Biology subjects

Troja, W.

Publications and source records attributed to Troja, W..

3 recordsLinked to original sources

bioRxiv2020

Insulin-like growth factor 1 signaling in the placenta requires endothelial nitric oxide synthase to support trophoblast function and normal fetal growth

Currently, there is no effective treatment for placenta dysfunction in utero. In a ligated mouse model of fetal growth restriction (FGR), nanoparticle-mediated human insulin-like 1 growth factor (hIGF1) gene delivery (NP-Plac1-hIGF1) increased hIGF1 expression and maintained fetal growth. However, whether it can restore fetal growth remains to be determined. Using the endothelial nitric oxide synthase knockout (eNOS-/-) mouse model, a genetic model of FGR, we found that despite inducing expression of hIGF1 in the placentas treated with NP-Plac1-hIGF1 (P=0.0425), FGR did not resolve. This was associated with no change to the number of fetal capillaries in the placenta labyrinth; an outcome increased with NP-Plac1-hIGF1 treatment in the ligated mouse model, despite increased expression of angiopoietin 1 (P=0.05) and suggested IGF1 signaling in the placenta requires eNOS to modulate placenta angiogenesis. To further assess this hypothesis, we used the BeWo Choriocarcinoma cell line and human placenta explant cultures that were treated with NP-Plac1-hIGF1, oxidative stress was induced with hydrogen peroxide (H2O2) and NOS activity inhibited using the inhibitor L-NMMA. In both BeWo and explants, the protective effect of NP-Plac1-hIGF1 treatment against H2O2 induced cell death/lactate dehydrogenase release was prevented by eNOS inhibition (P=0.003 and P<0.0001, respectively). This was associated with an increase in mRNA expression of oxidative stress markers HIF1 (P<0.0001) and ADAM10 (P=0.0002) in the NP-Plac1-hIGF1+H2O2+L-NMMA treated BeWo cells. These findings show for the first time the requirement of eNOS/NOS in IGF1 signaling in placenta cells that may have implications for placental angiogenesis and fetal growth.

physiology↗

bioRxiv2020

Placental and fetal characteristics of the Ohia mouse line recapitulate outcomes in human hypoplastic left heart syndrome

Congenital heart defects (CHDs) are the most common birth defect worldwide. The morbidity and mortality associated with these defects is compounded by increased frequency of fetal growth abnormalities. In the Ohia mouse model of hypoplastic left heart syndrome (HLHS), the double homozygous genotype is embryonically lethal at mid-pregnancy; a time in which optimal establishment of the placenta is crucial to fetal survival. We aimed to characterize placental and fetal growth and development in the double heterozygous genotype (Sap130m/+Pcdha9m/+) to determine whether the genetic mutations associated with HLHS in the Ohia mouse also affect the placenta. The frequency of fetuses with reduced weight near term was shifted in the Sap130m/+Pcdha9m/+ fetuses compared to wildtype. This shift in fetal weight distribution in the Sap130m/+Pcdha9m/+ fetuses was associated with reduced labyrinth region area (P<0.001) and reduced fetal capillary density (P<0.001) in the placentas. Positive correlations were observed between fetal weight and placenta mRNA expression of several nutrient transporters in the Sap130m/+Pcdha9m/+ fetuses but not observed in the wildtype. Increased protein expression of Slc7a5 (P<0.05) and Slc7a8 (P<0.05) was also found in the placenta of Sap130m/+Pcdha9m/+ fetuses. This data shows, despite a potential compensatory mechanism to increase nutrient transport, abhorrent placental vascularization leads to inadequate fetal growth in the Ohia mouse model. Such differences are similar to findings in studies of human placentas and highlights the importance of this mouse model in continuing to understand the developmental links and disruptions to the heart-placenta axis.

physiology↗

bioRxiv2018

Abnormalities of placental development and function are associated with the different fetal growth patterns of hypoplastic left heart syndrome and transposition of the great arteries.

BackgroundBirthweight is a critical predictor of congenital heart disease (CHD) surgical outcomes. Hypoplastic left heart syndrome (HLHS) is cyanotic CHD with known fetal growth restriction and placental abnormalities. Transposition of the great arteries (TGA) is cyanotic CHD with normal fetal growth. Comparison of the placenta in these diagnoses may provide insights on the fetal growth abnormality of CHD.\n\nMethodsClinical data and placental histology from placentas associated with Transposition of the Great Arteries (TGA) were analyzed for gross pathology, morphology, maturity and vascularity and compared to both control and previously analyzed HLHS placentas [1]. RNA was isolated from HLHS, TGA and control placentas and sequenced by Illumina HiSeq.Gene, analysis was performed using TopHat, R and MSigDB. Cluster analysis was performed using GoElite and Pathway analysis performed using PANTHERdb Overrepresentation Test. Immunohistochemistry was utilized to assess placental nutrient transporter expression in all three groups.\n\nResultsPlacental weight was reduced in TGA cases, and demonstrated reduced villous vasculature, immature terminal villi, and increased fibrin deposition in the parenchyma compared to controls and reflected our previous data from HLHS placentas. However, birth weight was not reduced in TGA cases compared to controls in contrast to the HLHS cohort and birthweight:placental weight ratio was significantly increased in TGA cases but not HLHS compared to control. Need to include RNA and IHC.\n\nConclusionsDespite common vascular disturbances in placentas from HLHAs and TGA, these do not account for the

physiology↗