The aryl hydrocarbon receptor (AhR) plays a crucial role in regulating many physiological processes. Activating the AhR–CYP1A1 axis has emerged as a novel therapeutic strategy against various inflammatory diseases. Here, a practical in situ cell-based fluorometric assay was constructed to screen AhR-CYP1A1 axis modulators, via functional sensing of CYP1A1 activities in live cells. Firstly, a cell-permeable, isoform-specific enzyme-activable fluorogenic substrate for CYP1A1 was rationally constructed for in-situ visualizing the dynamic changes of CYP1A1 function in living systems, which was subsequently used for discovering the efficacious modulators of the AhR–CYP1A1 axis. Following screening of a compound library, LAC-7 was identified as an efficacious activator of the AhR–CYP1A1 axis, which dose-dependently up-regulated the expression levels of both CYP1A1 and AhR in multiple cell lines. LAC-7 also suppressed macrophage M1 polarization and reduced the levels of inflammatory factors in LPS-induced bone marrow-derived macrophages. Animal tests showed that LAC-7 could significantly mitigate DSS-induced ulcerative colitis and LPS-induced acute lung injury in mice, and markedly reduced the levels of multiple inflammatory factors. Collectively, an optimized fluorometric cell-based assay was devised for in situ functional imaging of CYP1A1 activities in living systems, which strongly facilitated the discovery of efficacious modulators of the AhR–CYP1A1 axis as novel anti-inflammatory agents.

The transition of cancer cells from epithelial state to mesenchymal state awarded hepatocellular carcinoma (HCC) stem cell properties and induced tumorigenicity, drug resistance, and high recurrence rate. Reversing the mesenchymal state to epithelial state by inducing mesenchymal–epithelial remodeling could inhibit the progression of HCC. Using high-throughput screening, chrysin was selected from natural products to reverse epithelial-mesenchymal transition (EMT) by selectively increasing CDH1 expression. The target identification suggested chrysin exerted its anti-HCC effect through covalently and specifically binding threonine 205 (Thr205) of alpha-enolase (ENO1). For the first time, we revealed that ENO1 bound β-catenin mRNA, and recruited YTHDF2 to identify the m6A modified β-catenin in the 3＇-UTR region to degrade β-catenin mRNA. Eventually, the CDH1 gene expression was improved through the regulation of β-catenin mRNA. ENO1/β-catenin mRNA interaction might be a promising target for cellular plasticity reprogramming. Moreover, chrysin could mediate mesenchymal‒epithelial remodeling through increasing degradation of β-catenin mRNA by promoting the binding of ENO1 and β-catenin mRNA. To the best of our knowledge, chrysin is the first reported small molecule inducing β-catenin mRNA degradation through binding to ENO1. The water-soluble derivative of chrysin may be a natural product-derived lead compound for circumventing metastasis, recurrence, and drug resistance of HCC by mediating mesenchymal‒epithelial remodeling.

Ferroptosis has received great attention as an iron-dependent programmed cell death for efficient cancer therapy. However, with the accumulation of iron in tumor cells, the antioxidant system is activated by reducing glutathione (GSH) with glutathione peroxidase 4 (GPX4), which critically limits the ferroptosis therapeutic effect. Herein, an iron and GPX4 silencing siRNA (siGPX4) co-encapsulated ferritin nanocage (HFn@Fe/siGPX4) was developed to enhance ferroptosis by disruption of redox homeostasis and inhibition of antioxidant enzyme synergistically. The siGPX4 were loaded into the nanocages by pre-incubated with iron, which could significantly improve the loading efficiency of the gene drugs when compared with the reported gene drug loading strategy by ferritin nanocages. And more iron was overloaded into the ferritin through the diffusion method. When HFn@Fe/siGPX4 was taken up by human breast cancer cell MCF-7 in a TfR1-mediated pathway, the excess iron ions in the drug delivery system could for one thing induce ferroptosis by the production of reactive oxygen species (ROS), for another promote siGPX4 escaping from the lysosome to exert gene silencing effect more effectively. Both the in vitro and in vivo results demonstrated that HFn@Fe/siGPX4 could significantly inhibit tumor growth by synergistical ferroptosis. Thus, the developed HFn@Fe/siGPX4 afforded a combined ferroptosis strategy for ferroptosis-based antitumor as well as a novel and efficient gene drug delivery system.

