9-Methylfascaplysin exerts anti-ischemic stroke neuroprotective effects via the inhibition of neuroinflammation and oxidative stress in rats

Objectives This study was aimed to investigate the neuroprotective effects of 9-methylfascaplysin, a novel marine derivative derived from sponge, against middle cerebral artery occlusion/reperfusion (MCAO)-induced motor impairments, neuroinflammation and oxidative stress in rats. Methods Neurological and behavioral tests were used to evaluate behavioral changes. The 2, 3, 5-triphenyltetrazolium chloride staining was used to determine infarct size and edema extent. Activated microglia/macrophage was analyzed by immunohistochemical staining of Iba-1. RT-PCR and ELISA were used to measure the expression of inducible nitric oxide synthase, tumor necrosis factor-α, interleukin-1β, CD16 and CD206. Western blotting analysis was performed to explore the activation of nuclear factor-κB (NF-κB) and NLRP3. The levels of oxidative stress were studied by evaluating the activities of superoxide dismutase, catalase and glutathione peroxidase. Results Post-occlusion intracerebroventricular injection of 9-methylfascaplysin significantly attenuated motor impairments and infarct size in MCAO rats. Moreover, 9-methylfascaplysin reduced the activation of microglia/macrophage in ischemic penumbra as evidenced by the decreased Iba-1-positive area and the reduced expression of pro-inflammatory factors. Furthermore, 9-methylfascaplysin inhibited MCAO-induced oxidative stress and activation of NF-κB and NLRP3 inflammasome. Conclusion All the results suggested that 9-methylfascaplysin might produce neuroprotective effects against MCAO via the reduction of oxidative stress and neuroinflammation, simultaneously, possibly via the inhibition of NF-κB and NLRP3 inflammasome.