothermal/photodynamic performance of the CIPGs, and controlled drug release performance of the thermo-sensitive hydrogels in a single delivery system, the prepared injectable CIPG/SH represents a novel versatile delivery system with great potential for multi-modal combination targeting therapy in RA.

Synergistic rheumatoid arthritis therapy by interrupting the detrimental feedback loop to orchestrate hypoxia M1 macrophage polarization using an enzyme-catalyzed nanoplatform

A detrimental feedback loop between hypoxia and oxidative stress consistently drives macrophage polarization toward a pro-inflammatory M1 phenotype, thus persistently aggravating rheumatoid arthritis (RA) progression. Herein, an enzyme-catalyzed nanoplatform with synergistic hypoxia-relieving and reactive oxygen species (ROS)-scavenging properties was developed using bovine serum albumin-bilirubin-platinum nanoparticles (BSA-BR-Pt NPs). Bilirubin was employed to eliminate ROS, while platinum exhibited a synergistic effect in scavenging ROS and simultaneously generated oxygen. In mice RA model, BSA-BR-Pt NPs treatment exhibited superior effects, resulting in significant improvements in joint inflammation, cartilage damage, and bone erosion, compared to methotrexate, the most widely used antirheumatic drug. Mechanistically, RNA-sequencing data and experimental results elucidated that BSA-BR-Pt NPs induced a re-polarization of hypoxic M1 macrophages to M2 macrophages via switching glycolysis to oxidative phosphorylation through the inhibition of HIF-1α pathway. Collectively, this research for the first time elaborated the underlying mechanism of enzyme-catalyzed nanoplatform in orchestrating macrophage polarization, and identified a novel therapeutic strategy for RA and other inflammatory disorders.

Preclinical studies of natural flavonoids in inflammatory bowel disease based on macrophages: a systematic review with meta-analysis and network pharmacology

Flavonoid is a category of bioactive polyphenolic compounds that are extensively distributed in plants with specific pharmacological properties, such as anti-inflammatory and anti-oxidant. Importantly, natural flavonoids have shown the protected function on the dextran sulfate sodium (DSS)-induced colitis in animals and lipopolysaccharides (LPS)-induced inflammatory response in macrophages. The purpose of this systematic review is to explore the efficacy of natural flavonoids in animal models of IBD (inflammatory bowel disease) and potential mechanisms in macrophages by meta-analysis and network pharmacology in preclinical studies. Relevant foundation studies were searched from January 2010 to November 2023 in databases like PubMed, Elsevier ScienceDirect, and Web of Science. Then, OriginPro software was used to extract values from images, and the analysis was performed using Review Manager 5.3. The retrieved data was analyzed according to the fixed-effects model and random-effects model. Subsequently, heterogeneity was evaluated using the I2 statistics. Lastly, network pharmacology was applied to confirm mechanisms of natural flavonoids on IBD. According to the results of meta-analysis, we found the natural flavonoids exhibited powerful therapeutic effects against IBD, which not only reversed colonic shortness (WMD = 1.33, 95% CI (1.07, 1.59), P < 0.00001), but also reduced histological score (SMD =  - 2.66, 95% CI (- 3.77, - 1.95), P < 0.00001) between natural flavonoid treatment groups compared with the experimental IBD model. Furthermore, treatment with natural flavonoids decreased the levels of tumor necrosis factor-α (TNF-α) in macrophages. Mechanistically, our summarized data substantiate that natural flavonoids alleviate LPS-induced M1 macrophage polarization, anti-oxidant, anti-inflammatory, maintain intestinal barrier, and inhibit the activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome in macrophages. Moreover, the results of network pharmacology also support this. This systematic review demonstrated the efficiency of natural flavonoids in treating IBD in preclinical research by meta-analysis and network pharmacology, which offered supporting evidence for clinical trial implementation. However, some limitations remain present, such as technique quality shortage, missed reports on account of negative results, failure to count sample size, and the risk of bias.

From ROS scavenging to boosted osseointegration: cerium-containing mesoporous bioactive glass nanoparticles functionalized implants in diabetes

Excessive production of reactive oxygen species (ROS) around titanium implants under diabetic conditions causes persistent inflammation, leading to poor osseointegration and even implant failure. Surface modification is an effective way to promote ROS clearance, alleviate inflammation, and stimulate bone formation. In this study, a multifunctional coating is fabricated by introducing cerium (Ce)-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) onto the titanium surface via an electrophoretic deposition method. The incorporation of Ce-MBGNs remarkably improves surface hydrophilicity by increasing the surface areas. The bioactive ions are appropriately released, thereby promoting mesenchymal stem cell proliferation and differentiation under diabetic conditions. The conversion between Ce(III) and Ce(IV) endows Ce-MBGNs coating with antioxidative nanoenzymes properties to scavenge diabetes-induced ROS, resulting in macrophage polarization towards the anti-inflammatory phenotype. The therapeutic effect of Ce-MBGNs-modified titanium implants is also verified in diabetic rats by inhibiting inflammatory responses and accelerating early osseointegration. Taken together, the findings reveal that the ROS-scavenging and immunomodulation activity of the Ce-MBGNs coating contributes to enhanced osseointegration, and provides a novel implant surface for diabetic patients.

Targeting Synovial Macrophages with Astaxanthin-Loaded Liposomes for Antioxidant Treatment of Osteoarthritis

Osteoarthritis (OA) is a chronic joint disease highly associated with an imbalance in the network of inflammatory factors and typically characterized by oxidative stress and cartilage damage. Moreover, the specificity of the joint structure makes it difficult for drugs to achieve good penetration and effective enrichment in the joint cavity. Therefore, therapeutic strategies that increase the specific targeting of drugs to inflammatory joint and incorporate antioxidative stress effects are important to improve the efficacy of OA. Here, we developed a folic acid-modified liposomal nanoparticle (AST@Lip-FA) loaded with the antioxidant astaxanthin (AST) to enhance the water solubility and stability of AST and to target the delivery of AST to the site of OA, leading to a significant improvement in therapeutic efficacy. In vitro experiments demonstrated that, due to the recognition by FA of the receptor folate receptor β on the surface of activated macrophages, the cellular uptake efficiency of AST@Lip-FA was increased. Meanwhile, intracellularly overexpressed inflammatory mediators such as reactive oxygen species and nitric oxide were efficiently removed by AST@Lip-FA. In addition, in the ACLT-induced OA mouse model, AST@Lip-FA was precisely enriched in the inflamed joints and achieved long-term retention, fully utilizing the anti-inflammatory, antioxidant, and cartilage-protecting effects of AST to effectively alleviate the progression of OA. In summary, AST@Lip-FA has an important prospect as a potential and effective therapeutic strategy for OA.

Nano-vibration exciter: Hypoxia-inducible factor 1 signaling pathway-mediated extracellular vesicles as bioactive glass substitutes for bone regeneration

Bioactive glasses (BG) play a vital role in angiogenesis and osteogenesis through releasing functional ions. However, the rapid ion release in the early stage will cause excessive accumulation of metal ions, which in turn leads to obvious cytotoxicity, long-term inflammation, and bone repair failure. Inspired by the vibration exciter, small extracellular vesicles (sEVs) obtained by treating mesenchymal stem cells with copper-doped bioactive glass (CuBG-sEVs), is prepared as a nano-vibration exciter. The nano-vibration exciter can convert the ion signals of CuBG into biochemical factor signals through hypoxia-inducible factor 1 (HIF-1) signaling pathway and its activated autophagy, so as to better exert the osteogenic activity of BG. The results showed that CuBG extracts could significantly improve the enrichment of key miRNAs and increase the yield of CuBG-sEVs by activating HIF-1 signaling pathway and its activated autophagy. Cell experiments showed that CuBG-sEVs are favor to cell recruitment, vascularization and osteogenesis as the enrichment of key miRNAs. The animal experiments results showed that CuBG-sEVs stimulated angiogenesis mediated by CD31 and promoted bone regeneration by activating signaling pathways related to osteogenesis. These findings underscored the significant potential of sEVs as alternative strategies to better roles of BG.

