Role of NR4A1-Caveolin-1 Axis in the Orchestration of Mitophagy During Macrophage Senescence.

Background/aims: Arteriosclerosis (AS) remains a leading cause of global mortality, with macrophage senescence playing a crucial role in its progression. Senescent macrophages, characterized by oxidative stress and inflammation, exhibit dysregulated mitophagy. However, the underlying mechanisms remain unclear.

Methods: This study explores the role of caveolin-1, a structural protein of caveolae, in NR4A1-mediated mitophagy during oxLDL-induced macrophage senescence. Using gene knockdown and overexpression models, we assessed mitochondrial dysfunction, ROS production, cytokine secretion, and mitophagy activity in murine macrophages.

Results: It revealed that NR4A1 promoted mitochondrial dysfunction and senescence through enhanced ROS production and disrupted mitochondrial potential. Caveolin-1 mediated this effect by facilitating NR4A1-induced mitophagy, as evidenced by colocalization of mitochondria and lysosomes and the activation of Parkin-related pathways. NR4A1 upregulated caveolin-1 expression, forming a signaling axis critical for senescence-associated pro-inflammatory cytokine production.

Conclusion: Overall, our study unraveled The NR4A1-caveolin-1 axis orchestrates mitophagy and inflammation in senescent macrophages, shedding light on AS pathogenesis and suggesting potential therapeutic targets to mitigate macrophage-driven inflammation and oxidative stress.