Anti-inflammatory activity of creatine supplementation in endothelial cells in vitro.

1 Creatine (CR) supplementation augments muscle strength in skeletal muscle cells by increasing intracellular energy pools. However, the effect of CR supplementation on endothelial cells remains to be clarified. 2 In this study, we investigated whether CR supplementation had any anti-inflammatory activity against human pulmonary endothelial cells in culture. 3 We confirmed that supplementation with 0.5 mM CR significantly increased both intracellular CR and phosphocreatine (PC) through a CR transporter while keeping intracellular ATP levels constant independent of CR supplementation and a CR transporter antagonist. 4 In the assay system of endothelial permeability, supplementation with 5 mM CR significantly suppressed the endothelial permeability induced by serotonin and H(2)O(2). 5 In cell adhesion experiments, supplementation with 5 mM CR significantly suppressed neutrophil adhesion to endothelial cells. 6 In the measurement of adhesion molecules, CR supplementation with more than 0.5 mM CR significantly inhibited the expressions of ICAM-1 and E-selectin on endothelial cells, and the inhibition was significantly suppressed by an adenosine A(2A) receptor antagonist. 7 The present study suggests that CR supplementation has anti-inflammatory activities against endothelial cells.