Effects of circRNA OMA1-plasmid or miR-654-3p mimic on HT-29 cell viability, apoptosis, and inflammatory response. Control-plasmid, circRNA OMA1-plasmid, mimic control, or miR-654-3p mimic was transfected into HT-29 cells for 24 h. Subsequently, the cells were exposed to 2% DSS for 24 d. Cells were divided into six groups: control, DSS, DSS + control-plasmid, DSS + circRNA OMA1-plasmid, DSS + circRNA OMA1-plasmid + mimic control, or DSS + circRNA OMA1-plasmid + miR-654-3p mimic. A, B qRT-PCR analysis of circRNA OMA1 and miR-654-3p mRNA levels. C Cell viability was determined by MTT assay. D Flow cytometry analysis of cells apoptosis. E Quantification of apoptotic cells. F and G Western blot analysis of cleaved caspase-3. The secretion of TNF-α (H), IL-1β (I), and IL-6 (J) was determined by ELISA. **P < 0.01