Oral zero-valent-molybdenum nanodots for inflammatory bowel disease therapy

A cerium nanocluster for effective alleviation of inflammatory bowel disease by scavenging RONS and regulating gut microbiome

Inflammatory bowel disease (IBD) is characterized by excessive generation of reactive oxygen species and reactive nitrogen species (RONS) within the pro-inflammatory microenvironment. Conventional treatments often have serious side effects, making IBD management challenging. Here, a new cerium cluster, Ce12, with a formula of [Ce12(μ 3-O)8(μ 3-OH)8(μ 2-OH)6(ADA)18]∙3H2O∙3CH3CN (ADA- = 1-adamantanecarboxylate) was prepared and capped with β-cyclodextrin (β-CD) through self-assembly process involving the adamantane moiety of Ce12 and β-CD, resulting in Ce12@CD nanoparticles (NPs). Ce12@CD NPs, with good stability and biocompatibility, exhibit excellent reactive RONS scavenging activities due to the presence of a fraction of Ce3+ ions, offering potential for treating inflammatory diseases. Treatment significantly alleviated body weight loss, colon length reduction, and pathological injury of colon in mice with dextran sodium sulfate (DSS)-elicited colitis, thereby repairing the intestinal mucosal barrier and reducing inflammation. RNA sequence analysis revealed that the therapeutic effects of Ce12@CD NPs are highly correlated with IL-17 and TNF signaling pathways, thereby reducing inflammatory factors such as IL-1β and TNF-α, and alleviating intestinal inflammation. Additionally, Ce12@CD NPs successfully modulated DSS-induced gut microbiota imbalances. This work highlights the unique catalytic activity of Ce12@CD NPs in removing RONS and mimicking biological enzymes, showcasing their potential therapeutic applications for inflammatory disorders.

Beta-Sitosterol-Conjugated Sinapic Acid-Engineered Nanoliposome: Biomucoadhesive and Enzyme-Responsive Targeted Oral Therapy in Ulcerative Colitis

Developing oral drug delivery systems is promising for ulcerative colitis (UC). However, the key challenges, including formulation degradation under harsh gastric conditions, poor targeting efficiency, and limited colonic residence, lead to poor therapeutic efficacy that still needs to be tackled. Effective treatment requires a safe, efficacious, enzyme- and pH-responsive, biomucoadhesive oral drug delivery system to overcome these challenges. Therefore, we have developed chitosan-armored 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) nanoliposomes amalgamated with synthesized beta-sitosterol-sinapic acid (Be-S) conjugate, further encapsulated with 3,4-methylenedioxy-β-nitrostyrene (MNS) as NLRP3 inhibitor, termed C@MN@DMBe-S, to overcome the limitation of free MNS and sinapic acid. Formulated by the thin-film hydration method and processed through extrusion, these unilamellar liposomes demonstrated structural stability and mucoadhesive properties due to chitosan coating. This configuration protected the nanoliposomes from the gastric acidic environment and allowed retention in the inflamed colon for 48 h. The enzyme-responsive C@MN@DMBe-S nanoliposome releases sinapic acid at the inflamed colonic site via esterase activity, providing sustained and controlled release of MNS. This synergistic action delivers antioxidant and anti-inflammatory effects while influencing the gut microbiota composition by releasing short-chain fatty acids. Moreover, therapeutic investigations revealed that C@MN@DMBe-S exhibited superior efficacy compared with free MNS when administered orally. The formulation effectively downregulated NF-κB, NLRP3, Caspase-1, and IL-1β expression while upregulating MUC5AC expression, indicating enhanced anti-inflammatory and protective effects and thereby promoting mucosal healing. In addition, C@MN@DMBe-S was found to regulate immune cell expression and effectively downregulate neutrophil infiltration. This armor- and enzyme-responsive strategy elucidates the impact of oral nanomedicines on mitigating UC and is demonstrated as an effective treatment.

Orally Administered Functional Polyphenol-Nanozyme-Armored Probiotics for Enhanced Amelioration of Intestinal Inflammation and Microbiota Dysbiosis

Maintaining microbiota balance and enhancing the antioxidant performance of nanozyme-based probiotic systems are crucial for effective inflammatory bowel disease (IBD) therapy. Despite significant advancements, developing a green and safe coating technology that functionalizes probiotics with nanozymes while preserving the activity of both components remains a challenge. To address this, chitosan-modified epigallocatechin gallate (EGCG-CS, EC)is synthesized, leveraging the intrinsic adhesive and coordination properties of polyphenols to capture gold nanozymes (AuNPs), forming ECA complexes that enhance nanozyme activity. When coated onto Escherichia coli Nissle 1917 (EcN), the resulting ECA@EcN system effectively scavenged reactive oxygen species (ROS), improving probiotic viability and promoting colon accumulation. Mechanistically, ECA protected EcN by suppressing the activation of the Flagellar Assembly and Branched-Chain Amino Acid Synthesis pathways, ultimately alleviating inflammation and modulating intestinal microbial communities to relieve IBD symptoms. Given the biocompatibility of its components and the environmentally friendly assembly approach, this polyphenol-nanozyme-armored probiotic system represents a promising platform for IBD treatment.

CO-Releasing Polyoxometalates Nanozyme with Gut Mucosal Immunity and Microbiota Homeostasis Remodeling Effects for Restoring Intestinal Barrier Integrity

Disruption of the intestinal epithelial barrier, driven by imbalances in gut mucosal immunity and microbial homeostasis, is central to the onset and progression of inflammatory bowel disease (IBD). This study introduces a CO-releasing polyoxometalates (POMs) nanozyme (PMC), synthesized by coordinating pentacarbonyl manganese bromide with molybdenum-based POM nanoclusters. PMC demonstrates targeted accumulation at IBD-affected sites, efficient scavenging of reactive oxygen species (ROS), and responsive CO release, resulting in multiple therapeutic effects. Extensive in vitro and in vivo studies have validated the exceptional capacity of PMC to repair intestinal barrier, attributed to their potent antioxidant and anti-inflammatory properties, thereby achieving significant therapeutic efficacy in ulcerative colitis treatment. 16S rRNA sequencing indicated that PMC efficiently remodeled the gut microbiota composition. Single-cell RNA sequencing indicates a reduction in pro-inflammatory M1 macrophages, alongside suppressed ROS and inflammatory signaling pathways. Concurrently, an increase in reparative M2 macrophages and intestinal stem cells is observed, in addition to significant activation of the VEGF signaling pathway in macrophages and the NOTCH pathway in stem cells, underscoring the potential of PMC to restore immune balance and promote tissue repair. This study positions PMC as a promising, multifunctional therapeutic agent for IBD treatment owing to its robust intestinal barrier-restoring capability.

Enzyme-Mimic Activities of RuCo Bimetallic Nanosheets for Inflammatory Bowel Disease Treatment

The presence of abnormal levels of reactive oxygen species (ROS) is a recognized pathological feature of inflammatory bowel disease (IBD). Therefore, the development of orally administered antioxidants with high antioxidative capacity and gastric acid tolerance for the treatment of IBD is of great significance. Here, we present the design and synthesis of a bimetallic ruthenium-cobalt (RuCo) nanosheet for the treatment of IBD. The Ru-Co atoms within the nanosheet structure exhibit significant electron transfer properties owing to their electronegativity feature. Density functional theory calculations indicate that the RuCo nanosheets have higher d-band centers than the corresponding Ru and Co metal monoliths, which increases the catalytic activity. Such RuCo nanosheets exhibit superoxide dismutase and catalase-like cascade enzyme activities and show robust stability in gastric fluid over a 4 h period when exposed to simulated gastric fluid, ensuring desirable retention of antioxidative activity. Cellular and animal studies show that RuCo nanosheets are capable of effectively reducing oxidative stress, preventing inflammatory responses triggered by an abnormal increase in ROS at intestinal sites, and thus protecting cells from inflammatory damages. This research presents a gastric-acid-stabilized antioxidative nanocatalytic platform for the efficient treatment of inflammatory diseases of the digestive system.

Broad-Spectrum ROS/RNS Scavenging Catalase-Loaded Microreactors for Effective Oral Treatment of Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) such as ulcerative colitis (UC) is an autoimmune disease characterized by persistent inflammation along the gastrointestinal tract with excessive generation of reactive oxygen species (ROS)/reactive nitrogen species (RNS) generation. Here, catalase (CAT)-containing microreactor capsules with long-lasting broad-spectrum ROS/RNS-scavenging capability are developed for the treatment of IBD. In this design, CAT is encapsulated in the dense hydrogel network of calcium alginate (ALG) microspheres, which provides long-term protection of CAT activity in protease-rich intestinal environment. Afterward, the polydopamine (PDA) modification on the surface of CAT@ALG microspheres can provide them bioadhesiveness to achieve prolonged retention in the intestinal tract and broad-spectrum scavenging capability against various types of ROS/RNS beyond hydrogen peroxide. Enteric capsules are further used to protect the CAT@ALG-PDA microspheres from gastric fluid for selective release at the intestinal site. The combined action of PDA and CAT in CAT@ALG-PDA microreactors results in the broad-spectrum scavenging of excess ROS/RNS and regulates redox balance in acute UC rat model, showing satisfactory therapeutic effects superior to the mesalazine and adalimumab at clinically relevant doses without obvious side effects. This work highlights that these CAT@ALG-PDA capsules can act as long-acting broad-spectrum ROS/RNS reactors, promising for IBD treatment.

