SIRT1 and preeclampsia: Serum SIRT1 levels was decreased in patients with severe preeclampsia (p < 0.0001), arterial blood flow velocity peak-to-trough ratio, pulsatility index and resistance index were increased (p < 0.001; p < 0.0001), and serum SIRT1 levels and uterine artery hemodynamic parameters were closely related to disease severity (p < 0.001; p < 0.0001).