N6-methyladenosine demethylases Alkbh5/Fto regulate cerebral ischemia-reperfusion injury

Kaiwei Xu; Yunchang Mo; Dan Li; Qimin Yu; Lu Wang; Feihong Lin; Chang Kong; Meita Felicia Balelang; Anqi Zhang; Sijia Chen; Qinxue Dai; Junlu Wang

doi:10.1177/2040622320916024

N⁶-methyladenosine demethylases Alkbh5/Fto regulate cerebral ischemia-reperfusion injury

Ther Adv Chronic Dis. 2020 Apr 29:11:2040622320916024. doi: 10.1177/2040622320916024. eCollection 2020.

Authors

Kaiwei Xu¹, Yunchang Mo¹, Dan Li¹, Qimin Yu¹, Lu Wang¹, Feihong Lin¹, Chang Kong¹, Meita Felicia Balelang¹, Anqi Zhang¹, Sijia Chen¹, Qinxue Dai², Junlu Wang³

Affiliations

¹ Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
² Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
³ Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325035, China Wencheng County People's Hospital, Wenzhou, Zhejiang, China.

Abstract

Background: Although N⁶-methyladenosine (m⁶A) plays a very important role in different biological processes, its function in the brain has not been fully explored. Thus, we investigated the roles of the RNA demethylases Alkbh5/Fto in cerebral ischemia-reperfusion injury.

Methods: We used a rat model and primary neuronal cell culture to study the role of m⁶A and Alkbh5/Fto in the cerebral cortex ischemic penumbra after cerebral ischemia-reperfusion injury. We used Alkbh5-shRNA and Lv-Fto (in vitro) to regulate the expression of Alkbh5/Fto to study their regulation of m⁶A in the cerebral cortex and to study brain function after ischemia-reperfusion injury.

Results: We found that RNA m⁶A levels increased consecutive to the increase of Alkbh5 expression in both the cerebral cortex of rats after middle cerebral artery occlusion, and in primary neurons after oxygen deprivation/reoxygenation. In contrast, Fto expression decreased after these perturbations. Our results suggest that knocking down Alkbh5 can aggravate neuronal damage. This is due to the demethylation of Alkbh5 and Fto, which selectively demethylate the Bcl2 transcript, preventing Bcl2 transcript degradation and enhancing Bcl2 protein expression.

Conclusion: Collectively, our results demonstrate that the demethylases Alkbh5/Fto co-regulate m⁶A demethylation, which plays a crucial role in cerebral ischemia-reperfusion injury. The results provide novel insights into potential therapeutic mechanisms for stroke.

Keywords: Alkbh5; Bcl2; Fto; MCAO; OGD/R; RNA methylation; cerebral ischemia-reperfusion injury; m6A.