Fig 1: FAIM3 was confirmed as a direct target of miR-344b-5p and exerted antagonistic effects in miR-344b-5p mediated IH-induced cells damage.A Relative FAIM3 expression was measure by qRT-PCR after transfecting pcDNA3.1 or pcDNA3.1-FAIM3. B Relative miR-344b-5p expression was measure by qRT-PCR after transfecting pcDNA3.1 or pcDNA3.1-FAIM3. C Relative FAIM3 expression was measure by qRT-PCR after transfecting miR-344b-5p mimic or mimics NC. D, E Relative FAIM3 protein expression was measure by western blot after transfecting miR-344b-5p mimic or mimics NC. F Luciferase reporter assay. Cells were co-transfected with FAIM3-wt or FAIM3-mut 3'-UTR reporters and miR-344b-5p mimic or mimics NC. G, H miR-344b-5p mimic (or mimics NC) and pcDNA3.1-FAIM3 (or pcDNA3.1) were co-transfected into H9c2 cells. Cells were treated with IH for six cycles. EdU staining assay was performed to evaluate the proliferation of H9c2 cells, scale bar 50 µm. I Hoechst 33342/PI staining was performed to evaluate the apoptosis of H9c2 cells. miR-344b-5p mimic (or mimics NC) and pcDNA3.1-FAIM3 (or pcDNA3.1) were co-transfected into H9c2 cells, scale bar 50 µm. Cells were treated with IH for six cycles. J, K miR-344b-5p mimic (or mimics NC) and pcDNA3.1-FAIM3 (or pcDNA3.1) were co-transfected into H9c2 cells. Cells were treated with IH for six cycles. Expression levels of FAIM3 and apoptosis-related proteins (Bcl-2, Bax, and Cleaved caspase-3/Caspase-3) by western blot. *P < 0.05, **P < 0.001, ***P < 0.0001, ****P < 0.00001. Data were shown as Mean ± SD based on three independent experiments.