miR-214-3p Promotes ox-LDL-Induced Macrophages Ferroptosis and Inflammation via GPX4.

Abstract

Purpose: Atherosclerosis (AS) is a chronic inflammatory disease caused by the dysregulation of lipid metabolism. It has been established that oxidized low-density lipoprotein (ox-LDL)-induced macrophage inflammation and ferroptosis play important roles in AS. However, the mechanism by which ox-LDL induces inflammation in macrophages requires further investigation.

Materials and methods: A foam cell model derived from ox-LDL-induced macrophages was constructed to study its mechanism of action. The levels of interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α were evaluated using an Enzyme-Linked Immunosorbent Assay (ELISA). Oil Red O staining was used to detect intracellular lipid accumulation levels. Lactate dehydrogenase (LDH), malondialdehyde (MDA), reactive oxygen species (ROS), and Fe²⁺ levels were assessed. Dual-luciferase and RNA-binding protein immunoprecipitation (RIP) experiments validated the binding relationship between microRNA (miR)-214-3p and glutathione peroxidase 4 (GPX4).

Results: The levels of IL-6, IL-1β, and TNF-α were significantly increased in ox-LDL-induced macrophages, accompanied by increased lipid accumulation, indicating the promotion of foam cell formation. Additionally, ox-LDL increased LDH, MDA, ROS, and Fe²⁺. The expression of miR-214-3p positively correlated with ox-LDL concentration in macrophages. Treatment with an miR-214-3p inhibitor reduces lipid accumulation, inflammatory responses, and ferroptosis in macrophages. Dual-luciferase and RIP experiments confirmed that miR-214-3p regulates GPX4 transcription. Silenced GPX4 reversed the inflammatory effects of the miR-214-3p inhibitor on ox-LDL-induced macrophages. Low GPX4 expression also increased lipid accumulation and ferroptosis in macrophages.

Conclusion: miR-214-3p promotes macrophage ferroptosis and inflammation induced by ox-LDL. This mechanism may be associated with miR-214-3p-induced GPX4 expression, which underscores the therapeutic significance of targeting macrophage inflammation and ferroptosis in addressing AS.