CaGA nanozymes inhibit oxidative stress and protect mitochondrial function in ulcerative colitis therapy

Ulcerative colitis (UC) is a long-term inflammatory bowel disease characterized by intense inflammation of the colorectal mucosa. Overproduction of reactive oxygen species exacerbates the progression of UC, which is linked to mitochondrial impairment and dysbiosis of the intestinal microbiota. CaGA nanozymes have demonstrated efficacy in the treatment of UC. The modulation of M1 and M2 polarization of macrophages by CaGA nanozymes has been demonstrated to be useful in reducing inflammation. Furthermore, CaGA nanozymes regulate the M1 and M2 polarization of macrophages, efficiently decreasing inflammation. The oral delivery of CaGA nanozymes resulted in their enrichment in inflamed areas of the colon and effectively reduced colonic damage in mice with DSS-induced colitis by improving the repair of the intestinal barrier. An investigation of 16S rDNA sequencing revealed that CaGA nanozymes regulate populations of both pathogenic and helpful bacteria and impact the progression of ulcerative colitis by influencing the tricarboxylic acid (TCA) cycle. Thus, CaGA nanozymes may be employed in the management of ulcerative colitis to control the intestinal milieu and improve the preservation of the intestinal barrier by decreasing the invasion of inflammatory cells and restoring mitochondrial activity. STATEMENT OF SIGNIFICANCE: CaGA nanozymes exhibit multifunctional enzymatic activity, effectively eliminating cellular RONS with robust antioxidant capacity. CaGA nanoenzymes promote macrophage M1 to M2 polarization and produce anti-inflammatory effects. CaGA nanozymes increase cell viability by restoring impaired mitochondrial function, reducing reactive oxygen species (ROS) production, and restoring the ability of mitochondria to produce ATP. CaGA nanozymes modulate intestinal flora diversity and composition, potentially influencing inflammatory pathways via aromatic compound metabolism. They participate in cellular energy and biosynthesis, regulating ulcerative colitis (UC)-related intestinal function through the tricarboxylic acid (TCA) and urea cycles. Calcium ions bind to GA nanomedicine and small particles are readily absorbed by inflammatory cells, preventing diarrhea from being rapidly excreted.

Cerium Oxide-Loaded Exosomes Derived From Regulatory T Cells Ameliorate Inflammatory Bowel Disease by Scavenging Reactive Oxygen Species and Modulating the Inflammatory Response

Background

Abnormal immune homeostasis, which leads to the accumulation of reactive oxygen species (ROS) and an inflammatory response, plays a crucial role in accelerating the progression of inflammatory bowel disease (IBD). The lack of targeted therapeutic strategies significantly hampers the efficacy of clinical treatments for IBD. This study presents cerium oxide nanoparticle-loaded regulatory T cell-derived exosomes (exo@nCeO) as innovative anti-inflammatory and antioxidant agents specifically designed to address the effects of immune dysregulation.

Methods

In this work, the morphology and antioxidant properties of nano-cerium oxide were characterized using transmission electron microscopy, as well as hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl radical assays. Tumor necrosis factor-α and dextran sulfate sodium were employed to establish cellular and animal models of IBD. The impact of exo@nCeO on ROS scavenging and anti-inflammatory activity in intestinal epithelial cells was assessed using dihydroethidium and 2,7-dichlorodihydrofluorescein staining, Western blotting, and apoptosis flow cytometry analysis. Hematoxylin and eosin staining, along with immunohistochemistry and immunofluorescence staining, were utilized to evaluate intestinal epithelial inflammation and ROS levels in the IBD mouse model.

Results

The findings demonstrate that exo@nCeO possesses augmented anti-inflammatory properties and ROS scavenging abilities in intestinal epithelial cells. In murine models of IBD, exo@nCeO effectively maintained the integrity of the intestinal epithelial barrier and impeded the progression of IBD.

Conclusion

This study introduces a novel therapeutic approach for IBD and underscores a potential strategy for addressing diseases associated with inflammation and oxidative stress.

Reduction of colitis in mice by chemically programmed supramolecular nanoassemblies of vitamin-lipid conjugates

Inflammatory bowel disease (IBD) is a relapsing disorder characterized by uncontrolled chronic inflammation of the gastrointestinal tract, posing a significant therapeutic challenge owing to the limited efficacy and undesirable side effects of current therapeutic options. A key pathological hallmark of IBD is the excessive production of reactive oxygen species (ROS). Hence, therapeutic strategies aimed at reducing ROS levels are promising for relieving these inflammatory conditions. Vitamin C-a natural nutrient for the human body-is well known for its potent antioxidant effects. However, the clinical development of vitamin C as a therapeutic drug has been hindered by its poor stability, rapid metabolism, and inadequate tissue accumulation. Herein, we report that the bioavailability of vitamin C can be enhanced by chemically reprogramming it with a small panel of long-chain fatty acids that aid in the aqueous self-assembly of the resulting drug conjugates to create self-deliverable nanoassemblies, enhancing their inflammation disease-oriented delivery and cellular uptake. In mice with dextran sulfate sodium-induced colitis, the optimal vitamin C-lipid nanoassemblies preferentially accumulated in inflamed colonic tissues following systemic administration and substantially ameliorated disease severity. We extended this strategy to incorporate the clinically approved glucocorticoid budesonide into the vitamin C nanosystem, facilitating a synergistic combination. In the chronic colitis model, the combination treatment reduced inflammation without compromising global immunity. Mechanistically, the treatment modulated the intestinal inflammatory microenvironment and altered the immune cell landscape, partly through regulation of the gut microbiome. Given its anticipated negligible side effects, this novel nanoassembly platform leveraging small-molecule lipidation may become a promising therapeutic for treating various inflammatory diseases.

Antihistamine drug loratadine at environmentally relevant concentrations promotes conjugative transfer of antibiotic resistance genes: Coeffect of oxidative stress and ion transport

Due to the widespread use of loratadine (LOR) as an antihistamine, it is widely distributed in the environment as an emerging contaminant. However, its impact on the dissemination of antibiotic resistance genes (ARGs) remains unclear. This study investigated the effect of LOR on the conjugative transfer of ARGs and elucidated the potential mechanisms through transcriptome analysis. The results showed that LOR significantly promoted the frequency of conjugative transfer up to 1.5- to 8.6-fold higher compared with the control group. Exposure to LOR increased reactive oxidative species (ROS) and intracellular Ca2+ concentrations, leading to the upregulation of expression of genes related to transmembrane transport and SOS response. Meanwhile, it stimulated the increase of cell membrane permeability. Moreover, LOR exposure could enhance H+ efflux in donor bacteria, resulting in the decrease of intracellular pH and the elevation of transmembrane potential, which could induce the increase of ion transport, thereby promoting plasmid efflux from the cell membrane. Based on this, we inferred that LOR can induce an increase in ROS level and intracellular Ca2+ concentrations, and promoted the efflux of intracellular H+. This, in turn, triggered the intensification of various ion transport processes on the cell membrane, thereby increasing membrane permeability and accelerating plasmid efflux. Ultimately, the coeffect of oxidative stress response and ion transport promoted conjugative transfer. This study demonstrated that LOR significantly promotes plasmid-mediated conjugative transfer of ARGs, providing novel insights into the mechanisms underlying this process.

Machine Learning-Assisted High-Throughput Screening of Nanozymes for Ulcerative Colitis

Ulcerative colitis (UC) is a chronic gastrointestinal inflammatory disorder with rising prevalence. Due to the recurrent and difficult-to-treat nature of UC symptoms, current pharmacological treatments fail to meet patients' expectations. This study presents a machine learning-assisted high-throughput screening strategy to expedite the discovery of efficient nanozymes for UC treatment. Therapeutic requirements, including antioxidant property, acid stability, and zeta potential, are quantified and predicted by using a machine learning model. Non-quantifiable attributes, including intestinal barrier repair efficacy and biosafety, are assessed via high-throughput screening. Feature significance analysis, sure independence screening, and sparsifying operator symbolic regression reveal the high-dimensional structure-activity relationships between material features and therapeutic needs. SrDy2O4 with high stability, low toxicity, targeting ability, and reactive oxygen species (ROS) scavenging capability is identified, which reduces ROS production, lowers cytochrome C levels in cytoplasm, and inhibits apoptosis in intestinal epithelial cells by stabilizing the mitochondrial membrane potential. Mice treated with SrDy2O4 show improvements in colon length and body weight compared with dextran sodium sulfate salt-treated model group. Transcriptomic and 16S rRNA sequencing analyses show that SrDy2O4 boosts beneficial gut bacteria, and decreases pathogenic bacteria, thereby effectively restoring gut microbiota balance. Moreover, SrDy2O4 offers the advantage of X-ray imaging without side effects.

Yeast-Inspired Orally-Administered Nanocomposite Scavenges Oxidative Stress and Restores Gut Immune Homeostasis for Inflammatory Bowel Disease Treatment

Excessive oxidative stress, dysregulated immune homeostasis, and disruption of the intestinal epithelial barrier are crucial features of inflammatory bowel disease (IBD). Traditional treatments focusing solely on inflammation resolution remain unsatisfactory. Herein, a yeast-inspired orally administered nanocomposite was developed. First, the MD@MPDA core was fabricated by integrating manganese dioxide (MnO2) nanozymes onto diallyl trisulfide (H2S prodrug)-loaded mesoporous polydopamine nanoparticles (MPDA). Then, yeast cell wall (YCW) was chosen to encapsulate MD@MPDA, namely, YMD@MPDA. The β-glucan embedded in the YCW shell not only protected the nanocomposite from the harsh gastrointestinal environment but also allowed the targeting enrichment in the inflamed colon. Furthermore, M1 macrophages triggered the intracellular GSH-responsive H2S release in the pathological microenvironment. MD@MPDA effectively alleviated inflammatory responses by MnO2-mediated ROS-scavenging and H2S-participated immunomodulation. The synergistic action contributed to macrophage mitochondrial function restoration and M2 polarization by suppressing NOX4 signaling and p38 MAPK pro-inflammatory signaling. In the mice model of dextran sulfate sodium (DSS)-induced IBD, the multipronged manner of scavenging oxidative stress, remodeling innate and adaptive immune homeostasis, and reshaping gut microbiota caused by YMD@MPDA effectively ameliorated inflammation and restored intestinal barrier functions. Overall, the YMD@MPDA nanocomposite provides a promising codelivery strategy of antioxidative nanozymes and gas prodrugs for the comprehensive management of IBD.

