Sanguinarine inhibits deep venous thrombosis by suppressing platelets TLR4 and reducing the release of platelets-derived HMGB1

Background: Deep vein thrombosis (DVT) is a common Cardiovascular Disease associated with considerable health burden, involved in inflammatory. Beside of coagulation factor, platelets also play a pivotal role in DVT. However, strategy target to platelets in DVT was limited. Sanguinarine (SA), an active ingredient extracted from poppy Plants, has shown promising anti-platelets effect, whereas its potential therapeutic mechanism on DVT remains largely unknown. We aimed to investigate the therapeutic effects and the underlying mechanisms of SA on DVT.

Methods: Firstly, the inferior vena cava (IVC) models were utilized to modify DVT progress. Then, network pharmacology, molecular simulation, flow cytometry and western blot were employed to elucidate the mechanisms underlying. Also, loxP-Cre transgenic mice were used to confirm the targetability of SA in vivo. Finally, transwell assay and immunofluorescence staining was used to detect neutrophils migration and neutrophil extracellular traps (NETs) formation.

Results: We found that SA administration dose-dependently inhibited DVT formation, and decreased NETs formation in vivo. Molecular simulation and cellular thermal shift assay suggested that SA directly binds to TLR4/MD2. Furthermore, the antithrombotic effects of SA disappeared in platelets specific TLR4 deficient mice. Mechanistically, SA suppressed TLR4/αIIbβ3 signaling and reduced HMGB1 externalization in platelets. Moreover, platelets TLR4 activation induced neutrophils recruitment and NETs formation by releasing HMGB1, SA abolished this progress.

Conclusion: In summary, SA mitigates DVT by inhibiting platelets-derived HMGB1 release through the inhibition of TLR4 signaling. This suggests that SA holds promise as a therapeutic agent for DVT.