ROS-responsive nanomicelles encapsulating celastrol ameliorate pressure overload-induced cardiac hypertrophy by...

Celastrol (CEL) belongs to the group of non-steroidal immunosuppressants with the potential to improve cardiac hypertrophy (CH). However, the poor biocompatibility and low bioavailability of CEL limit its in vivo application. This study was aimed to develop a targeted drug delivery system that can efficiently and safely deliver CEL to target tissues, providing a research basis for the application of CEL in CH therapy. A novel ROS-sensitive drug-loaded nanomicelle, dodecanoic acid (DA)-phenylboronic acid pinacol ester-dextran polymer encapsulating CEL (DBD@CEL), was synthesized using chemical synthesis. Then, the morphology, particle size, drug-loaded content, and ROS-responsive release behavior of DBD@CEL were studied. Pharmacokinetics and biocompatibility were evaluated using healthy mice. Finally, the ability and mechanism of DBD@CEL in improving CH in vivo were investigated using a mouse CH model. DBD@CEL was successfully prepared with a drug loading of 18.9%. It exhibited excellent stability with an average particle size of 110.0 ± 1.7 nm. Within 48 h, DBD@CEL released only 19.4% in the absence of H₂O₂, while in the presence of 1 mM H₂O₂, the release rate increased to 71.5%. Biocompatibility studies indicated that DBD@CEL did not cause blood cell hemolysis, had no impact on normal organs, and did not result in abnormal blood biochemical indicators, demonstrating excellent biocompatibility. In vivo studies revealed that DBD@CEL regulated the activation of NF-κB signaling, inhibits pyroptosis and oxidative stress, and thereby ameliorates CH. The ROS-responsive DBD@CEL nanodrug delivery system enhances the therapeutic activity of CEL for CH, providing a promising drug delivery system for the clinical treatment of CH.