Classification of Nanomaterial Drug Delivery Systems for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, primarily arises from defects in the colonic barrier, imbalances of the gut microbiota, and immune response issues. These complex causes make it difficult to achieve a complete cure. Patients with IBD frequently experience recurrent abdominal pain and bloody diarrhea, while severe cases may result in intestinal obstruction, perforation, and cancer. Lifelong maintenance therapy may thus be needed to manage these symptoms; however, traditional IBD drugs, such as 5-aminosalicylic acid, glucocorticoids, immunosuppressants, and biological agents, are often associated with problems including poor solubility, instability, and ineffective targeting, as well as causing serious side effects in non-target tissues. Nanomaterial drug delivery systems (NDDS) have recently shown great promise in optimizing drug distribution, solubility through biocompatible coatings, enhancing bioavailability via PEGylation and reducing side effects. These formulations can enhance a drug's pharmacokinetics by modifying its properties, improve its ability to cross barriers, and boost bioavailability. In addition, NDDS can enable targeted delivery, increase local drug concentrations, improve efficacy, and reduce side effects, as well as protecting active drug molecules from immune recognition and protease degradation. The clinical use of these systems for treating IBD, however, requires further research. This review summarizes the classification of NDDS for IBD, and concludes that, despite ongoing challenges, NDDS may represent an effective treatment approach for IBD. In summary, NDDS enhance the targeted delivery of therapeutic agents to specific cells or tissues, thereby improving drug bioavailability and therapeutic efficacy. These systems effectively surmount biological barriers, facilitating efficient drug delivery to targeted sites, which is crucial for attaining optimal therapeutic outcomes. This review contributes to a deeper understanding of how the physicochemical properties of NDDS influence pharmacological behavior in vivo and can expedite their clinical translation.

Activation of PPARγ regulates M1/M2 macrophage polarization and attenuates dextran sulfate sodium salt-induced inflammatory bowel disease via the STAT-1/STAT-6 pathway

This study aimed to investigate whether activation of PPARγ regulates M1/M2 macrophage polarization to attenuate dextran sulfate sodium salt (DSS)-induced inflammatory bowel disease (IBD) via the STAT-1/STAT-6 pathway in vivo and in vitro. We first examined the effect of PPARγ on macrophage polarization in LPS/IFN-γ-treated M1 RAW264.7 cells and IL-4/IL-13-treated M2 RAW264.7 cells. Then, 40 male C57BL/6 mice were randomly divided into five groups: the Sham, IBD, IBD + fludarabine (FLU), IBD + IL-4, and IBD + pioglitazone (PI) groups. The mice received 2.5% DSS in their drinking water for 7 days and then received regular water for 2 days to establish the experimental IBD murine model. The mice in the IBD + FLU, IBD + IL-4, and IBD + PI groups were intraperitoneally injected with FLU, IL-4, and PI, respectively, for 9 days. Clinical symptoms, intestinal barrier function, macrophage polarization, PPARγ, and the STAT-1/STAT-6 pathway were analyzed. Activation of PPARγ decreased M1 polarization marker expression and STAT-1 phosphorylation and increased M2 polarization marker expression and STAT-6 phosphorylation in RAW264.7 cells. Activation of PPARγ attenuated disease symptoms, such as weight loss, diarrhea, and bloody stool. Histological analysis revealed that PI treatment reduced inflammatory cell infiltration, restored the mucosal architecture, and improved the expression of tight junction proteins. Moreover, the activation of PPARγ decreased the expression of iNOS and increased the expression of Arg-1, Fizz 1, and Ym 1 by inhibiting STAT-1 phosphorylation and promoting STAT-6 phosphorylation in mice with DSS-induced IBD. Activation of PPARγ regulates M1/M2 macrophage polarization to attenuate DSS-induced IBD via the STAT-1/STAT-6 pathway in vivo and in vitro.

Oral Lactoferrin-Responsive Formulation Anchoring around Inflammatory Bowel Region for IBD Therapy

Oral formulation is the ideal treatment method for inflammatory bowel disease (IBD) therapy, but the mucosal damage and diarrhea symptoms impede the drug retention around the inflammatory region, severely limiting IBD therapeutic efficacy. To address this, an oral astaxanthin (Ast) precise delivery formulation is developed with the selective Ast anchoring around the inflammatory region by the novel lactoferrin (LF)-responsive flocculation. This formulation also heightens the apparent solubility of Ast with the minimized edible safety risks for the edible raw materials. For in vivo IBD therapy, the precise delivery formulation exhibits remarkable outcomes, including a significant increase in colon length and a 100% survival rate. Furthermore, it is verified that the mechanism of treatment is primarily attributed to the improved immunoregulation, epithelial repair, and gut microbiota remodeling after the LF-responsive flocculation. This effective inflammatory-responsive delivery design is instructive and valuable to develop more precise delivery systems for IBD therapy.

Oral Akkermansia muciniphila Biomimetic Nanotherapeutics for Ulcerative Colitis Targeted Treatment by Repairing Intestinal Epithelial Barrier and Restoring Redox Homeostasis

The structural disruption of intestinal barrier and excessive reactive oxygen/nitrogen species (RONS) generation are two intertwined factors that drive the occurrence and development of ulcerative colitis (UC). Synchronously restoring the intestinal barrier and mitigating excess RONS is a promising strategy for UC management, but its treatment outcomes are still hindered by low drug accumulation and retention in colonic lesions. Inspired by intestine colonizing bacterium, we developed a mucoadhesive probiotic Akkermansia muciniphila-mimic entinostat-loaded hollow mesopores prussian blue (HMPB) nanotherapeutic (AM@HMPB@E) for UC-targeted therapy via repairing intestinal barrier and scavenging RONS. After oral administration, the negatively charged AM@HMPB@E specifically bind to the positively charged inflamed colon lesions via electrostatic interactions and Akkermansia muciniphila membrane-mediated bioadhesion mechanism. Subsequently, the superoxide dismutase (SOD)-, and catalase (CAT)-like HMPB eliminated RONS, thereby alleviating RONS-mediated inflammation and intestinal epithelial damage. Meanwhile, the UC-site locally released entinostat could repair the damaged intestinal epithelial barrier by inhibiting intestinal endothelial cell apoptosis and up-regulating the expression of tight junctions. Both in vitro and in vivo results shown that AM@HMPB@E not only exhibited an exceptional retention in the colitis site but also demonstrated superior therapeutic efficacy compared to the first-line drug sulfasalazine, as evidenced by the longer colon, less rectal bleeding and body weight loss. Collectively, our findings highlight the clinical application prospects of this synchronous nanotherapeutic strategy for UC treatment, offering a paradigm for the rational design of oral nanomedicine.

Nanomotors as Therapeutic Agents: Advancing Treatment Strategies for Inflammation-Related Diseases

Inflammation is a physiological response of the body to harmful stimuli such as pathogens, damaged cells, or irritants, involving a series of cellular and molecular events. It is associated with various diseases including neurodegenerative disorders, cancer, and atherosclerosis, and is a leading cause of global mortality. Key inflammatory factors, such as Tumor Necrosis Factor-alpha (TNF-α), Interleukin-1 (IL-1), Interleukin-6 (IL-6), Monocyte Chemoattractant Protein-1 (MCP-1/CCL2), RANTES (CCL5), and prostaglandins, play central roles in inflammation and disease progression. Traditional treatments such as NSAIDs, steroids, biologic agents, and antioxidants have limitations. Recent advancements in nanomaterials present promising solutions for treating inflammation-related diseases. Unlike nanomaterials that rely on passive targeting and face challenges in precise drug delivery, nanomotors, driven by chemical or optical stimuli, offer a more dynamic approach by actively navigating to inflammation sites, thereby enhancing drug delivery efficiency and therapeutic outcomes. Nanomotors allow for controlled drug release in response to specific environmental changes, such as pH and inflammatory factors, ensuring effective drug concentrations at disease sites. This active targeting capability enables the use of smaller drug doses, which reduces overall drug usage, costs, and potential side effects compared to traditional treatments. By improving precision and efficiency, nanomotors address the limitations of conventional therapies and represent a significant advancement in the treatment of inflammation-related diseases. This review summarizes the latest research on nanomotor-mediated treatment of inflammation-related diseases and discusses the challenges and future directions for optimizing their clinical translation.

Gnetupendin A protects against ischemic stroke through activating the PI3K/AKT/mTOR-dependent autophagy pathway

BACKGROUND

Autophagy has been recently emerged as a prominent factor in the pathogenesis of ischemic stroke (IS) and is increasingly being considered as a potential therapeutic target for IS. Gnetum parvifolium has been identified as a potential therapeutic agent for inflammatory diseases such as rheumatism and traumatic injuries. However, the pharmacological effects of Gnetupindin A (GA), a stilbene compound isolated from Gnetum parvifolium, have not been fully elucidated until now.