Contribution of macrophage polarization in bone metabolism: A literature review

Macrophage polarization divides macrophages into two main cell subpopulations, classically and alternatively activated macrophages (M1 and M2, respectively). M1 polarization promotes osteoclastogenesis, while M2 polarization promotes osteogenesis. The physiological homeostasis of bone metabolism involves a high dynamic balance between osteoclastic-mediated bone resorption and formation. Reportedly, M1/M2 imbalance causes the onset and persistence of inflammation-related bone diseases. Therefore, understanding the research advances in functions and roles of macrophages in such diseases will provide substantial guidance for improved treatment of bone diseases. In this review, we underscore and summarize the research advances in macrophage polarization, and bone-related diseases, such as rheumatoid arthritis, osteoarthritis, and osteoporosis, over the last 5 years. Our findings showed that targeting macrophages and balancing macrophage polarization can effectively reduce inflammation and decrease bone destruction while promoting bone formation and vascular repair. These results indicate that regulating macrophage and macrophage polarization to restore homeostasis is a prospective approach for curing bone-related diseases.

Silica Nanoparticles Decorated with Ceria Quantum Dots Modulate Intra- and Extracellular Reactive Oxygen Species Formation and Selectively Reduce Human A375 Melanoma Cell Proliferation

Nanomaterials show great promise for cancer treatment. Nonetheless, most nanomaterials lack selectivity for cancer cells, damaging healthy ones. Cerium dioxide (ceria, CeO2) nanoparticles have been shown to exert selective toxicity toward cancer cells due to the redox modulating properties they display as their size decreases. However, these particles suffer from poor suspension stability. The efficacy of CeO2 nanoparticles for cancer treatment is hampered by their innate high surface energy, which leads to particle agglomeration and, consequently, reactivity loss. This effect increases as particle size decreases; as such, quantum dots (QDs) suffer most from this phenomenon. In this study, it is proposed that silicon dioxide (silica, SiO2) nanoparticles can provide an inert platform for surface encrusted CeO2 QDs and that the resulting nanocomposite (hereafter QDCeO2/SiO2) not only will exhibit negligible agglomeration compared with CeO2 alone but also will improve the modulation of reactive oxygen species (ROS) leading to selective reduction of human A375 melanoma cell proliferation. The SiO2 nanoparticles had a bimodal size distribution with median particle size of 66 and 168 nm, while the CeO2 quantum dots encrusted on their surface had a size of 3.2 nm. An elevated Ce3+/Ce4+ ratio led to the QDCeO2/SiO2 nanocomposite displaying synergistic superoxide dismutase- and catalase-like activity, favoring the accumulation of ROS at pH 6.5 which translated into QDCeO2/SiO2 exerting selective oxidative stress in, and toward, the melanoma cells. Treatment with 50 μg mL-1 QDCeO2/SiO2 significantly reduced cell proliferation by 27% compared to untreated control cells in the colony formation assay. Treatment with either SiO2 or CeO2 alone did not affect the cell proliferation. These results highlight the benefit of dispersing CeO2 QDs on the surface of core nanoparticles and the resulting enhancement of selective redox reactivity and proliferation arrest when compared to CeO2 nanoparticles alone. Furthermore, the method employed here to encrust CeO2 QDs could lead to the facile synthesis of new nanocomposites with enhanced control of ROS activity, not only for in vitro studies using other cancer cell lines of interest but also in animal models and perhaps leading to clinical trials in melanoma patients.

Au/Ag@ZnS yolk-shell photocatalysts enhanced with noble metals and hyaluronic acid for efficient hydrogen production in rheumatoid arthritis therapy

Rheumatoid arthritis, characterized by the abnormal proliferation of synovial cells and extensive macrophage infiltration, is a chronic inflammatory disease. Molecular hydrogen, known for its antioxidant properties, has shown promise in eliminating reactive oxygen species. However, the low solubility and bioavailability of hydrogen limit the effectiveness of this therapy. To overcome these issues, we developed a novel yolk-shell heterostructure, H-AAZS (Au/Ag@ZnS modified hyaluronic acid), utilizing a hydrothermal cation exchange process. Through ion doping, semiconductor hybridization, and Schottky barriers in H-AAZS, photocatalysis for hydrogen generation has been successfully implemented using 660 nm laser irradiation. Additionally, the H-AAZS demonstrate the capacity for mild photothermal therapy, inducing apoptosis in synovial cells with Au's hot electrons with 660 nm laser irradiation. This strategy not only improves the abnormal proliferation of synovial cells but also avoids the exacerbation of inflammation caused by thermal stimulation. Both in vitro and in vivo experiments validate the synergistic effects of hydrogen production mediated anti-inflammatory responses, macrophage polarization and photothermal therapy. Therefore, this work represents a significant advancement as it ingeniously harnesses photocatalysis to modulate the synovial microenvironment while mitigating the side effects associated with photothermal therapy. This nanocrystal provides new and valuable insights into the potential treatment of Rheumatoid arthritis.

Oxidative stress modulating nanomaterials and their biochemical roles in nanomedicine

Many pathological conditions are predominantly associated with oxidative stress, arising from reactive oxygen species (ROS); therefore, the modulation of redox activities has been a key strategy to restore normal tissue functions. Current approaches involve establishing a favorable cellular redox environment through the administration of therapeutic drugs and redox-active nanomaterials (RANs). In particular, RANs not only provide a stable and reliable means of therapeutic delivery but also possess the capacity to finely tune various interconnected components, including radicals, enzymes, proteins, transcription factors, and metabolites. Here, we discuss the roles that engineered RANs play in a spectrum of pathological conditions, such as cancer, neurodegenerative diseases, infections, and inflammation. We visualize the dual functions of RANs as both generator and scavenger of ROS, emphasizing their profound impact on diverse cellular functions. The focus of this review is solely on inorganic redox-active nanomaterials (inorganic RANs). Additionally, we deliberate on the challenges associated with current RANs-based approaches and propose potential research directions for their future clinical translation.

Carbon dots-supported Zn single atom nanozymes for the catalytic therapy of diabetic wounds

Diabetic wound treatment continues to be a significant clinical issue due to higher levels of oxidative stress, susceptibility to bacterial infections, and chronic inflammatory responses during healing. We rationally developed and synthesized an ultra-small carbon dots (C-dots) loaded with zinc single-atom nanozyme (Zn/C-dots) with the aim of promoting wounds healing by nanocatalytic treatment, especially targeting its complex pathological microenvironment. Zinc single atoms and C-dots form a dual catalytic system with higher enzymatic activity. Furthermore, the Zn/C-dots nanozyme effectively enters cells, accumulates at mitochondria, and removes excess ROS, protecting cells from oxidative stress damage and limiting the release of pro-inflammatory cytokines, hence reducing inflammation. Zinc can synergistically increase the antibacterial action of C-dots (the effective antibacterial rate of 100 µg/mL Zn/C-dots was above 90 %). Unlike traditional C-dots, Zn/C-dots can cause endothelial cell migration and the formation of new blood vessels. In vitro cytotoxicity, blood compatibility, and in vivo toxicity studies of Zn/C-dots show that they are biocompatible. We subsequently utilized the Zn/C-dots nanozymes to treat diabetic rats' chronic wounds for external use, combining them with ROS-responsive hydrogels to create an antioxidative system (H-Zn/C-dots). The hydrogels anchored the Zn/C-dots nanozymes to the wound, allowing for long-term treatment. The results revealed that H-Zn/C-dots can considerably reduce inflammation, accelerate angiogenesis, collagen deposition, and promote tissue remodeling at the diabetic wound site. After 14 days, the wound area had decreased to approximately 9.19 %, making it a potential treatment. STATEMENT OF SIGNIFICANCE: An ultra-small carbon dot with a zinc single-atom nanozyme was designed and manufactured. Zn/C-dots possess antibacterial, ROS-scavenging, and angiogenesis activities. In vivo, the multifunctional ROS-responsive hydrogel incorporating Zn/C-dots could speed up diabetic wound healing.

Orally Deliverable Iron-Ceria Nanotablets for Treatment of Inflammatory Bowel Disease

Ceria-based nanoparticles are versatile in treating various inflammatory diseases, but their feasibility in clinical translation is undermined by safety concerns and a limited delivery system. Meanwhile, the idiopathic nature of inflammatory bowel disease (IBD) calls for a wider variety of therapeutics via moderation of the intestinal immune system. In this regard, the synthesis and oral formulation of iron-ceria nanoparticles (CF NPs) with enhanced nanozymic activity and lower toxicity risk than conventional ceria-based nanoparticles are reported. CF NPs are clustered in calcium phosphate (CaP) and coated with a pH-responsive polymer to provide the enteric formulation of iron-ceria nanotablets (CFNT). CFNT exhibits a marked alleviative efficacy in the dextran sodium sulfate (DSS)-induced enterocolitis model in vivo by modulating the pro-inflammatory behavior of innate immune cells including macrophages and neutrophils, promoting anti-inflammatory cytokine profiles, and downregulating key transcription factors of inflammatory pathways.

