Effects of simvastatin, rosuvastatin and pravastatin on soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sENG) secretion from human umbilical vein endothelial cells, primary trophoblast cells and placenta

Abstract

Background: Preeclampsia is associated with the placental release of soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sENG). These anti-angiogenic factors cause hypertension and multi-organ injury. Pravastatin decreases placental secretion of sFlt-1 in vitro and is currently being examined in clinical trials as a potential treatment for preeclampsia. However, it is possible that different classes of statins may be more potent at decreasing sFlt-1 secretion. We compared the relative potency of three different generations of statins on sFlt-1 and sENG secretion from human endothelial cells, trophoblast cells, and placenta explants.

Methods: We performed functional experiments using primary human umbilical vein endothelial cells, trophoblast cells and preterm preeclamptic placental explants to assess the affect of simvastatin, rosuvastatin and pravastatin on sFlt-1 and sENG secretion and compared the relative potency of each statin at reducing these factors (Inhibitory Concentration 50). Furthermore we assessed the effect of each statin on the antioxidant and cytoprotective enzyme, heme-oxygenase 1.

Results: All statins reduced sFlt-1 secretion from endothelial cells, trophoblasts and preterm preeclamptic placental explants. Simvastatin was the most potent inhibitor of sFlt-1 secretion from endothelial cells (IC 50 3.2 μM), trophoblast cells (IC 50 61.4 μM) and placental explants. Simvastatin was 28 times and 3 times more potent at reducing sFlt-1 secretion from endothelial cells and 85 times and 33 times more potent at reducing sFlt-1 secretion from trophoblast cells than pravastatin or rosuvastatin respectively. All statins increased sENG secretion from endothelial cells however did not change secretion from placental explants. While all statins up-regulated heme-oxygenase 1 in endothelial cells, only simvastatin up-regulated its expression in placenta from patients with preterm preeclampsia.

Conclusion: Simvastatin may be a more potent inhibitor of sFlt-1 secretion from endothelial cells, trophoblast cells and placenta from women with preterm preeclampsia than either pravastatin or rosuvastatin.

Keywords: Preeclampsia; Pregnancy; Soluble endoglin; Statins; sFlt-1.

Fig. 1

Effects of statins on sFlt-1 secretion and mRNA expression of isoforms e15a and i13 expression in primary HUVECs. a Simvastatin (0, 1, 2, 5 μM) rosuvastatin (0, 1, 2, 5 μM) and pravastatin (0, 2, 5, 200 μM) reduce sFlt-1 secretion from primary HUVECs. b Inhibitory concentration of sFlt-1 at 50 % (IC50) for simvastatin, rosuvastatin and pravastatin was determined. c Pravastatin, simvastatin and rosuvastatin reduce sFlt-1 e15a mRNA expression from primary HUVECs. d Simvastatin reduces sFlt-1 i13 mRNA expression from HUVECs whilst pravastatin and rosuvastatin have no effect. Data represents n = 3 separate experiments and is expressed as mean ± SEM. Dark blue bars = control, light blue bars = statin treatments. b = p < 0.01, d = p < 0.0001

Fig. 2

Effect of statins on sFlt-1 secretion and sFlt-1 e15a and i13 mRNA expression from placental tissues. a Simvastatin (0, 5, 50, 100 μM), rosuvastatin (0, 50, 100, 200, 300 μM) and pravastatin (0, 20, 200, 2000 μM) reduce sFlt-1 secretion from primary trophoblasts. b Inhibitory concentration of simvastatin, rosuvastatin and pravastatin was determined. c Simvastatin (100 μM) and pravastatin (2000 μM) significantly reduced sFlt-1 secretion from placental explants obtained from patients with preterm preeclampsia however rosuvastatin had no effect. d Pravastatin reduced sFlt-1 e15a mRNA expression from placental explants whilst simvastatin and rosuvastatin had no effect. Data represents n = 3-4 separate experiments and is expressed as mean ± SEM. Dark blue bars = control, light blue bars = statin treatments. a = p < 0.05, b = p < 0.01, d = p < 0.0001

Fig. 3

Effect of statins on soluble endoglin secretion from primary human tissues. a Simvastatin (0, 1, 2, 5 μM), rosuvastatin (0, 1, 2, 5, μM) and pravastatin (0, 2, 5, 200 μM) all caused an increase in soluble endoglin secretion from primary HUVECs. b Statin treatment did not alter sEng secretion from preterm preeclamptic explants. Data represents n = 3–4 separate experiments and is expressed as mean ± SEM. Dark blue bars = control, light blue bars = statin treatments. a = p < 0.05, b = p < 0.01, d = p < 0.0001

Fig. 4

Effect of statins on heme-oxygenase 1 mRNA expression. a Simvastatin (0, 5 μM), rosuvastatin (0, 5 μM) and Pravastatin (0, 200 μM) up-regulated heme-oxygenase 1 expression by HUVECs. b Simvastatin 100 μM up-regulated heme-oxygenase 1 in preeclamptic placental explants, whist pravastatin 2000 μM and rosuvastatin 100 μM had no significant effect. Data represents n = 3–4 separate experiments and is expressed as mean ± SEM. Dark blue bars = control, light blue bars = statin treatments. a = p < 0.05, c = p < 0.001, d = p < 0.0001