Severe respiratory inflammation or viral infections can lead to acute lung injury (ALI), a disease characterized by diffuse inflammatory injury of the pulmonary epithelium and endothelium. Cepharanthine (CEP) is reported as a promising drug candidate due to its antiviral properties. However, CEP exhibits poor solubility and low bioavailability. Therefore, we developed a novel liposome, named CEP@LP-M^CCR2, which integrates the advantages of cell membranes and lipid materials, to achieve effective accumulation of CEP in inflamed lungs. It exhibits a 1.73-fold increase in lung accumulation at 24 h in vivo, a 4.56-fold increase in cellular uptake in MLE-12 cells. CEP@LP-M^CCR2 is equipped with a CCR2-overexpressed surface, enabling it to selectively neutralize elevated levels of CCL2, which is related to ALI, thereby reducing macrophage infiltration, thereby reducing the spread of inflammation, such as a reduction in levels of key pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6). CEP@LP-M^CCR2 could suppress M1 macrophage polarization, which led to a marked decrease in iNOS and an increase in Arg1. It upregulated the expression of junctional proteins E-cadherin and Occludin, indicating potential recovery of the pulmonary epithelial barrier. RNA sequencing analysis implied the potential of CEP@LP-M^CCR2 to inactivate the TNF/NF-κB signaling axis.

Rhizoma coptidis (RC), known as Huang Lian, is widely used for treating diabetes in Traditional Chinese Medicine. G protein-coupled bile acid receptor 1 (TGR5) is a potential therapeutic target for glucose-lipid metabolic disorders due to its capacity to stimulate glucagon-like peptide-1 (GLP-1) secretion. However, whether RC contains ingredients targeting TGR5 remains unclear. In this study, we screened 330 secondary metabolites of RC via molecular docking and identified obacunone as a top candidate. We confirmed binding using Cell Membrane Chromatography (CMC) and quantified affinity via Surface Plasmon Resonance (SPR), determining a KD of 101 μM. cAMP assays identified obacunone as an activator of TGR5. Subsequently, concentration-dependent cAMP assays characterized it as a partial agonist with an EC50 of 9.6 μM. Finally, transcriptomic profiling revealed a stress adaptation response, identifying Heme Oxygenase 1 (HMOX1) as the most significantly upregulated gene (padj = 9.99 × 10⁻⁷², log₂FoldChange = 1.65). These findings contribute to understanding the pharmacological profile of RC and provide a screening example for identifying components with GPCR activity in RC.

Benzylisoquinoline alkaloids (BIAs) exhibit diverse biological activities, such as neuroprotective effects. The delta-opioid receptor (DOR) has emerged as a promising therapeutic target due to its potential role in enhancing neuroprotection and regeneration. However, reports on the binding of BIAs to the DOR remain scarce. Here, neferine, a BIA from Nelumbo nucifera, as a potential DOR agonist. Molecular docking ranked neferine among the top of 15 BIAs. Initial binding was detected by cellular membrane chromatography and quantitatively confirmed by bio-layer interferometry, with a K_D value of 37.4 μM. ONE vector G protein Optical biosensor revealed that G_i2, G_i3 and G_Z signaling could be activated by neferine through DOR modulation. Consistent with the G_i/z activation, neferine dose-dependently inhibited cAMP accumulation with an EC₅₀ of 0.25 µM. Transcriptomic analysis in DOR-overexpressing HEK293T cells indicated that neferine stimulation predominantly regulates gene networks governing cell cycle and stress adaptation. However, direct transcriptional signature for neuroprotection was not predominant in our system, suggesting that DOR signaling may exhibit context-dependent effects. In conclusion, we identified the neferine as a natural DOR agonist through in silico and in vitro approach, providing a reference for further investigation into its pharmacological potential.

Background: The C-X-C chemokine receptor type 7 (CXCR7), also known as atypical chemokine receptor 3 (ACKR3), primarily signals through β-arrestin and plays a pivotal role in tumor progression, inflammation, and neurodegenerative diseases. CXCR7 antagonists block chemokine binding and dampen β-arrestin signaling. Accordingly, identification of such antagonists is highly desirable for therapeutic development against CXCR7 driven pathologies. Methods: Through microscale thermophoresis (MST) screening of a Food and Drug Administration (FDA)-approved drug library, entacapone was identified as a CXCR7 binder. The NanoBit complementation assay was employed to evaluate the effect of entacapone on CXCR7 mediated β-arrestin 1/2 recruitment. Molecular docking was performed to predict the binding pocket and binding sites. Results: Entacapone specifically bound to CXCR7 with a Kd value of 6.04 µM. Although entacapone did not directly activate CXCR7, it selectively inhibited CXCL12 and VUF11207 induced β-arrestin 1 recruitment with no significant effect on β-arrestin 2 recruitment. Molecular docking suggested that entacapone interacted with key residues via hydrophobic contacts, including Trp100, Phe124, Gln301, and Leu305, and formed hydrogen bonds with Ser103, Asn108, and Tyr51 in the transmembrane core, collectively suggesting a possible binding mode compatible with stabilizing the receptor in an inactive conformation. Conclusions: Entacapone, a clinically well established COMT inhibitor, is reported for the first time as a novel biased antagonist of CXCR7, providing a new candidate molecule for drug repurposing.