Compound Dan Zhi tablet attenuates experimental ischemic stroke via inhibiting platelet activation and thrombus formation

Background: Compound Dan Zhi tablet (DZT) is a commonly used traditional Chinese medicine formula. It has been used for the treatment of ischemic stroke for many years in clinical. However, its pharmacological mechanism is unclear.

Purpose: The aim of the current study was to understand the protective effects and underlying mechanisms of DZT on ischemic stroke.

Methods: Fifteen representative chemical markers in DZT were determined by ultra-performance liquid chromatography coupled with tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). The protective effect of DZT against ischemic stroke was studied in a rat model of middle cerebral artery occlusion (MCAO), and the mechanism was further explored through a combination of network pharmacology and experimental verification.

Results: Quantitative analysis showed that the contents of phenolic acids, furan sulfonic acids, tanshinones, flavonoids, saponins and phthalides in DZT were calculated as 7.47, 0.788, 0.627, 0.531 and 0.256 mg/g, respectively. Phenolic acids were the most abundant constituents. Orally administered DZT (1.701 g kg^-1) significantly alleviated the infarct size and neurological scores in MCAO rats. The network analysis predicted that 53 absorbed active compounds in DZT-treated plasma targeted 189 proteins and 47 pathways. Ten pathways were associated with anti-platelet activity. In further experiments, DZT (0.4 and 0.8 mg mL^-1) markedly inhibited in vitro prostaglandin G/H synthase 1 (PTGS1) activity. DZT (0.4 and 0.8 mg mL^-1) significantly inhibited in vitro platelet aggregation in response to ADP or AA. DZT (113 and 226 mg kg^-1, p.o.) also produced a marked inhibition of ADP- or AA-induced ex vivo platelet aggregation with a short duration of action. DZT decreased the level of thromboxane A₂ (TXA₂) in MCAO rats. In the carrageenan-induced tail thrombosis model and ADP-induced acute pulmonary thromboembolism mice model, DZT (113 and 226 mg kg^-1, p.o.) prevented thrombus formation. Importantly, DZT (113 and 226 mg kg^-1, p.o.) exhibited a low bleeding liability.

Conclusion: DZT protected against cerebral ischemic injury. The inhibition of TXA₂ level, platelet aggregation and thrombosis formation might involve in the protective mechanism.