METTL3 mediates atheroprone flow-induced glycolysis in endothelial cells

Atheroprone flow-increased glycolysis in vascular endothelial cells (ECs) is pivotal in EC dysfunction and the initiation of atherosclerosis. Methyltransferase 3 (METTL3) is a major m⁶A methyltransferase for RNA N6-mehtyladenosine (m⁶A) modifications to regulate epitranscriptome and cellular functions. With the atheroprone flow upregulating METTL3 and m⁶A RNA hypermethylation, we investigate the role of METTL3 in atheroprone flow-induced glycolysis in ECs in vitro and in vivo. Compared to pulsatile shear stress (PS, atheroprotective flow), oscillatory shear stress (OS, atheroprone flow) increases METTL3 expression to enhance the m⁶A modifications of mRNAs encoding HK1, PFKFB3, and GCKR, which are rate-limiting enzymes of glycolysis. These augmented m⁶A modifications increase the expressions of HK1 and PFKFB3 while decreasing GCKR, resulting in elevated EC glycolysis, as revealed by seahorse analysis. Moreover, a stimulated Raman scattering (SRS) imaging study demonstrates the elevation of glucose incorporation into de novo synthesized lipids in ECs under atheroprone flow in vitro and in vivo. Empagliflozin, a sodium-glucose cotransporter-2 inhibitor (SGLT2i) drug, represses METTL3 expression, thereby mitigating OS-induced glycolysis in ECs. These data suggest mechanisms by which METTL3 links EC mechanotransduction with metabolic reprogramming under atherogenic conditions.