Abstract 175: Adiponectin Alleviates Cortical Neuronal Apoptosis Following Cardiopulmonary Resuscitation by Attenuating MiR-31-5p Carried by Brain Microvascular Endothelial Cell-Derived Extracellular Vesicles

Abstract

Background: Adiponectin (APN) is a cardiovascular-protective adipokine. Our previous research has shown that APN administration reduced cortical neuron apoptosis in mice after resuscitation. Brain microvascular endothelial cell-derived extracellular vesicles (BMEC-sEVs) have neuroprotective properties, and APN regulates BMEC-sEVs' function to alleviate neuronal apoptosis after resuscitation. However, the specific molecular mechanisms are unclear. MicroRNAs carried by sEVs play essential roles. Hypothesis: APN may alleviate cortical neuron apoptosis by regulating miRNAs carried by BMEC-sEVs. Aims: To investigate if APN attenuates cortical neuron apoptosis in mice after resuscitation by regulating BMEC-sEVs-miRNAs and to elucidate the underlying molecular mechanisms. Methods: BMEC-sEVs APN were extracted and identified. BMEC-sEVs were injected into the brain to establish a cardiopulmonary resuscitation mouse model, and cortical neuron apoptosis was assessed. Co-culture experiments were performed between BMEC-sEVs and primary cortical neurons, and apoptosis was evaluated after oxygen-glucose deprivation/reperfusion (OGD/R). Bioinformatics identified miRNAs with pro-apoptotic effects. APN-regulated specific BMEC-sEV miRNAs were screened. Overexpression and inhibition experiments confirmed the neuroprotective effects of the identified miRNA. Target genes were screened, and downstream signaling pathways were explored. Results: APN enhanced the protective effect of BMEC-sEVs against cortical neuron apoptosis. APN preconditioning reduced miR-155-5p and miR-31-5p levels in BMEC-sEVs APN . MiR-31-5p was highly expressed in primary BMECs and increased after OGD/R. Overexpression of miR-31-5p in cortical neurons aggravated neuronal apoptosis. Inhibition of miR-31-5p reduced apoptotic neurons in Adipoq -/- mice after ROSC. Map3k1 was the most affected target gene of miR-31-5p, and its regulatory role in cortical neuron apoptosis was confirmed. Conclusion: APN alleviates cortical neuron apoptosis after resuscitation by downregulating miR-31-5p expression in BMEC-sEVs; BMEC-sEVs APN alleviate cortical neuron apoptosis through the miR-31-5p/MAP3K1 signaling pathway.