DanShen Decoction targets miR-93-5p to provide protection against MI/RI by regulating the TXNIP/NLRP3/Caspase-1 signaling pathway.

Background: Bone marrow mesenchymal stem cells (BMSCs) derived exosomes have demonstrated potential therapeutic efficacy on myocardial ischemia/reperfusion injury (MI/RI). This study has explored the underlying mechanisms of Danshen decoction (DSD) pretreated BMSCs-exosomes to treat MI/RI in vivo and in vitro.

Methods: Extracellular vesicles extracted from BMSCs were identified, miRNA sequencing was performed to screen the effects of DSD, and verified to target TXNIP in vivo. After MI/RI modeling, rats were treated with BMSCs-exosomes pretreated with DSD or miRNA inhibitor. BMSCs-exosomes, DSD-pretreated BMSCs-exosomes, and miRNA inhibitor/anti-miRNA-pretreated BMSCs-exosomes were used to treat H9c2 cells or MI/RI rats. CCK-8, Tunnel staining, and flow cytometry were performed to measure cell viability. LDH, CK, CK-MB were detected to evaluate cell injury. MDA, SOD, and ROS were used to confirm oxidative stress. Furthermore, IL-1β, IL-18, cleaved-caspase-1, pro-caspase-1, NLRP3, TXNIP, and GSDMD were quantified for the TXNIP/NLRP3/Caspase-1 signaling activation. In addition, echocardiography was used to observe the heart function, and H&E stain was performed to detect pathological injury.

Results: Following DSD pretreatment, there was a marked elevation in the expression levels of miR-93-5p, miR-16-5p, and miR-15b-5p, with miR-93-5p exhibiting the highest baseMean value. The administration of a miR-93-5p inhibitor yielded effects counteractive to those observed with DSD treatment, leading to reduced cell proliferation, heightened oxidative stress (as indicated by increased levels of SOD and ROS, alongside a decrease in MDA), and enhanced cell apoptosis. Furthermore, DSD effectively mitigated the miR-93-5p-induced upregulation of key inflammatory and apoptotic markers, including IL-1β, IL-18, caspase-1, NLRP3, TXNIP, and GSDMD. Notably, exosomes derived from DSD-pretreated BMSCs demonstrated a capacity to alleviate cardiac damage.

Conclusion: DSD may target miR-93-5p within BMSC-derived exosomes to confer protection against cardiac damage by inhibiting the activation of the TXNIP/NLRP3/Caspase-1 signaling pathway, thereby mitigating cardiomyocyte pyroptosis. This study provides a theoretical foundation for the application of DSD in the treatment of MI/RI.