Diosmin alleviates NLRP3 inflammasome-dependent cellular pyroptosis after stroke through RSK2/CREB pathway

In the context of our previous analyses on the main active ingredients of Jieyudan, a classic formula targeting aphasia in stroke, we further delve into the function and mechanisms of its active ingredient, Diosmin (DM), which may exert neuroprotective effects, in ischemic stroke. Herein, bioinformatics analysis revealed targets of DM and their intersection with differentially expressed genes in ischemic stroke. Middle cerebral artery occlusion (MCAO) rats and oxygen-glucose deprivation (OGD) cells were used to construct in vivo and in vitro models of ischemic stroke. The effects of DM on MCAO rats were assessed by Zea-Longa score, Morris water maze, TTC staining, Nissl staining, immunohistochemistry, and Western blot. At the cellular level, cell counting kit-8 assay and Western blot were carried out to verify the mechanism of DM in ischemic stroke. In vivo, DM decreased neurological deficit score, cerebral infarct volume and neuronal damage, and improved cognitive function in MCAO rats. In vitro, DM increased the viability of OGD-treated cells. In addition, DM down-regulated the expressions of NLR family pyrin domain containing 3 (NLRP3) and pyroptosis-associated proteins, while up-regulating ribosomal protein S6 kinase A3 (RSK2) level and activating cyclic-AMP response element-binding protein (CREB) signaling. Conversely, RSK2 inhibitor LJH685 reduced the viability and promoted pyroptosis-associated protein levels, which also partially reversed the effects of DM in vitro. Collectively, DM plays a therapeutic role in ischemic stroke by inhibiting NLRP3 inflammasome-mediated cellular pyroptosis via the RSK2/CREB pathway.