Extracellular vesicles-coupled miRNAs from oviduct and uterus modulate signaling pathways related to lipid metabolism and bovine early embryo development

BACKGROUND

Extracellular vesicles (EVs) present in oviductal (OF) and uterine fluid (UF) have been shown to enhance bovine embryo quality during in vitro culture by reducing lipid contents and modulating lipid metabolism-related genes (LMGs), while also influencing cell proliferation, suggesting their involvement on the regulation of different biological pathways. The regulation of signaling pathways related to cell differentiation, proliferation, and metabolism is crucial for early embryo development and can determine the success or failure of the pregnancy. Bioactive molecules within EVs in maternal reproductive fluids, such as microRNAs (miRNAs), may contribute to this regulatory process as they modulate gene expression through post-transcriptional mechanisms.

RESULTS

From the 20 differentially expressed miRNAs, 19 up-regulated in UF-EVs (bta-miR-134, bta-miR-151-3p, bta-miR-155, bta-miR-188, bta-miR-181b, bta-miR-181d, bta-miR-224, bta-miR-23b-3p, bta-miR-24-3p, bta-miR-27a-3p, bta-miR-29a, bta-miR-324, bta-miR-326, bta-miR-345-3p, bta-miR-410, bta-miR-652, bta-miR-677, bta-miR-873 and bta-miR-708) and one (bta-miR-148b) in OF-EVs. These miRNAs were predicted to modulate several pathways such as Wnt, Hippo, MAPK, and lipid metabolism and degradation. Differences in miRNAs found in OF-EVs from the early luteal phase and UF-EVs from mid-luteal phase may reflect different environments to meet the changing needs of the embryo. Additionally, miRNAs may be involved, particularly in the uterus, in the regulation of embryo lipid metabolism, immune system, and implantation. This study evaluated miRNA cargo in OF-EVs from the early luteal phase and UF-EVs from the mid-luteal phase, coinciding with embryo transit within oviduct and uterus in vivo, and its possible influence on LMGs and signaling pathways crucial for early embryo development. A total of 333 miRNAs were detected, with 11 exclusive to OF, 59 to UF, and 263 were common between both groups.

CONCLUSIONS

Our study suggests that miRNAs within OF- and UF-EVs could modulate bovine embryo development and quality, providing insights into the intricate maternal-embryonic communication that might be involved in modulating lipid metabolism, immune response, and implantation during early pregnancy.

The severity of menopausal symptoms is associated with diabetes, and cardiometabolic risk factors in middle-aged women

BACKGROUND

Ovarian senescence is associated with increased cardiovascular risk. We aimed to evaluate the association between menopausal symptoms and cardiometabolic risk factors in a cohort of apparently healthy middle-aged women.

METHODS

The cohort included 2793 peri- and postmenopausal women not on menopausal hormone therapy. Demographic/anthropometric and biochemical/hormonal data were assessed. The severity of menopausal symptoms was evaluated by the Greene Climacteric Scale (GCS).

RESULTS

GCS-Total Score was associated with BMI (b=0.12, 95% CI: 0.04 to 0.20), T2DM (b=2.10, 95% CI: 0.06 to 4.15), and late-postmenopause (b=-1.24, 95% CI: -2.17 to -0.33). GCS-psychological score was associated with BMI (b=0.06, 95% CI: 0.00 to 0.11). GCS-Physical Score was associated with BMI (b=0.06, 95% CI: 0.03 to 0.09), central obesity (b=0.18, 95% CI: 0.02 to 0.34), and postmenopause (early-/late-postmenopause vs. perimenopause, b=-0.36, 95% CI: -0.59 to -0.13 and b=-0.65, 95% CI: -0.97 to -0.34, respectively). All GCS-scores were negatively associated with age. GCS-Sexual Score was associated with early-postmenopause (incidence rate ratio (IRR)=1.53, 95% CI: 1.21 to 1.94), central obesity (IRR=1.18, 95% CI: 1.00 to 1.39), smoking, diastolic blood pressure, age. Cox-regression analysis showed that incident T2DM was positively associated with increasing age, BMI, daily alcohol consumption, moderate-to-severe vasomotor symptoms (VMS, OR=1.045, 95% CI: 1.011 to 1.079), and negatively with moderate-to-strenuous physical activity. These associations persisted in lean but not in obese women.

CONCLUSIONS

The severity of menopausal symptoms is associated with T2DM, obesity, and smoking in a cohort of peri-/postmenopausal women. VMS were associated with incident T2DM, especially in lean women. These associations must be considered in implementing primary and secondary prevention strategies.

Serum Activin A as Brain Injury Biomarker in the First Three Days of Life. A Prospective Case-Control Longitudinal Study in Human Premature Neonates

Disruption of normal intrauterine brain development is a significant consequence of premature birth and may lead to serious complications, such as neonatal brain injury (NBI). This prospective case-control longitudinal study aimed at determining the levels and prognostic value of serum activin A during the first three days of life in human premature neonates which later developed NBI. It was conducted in a single tertiary hospital and eligible participants were live-born premature (<34 weeks) neonates. Each case (n = 29) developed NBI in the form of an intraventricular haemorrhage, or periventricular leukomalacia, and was matched according to birth weight and gestational age to one neonate with normal head ultrasound scans. Serum activin A levels in both groups showed a stable concentration during the first three days of life as no difference was observed within the two groups from the first to the third day. Neonates diagnosed with NBI had significantly higher activin A levels during the first two days of life compared to control neonates and its levels correlated to the severity of NBI during the second and third day of life. Although serum activin A on the second day was the best predictor for neonates at risk to develop NBI, the overall predictive value was marginally fair (area under the ROC-curve 69.2%). Activin A, in combination with other biomarkers, may provide the first clinically useful panel for the early detection of premature neonates at high risk of NBI.

Serum glial fibrillary acidic protein as a biomarker of brain injury in premature neonates

Neonatal brain injury is a serious adverse outcome of prematurity. Early detection of high risk premature neonates to develop neonatal brain injury is not currently feasible. The predictive value of many biomarkers has been tested, but none is used currently in clinical practice. The purpose of this study was to determine the levels and predictive value of serum glial fibrillary acidic protein (GFAP) in a prospective longitudinal case-control study during the first three days of life in premature neonates (<34 weeks of gestation) that later developed either intraventricular hemorrhage or periventricular leukomalacia. Each case (n=29) was matched according to birth weight and gestational age to one neonate with normal head ultrasound scans. No significant difference on GFAP levels was observed between the groups. Nevertheless, neonates with brain injury presented more frequently GFAP levels above the lowest detection limit (0.056 ng/ml) and this trend was significantly different during all days. The effectiveness of GFAP as an early biomarker of neonatal brain injury in premature neonates seems to be limited.

