SRI Supplement to Reproductive Sciences - Volume 25 Number 1 - March 2018 - 71A

Scientific Abstracts

O-043
Reduced Retinoic Acid in Preeclamptic Decidua. Augustine
Rajakumar,1 Martina Badell,1 Maureen Kane,2 Hongyan Qu,1 Robert N
Taylor,3 Neil Sidell*.1 1Emory University School of Medicine, Atlanta, GA,
United States; 2University of Maryland, Baltimore, MD, United States;
3
Wake Forest School of Medicine, Winston-Salem, NC, United States.
INTRODUCTION: While the role of placenta in preeclampsia (PE) has
been extensively studied, contributions from the maternal (decidual) side
of the fetomaternal interface have received less attention. One line of study
proposes that an imbalance of certain decidual immune cells can contribute
to PE by causing a hypervigilant maternal immune response. Based on our
understanding of the role of retinoic acid (RA) in maintaining immune
tolerance in GI tissue and its reduced production in certain inflammatory
bowel diseases (e.g. Crohn's), we posited the possibility that the hyperinflammatory state occurring with PE may be associated with suppressed
RA levels in the decidua.
METHODS: Decidua tissues were obtained from 9 healthy (NP-D) and
10 PE (PE-D) term placentas and evaluated for RA levels by LC-MS/
MS. Decidual mononuclear cells were isolated by enzyme digestion
and density gradient centrifugation. To determine the cellular sources
of RA, we utilized an Aldefluor assay to quantify retinal dehydrogenase
(RALDH), the rate-limiting enzyme in the synthesis of RA from retinol.
Subsequently, the cells were stained with specific antibodies to determine
their lineage and analyzed by multicolor flow cytometry. FACS was used
to isolate subpopulations producing high levels of RALDH. RA synthesis
was quantified in separated cell populations by LC-MS/MS following the
addition of retinol in 6 hr cultures.
RESULTS: RA levels (pmol/g protein) in PE-D was significantly
lower than that in NP-D (180±32 vs 247±33; p=0.0003). Macrophages/
monocytes (CD14+ cells) showed >6-fold higher RALDH activity
than that found in stromal cells (CD10+), T-cells (CD3+), or dendrites
(CD11c+). The highest RALDH activity was found in the subpopulation
of anti-inflammatory macrophages (M2 macrophages) delineated by
the simultaneous expression of CD14 and CD163. The greater RA
synthesizing capacity of M2 versus CD14+CD163neg (M1) cells was
confirmed by direct quantitation of RA synthesis from retinol.
CONCLUSION: The reduced levels of RA in PE-D suggests that a defect
in RA biosynthesis may play a role in the maternal hyper-inflammatory
response associated with PE. The major RA-producing cells in term
decidua are M2 suppressor monocyte/macrophages. Interestingly, the
frequency of decidual M2 cells has been shown to be reduced in PE
compared with normal pregnancies. Together, our findings suggest that
reduced RA production via defects in M2 cell number or function may
contribute to the pathophysiology of PE.

O-044
Placental Uric Acid Transport System and Its Impact on Fetal
Development. Benjamin P Lüscher,1 Philipp Schneider,1 Daniel Surbek,2
Marc U Baumann.2 1University of Bern, Bern, Switzerland; 2Women's
Health University Hospital, Bern, Switzerland.
INTRODUCTION: Uric acid is increased in women with pre-eclampsia,
a pregnancy-specific disease characterized by hypertension and
proteinuria, and is believed to play a significant role in its pathogenesis.