OBJECTIVE

Here we identified the therapeutic potential of GA for IS, deeply exploring the possible mechanisms related to its regulation of autophagy.

METHODS

The mouse model of middle cerebral artery occlusion-reperfusion (MCAO/R) and the oxygen-glucose deprivation reperfusion (OGD/R)-exposed cells served as models to study the protection of GA against IS. The adeno-associated virus (AAV) encoding shAtg5, in conjunction with autophagy inhibitor 3-Methyladenine (3-MA) were utilized to explore the role of GA in regulating autophagy following IS. Molecular docking, CETSA, and DARTS were used to identify the specific therapeutic target of GA. PI3K inhibitor LY294002 was employed to test the participation of PI3K in GA-mediated autophagy and neuroprotective effects following IS.

RESULTS

Our findings revealed that treatment with GA significantly alleviated the brain infract volume, edema, improved neurological deficits and attenuated apoptosis. Mechanistically, we found that GA promoted autophagic flow both in vivo and in vitro after IS. Notably, neural-targeted knockdown of Atg5 abolished the neuroprotective effects mediated by GA. Inhibition of autophagy using 3-MA blocked the attenuation on apoptosis induced by GA. Moreover, molecular docking, CETSA, and DARTS analysis demonstrated that GA specifically targeted PI3K and further inhibited the activation of PI3K/AKT/mTOR signaling pathway. LY294002, which inhibits PI3K, reversed GA-induced autophagy and neuroprotective effects on OGD/R-treated cells.

CONCLUSION

We demonstrated, for the first time, that GA protects against IS through promoting the PI3K/AKT/mTOR-dependent autophagy pathway. Our findings provide a novel mechanistic insight into the anti-IS effect of GA in regulating autophagy.

Intestinal nanoparticle delivery and cellular response: a review of the bidirectional nanoparticle-cell interplay in mucosa based on physiochemical properties

Orally administered nanocarriers play an important role in improving druggability, promoting intestinal absorption, and enhancing therapeutic applications for the treatment of local and systemic diseases. However, the delivering efficiency and cell response in mucosa to orally administered nanocarriers is affected by the physiological environment and barriers in the gastrointestinal tract, the physicochemical properties of the nanocarriers, and their bidirectional interactions. Goblet cells secrete and form extracellular mucus, which hinders the movement of nanoparticles. Meanwhile, intestinal epithelial cells may absorb the NPs, allowing for their transcytosis or degradation. Conversely, nanoparticle-induced toxicity may occur as a biological response to the nanoparticle exposure. Additionally, immune response and cell functions in secretions such as mucin, peptide, and cytokines may also be altered. In this review, we discuss the bidirectional interactions between nanoparticles and cells focusing on enterocytes and goblet cells, M cells, and immune cells in the mucosa according to the essential role of intestinal epithelial cells and their crosstalk with immune cells. Furthermore, we discuss the recent advances of how the physiochemical properties of nanoparticles influence their interplay, delivery, and fate in intestinal mucosa. Understanding the fate of nanoparticles with different physiochemical properties from the perspective of their interaction with cells in mucosa provides essential support for the development, rational design, potency maximation, and application of advanced oral nanocarrier delivery systems.

Biomedical-Optical-Window Tailored Cyanines for Steerable Inflammatory Bowel Disease Theranostic

Tailored photophysical properties and chemical activity is the ultimate pursuit of functional dyes for in vivo biomedical theranostics. In this work, the independent regulation of the absorption and fluorescence emission wavelengths of heptamethine cyanines is reported. These dyes retain near-infrared fluorescence emission (except a nitro-modified dye) while feature variable absorption wavelengths ranging from 590 to 860 nm. This enables to obtain customized functional dyes that meet the excitation and fluorescence wavelength requirements defined by the optical properties of tissues for in vivo biomedical applications. Typically, a nitro-modified photothermal active derivative Cy-Mu-7-9 is used, which features strong absorption at 810 nm in PBS, a wavelength that balanced the tissue penetration depth and non-specific photothermal effect, to realize non-destructive inflammatory bowel disease (IBD) therapy via photothermal induced up-regulation of heat shock protein 70 in the intestinal epithelial cells. The corresponding amino-modified dye Cy-Mu-7-9-NH2, which can be formed in health enteric cavity by Cy-Mu-7-9 after oral administration, is a fluorescence compound with the emission of 800 nm in PBS. Based on the IBD sensitive transformation of Cy-Mu-7-9 and Cy-Mu-7-9-NH2, in vivo IBD theranostic and therapeutic effect evaluation is realized via the synergy of fluorescence imaging and photothermal therapy for the first time.

Oral Administration of Bioactive Nanoparticulates for Inflammatory Bowel Disease Therapy by Mitigating Oxidative Stress and Restoring Intestinal Microbiota Homeostasis

The management of inflammatory bowel disease (IBD) continues to pose significant challenges due to the absence of curative therapies and a high rate of recurrence. Therefore, it is imperative to explore novel approaches to enhance the efficacy of IBD therapy. Herein, a bioactive nanoparticulate s is tailored designed to achieve a "Pull-Push" approach for efficient and safe IBD treatment by integrating reactive oxygen species (ROS) scavenging (Pull) with anti-inflammatory agent delivery (Push) in the inflammatory microenvironment. The multifunctional nanomedicine, designated MON-PAMAM@SASP, is developed through the encapsulation of sulfasalazine (SASP), a widely utilized clinical drug for the treatment of IBD, within cationic diselenide-bridged mesoporous organosilica nanoparticles (MONs) that possess significant antioxidant properties. Herein, poly(amidoamine) (PAMAM) endows the original MONs with positive charge characteristics. The MON-PAMAM@SASP not only displays the remarkable capability of neutralizing ROS to ameliorates intestinal damage, but also achieves controllable release of SASP to mitigate intestinal inflammation. Consequently, this nanomedicine effectively mitigates IBD by colitis in mouse models, and our current research has not identified any significant drug toxicity. Beyond regulating inflammatory microenvironment in intestine, treatment with MON-PAMAM@SASP results in increased richness and restores intestinal microbiota homeostasis, thereby mitigating IBD to a certain extent. Together, our work provides a highly versatile "Pull-Push" approach for IBD management and encourages the development of similar nanomedicine to treating multiple inflammatory diseases of gastrointestinal tract.

Multifunctional MnGA Nanozymes for the Treatment of Ulcerative Colitis by Reducing Intestinal Inflammation and Regulating the Intestinal Flora

In ulcerative colitis (UC), the formation of an inflammatory environment is due to the combined effects of excess production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), overproduction of proinflammatory cytokines, and disruption of immune system function. There are many kinds of traditional drugs for the clinical treatment of UC, but long-term drug use can cause toxic side effects and drug resistance and can also reduce patient compliance and other drawbacks. Hence, in light of the clinical challenges associated with UC, including the limitations of existing treatments, intense adverse reactions and the development of resistance to medications, no novel therapeutic agents that offer effective relief and maintain a high level of biosafety are urgently needed. Although many anti-inflammatory nanomedicines have been developed by researchers, the development of efficient and nontoxic nanomedicines is still a major challenge in clinical medicine. Using the natural product gallic acid and the metal compound manganese chloride, a highly effective and nontoxic multifunctional nanoenzyme was developed for the treatment of UC. Nanozymes can effectively eliminate ROS and RNS to reduce the inflammation of intestinal epithelial cells caused by oxidation, facilitate the restoration of the intestinal epithelial barrier through the upregulation of tight junction protein expression, and balance the intestinal microbiota to maintain the stability of the intestinal environment. Using a rodent model designed to mimic UC, we monitored body weight, colon length, the spleen index, and the degree of tissue damage and demonstrated that manganese gallate (MnGA) nanoparticles can reduce intestinal inflammation by clearing ROS and active nitrogen. Intestinal flora sequencing revealed that MnGA nanoparticles could regulate the intestinal flora, promote the growth of beneficial bacteria and decrease the levels of detrimental bacteria within the intestinal tract in a mouse model of UC. Thus, MnGA nanoparticles can maintain the balance of the intestinal flora. This study demonstrated that MnGA nanoparticles are excellent antioxidant and effective anti-inflammatory agents, have good biosafety, and can effectively treat UC.

Selenoprotein S maintains intestinal homeostasis in ulcerative colitis by inhibiting necroptosis of colonic epithelial cells through modulation of macrophage polarization

Rationale: Macrophage polarization plays an important role in the inflammatory regulation of ulcerative colitis (UC). In this context, necroptosis is a type of cell death that regulates intestinal inflammation, and selenoprotein S (SelS) is a selenoprotein expressed in intestinal epithelial cells and macrophages that prevents intestinal inflammation. However, the underlying mechanisms of SelS in both cell types in regulating UC inflammatory responses remain unclear. Therefore, the direct effect of SelS deficiency on necroptosis in colonic epithelial cells (CECs) was investigated. In addition, whether SelS knockdown exacerbated intestinal inflammation by modulating macrophage polarization to promote necroptosis in CECs was assessed. Methods: The UC model of SelS knockdown mice was established with 3.5% sodium dextran sulfate, and clinical indicators and colon injury were evaluated in the mice. Moreover, SelS knockdown macrophages and CECs cultured alone/cocultured were treated with IL-1β. The M1/M2 polarization, NF-κB/NLRP3 signaling pathway, oxidative stress, necroptosis, inflammatory cytokine, and tight junction indicators were analyzed. In addition, co-immunoprecipitation, liquid chromatography-mass spectrometry, laser confocal analysis, and molecular docking were performed to identify the interacting proteins of SelS. The GEO database was used to assess the correlation of SelS and its target proteins with macrophage polarization. The intervention effect of four selenium supplements on UC was also explored. Results: Ubiquitin A-52 residue ribosomal protein fusion product 1 (Uba52) was identified as a potential interacting protein of SelS and SelS, Uba52, and yes-associated protein (YAP) was associated with macrophage polarization in the colon tissue of patients with UC. SelS deficiency in CECs directly induced reactive oxygen species (ROS) production, necroptosis, cytokine release, and tight junction disruption. SelS deficiency in macrophages inhibited YAP ubiquitination degradation by targeting Uba52, promoted M1 polarization, and activated the NF-κB/NLRP3 signaling pathway, thereby exacerbating ROS-triggered cascade damage in CECs. Finally, exogenous selenium supplementation could effectively alleviate colon injury in UC. Conclusion: SelS is required for maintaining intestinal homeostasis and that its deletion enhances necroptosis in CECs, which is further exacerbated by promoting M1 macrophage polarization, and triggers more severe barrier dysfunction and inflammatory responses in UC.

