SRI Supplement to Reproductive Sciences - Volume 25 Number 1 - March 2018 - 80A

80A

Reproductive Sciences Vol. 25, Supplement 1, March 2018

and StAR) and fibrosis in lesions as compared with the AL group. CR
also attenuated IGF-1 and PI3K/mTOR/Akt signaling, but activated the
SIRT1 and AMPK signaling pathways.
CONCLUSION: CR, instituted either before or after the induction of
endometriosis, dramatically curbs the growth of endometriotic lesions
and fibrogenesis likely through multiple mechanisms. The dramatic
reduction in lesion weight as a result of CR suggests that cellular sensors
of energy availability and their downstream signaling pathways should
play important roles in estrogen production, angiogenesis, proliferation,
autophagy and fibrogenesis. In addition, CR and CR mimetic, even when
instituted well after lesions are established, may stall the development of
endometriosis. Thus, this study provides a novel perspective on autophagy
and its connection with SIRT1, IGF-1, and, in particular, AMPK. Given
the scarcity in research on how lifestyle can impact on the development
of endometriosis, our study should hopefully stimulate more research
in this area.

O-069
miR-451a-c-MYC Pathway Regulation of 60S Acidic Ribosomal
Protein P1 (RPLP1) Expression: A Novel Pathway in Endometriotic
Lesion Tissue Survival. Zahraa Alali†,2 Tommaso Falcone,1 Warren B
Nothnick*.2 1Cleveland Clinic, Cleveland, OH, United States; 2University
of Kansas Medical Center, Kansas City, KS, United States.
INTRODUCTION: Endometriosis is a common disease in women of
reproductive age in which endometrial tissue establishes and survives
in ectopic locations, yet the mechanisms that drive lesion survival are
poorly understood. We have previously identified RPLP1 as a novel
factor that modulates endometriotic epithelial cell survival. RPLP1 has
been identified as a c-MYC responsive gene in rat fibroblast (Guo et al.,
2000), but a similar pathway has not been established in endometriotic
lesion tissue/cells. The objective of the current study was to examine
the role of c-MYC in regulating RPLP1 expression in endometriotic
lesion tissue and epithelial cells to decipher the role of this protein in
endometriosis pathophysiology.
METHODS: c-MYC and RPLP1 mRNA were assessed using qRT-PCR
in paired endometriotic lesion tissue and eutopic endometrium (N=77
lesions and N=55 eutopic). RPLP1 regulation by c-MYC and cell survival
were assessed in vitro using the endometriotic epithelial cell line, 12Z.
RESULTS: Average expression level of lesion c-MYC mRNA was
significantly greater compared to paired eutopic endometrium (4.1 fold
increase; P<0.01). Lesion c-MYC mRNA levels were positively and
significantly correlated with those of RPLP1 (Pearson r = 0.56; P<0.01). To
evaluate if c-MYC modulated 12Z cell RPLP1 expression, 12Z cells were
transfected with c-MYC siRNA and RPLP1 mRNA and protein expression
were examined. Forced expression of c-MYC siRNA significantly
suppressed c-MYC expression as well as that of RPLP1 (P<0.05; N=4).
As miR-451a putatively regulates both c-MYC and RPLP1, we examined
if it could modulate their expression. Compared to non-targeting miRNAtransfected 12Z cells, forced expression of miR-451a significantly reduced
both c-MYC mRNA and protein expression as well as that of RPLP1
(P<0.01; N=4) which was associated with reduced cell survival.
CONCLUSION: The average level of expression for both RPLP1 and
c-MYC are significantly elevated in endometriotic lesion tissue and
display a positive correlation. Further, c-MYC regulation of RPLP1
expression involves post-transcriptional regulation by miR-451a. Our
observations continue to support our notion that miR-451a expression
modulates endometriotic lesion survival and this regulatory pathway
includes RPLP1 and c-MYC.

