AMPK Suppression Due to Obesity Drives Oocyte mtDNA Heteroplasmy via ATF5-POLG Axis

Due to the exclusive maternal transmission, oocyte mitochondrial dysfunction reduces fertility rates, affects embryonic development, and programs offspring to metabolic diseases. However, mitochondrial DNA (mtDNA) are vulnerable to mutations during oocyte maturation, leading to mitochondrial nucleotide variations (mtSNVs) within a single oocyte, referring to mtDNA heteroplasmy. Obesity (OB) accounts for more than 40% of women at the reproductive age in the USA, but little is known about impacts of OB on mtSNVs in mature oocytes. It is found that OB reduces mtDNA content and increases mtSNVs in mature oocytes, which impairs mitochondrial energetic functions and oocyte quality. In mature oocytes, OB suppresses AMPK activity, aligned with an increased binding affinity of the ATF5-POLG protein complex to mutated mtDNA D-loop and protein-coding regions. Similarly, AMPK knockout increases the binding affinity of ATF5-POLG proteins to mutated mtDNA, leading to the replication of heteroplasmic mtDNA and impairing oocyte quality. Consistently, AMPK activation blocks the detrimental impacts of OB by preventing ATF5-POLG protein recruitment, improving oocyte maturation and mitochondrial energetics. Overall, the data uncover key features of AMPK activation in suppressing mtSNVs, and improving mitochondrial biogenesis and oocyte maturation in obese females.

Serum and follicular fluid metabolome and markers of ovarian stimulation

STUDY QUESTION

What metabolic pathways and metabolites in the serum and follicular fluid are associated with peak estradiol levels and the number of mature oocytes?

SUMMARY ANSWER

In the serum metabolome, mostly fatty acid and amino acid pathways were associated with estradiol levels and mature oocytes while in the follicular fluid metabolome, mostly lipid, vitamin, and hormone pathways were associated with peak estradiol levels and mature oocytes.

WHAT IS KNOWN ALREADY

Metabolomics has identified several metabolic pathways and metabolites associated with infertility but limited data are available for ovarian stimulation outcomes.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study of women undergoing IVF from 2009 to 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 125 women undergoing a fresh IVF cycle at a fertility clinic in the Northeast United States who provided a serum and follicular fluid sample. Untargeted metabolomics profiling was conducted using liquid chromatography with high-resolution mass spectrometry in two chromatography columns (C18 and hydrophilic interaction chromatography (HILIC)). The main ovarian stimulation outcomes were peak serum estradiol levels and number of mature oocytes. We utilized adjusted generalized linear regression models to identify significant metabolic features. Models were adjusted for age,BMI, initial infertility diagnosis, and ovarian stimulation protocol. We then conducted pathway analysis using mummichog and metabolite annotation using level-1 evidence.

MAIN RESULTS AND ROLE OF CHANCE

In the serum metabolome, 480 and 850 features were associated with peak estradiol levels in the C18 and HILIC columns, respectively. Additionally, 437 and 538 features were associated with mature oocytes in the C18 and HILIC columns, respectively. In the follicular fluid metabolome, 752 and 929 features were associated with peak estradiol levels in the C18 and HILIC columns, respectively, Additionally, 993 and 986 features were associated with mature oocytes in the C18 and HILIC columns, respectively. The most common pathways associated with peak estradiol included fatty acids (serum and follicular fluid), hormone (follicular fluid), and lipid pathways (follicular fluid). The most common pathways associated with the number of mature oocytes retrieved included amino acids (serum), fatty acids (serum and follicular fluid), hormone (follicular fluid), and vitamin pathways(follicular fluid). The vitamin D3 pathway had the strongest association with both ovarian stimulation outcomes in the follicularfluid. Four and nine metabolites were identified using level-1 evidence (validated identification) in the serum and follicular fluid metabolomes, respectively.

