Abstract: BACKGROUND: Gastrodin has anti-inflammatory effects and is mainly used in clinical practice for the treatment of ischemic stroke, and its mechanism of action is still unclear.
OBJECTIVE: To explore the mechanism of gastrodin intervention on inflammatory injury in ischemic stroke rats.
METHODS: Fifty Sprague-Dawley rats were divided into sham-operated group, model group, positive control group, high-dose gastrodin group and low-dose gastrodin group by the randomized numerical method, with 10 rats in each group. Ischemic stroke models were established by the middle cerebral artery occlusion method in all groups of rats except for the sham operation group. Administration in each group started on the 3rd day after surgery, and the rats in the positive control group were intraperitoneally injected with edaravone injection (6 mg/kg), the rats in the high- and low-dose gastrodin groups were intraperitoneally injected with 50 and 10 mg/kg gastrodin injection respectively, and the rats in the sham-operated and model groups were intraperitoneally injected with the equal volume of physiological saline. After 14 days of continuous treatment in each group, the pathological changes in rat brain tissue were observed, and the positive expression of NLRP3 inflammasome and the expression of inflammatory response-related proteins and their mRNAs were detected.
RESULTS AND CONCLUSION: Compared with the sham-operated group, the volume of cerebral infarction became larger in the model group; the structure of brain tissue was loose, irregular cavities could be observed, and the number of neurons was reduced and irregularly arranged; the positive expression of NLRP3 inflammasome increased (P < 0.01); and the protein and mRNA expression levels of Toll-like receptor 4, myeloid differentiation factor 88, apoptosis-associated speck-like protein containing a caspase-recruitment domain, Caspase-1, and interleukin-1β increased (P < 0.01). Compared with the model group, the volume of cerebral infarction became smaller in the high- and low-dose gastrodin groups; the neurons were regularly arranged, increased in number, and uniformly distributed; the positive expression of NLRP3 inflammasome was decreased (P < 0.05); the protein and mRNA expression levels of Toll-like receptor 4, myeloid differentiation factor 88, apoptosis-associated speck-like protein containing a caspase-recruitment domain, Caspase-1, and interleukin-1β were decreased in the high-dose gastrodin group (P < 0.01); Toll-like receptor 4 protein expression showed no significant changes in the low-dose gastrodin group, and the protein and mRNA expression of the other inflammatory response-associated factors decreased (P < 0.05, P < 0.01). To conclude, gastrodin attenuates inflammatory injury in ischemic stroke rats, and its mechanism of action may be related to the inhibition of inflammatory response-associate factor expression.

Key words: ischemic stroke, gastrodin, NLRP3, inflammation response, inflammatory factor, rat