O-070
Prostaglandin E2 Signaling and Epigenetic Regulation of Proapoptotic
miRNA15a in Endometriosis. Joe A Arosh*,1 Jone A Stanley,1 Kaylon
Bruner-Tran,2 Kevin K Osteen,2 Sakhila K Banu.1 1Texas A&M University,
College Station, TX, United States; 2Vanderbilt University School of
Medicine, Nashville, TN, United States.
INTRODUCTION: Epigenetics plays an important role in the
pathogenesis of endometriosis. Recent multi-omics studies indicate that
epigenetic silencing of proapoptotic genes and miRNAs is one of the

Scientific Abstracts

important contributing factors in the survival of chronic inflammatory
diseases. In the present study, we investigated the interaction between
proinflammatory mediator prostaglandin E2 (PGE2) signaling and
epigenetic silencing, restoration, and proapoptotic role of miRNA15a
in endometriosis.
METHODS: Peritoneal endometriotic lesions from women with
endometriosis (n=6) and endometrial biopsy from age-matched
endometriosis-free women (n=6) were obtained during the proliferative
phase of the menstrual cycle. Human endometriotic epithelial cells 12Z
and stromal cells 22B cells (n=4) and 12Z/22B-xenograft mice (n=12)
were used as in vitro and in vivo models. Expression and regulation of
miR15a was determined by array, qPCR, MS-PCR, bisulphite sequencing,
and ChiP-PCR.
RESULTS: Expression of miR15a is barely detectable (p<0.05) in the
peritoneal endometriotic lesions compared to endometrium in women,
which is due to partial DNA methylation. Pharmacological inhibition of
PGE2 receptors EP2 and EP4 increases (p<0.05) the expression of miR15a
in 12Z and 22B cells in vitro and experimental endometriosis in vivo.
Inhibition of EP2/EP4 decreases (p<0.05) enrichment of DNMT3a/3b,
MeCP-2, Sin3A, MAD1, and coREST1 proteins; decreases (p<0.05) the
enrichment of H3K9me3, H3K27me3, EZH2 and SUV39H1 proteins; and
does not change the enrichment of H3K4me3, H3K9ac, H3K27ac, and
POL II in the promoter region of miR15a in 12Z and 22B cells. Restoration
of miR15a by overexpression induces (p<0.05) apoptosis of 12Z and 22B
cells in vitro. Intraperitoneal administration of miRNA15a mimics induces
(p<0.05) apoptosis of lesions in experimental endometriosis in vivo.
CONCLUSION: Our new findings suggest that expression of
proapoptotic miRNA15a is epigenetically silenced in the endometriotic
lesions and inhibition of PGE2-EP2/EP4 signaling restores its expression
by modulating DNA methylation and H3 Histone methylation. Restoration
of miRNA15a induces apoptosis of endometriotic cells and lesions, and
therefore, targeting proapoptotic miRNA15a could emerge as potential
non-steroidal and apoptosis-targeted therapy for endometriosis.

O-071
Low Intensity Physical Activity May Protect against Spontaneous
Preterm Labor through IL10 Pathways. Valerie Steckle†,1,2 Oksana
Shynlova*,1,2 Ryan Seeto†,1 Sheryl Hewko†,1 Alan Bocking*,1,2 Stephen
Lye*.1,2 1Sinai Health System, Toronto, ON, Canada; 2University of
Toronto, Toronto, ON, Canada.
INTRODUCTION: The maternal immune system is a key regulator in
the timely onset of parturition. Although studies have shown that low
intensity physical activity induces long-term anti-inflammatory immune
responses in the general population, exercise studies in pregnant women
have been largely inconclusive because the intensity of physical activity
has not been considered. We hypothesized that low intensity exercise
protects pregnant women from spontaneous preterm labor (SPTL, delivery
<37 weeks gestational age) by inducing anti-inflammatory immune
responses. Our study aimed to assess the value of maternal cytokines as
predictive biomarkers of SPTL in asymptomatic pregnant women, while
also elucidating the effects of antenatal exercise on the immune system.
METHODS: Data was collected through the Ontario Birth Study cohort
at Mount Sinai Hospital, Toronto. Of 1375 participants, 28 women with
singleton pregnancies who completed the exercise questionnaires and gave
blood samples at 16- and 27-weeks GA experienced SPTL. This group
was compared to 52 healthy pregnant women who delivered at term (≥37
weeks GA). Subjects were matched for age and parity. Concentrations of
19 cytokines in maternal plasma were measured using Luminex assays
(BioRad). Physical activity patterns were assessed using the validated
International Physical Activity Questionnaire (IPAQ). Cytokine and
exercise data were analyzed using Mann-Whitney and Spearman
correlation tests, p<0.05 was considered significant.
RESULTS: There was no significant difference in the exercise patterns of
SPTL women and controls, although SPTL women tended to report less
walking than controls (897±651 MET-minutes versus 1380±1495 METminutes per week). We observed a significantly increased concentration
of IL10 in SPTL subjects at both 16 and 27 weeks, as well as significantly

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