Gene expression profile in labouring and non-labouring human placenta near term

Abstract

The duration of pregnancy and initiation of labour are thought to be controlled by fetal, maternal and placental factors. The aim of this study was to investigate whether labour influences gene expression in placenta near term. Placental samples were obtained from 27 women after vaginal delivery (labouring) and 17 women after elective Caesarean section (non-labouring). All women were Caucasian and had uncomplicated pregnancies. For global gene expression analysis, 17 human oligo-arrays were used, representing 24 650 genes each. An empirical Bayes analysis was applied in order to find differentially expressed genes. About 8000 genes that were represented on the arrays met our quality criteria. Ninety two genes were down-regulated and 94 genes were up-regulated in labouring placentas compared to non-labouring placentas. However, none of these was differentially expressed at a significant level (>2.5-fold change and a P-value of <0.01). We conclude that gene expression in near term human placenta is not significantly altered by labour.

Decreased placental expression of hPGH, IGF-I and IGFBP-1 in pregnancies complicated by fetal growth restriction

“…No differences have previously been found in the concentration of hPGH in the maternal blood and the amniotic fluid in respect to caesarean section or vaginal delivery [53,54]. Despite the lack of data regarding the particular genes of this study, it has been shown that gene expression in a near term placenta is not significantly altered by labor, suggesting that the mode of delivery has no major implication in the interpretation of results of genomic studies on placenta [55].…”

The effects of labor on differential gene expression in parturient women, placentas, and fetuses at term pregnancy

“…In placental tissues, labor increases the expression of genes involved in placental oxidative stress, inflammatory cytokines, angiogenic regulators, and apoptosis [31], and regulates the genes involved in placental hormone metabolism [23,32]. Similar to previous studies, we found that the genes upregulated in placenta by labor were involved in angiogenic regulators, immune response, inflammatory response, and apoptosis.…”

“…Functional genomics of parturition had been studied in several different species, including mice [17], rats [20], sheep [25], and humans [26]. Previous studies have focused on the effects of labor on differential gene expression profiles with genome-wide studies of different human tissues, including the myometrium [19,21,26e29]; various parts of uterus in the same pregnant women (uterine fundus, lower segment, and cervix) [18]; chorioamniotic membranes [22,30]; MB [22]; and placenta [23,31]. Overall, the genes involved in immune pathways, inflammatory processes, hormones, and components of the extracellular matrix have been found to be very important during labor because of their differentially expressed gene levels.…”

Perfusion of human placenta with hemoglobin introduces preeclampsia-like injuries that are prevented by α1-microglobulin

“…Recently, it was shown that labor initiates oxidative stress which, depending on length and intensity, varies with the lowest degree of stress found in placental tissue from elective cesarean section [41]. As far as the gene profile is concerned, there apparently is no unanimous opinion [42]. Oxidative stress related changes in placental tissue is a typical hallmark of PE [3].…”