Genistein-3′-sodium sulfonate ameliorates cerebral ischemia injuries by blocking neuroinflammation through the α7nAChR-JAK2/STAT3 signaling pathway in rats

Abstract

BackgroundNeuroinflammation plays a pivotal role in the acute progression of cerebral ischemia/reperfusion injury (I/RI). We previously reported that genistein-3′-sodium sulfonate (GSS), a derivative from the extract of the phytoestrogen genistein (Gen), protects cortical neurons against focal cerebral ischemia. However, the molecular mechanism underlying the neuroprotective effects exerted by GSS remains unclear. PurposeThe present study focused on the anti-inflammatory effects of GSS following I/RI in rats. Study designRandomized controlled trial. MethodsThe tMCAO rat model and LPS-stimulated BV2 in vitro model were used. Longa's scare was used to observe neurological function. TTC staining and Nissl staining were used to evaluate brain injury. ELISA, qRT-PCR, Western blotting and immunofluorescent staining methods were used to detect cytokine concentration, mRNA level, protein expression and location. ResultsGSS treatment improves neurological function, reduces the volume of cerebral infarction, attenuates proinflammatory cytokines and inactivates the phosphorylation of JAK2 and STAT3 in I/RI rats. Furthermore, GSS increased the expression of α7nAChR. More importantly, the neuroprotective, anti-inflammatory and inhibiting JAK2/STAT3 signaling pathway effects of GSS were counteracted in the presence of alpha-bungarotoxin (α-BTX), an α7nAChR inhibitor, suggesting that α7nAChR is a potential target associated with the anti-inflammatory effects of GSS in the I/RI rats. GSS also inhibited BV2 cells from releasing IL-1β via the α7nAChR pathway after LPS stimulation. ConclusionGSS protects against cerebral I/RI through the expression of α7nAChR and inhibition of the JAK2/STAT3 pathway. Our findings provide evidence for the role of the cholinergic anti-inflammatory pathway in neuroinflammation and uncover a potential novel mechanism for GSS treatment in ischemic stroke. The downstream signals of GSS, α7nAChR- JAK2/STAT3 could also be potential targets for the treatment of I/RI.