56 Nobiletin affects gene expression profiles of the ERK1/2 pathway in bovine embryos produced invitro

During embryo development the embryonic genome activation (EGA) is one of the most important events and in bovine embryos it occurs at the 8- to 16-cell stage. Invitro embryo production increases the levels of reactive oxygen species (ROS), which leads to the low quality of the produced blastocysts, possibly by affecting EGA. Nobiletin is an antioxidant that affects cell cycle regulation (Huang et al. 2016 Evid. Based. Complement. Alternat. Med. 2016, 2918796, https://doi.org/10.1155/2016/2918796). Therefore, we aimed to evaluate the effect of nobiletin supplementation, in two key periods of early embryo development, on blastocyst yield and expression of selected genes of the ERK1/2 pathway and oxidative stress on produced embryos. Invitro zygotes were cultured in synthetic oviductal fluid (SOF) with 5% fetal calf serum (control, C); C with 5 or 10µM nobiletin (MedChemExpress) (N5, N10); or C with 0.03% dimethyl sulfoxide (CDMSO; vehicle for nobiletin dilution) during the minor (21–54h post-insemination (hpi): 2- to 8-cell; MNEGA; 12 replicates) or major (54–96 hpi: 8- to 16-cell; MJEGA; 10 replicates) phase of EGA. The speed of development was considered and embryos that reached ≥8 cells at 54 hpi from MNEGA phase and ≥16 cells at 96 hpi from MJEGA phase, were selected and further cultured in control medium until Day 7. Embryos at ≥8 cell (MNEGA), ≥16 cell (MJEGA) stage, and Day 7 blastocysts from both periods were snap-frozen in liquid N2 for gene expression analysis (3 pools of 10 embryos/treatment). The expression of genes related to ERK1/2 pathway (H3–3B, H3–3A, NFE2L2) and oxidative stress (GPX1) were measured by quantitative PCR; H2AFZ and ACTB were used as housekeeping genes. Statistical analysis was assessed by one-way ANOVA. At 54 hpi, irrespective of nobiletin supplementation, no differences were found in the proportion of embryos that reached the 8-cell stage between groups in both phases (≈60%). At 96 hpi, nobiletin during MJEGA showed a higher proportion of embryos reaching the 16-cell stage than control groups (≈70% vs. ≈60%, respectively; P&lt;0.001). Blastocyst yield for MNEGA and MJEGA was higher (P&lt;0.001) for N5 (40.0±0.8% and 46.7±0.8%) and N10 (41.0±0.9% and 54.5±1.1%) compared with C (32.0±0.6% and 38.4±1.1%) and CDMSO (31.2±0.4% and 35.8±1.0%) groups, while N10 was higher (P&lt;0.05) compared to N5 group in MJEGA. The expression of H3–3B and H3–3A were higher (P&lt;0.05) in 8-cell embryos from N5 and N10 groups during MNEGA; while in 16-cell embryos, H3–3B and NFE2L2 were higher (P&lt;0.05) only in the N10 group compared with both controls during MJEGA. GPX1 was upregulated in nobiletin-supplemented groups from both phases (8- and 16-cell embryos and blastocysts) compared with controls (P&lt;0.05). In conclusion, nobiletin supplementation during minor or major EGA has a positive effect in pre-implantation embryo development and modifies the transcription of cell cycle and oxidative stress genes in early embryos. These benefits can be attributed to its bioactivity and indicate that it might be a tool to overcome EGA and ROS disorders in bovine invitro-produced embryos.This research was funded by MINECO-Spain AGL2015-70140-R, PID2019-111641RB-I00, RTI2018-093548-B-I00; SENESCYT-Ecuador; FAPESP-Brazil 2017/20339-3, CNPq-Brazil 304276/2018-9.

36 Analysis of miRNA content of oviduct and uterine extracellular vesicles across the bovine estrous cycle

With the aim of investigating the possible hormonal regulatory effect of the oestrous cycle on miRNA content in the extracellular vesicles (EVs) of bovine oviducal and uterine fluids (OF, UF), we performed a bioinformatic analysis of these miRNAs, their target genes, and their biological pathways. Reproductive tracts were collected from slaughtered heifers and selected according to their corpus luteum morphology, corresponding to the 4 stages of the oestrous cycle (n=5 per stage; S1: days 1 to 4, S2: days 5–10, S3: days 11–17, S4: days 18–20) and transported to the laboratory on ice. EVs were obtained by size exclusion chromatography (PURE-EVs-Hansa Biomed) from the flushing of 1.2mL and 2.5mL of OF and UF, respectively. To concentrate the EVs, they were ultracentrifuged and suspended in 100µL of PBS. Total RNA extraction was obtained from 70µL of the previous pellet, using miRNeasy Mini Kit (Qiagen). Then, 100 to 200ng of the obtained RNA was reverse transcribed using miScript II RT Kit (Qiagen). MicroRNA (miRNA) expression profiling was done by primer-based real-time quantitative PCR of 383 mature miRNA sequences. Possible miRNA target genes and their biological pathways were predicted using the miRWalk database. Among EV miRNAs in OF, bta-miR-130a, bta-miR-382, and bta-miR-1291 were the most abundant at all stages of the oestrous cycle, displaying a significantly progressive increase from stages 1 to 4 (P&lt;0.05). In UF, bta-miR-17-5p, bta-miR-206, bta-miR-22-5p, bta-miR-502a, and bta-miR-503-3p were the most abundant at all stages of the cycle, showing greater differences between S1 and S3 (P&lt;0.05). Other miRNAs were exclusively present in a specific stage of the oestrous cycle in OF: bta-miR-21-5p (S1), bta-miR-146a (S2), bta-miR-128 (S3), and bta-miR-147 (S4). In UF, bta-miR-218 (S1), bta-miR-208b (S2), bta-miR-340 (S3), and bta-miR-335 (S4) were found. Table 1 presents some of these miRNAs, their predicted target genes, and functional pathways. In conclusion, this study highlights the effect of the oestrous cycle on miRNAs contained in the EVs of OF and UF. These miRNAs are related to relevant biological pathways implicated in oviduct and uterus modulation across the cycle, but they may also prepare those organs for embryo/conceptus presence and development. Table 1. Micro (mi)RNAs of oviductal (OF) and uterine fluid (UF) extracellular vesicles (EVs), their target genes, and biological pathways Reproductive fluid miRNAs Target genes Target pathways OF bta-miR-130a BMPR2, SMAD5, SMAD4 BMP signalling bta-miR-1291 SLC2A1 Glucagon signalling bta-miR-21–5p LIF Pluripotency stem cells regulation UF bta-miR-17-5p STAT3 Prolactin signalling bta-miR-206 ESR1 Oestrogen signalling bta-miR-340 HRAS Ras/MAPK/ERK signalling (embryo implantation) This research was funded by MINECO-Spain AGL2015-70140-R, PID2019-111641RB-I00, RTI2018-093548-B-I00; SENESCYT-Ecuador (YNC); FAPESP-Brazil 2017/20339-3 (CLVL), 2014/22887-0 (JCS), 2019/04981-2 (RM); CNPq-Brazil 304276/2018-9, 420152/2018-0 (CLVL).

52 Extracellular vesicles from oviduct and uterus in sequential invitro culture affects mitochondrial activity and lipid metabolism transcripts in bovine embryos

