Xing-nao-sheng-jiang powder alleviates ischemic stroke in rats by inhibiting pyroptosis-related microglial ETosis: An emerging perspective on microglial ETosis.

BACKGROUND

Stroke imposes a substantial global health burden. Microglial pyroptosis promotes acute cerebral ischemia. Gasdermin D (GSDMD), the principal executor of pyroptosis, has been implicated in a newly characterized form of proinflammatory cell death known as extracellular trap death (ETosis). Thus, targeting GSDMD may represent a promising therapeutic strategy to mitigate ischemic stroke. Xing-nao-sheng-jiang powder (XNSJP) was demonstrated to inhibit GSDMD-mediated pyroptosis in cerebral ischemia-reperfusion injury (CIRI). Based on these findings, we hypothesize that XNSJP may inhibit pyroptosis-related ETosis by targeting the GSDMD, thereby alleviating neuroinflammation in CIRI.

METHODS

We prepared the MCAO model in SD rats and evaluated the effects of XNSJP on anti-CIRI. The effects of XNSJP on microglia and neutrophil pyroptosis and ETosis were detected. The composition of XNSJP was identified using UPLC and MS/MS methods.

RESULTS

UPLC identified the characteristic peaks of XNSJP's active ingredients. MS/MS and network pharmacology suggested that XNSJP has regulatory effects on atherosclerosis, coagulation, and inflammation. The XNSJP reduced the area of infarction. XNSJP could inhibit the caspase-1/11/GSDMD-mediated pyroptosis. Furthermore, XNSJP impeded microglial pyroptosis-related ETosis by GSDMD, as evidenced by the suppression of MPO, PAD4, and CitH3. We also confirmed that 24 h after CIRI, the ETosis marker CitH3 mainly co-localized with microglia.

CONCLUSIONS

We confirmed that microglia are crucial contributors to ETosis in CIRI. Furthermore, we demonstrated that XNSJP inhibited microglial pyroptosis and ETosis against CIRI, which is closely related to the inhibition of GSDMD. Mechanistically, XNSJP inhibits caspase-1/11/GSDMD-mediated microglial pyroptosis and MPO/PAD4/CitH3-mediated microglial ETosis.