Injectable Thermosensitive Gel CH-BPNs-NBP for Effective Periodontitis Treatment through ROS-Scavenging and Jaw Vascular Unit Protection

Periodontitis, a prevalent inflammatory condition in the oral cavity, is closely associated with oxidative stress-induced tissue damage mediated by excessive reactive oxygen species (ROS) production. The jaw vascular unit (JVU), encompassing both vascular and lymphatic vessels, plays a crucial role in maintaining tissue fluid homeostasis and contributes to the pathological process in inflammatory diseases of the jaw. This study presents a novel approach for treating periodontitis through the development of an injectable thermosensitive gel (CH-BPNs-NBP). The gel formulation incorporates black phosphorus nanosheets (BPNs), which are notable for their ROS-scavenging properties, and dl-3-n-butylphthalide (NBP), a vasodilator that promotes lymphatic vessel function within the JVU. These results demonstrate that the designed thermosensitive gel serve as a controlled release system, delivering BPNs and NBP to the site of inflammation. CH-BPNs-NBP not only protects macrophages and human lymphatic endothelial cells from ROS attack but also promotes M2 polarization and lymphatic function. In in vivo studies, this work observes a significant reduction in inflammation and tissue damage, accompanied by a notable promotion of alveolar bone regeneration. This research introduces a promising therapeutic strategy for periodontitis, leveraging the unique properties of BPNs and NBP within an injectable thermosensitive gel.

Cascaded Nanozyme Based pH-Responsive Oxygenation for Targeted Eradication of Resistant Helicobacter Pylori

Nanozymes, as substitutes for natural enzymes, are constructed as cascade catalysis systems for biomedical applications due to their inherent catalytic properties, high stability, tunable physicochemical properties, and environmental responsiveness. Herein, a multifunctional nanozyme is reported to initiate cascade enzymatic reactions specific in acidic environments for resistant Helicobacter pylori (H. pylori) targeting eradication. The cobalt-coated Prussian blue analog based FPB-Co-Ch NPs displays oxidase-, superoxide dismutase-, peroxidase-, and catalase- mimicking activities that trigger •O 2 - ${\mathrm{O}}_2^ - {\bm{\ }}$ and H2O2 to supply O2, thereby killing H. pylori in the stomach. To this end, chitosan is modified on the surface to exert bacterial targeted adhesion and improve the biocompatibility of the composite. In the intestinal environment, the cascade enzymatic activities are significantly inhibited, ensuring the biosafety of the treatment. In vitro, sensitive and resistant strains of H. pylori are cultured and the antibacterial activity is evaluated. In vivo, murine infection models are developed and its success is confirmed by gastric mucosal reculturing, Gram staining, H&E staining, and Giemsa staining. Additionally, the antibacterial capacity, anti-inflammation, repair effects, and biosafety of FPB-Co-Ch NPs are comprehensively investigated. This strategy renders a drug-free approach that specifically targets and kills H. pylori, restoring the damaged gastric mucosa while relieving inflammation.

Temperature-Activated Near-Infrared-II Fluorescence and SERS Dynamic-Reversible Probes for Long-Term Assessment of Osteoarthritis In Vivo

The abnormal fluctuation of temperature in vivo usually reflects the progression of inflammatory diseases. Noninvasive, real-time, and accurate monitoring and imaging of temperature variation in vivo is advantageous for guiding the early diagnosis and treatment of disease, but it remains difficult to achieve. Herein, we developed a temperature-activated near-infrared-II fluorescence (NIR-II FL) and surface-enhanced Raman scattering (SERS) nanoprobe for long-term monitoring of temperature changes in rat arthritis and timely assessment of the status of osteoarthritis. The thermosensitive polymer bearing NIR-II FL dye was grafted onto the surface of nanoporous core-satellite gold nanostructures to form the nanoprobe, wherein the nanoprobe contains NIR-II FL and Raman reference signals that are independent of temperature change. The ratiometric FL1150/FL1550 and S1528/S2226 values of the nanoprobe exhibited a reversible conversion with temperature changes. The nanoprobe accurately distinguishes the temperature variations in the inflamed joint versus the normal joint in vivo by ratiometric FL and SERS imaging, allowing for an accurate diagnosis of inflammation. Meanwhile, it can continuously monitor fluctuations in temperature over an extended period during the onset and treatment of inflammation. The tested temperature change trend could be used as an indicator for early diagnosis of inflammation and real-time evaluation of therapeutic effects.

Neutrophil membrane-derived nanoparticles protect traumatic brain injury via inhibiting calcium overload and scavenging ROS

The secondary injury is more serious after traumatic brain injury (TBI) compared with primary injury. Release of excessive reactive oxygen species (ROS) and Ca2+ influx at the damaged site trigger the secondary injury. Herein, a neutrophil-like cell membrane-functionalized nanoparticle was developed to prevent ROS-associated secondary injury. NCM@MP was composed of three parts: (1) Differentiated neutrophil-like cell membrane (NCM) was synthesized, with inflammation-responsive ability to achieve effective targeting and to increase the retention time of Mn3O4 and nimodipine (MP) in deep injury brain tissue via C-X-C chemokine receptor type 4, integrin beta 1 and macrophage antigen-1. (2) Nimodipine was used to inhibit Ca2+ influx, eliminating the ROS at source. (3) Mn3O4 further eradicated the existing ROS. In addition, NCM@MP also exhibited desirable properties for T1 enhanced imaging and low toxicity which may serve as promising multifunctional nanoplatforms for precise therapies. In our study, NCM@MP obviously alleviated oxidative stress response, reduced neuroinflammation, protected blood-brain barrier integrity, relieved brain edema, promoted the regeneration of neurons, and improved the cognition of TBI mice. This study provides a promising TBI management to relieve the secondary spread of damage.

NIR-II-Responsive Versatile Nanozyme Based on H2O2 Cycling and Disrupting Cellular Redox Homeostasis for Enhanced Synergistic Cancer Therapy

Disturbing cellular redox homeostasis within malignant cells, particularly improving reactive oxygen species (ROS), is one of the effective strategies for cancer therapy. The ROS generation based on nanozymes presents a promising strategy for cancer treatment. However, the therapeutic efficacy is limited due to the insufficient catalytic activity of nanozymes or their high dependence on hydrogen peroxide (H2O2) or oxygen. Herein, we reported a nanozyme (CSA) based on well-defined CuSe hollow nanocubes (CS) uniformly covered with Ag nanoparticles (AgNPs) to disturb cellular redox homeostasis and catalyze a cascade of intracellular biochemical reactions to produce ROS for the synergistic therapy of breast cancer. In this system, CSA could interact with the thioredoxin reductase (TrxR) and deplete the tumor microenvironment-activated glutathione (GSH), disrupting the cellular antioxidant defense system and augmenting ROS generation. Besides, CSA possessed high peroxidase-mimicking activity toward H2O2, leading to the generation of various ROS including hydroxyl radical (•OH), superoxide radicals (•O2-), and singlet oxygen (1O2), facilitated by the Cu(II)/Cu(I) redox and H2O2 cycling, and plentiful catalytically active metal sites. Additionally, due to the absorption and charge separation performance of AgNPs, the CSA exhibited excellent photothermal performance in the second near-infrared (NIR-II, 1064 nm) region and enhanced the photocatalytic ROS level in cancer cells. Owing to the inhibition of TrxR activity, GSH depletion, high peroxidase-mimicking activity of CSA, and abundant ROS generation, CSA displays remarkable and specific inhibition of tumor growth.