Oviducal fluid (OF) and uterine fluid (UF) improve the quality of embryos during invitro culture, and their extracellular vesicles (EV) may be involved in such an effect. We aimed to evaluate the effect of EV from OF and UF in sequential invitro culture on the development and quality of bovine embryos. Zygotes were cultured in synthetic oviduct fluid supplemented either with 3mg mL−1 BSA (n=1584) or 5% EV-depleted fetal calf serum (dFCS, n=1594) in absence or presence (BSAEV, n=1853 and dFCSEV, n=1473) of 3×105 EV mL−1 from OF (Day 1 to Day 4) and UF (Day 5 to Day 8), mimicking invivo conditions. EV from oviducts (early luteal phase) and uterine horns (mid luteal phase) from slaughtered heifers were isolated by size exclusion chromatography; size and concentration were assessed by nanotracking analysis (NTA) and morphology by transmission electron microscopy (TEM). Blastocyst rate was recorded on Days 7–8 and their quality was assessed for mitochondrial activity by staining with Mitotracker Deep Red (ThermoFisher Scientific), survival rate after vitrification/warming by invitro culture for up to 72h, and relative mRNA abundance of lipid metabolism-related transcripts by quantitative PCR. Housekeeping genes were H2AFZ and ACTB. Data were analysed by one-way ANOVA and Tukey test. TEM confirmed the presence and morphology of EVs, and NTA indicated mode size and concentration of particles (137.2 and 151.2 nm; 2.97×1010 and 7.98×1010 particles mL−1, for OF and UF, respectively). Blastocyst yield was lower (P&lt;0.05) in BSA groups compared with dFCS groups (BSA: 16.2±1.5 and 31.0±1.9; BSAEV: 14.1±1.6 and 26.2±2.0% vs. dFCS: 30.5±2.0 and 40.6±2.4; dFCSEV: 31.1±2.5 and 39.8±2.7%, Day 7 and Day 8, respectively), irrespective of EV supplementation. Blastocyst mitochondrial activity was increased (P&lt;0.05) by EV in dFCSEV compared with the other groups. No differences in survival rate after vitrification/warming were found (range at 72 h: 67.1±8.1 to 87.8±5.7%). PPARGC1B was downregulated and ACC upregulated by EV, irrespective of protein source in medium (P&lt;0.05). In contrast, EV affected some transcripts depending on the protein source in the medium (CD36 upregulated in dFCSEV, downregulated in BSAEV; PLIN2 downregulated in dFCSEV and ATGL downregulated in BSAEV, P&lt;0.05). In conclusion, mimicking physiological conditions using EV from OF and UF in sequential IVC does not affect development but improves embryo quality by increasing blastocysts’ mitochondrial activity and favours the expression of specific lipid metabolism transcripts. Functional effects of EV may be influenced by the protein source in the medium. This research was funded by MINECO-Spain AGL2015-70140-R, PID2019-111641RB-I00, RTI2018-093548-B-I00; YN Cajas, SENESCYT-Ecuador; CLV Leal, FAPESP-Brazil 2017/20339-3, CNPq-Brazil 304276/2018-9.

Anti-Mullerian hormone concentrations are inversely associated with subclinical atherosclerosis in premenopausal women

Background

Anti-Müllerian hormone (AMH) constitutes a marker of ovarian reserve and appears to have a predictive role regarding the time of menopause. Moreover, AMH is associated with adverse cardiac events. History of premature menopause and early onset of menopause have been associated with increased risk of cardiovascular (CV) disease. In addition, menopausal transition and duration of menopause have been associated with increased burden of subclinical atherosclerosis. However, the association between AMH as a marker of female reproductive age with atherosclerosis in premenopausal women is currently unknown.

Purpose

To investigate whether AMH concentrations are associated with markers of early atherosclerosis in healthy, normally menstruating women.

Methods

In a cross-sectional study, vascular structure and function were assessed by measurement of carotid and femoral intima-media thickness (IMT), lipid profile and serum AMH concentrations were assessed. Exclusion criteria were clinically overt CV disease, abnormal ovulatory cycles, polycystic ovarian syndrome, acute infection or chronic inflammatory disease, risk factors for CV disease and any medication

Results

Seventy premenopausal women, aged 32.7±6.5 years, were included. Mean AMH levels were lower in smokers than in non-smokers and negatively associated with total cholesterol (TC) levels. An inverse association between mean AMH concentrations and IMT in all segments was observed. No correlation with other markers of subclinical atherosclerosis or traditional CV risk factors was found. After multi-variable adjustment for traditional CV risk factors, the association between AMH concentrations combined IMT and carotid bulb IMT, remained significant.

Conclusions

In healthy, normally ovulating women, low AMH concentrations are associated with an adverse lipid profile and subclinical atherosclerosis, independently of traditional CV risk factors. This finding suggest a role of decreased follicular reserve with atherosclerotic disease.

Funding Acknowledgement

Type of funding source: None

Fertilizing capacity of vitrified stallion sperm assessed utilizing heterologous IVF after different semen warming procedures

The aim of this study was to evaluate the fertilizing capacity of frozen or vitrified stallion sperm after assessing different warming procedures. In Experiment 1, different warming procedures were compared after sperm vitrification: immersion in extender at 43 °C (C), or in a water bath at 37 °C/30 s (W37), 43 °C/10 s (W43) or 60 °C/5 s (W60). With the W60 treatment, there were greater values (P < 0.05) for VCL (83.93 ± 3.6 μm/s) and ALH (3.00 ± 0.2 μm) than freezing and with the C group, and greater values (P < 0.001) for PM (35.33 ± 2.5 %) than with the W43 treatment. In Experiment 2, the fertilizing capacity of vitrified and frozen sperm was assessed utilizing heterologous IVF procedures, using cattle oocytes. Vitrification resulted in greater values (P < 0.05) than freezing for the number of bound sperm (1.36 ± 0.3 and 0.69 ± 0.2, respectively). There were no differences between frozen or vitrified sperm in pronuclear formation (26 hours post-insemination - hpi; 14.08 ± 4.2 % and 22.78 ± 4.8 %, respectively) or cleavage rate (32.77 ± 4.3 % and 39.66 ± 4.6 %, respectively). In conclusion, vitrified stallion sperm warmed in a water bath at 60 ºC had the capacity to penetrate cattle oocytes, leading to pronuclear formation and hybrid embryo cleavage after heterologous IVF.

S100B as a biomarker of brain injury in premature neonates. A prospective case - control longitudinal study

BACKGROUND

Neonatal brain injury (NBI) is a serious adverse outcome in premature neonates. We sought to determine the levels and prognostic value of serum S100B during the first three days of life in premature neonates (<34 weeks) that later developed NBI in the form of either intraventricular hemorrhage (IVH) or periventricular leukomalacia (PVL).

METHODS

This is a prospective case - control longitudinal study. Each case (n = 29) was matched according to birthweight and gestational age to one neonate with normal head ultrasound scans.

RESULTS

Neonates with NBI, had significantly higher S100B concentration during the first three days of life. In both groups S100B was significantly higher on the first day when compared to the next two days of life showing a downwards trend. Serum S100B on the first day was the best predictor for adverse neonatal outcome such as death or II-IV IVH grade. A cut-off value of 10.51 ng/ml serum S100B performed a sensitivity of 100% and a specificity of 93.9% to predict adverse neonatal outcome.

CONCLUSION

Further research on the predictive value of serum S100B regarding NBI in premature neonates is of great interest and may provide the first clinically useful biomarker for early detection of neonates at high risk.

Inhibiting diacylglycerol acyltransferase-1 reduces lipid biosynthesis in bovine blastocysts produced in vitro

Diacylglycerol acyltransferase-1 (DGAT1) is one of the DGAT enzymes that catalyzes the final step in the synthesis of triacylglycerol, which is a major component of the lipid droplets in embryos. Intracellular lipids accumulated in embryos produced in vitro have been associated with reduced cryotolerance and quality. The objective of the present study was to investigate the influence of DGAT1 inhibition on embryo development, quality, and post-vitrification survival, in addition to expression profiles of selected lipid metabolism-regulating and oxidative stress genes. Bovine cumulus-oocyte complexes were matured and fertilized in vitro and were cultured in synthetic oviduct fluid (SOF) supplemented with 5% fetal calf serum (FCS) alone (Control) or with 1, 5, 10 or 50 μM DGAT1 inhibitor (A922500®; D1, D5, D10, and D50, respectively) or 0.1% dimethyl sulfoxide (CDMSO: vehicle for DGAT1 inhibitor dilution) from 54 h post-insemination until Day 8 post insemination. No differences were found in blastocyst yield on days 7 and 8 in Control, CDMSO, D10, and D50 groups. Embryos cultured with 10 or 50 μM DGAT1 inhibitor had greater mitochondrial activity (P < 0.01), and increased number of cells (P < 0.05), while the cytoplasmic lipid content was reduced (P < 0.01), the latter associated with altered expression profiles of selected genes regulating lipid metabolism or genes related with oxidative stress (transcript abundance increased for SLC2A1 and SLC2A5 and decreased for DGAT1 and GPX1). Importantly, the survival rate of blastocysts produced with 10 μM DGAT1 was higher than that of Control, CDMSO and D50 groups at 72 h after vitrification and warming (73.8 vs 57.1, 55.9 and 56.1%, respectively, P < 0.001). In conclusion, inhibition of DGAT1 synthesis in bovine embryos produced in vitro abrogates the negative effect of FCS by decreasing their lipid content, increasing mitochondria activity and improving embryo cryotolerance, as well as favoring the expression of lipid metabolism regulating and oxidative stress-related transcripts.