Nanorepair medicine for treatment of organ injury

Organ injuries, such as acute kidney injury, ischemic stroke, and spinal cord injury, often result in complications that can be life-threatening or even fatal. Recently, many nanomaterials have emerged as promising agents for repairing various organ injuries. In this review, we present the important developments in the field of nanomaterial-based repair medicine, herein referred to as 'nanorepair medicine'. We first introduce the disease characteristics associated with different types of organ injuries and highlight key examples of relevant nanorepair medicine. We then provide a summary of existing strategies in nanorepair medicine, including organ-targeting methodologies and potential countermeasures against exogenous and endogenous pathologic risk factors. Finally, we offer our perspectives on current challenges and future expectations for the advancement of nanomedicine designed for organ injury repair.

Highly spontaneous spin polarization engineering of single-atom artificial antioxidases towards efficient ROS elimination and tissue regeneration

The creation of atomic catalytic centers has emerged as a conducive path to design efficient nanobiocatalysts to serve as artificial antioxidases (AAOs) that can mimic the function of natural antioxidases to scavenge noxious reactive oxygen species (ROS) for protecting stem cells and promoting tissue regeneration. However, the fundamental mechanisms of diverse single-atom sites for ROS biocatalysis remain ambiguous. Herein, we show that highly spontaneous spin polarization mediates the hitherto unclear origin of H2O2-elimination activities in engineering ferromagnetic element (Fe, Co, Ni)-based AAOs with atomic centers. The experimental and theoretical results reveal that Fe-AAO exhibits the best catalase-like kinetics and turnover number, while Co-AAO shows the highest glutathione peroxidase-like activity and turnover number. Furthermore, our investigations prove that both Fe-AAO and Co-AAO can effectively secure the functions of stem cells in high ROS microenvironments and promote the repair of injured tendon tissue by scavenging H2O2 and other ROS. We believe that the proposed highly spontaneous spin polarization engineering of ferromagnetic element-based AAOs will provide essential guidance and practical opportunities for developing efficient AAOs for eliminating ROS, protecting stem cells, and accelerating tissue regeneration.

Molybdenum Nanoparticles Alleviate MC903-Induced Atopic Dermatitis-Like Symptoms in Mice by Modulating the ROS-Mediated NF-κB and Nrf2 /HO-1 Signaling Pathways

Purpose

Atopic dermatitis (AD) is a chronic inflammatory skin condition that can affect individuals of all ages. Recent research has shown that oxidative stress plays a crucial role in the development of AD. Therefore, inhibiting oxidative stress may be an effective therapeutic approach for AD. Nano-molybdenum is a promising material for use as an antioxidant. We aimed to evaluate the therapeutic effects and preliminary mechanisms of molybdenum nanoparticles (Mo NPs) by using a murine model of chemically induced AD-like disease.

Methods

HaCaT cells, a spontaneously immortalized human keratinocyte cell line, were stimulated by tumor necrosis factor-alpha /interferon-gamma after pre-treatment with Mo NPs. Reactive oxygen species levels, production of inflammatory factors, and activation of the nuclear factor kappa-B and the nuclear factor erythroid 2-related factor pathways were then evaluated. Mo NPs was topically applied to treat a murine model of AD-like disease induced by MC903, a vitamin D3 analog. Dermatitis scores, pruritus scores, transepidermal water loss and body weight were evaluated. AD-related inflammatory factors and chemokines were evaluated. Activation of the nuclear factor kappa-B and nuclear factor erythroid 2-related factor / heme oxygenase-1 pathways was assessed.

Results

Our data showed that the topical application of Mo NPs dispersion could significantly alleviate AD skin lesions and itching and promote skin barrier repair. Further mechanistic experiments revealed that Mo NPs could inhibit the excessive activation of the nuclear factor kappa-B pathway, promote the expression of nuclear factor erythroid 2-related factor and heme oxygenase-1 proteins, and suppress oxidative stress reactions. Additionally, they inhibited the expression of thymic stromal lymphopoietin, inflammatory factors, and chemokines, thereby alleviating skin inflammation.

Conclusion

Mo NPs present a promising alternative treatment option for patients with AD as they could address three pivotal mechanisms in the pathogenesis of AD concurrently.

Tofacitinib Citrate Coordination-Based Dual-Responsive/Scavenge Nanoplatform Toward Regulate Colonic Inflammatory Microenvironment for Relieving Colitis

Ulcerative colitis is an inflammation of the colon characterized by immune dysregulation and intestinal inflammation. Developing safe oral nanomedicines that suppress intestinal inflammation, while modulating colonic inflammatory microenvironment by scavenging reactive oxygen species (ROS) and hydrogen sulfide (H2S) is crucial for the effective treatment of colitis. Here, the tofacitinib citrate and copper coordination-based nanoparticle (TF-Cu nanoparticle, T-C) to dual-scavenge ROS and H2S by coordination competition is synthesized. Moreover, the coordination of T-C using computer simulation is explored. To enhance the acid stability and inflammatory targeting of T-C, it is encapsulated with hyaluronic acid-modified chitosan, along with a calcium pectinate coating (T-C@HP). Owing to the dual pH/pectinase-responsive characteristics of T-C@HP, the nanoplatform can target inflamed colonic lesions, inhibiting phosphorylated Janus kinase 1. Furthermore, T-C@HP scavenges ROS and H2S, as well as increases NADPH levels, which is investigated by combining biosensor (HyPer7 and iNap1/c) and chemical probes. T-C@HP also alleviates colitis by regulating the colonic inflammatory microenvironment through multiple processes, including the modulation of apoptosis, macrophage polarization, tight junction, mucus layer, and intestinal flora. Complemented by satisfactory anti-inflammatory and biosafety results, this nanoplatform represents a promising, effective, and safe treatment option for colitis patients.

Design strategies, advances and future perspectives of colon-targeted delivery systems for the treatment of inflammatory bowel disease

Inflammatory bowel diseases (IBD) significantly contribute to high mortality globally and negatively affect patients' qualifications of life. The gastrointestinal tract has unique anatomical characteristics and physiological environment limitations. Moreover, certain natural or synthetic anti-inflammatory drugs are associated with poor targeting, low drug accumulation at the lesion site, and other side effects, hindering them from exerting their therapeutic effects. Colon-targeted drug delivery systems represent attractive alternatives as novel carriers for IBD treatment. This review mainly discusses the treatment status of IBD, obstacles to drug delivery, design strategies of colon-targeted delivery systems, and perspectives on the existing complementary therapies. Moreover, based on recent reports, we summarized the therapeutic mechanism of colon-targeted drug delivery. Finally, we addressed the challenges and future directions to facilitate the exploitation of advanced nanomedicine for IBD therapy.

Orally administrated liquid metal agents for inflammation-targeted alleviation of inflammatory bowel diseases

Rapid drug clearance and off-target effects of therapeutic drugs can induce low bioavailability and systemic side effects and gravely restrict the therapeutic effects of inflammatory bowel diseases (IBDs). Here, we propose an amplifying targeting strategy based on orally administered gallium (Ga)-based liquid metal (LM) nano-agents to efficiently eliminate reactive oxygen and nitrogen species (RONS) and modulate the dysregulated microbiome for remission of IBDs. Taking advantage of the favorable adhesive activity and coordination ability of polyphenol structure, epigallocatechin gallate (EGCG) is applied to encapsulate LM to construct the formulations (LM-EGCG). After adhering to the inflamed tissue, EGCG not only eliminates RONS but also captures the dissociated Ga to form EGCG-Ga complexes for enhancive accumulation. The detained composites protect the intestinal barrier and modulate gut microbiota for restoring the disordered enteral microenvironment, thereby relieving IBDs. Unexpectedly, LM-EGCG markedly decreases the Escherichia_Shigella populations while augmenting the abundance of Akkermansia and Bifidobacterium, resulting in favorable therapeutic effects against the dextran sulfate sodium-induced colitis.

