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.

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.