Inhibition of miR-200b-3p alleviates lipid accumulation and promotes cholesterol efflux by targeting ABCA1 in macrophage-derived foam cells

Abstract

Atherosclerosis (As) is a chronic cardiovascular disease characterized by abnormal of lipid accumulation and cholesterol efflux. The present study aimed to investigate whether the micro-RNA (miR)-200b-3p could exacerbate As by promoting lipid accumulation and inhibiting cholesterol efflux via ATP-binding cassette transporter A1 (ABCA1) in macrophage-derived foam cells. Blood samples from 30 patients with As and 30 healthy people were collected at Quanzhou First Hospital. RAW264.7 cells were used to establish foam cells using oxidized low-density lipoprotein. The expression of miR-200b-3p and ABCA1 was evaluated by reverse transcription quantitative PCR and western blotting. Lipid accumulation was analyzed by Oil Red O staining and cholesterol content was assessed by ELISA. A targeting relationship between miR-200b-3p and ABCA1 was demonstrated by luciferase reporter assays. Compared with healthy volunteers and RAW264.7 cells, the expression level of miR-200b-3p was significantly increased whereas the expression level of ABCA1 was significantly decreased in patients with As and foam cells. Furthermore, miR-200b-3p expression was negatively correlated with ABCA1 expression in the blood of the patients with As. Lipid content was significantly decreased and cholesterol efflux was significantly increased in foam cells transfected with the miR-200b-3p inhibitor compared with inhibitor control cells. In addition, ABCA1 was shown to be targeted by miR-200b-3p. Furthermore, the lipid content in foam cells transfected with the miR-200b-3p inhibitor and small interfering-ABCA1 was significantly increased, while the cholesterol efflux was significantly decreased compared with foam cells transfected with the miR-200b-3p inhibitor. In conclusion, the findings from the present study indicated that inhibition of miR-200b-3p may alleviate lipid accumulation and promote cholesterol efflux by targeting ABCA1 in macrophage-derived foam cells.