The aim of the study was to investigate the expression of miR-223 and FAM5C in the peripheral blood mononuclear cells (PBMCs) of cerebral infarction patients with or without diabetes. Sixteen cases with diabetes mellitus (DM), 14 cases with cerebral infarction (CI), 12 cases with cerebral infarction and diabetes mellitus (CIDM), and 18 healthy subjects were included in this study. Real-time PCR was used to quantify mRNA expression. Western blot was used to detect FAM5C protein level. Recombinant plasmids expressing miR-223-3p and 3' UTR of FAM5C were constructed. Dual-luciferase reporter system was used to analyze the binding of miR-223-3p to FAM5C 3' UTR. FAM5C mRNA and protein level were significantly higher in the PBMCs of CIDM patients compared with healthy controls (P < 0.05). miR-223-3p expression in PBMCs was significantly lower in DM patients than in healthy controls (P < 0.05). The expression of miR-223-3p was negatively correlated with FAM5C mRNA in all patients and healthy controls. Co-transfection of miR-223-3p plasmid with FAM5C 3'UTR dual-luciferase plasmid significantly inhibited the luciferase activity (P < 0.01). FAM5C, but not miR-223, is a risk factor for CI in type 2 DM patients.
Keywords: Cerebral infarction; Diabetes; FAM5C; miR-223.