SRI Supplement to Reproductive Sciences - Volume 25 Number 1 - March 2018 - 155A

Scientific Abstracts

T-137
Matrix Metalloproteinase 15 Plays a Crucial Role in Human First
Trimester Trophoblast Invasion and is Not Regulated by Gestational
Age or Maternal Obesity. Alejandro Majali-Martinez,1 Carmen Tam
Amersdorfer,1 Juergen Pollheimer*,2 Denise Hoch†,1 Uwe Lang*,1 Nassim
Ghaffari Tabrizi-Wizsy*,1 Ursula Hiden*,1 Alexander Beristain*,3 Gernot
Desoye*,1 Martina Dieber-Rotheneder*.1 1Medical University of Graz,
Graz, Austria; 2Medical University of Vienna, Vienna, Austria; 3The
University of British Columbia, Vancouver, BC, Canada.
INTRODUCTION: Pregnancy complications such as preeclampsia and
maternal obesity have been linked with impaired trophoblast invasion
during the first trimester. Trophoblast invasion is mediated by matrix
metalloproteinases (MMPs). Here we hypothesized that MMP15, a novel
MMP highly expressed in human trophoblasts, is involved in trophoblast
migration and invasion and that MMP15 levels are decreased in obese
first trimester placentas.
METHODS: MMP15 localization in human first trimester placenta (week
7 to 12 of gestation) was assessed by immunofluorescence. MMP15
expression was knocked-down in first trimester chorionic villi explants.
Immunofluorescence for Ki67 and caspase-cleaved cytokeratin 18, as
well as trophoblast outgrowth were determined as a measurement of
trophoblast proliferation, apoptosis and migration/invasion, respectively.
MMP15 expression and protein levels were analysed by RT-qPCR and
Western blotting in lean (BMI=18.5-24.9) and obese (BMI≥30) placentas.
RESULTS: MMP15 co-localized with HLAG, a marker for invasive
extravillous trophoblast. MMP15 knock-down did not alter trophoblast
proliferation or apoptosis. However, decreased MMP15 expression
induced a down-regulation of trophoblast outgrowth (-43%, p<0.001;
MMP15-siRNA vs. non-targeting siRNA, respectively). Linear regression
analysis showed that BMI, gestational age or their interaction term were
not associated with MMP15 expression or protein levels (p>0.05).
CONCLUSION: MMP15 localizes to the invasive compartment of
the placenta; playing a pivotal role in trophoblast migration/invasion.
Unlike other MMP members, MMP15 levels are unaltered along the first

155A

trimester of pregnancy and are not regulated by obesity. Thus, this lack
of regulation might counteract the negative effect of maternal obesity in
trophoblast Invasion.

T-138
First Trimester Alcohol Exposure Alters Placental Perfusion and
Oxygenation Affecting Fetal Growth in a Non-Human Primate
Model. Jamie Lo,2 Matthias Schabel,2 Victoria Roberts,1 Chris Kroenke,2
Antonio Frias*.2 1ONPRC, Beaverton, OR, United States; 2Oregon Health
& Science University, Portland, OR, United States.
INTRODUCTION: Prenatal alcohol exposure impairs fetal growth and
stillbirth. The placenta likely contributes to these adverse outcomes, but
the specific vasoactive effects of alcohol linking placental perfusion and
oxygenation to impaired fetal growth are not known. We have developed
MRI techniques in non-human primate models to estimate placental
oxygen reserve (T2*) and perfusion using dynamic contrast enhanced
(DCE)-MRI. Our objective was to evaluate the adverse effects of first
trimester alcohol exposure on placental outcomes and fetal growth
longitudinally in-vivo.
METHODS: Timed-pregnant Rhesus macaques (n=24) were divided
into 2 groups: control (CON, n=12) and ethanol exposed (EE, n=12).
Animals were given either 1.5g/kg/day of ethanol (~ 6 drinks/day) or
an isocaloric control fluid from pre-conception until gestational day 60
(G60, term is G168). All underwent Doppler ultrasound (D-US) followed
by MRI procedures consisting of T2* and DCE measurements. D-US
was used to measure uterine artery (Uta) and umbilical vein velocimetry
and diameter to calculate Uta and placental volume blood flow (cQuta
and cQuv respectively). After imaging, animals underwent C-section
delivery for placenta collection and fetal necropsy at G85 (n=8), G110
(n=8) or G135 (n=8).
RESULTS: By D-US, cQuta and cQuv were decreased at G110 (p<0.05)
in EE vs. CON (Fig 1). Placental blood flow was reduced by DCE-MRI
at G85 (p=0.05) and G110 (p=0.02) in EE vs. CON (Fig 1). Distributions
of T2*throughout the placenta (Fig 2) show global reduction in T2* (and
hence blood oxyhemoglobin) in the EE vs CON at all time points. Fetal
biparietal diameter and weight were decreased at G110 (p=0.01) and G135
(p=0.02) in EE vs. CON (Fig 1).
CONCLUSION: Chronic first trimester ethanol exposure reduces
placental perfusion and oxygenation at early to mid-gestation, but impairs
fetal growth at mid to late-gestation. Slight improvement of placental
function by late-gestation suggests that placental adaptation to early
perturbations allows for compensated placental function, but cannot
maintain normal growth.
*Figure(s) will be available online.