71A

Hyperuricemia originates from renal and placental dysregulation of uric
acid transport and may lead to long-term maternal cardiovascular risk
and alterations in fetal programming. The placental uric acid transport
system and its regulation are largely unknown. Studies using the BeWo
choriocarcinoma cell line have indicated a para-cellular pathway for uric
acid transport. The main uric acid transporter in the placenta is glucose
transporter (GLUT)-9. In these studies we use the GLUT9-knock out
mouse model to investigate the placental uric acid system and its impact
on fetal development. We hypothesized that fetal mice with lack of
placental GLUT9 will show hyperuricemia, abnormal organ development
and altered growth pattern after birth.
METHODS: Female GLUT9(+/-) mice were mated with GLUT9(+/-) male
mice. At gestational day 18.5 fetuses were sacrificed for blood sampling
and measurement of uric acid serum levels, while in other pregnancies
following birth the pups were daily weighted until day 70. At day 70 these
mice were sacrificed and pancreas, liver and kidney were weighted and
processed for histological analysis to assess potential abnormal organ
development.
RESULTS: The GLUT9(-/-) fetuses showed a 3-fold increase in serum
uric acid levels compared to GLUT9(+/-) and GLUT9(+/+) fetuses and their
GLUT9(+/-) mothers. GLUT9(-/-) mice showed neonatal growth restriction
compared to GLUT9(+/-) and GLUT9(+/+) mice. GLUT9(-/-) mice had
decreased kidney mass by 25±0.15% (mean±SD, n=7, p<.01, Student's
t-test) and 35±0.21% (n=7, p<.01) for the left and the right kidney,
respectively, compared to GLUT9(+/-) mice.
CONCLUSION: These data show for the first time that in vivo uric acid
is not transported across the placenta by a para-cellular pathway, but is
dependent on a specific uric acid transporter. Moreover our data indicate
that GLUT9 is the main uric acid transporter in the placenta. Further
there is strong evidence that fetal hyperuricemia is responsible for the
observed impaired development of neonatal GLUT9(-/-) mice. Further
studies investigating the potential links between hyperuricemia, altered
placental function and metabolic fetal programming are eagerly needed.

O-045
Molecular Control of Steroid Hormone Production via PostTranscriptional Regulation of the Steroidogenic Acute Regulatory
Protein by the lncRNA H19. Yong Chen,1 Chunrong Qin,2 Xia Xi,3
Amanda N Kallen*.4 1School of Basic Medical Sciences, Fujian Medical
University, Fuzhou, China; 2Shenzen Maternity and Child Health Institute,
Shenzhen, China; 3Shenzhen Hospital, Guangdong Province, China; 4Yale
School of Medicine, New Haven, CT, United States.
INTRODUCTION: Steroid hormones have broad physiologic roles
and are essential for human reproduction. Synthesis of steroid hormones
requires a transport protein known as the steroidogenic acute regulatory
protein (Star). We recently showed that Star mRNA is regulated at the
posttranscriptional level by the long noncoding RNAs (lncRNA) H19 via
sequestration of the microRNA let-7, which binds and antagonizes Star.
Our objective was to determine whether this novel regulatory mechanism
functions in vivo, and if so, what proportion of steroids produced result
from lncRNA regulation.
METHODS: We utilized an H19 knockout (H19KO) mouse to investigate
the role of H19 in STAR protein and progesterone (P) production. H19KO
and wild type (WT) mice at each mouse estrus stage (proestrus [P], estrus
[E], metestrus [M], and diestrus [D]) were euthanized, blood samples
collected, and ovaries removed (n=3 for WT and H19KO at each estrus
stage). Western blot for STAR and quantification of P using ELISA was
performed. Litter sizes were compared in H19KO and WT mice between
8-12 weeks of age (n=10 per group). Data were analyzed using one-way
ANOVA; p values <0.05 were considered significant.
RESULTS: In WT mice, ovarian STAR peaked immediately after
ovulation occurred (in metestrus, as expected) (Fig.1a). Moreover, P levels
were highest during metestrus in WT mice, correlating with peak STAR
production (Fig. 1b). However, in H19KO mice, STAR was highest in
the estrous phase (preovulation) (Fig.1a). Moreover, the overall P pattern
was also markedly different in H19 KO mice (Fig.1b): while WT mice
demonstrated a distinct P "peak" of nearly 7,000 pg/mL, H19KO mice

Thursday Orals

RESULTS: We included 342 cases and 210 controls in our analysis. FMD
did not differ between groups and remained unaltered over time. NG
induced dilation decreased (B -0.073 % per year; p 0.013) and brachial
artery diameter (B 0.014 % per year; p<0.001) increased over time in
both groups. However, when corrected for cofounders that are known to
affect endothelial function (smoking, vitamin use, use of anti-hypertensive
drugs, glucose and postmenopausal state), the gradual enlargement in
vessel diameter over time remained (B 0.012 % per year; p < 0.001).
CONCLUSION: Independent of obstetric history endothelial dependent
dilation did not change while endothelial independent (NG induced)
dilation decreased with aging. This age related stiffening of the vasculature
was comparable in women with and without vascular complicated
pregnancy and related to classical cardiovascular risk factors and arterial
vessel enlargement.

Reproductive Sciences Vol. 25, Supplement 1, March 2018

Table of Contents for the Digital Edition of SRI Supplement to Reproductive Sciences - Volume 25 Number 1 - March 2018