76 Extracellular vesicles from oviduct and uterus in sequential culture improve the quality of bovine embryos produced invitro

Extracellular vesicles (EVs) are released by cells and transport cargo that affect functions of other cells. Oviductal fluid (OF) and uterine fluid (UF) have been shown to improve quality of embryos during invitro culture (Hamdi et al. 2017 Reprod. Fertil. Dev. 30, 935-945) which may be due to their content of EV (Lopera-Vásquez et al. 2017 Reproduction 153, 461-470). Thus, the aim of this study was to evaluate the effect of EVs from OF and UF on a sequential invitro culture system on the development and quality of bovine embryos. Zygotes were cultured in synthetic oviduct fluid (SOF) supplemented with 3mgmL−1 bovine serum albumin (BSA; n=1228) or 5% EV-depleted fetal calf serum (dFCS, n=1261) in the presence (BSAEV, n=1265 and dFCSEV, n=1253) or absence of 3×105 EVmL−1 from OF (Day 1 to Day 4) and UF (Day 4 to Day 9), mimicking invivo conditions. The EVs pooled from 5 oviducts (early luteal phase) and 5 uterine horns (middle luteal phase) from slaughtered heifers were isolated by a Size Exclusion Chromatography kit (Hansa BioMed). The EV size and concentration were assessed by the nanotracking analysis system and morphology by transmission electron microscopy. Embryo development was recorded on Days 7/9. Day 7/8 blastocysts were assessed for quality by staining with (a) Hoechst 33342 (10 µgmL−1, 30min) for total cell number, (b) Bodipy 493/503 (20 µgmL−1, 1h) for lipid content (lipid droplet area in µm2), and (c) for survival rate after vitrification/warming. Data were analysed by one-way ANOVA and Tukey test. The EV concentration was 2.97 and 7.98×1010 particlesmL−1, and mode size 137.2 and 151.2nm for OF and UF, respectively. Transmission electron microscopy confirmed EV presence and size, showing typical cup-shaped morphology. Blastocyst yield was lower (P&lt;0.05) on Day 7 in the BSA groups (BSA: 15.7±1.9 and BSAEV: 15.2.4%) compared with serum groups (dFCS: 28.1±2.6 and dFCSEV: 30.1±2.9%) irrespective of EV supplementation; however, these differences were compensated at Days 8 and 9 (range: 30.0±3.2-40.8±3.9%). The EVs increased (P&lt;0.05) blastocyst total cell number in dFCSEV (152.6±2.9) and BSAEV (140.5±1.5) compared with dFCS (117.9±2.0) and BSA groups (122.4±1.1). However, lipid content was decreased (P&lt;0.05) in the presence of EVs only in dFCSEV (0.231±0.05µm2) compared with BSA (0.393±0.03µm2) and BSAEV (0.379±0.03µm2) groups. The dFCS did not differ from any group (0.371±0.05µm2; P&gt;0.05). Blastocyst survival after vitrification/warming was high in all groups up to 72h (range: 80.0±3.8-100%; P&gt;0.05). In conclusion, mimicking physiological conditions using EV from OF and UF during invitro culture does not affect development but improves embryo quality by increasing blastocyst total cell numbers and decreasing lipid contents. These results provide evidence of the association of the reproductive tract environment and developing embryo, confirming embryo-maternal communication. Funding was provided by MINECO-Spain AGL2015-70140-R; Y. N. Cajas, SENESCYT-Ecuador; C. L. V. Leal, FAPESP-Brazil 2017/20339-3.

75 Expression of lipid metabolism-related genes in bovine embryos cultured invitro with diacylglycerol acyltransferase-1 inhibitor

Intracellular lipids accumulated in embryos produced invitro have been linked to reductions in both quality and post-cryopreservation viability. Diacylglycerol O-acyltransferase 1 (DGAT1) is an enzyme that catalyzes the final step in triglyceride synthesis, which is a major component of the lipid droplets in embryos. Thus, the aim of this study was to evaluate the development and quality, in regard to changes in the expression of candidate genes of lipid metabolism, of bovine blastocysts cultured invitro with DGAT1 inhibitor (A922500 Sigma-Aldrich). Zygotes were cultured in synthetic oviduct fluid supplemented with 5% FCS (TC) or in TC supplemented with 10 or 50 µM DGAT1 inhibitor (T10 and T50, respectively) or TC with 0.1% dimethyl sulfoxide (TDMSO: vehicle for DGAT1 dilution) from 54h post-insemination (hpi; major embryonic genome activation, EGA) until Day 8. Cleavage rate (48 hpi) and blastocyst yield (Day 7-8) were evaluated. Day 7 blastocysts were snap-frozen in LN2 for gene expression analysis. The mRNA abundance of candidate genes related to lipid metabolism (DGAT1, PLIN2, GLUT5, GLUT1, GPX1, PPAR1b, and G6PD) was measured by quantitative PCR. The H2AFZ and ACTB genes were used as housekeeping genes. Statistical analysis was assessed by one-way analysis of variance. No differences were found in cleavage rate, whereas blastocyst yield at Day 8 was higher (P&lt;0.05) for T50 (30.5±0.5%) and TC (29.7±0.5%) compared with T10 (25.6±0.5%) and TDMSO (27.1±0.8%). The expression of genes regulating lipid droplet formation (DGAT1 and PLIN2) was down-regulated in embryos of T10 and T50 groups compared with controls (P&lt;0.05) only for DGAT1, whereas no differences were observed for PLIN2. The expression of GLUT5, a fructose metabolism transporter gene, was only increased in embryos in the T10 group, whereas the relative abundance of GLUT1 (involved in glucose metabolism) was up-regulated in T10 and T50 groups compared with controls (P&lt;0.05). The GPX1 gene was decreased significantly in embryos from both DGAT1-inhibitor groups compared with the controls. The expression profile of PPAR1b and G6PD, lipid metabolism-regulating genes, were not different among embryo groups. In conclusion, supplementation of embryo culture with DGAT1 inhibitor improves development and blastocyst quality in terms of the expression of lipid metabolism-regulating genes, supporting a relationship between lipid metabolism and embryo feature. Funding was provided by MINECO-Spain AGL2015-70140-R &amp; RTI2018-093548-B-I00; J. Giraldo-Giraldo COLCIENCIAS 727/2015-Colombia; Y. N. Cajas, SENESCYT-Ecuador; C. L. V. Leal, FAPESP-Brasil 2017/20339-3.

