The Prediction of IVF Outcomes with Autologous Oocytes and the Optimal MII Oocyte/Embryo Number for Live Birth at Advanced Maternal Age

Background and Objectives: Delayed childbearing in advanced age might be associated with a low prognosis for achieving pregnancy. Therefore, it is important to establish a predictive tool that will optimize the likelihood of a live birth at advanced age. Material and Methods: The retrospective study was conducted at the Ferona Fertility Clinic in Novi Sad (Republic of Serbia), between January 2020 and May 2021. The survey included 491 women aged ≥35 who met the inclusion criteria and who were subjected to an IVF (in vitro fertilization) treatment cycle. Results: The average number of retrieved oocytes, MII (metaphase II) oocytes, and developed embryos significantly decreased in advanced age. Age was also found to have a significant adverse effect on pregnancy and live birth rates. In women aged ≥35, 10/12 MII oocytes or 10/11 embryos are required for reaching an optimal live birth rate/cumulative live birth rate. Optimal CLBR (cumulative live birth rate) per one oocyte was achieved when 9 MII oocyte were retrieved. Conclusions: The study indicates that the cut-off for increased risk is ≥42 year. However, despite low live birth rates, autologous IVF for these women is not futile. An increase in the number of retrieved mature oocytes and a generation of surplus cryopreserved embryos could reinforce LBR (live birth rate) and CLBR. Clinicians should be very cautious in counseling, as autologous IVF may only be applicable to women with good ovarian reserve.

BPA activates EGFR and ERK1/2 through PPARγ to increase expression of steroidogenic acute regulatory protein in human cumulus granulosa cells

Bisphenol A (BPA) negatively affects steroid production in human luteinized granulosa cells (GC). This study was designed to address two important questions: (1) whether BPA exerts the same disruptive effect in human cumulus granulosa cells (hCGC) and (2) to reveal the molecular mechanism underlying the BPA's action on steroidogenesis. We used cultured hCGC since these cells exert the properties of GC from early antral follicles. Results showed that BPA at 100 μM decreased estradiol level and CYP19A1 mRNA, but increased progesterone production, steroidogenic acute regulatory protein (STAR) and peroxisome proliferator-activated receptor gamma (PPARγ) mRNA expression after 48 h. Shorter (6 h) exposure to BPA elevated PPARγ mRNA level in hCGC. Addition of ERK1/2 (U0126), EGFR (AG1478) and PPARγ (GW9662) inhibitors prevented the BPA-induced STAR and PPARγ mRNA expression. Western blot analysis showed that BPA induced a rapid EGFR and ERK1/2 activation. The BPA-induced EGFR phosphorylation was prevented by addition of the PPARγ inhibitor, whereas the BPA-induced ERK1/2 activation was prevented by addition of the EGFR or PPARγ inhibitor. These data show that BPA increases the progesterone and decreases the estradiol biosynthetic pathway in hCGC. Augmentation of the progesterone biosynthetic pathway is mediated through the PPARγ-dependent activation of EGFR and ERK1/2, leading to increased expression of STAR mRNA.

Rosiglitazone increases expression of steroidogenic acute regulatory protein and progesterone production through PPARγ–EGFR–ERK1/2 in human cumulus granulosa cells

The mechanism by which rosiglitazone (ROSI: a thiazolidinedione (TZD)) affects steroid production in undifferentiated human granulosa cells is not known. In this study, cultured human cumulus granulosa cells were exposed to ROSI and pharmacological inhibitors of the extracellular signal-regulated kinase 1/2 (ERK1/2), epidermal growth factor receptor (EGFR) and peroxisome proliferator-activated receptor gamma (PPARγ) signalling pathways. Expression of progesterone biosynthetic enzymes, PPARγ and PPARα, progesterone production and ERK1/2 activation were analysed. After 48h, 30μM ROSI increased STAR, 3βHSD and PPARγ mRNA and elevated progesterone production in human cumulus granulosa cells. Addition of ERK1/2 (U0126), EGFR (AG1478) and PPARγ (GW9662) inhibitors prevented the ROSI-induced STAR mRNA expression and progesterone production after 48h. Inhibition of PPARγ, but not EGFR or ERK1/2, decreased the PPARγ mRNA levels induced by ROSI in human cumulus granulosa cells after 48h. On the other hand, U0126 and GW9662 prevented the ROSI-induced increase in PPARγ transcripts after 6h. Western blot analysis showed that ROSI induced a rapid ERK1/2 activation, which was prevented by inhibition of ERK1/2, EGFR and PPARγ in human cumulus granulosa cells. Overall, these data suggested that PPARγ, EGFR and ERK1/2 were involved in the stimulatory effect of ROSI on STAR expression and progesterone production in undifferentiated human cumulus granulosa cells.