LIMITATIONS, REASONS FOR CAUTION

Our sample was majority White and highly educated and may not be generalizable to thewider population. Additionally, residual confounding is possible and the flushing medium used in the follicular fluid could have diluted our results.

WIDER IMPLICATIONS OF THE FINDINGS

The pathways and metabolites identified by our study provide novel insights into the biologicalmechanisms in the serum and follicular fluid that may underlie follicular and oocyte development, which could potentially be used to improve ovarian stimulation outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the following grants from the National Institute of Environmental Health Sciences (P30-ES019776, R01-ES009718, R01-ES022955, P30-ES000002, R00-ES026648, and T32-ES012870), and National Institute of Diabetes and Digestive and Kidney Diseases (P30DK046200). The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Utility of Blood Markers for Predicting Outcomes of Fertility Preservation in Patients With Breast Cancer

This study aimed to investigate the usability of blood markers for predicting controlled ovarian stimulation (COS) outcomes in patients with breast cancer undergoing fertility preservation (FP). In total, 91 patients with breast cancer who had undergone COS using a letrozole-combined gonadotropin-releasing hormone (GnRH) antagonist protocol before chemotherapy were enrolled retrospectively in a single tertiary hospital. FP outcomes were compared in terms of the mean platelet volume (MPV), MPV/platelet count (PC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR). The cutoff values for obtaining 10 or more mature oocytes as favorable prognoses were obtained for each parameter, and the COS outcomes were compared based on the cutoff values. The optimal cutoff levels for MPV and MPV/PC were 10.15 [sensitivity: 90.0%; specificity: 45.1%; AUC: 0.687; 95% CI (0.563, 0.810)] and 0.41 [sensitivity: 65.0%; specificity: 67.6%; AUC: 0.682; 95% CI (0.568, 0.796)], respectively. The oocyte numbers did not significantly differ with respect to the cutoff values of NLR, PLR, and LMR (p > 0.05). However, the total number of acquired and mature oocytes were significantly lower in the group with MPV<10.15 than in that with MPV≥10.15 (8.0 ± 5.1 vs. 12.6 ± 9.1, p=0.003; 4.0 ± 3.7 vs. 7.3 ± 6.3, p=0.002, respectively). Similarly, considering the cutoff of MPV/PC as 0.41, the low-MPV/PC group showed a significantly lower total oocyte yield than the high-MPV/PC group (9.5 ± 7.1 vs. 13.1 ± 9.1, p=0.048), whereas the number of mature oocytes showed similar patterns with no statistical significance (5.3 ± 5.4 vs. 7.3 ± 6.1, p=0.092). From logistic regression analysis, age, anti-Müllerian hormone (AMH) level, MPV, and MPV/PC≥0.41 were found to be significant factors for the acquisition of 10 or more MII oocytes (p=0.049, OR: 0.850; p<0.001, OR: 1.622; p=0.018, OR: 3.184; p=0.013, OR: 9.251, respectively). MPV or MPV/PC can be a reliable marker for predicting FP outcome in patients with breast cancer. Protocols to acquire more mature oocytes, such as the dual-trigger approach, could be recommended for patients with breast cancer with MPV<10.15. Furthermore, a higher dose of gonadotropins was considered to obtain more oocytes in patients with MPV/PC<0.41.

The Comparison of Fixed and Flexible Progestin Primed Ovarian Stimulation on Mature Oocyte Yield in Women at Risk of Premature Ovarian Insufficiency

