We explored how eicosapentaenoic acid (EPA), a type of omega-3 fatty acid, affects arteriosclerosis, specifically by examining its active metabolite, 17,18-epoxyeicosatetraenoic acid (17,18-EEQ). Our investigation revealed that 17,18-EEQ has the power to inhibit inflammation and endothelial activation, which are key factors in the development of atherosclerosis.
We found that this metabolite works through its interaction with a specific receptor, sphingosine-1-phosphate receptor 1 (S1PR1), in endothelial cells. In our study, when using male mice that lacked S1PR1, the protective effects of both 17,18-EEQ and purified EPA were noticeably absent. This emphasizes the importance of S1PR1 in mediating the benefits of EPA.
Mechanistically, we discovered that 17,18-EEQ promotes the activation of endothelial nitric oxide synthase (eNOS), which is vital for maintaining healthy blood vessels. This activation relies on a signaling pathway involving calcium release. We also noted that a prescription drug containing purified EPA, called Vascepa, exhibited cardiovascular benefits through this 17,18-EEQ-S1PR1 pathway.
Collectively, our findings highlight the potential of EPA and its metabolites as valuable tools in combating atherosclerosis, which could pave the way for new therapeutic strategies aimed at improving cardiovascular health.