T-139
Pravastatin Induces Heme Oxygenase Activity and Enhances
Placental Development in a Murine Model. Abraham Tsur†, Flora
Kalish, Jordan Burgess†, Hui Zhao, Kerriann M Casey, Maurice L
Druzin*, Ronald J Wong*, David K Stevenson*. Stanford University
School of Medicine, Stanford, CA, United States.
INTRODUCTION: Pravastatin is currently being studied clinically for
the prevention of preeclampsia. Low expression of heme oxygenase-1
(HO-1) due to polymorphisms in the human HO-1 promoter region may
cause impaired placental development resulting in intrauterine growth
restriction (IUGR), preeclampsia, and recurrent miscarriages. We have
shown that pregnant HO-1 heterozygous (HO-1+/-, Het) mice have
abnormal placental development, with thinner spongiotrophoblast layers
and increased Sflt-1 levels (Zhao H. et al., 2009). We have also found that
statins can induce HO-1 expression. Therefore, our aim was to evaluate
the effect of pravastatin on pregnancy outcome and placental development
in HO-1-deficient mice.
METHODS: We compared untreated Het mice (control, n=9) with Het
mice treated with pravastatin (10 mg/g/d; n=14) added to their drinking
water 1 wk prior to timed-pregnancy breeding, for a total of 3.5 wks. At
E14.5, dams were sacrificed, litter sizes recorded, and livers and placentas

Thursday Posters

late term (65d) gestation, weighed, and the labyrinth of placentas frozen in
liquid N2 and stored at -80C until assayed. Mitochondria were isolated and
mito density (mitoDNA/nuclearDNA ratio by qPCR), protein expression
(Western blot analysis) of both respiratory chain Complexes (CI-V) and
3-nitrotyrosine of CI/CIV, and CI/IV enzyme activities were measured
in NMX/HPX male and female placentas.
RESULTS: At late but not midterm gestation, HPX decreased (P<0.05)
male and female fetal body wts (FBW) by 32 and 35%, respectively,
had no effect on placenta wt, and increased (P<0.05) placenta wt/FBW
ratios. In males, HPX decreased mito density and CI (NMX: 0.62±0.08;
HPX: 0.30±0.11 specific activity units) and CIV (NMX 0.20±0.01, HPX:
0.15±0.01) enzyme activities at late but not midterm gestation. HPX
increased (P<0.01) 3-nitrotyrosine expression of CI and CIV proteins
more than 2 fold from NMX in both male and female placentas at late but
not midterm gestation. Unexpectedly, HPX increased (P<0.05 for each
Complex protein) expression of CI, II, III and V at midterm and only
CIV at late term in male placentas compared to their age-matched NMX
controls. In female placentas, HPX had no effect on mito density, CI/CIV
activities, or protein expression of any of the respiratory chain Complexes
(CI-CV) at either mid or late gestation. Lastly, independent of hypoxia and
sex, advancing gestation from mid to late term decreased (P<0.05 for each
protein) the expression of Complexes (CI-V) and VDAC, an outer mito
membrane protein, by an average of 25-43% depending on the protein.
CONCLUSION: HPX decreases indices of mito respiration of male
placentas while female placentas are protected. The compensatory increase
of protein expression of respiratory complexes to HPX in mid gestation
is not sustained in late gestation, indicating an inhibitory effect on mito
function in male placentas with prolonged exposure. We conclude that
HPX decreases mito function in the placenta in a sex- and gestationaldependent manner, identifying a sexual dimorphism in the vulnerability
of placentas to HPX. NIH RO1HL 126859 LPT.

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