2D Is Better: Engineering Polydopamine into Cationic Nanosheets to Enhance Anti-Inflammatory Capability

Polydopamine nanomaterials have emerged as one of the most popular organic materials for the management of oxidative stress-mediated inflammatory diseases. However, their current anti-inflammatory ability is still unsatisfactory because of limited phenolic hydroxyl groups, and oxidation reaction-medicated reactive oxygen and nitrogen species (RONS) scavenging. Herein, via fusing dimension engineering and surface charge engineering, 2D cationic polydopamine nanosheets (PDA NSs) capable of scavenging multiple danger signals to enhance anti-inflammatory capability are reported. Compared with conventional spherical polydopamine nanoparticles, 2D PDA NSs exhibit three- to fourfold enhancement in RONS scavenging capability, which should be attributed to high specific surface area and abundant phenol groups of 2D ultrathin structure. To further enhance the anti-inflammatory ability, polylysine molecules are absorbed on the surface of PDA NSs to endow the scavenging capability of cell-free DNA (cfDNA), another typical inflammatory factor to exacerbate the pathogenesis of inflammation. Molecular mechanisms reveal that cationic PDA NSs can concurrently activate Keap1-Nrf2 and block TLR9 signaling pathway, achieving synergistical inflammation inhibition. As a proof of concept, cationic PDA NSs with RONS and cfDNA dual-scavenging capability effectively alleviate the inflammatory bowel disease in both delayed and prophylactic models, much better than the clinical drug 5-aminosalicylic acid.

Mechanism of Nicotiflorin in San-Ye-Qing rhizome for anti-inflammatory effect in ulcerative colitis

BACKGROUND

The incidence of ulcerative colitis (UC) is on the rise globally and the development of drugs targeting UC is urgent. Finding the target of action of natural products is important for drug discovery, elucidation of drug action mechanism, and disease mechanism. San-Ye-Qing (SYQ), is an ancient herbal medicine, but whether the powder of its rhizome has pharmacological effects against UC and its mechanism of action are not clear.

PURPOSE

To evaluate the therapeutic effectiveness of rhizome powder of SYQ in treating UC, and conduct an isolation and characterization of the chemical constituents of the powder. Further, screen the most potent compounds among them and determine the potential mechanism for treating UC.

METHODS

In vivo, the therapeutic effect of SYQ's rhizome powder on UC was assessed by mice's body weight, DAI score, colon length, tissue MPO activity, serum inflammatory markers, etc. Additionally, HPLC was used to isolate and identify the specific chemical components of SYQ's rhizome powder. Then, the most effective compounds and their therapeutic targets were analysed and screened in SYQ rhizome powder using network pharmacology, combined with CCK-8 assay, NO release assay and molecular docking assay, in conjunction with CETSA, DARTS, SPR and enzyme activity assay. Finally, the biological effects of the key compound on the targets were validated using Western blot and ELISA.

RESULTS

In vivo, SYQ rhizome powder effectively restored mice's body weight, lowered DAI and pathological score, downregulated the expression of inflammatory biomarkers, and restored colon length, as well as the colonic epithelial and mucus barriers. Afterward, 9 compounds were isolated and identified from the powder of the rhizomes of SYQ by HPLC. Nicotiflorin is the primary compound in SYQ with the highest concentration. According to both CCK-8 and NO release tests, Nicotiflorin is also the most efficacious compound. Combined with network pharmacological prediction, molecular docking analysis, CETSA, DARTS, SPR and enzyme activity assay, Nicotiflorin may ultimately suppress inflammation by targeting p65 and inhibiting the NF-κB pathway, thereby attenuating the activation of NLRP3 inflammasome. To verify this conclusion, Western blot and ELISA experiments were conducted.

CONCLUSIONS

Our results suggest that the extract from SYQ rhizomes has therapeutic properties for UC. Its active ingredient Nicotiflorin exerted potent anti-UC effects by binding to p65 and inhibiting the activation of NF-κB and NLRP3 inflammasomes.

Liquid exfoliation of molybdenum metallenes for non-inflammatory photothermal therapy of tumors

Tissue damage and cell death occurring during photothermal therapy (PTT) for tumors can induce an inflammatory response that is detrimental to tumor therapy. Herein, ultrathin Mo metallene nanosheets with a thickness of <5 nm prepared by liquid phase exfoliation were explored as functional hyperthermia agents for non-inflammatory ablation of tumors. The obtained Mo metallene nanosheets exhibited good photothermal conversion properties and significant reactive oxygen species (ROS) scavenging ability, thus achieving superior cancer cell ablation and anti-inflammatory effects in vitro. For in vivo experiments, 4T1 tumors were ablated while the inflammation-related cytokine levels did not obviously increase, demonstrating that the inflammatory response induced by PTT was inhibited by the anti-inflammatory properties of Mo metallene nanosheets. Moreover, Mo metallene nanosheets depicted good dispersibility and biocompatibility, beneficial for biomedical applications. This work introduces Mo metallenes as promising hyperthermia agents for non-inflammatory PTT of tumors.

Critical learning from industrial catalysis for nanocatalytic medicine

Systematical and critical learning from industrial catalysis will bring inspiration for emerging nanocatalytic medicine, but the relevant knowledge is quite limited so far. In this review, we briefly summarize representative catalytic reactions and corresponding catalysts in industry, and then distinguish the similarities and differences in catalytic reactions between industrial and medical applications in support of critical learning, deep understanding, and rational designing of appropriate catalysts and catalytic reactions for various medical applications. Finally, we summarize/outlook the present and potential translation from industrial catalysis to nanocatalytic medicine. This review is expected to display a clear picture of nanocatalytic medicine evolution.

A Gas Therapy Strategy for Intestinal Flora Regulation and Colitis Treatment by Nanogel-Based Multistage NO Delivery Microcapsules

Current approaches to treating inflammatory bowel disease focus on the suppression of overactive immune responses, the removal of reactive intestinal oxygen species, and regulation of the intestinal flora. However, owing to the complex structure of the gastrointestinal tract and the influence of mucus, current small-molecule and biologic-based drugs for treating colitis cannot effectively act at the site of colon inflammation, and as a result, they tend to exhibit low efficacies and toxic side effects. In this study, nanogel-based multistage NO delivery microcapsules are developed to achieve NO release at the inflammation site by targeting the inflammatory tissues using the nanogel. Surprisingly, oral administration of the microcapsules suppresses the growth of pathogenic bacteria and increases the abundance of probiotic bacteria. Metabolomics further show that an increased abundance of intestinal probiotics promotes the production of metabolites, including short-chain fatty acids and indole derivatives, which modulate the intestinal immunity and restore the intestinal barrier via the interleukin-17 and PI3K-Akt signaling pathways. This work reveals that the developed gas therapy strategy based on multistage NO delivery microcapsules modulates the intestinal microbial balance, thereby reducing inflammation and promoting intestinal barrier repair, ultimately providing a new therapeutic approach for the clinical management of colitis.

An olsalazine nanoneedle-embedded inulin hydrogel reshapes intestinal homeostasis in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic and refractory condition characterized by disrupted epithelial barrier, dysregulated immune balance, and altered gut microbiota. Nano-enabled interventions for restoring gut homeostasis have the potential to alleviate inflammation in IBD. Herein, we developed a combination of olsalazine (Olsa)-based nanoneedles and microbiota-regulating inulin gel to reshape intestinal homeostasis and relieve inflammation. The Olsa-derived nanoneedles exhibited reactive oxygen species scavenging ability and anti-inflammatory effects in lipopolysaccharide-simulated macrophages. The composite of nanoneedles and inulin gel (Cu2(Olsa)/Gel) displayed a macroporous structure, improved bio-adhesion, and enhanced colon retention after oral administration. Mechanistically, the composite effectively downregulated pro-inflammatory cytokine levels and promoted epithelial barrier repair through anti-inflammatory and antioxidant therapies, resulting in significant alleviation of colitis in three animal models of IBD. Furthermore, analysis of gut microbiota revealed that Cu2(Olsa)/Gel treatment increased the diversity of intestinal microflora and decreased the relative abundance of pathogenic bacteria such as Proteobacteria. Overall, this study provides a self-delivering nanodrug and dietary fiber hydrogel composite for IBD therapy, offering an efficient approach to restore intestinal homeostasis.

Nanozyme-Based Regulation of Cellular Metabolism and Their Applications

Metabolism is the sum of the enzyme-dependent chemical reactions, which produces energy in catabolic process and synthesizes biomass in anabolic process, exhibiting high similarity in mammalian cell, microbial cell, and plant cell. Consequently, the loss or gain of metabolic enzyme activity greatly affects cellular metabolism. Nanozymes, as emerging enzyme mimics with diverse functions and adjustable catalytic activities, have shown attractive potential for metabolic regulation. Although the basic metabolic tasks are highly similar for the cells from different species, the concrete metabolic pathway varies with the intracellular structure of different species. Here, the basic metabolism in living organisms is described and the similarities and differences in the metabolic pathways among mammalian, microbial, and plant cells and the regulation mechanism are discussed. The recent progress on regulation of cellular metabolism mainly including nutrient uptake and utilization, energy production, and the accompanied redox reactions by different kinds of oxidoreductases and their applications in the field of disease therapy, antimicrobial therapy, and sustainable agriculture is systematically reviewed. Furthermore, the prospects and challenges of nanozymes in regulating cell metabolism are also discussed, which broaden their application scenarios.

Molybdenum nanoparticles as a potential topical medication for alopecia treatment through antioxidant pathways that differ from minoxidil

BACKGROUND

Hair loss is a common dermatological condition including various types such as alopecia areata, androgenetic alopecia, etc. Minoxidil is a topical medication used for treating hair loss, which is effective for various types of alopecia. However, minoxidil has limitations in treating hair loss, such as slow onset of action and low efficacy, and it cannot effectively inhibit one of the major pathogenic factors of hair loss - excessive oxidative stress.

METHODS

Transition metal elements with rapid electron transfer, such as molybdenum, have been extensively studied and applied for inhibiting oxidative stress. We established a mouse model for hair growth and intervened with nano-sized molybdenum, minoxidil, and a combination of both. The physicochemical properties of nano-sized molybdenum enabled it to mediate oxidative stress more quickly.