While gonadotrophin releasing hormone (GnRH) antagonists have been the standard of pituitary suppression during ovarian stimulation for ART, progestin primed ovarian stimulation (PPOS) has emerged as an alternative. Progestins can be started simultaneously with gonadotrophins (fixed PPOS) or later in the cycle depending on follicle growth (flexible PPOS). However, the flexible and fixed PPOS regimens have not been directly compared as of yet. This was a retrospective cohort study including women with diminished ovarian reserve who underwent oocyte cryopreservation. All women underwent ovarian stimulation with a fixed 300 IU daily dose of FSH. The primary outcome was the number of MII oocyte retrieved per cycle. Secondary outcome measures included the incidence of premature LH surge (>10ng/mL) and number of follicles larger than 14mm on the day of maturation trigger. During the screening period 2 out of 97 cycles were cancelled before oocyte retrieval, one in each group yielding an overall cancelation rate of 2%. Among women who had oocyte retrieval, 65 underwent flexible and 30 fixed PPOS. At baseline women on fixed and flexible PPOS had similar age (mean difference: -2.17 years, 95% CI: -4.46 to 0.11) and serum AMH levels (mean difference: 0.10 ng/mL, 95% CI: -0.24 to 0.47). Slight imbalances between the groups were rectified with propensity score matching using age and AMH levels. The incidence of premature LH surge (RR: 1.47, 95% CI: 0.51 - 5.27, p = 0.50), follicle count larger than 14mm on hCG day (RR: 1.14, 95% CI: 0.93 - 1.42, p = 0.22), number of MII oocytes retrieved (RR: 0.95, 95% CI: 0.79 - 1.15, p = 0.61) were similar between flexible and fixed PPOS. The rate of no oocyte retrieval was same between the groups (0.0% both) but no formal estimation was possible. Flexible and fixed PPOS regimens had no appreciable differences regarding MII oocyte yield and the incidence of premature LH surges. Cycles without oocyte retrieval were rare in both groups and ultrasonographic parameters of gonadotropin response were similar. Our study suggests the performances of either progestin regimen are comparable in this group of women.

What is the effect of the early follicular phase FSH/LH ratio on the number of mature oocytes and embryo development?

Background/aim

Basal level of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and antral follicle count are used as predictors of ovarian reserve before starting ovulation induction. We aimed to investigate the predictor potential of early follicular phase FSH/LH ratio on controlled ovarian hyperstimulation-intracytoplasmic sperm injection (COH-ICSI) cycle outcomes.

Materials and methods

This retrospective cohort study was conducted with 648 COH-ICSI cycles performed between 2012 and 2014. Cycles were classified according to their basal FSH/LH ratio, group 1(G1) = FSH/LH ratio < 2, N = 473 and group 2(G2) = FSH/LH ratio ≥ 2, N = 175. Demographic characteristics and stimulation parameters were evaluated. Retrieved total oocyte count (TOC), mature oocyte count (MOC), transferred embryo number, and pregnancy results were obtained and transferred to computer by SPSS 21.0 programme.

Results

TOC and MOC of G1 were significantly higher than those of G2. The total gonadotrophin doses of G2 were significantly higher than G1. There was no significant difference between groups for transferred embryo number. Pregnancy and live birth rates were similar in both groups.

Conclusion

In our population, increased FSH/LH ratio did not affect the rates of pregnancy and live birth negatively.

Performance of anti-Müllerian hormone (AMH) levels measured by Beckman Coulter Access AMH assay to predict oocyte yield following controlled ovarian stimulation for in vitro fertilization

PURPOSE

We evaluated the performance of anti-Müllerian hormone (AMH) measured by the Beckman Coulter fully automated Access assay to predict oocyte yield following controlled ovarian stimulation (COS) for in vitro fertilization (IVF).

METHODS

The correlation between the Access assay and the pre-mixing method with Generation II ELISA assay (Gen II pre-mix assay) was assessed using 230 blood samples. The relationship of AMH level measured by the Access assay and the actual number of oocytes retrieved following COS was assessed using 3296 IVF cycles. The performances of AMH, follicle stimulating hormone (FSH), and estradiol (E2) in predicting the responses to COS were also evaluated by constructing receiver operating characteristic (ROC) curves.

RESULTS

The AMH levels measured just before oocyte retrieval by the Access assay and the number of oocytes retrieved following COS showed a good correlation with R = 0.655. The ROC analysis revealed that the sensitivity of AMH was comparable with or lower than that of E2 but higher than that of FSH.

