Abstract 476: Kawasaki Disease, Metabolic Switch, And Endothelial Dysfunction

Abstract

Kawasaki Disease (KD) induces endothelial dysfunction, in part, through down-regulation of miR-483. Metabolic reprogramming, including increased glycolysis and reduced oxidative phosphorylation, is associated with endothelial cell (EC) dysfunction. However, whether metabolic reprogramming is involved in KD-induced EC dysfunction is unknown. Using RNA-seq and pathway analyses, we determined that genes involved in glycolysis were upregulated by sera from acute KD patients compared with convalescent control sera. We validated by qPCR and found increased mRNA levels of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), hexokinase 1 (HK1), and hexokinase 3 (HK3), as well as the decrease in glucokinase regulator (GCKR) in cultured ECs incubated with acute KD sera. Moreover, PFKFB3 protein level was elevated in ECs cultured with acute KD sera and in the intima of coronary arteries of mice with LCWE-induced KD vasculitis. Seahorse assay revealed that KD sera increased extracellular acidification rate (ECAR) and decreased oxygen consumption rate (OCR) in ECs, indicating that serum factors in acute KD patients increased glycolysis and impaired mitochondrial function. Given the presence of a miR-483 targeting site in the 3’ untranslated region (3’UTR) of PFKFB3 mRNA, we cloned a PFKFB3-3’UTR luciferase reporter (PFKFB3-Luc) to test whether PFKFB3 is regulated by miR-483. As anticipated, miR-483 overexpression downregulated luciferase activity in ECs transfected with PFKFB3-Luc. Moreover, miR-483 overexpression decreased PFKFB3 and ECAR in ECs. In contrast, anti-miR-483 increased PFKFB3 and ECAR levels, which phenocopied acute KD-induced EC metabolic reprogramming. We conclude that glycolysis in ECs is augmented during the acute phase of KD, which promotes EC dysfunction. Mechanistically, the acute KD-associated metabolic switch in ECs is regulated, at least in part, by increased PFKFB3 as a consequence of reduced level of miR-483.