Bibliometric and visualization analysis of the application of inorganic nanomaterials to autoimmune diseases

Objective: To conduct bibliometric analysis of the application of inorganic nanomaterials to autoimmune diseases to characterize current research trends and to visualize past and emerging trends in this field in the past 15 years. Methods: The evolution and thematic trends of the application of inorganic nanomaterials to autoimmune diseases from January 1, 1985, to March 15, 2024, were analyzed by bibliometric analysis of data retrieved and extracted from the Web of Science Core Collection (WoSCC) database. A total of 734 relevant reports in the literature were evaluated according to specific characteristics such as year of publication, journal, institution, country/region, references, and keywords. VOSviewer was used to build co-authorship analysis, co-occurrence analysis, co-citation analysis, and network visualization. Some important subtopics identified by bibliometric characterization are further discussed and reviewed. Result: From 2009 to 2024, annual publications worldwide increased from 11 to 95, an increase of 764%. ACS Nano published the most papers (14) with the most citations (1372). China (230 papers, 4922 citations) and the Chinese Academy of Sciences (36 papers, 718 citations) are the most productive and influential country and institution, respectively. The first 100 keywords were co-clustered to form four clusters: (1) the application of inorganic nanomaterials in drug delivery, (2) the application of inorganic nano-biosensing to autoimmune diseases, (3) the use of inorganic nanomaterials for imaging applied to autoimmune diseases, and (4) the application of inorganic nanomaterials in the treatment of autoimmune diseases. Combination therapy, microvesicles, photothermal therapy (PTT), targeting, diagnostics, transdermal, microneedling, silver nanoparticles, psoriasis, and inflammatory cytokines are the latest high-frequency keywords, marking the emerging frontier of inorganic nanomaterials in the field of autoimmune diseases. Sub-topics were further discussed to help researchers determine the scope of research topics and plan research directions. Conclusion: Over the past 39 years, the application of inorganic nanotechnology to the field of autoimmune diseases shows extensive cooperation between countries and institutions, showing a continuous increase in the number of reports in the literature, and has clinical translation prospects. Future research should further improve the safety of inorganic nanomaterials, clarify the mechanism of action of nanomaterials, establish a standardized nanomaterial preparation and performance evaluation system, and ultimately achieve the goal of early detection and precise treatment of autoimmune diseases.

Reprogramming the myocardial infarction microenvironment with melanin-based composite nanomedicines in mice

Myocardial infarction (MI) has a 5-year mortality rate of more than 50% due to the lack of effective treatments. Interactions between cardiomyocytes and the MI microenvironment (MIM) can determine the progression and fate of infarcted myocardial tissue. Here, a specially designed Melanin-based composite nanomedicines (MCN) is developed to effectively treat MI by reprogramming the MIM. MCN is a nanocomposite composed of polydopamine (P), Prussian blue (PB) and cerium oxide (CexOy) with a Mayuan-like structure, which reprogramming the MIM by the efficient conversion of detrimental substances (H+, reactive oxygen species, and hypoxia) into beneficial status (O2 and H2O). In coronary artery ligation and ischemia reperfusion models of male mice, intravenously injecting MCN specifically targets the damaged area, resulting in restoration of cardiac function. With its promising therapeutic effects, MCN constitutes a new agent for MI treatment and demonstrates potential for clinical application.

Emerging nanozyme therapy incorporated into dental materials for diverse oral pathologies

OBJECTIVE

Nanozyme materials combine the advantages of natural enzymes and artificial catalysis, and have been widely applied in new technologies for dental materials and oral disease treatment. Based on the role of reactive oxygen species (ROS) and oxidative stress pathways in the occurrence and therapy of oral diseases, a comprehensive review was conducted on the methods and mechanisms of nanozymes and their dental materials in treating different oral diseases.

METHODS

This review is based on literature surveys from PubMed and Web of Science databases, as well as reviews of relevant researches and publications on nanozymes in the therapy of oral diseases and oral tumors in international peer-reviewed journals.

RESULTS

Given the unique function of nanozymes in the generation and elimination of ROS, they play an important role in the occurrence, development, and treatment of different oral diseases. The application of nanozymes in dental materials and oral disease treatment was introduced, including the latest advances in their use for dental caries, pulpitis, jaw osteomyelitis, periodontitis, oral mucosal diseases, temporomandibular joint disorders, and oral tumors. Future approaches were also summarized and proposed based on the characteristics of these diseases.

SIGNIFICANCE

This review will guide biomedical researchers and oral clinicians to understand the mechanisms and applications of nanozymes in the therapy of oral diseases, promoting further development in the field of dental materials within the oral medication. It is anticipated that more suitable therapeutic agents or dental materials encapsulating nanozymes, specifically designed for the oral environment and simpler for clinical utilization, will emerge in the forthcoming future.

Gas Therapy: Generating, Delivery, and Biomedical Applications

Oxygen (O2), nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H2S), and hydrogen (H2) with direct effects, and carbon dioxide (CO2) with complementary effects on the condition of various diseases are known as therapeutic gases. The targeted delivery and in situ generation of these therapeutic gases with controllable release at the site of disease has attracted attention to avoid the risk of gas poisoning and improve their performance in treating various diseases such as cancer therapy, cardiovascular therapy, bone tissue engineering, and wound healing. Stimuli-responsive gas-generating sources and delivery systems based on biomaterials that enable on-demand and controllable release are promising approaches for precise gas therapy. This work highlights current advances in the design and development of new approaches and systems to generate and deliver therapeutic gases at the site of disease with on-demand release behavior. The performance of the delivered gases in various biomedical applications is then discussed.

Photoacoustic Imaging-Guided Self-Adaptive Hyperthermia Supramolecular Cascade Nano-Reactor for Diabetic Periodontal Bone Regeneration

Commencing with the breakdown of the diabetic osteoimmune microenvironment, multiple pathogenic factors, including hyperglycemia, inflammation, hypoxia, and deleterious cytokines, are conjointly involved in the progression of diabetic periodontal bone regeneration. Based on the challenge of periodontal bone regeneration treatment and the absence of real-time feedback of blood oxygen fluctuation in diabetes mellitus, a novel self-adaptive hyperthermia supramolecular cascade nano-reactor ACFDG is constructed via one-step supramolecular self-assembly strategy to address multiple factors in diabetic periodontal bone regeneration. Hyperthermia supramolecular ACFDG possesses high photothermal conversion efficiency (32.1%), and it can effectively inhibit the vicious cycle of ROS-inflammatory cascade through catalytic cascade reactions, up-regulate the expression of heat shock proteins (HSPs) under near-infrared (NIR) irradiation, which promotes periodontal bone regeneration. Remarkably, ACFDG can provide real-time non-invasive diagnosis of blood oxygen changes during periodontal bone regeneration through photoacoustic (PA) imaging, thus can timely monitor periodontal hypoxia status. In conclusion, this multifunctional supramolecular nano-reactor combined with PA imaging for real-time efficacy monitoring provides important insights into the biological mechanisms of diabetic periodontal bone regeneration and potential clinical theranostics.

PH-sensitive BSA-modified resveratrol micelles targeting macrophages alleviate symptoms of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease, leading to severe inflammatory infiltration and joint damage, accompanied by a decrease in pH of joint microenvironment. Macrophages play an important role in the pathogenesis of RA, with high expression of bovine serum albumin (BSA) receptors on the surface of macrophages. Resveratrol (Res) has strong anti-inflammatory effects, but its application is limited due to its poor water solubility and low bioavailability. Therefore, we constructed pH-sensitive micelles by encapsulating Res and modifying BSA on the surface of the micelles (BSA-Res@Ms), thereby greatly improving the therapeutic effect of RA. Our research results indicated that BSA-Res@Ms had a smooth and uniform appearance, small particle size, high drug encapsulation efficiency, good stability, and pH-sensitive properties. In vitro, BSA-Res@Ms increased the uptake of Res by RAW264.7 cells, reduced the levels of pro-inflammatory cytokines and cleared excess ROS produced by activated RAW264.7 cells, and inhibited the generation of osteoclasts. In vivo, BSA-Res@Ms could target inflamed joint sites, significantly alleviate joint inflammation symptoms, inhibit activated macrophages, improve synovial hyperplasia and inflammatory cell infiltration, and protect cartilage. BSA-Res@Ms provide a very promising method for the treatment of RA, which can effectively improve the inflammatory manifestations of RA.

[ZIF-8@Pt Nanozyme Used for Scavenging Reactive Oxygen Species in the Treatment of Rheumatoid Arthritis]

Objective

To formulate a ZIF-8 nano mimetic enzyme conjugated with platinum metal (ZIF-8@Pt) that can scavenge reactive oxygen species (ROS) and to explore its potential applications in the treatment of rheumatoid arthritis (RA).

Methods

The ZIF-8@Pt nanozyme was created by in situ reduction. Characterization of the nanozyme was then performed and its ability to mimic enzymes was investigated. Cell experiments were conducted using RAW264.7 cells, which were divided into three groups, including the untreated group (UT), the positive control group receiving lipopolysaccharide (LPS), which was designated as the LPS group, and the ZIF-8@Pt group receiving ZIF-8@Pt and LPS treatment. The cell experiments were conducted to evaluate the anti-inflammatory properties of ZIF-8@Pt through scavenging intracellular ROS. On the other hand, a collagen-induced arthritis (CIA) model was induced in rats. Similar to the group designations in the cell experiments, the rats were assigned to three groups, including a healthy control group (the UT group), a positive control group receiving a local injection of PBS solution in the knee joint, which was referred to as the control group, and a treatment group receiving a local injection of ZIF-8@Pt solution in the knee joint, which was referred to as the ZIF-8@Pt group. General evaluation, imaging observation, assessment of inflammatory factors, and pathological evaluation were performed to assess the therapeutic efficacy of ZIF-8@Pt against RA.

