Sulfasalazine for the treatment of preeclampsia in a nitric oxide synthase antagonist mouse model

Abstract

Introduction: Development of a therapeutic that targets the pathophysiological elements of preeclampsia would be a major advance for obstetrics, with potential to save the lives of countless mothers and babies. We recently identified anti-inflammatory drug sulfasalazine as a prospective candidate therapeutic for treatment of preeclampsia. In primary human cells and tissues in vitro, sulfasalazine potently decreased secretion of anti-angiogenic sFlt-1 and sENG, increased production of pro-angiogenic PlGF, mitigated endothelial dysfunction, and promoted whole vessel vasodilation.

Methods: Using nitric oxide synthase antagonist Nω-Nitro-l-arginine methyl ester hydrochloride, a preeclampsia-like phenotype was induced in pregnant mice, including high blood pressure, fetal growth restriction, and elevated circulating sFlt-1. Mice were treated with sulfasalazine or vehicle from gestational day (D)13.5, with blood pressure measurements across gestation, fetal measurements at D17.5, and wire myograph assessment of vasoactivity.

Results: Sulfasalazine had a modest effect on blood pressure, decreasing diastolic and mean blood pressure on D13.5, but not later in gestation, or systolic blood pressure. Sulfasalazine was not able to rescue fetal growth, in male or female fetuses. There was a suggestion of improved vasoactivity with sulfasalazine, but further clarification is required.

Discussion: In this mouse model of preeclampsia, sulfasalazine did not sustain reductions in blood pressure nor affect fetal parameters of size and weight, both desirable attributes of a viable preeclampsia therapeutic. While these data suggest sulfasalazine might improve vasoactivity, murine toxicity considerations limited the dose range of sulfasalazine that could be tested in the current study.

Keywords: Fetal growth restriction; Hypertension; Preeclampsia; Sulfasalazine; Vasoactivity.