RGD1564534 represses NLRP3 inflammasome activity in cerebral injury following ischemia-reperfusion by impairing miR-101a-3p-mediated Dusp1 inhibition.

BACKGROUND

Mitochondrial autophagy, the elimination of damaged mitochondria through autophagy, contributes to neuron survival in cerebral ischemia. Long non-coding RNAs (lncRNAs)/microRNAs (miRNAs)/mRNAs are important regulatory networks implicated in various biological processes, including cerebral ischemia-reperfusion (I/R) injury. Therefore, this work clarifies a novel RGD1564534-mediated regulatory network on mitochondrial autophagy in cerebral I/R injury.

METHODS

Differentially expressed lncRNAs in cerebral I/R injury were predicted by bioinformatics analysis. Expression of RGD1564534 was examined in the established middle cerebral artery occlusion (MCAO) rats and oxygen glucose deprivation/reoxygenation (OGD/R)-exposed neurons. We conducted luciferase activity, RNA pull-down and RIP assays to illustrate the interaction among RGD1564534, miR-101a-3p and Dusp1. Gain- or loss-of-function approaches were used to manipulate RGD1564534 and Dusp1 expression. The mechanism of RGD1564534 in cerebral I/R injury was evaluated both in vivo and in vitro.

RESULTS

RGD1564534 was poorly expressed in the MCAO rats and OGD/R-treated cells, while its high expression attenuated nerve damage, cognitive dysfunction, brain white matter and small vessel damage in MCAO rats. In addition, RGD1564534 promoted mitochondrial autophagy and inhibited NLRP3 inflammasome activity. RGD1564534 competitively bound to miR-101a-3p and attenuated its binding to Dusp1, increasing the expression of Dusp1 in neurons. By this mechanism, RGD1564534 enhanced mitochondrial autophagy, reduced NLRP3 inflammasome activity and suppressed the neuron apoptosis induced by OGD/R.

CONCLUSION

Altogether, RGD1564534 elevates the expression of Dusp1 by competitively binding to miR-101a-3p, which facilitates mitochondrial autophagy-mediated inactivation of NLRP3 inflammasome and thus retards cerebral I/R injury.