Results

The in vitro experiment revealed significant difference in the levels of intracellular ROS and LPS-induced M1-type macrophage polarization between the LPS group and the ZIF-8@Pt group (P<0.05). The in vivo experiment showed that significant difference in the levels of inflammatory factors, including interleukin-1β (IL-1β), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and arginase-1 (Arg-1) in the knee joints of the CIA rats between the LPS group and the ZIF-8@Pt group (P<0.05). Comparing the findings for the ZIF-8@Pt group and the control group, pathology assessment revealed that ZIF-8@Pt reduced local hypoxia and suppressed osteoclastic activity, neovascularization, and M1-type macrophage polarization (P<0.05).

Conclusion

The ZIF-8@Pt enzyme mimetic inhibits macrophage inflammatory polarization by ROS scavenging, thereby improving inflammation in RA. Furthermore, the ZIF-8@Pt nanozyme improves the hypoxic environment and inhibits angiogenesis and bone destruction, demonstrating promising therapeutic efficacy for RA.

Fangji Huangqi Decoction alleviates rheumatoid arthritis through regulating HIF-1α mediated the angiogenesis and the balance between autophagy and apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Fangji Huangqi Decoction (FHD) is frequently prescribed for the clinical treatment of wind-cold and wind-dampness pathogenic superficial deficiency syndrome. It also has a notable curative effect on rheumatoid arthritis (RA).

AIM OF THE STUDY

The study aimed to explore the possible mechanism of FHD against RA and provided a theoretical basis for alternative therapies for RA.

MATERIALS AND METHODS

We used UPLC-Q-TOF-MS to analysis the ingredients and absorbed blood components of FHD. At the same time, the collagen-induced arthritis (CIA) rat model was established to estimate the therapeutic effects on FHD by considering body weight, arthritis score, paw swelling, autonomous movement ability, and synovial microvessel counts. Subsequently, immunofluorescence, immunohistochemistry, and Western blot were employed to detect the anti-angiogenic capacity of FHD in vivo, as well as the levels of apoptosis and autophagy in the synovial tissue. In addition, flow cytometry and Western blot were used to assess the effects of FHD on apoptosis and autophagy in MH7A cells. The effects of FHD on the proliferation and migration of MH7A cells were measured by CCK8 assay, cell migration and, invasion experiments. Finally, a tube formation assay was performed to evaluate the angiogenic capacity of FHD in co-cultures of MH7A cells and HUVEC cells.

RESULTS

Through testing of FHD's original formula, a total of 26 active ingredients have been identified, with 17 of them being absorbed into the bloodstream. FHD significantly improved the pathological symptoms and synovial hyperplasia of CIA rats. FHD could suppress the expression of HIF-1α, promote apoptosis in CIA rat synovial tissue, and suppress autophagy and angiogenesis. In vitro experiments showed that serum containing FHD inhibited the proliferation, migration, and invasion of MH7A cells, and also suppressed the expression of autophagy-related proteins while promoting apoptosis. FHD markedly repressed the expression of HIF-1α protein in TNF-α-stimulated MH7A cells and inhibited the tube formation capacity induced by MH7A cells in HUVEC cells.

CONCLUSIONS

The study had proven that FHD played an excellent anti-RA role, which may be attributed to its potential mechanism of regulating the balance between autophagy and apoptosis in RA FLS by suppressing the HIF-1α, thus contributing to its anti-angiogenic activities.

Harnessing cerium-based biomaterials for the treatment of bone diseases

Bone, an actively metabolic organ, undergoes constant remodeling throughout life. Disturbances in the bone microenvironment can be responsible for pathologically bone diseases such as periodontitis, osteoarthritis, rheumatoid arthritis and osteoporosis. Conventional bone tissue biomaterials are not adequately adapted to complex bone microenvironment. Therefore, there is an urgent clinical need to find an effective strategy to improve the status quo. In recent years, nanotechnology has caused a revolution in biomedicine. Cerium(III, IV) oxide, as an important member of metal oxide nanomaterials, has dual redox properties through reversible binding with oxygen atoms, which continuously cycle between Ce(III) and Ce(IV). Due to its special physicochemical properties, cerium(III, IV) oxide has received widespread attention as a versatile nanomaterial, especially in bone diseases. This review describes the characteristics of bone microenvironment. The enzyme-like properties and biosafety of cerium(III, IV) oxide are also emphasized. Meanwhile, we summarizes controllable synthesis of cerium(III, IV) oxide with different nanostructural morphologies. Following resolution of synthetic principles of cerium(III, IV) oxide, a variety of tailored cerium-based biomaterials have been widely developed, including bioactive glasses, scaffolds, nanomembranes, coatings, and nanocomposites. Furthermore, we highlight the latest advances in cerium-based biomaterials for inflammatory and metabolic bone diseases and bone-related tumors. Tailored cerium-based biomaterials have already demonstrated their value in disease prevention, diagnosis (imaging and biosensors) and treatment. Therefore, it is important to assist in bone disease management by clarifying tailored properties of cerium(III, IV) oxide in order to promote the use of cerium-based biomaterials in the future clinical setting. STATEMENT OF SIGNIFICANCE: In this review, we focused on the promising of cerium-based biomaterials for bone diseases. We reviewed the key role of bone microenvironment in bone diseases and the main biological activities of cerium(III, IV) oxide. By setting different synthesis conditions, cerium(III, IV) oxide nanostructures with different morphologies can be controlled. Meanwhile, tailored cerium-based biomaterials can serve as a versatile toolbox (e.g., bioactive glasses, scaffolds, nanofibrous membranes, coatings, and nanocomposites). Then, the latest research advances based on cerium-based biomaterials for the treatment of bone diseases were also highlighted. Most importantly, we analyzed the perspectives and challenges of cerium-based biomaterials. In future perspectives, this insight has given rise to a cascade of cerium-based biomaterial strategies, including disease prevention, diagnosis (imaging and biosensors) and treatment.

Nanomaterial-Based Repurposing of Macrophage Metabolism and Its Applications

Macrophage immunotherapy represents an emerging therapeutic approach aimed at modulating the immune response to alleviate disease symptoms. Nanomaterials (NMs) have been engineered to monitor macrophage metabolism, enabling the evaluation of disease progression and the replication of intricate physiological signal patterns. They achieve this either directly or by delivering regulatory signals, thereby mapping phenotype to effector functions through metabolic repurposing to customize macrophage fate for therapy. However, a comprehensive summary regarding NM-mediated macrophage visualization and coordinated metabolic rewiring to maintain phenotypic equilibrium is currently lacking. This review aims to address this gap by outlining recent advancements in NM-based metabolic immunotherapy. We initially explore the relationship between metabolism, polarization, and disease, before delving into recent NM innovations that visualize macrophage activity to elucidate disease onset and fine-tune its fate through metabolic remodeling for macrophage-centered immunotherapy. Finally, we discuss the prospects and challenges of NM-mediated metabolic immunotherapy, aiming to accelerate clinical translation. We anticipate that this review will serve as a valuable reference for researchers seeking to leverage novel metabolic intervention-matched immunomodulators in macrophages or other fields of immune engineering.

A Reactive Oxygen Species "Sweeper" Based on Hollow Mesopore Cerium Oxide Nanospheres for Targeted and Anti-Inflammatory Management of Osteoarthritis

Osteoarthritis (OA) is a progressive joint disorder characterized by sustained oxidative stress, chronic inflammation, and the degradation of cartilage. Despite extensive research on nanocarrier treatment strategies, the therapeutic efficacy remains limited due to the lack of satisfactory vehicles that can simultaneously exhibit excellent ROS scavenging capabilities and high drug loading capacity for effective nonsurgical management of OA. In this work, we propose an innovative strategy utilizing hollow mesoporous cerium oxide nanospheres coated with membranes derived from apoptotic chondrocytes as a reactive oxygen species "sweeper" for targeted and anti-inflammatory therapy of OA. The developed DEX@HMCeNs@M demonstrates superior drug loading capacity, notable antioxidant properties, favorable biocompatibility, and controlled drug release. By leveraging the camouflage provided by apoptotic chondrocyte membranes, the engineered DEX@HMCeNs@M, which bear natural "eat me" signals, can effectively mimic chondrocyte apoptotic bodies within the joints, thereby enabling targeted delivery of the anti-inflammatory drug DEX and subsequent controlled release triggered by the acidic environment of OA. Both in vitro and in vivo experiments validate the enhanced therapeutic efficacy of our DEX@HMCeNs@M sweeper, which operates through a synergistic mechanism involving scavenging of ROS overproduction, inhibition of inflammation, restoration of mitochondrial damage, and reduction of chondrocyte apoptosis. These findings underscore the potential and efficiency of our developed DEX@HMCeNs@M strategy as an encouraging interventional approach for the progressive treatment of OA.

