Inhaled tea polyphenol-loaded nanoparticles coated with platelet membranes largely attenuate asthmatic inflammation.

Background: Tea polyphenols (TPs), prominent constituents of green tea, possess remarkable antioxidant and anti-inflammatory properties. However, their therapeutic potential is limited due to low absorption and poor bioavailability. To address this limitation and enhance their efficacy, we developed a biomimetic nanoplatform by coating platelet membrane (PM) onto poly-lactic-co-glycolic acid (PLGA) nanoparticles (NPs) to create targeted delivery vehicles for TPs (PM@TP/NPs) to the inflamed tissues in asthma.

Methods: After synthesizing and characterizing PM@TP/NPs, we assessed their biocompatibility and biosafety through cell viability assays, hemolysis tests, and inflammation analysis in vivo and in vitro. The therapeutic effect of PM@TP/NPs on asthma was then evaluated using a mouse model of HDM-induced asthma. Additionally, PM@TP/NPs-mediated reactive oxygen species (ROS) scavenging capacity, as well as the activation of signaling pathways, were analyzed in HBE cells and asthmatic mice via flow cytometry, RT-qPCR, and western blotting.

Results: Compared with free TPs, PM@TP/NPs demonstrated excellent biocompatibility and safety profiles in both in vitro and in vivo, as well as enhanced retention in inflamed lungs. In HDM-induced mouse asthma model, inhaled PM@TP/NPs largely attenuated lung inflammation and reduced the secretion of type 2 pro-inflammatory cytokines in the lungs compared to free TPs. The therapeutic effects of PM@TP/NPs on asthma might be associated with an enhanced ROS scavenging capacity, increased activation of the Nrf2/HO-1 pathway, and decreased activation of the CCL2/MAPK and TLR4/NF-κB pathway in the lungs.

Conclusions: Our findings demonstrate that inhalation of PM@TP/NPs largely attenuated lung inflammation in HDM-induced asthmatic mice. These results suggest that PM@TP/NPs might be a novel therapeutic strategy for asthma.