Electroacupuncture regulates FTO/Nrf2/NLRP3 axis-mediated pyroptosis in cerebral ischemia-reperfusion injury

Electroacupuncture (EA) demonstrates neuroprotective in cerebral ischemia-reperfusion (I/R) injury. N6-methyladenosine (m6A) is found to contribute to the pathogenesis of neurological conditions recently. The objective of this study is to investigate the effects of EA on m6A and related mechanism in cerebral I/R injury. After the middle cerebral artery occlusion/reperfusion (MCAO/R) operation was used to establish rat models with cerebral I/R injury, EA was applied to Baihui (GV20) and Dazhui (GV14) once daily for 7 consecutive days. Subsequently, the modified Neurological Severity Score, 2,3,5-triphenyltetrazolium chloride staining, and hematoxylin and eosin staining were performed to assess the neurological damage. To investigate the potential target, the total RNA m6A level and relevant regulators (METTL3, METTL14, WTAP, FTO, and ALKBH5) were examined. In the next step, FTO, Nrf2, NLRP3, IL-18, IL-1β, and TUNEL-positive rates were detected, while the shRNA-FTO was administered to suppress FTO expression. EA improved neurobehavioral disorders, infarct volume, and pathological damage induced by cerebral I/R injury. Mechanically, EA reduced the total RNA m6A level by selectively regulating FTO, but not METTL3, METTL14, WTAP, and ALKBH5. Furthermore, EA could enhance Nrf2 and suppress NLRP3, IL-18, IL-1β, and TUNEL-positive rates, which was reversed by the shRNA-FTO injection. Our findings indicate that EA may alleviate FTO/Nrf2/NLRP3 axis-mediated pyroptosis in cerebral I/R injury, providing a more unified understanding of the neuroprotective effects of EA. Specifically, EA intervention appears to promote the expression of FTO, leading to a reduction of m6A level, which activates Nrf2 and subsequently suppresses NLRP3-mediated pyroptosis.