Administration of ROS-Scavenging Cerium Oxide Nanoparticles Simply Mixed with Autoantigenic Peptides Induce Antigen-Specific Immune Tolerance against Autoimmune Encephalomyelitis

The scavenging ability of cerium oxide nanoparticles (CeNPs) for reactive oxygen species has been intensively studied in the field of catalysis. However, the immunological impact of these particles has not yet been thoroughly investigated, despite intensive research indicating that modulation of the reactive oxygen species could potentially regulate cell fate and adaptive immune responses. In this study, we examined the intrinsic capability of CeNPs to induce tolerogenic dendritic cells via their reactive oxygen species-scavenging effect when the autoantigenic peptides were simply mixed with CeNPs. CeNPs effectively reduced the intracellular reactive oxygen species levels in dendritic cells in vitro, leading to the suppression of costimulatory molecules as well as NLRP3 inflammasome activation, even in the presence of pro-inflammatory stimuli. Subcutaneously administrated PEGylated CeNPs were predominantly taken up by antigen-presenting cells in lymph nodes and to suppress cell maturation in vivo. The administration of a mixture of PEGylated CeNPs and myelin oligodendrocyte glycoprotein peptides, a well-identified autoantigen associated with antimyelin autoimmunity, resulted in the generation of antigen-specific Foxp3+ regulatory T cells in mouse spleens. The induced peripheral regulatory T cells actively inhibited the infiltration of autoreactive T cells and antigen-presenting cells into the central nervous system, ultimately protecting animals from experimental autoimmune encephalomyelitis when tested using a mouse model mimicking human multiple sclerosis. Overall, our findings reveal the potential of CeNPs for generating antigen-specific immune tolerance to prevent multiple sclerosis, opening an avenue to restore immune tolerance against specific antigens by simply mixing the well-identified autoantigens with the immunosuppressive CeNPs.

Engineering Efferocytosis-Mimicking Nanovesicles to Regulate Joint Anti-Inflammation and Peripheral Immunosuppression for Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic inflammation of the synovial joints and the dysfunction of regulatory T cells (Tregs) in the peripheral blood. Therefore, an optimal treatment strategy should aim to eliminate the inflammatory response in the joints and simultaneously restore the immune tolerance of Tregs in peripheral blood. Accordingly, we developed an efferocytosis-mimicking nanovesicle that contains three functional factors for immunomodulating of efferocytosis, including "find me" and "eat me" signals for professional (macrophage) or non-professional phagocytes (T lymphocyte), and "apoptotic metabolite" for metabolite digestion. We showed that efferocytosis-mimicking nanovesicles targeted the inflamed joints and spleen of mice with collagen-induced arthritis, further recruiting and selectively binding to macrophages and T lymphocytes to induce M2 macrophage polarization and Treg differentiation and T helper cell 17 (Th17) recession. Under systemic administration, the efferocytosis-mimicking nanovesicles effectively maintained the pro-inflammatory M1/anti-inflammatory M2 macrophage balance in joints and the Treg/Th17 imbalance in peripheral blood to prevent RA progression. This study demonstrates the potential of efferocytosis-mimicking nanovesicles for RA immunotherapy.

Advances in metal-organic framework-based nanozymes in ROS scavenging medicine

Reactive oxygen species (ROS) play important roles in regulating various physiological functions in the human body, however, excessive ROS can cause serious damage to the human body, considering the various limitations of natural enzymes as scavengers of ROS in the body, the development of better materials for the scavenging of ROS is of great significance to the biomedical field, and nanozymes, as a kind of nanomaterials which can show the activity of natural enzymes. Have a good potential for the development in the area of ROS scavenging. Metal-organic frameworks (MOFs), which are porous crystalline materials with a periodic network structure composed of metal nodes and organic ligands, have been developed with a variety of active nanozymes including catalase-like, superoxide dismutase-like, and glutathione peroxidase-like enzymes due to the adjustability of active sites, structural diversity, excellent biocompatibility, and they have shown a wide range of applications and prospects. In the present review, we first introduce three representative natural enzymes for ROS scavenging in the human body, methods for the detection of relevant enzyme-like activities and mechanisms of enzyme-like clearance are discussed, meanwhile, we systematically summarize the progress of the research on MOF-based nanozymes, including the design strategy, mechanism of action, and medical application, etc. Finally, the current challenges of MOF-based nanozymes are summarized, and the future development direction is anticipated. We hope that this review can contribute to the research of MOF-based nanozymes in the medical field related to the scavenging of ROS.

pH and ROS Dual-Sensitive Nanocarriers for the Targeted Co-Delivery and On-Demand Sequential Release of Tofacitinib and Glucosamine for Synergistic Rheumatoid Arthritis Treatment

Rheumatoid arthritis (RA) progression involves multiple cell types, and sequential drug action on target cells is necessary for RA treatment. Nanocarriers are widely used for RA treatment; however, the targeted delivery and on-demand release of multiple drugs remains challenging. Therefore, in this study, a dual-sensitive polymer is developed using chondroitin sulfate (CS) for the co-delivery of the cartilage repair agent, glucosamine (GlcN), and anti-inflammatory drug, tofacitinib (Tof). In the joint cavity, acidic pH facilitates the cleavage of GlcN from CS polymer to repair the cartilage damage. Subsequently, macrophage uptake via CS-CD44 binding and intracellular reactive oxygen species (ROS) mediate conversion of (methylsulfanyl)propylamine to a hydrophilic segment jointly triggered rapid Tof/GlcN release via micelle disassembly. The combined effects of Tof, GlcN, and ROS depletion promote the M1-to-M2 polarization shift to attenuate inflammation. The synergistic effects of these agents against RA are confirmed in vitro and in vivo. Overall, the dual pH/ROS-sensitive CS nanoplatform simultaneously delivers GlcN and Tof, providing a multifunctional approach for RA treatment with synergistic drug effects.

A dual dynamically cross-linked hydrogel promotes rheumatoid arthritis repair through ROS initiative regulation and microenvironment modulation-independent triptolide release

High oxidative stress and inflammatory cell infiltration are major causes of the persistent bone erosion and difficult tissue regeneration in rheumatoid arthritis (RA). Triptolide (TPL) has become a highly anticipated anti-rheumatic drug due to its excellent immunomodulatory and anti-inflammatory effects. However, the sudden drug accumulation caused by the binding of "stimulus-response" and "drug release" in a general smart delivery system is difficult to meet the shortcoming of extreme toxicity and the demand for long-term administration of TPL. Herein, we developed a dual dynamically cross-linked hydrogel (SPT@TPL), which demonstrated sensitive RA microenvironment regulation and microenvironment modulation-independent TPL release for 30 days. The abundant borate ester/tea polyphenol units in SPT@TPL possessed the capability to respond and regulate high reactive oxygen species (ROS) levels on-demand. Meanwhile, based on its dense dual crosslinked structure as well as the spontaneous healing behavior of numerous intermolecular hydrogen bonds formed after the breakage of borate ester, TPL could remain stable and slowly release under high ROS environments of RA, which dramatically reduced the risk of TPL exerting toxicity while maximized its long-term efficacy. Through the dual effects of ROS regulation and TPL sustained-release, SPT@TPL alleviated oxidative stress and reprogrammed macrophages into M2 phenotype, showing marked inhibition of inflammation and optimal regeneration of articular cartilage in RA rat model. In conclusion, this hydrogel platform with both microenvironment initiative regulation and TPL long-term sustained release provides a potential scheme for rheumatoid arthritis.