Clopidogrel effectively inhibits platelet aggregation in response to ADP by irreversibly binding to the platelet P2Y₁₂ receptor through its active metabolite. However, the observed discrepancies between the pharmacokinetics (PK) and pharmacodynamics (PD) of clopidogrel present substantial challenges in individualizing of antiplatelet therapy. To address these challenges, a robust liquid chromatography–tandem mass spectrometry method has been developed to facilitate the real-time assessment of platelet P2Y₁₂ receptor occupancy. This method has been validated in animal models, providing a reliable link between individual PK profiles and PD effects. Target receptor occupancy offers a comprehensive overview of interindividual variations in clopidogrel metabolism, regulation of P2Y₁₂ receptor expression, and platelet turnover. Moreover, it directly correlates with the inhibitory effect on platelet aggregation. The levels of platelet P2Y₁₂ occupancy accurately reflect the extent of clinical factors influencing the PD of clopidogrel, including dosage, drug–drug interactions (DDI), and type 2 diabetes mellitus (T2DM). As a normalized metric, platelet P2Y₁₂ occupancy not only serves potential as a diagnostic tool for personalized clopidogrel therapy but also aids in elucidating the role of the P2Y₁₂ signaling pathway in cases of abnormal on-treatment platelet reactivity.

Ischemia-reperfusion (I/R) injury following skin flap transplantation is a critical factor leading to flap necrosis and transplant failure. Antagonizing inflammatory responses and oxidative stress are regarded as crucial targets for mitigating reperfusion injury and enhancing flap survival. In this study, caffeic acid-vanadium metal polyphenol nanoparticles (CA-V NPs) were prepared for the treatment of skin flap ischemia and reperfusion. This study was conducted using a one-step method to prepare new types of CA-V NPs with uniform sizes and stable structures. In vitro, the CA-V NPs exhibited CAT-like and SOD-like activities and could effectively scavenge ROS, generate oxygen, and alleviate oxidative stress. In the H₂O₂-induced cellular oxidative stress model, CA-V NPs effectively reduced ROS levels and inhibited apoptosis through the XIAP/Caspase-3 pathway. In the cellular inflammation model induced by LPS combined with IFN-γ, CA-V NPs reprogrammed macrophage polarization toward the M2 phenotype and reduced inflammatory responses by reducing the expression of the chemokines CCL4 and CXCL2. In addition, animal experiments have shown that CA-V NPs can alleviate oxidative stress in skin flap tissues, inhibit apoptosis, promote angiogenesis, and ultimately improve the survival rate of skin flaps. CA-V NPs provide a new target and strategy for the treatment of flap I/R injury.

The underlying cause of low response rates to existing immunotherapies is that tumor cells dominate tumor immune escape through surface antigen deficiency and inducing tumor immunosuppressive microenvironment (TIME). Here, we proposed an in situ tumor cell engineering strategy to disrupt tumor immune escape at the root by restoring tumor cell MHC-I/tumor-specific antigen complex (MHC-I/TSA) expression to promote T-cell recognition and by silencing tumor cell CD55 to increase the ICOSL⁺ B-cell proportion and reverse the TIME. A doxorubicin (DOX) and dual-gene plasmid (MAC pDNA, encoding both MHC-I/ASMTNMELM and CD55-shRNA) coloaded drug delivery system (LCPN@ACD) with tumor targeting and charge/size dual–conversion properties was prepared. LCPN@ACD-induced ICD promoted DC maturation and enhanced T-cell activation and infiltration. LCPN@ACD enabled effective expression of MHC-I/TSA on tumor cells, increasing the ability of tumor cell recognition and killing. LCPN@ACD downregulated tumor cell CD55 expression, increased the proportion of ICOSL⁺ B cells and CTLs, and reversed the TIME, thus greatly improving the efficacy of αPD-1 and CAR-T therapies. The application of this in situ tumor cell engineering strategy eliminated the source of tumor immune escape, providing new ideas for solving the challenges of clinical immunotherapy.