CONCLUSIONS

With the improved Access AMH assays, AMH was as sensitive as E2 and could become an accurate marker of ovarian response to COS in more than 3000 Japanese IVF patients.

Pregnancy and neonatal outcomes of small follicle-derived blastocyst transfer in modified natural cycle in vitro fertilization

OBJECTIVE

To compare the efficacy and safety of blastocyst transfer derived from small follicles (SF; ≤10 mm) and large follicles (LF; ≥11 mm).

DESIGN

Retrospective cohort study.

SETTING

Private clinic.

PATIENT(S)

Patients (n = 1,072) 30-40 years old who underwent blastocyst transfer (BT; n = 1,247) between January 2012 and December 2014.

INTERVENTION(S)

Oocytes retrieved during a modified natural cycle from both LF and SF were fertilized by a conventional method or intracytoplasmic sperm injection. The blastocysts were frozen, thawed, and transferred one by one in the following spontaneous ovulatory cycles or hormone replacement cycles.

MAIN OUTCOME MEASURE(S)

BT resulted in live births and major congenital anomalies.

RESULT(S)

SF-derived BTs (n = 597) yielded 55 chemical abortions (9.2%), 73 clinical abortions (12.2%), and 261 live births (43.8%), whereas LF-derived BTs (n = 650) yielded 71 chemical abortions (10.9%), 73 clinical abortions (11.2%), and 311 live births (47.9%). These incidences were not statistically different between SF- and LF-derived BTs. The incidence of abnormal karyotypes was also not statistically different between SF- and LF-derived spontaneous abortions (71% [39/55] vs. 72% [40/55], respectively). The incidence of major congenital anomalies in neonates did not differ between SF- and LF-derived pregnancies (1.5% and 1.3%, respectively; relative risk = 1.10, 95% confidence interval [0.55-3.21]).

CONCLUSION(S)

SF-derived BT is as efficacious and safe as LF-derived BT.

Follicle Size on Day of Trigger Most Likely to Yield a Mature Oocyte

OBJECTIVE

To identify follicle sizes on the day of trigger most likely to yield a mature oocyte following hCG, GnRH agonist (GnRHa), or kisspeptin during IVF treatment.

DESIGN

Retrospective analysis to determine the size of follicles on day of trigger contributing most to the number of mature oocytes retrieved using generalized linear regression and random forest models applied to data from IVF cycles (2014-2017) in which either hCG, GnRHa, or kisspeptin trigger was used.

SETTING

HCG and GnRHa data were collected at My Duc Hospital, Ho Chi Minh City, Vietnam, and kisspeptin data were collected at Hammersmith Hospital, London, UK.

PATIENTS

Four hundred and forty nine women aged 18-38 years with antral follicle counts 4-87 were triggered with hCG (n = 161), GnRHa (n = 165), or kisspeptin (n = 173).

MAIN OUTCOME MEASURE

Follicle sizes on the day of trigger most likely to yield a mature oocyte.

RESULTS

Follicles 12-19 mm on the day of trigger contributed the most to the number of oocytes and mature oocytes retrieved. Comparing the tertile of patients with the highest proportion of follicles on the day of trigger 12-19 mm, with the tertile of patients with the lowest proportion within this size range, revealed increases of 4.7 mature oocytes for hCG (P < 0.0001) and 4.9 mature oocytes for GnRHa triggering (P < 0.01). Using simulated follicle size profiles of patients with 20 follicles on the day of trigger, our model predicts that the number of oocytes retrieved would increase from a mean 9.8 (95% prediction limit 9.3-10.3) to 14.8 (95% prediction limit 13.3-16.3) oocytes due to the difference in follicle size profile alone.

CONCLUSION

Follicles 12-19 mm on the morning of trigger administration were most likely to yield a mature oocyte following hCG, GnRHa, or kisspeptin.

