Effect of Sublethal Prenatal Endotoxaemia on Murine Placental Transport Systems and Lipid Homeostasis.

Infection alters the expression of transporters that mediate the placental exchange of xenobiotics, lipids and cytokines. We hypothesized that lipopolysaccharide (LPS) modifies the expression of placental transport systems and lipid homeostasis. LPS (150 µg/kg; i.p.) treatments were administered for 4 h or 24 h, animals were euthanized at gestational days (GD) 15.5 or 18.5, and maternal blood, fetuses and placentae were collected. Increased rates of fetal demise were observed at GD15.5 following LPS treatment, whereas at GD18.5, high rates of early labour occurred and were associated with distinct proinflammatory responses. Lipopolysaccharide did not alter ATP-binding cassette (ABC) transporter mRNA expression but decreased fatty acid binding protein associated with plasma membrane (Fabppm) at GD15.5 (LPS-4 h) and increased fatty acid translocase (Fat/Cd36) mRNA at GD18.5 (LPS-4 h). At the protein level, breast cancer-related protein (Bcrp) and ABC sub-family G member 1 (Abcg1) levels were decreased in the placental labyrinth zone (Lz) at GD15.5, whereas P-glycoprotein (P-gp) and Bcrp Lz-immunostaining was decreased at GD18.5. In the placental junctional zone (Jz), P-gp, Bcrp and Abcg1 levels were higher at GD18.5. Specific maternal plasma and placental changes in triacylglycerol, free fatty acid, cholesterol, cholesterol ester and monoacylglycerol levels were detected in a gestational age-dependent manner. In conclusion, LPS-increased risk of fetal death and early labour were associated with altered placental ABC and lipid transporter expression and deranged maternal plasma and placental lipid homeostasis. These changes may potentially modify fetal xenobiotic exposure and placental lipid exchange in cases of bacterial infection.

Malaria in pregnancy regulates P-glycoprotein (P-gp/Abcb1a) and ABCA1 efflux transporters in the Mouse Visceral Yolk Sac.

Malaria in pregnancy (MiP) induces intrauterine growth restriction (IUGR) and preterm labour (PTL). However, its effects on yolk sac morphology and function are largely unexplored. We hypothesized that MiP modifies yolk sac morphology and efflux transport potential by modulating ABC efflux transporters. C57BL/6 mice injected with Plasmodium berghei ANKA (5 × 105 infected erythrocytes) at gestational day (GD) 13.5 were subjected to yolk sac membrane harvesting at GD 18.5 for histology, qPCR and immunohistochemistry. MiP did not alter the volumetric proportion of the yolk sac's histological components. However, it increased levels of Abcb1a mRNA (encoding P-glycoprotein) and macrophage migration inhibitory factor (Mif chemokine), while decreasing Abcg1 (P < 0.05); without altering Abca1, Abcb1b, Abcg2, Snat1, Snat2, interleukin (Il)-1ß and C-C Motif chemokine ligand 2 (Ccl2). Transcripts of Il-6, chemokine (C-X-C motif) ligand 1 (Cxcl1), Glut1 and Snat4 were not detectible. ABCA1, ABCG1, breast cancer resistance protein (BCRP) and P-gp were primarily immunolocalized to the cell membranes and cytoplasm of endodermic epithelium but also in the mesothelium and in the endothelium of mesodermic blood vessels. Intensity of P-gp labelling was stronger in both endodermic epithelium and mesothelium, whereas ABCA1 labelling increased in the endothelium of the mesodermic blood vessels. The presence of ABC transporters in the yolk sac wall suggests that this fetal membrane acts as an important protective gestational barrier. Changes in ABCA1 and P-gp in MiP may alter the biodistribution of toxic substances, xenobiotics, nutrients and immunological factors within the fetal compartment and participate in the pathogenesis of malaria-induced IUGR and PTL.

Vitamin D Receptor TaqI Polymorphism Is Associated With Reduced Follicle Number in Women Utilizing Assisted Reproductive Technologies.

PURPOSE: Calcitriol, or 1,25-hydroxycholecalciferol, is the active form of vitamin D. It binds and activates vitamin D receptor (VDR). Infertility and defective folliculogenesis have been observed in female vdr-knockout mice; however, whether VDR polymorphisms affect human ovarian responses to controlled ovarian stimulation (COS) remains unclear. We hypothesized that VDR polymorphisms are associated with infertility and COS responses. Thus, we evaluated the association between the TaqI, BsmI, and FokI VDR polymorphisms and ovarian responses in women undergoing COS. METHODS: In this study, we recruited a control group (n = 121) comprising volunteers with a history of natural conception and a second group of women undergoing COS (n = 70). TaqI, BsmI, and FokI genotyping was performed via restriction fragment length polymorphism analysis or TaqMan qPCR and Sanger sequencing. Intrafollicular 25(OH)D contents were measured in follicular fluid collected from COS patients during oocyte retrieval. Ovarian response parameters were obtained from patient medical records. RESULTS: There were no significant differences in the genotype frequencies of VDR polymorphisms (TaqI, BsmI and FokI) between the control and COS groups. However, the allele frequency of TaqI (C allele) was significantly lower in the COS group than in the control group (p = 0.02). Follicle number but not oocyte number was lower in patients with TaqI polymorphic (TC/CC) genotypes (p = 0.03). Importantly, the ratio between the number of follicles retrieved and intrafollicular estradiol concentrations was higher in patients with the TC/CC TaqI genotypes (p < 0.02). CONCLUSION: We identified an association between the VDR TaqI polymorphism and reduced follicle number in women undergoing COS, suggesting that VDR signaling affects the ovarian response to stimulation via unknown mechanisms.

Lower follicular fluid vitamin D concentration is related to a higher number of large ovarian follicles.

Vitamin D receptor-knockout mice fail to produce mature oocytes, indicating vitamin D is crucial for folliculogenesis in mice. However, the actions of vitamin D during folliculogenesis remain unknown. This prospective study aimed to assess whether follicular fluid (FF) vitamin D (25OHD3) concentrations are related to specific responses to ovarian stimulation. Women undergoing ovarian stimulation for IVF participated in the study. FF 25OHD3 concentrations were assessed in the first follicle aspirate on oocyte retrieval day. Oestradiol and progesterone concentrations were assessed on the trigger day. K-means grouping analysis showed that 25OHD3 FF concentrations clustered into a higher and lower group (mean ± SEM 17.4 ± 6.61 ng/ml and 35.5 ± 7.17 ng/ml, respectively, P < 0.001). The clusters were analysed according to the oestradiol and progesterone concentrations, follicle number and size and resulting oocyte number and maturity. The FF 25OHD3 concentrations were no different among the infertility diagnoses. The lower 25OHD3 group had more follicles (≥16.0 mm, P = 0.009) and higher serum oestradiol concentrations (P < 0.03) on the day of HCG administration. In this study, lower follicular 25OHD3 concentrations predicted a better response to ovarian stimulation shown by a greater production of larger follicles and higher serum oestradiol concentrations.