RESULTS

The results showed that nano-sized molybdenum can accelerate hair growth, increase the number of local hair follicles, and reduce the expression of oxidative stress-related molecules such as iNOS, COX2, and androgen receptors. The combination of nano-sized molybdenum and minoxidil showed an additive effect in promoting hair growth.

CONCLUSION

Our findings suggest that nano-sized molybdenum might be a potential topical medication for treating hair loss by inhibiting the oxidative stress pathway. Nano-sized molybdenum, alone or in combination with minoxidil, could be a promising therapeutic approach for patients with hair loss, particularly those who do not respond well to current treatments. Further clinical studies are warranted to confirm the efficacy and safety of this novel treatment.

Recent Advances in Metal-Hydride-Based Disease Treatment

In comparison to traditional antioxidant treatment methods, the use of hydrogen to eliminate reactive oxygen species from the body has the advantages of high biological safety, strong selectivity, and high clearance rate. As an energy storage material, metal hydrides have been extensively studied and used in transporting hydrogen as clean energy, which can achieve a high hydrogen load and controlled hydrogen release. Considering the antioxidant properties of hydrogen and the delivery ability of metal hydrides, metal-hydride-based disease treatment strategies have attracted widespread attention. Up to now, metal hydrides have been reported for the treatment of tumors and a range of inflammation-related diseases. However, limited by the insufficient investment, the use of metal hydrides in disease treatment still has many shortcomings, such as low targeting efficiency, limited therapeutic activity, and complex material preparation process. Particularly, metal hydrides have been found to have a series of optical, acoustic, and catalytic properties when scaled up to the nanoscale, and these properties are also widely used to promote disease treatment effects. From this new perspective, we comprehensively summarize the very recent research progress on metal-hydride-based disease treatment in this review. Ultimately, the challenges and prospects of such a burgeoning cancer theranostics modality are outlooked to provide inspiration for the further development and clinical translation of metal hydrides.

Silicon-containing nanomedicine and biomaterials: materials chemistry, multi-dimensional design, and biomedical application

The invention of silica-based bioactive glass in the late 1960s has sparked significant interest in exploring a wide range of silicon-containing biomaterials from the macroscale to the nanoscale. Over the past few decades, these biomaterials have been extensively explored for their potential in diverse biomedical applications, considering their remarkable bioactivity, excellent biocompatibility, facile surface functionalization, controllable synthesis, etc. However, to expedite the clinical translation and the unexpected utilization of silicon-composed nanomedicine and biomaterials, it is highly desirable to achieve a thorough comprehension of their characteristics and biological effects from an overall perspective. In this review, we provide a comprehensive discussion on the state-of-the-art progress of silicon-composed biomaterials, including their classification, characteristics, fabrication methods, and versatile biomedical applications. Additionally, we highlight the multi-dimensional design of both pure and hybrid silicon-composed nanomedicine and biomaterials and their intrinsic biological effects and interactions with biological systems. Their extensive biomedical applications span from drug delivery and bioimaging to therapeutic interventions and regenerative medicine, showcasing the significance of their rational design and fabrication to meet specific requirements and optimize their theranostic performance. Additionally, we offer insights into the future prospects and potential challenges regarding silicon-composed nanomedicine and biomaterials. By shedding light on these exciting research advances, we aspire to foster further progress in the biomedical field and drive the development of innovative silicon-composed nanomedicine and biomaterials with transformative applications in biomedicine.

Oral Nanomedicine: Challenges and Opportunities

Compared to injection administration, oral administration is free of discomfort, wound infection, and complications and has a higher compliance rate for patients with diverse diseases. However, oral administration reduces the bioavailability of medicines, especially biologics (e.g., peptides, proteins, and antibodies), due to harsh gastrointestinal biological barriers. In this context, the development and prosperity of nanotechnology have helped improve the bioactivity and oral availability of oral medicines. On this basis, first, the biological barriers to oral administration are discussed, and then oral nanomedicine based on organic and inorganic nanomaterials and their biomedical applications in diverse diseases are reviewed. Finally, the challenges and potential opportunities in the future development of oral nanomedicine, which may provide a vital reference for the eventual clinical transformation and standardized production of oral nanomedicine, are put forward.

2D Nanozymes Modulate Gut Microbiota and T-Cell Differentiation for Inflammatory Bowel Disease Management

Intestinal commensal microbiota dysbiosis and immune dysfunction are significant exacerbating factors in inflammatory bowel disease (IBD). To address these problems, Pluronic F-127-coated tungsten diselenide (WSe2 @F127) nanozymes are developed by simple liquid-phase exfoliation. The abundant valence transitions of elemental selenium (Se2- /Se4+ ) and tungsten (W4+ /W6+ ) enable the obtained WSe2 @F127 nanozymes to eliminate reactive oxygen/nitrogen species. In addition, the released tungsten ions are capable of inhibiting the proliferation of Escherichia coli. In a model of dextran sodium sulfate-induced colitis, WSe2 @F127 nanozymes modulate the gut microbiota by increasing the abundance of bacteria S24-7 and significantly reducing the abundance of Enterobacteriaceae. Moreover, WSe2 @F127 nanozymes inhibit T-cell differentiation and improve intestinal immune barrier function in a model of Crohn's disease. The WSe2 @F127 nanozymes effectively alleviate IBD by reducing oxidative stress damage, modulating intestinal microbial populations, and remodeling the immune barrier.

Inactivation of pathogenic microorganisms in water by electron beam excitation multi-wavelength ultraviolet irradiation: Efficiency, influence factors and mechanism

Due to the limitations of traditional ultraviolet (UV) in microbial inactivation in water, it is necessary to explore a more suitable and efficient UV disinfection method. In this study, an electron beam excitation multi-wavelength ultraviolet (EBE-MW-UV) system was established and aims to analyze its differential microbial inactivation capabilities in comparison to single-wavelength UV-LEDs in waterborne applications. Furthermore, the inactivation mechanisms of this system on microorganisms were explored. The results showed that EBE-MW-UV had significantly higher inactivation effects on the Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans in water compared to UV-LEDs (p＜0.05), and the inactivation effect of EBE-MW-UV on Escherichia coli and Pseudomonas aeruginosa at the same UV dose was 3.8 and 1.9 log higher than that of UV-LEDs, respectively, EBE-MW-UV exhibited better inactivation effects on Gram-negative bacteria. Further research found that, under the majority of irradiation doses, neither EBE-MW-UV nor UV-LEDs were significantly affected by the concentration of suspended solids (5 and 20 mg/L) or humic acids (2 and 5 mg/L) in the water. Mechanism analysis revealed that during the disinfection process of EBE-MW-UV, microbial DNA and proteins were initially damaged, which prevented the occurrence of dark repair and led to bacterial inactivation. In addition, UV irradiation led to the production of additional reactive oxygen species (ROS) inside the cells, increasing cell membrane permeability and exacerbating membrane damage. This was accompanied by a decrease in energy metabolism and depletion of ATP, ultimately resulting in microbial inactivation. Therefore, EBE-MW-UV demonstrated more effective disinfection than single-wavelength UV-LEDs, showing great potential. Our research gives new insights into the characteristics of multiple wavelength ultraviolet, and provides scientific basis for the selection of new light sources in the field of ultraviolet disinfection.

The progression of inorganic nanoparticles and natural products for inflammatory bowel disease

There is a growing body of evidence indicating a close association between inflammatory bowel disease (IBD) and disrupted intestinal homeostasis. Excessive production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with an increase in M1 proinflammatory macrophage infiltration during the activation of intestinal inflammation, plays a pivotal role in disrupting intestinal homeostasis in IBD. The overabundance of ROS/RNS can cause intestinal tissue damage and the disruption of crucial gut proteins, which ultimately compromises the integrity of the intestinal barrier. The proliferation of M1 macrophages contributes to an exaggerated immune response, further compromising the intestinal immune barrier. Currently, intestinal nanomaterials have gained widespread attention in the context of IBD due to their notable characteristics, including the ability to specifically target regions of interest, clear excess ROS/RNS, and mimic biological enzymes. In this review, we initially elucidated the gut microenvironment in IBD. Subsequently, we delineate therapeutic strategies involving two distinct types of nanomedicine, namely inorganic nanoparticles and natural product nanomaterials. Finally, we present a comprehensive overview of the promising prospects associated with the application of nanomedicine in future clinical settings for the treatment of IBD (graphic abstract). Different classes of nanomedicine are used to treat IBD. This review primarily elucidates the current etiology of inflammatory bowel disease and explores two prominent nanomaterial-based therapeutic approaches. First, it aims to eliminate excessive reactive oxygen species and reactive nitrogen species. Second, they focus on modulating the polarization of inflammatory macrophages and reducing the proportion of pro-inflammatory macrophages. Additionally, this article delves into the treatment of inflammatory bowel disease using inorganic metal nanomaterials and natural product nanomaterials.

Molybdenum Nanodots for Acute Lung Injury Therapy

Acute respiratory disease syndrome (ARDS) is a common critical disease with high morbidity and mortality rates, yet specific and effective treatments for it are currently lacking. ARDS was especially apparent and rampant during the COVID-19 pandemic. Excess reactive oxygen species (ROS) production and an uncontrolled inflammatory response play a critical role in the disease progression of ARDS. Herein, we developed molybdenum nanodots (MNDs) as a functional nanomaterial with ultrasmall size, good biocompatibility, and excellent ROS scavenging ability for the treatment of acute lung injury (ALI). MNDs, which were administered intratracheally, significantly ameliorated lung oxidative stress, inflammatory response, protein permeability, and histological severity in ALI mice without inducing any safety issues. Importantly, transcriptomics analysis indicated that MNDs protected lung tissues by inhibiting the activation of the Nod-like receptor protein 3 (NLRP3)-dependent pyroptotic pathway. This work presents a promising therapeutic agent for patients suffering from ARDS.

