[Retracted] Exosomal miR-27b-3p Derived from Hypoxic Cardiac Microvascular Endothelial Cells Alleviates Rat Myocardial Ischemia/Reperfusion Injury through Inhibiting Oxidative Stress-Induced Pyroptosis via Foxo1/GSDMD Signaling

Figure 4

miR-27b-3p in hypoxic CMEC-derived exosomes attenuates H/R-induced injury and pyroptosis in H9C2 cells by targeting Foxo1. (a) The relative expression of Foxo1 in H9C2 cellular model under different treatments (). (b) The predictive targeting site of miR-27b-3p at the 3UTR region of Foxo1 gene. Prediction was conducted in Targetscan Human database. (c) The Dual-Luciferase Reporter assay reported the interaction between Foxo1 and miR-27b-3p (). (d) The relative expression of Foxo1 in H9C2 cellular model in response to Foxo1 overexpression (). (e) Overexpression of Foxo1 decreased miR-27b-3p expression in the H9C2 H/R cell model (). This result shows a negative feedback between miR-27b-3p and Foxo1. (f) Overexpression of Foxo1 decreased the protective effects of exosomes on the cell viability of the H9C2 H/R cell model (). (g) Fluorescence analysis for the effect of the uptake of PKH67-labeled exosomes to the cytoskeleton of the H9C2 cell model with pretreatment of Foxo1 plasmids.  μm. (h) Western blot analysis of the expression of Foxo1 protein and pyroptosis-related proteins. (i) Overexpression Foxo1 upregulated the production of lactate dehydrogenase (LDH), interleukin- (IL-) 1β, and IL-18 in the supernatant fluid of the H9C2 H/R cell model in response to exsomes (). H/R: hypoxia/reoxygenation (2 h hypoxia: 5% CO₂ and 95% N₂ and 4 h normal condition: 95% air plus 5% CO₂). Caspase-1. EXO: exosomes. NC-EXO or inhibitor-EXO indicated exosomes were derived from CMECs with pretreatment of negative control (NC) or miR-27b-3p inhibitor in hypoxic conditions.

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