Senescence associated with inflammation in chorioamniotic membranes of pregnancies complicated by PPROM and PTL

Abstract

Preterm Premature Rupture of Membranes (PPROM) and Preterm Labor (PTL) with intact membranes are one of the main problems in Obstetrics. Although many risk factors are shared between these unfavorable gestational outcomes and present overlapping mechanisms, is suggested that PPROM and PTL have a singular inflammatory and oxidative signature. Oxidative stress-induced senescence in fetal membranes is an important mechanism that culminates in PPROM. Senescence is characterized by an inflammatory signature named Senescence Associated Secretory Phenotype (SASP). Objective: To characterize ²Galactosidase and SASP markers expression in chorioamnionitis membranes of pregnancies complicated by PPROM and PTL. Patients and Methods: This is a cross-sectional study that will consist of 60 fragments of chorioamnionitis membranes, with 30 membranes from pregnancies complicated by PPROM and 30 from pregnancies complicated by PTL, which evolves to preterm birth. Sociodemographic and obstetrics data will be collected through the analysis of electronic patient records. In the moment of pregnancy resolution, fragments of the chorioamnionitis membranes will be removed and immediately frozen in liquid nitrogen and stored at -80° C until the moment of processing. Other fragments of chorioamnionitis membranes will be fixed in 10% formalin, embedded in paraffin, and subjected to histopathological analysis to assess the presence of histological chorioamnionitis. Senescence analysis by ²-Galactosidase (Senescence-Associated ²-Galactosidase - SA-²Gal) will be performed using the Senescence Detection kit, Abcam, Cambridge, UK). Enzyme-linked immunosorbent assay (ELISA) will be used to quantify SASP markers, Interleukin (IL) 1 ², IL-6, IL-8 and IL-13, and Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) in fetal membrane fragments. Pregnant women with chronic diseases such as arterial hypertension, nephropathy, collagenosis, and diabetes mellitus, as well as those with gestational diabetes mellitus, pre-eclampsia, isthmocervical incompetence, placental abruption, placenta previa, oligoamnios, polyhydramnios, congenital malformation, HIV and death intrauterine were not included in the study. All pregnant women will sign the Informed Consent Term after the project has been approved by the CEP. The data will be analyzed considering the statistical assumptions and the significance level adopted will be 5%.(AU)