77 Nobiletin supplementation affects gene expression profiles of the Akt pathway in bovine embryos invitro

Embryonic genome activation (EGA) is a critical event in early embryonic development and occurs in 8-16-cell stage embryos in bovine. Invitro embryo production increases reactive oxygen species (ROS), leading to low yield and cell death. Nobiletin is an antioxidant that inhibits ROS production and affects cell cycle regulation. The aim of this study was to evaluate the effect of nobiletin supplementation in two key periods of early embryo development on blastocyst yield and expression of candidate genes of the Akt pathway. Invitro-produced zygotes were cultured in synthetic oviductal fluid supplemented with 5% FCS (control; C); C with 5 or 10 µM nobiletin (MedChemExpress; N5, N10) or C with 0.03% dimethyl sulfoxide (CD vehicle for nobiletin dilution) during the minor (2-8-cell stage; MNEGA) or major (8-16-cell stage; MJEGA) phase of EGA, considered as two separate experiments. For all groups, the speed of development was considered, and normally developing embryos that reach ≥8 cells at 54h post-insemination and ≥16 cells at 96h post-insemination were selected and cultured in control medium until Day 8, respectively. Embryos at ≥8-cell stage (N5/N10 MNEGA), 16-cell stage (N5/N10MJEGA), and Day 7 blastocysts of both periods were snap-frozen in LN2 for gene expression analysis. Cleavage rate and blastocyst yield (Day 7-8) were evaluated. The mRNA abundance of candidate genes related to the Akt pathway (CDK2, PGC1A, PPARG, RPS6KB1) and oxidative stress (GPX1) was measured by quantitative PCR. The H2AFZ and ACTB genes were used as housekeeping genes. Statistical analysis was assessed by one-way ANOVA. Nobiletin supplementation during MNEGA showed no differences in cleavage rate, whereas the blastocyst yield at Day 8 was higher (P&lt;0.001) for N5 (42.9±1.4%) and N10 (45.3±2.1%) compared with C (32.9±1.1%) and CD (32.6±1.4%) groups. When nobiletin was supplemented during MJEGA, no differences were found in cleavage rate; however, Day 8 blastocyst yield was higher (P&lt;0.001) for N10 (61.8±0.7%) compared with C (45.2±1.7%), CD (43.6±1.4%), and N5 (52.1±2.1%) groups, whereas N5 was higher (P&lt;0.05) compared with both control groups. The mRNA abundance of CDK2 significantly increases in 8-cell stage embryos from N5 and N10 groups during MNEGA, whereas 16-cell stage embryos from N10 group during MJEGA showed a significant increase compared with both controls (P&lt;0.05). The expression of PGC1A was significantly higher in blastocysts from N5, N10 during MNEGA, and N10 during MJEGA groups compared with both controls (P&lt;0.05). No differences were observed for PPARG and RPS6KB1 in any group from both phases. GPX1, an oxidative indicator gene, was up-regulated in all nobiletin-supplemented groups from both phases compared with controls (P&lt;0.05). In conclusion, supplementation of embryo culture during MNEGA or MJEGA with nobiletin improves embryo development and induces changes in the transcriptional genes related to cell cycle regulation and oxidative stress. This suggests that nobiletin acts through the Akt pathway during the first stages of embryonic development. Funding was provided by MINECO-Spain AGL2015-70140-R&amp;RTI2018-093548-B-I00; Y. N. Cajas, SENESCYT-Ecuador; C. L. V. Leal, FAPESP-Brasil 2017/20339-3.

Postpartum human breast milk levels of neutrophil gelatinase-associated lipocalin (NGAL) and matrix metalloproteinase-9 (MMP-9)/NGAL complex in normal and pregnancies complicated with insulin-dependent gestational diabetes mellitus. A prospective pilot case-control study

Neutrophil gelatinase-associated lipocalin (NGAL) and its complex with matrix metalloproteinase-9 (MMP-9) are present in a variety of human tissues and extracellular fluids. The aim of this pilot prospective case-control study was to detect NGAL and MMP-9/NGAL complex in human breast milk postpartum in women with normal and pregnancies that developed insulin-depended gestational diabetes mellitus (iGDM). We detected both biomarkers in human breast milk and concentrations were determined at the first day of colostrum secretion and two days after, in 22 normal pregnancies and 13 pregnancies with iGDM. Mean NGAL concentration decreased significantly from the first to the second sample, in both groups. Mean MMP-9/NGAL complex concentration decreased also significantly from the first to the second sample in normal pregnancies. Mean complex concentration was significantly higher in diabetic pregnancies compared to normal ones in the second sample.IMPACT STATEMENTWhat is already known on this subject? There is limited information on the presence of Neutrophil gelatinase-associated lipocalin (NGAL) in human milk and its physiological role.What the results of this study add? It is the first time that MMP-9/NGAL complex is detected in human milk in both normal and pregnancies complicated with insulin-depended gestational diabetes mellitus (iGDM). We confirm the presence of NGAL in colostrum of normal pregnancies and for the first time we detected NGAL in milk of pregnancies with iGDM. Concentrations of NGAL and MMP-9/NGAL complex tend to lessen postpartum in both groups. Pregnancies with iGDM compared to normal ones showed significantly higher concentration of MMP-9/NGAL complex two days after the beginning of lactation.What the implications are of these findings for clinical practice and/or further research? Further studies are necessary to determine the levels of NGAL and MMP-9/NGAL complex in human milk postpartum in normal and pathological pregnancies. Taking into consideration the well-established NGAL's ability to act as a bacteriostatic agent and its mucosal healing activity in gastrointestinal track, early breastfeeding of neonates is a logical recommendation. Finally, new studies on the actual physiological role of milk NGAL in neonates are necessary.

The European Federation of Clinical Chemistry and Laboratory Medicine syllabus for postgraduate education and training for Specialists in Laboratory Medicine: version 5 - 2018

Although laboratory medicine practise varies across the European Union's (EU) member states, the extent of overlap in scope is such that a common syllabus describing the education and training associated with high-quality, specialist practise can be identified. In turn, such a syllabus can help define the common set of skills, knowledge and competence in a Common Training Framework (CTF) for non-medical Specialists in Laboratory Medicine under EU Directive 2013/55/EU (The recognition of Professional Qualifications). In meeting the requirements of the directive's CTF patient safety is particularly enhanced when specialists seek to capitalise on opportunities for free professional migration across EU borders. In updating the fourth syllabus, the fifth expands on individual discipline requirements, new analytical techniques and use of statistics. An outline structure for a training programme is proposed together with expected responsibilities of trainees and trainers; reference is provided to a trainee's log book. In updating the syllabus, it continues to support national programmes and the aims of EU Directive 2013/55/EU in providing safeguards to professional mobility across European borders at a time when the demand for highly qualified professionals is increasing in the face of a disparity in their distribution across Europe. In support of achieving a CTF, the syllabus represents EFLM's position statement for the education and training that underpins the framework.