Intra-follicular kisspeptin levels are related to oocyte maturation and gonadal hormones in patients who are undergoing assisted reproductive technology

Purpose

To assess the kisspeptin concentrations in follicular fluid and their relationship with clinical outcomes during assisted reproductive technology.

Methods

Thirty‐nine patients who were aged 24‐40 years and underwent oocyte retrieval for in vitro fertilization/intracytoplasmic sperm injection participated in this study. In 65 follicular fluid samples that had been obtained from 30 patients and their blood samples, the kisspeptin levels were measured in order to investigate the correlations with their gonadal hormone levels. Venous blood samples were collected from 14 patients to investigate their plasma kisspeptin levels across different phases of assisted reproductive technology.

Results

The follicular fluid kisspeptin level was significantly higher than that of the plasma level and was positively associated with the follicular fluid estradiol concentration and with the serum estradiol and number of mature oocytes. In the plasma, the maximum concentration of kisspeptin was observed on the day of ovum pick‐up and on the day of embryo transfer during ovarian stimulation for assisted reproductive technology.

Conclusion

Kisspeptin was present in the follicular fluid and the plasma kisspeptin concentration was affected by ovarian stimulation. Kisspeptin appears to affect oocyte maturation and ovulation.

Ovarian reserve markers and assisted reproductive technique (ART) outcomes in women with advanced endometriosis

BACKGROUND

The role of ovarian reserve markers as predictors of the controlled ovarian stimulation (COS) response in intracytoplasmic sperm injection (ICSI) cycles in women with endometriosis has been much debated. The aim of the present study is to assess the predictability of ovarian reserve markers for the number of mature oocytes (MII) retrieved and to assess the pregnancy rate and live birth rate in women with advanced endometriosis.

METHODS

Two hundred eighty-five infertile women who had laparoscopy followed by a first ICSI cycle were recruited in this prospective study. One hundred ten patients were diagnosed with endometriosis stage III-IV (group 1), and 175 patients had no endometriosis (group II). Sixty-three patients in group 1 had no history of previous endometrioma surgery (group Ia), and 47 patients had a history of previous endometrioma surgery (group Ib).

RESULTS

The number of mature oocytes retrieved was significantly lower in women with advanced endometriosis than in women with no endometriosis. The number of mature oocytes retrieved in women with and without endometriosis was best predicted by antral follicle count (AFC) and age, whereas only AFC was a predictor in women with previous endometrioma surgery (odds ratio: 0.49; 95% confidence interval: 0.13-0.60). Women with endometriosis had a lower rate of live births than the control group, but this difference was not statistically significant; the number of live births was significantly lower in those with previous endometrioma surgery.

CONCLUSIONS

The best predictor of the COS response in ICSI was AFC, followed by age. Women receiving ICSI following surgery for ovarian endometrioma had a poorer clinical outcome and lower rate of live births compared with those with endometriosis but no previous surgery and the control group.

Adding serum estradiol measurements to ultrasound monitoring does not change the yield of mature oocytes in IVF/ICSI

In a non-randomized, comparative prospective study (416 patients) we compared the outcome of IVF/ICSI in two parallel control groups: one in which patients were followed up using combined monitoring (ultrasound plus serum estradiol monitoring, the UHM group) and one in which only ultrasound monitoring was used (the UM group). This study has taken the number of mature oocytes at the moment of egg retrieval as its primary end variable. After adjustment for age, gravidity, antagonist protocol, AMH and infertility diagnosis, the average difference in number of mature oocytes between the UHM group and the UM group was -0.4 (95% CI: -1.7 to 1.0), which met our definition of clinical equivalence (95% CI for the adjusted mean difference between -2 and 2). Larger studies are still needed to evaluate the differences in the live birth rates per cycle and to further confirm that blood sampling definitively has no added value in monitoring ovarian stimulation for IVF/ICSI.

