Purpose: Progesterone receptor membrane component 1 (PGRMC1) have anti-inflammatory and anti-apoptotic properties. This study aimed to determine the expression of PGRMC1 in fetal membranes among women with preterm labor (PTL), preterm premature rupture of membranes (PPROM), and acute histologic chorioamnionitis (HCA) during preterm birth.
Methods: Full thickness fetal membranes were obtained from women with gestational age-matched (32-34 weeks of gestational age), and categorized as PTL without HCA (PTL, n = 10), PPROM without HCA (PPROM, n = 10), PPROM with HCA (HCA, n = 10), and term without labor and HCA (term birth (TB), n = 9). The expression of PGRMC1 was assessed using western blot and Immunohistochemistry (IHC). As CD14 is a component of the innate immune system during inflammation, CD14 was used as inflammatory indicator. Nonparametric statistics were used for analysis.
Results: PGRMC1 expression for all of preterm birth was lower than in TB (P = 0.01). In HCA, PGRMC1 expression was significantly decreased compared to that in PTL and PPROM (P = 0.006. P = 0.001, respectively). PGRMC1 expression in PPROM was higher than that in PTL (P = 0.002). There was a negative correlation between PGRMC1 and CD 14/β-actin ratio (r = - 0.518; P = 0.002). IHC showed that PGRMC1 was predominant in the cytoplasm of cells, these results were consistent with those of the western blot analysis.
Conclusion: Preterm birth with PTL, PPROM, and especially HCA is associated with a decreased PGRMC1 in fetal membranes and inversely associated with increased CD 14.
Keywords: Chorioamnionitis; Fetal membranes; Preterm birth; Progesterone receptor membrane component 1.