Expression of protein kinase SGK1 in preeclampsia placenta tissue and effects of hypoxia on the expression of SGK1 in placental trophoblast cells

Abstract:

Objectives：To study the expression and distribution of SGK1 in preeclampsia placenta tissues，and to explore the effects of hypoxia on the expression of SGK1 in placental trophoblast cells. Methods：Twenty-five cases of normal pregnancies，mild pre-eclampsia and severe preeclampsia were chosen，and all of these cases were delivered by cesarean section in The Second Affiliated Hospital of Chongqing Medical University from 2012 December to 2013 November. The expression level of SGK1 in placenta was detected by immunohistochemistry and Western blot. HTR-8/SVneo cells were cultured in normoxia conditions（21% O2、5% CO2） and hypoxic conditions（1% O2、5% CO2）. The expression level of SGK1 in human trophoblast cells was detected by Western blot. Results：lmmunohistochemistry revealed that the expression level of SGK1 in mild preeclampsia group and severe preeclampsia group was higher than that in control group（P=0.000）. The expression level of SGK1 in severe preeclampsia group was higher than that in mild pre-eclampsia group（P=0.028）. Western blot revealed that the protein expression level of SGK1 in mild pre-eclampsia group and severe preeclampsia group was higher than that in control group（P=0.000）. The protein expression level of SGK1 in severe preeclamp－sia was higher than that in mild pre-eclampsia group（P=0.000）. Masson staining revealed that normal placenta tissue existed fibrosis，and the extent of fibrosis was increased in mild pre-eclampsia group and severe preeclampsia group（P=0.000）. The extent of fibrosis in severe preeclampsia was higher than mild pre-eclamp－sia group（P=0.000）. In vitro，Western blot revealed that hypoxia increased SGK1 and CTCF transcription in HTR-8/SVneo cells（P=0.000；P=0.001），and masson staining revealed that hypoxia increased the production of collagen fibers（P=0.000）. Conclusion：Expression of SGK1 in preeclampsia placenta tissue is significantly increased，suggesting that SGK1 may play an important role in the pathogenesis of preeclampsia，hypoxia increased by stimulating the expression of SGK1，involved in preeclampsia.