Influence of sperm filtration and the addition of glycerol to UHT skimmed milk- and TEST-based extenders on the quality and fertilizing capacity of chilled ram sperm

The poor fertility of ram semen stored chilled for long periods has encouraged the development of protocols designed to improve the kinetic vigour and cervical barrier-crossing capacity of sperm. The present work evaluated the effect of sperm selection with Sephadex filtration and the supplementation of 2% glycerol (GLY) to extenders based on ultra-heat-treated skimmed milk (UHT) or Tris-Tes-Glucose (TEST) on ram sperm kinetic parameters, plasma membrane integrity, acrosome integrity, mitochondrial function and fertilizing ability, over long chilling times. The results showed that for non-filtered semen, values for progressive sperm motility (%PSM), straight line velocity (VSL, μm/s) and the percentage of sperm with an intact plasma membrane/intact acrosome/a high mitochondrial function index (%IPIAHM) at all times up to 96 h of chilling were higher when the UHT extender (P < 0.01) was used compared to TEST extender irrespective of the presence of GLY. When semen was previously filtered with Sephadex, the addition of GLY to the UHT extender improved total motility (%TM), the %PSM and the VSL at 96 h compared to all other treatments (P < 0.01). The best results of all were obtained with non-filtered semen and UHT either with or without GLY. Heterologous IVF using zona-intact bovine oocytes was used to assess the fertilizing capacity of non-filtered fresh (FS0), chilled-for-24 h (CS24) or chilled-for-48 h (CS48) ram semen diluted in UHT extender (GLY-free). Heterologous IVF showed that ram sperm, either FS0, CS24 or CS48, were equally capable of penetrating zona pellucida intact bovine oocytes, leading to pronuclear formation and hybrid embryo cleavage (46.3 ± 3.2; 48.8 ± 3.2; and 43.3 ± 3.5, respectively). No differences were seen with respect to fresh sperm in terms of sperm binding, penetration, polyspermy, pronucleus formation or cleavage rates (P > 0.05). In conclusion, neither Sephadex filtration nor addition of glycerol provided extra benefits to ram sperm chilled up to 96 h. Chilled, non-filtered sperm extended with UHT without GLY showed better sperm functionality than did similar sperm extended with TEST extenders. Indeed, sperm diluted in UHT extender, maintained fertilizing ability up to 48 h.

Gestational Diabetes and T-cell (Th1/Th2/Th17/Treg) Immune Profile

BACKGROUND/AIM

Gestational diabetes mellitus (GDM) is a common pregnancy complication, characterized by insulin resistance and low-grade systemic inflammation with a pro-inflammatory immune system response. Our objective was to study the peripheral Th1, Th2, Th17 and Treg response in GDM compared to normal pregnancy.

MATERIALS AND METHODS

Th1, Th2, Th17 and Treg subsets was determined by flow cytometry based on staining for specific intracellular cytokines, as well as C-reactive protein (CRP) and total IgE circulating levels. The health status of all offspring was also assessed 6 months post-delivery.

RESULTS

A total of 49 Caucasian adult pregnant women were enrolled into a GDM (n=26) and Control (n=23) group. At the third trimester of pregnancy, the GDM group had a higher proportion of Th2, Th17 and Treg cells compared to control. Contrary to the control group, the GDM group exhibited no significant change in the Th1/Th2/Th17/Treg profile postpartum. Furthermore, higher circulating CRP and total IgE levels were noted in the GDM group compared to controls. At the 6-month post-delivery assessment, 30.8% of the offspring from the GDM group were found to have developed atopic dermatitis, food allergy or allergic proctocolitis compared to none from the control group.

CONCLUSION

Compared to an uncomplicated pregnancy, GDM exhibits a significantly different peripheral T-cell profile at the third pregnancy trimester characterized by higher proportion of Th2, Th17 and Treg cells which persist six months post-delivery, while the increased high sensitivity CRP (hsCRP) levels stressed the low-grade inflammatory profile of this disease.

175 Nobiletin enhances the quality of in vitro-matured bovine oocytes and blastocysts by altering the transcription of key developmental genes

One of the problems associated with in vitro production of embryos in bovine is the increase in reactive oxygen species (ROS), which leads to cell alterations and death. Nobiletin is a polymethoxyflavone isolated from citrus fruits with various beneficial effects on cell cycle regulation and inhibition of ROS production. In a preliminary study, we demonstrated that supplementation of 25 or 50 µM nobiletin to the in vitro maturation (IVM) medium reduces oxidative stress and improves oocyte nuclear and cytoplasmic maturation and embryo development. Thus, in this study, we aimed to evaluate the antioxidant activity of nobiletin during IVM on bovine matured oocytes, their cumulus cells (CC), and blastocysts by quantitative changes of gene expression. Immature cumulus oocytes complexes (COC) were aspirated from ovaries of slaughtered heifers. Selected COC underwent IVM in TCM-199+10% FCS and 10ng mL−1 epidermal growth factor (EGF; Control) supplemented with 25 µM (Nob25) or 50 µM (Nob50) nobiletin (MedChemExpress, Monmouth Junction, NJ, USA) or 0.001% dimethyl sulfoxide (DMSO control), a vehicle for nobiletin dilution, in 5% CO2 in air at 38.5°C. After 24h, 50 matured oocytes/group and their CC were snap-frozen in LN2 for gene expression analysis. The remaining oocytes were fertilized (Day 0) and cultured in vitro. Blastocysts (Day 7; n=50/group) were snap-frozen in LN2 for gene expression analysis (5 replicates). The mRNA abundance of candidate genes related with oxidative stress (SOD2, CYP51); apoptosis (BAX); quality (BMP15, BMP7, CLIC1, MAPK1, ABCB1); and cell junction (GJA1) was measured by quantitative PCR; H2AFZ and 18S rRNA were used as housekeeping genes. Statistical significance was assessed by one-way ANOVA. Supplementation of IVM medium with Nob25 or Nob50 produced changes in the expression levels of genes related to oxidative stress and apoptosis during IVM compared with controls. SOD2 and CYP51 were down-regulated in oocytes and CC (P&lt;0.05) but not in blastocysts, whereas BAX was down-regulated only in CC (P&lt;0.05). Nobiletin supplementation in IVM increased the expression of MAPK1 in oocytes and blastocysts (P&lt;0.05); however, no differences were observed in CC. BMP15 for oocytes and their CC and GJA1 for CC were up-regulated in Nob25 and Nob50 groups compared with controls (P&lt;0.05). The relative abundance of CLIC1 decreased in blastocysts from both nobiletin groups compared with controls (P&lt;0.05). No significant differences in the expression in ABCB1 and BMP7 were detected. In conclusion, our results suggest that supplementation of 25 or 50 µM nobiletin to the IVM medium reduces oxidative stress in oocytes and CC, decreases CC apoptosis, and provokes positive changes in the expression of genes related to oocyte and embryo quality. This research was supported by Spanish MINECO (AGL2015-70140-R and AGL2015-66145-R). Y. N. Cajas was supported by a grant from SENESCYT-Ecuador.