Near-infrared light triggered upconversion nanocomposites with multifunction of enhanced antimicrobial photodynamic therapy and gas therapy for inflammation regulation

Antibacterial photodynamic therapy (aPDT) is highly effective in killing bacteria, while the problem of hypoxia and limited light penetration in deep tissue has not been properly solved. In addition, few aPDT works take into account the regulation of inflammation, which is an important regulatory process after antimicrobial therapy and the final purpose of treatment. In this work, to address the above isssues, we have designed a multi-functional composite UCNPs-Ce6-Mn(CO)5Br@Silane (referred to as UCM@Si), which consists of several key components: Up-conversion nanoparticles (UCNPs: NaErF4:Tm3+@NaYF4:Yb3+), Chlorin e6 (Ce6) and Manganese pentacarbonyl bromide (Mn(CO)5Br). When exposed to near-infrared (NIR) light (980 nm), the UCNPs can emit strong red light at 655 nm which further trigger the aPDT of Ce6. The generated reactive oxygen (ROS) subsequently break the metal carbonyl bond of Mn(CO)5Br, leading to the production of carbon monoxide (CO) molecules as well as manganese ions (Mn2+), which further decomposes hydrogen peroxide (H2O2) in the microenvironment to oxygen (O2). Therefore, this simple nanocomposite not only provides substantial self-oxygen replenishment for enhanced aPDT, but also facilitates effective inflammation regulation via CO across a wide range of deep infections. This approach leverages the unique properties of these materials to combat bacterial infections by simultaneously killing bacteria, regulating inflammation, and enhancing the oxygen levels in the affected microenvironment. This O2 and CO gas based aPDT treatment system offers a promising approach to comprehensively address microbial-induced infectious diseases, particularly deep infections, holding the potential clinical applications.

Advances in local drug delivery technologies for improved rheumatoid arthritis therapy

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by an inflammatory microenvironment and cartilage erosion within the joint cavity. Currently, antirheumatic agents yield significant outcomes in RA treatment. However, their systemic administration is limited by inadequate drug retention in lesion areas and non-specific tissue distribution, reducing efficacy and increasing risks such as infection due to systemic immunosuppression. Development in local drug delivery technologies, such as nanostructure-based and scaffold-assisted delivery platforms, facilitate enhanced drug accumulation at the target site, controlled drug release, extended duration of the drug action, reduced both dosage and administration frequency, and ultimately improve therapeutic outcomes with minimized damage to healthy tissues. In this review, we introduced pathogenesis and clinically used therapeutic agents for RA, comprehensively summarized locally administered nanostructure-based and scaffold-assisted drug delivery systems, aiming at improving the therapeutic efficiency of RA by alleviating the inflammatory response, preventing bone erosion and promoting cartilage regeneration. In addition, the challenges and future prospects of local delivery for clinical translation in RA are discussed.

Metal-Phenolic Networks-Reinforced Extracellular Matrix Scaffold for Bone Regeneration via Combining Radical-Scavenging and Photo-Responsive Regulation of Microenvironment

The limited regulation strategies of the regeneration microenvironment significantly hinder bone defect repair effectiveness. One potential solution is using biomaterials capable of releasing bioactive ions and biomolecules. However, most existing biomaterials lack real-time control features, failing to meet high regulation requirements. Herein, a new Strontium (Sr) and epigallocatechin-3-gallate (EGCG) based metal-phenolic network with polydopamine (PMPNs) modification is prepared. This material reinforces a biomimetic scaffold made of extracellular matrix (ECM) and hydroxyapatite nanowires (nHAW). The PMPNs@ECM/nHAW scaffold demonstrates exceptional scavenging of free radicals and reactive oxygen species (ROS), promoting HUVECs cell migration and angiogenesis, inducing stem cell osteogenic differentiation, and displaying high biocompatibility. Additionally, the PMPNs exhibit excellent photothermal properties, further enhancing the scaffold's bioactivities. In vivo studies confirm that PMPNs@ECM/nHAW with near-infrared (NIR) stimulation significantly promotes angiogenesis and osteogenesis, effectively regulating the microenvironment and facilitating bone tissue repair. This research not only provides a biomimetic scaffold for bone regeneration but also introduces a novel strategy for designing advanced biomaterials. The combination of real-time photothermal intervention and long-term chemical intervention, achieved through the release of bioactive molecules/ions, represents a promising direction for future biomaterial development.

Polymerized Network-Based Artificial Peroxisome Reprogramming Macrophages for Photoacoustic Imaging-Guided Treatment of Rheumatoid Arthritis

Artificial peroxisomes (AP) with enzyme-mimetic catalytic activity and recruitment ability have drawn a great deal of attention in fabricating protocell systems for scavenging reactive oxygen species (ROS), modulating the inflammatory microenvironment, and reprogramming macrophages, which is of great potential in treating inflammatory diseases such as rheumatoid arthritis (RA). Herein, a macrophage membrane-cloaked Cu-coordinated polyphthalocyanine-based AP (CuAP) is prepared with a macrocyclic conjugated polymerized network and embedded Cu-single atomic active center, which mimics the catalytic activity and coordination environment of natural superoxide dismutase and catalase, possesses the inflammatory recruitment ability of macrophages, and performs photoacoustic imaging (PAI)-guided treatment. The results of both in vitro cellular and in vivo animal experiments demonstrated that the CuAP under ultrasound and microbubbles could efficiently scavenge excess ROS in cells and tissues, modulate microenvironmental inflammatory cytokines such as interleukin-1β, tumor necrosis factor-α, and arginase-1, and reprogram macrophages by polarization of M1 (proinflammatory phenotype) to M2 (anti-inflammatory phenotype). We believe this study offers a proof of concept for engineering multifaceted AP and a promising approach for a PAI-guided treatment platform for RA.

Precise modulation and use of reactive oxygen species for immunotherapy

Reactive oxygen species (ROS) play an important role in regulating the immune system by affecting pathogens, cancer cells, and immune cells. Recent advances in biomaterials have leveraged this mechanism to precisely modulate ROS levels in target tissues for improving the effectiveness of immunotherapies in infectious diseases, cancer, and autoimmune diseases. Moreover, ROS-responsive biomaterials can trigger the release of immunotherapeutics and provide tunable release kinetics, which can further boost their efficacy. This review will discuss the latest biomaterial-based approaches for both precise modulation of ROS levels and using ROS as a stimulus to control the release kinetics of immunotherapeutics. Finally, we will discuss the existing challenges and potential solutions for clinical translation of ROS-modulating and ROS-responsive approaches for immunotherapy, and provide an outlook for future research.

Janus Nanofibrous Patch with In Situ Grown Superlubricated Skin for Soft Tissue Repair with Inhibited Postoperative Adhesion

The patch with a superlubricated surface shows great potential for the prevention of postoperative adhesion during soft tissue repair. However, the existing patches suffer from the destruction of topography during superlubrication coating and lack of pro-healing capability. Herein, we demonstrate a facile and versatile strategy to develop a Janus nanofibrous patch (J-NFP) with antiadhesion and reactive oxygen species (ROS) scavenging functions. Specifically, sequential electrospinning is performed with initiators and CeO2 nanoparticles (CeNPs) embedded on the different sides, followed by subsurface-initiated atom transfer radical polymerization for grafting zwitterionic polymer brushes, introducing superlubricated skin on the surface of single nanofibers. The poly(sulfobetaine methacrylate) brush-grafted patch retains fibrous topography and shows a coefficient of friction of around 0.12, which is reduced by 77% compared with the pristine fibrous patch. Additionally, a significant reduction in protein, platelet, bacteria, and cell adhesion is observed. More importantly, the CeNPs-embedded patch enables ROS scavenging as well as inhibits pro-inflammatory cytokine secretion and promotes anti-inflammatory cytokine levels. Furthermore, the J-NFP can inhibit tissue adhesion and promote repair of both rat skin wounds and intrauterine injuries. The present strategy for developing the Janus patch exhibits enormous prospects for facilitating soft tissue repair.

ECM-mimetic, NSAIDs loaded thermo-responsive, immunomodulatory hydrogel for rheumatoid arthritis treatment

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease, and it leads to irreversible inflammation in intra-articular joints. Current treatment approaches for RA include non-steroidal anti-inflammatory drugs (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs), corticosteroids, and biological agents. To overcome the drug-associated toxicity of conventional therapy and transdermal tissue barrier, an injectable NSAID-loaded hydrogel system was developed and explored its efficacy.

RESULTS

The surface morphology and porosity of the hydrogels indicate that they mimic the natural ECM, which is greatly beneficial for tissue healing. Further, NSAIDs, i.e., diclofenac sodium, were loaded into the hydrogel, and the in vitro drug release pattern was found to be burst release for 24 h and subsequently sustainable release of 50% drug up to 10 days. The DPPH assay revealed that the hydrogels have good radical scavenging activity. The biocompatibility study carried out by MTT assay proved good biocompatibility and anti-inflammatory activity of the hydrogels was carried out by gene expression study in RAW 264.7 cells, which indicate the downregulation of several key inflammatory genes such as COX-2, TNF-α & 18s.