Single-cell expression analysis of BMP15 and GDF9 in mature oocytes and BMPR2 in cumulus cells of women with polycystic ovary syndrome undergoing controlled ovarian hyperstimulation

PURPOSE

To detect expression of bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9) in oocytes, and their receptor type 2 receptor for BMPs (BMPR2) in cumulus cells in women with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization (IVF), and determine if BMPR2, BMP15, and GDF9 expression correlate with hyperandrogenism in FF of PCOS patients.

METHODS

Prospective case-control study. Eighteen MII-oocytes and their respective cumulus cells were obtained from 18 patients with PCOS, and 48 MII-oocytes and cumulus cells (CCs) from 35 controls, both subjected to controlled ovarian hyperstimulation (COH), and follicular fluid (FF) was collected from small (10-14 mm) and large (>18 mm) follicles. RNeasy Micro Kit (Qiagen) was used for RNA extraction and gene expression was quantified in each oocyte individually and in microdissected cumulus cells from cumulus-oocyte complexes retrieved from preovulatory follicles using qRT-PCR. Chemiluminescence and RIA assays were used for hormone assays.

RESULTS

BMP15 and GDF9 expression per oocyte was higher among women with PCOS than the control group. A positive correlation was found between BMPR2 transcripts and hyperandrogenism in FF of PCOS patients. Progesterone values in FF were lower in the PCOS group.

CONCLUSION

We inferred that BMP15 and GDF9 transcript levels increase in mature PCOS oocytes after COH, and might inhibit the progesterone secretion by follicular cells in PCOS follicles, preventing premature luteinization in cumulus cells. BMPR2 expression in PCOS cumulus cells might be regulated by androgens.

Delivery of a healthy newborn using vitrified zygotes that developed from in vitro matured oocytes retrieved from a patient with polycystic ovarian syndrome

The aim of this study is to evaluate vitrified zygotes, which were developed from in vitro matured oocytes that were retrieved from a patient with polycystic ovarian syndrome. Oocyte retrieval was performed on day 15 following withdrawal bleeding. The oocytes were incubated for 24 h in human tissue culture medium (TCM)-199 maturation medium supplemented with 20% filtrated-mixed patients follicle fluid, follicle stimulating hormone (FSH), and human chorionic gonadotropin (hCG). A total of four immature oocytes were collected. Two of the four oocytes (50.0%) developed to the metaphase-II stage and, subsequently, two fertilized oocytes were vitrified at the pronuclear stage because a very thin endometrium was not conducive for transfer. One of the two vitrified zygotes was thawed and developed to a 4-cell cleavage stage embryo within 24 h. Subsequent to the embryo transfer, a healthy newborn was delivered. A successful delivery was ensued by using vitrified zygotes from an anovulatory woman with polycystic ovarian syndrome. (Reprod Med Biol 2003; 2: 87-90).

Successful delivery following cryopreservation of zygotes produced by in vitro matured oocytes retrieved from a woman with polycystic ovarian syndrome-like disease: a case report

PURPOSE

To estimate frozen zygotes, which developed from in vitro matured oocytes retrieved from polycystic ovarian syndrome-like disease.

METHODS

Oocyte retrieval was performed on Day 15 following withdrawal bleeding. The oocytes were incubated for 24 h in TCM-199 maturation medium supplemented with follicle fluid, E2, FSH, and hCG.

RESULTS

A total of 12 immature oocytes were collected. Seven of the 12 oocytes (58.3%) developed to the metaphase-II stage, and subsequently, all seven fertilized oocytes were frozen at the pronuclear stage. The remaining five oocytes failed to develop to the metaphase-II stage after an additional 24 h of incubation. Three of seven cryopreserved oocytes were thawed and developed to 2-8-cell cleaved stage embryos. The first pregnancy failed. However, the second frozen-thawed embryo transfer resulted in the delivery of healthy twins.

CONCLUSIONS

Successful delivery using frozen zygotes from an anovulatory woman with polycystic ovarian syndrome-like disease.