Expression of Stress-Mediating Genes is Increased in Term Placentas of Women with Chronic Self-Perceived Anxiety and Depression

Abstract

Anxiety, chronical stress, and depression during pregnancy are considered to affect the offspring, presumably through placental dysregulation. We have studied the term placentae of pregnancies clinically monitored with the Beck's Anxiety Inventory (BAI) and Edinburgh Postnatal Depression Scale (EPDS). A cutoff threshold for BAI/EPDS of 10 classed patients into an Index group (>10, n = 23) and a Control group (<10, n = 23). Cortisol concentrations in hair (HCC) were periodically monitored throughout pregnancy and delivery. Expression differences of main glucocorticoid pathway genes, i.e., corticotropin-releasing hormone (CRH), 11β-hydroxysteroid dehydrogenase (HSD11B2), glucocorticoid receptor (NR3C1), as well as other key stress biomarkers (Arginine Vasopressin, AVP and O-GlcNAc transferase, OGT) were explored in medial placentae using real-time qPCR and Western blotting. Moreover, gene expression changes were considered for their association with HCC, offspring, gender, and birthweight. A significant dysregulation of gene expression for CRH, AVP, and HSD11B2 genes was seen in the Index group, compared to controls, while OGT and NR3C1 expression remained similar between groups. Placental gene expression of the stress-modulating enzyme 11β-hydroxysteroid dehydrogenase (HSD11B2) was related to both hair cortisol levels (Rho = 0.54; p < 0.01) and the sex of the newborn in pregnancies perceived as stressful (Index, p < 0.05). Gene expression of CRH correlated with both AVP (Rho = 0.79; p < 0.001) and HSD11B2 (Rho = 0.45; p < 0.03), and also between AVP with both HSD11B2 (Rho = 0.6; p < 0.005) and NR3C1 (Rho = 0.56; p < 0.03) in the Control group but not in the Index group; suggesting a possible loss of interaction in the mechanisms of action of these genes under stress circumstances during pregnancy.

Keywords: RT-qPCR; antenatal stress; hair cortisol; human; term-placentae.

Figure 1

(A) Heat map plot of gene expression data of term-placenta samples of patients indicating symptoms of depression and anxiety (Index; n = 23) and patients with no symptoms of depression or anxiety (Control, n = 23). Both rows and columns are clustered using correlation distance and average linkage. Colors represent mRNA levels (red: higher, green: lower). (B) Principal component analysis (PCA) plot of gene expression data of male and female term-placenta samples of patients indicating symptoms of depression and anxiety (Index; n = 23) and patients with no symptoms of depression or anxiety (Control, n = 23). SVD (singular value decomposition) with imputation is used to calculate principal components. X and Y axis shows principal component 1 and principal component 2 that explain 41.5% and 26.8% of the total variance, respectively.

Figure 2

Differential gene expression of stress-related genes (Arginine Vasopressin—AVP; corticotropin-releasing hormone—CRH; 11β-hydroxysteroid dehydrogenase—HSD11B2; O-GlcNAc transferase—OGT; glucocorticoid receptor—NR3C1) in term-placenta samples of patients indicating symptoms of depression and anxiety (Index) and patients with no symptoms of depression or anxiety. The gene names are indicated on the X axis and the value on the Y axis represents the gene expression level in the binary logarithm (log 2) value. Data are presented by violin plot showing median and inter-quartile range (Q1–Q3). Asterisks indicate significant differences among groups (* p < 0.05; *** p < 0.001).

Figure 3

Western blot (WB) detection of the corticotropin-releasing hormone (CRH) and Arginine Vasopressin (AVP) proteins in term-placentas of patients indicating symptoms of depression and anxiety (Index) and patients with no symptoms of depression or anxiety (Control). (A) Human anti-CRH polyclonal antibody (LS-B11889) tested in Index and Control group and (B) between males and females identified expected bands at 22 kDa. In (C) the human anti-AVP polyclonal antibody (MBS9205129) tested in Index and Control groups identified expected bands at 17 kDA. (D) Graphical representation of protein expression of CRH and AVP between Index and Control groups.

Figure 4

Differential gene expression of stress-related genes (A: corticotropin-releasing hormone—CRH; B: Arginine Vasopressin—AVP; C: 11β-hydroxysteroid dehydrogenase—HSD11B2; D: glucocorticoid receptor—NR3C1; E: O-GlcNAc transferase—OGT) in male and female term-placentas of patients indicating symptoms of depression and anxiety (Index) and all patients examined. Asterisks indicate significant differences among groups (* p < 0.05).