Elevated glucose metabolism is a prominent characteristic of fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA). However, the efficacy of inhibiting a single target of glucose metabolism in FLS using small molecular inhibitors is limited for RA treatment. Herein, the synergistic inhibition of FLS’ survival, proliferation, and activation by combining two glucose metabolism inhibitors, diclofenac (DC) and lonidamine (LND) was first verified. Subsequently, DC and LND were individually conjugated to cystamine-modified hyaluronic acid (HA) to prepare two polymer-prodrug conjugates. A HAP-1 peptide-modified dual polymer-prodrug conjugates-assembled nanoparticles system (^HAP–1NP_DC+LND) was further tailored in the optimal synergistic ratio for targeted and synergistic metabolic modulation of FLS to alleviate RA symptoms. Upon targeted uptake by FLS in inflamed joints, HAP^–1NP_DC+LND released DC and LND within the intracellular reductive microenvironment, where DC hinders glucose uptake and LND suppresses glycolytic enzymes to eliminate FLS synergistically. Additionally, the secretion of lactic acid and pro-inflammatory factors from FLS were reduced, thereby disrupting the crosstalk between FLS and pro-inflammatory macrophages. Finally, ^HAP–1NP_DC+LND demonstrated promising efficacy in a mouse model of collagen-induced arthritis (CIA). Overall, this research provides valuable insights into novel therapeutic strategies for the safe and effective of treatment RA through targeted and synergistic metabolic modulation of FLS.

Mitochondrial dysfunction in chondrocytes is a key pathogenic factor in osteoarthritis (OA), but directly modulating mitochondria in vivo remains a significant challenge. This study is the first to verify a correlation between mitochondrial dysfunction and the downregulation of the FOXO3 gene in the cartilage of OA patients, highlighting the potential for regulating mitophagy via FOXO3 gene modulation to alleviate OA. Consequently, we developed a chondrocyte-targeting CRISPR/Cas9-based FOXO3 gene-editing tool (FoxO3) and integrated it within a nanoengineered ‘truck’ (NETT, FoxO3--NETT). This was further encapsulated in injectable hydrogel microspheres (FoxO3-NETT@SMs) to harness the antioxidant properties of sodium alginate and the enhanced lubrication of hybrid exosomes. Collectively, these FoxO3-NETT@SMs successfully activate mitophagy and rebalance mitochondrial function in OA chondrocytes through the Foxo3 gene-modulated PINK1/Parkin pathway. As a result, FoxO3-NETT@SMs stimulate chondrocytes proliferation, migration, and ECM production in vitro, and effectively alleviate OA progression in vivo, demonstrating significant potential for clinical applications.

In current clinical practice, various dermal templates and skin substitutes are used to enhance wound healing. However, the role of wound commensal microbiome in regulating scaffold performance and the healing process remains unclear. In this study, we investigated the influence of both natural and synthetic scaffolds on the wound commensal microbiome and wound repair in three distinct models including diabetic wounds, burn injuries, and germ-free (GF) wounds. Remarkably, synthetic electrospun polycaprolactone (PCL) scaffolds were observed to positively promote microbiome diversity, leading to enhanced diabetic wound healing compared to the natural scaffolds Integra^® (INT) and MatriDerm^® (MAD). In contrast, both natural and synthetic scaffolds exhibited comparable effects on the diversity of the microbiome and the healing of burn injuries. In GF wounds with no detectable microorganisms, a reversed healing rate was noted showing natural scaffold (MAD) accelerated wound repair compared to the open or the synthetic scaffold (PCL) treatment. Furthermore, the response of the wound commensal microbiome to PCL scaffolds appears pivotal in promoting anti-inflammatory factors during diabetic wound healing. Our results emphasize that the wound commensal microbiome, mediated by different scaffolds plays an important role in the wound healing process.