The Effect of Immune Factors, Tumor Necrosis Factor- , and Agonistic Autoantibodies to the Angiotensin II Type I Receptor on Soluble fms-Like Tyrosine-1 and Soluble Endoglin Production in Response to Hypertension During Pregnancy

• Published in: American journal of hypertension Vol. 23; no. 8; pp. 911 - 916
• Main Authors: Parrish, M. R., Murphy, S. R., Rutland, S., Wallace, K., Wenzel, K., Wallukat, G., Keiser, S., Ray, L. F., Dechend, R., Martin, J. N., Granger, J. P., LaMarca, B.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.08.2010
• ISSN: 0895-7061; 1941-7225
• DOI: 10.1038/ajh.2010.70

Preeclampsia is considered a disease of immunological origin associated with abnormalities in inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha), and activated lymphocytes secreting autoantibodies to the angiotensin II receptor (AT1-AA). Recent studies have also demonstrated that an imbalance of angiogenic factors, soluble fms-like tyrosine kinase (sFlt-1), and sEndoglin, exists in preeclampsia; however, the mechanisms that initiate their overproduction are unclear. To determine the role of immune regulation of these factors, circulating and placental sFlt-1 and/or sEndoglin was examined from pregnant rats chronically treated with TNF-alpha or AT1-AA. On day 19 of gestation blood pressure was analyzed and serum and tissues were collected. Placental villous explants were excised and cultured on matrigel coated inserts for 24 h and sFlt-1 and sEndoglin was measured from media. In response to TNF-alpha-induced hypertension, sFlt-1 increased from 180 +/- 5 to 2,907 +/- 412 pg/ml. sFlt-1 was also increased from cultured placental explants of TNF-alpha induced hypertensive pregnant rats (n = 12) (2,544 +/- 1,132 pg/ml) vs. explants from normal pregnant (NP) rats (n = 12) (2,189 +/- 586 pg/ml) where as sEng was undetectable. Circulating sFlt-1 increased from 245 +/- 38 to 3,920 +/- 798 pg/ml in response to AT1-AA induced hypertension. sFlt-1 levels were higher (3,400 +/- 350 vs. 2,480 +/- 900 pg/ml) in placental explants from AT1-AA infused rats (n = 12) than NP rats (n = 7). In addition, sEndoglin increased from 30 +/- 2.7 to 44 +/- 3.3 pg/ml (P < 0.047) in AT1-AA infused rats but was undetectable in the media of the placental explants. These data suggest that immune factors may serve as an important stimulus for both sFlt-1 and sEndoglin production in response to placental ischemia.