137 Assessment of fertilizing ability of Merino ram semen cold stored up to 48h by heterologous IVF of bovine oocytes

The use of cold-stored ram semen has been applied in sheep AI programs, because it preserves its fertilizing ability similar to fresh. Besides, the heterologous IVF has been successfully employed to assess semen fertilizing ability in several species. Hence, we aimed to evaluate the fertilizing ability of ram semen cold stored up to 48h at 5°C by assessing heterologous IVF using bovine oocytes. Fifteen pools of 3 normospermic Merino ram (2-7 years) ejaculates were collected using artificial vagina, diluted to 200×106 spermatozoa mL−1 with ultra-heat-treatment-based extender (skim milk-6% egg yolk) and cold stored up to 48h. In vitro matured zona-intact bovine oocytes were subjected to heterologous IVF using fresh semen (FS, n=707), semen cold stored to 24h (CS24, n=832) or semen cold stored to 48h (CS48, n=611). In parallel, homologous IVF (control, n=1356) and parthenogenesis (parth control non-fertilized oocytes, n=334) were performed. Ram non-selected and selected (BoviPure, Nidacon International, Mölndal, Sweden) semen parameters were evaluated by computer-assisted semen analysis. Sperm-oocyte interaction was assessed at 2.5h post-insemination (hpi) by evaluating the number of bound spermatozoa, whereas penetration and polyspermy were evaluated after 12 hpi. Presumptive zygotes were fixed and stained with Hoechst 33342 at 18, 20, 22, 24 and 26 hpi to assess pronuclear formation using phase contrast and confocal microscopy. Cleavage rate was evaluated in all groups at 48 hpi. Data obtained from 5 replicates were analysed using one-way ANOVA. Data was expressed as mean±standard error of the mean. In terms of sperm storage time, non-selected semen showed a significant decrease (P&lt;0.05) for CS24 and CS48 compared with FS on progressive motility [SPM (%): 52.30±4.1 and 36.9±5.5v. 71.3±1.6] and straight-line velocity (mm s−1: 132.2±6.1 and 109.7±6.3v. 176.7±4.3), respectively. However, selected semen showed a decrease (P&lt;0.05) only for CS48 when compared with CS24 or FS on SPM (35.6±3.9v. 56.1±6.91 and 59.3±2.6) and straight-line velocity (83.5±4.4v. 105.3±6.5 and 110±2.0), respectively. No differences were observed between heterologous IVF groups in all parameters evaluated. Homologous IVF showed a higher percentage of penetration only when compared with heterologous FS group (44.4±6.8v.12.5±4.5%; P&lt;0.01). The polyspermy was higher in heterologous CS24 group when compared with homologous IVF (11.4±3.4v. 3.8±2.2; P&lt;0.05). The homologous IVF group, as expected, showed the higher percentage of pronuclear formation at 18 hpi compared with heterologous IVF with FS (67.3±5.8v. 35.2±5.6%), CS24 (72.1±4.5 v. 37.2±5.7%) and CS48 (63.0±6.0 v. 27.0±5.6%), respectively (P&lt;0.001). Likewise, cleavage rate was higher in homologous group compared with heterologous IVF and parthenogenetic groups for FS (78.3±2.6.8v. 46.3±3.2 and 7.0±2.3%), CS24 (78.4±2.6 v. 48.3±3.2 and 4.9±2.0%), and CS48 (78.4±3.3 v. 43.3±3.5 and 4.3±1.2%), respectively (P&lt;0.001). In conclusion, Merino ram semen cold stored up to 48h maintains its fertilization ability to the same extend as fresh and can be used for sheep crossbreeding programs.

Prenatal Screening for Chromosomal Abnormalities: Where do We Stand Today in Mediterranean Countries?

Over the last 4 decades the practice of prenatal screening has evolved from the second-trimester triple test to complex combinations of biophysical and biochemical testing for aneuploidy, testing of fetal DNA in the maternal circulation and development of screening tests for adverse pregnancy outcomes. Presently, combined test in the 1^st trimester is the preferred multimarker screening protocol in most countries. Since 2010, cell-free fetal DNA (cffDNA) in maternal plasma, in combination with the next generation sequencing techniques, made a big breakthrough step in screening for Down Syndrome (DS) and other aneuploidies. It seems that the position of cffDNA in the current screening strategies is a secondary contingent use to combined test, at least as long as its price is still high and its use as a primary test is not cost effective. Concerning the situation in Mediterranean countries, at least with those who answered the questionnaire, screening in the 1^st trimester is an established practice, reimbursed from social security organizations, and not compulsory. cffDNA is used in all countries and its average cost is about 500 €.

Ovarian volume is associated with adiposity measures and bone mineral density in postmenopausal women

INTRODUCTION

The present study aimed to assess the association between ovarian volume and demographic and anthropometric parameters, as well as sex hormones and bone mineral density (BMD) in postmenopausal women.

METHODS

161 healthy postmenopausal women participated in this cross-sectional study. Fasting venous blood samples were obtained for biochemical/hormonal assessment. Anthropometric parameters included body mass index (BMI) and waist-to-hip ratio (WHR). Ultrasonography was used to estimate the average ovarian volume for each participant. BMD was measured in the femoral neck (FN) and the lumbar spine (LS) using DXA.

RESULTS

Mean ovarian volume increased linearly with increasing quartiles of BMI (Q1:0.985±0.25, Q2: 1.11±0.29, Q3: 1.07±0.28, Q4: 1.19±0.38, p-value for linear trend 0.013). Ovarian volume correlated positively with BMI (r=0.128, p-value=0.038), FN BMD (r=0.233, p-value=0.003), FN T-score (r=0.223, p-value=0.004) and FN Z-score (r=0.171, p-value=0.027). Multivariate analysis showed that ovarian volume was predicted by WHR (b-coefficient=0.157, p-value=0.047) and SHBG (b-coefficient= -0.160, p-value=0.042), independently of age and BMI. Finally, FN BMD was predicted by ovarian volume, independently of age, menopausal age and BMI.

CONCLUSION

Ovarian volume was positively and independently associated with adiposity indexes and femoral BMD in postmenopausal women. Lower SHBG levels were associated with higher ovarian volume. Insulin resistance may mediate these results. The significance of these findings should be assessed in larger prospective studies.

Effects of the HDAC inhibitor scriptaid on the in vitro development of bovine embryos and on imprinting gene expression levels

This study examines the effects of the histone deacetylation inhibitor scriptaid (SCR) on preimplantation embryo development in vitro and on imprinting gene expression. We hypothesized that SCR would increase histone acetylation levels, enhance embryonic genome activation, and regulate imprinting and X-chromosome inactivation (XCI) in in vitro produced bovine embryos. Zygotes were cultured in vitro in presence or absence of SCR added at different time points. We assessed cleavage and blastocyst rates as well as the quality of blastocysts through: (i) differential cell counts; (ii) survival after vitrification/thawing and (iii) gene expression analysis -including imprinted genes. Blastocyst yields were not different in the control and experimental groups. While no significant differences were observed between groups in total cell or trophectoderm cell numbers, SCR treatment reduced the number of inner cell mass cells and improved the survival of vitrified embryos. Further, genes involved in the mechanism of paternal imprinting (GRB10, GNAS, XIST) were downregulated in presence of SCR compared with controls. These observations suggest SCR prevents deacetylation of paternally imprinting control regions and/or their up-regulation, as these events took place in controls. Whether or not such reductions in XIST and imprinting gene expression are beneficial for post implantation development remains to be clarified.