Reactive Oxygen Species‐Activated CO Versatile Nanomedicine with Innate Gut Immune and Microbiome Remodeling Effects for Treating Inflammatory Bowel Disease

Abnormal activation of the gut mucosal immune system and a highly dysregulated gut microbiota play essential roles in the progression of inflammatory bowel disease (IBD). The clinical treatment of IBD remains highly challenging, with first‐line drugs showing limited efficacy and significant side effects. A reactive oxygen species (ROS)‐activated CO versatile nanomedicine (CMPs) capable of remodeling the gut immune‐microbiota microenvironment via potent anti‐oxidant, anti‐inflammatory, and antimicrobial effects is developed. CORM‐401‐loaded mannose‐modified peptide dendrimer nanogel: CMPs preferentially congregate on the surface of damaged colon mucosa after rectal administration and are subsequently internalized by activated immune cells. CORM‐401 can release numerous CO molecules in response to high ROS levels in cells and at the site of IBD, resulting in multiple therapeutic effects. In vitro and in vivo studies have demonstrated that CMPs scavenge ROS, suppress inflammatory responses, eliminate pathogens, and alleviate colitis in mouse models. RNA sequencing reveals that CMPs successfully remodel gut mucosal immune homeostasis by scavenging ROS, inhibiting NF‐κB/p38MAPK, activating PI3K‐Akt, and inhibiting HIF‐1‐induced glycolysis. 16S ribosomal RNA sequencing shows that CMPs can remodel the gut flora composition by restraining detrimental bacteria and augmenting beneficial bacteria. This study develops a promising and versatile nanomedicine for the management of IBD.

Orally Administered Silicon Hydrogen Nanomaterials as Target Therapy to Treat Intestinal Diseases

The occurrence and development of inflammatory bowel diseases (IBDs) are inextricably linked to the excessive production of reactive oxygen species (ROS). Thus, there is an urgent need to develop innovative tactics to combat IBDs and scavenge excess ROS from affected areas. Herein, silicon hydrogen nanoparticles (SiH NPs) with ROS-scavenging ability were prepared by etching Si nanowires (NWs) with hydrogen fluoride (HF) to alleviate the symptoms associated with IBD by orally targeting the inflamed colonic sites. The strong reductive Si-H bonds showed excellent stability in the gastric and intestinal fluids, which exhibited efficient ROS-scavenging effects to protect cells from high oxidative stress-induced death. After oral delivery, the negatively charged SiH NPs were specifically adsorbed to the positively charged inflammatory epithelial tissues of the colon for an extended period via electrostatic interactions to prolong the colonic residence time. SiH NPs exhibited significant preventive and therapeutic effects in dextran sodium sulfate-induced prophylactic and therapeutic mouse models by inhibiting colonic shortening, reducing the secretion of pro-inflammatory cytokines, regulating macrophage polarization, and protecting the colonic barrier. As determined using 16S rDNA high-throughput sequencing, the oral administration of SiH NPs treatment led to changes in the abundance of the intestinal microbiome, which improved the bacterial diversity and restored the relative abundance of beneficial bacteria after the inflamed colon. Overall, our findings highlight the broad application of SiH-based anti-inflammatory drugs in the treatment of IBD and other inflammatory diseases.

Catalytically proficient ceria nanodots supported on redox-active mesoporous hosts for treatment of inflammatory bowel disease via efficient ROS scavenging

Ceria nanozyme-based ROS scavengers have shown great potential in the treatment of inflammatory bowel disease (IBD) through microenvironment regulation. However, the currently developed nanotherapeutics suffer from difficulties in concomitantly achieving small sizes and stable interparticle dispersion which is pivotal to sufficient oxygen vacancies facilitating electron transfer and oxygen storage in the dynamic cycling of Ce3+/Ce4+ redox pairs. Herein, a hybrid nanosystem consisting of ceria nanodots supported on redox-active mesoporous hosts was developed to address the challenge of ROS scavenging, in particular the efficient downregulation of the readily renewable, highly concentrated H2O2 species. Specifically, Ce4+ ions oxidized from Ce3+ in weakly basic solution were captured and reduced in time by the abundant catechols on the mesoporous polydopamine nanoparticles. This led to strong restriction of ceria growth (∼2.8 nm) in the ion precipitation process and efficient maintenance of the Ce3+/Ce4+ ratio at a high value of 1.59 which is 4.8 fold higher than that of homogeneously nucleated ceria nanoparticles. Through this design, the nanohybrid showed an attractive catalytic performance in scavenging multiple ROS species, particularly the fast and recyclable conversion of H2O2. Thereby, significant suppression of the inflammatory cytokine/chemokine secretion was achieved by inhibiting the activation of NF-κB signaling pathways (5.1 fold higher as compared to those of pristine ceria nanoparticles), upregulating the Nrf2 signaling pathway, and reducing the proportion of M1 macrophages at IBD sites. Therapeutic efficiency was also demonstrated by the effective repair of the intestinal mucosal barrier by recovering the tight junction integrity in vivo. This study sheds light on the employment of redox-active hosts to support ceria catalysts for advancing anti-inflammation applications by boosting ROS scavenging performance.

A Biomimetic Nanoplatform with Improved Inflammatory Targeting Behavior for ROS Scavenging-Based Treatment of Ulcerative Colitis

Ulcerative colitis (UC), a refractory disease, has become a global problem. Herein, a biomimetic nanoplatform (AU-LIP-CM) comprising Au cluster enzymes (AU)-loaded liposomes (AU-LIP) camouflaged with the fusion membrane (CM) consisting of neutrophil (NC) and red blood cell (RBC) membrane is designed for the treatment of UC. Briefly, revealed by second near-infrared (NIR-II) imaging through collection of fluorescence emitting >1200 nm from AU, the improved inflammatory targeting behavior contributed by CM cloaking, which inherits abilities of inflammatory targeting and immune escape from NC and RBC, respectively, promotes specific accumulation of AU within inflammatory intestines with up to ≈11.5 times higher than that of bare AU. Afterward, AU possessing superoxide dismutase- and catalase-like activities realizes high-efficiency scavenging of reactive oxygen species (ROS), leading to repair of intestinal barriers, regulation of the immune system, and modulation of gut microbiota, which surpass first-line UC drug. In addition, study of underlying therapeutic mechanism demonstrated that the treatment with AU-LIP-CM can alter the gene signature associated with response to ROS for UC mice to a profile similar to that of healthy mice, deciphering related signal pathways. The strategy developed here provides insights of learning from properties of natural bio-substances to empower biomimetic nanoplatform to confront diseases.

Rational Design of Orally Administered Cascade Nanozyme for Inflammatory Bowel Disease Therapy

Inflammatory bowel disease (IBD) affects millions of individuals worldwide annually. Enteric reactive oxygen species (ROS) play critical roles in the physiology and pathology of IBD. Nanozymes hold great promise for the treatment of IBD because of their exceptional ability to regulate redox homeostasis during ROS-related inflammation. However, the rapid development of orally administered, acid-tolerant, antioxidant nanozymes for IBD therapy is challenging. Here, a nine-tier high-throughput screening strategy is established to address the multifaceted IBD treatment demands, including intrinsic stability, radioactivity, solubility, gut microbiome toxicity, biomimetic elements, intermediate frontier molecular orbitals, reaction energy barriers, negative charges, and acid tolerance. Ni3 S4 is selected as the best matching material from 146 323 candidates, which exhibits superoxide dismutase-catalase bienzyme-like activity and is 3.13- and 1.80-fold more active than natural enzymes. As demonstrated in a mouse model, Ni3 S4 is stable in the gastrointestinal tract without toxicity and specifically targets the diseased colon to alleviate oxidative stress. RNA and 16S rRNA sequencing analyses show that Ni3 S4 effectively inhibits the cellular pathways of pro-inflammatory factors and restores the gut microbiota. This study not develops a highly efficient orally administered cascade nanozyme for IBD therapy and offers a next-generation paradigm for the rational design of nanomedicine through data-driven approaches.

Near-Infrared-II-Driven Pollen Micromotors for Inflammatory Bowel Disease Treatment

Inflammatory bowel disease (IBD) is a common inflammatory bowel disease with a high incidence rate and serious consequences. Attempts in this area are focusing on developing efficient delivery systems for relieving IBD. Herein, we present a kind of near-infrared-II (NIR-II)-activated pollen-derived micromotor (PDMM) as an efficient delivery system for treating IBD. These PDMMs are pollen grains with half of them covered by a gold (Au) layer, which can result in an asymmetric thermal gradient around the PDMMs under NIR-II irradiation, thereby forming a thermophoretic force to drive PDMMs to move spontaneously. Besides, the inherent spiny and hollow architectures of pollen grains endowed the PDMMs with outstanding capacity of adherence and drug delivery, respectively. Based on these features, we have demonstrated that the PDMMs could move actively in vivo with the irradiation of NIR-II light and adhere to the surrounding tissues for drug delivery. Thus, the PDMMs loaded with dexamethasone show desirable curative effects on treating IBD. These results indicated that the proposed PDMM-based delivery system has great potential in clinic gastrointestinal administration.