CONCLUSION

In summary, the proposed ECM-mimetic, thermo-sensitive in situ hydrogels may be utilized for intra-articular inflammation modulation and can be beneficial by reducing the frequency of medication and providing optimum lubrication at intra-articular joints.

Natural biomimetic nano-system for drug delivery in the treatment of rheumatoid arthritis: a literature review of the last 5 years

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized primarily by synovitis, leading to the destruction of articular cartilage and bone and ultimately resulting in joint deformity, loss of function, and a significant impact on patients' quality of life. Currently, a combination of anti-rheumatic drugs, hormonal drugs, and biologics is used to mitigate disease progression. However, conventional drug therapy has limited bioavailability, and long-term use often leads to drug resistance and toxic side effects. Therefore, exploring new therapeutic approaches for RA is of great clinical importance. Nanodrug delivery systems offer promising solutions to overcome the limitations of conventional drugs. Among them, liposomes, the first nanodrug delivery system to be approved for clinical application and still widely studied, demonstrate the ability to enhance therapeutic efficacy with fewer adverse effects through passive or active targeting mechanisms. In this review, we provide a review of the research progress on the targeting mechanisms of various natural biomimetic nano-delivery systems in RA therapy. Additionally, we predict the development trends and application prospects of these systems, offering new directions for precision treatment of RA.

hCeO2@ Cu5.4O nanoparticle alleviates inflammatory responses by regulating the CTSB-NLRP3 signaling pathway

Inflammatory responses, especially chronic inflammation, are closely associated with many systemic diseases. There are many ways to treat and alleviate inflammation, but how to solve this problem at the molecular level has always been a hot topic in research. The use of nanoparticles (NPs) as anti-inflammatory agents is a potential treatment method. We synthesized new hollow cerium oxide nanomaterials (hCeO2 NPs) doped with different concentrations of Cu5.4O NPs [the molar ratio of Cu/(Ce + Cu) was 50%, 67%, and 83%, respectively], characterized their surface morphology and physicochemical properties, and screened the safe concentration of hCeO2@Cu5.4O using the CCK8 method. Macrophages were cultured, and P.g-lipopolysaccharide-stimulated was used as a model of inflammation and co-cultured with hCeO2@Cu5.4O NPs. We then observe the effect of the transcription levels of CTSB, NLRP3, caspase-1, ASC, IL-18, and IL-1β by PCR and detect its effect on the expression level of CTSB protein by Western blot. The levels of IL-18 and IL-1β in the cell supernatant were measured by enzyme-linked immunosorbent assay. Our results indicated that hCeO2@Cu5.4O NPs could reduce the production of reactive oxygen species and inhibit CTSB and NLRP3 to alleviate the damage caused by the inflammatory response to cells. More importantly, hCeO2@Cu5.4O NPs showed stronger anti-inflammatory effects as Cu5.4O NP doping increased. Therefore, the development of the novel nanomaterial hCeO2@Cu5.4O NPs provides a possible new approach for the treatment of inflammatory diseases.

Biomimetic nanoparticles for effective Celastrol delivery to targeted treatment of rheumatoid arthritis through the ROS-NF-κB inflammasome axis

Previous study has indicated that Celastrol (Cel) has various physiological and pharmacological effects, including antibacterial, antioxidant, pro-apoptotic, anticancer and anti-rheumatoid arthritis (RA) effects. However, low water solubility, low oral bioavailability, narrow treatment window, and high incidence of systemic adverse reactions still limit the further clinical application of Cel. Here, aiming at effectively overcome those shortcomings of Cel to boost its beneficial effects for treating RA, we developed the leukosome (LEUKO) coated biomimetic nanoparticles (NPs) for the targeted delivery of Cel to arthritis injury area in RA. LEUKO were synthesized using membrane proteins purified from activated J774 macrophage. LEUKO and Cel-loaded LEUKO (Cel@LEUKO) were characterized using dynamic light scattering and transmission electron microscopy. Our results demonstrated that Cel@LEUKO can inhibit the inflammatory response of lipopolysaccharide (LPS) induced mouse monocyte macrophage leukemia cells (RAW264.7 cells) and human rheumatoid arthritis synovial fibroblasts (MH7A) cells through the inhibition of reactive oxygen species (ROS)-NF-κB pathway. In addition, research has shown that LEUKO effectively targets and transports Cel to the inflammatory site of RA, increased drug concentration in affected areas, reduced systemic toxicity of Cel, and reduced clinical symptoms, inflammatory infiltration, bone erosion, and serum inflammatory factors in collagen-induced arthritis (CIA) rats.

Nanoparticle-Mediated Multiple Modulation of Bone Microenvironment To Tackle Osteoarthritis

Development of nanomedicines that can collaboratively scavenge reactive oxygen species (ROS) and inhibit inflammatory cytokines, along with osteogenesis promotion, is essential for efficient osteoarthritis (OA) treatment. Herein, we report the design of a ROS-responsive nanomedicine formulation based on fibronectin (FN)-coated polymer nanoparticles (NPs) loaded with azabisdimethylphoaphonate-terminated phosphorus dendrimers (G4-TBP). The constructed G4-TBP NPs-FN with a size of 268 nm are stable under physiological conditions, can be specifically taken up by macrophages through the FN-mediated targeting, and can be dissociated in the oxidative inflammatory microenvironment. The G4-TBP NPs-FN loaded with G4-TBP dendrimer having intrinsic anti-inflammatory property and FN having both anti-inflammatory and antioxidative properties display integrated functions of ROS scavenging, hypoxia attenuation, and macrophage M2 polarization, thus protecting macrophages from apoptosis and creating designed bone immune microenvironment for stem cell osteogenic differentiation. These characteristics of the G4-TBP NPs-FN lead to their effective treatment of an OA model in vivo to reduce pathological changes of joints including synovitis inhibition and cartilage matrix degradation and simultaneously promote osteogenic differentiation for bone repair. The developed nanomedicine formulation combining the advantages of both bioactive phosphorus dendrimers and FN to treat OA may be developed for immunomodulatory therapy of different inflammatory diseases.

Systematic review of the osteogenic effect of rare earth nanomaterials and the underlying mechanisms

Rare earth nanomaterials (RE NMs), which are based on rare earth elements, have emerged as remarkable biomaterials for use in bone regeneration. The effects of RE NMs on osteogenesis, such as promoting the osteogenic differentiation of mesenchymal stem cells, have been investigated. However, the contributions of the properties of RE NMs to bone regeneration and their interactions with various cell types during osteogenesis have not been reviewed. Here, we review the crucial roles of the physicochemical and biological properties of RE NMs and focus on their osteogenic mechanisms. RE NMs directly promote the proliferation, adhesion, migration, and osteogenic differentiation of mesenchymal stem cells. They also increase collagen secretion and mineralization to accelerate osteogenesis. Furthermore, RE NMs inhibit osteoclast formation and regulate the immune environment by modulating macrophages and promote angiogenesis by inducing hypoxia in endothelial cells. These effects create a microenvironment that is conducive to bone formation. This review will help researchers overcome current limitations to take full advantage of the osteogenic benefits of RE NMs and will suggest a potential approach for further osteogenesis research.

The Application of Drugs and Nano-Therapies Targeting Immune Cells in Hypoxic Inflammation

Immune cells are pivotal in the dynamic interplay between hypoxia and inflammation. During hypoxic conditions, HIF-1α, a crucial transcription factor, facilitates the adaptation of immune cells to the hypoxic micro-environment. This adaptation includes regulating immune cell metabolism, significantly impacting inflammation development. Strategies for anti-inflammatory and hypoxic relief have been proposed, aiming to disrupt the hypoxia-inflammation nexus. Research extensively focuses on anti-inflammatory agents and materials that target immune cells. These primarily mitigate hypoxic inflammation by encouraging M2-macrophage polarization, restraining neutrophil proliferation and infiltration, and maintaining Treg/TH17 balance. Additionally, oxygen-releasing nano-materials play a significant role. By alleviating hypoxia and clearing reactive oxygen species (ROS), these nano-materials indirectly influence immune cell functions. This paper delves into the response of immune cells under hypoxic conditions and the resultant effects on inflammation. It provides a comprehensive overview of various therapies targeting specific immune cells for anti-inflammatory purposes and explores nano-materials that either carry or generate oxygen to alleviate anoxic micro-environments.