116 In Vitro Transcriptomic Response of Bovine Oviduct Epithelial Cells to Direct or Indirect Embryo Contact

We observed that in vitro transcriptomic response of bovine oviduct epithelial cells (BOEC) to the early embryo could be the result of a contact-dependent signalling effect or interactions with embryo secretions. In order to determine this, BOEC were co-cultured directly with embryos or indirectly with embryo-conditioned media (CM); BOEC from the isthmus of oviducts at early luteal phase were cultured with TCM-199+10% fetal calf serum (FCS) in 4-well plates in 5% CO2 in air at 38.5°C for 6 days until confluence. In vitro 2- and 8-cell embryos as well as their CM were produced in parallel. A day before co-culture, BOEC medium was replaced with SOF+10% FCS. Groups for 2- and 8-cell embryos were established: BOEC in direct contact with embryos; BOEC in the same well as embryos but not in indirect contact; BOEC with embryo CM; and BOEC without embryos, as a control. Polyester mesh was used to maintain embryos position on top of the cells. After 48 h of co-culture, BOEC were recovered for gene expression analysis (4 replicates). The relative abundance of candidate genes previously shown to be affected by the presence of embryo in vivo (Maillo et al. 2015 Biol Reprod. 92, 144) [SMAD6 (BMP signalling pathway); ROCK1, ROCK2 (cytokinesis); SOCS3 (inflammatory response); PRELP (extracellular matrix)] or in vitro (Schmaltz-Panneau et al. 2014 Anim. Reprod. Sci. 149, 103-106) [GPX4, NFE2L2 (oxidative stress); SCN9A (sodium ion binding); EPSTI1 (tissue remodelling); IGFBP3 (insulin-like growth factor binding); TDGF1 (BMP signalling pathway); AGR3 (regulation of ciliary beating)] was assessed by RT-qPCR. H2A.Z and ACTG1 were used as housekeeping genes. Statistical analysis was assessed by ANOVA. The BOEC responded to the presence of 2-cell embryos only when in direct contact by significantly decreasing abundance of NFE2L2. Both direct and indirect embryo contact or culture with CM significantly decreased GPX4, ROCK2, and SCN9A transcripts compared with control. The presence of 2-cell embryos irrespective of being in direct or indirect contact reduced the expression of SMAD6 compared with the control and CM groups. In the case of CM, expression of IGFBP3 was enhanced compared with the control but was similar to the presence of the 2-cell embryos. In the presence of 8-cell embryos, direct contact with BOEC significantly down-regulated the expression for GPX4 and SOCS3, whereas expression of SCN9A was up-regulated. The opposite was observed when compared with control. The presence of 8-cell embryos down-regulated the expression of SMAD6 and ROCK2 compared with the CM group, whereas direct or indirect contact with BOEC or culture with CM down-regulated the expression of PRELP compared to control. In conclusion, these results provide evidence for a differential affect on the transcriptome of BOEC in vitro depending on embryo stage. These changes may be related either with direct embryo contact or embryo secretions released into the media. Research supported by Spanish MINECO-AGL2015-70140-R; AGL2015-66145-R; OECD-Co-operative Programme TAD/CRP JA00092482.

The metabolic syndrome is associated with carotid atherosclerosis and arterial stiffness in asymptomatic, nondiabetic postmenopausal women

The menopause transition is associated with adverse changes in cardiometabolic risk factors. We aimed to examine the association of the metabolic syndrome (MS) and its features with indices of vascular structure and function in a population of asymptomatic postmenopausal women. A total of 473 informed-consenting, nondiabetic postmenopausal women were included in the study. The MS was defined according to the Joint Definition. We evaluated the association between the presence of MS and indices of vascular structure (carotid artery intima-media thickness (IMT); atherosclerotic plaques) and function (flow-mediated dilatation (FMD); pulse wave velocity (PWV)). The mean age of women was 56.4 ± 6.7 and the mean menopausal age was 7.91 ± 6.31. The MS was present in 17.3% of our population. Mean values of PWV increased linearly with the accumulation of features of the MS. IMT was higher in women with the MS compared to women without the MS (0.78 ± 0.12 mm vs. 0.74 ± 0.11, p = .003). Multivariate analysis showed that the presence of the MS was independently associated with common carotid artery IMT (b = 0.149, p = .001), PWV (b = 0.114, p = .012) as well as central systolic and diastolic blood pressure (b = 0.293, p < .001 and b = 0.163, p < .001 respectively). The presence of the MS is associated with subclinical atherosclerosis already in the first postmenopausal decade of this sample of asymptomatic, nondiabetic women. Additional evidence is required to support the causative effect of these associations.

115 In Vivo Transcriptomic Response of Bovine Oviduct Epithelial Cells to the Early Embryo

The presence of a single 8-cell embryo does not alter the transcriptome of the cells of the oviducal isthmus, although a local effect at the precise position of the embryo cannot be ruled out. Thus, we aimed to study the local embryo effect on the transcriptomic response of the epithelial cells of the oviduct in vivo. Fifteen heifers were synchronized and all showed standing heat and were artificially inseminated. All heifers were slaughtered on Day 2.5 after oestrus. The oviducts from 13 animals (with a corpus luteum, CL) were isolated, trimmed free of tissue and divided between ampulla and isthmus. The ipsilateral isthmus was then divided into smaller sections (2 cm). Each section was sequentially flushed until the embryo was located and was then opened and scraped longitudinally to obtain the epithelial cells. Cells were snap-frozen in LN2 for gene expression analysis. All recovered embryos were found at the beginning of the isthmus of the oviduct ipsilateral to the CL. Three at 2-cell stage and 1 at 8-cell stage. The recovery rate was 30.8% (4/13) and only samples from these 4 animals were used for analysis. The 2-cm sections selected for the transcriptomic analysis were embryo section (ES), in which the embryo was found; proximal section (PS), through which the embryo had passed; distal section (DS), on the uterine side of the embryo; and contralateral section (CS), section from the contralateral isthmus. The expression pattern of 10 differentially expressed genes between the isthmus of pregnant and cyclic heifers (Maillo et al. 2015 Biol Reprod. 92, 144) were assessed by RTq-PCR relative to 2 housekeeping genes, H2A.Z and ACTG. Five up-regulated genes (STK32A, SLC26A3, KERA, QRFPR, MCTP1) and 5 down-regulated (SOD3, PRELP, VAT1L, SOCS3, CCL20) were analysed. One-way ANOVA and t-test was used for statistical analysis. Comparison between ES and the CS revealed one significantly altered gene (VAT1L). This is in agreement with our in vivo results in which VAT1L was also down-regulated in the presence of embryos. Comparison within the ipsilateral oviduct of ES and PS samples revealed STK32A, SLC26A3, QRFPR, MCTP1, and SOCS3 transcripts significantly down-regulated compared with DS samples, whereas the expression for CCL20 was different between ES and DS but similar to the PS. In conclusion, the fact that 5 out of 10 transcripts were different between the segment where the embryo was collected and other locations in the oviduct suggests the presence of embryo site-specific signal. However, comparison between the ipsilateral embryo site with the contralateral site revealed that only one transcript was different. Moreover, the similarities in the ipsilateral oviduct between embryo and proximal site may be due to the passage of the embryo. Furthermore, the location of the embryo close to the ampullary-isthmic junction may mask the effect due to the spatial differences of the bovine oviduct. Research supported by EU, Horizon 2020 Marie Sklodowska-Curie, REPBIOTECH 675526; Spanish MINECO AGL2015-70140-R & AGL2015-66145-R; OECD-CoOperative Prog TAD/CRP JA00092482.

Correlation of serum anti-Müllerian hormone levels with positive in vitro fertilization outcome using a short agonist protocol

OBJECTIVE

We examined the predictive ability of anti-Müllerian hormone (AMH) for clinical pregnancy in women who underwent in vitro fertilization (IVF) cycles in a short agonist protocol.

DESIGN

This is a retrospective cohort study of 222 women undergoing their first IVF attempt between June 2010 and March 2016. Multivariate logistic regression analysis was performed to evaluate the independent associations between clinical pregnancy and its possible predictors.

RESULTS

14.9% of cycles were cancelled, >3 oocytes were retrieved in 55.4% of cycles and embryo transfer was performed in 70.7% of cases. Live birth was the final outcome in 19.8% of subjects, miscarriage occurred in 4.1%, whereas no pregnancy occurred in the remaining 76.1% of the study sample. The number of oocytes, number of embryos, embryo transfer rate and pregnancy rates were positively associated with serum AMH concentrations (p <0.001, for each association). When analyzed by age quartiles, the overall association between AMH and clinical pregnancy rates was evident across all age strata.

CONCLUSIONS

Serum AMH levels are a strong predictive marker of clinical pregnancy in women undergoing a short agonist IVF protocol. There is also a strong association with cancellation rate, number of oocytes retrieved, poor response (≤3 oocytes), number of embryos, embryo transfer rate and live birth rates.