Background and objectives: Marinobufagenin (MBG) is a cardiotonic steroid that is increased in preeclampsia. An analog of MBG, resibufogenin (RBG), prevents the development of preeclampsia in a rat model. Oxidative stress is a concomitant of endothelial dysfunction in the latter disorder. The objective of the current studies was to evaluate the status of oxidative stress in a rat model of preeclampsia.
Methods: We measured the aortic AT(1) receptor expression and urinary excretion of 8-isoprostane (8IP) in rats rendered "preeclamptic" and compared the findings to those obtained in normal pregnant animals, pregnant rats injected with MBG, and preeclamptic rats treated with RBG.
Results: Aortic AT(1) receptor expression and the urinary excretion of 8IP were significantly augmented in "preeclamptic" and MBG-injected pregnant rats compared to normal pregnant animals. RBG prevented evidence of oxidative stress in "preeclamptic" rats.
Conclusion: MBG is involved in the causation of oxidative stress in our rat model and RBG attenuates this change.