The effect of cult-active medium on pregnancy outcomes after intracytoplasmic sperm injection in azoospermic men: A case-control study

Background: Failed oocyte activation following intracytoplasmic sperm injection (ICSI) as a result of calcium deficiency is a major challenge. Objective: We compared the effect of cult-active medium (CAM) on ICSI outcomes in obstructive azoospermia cases. Materials and Methods: The present study was conducted with 152 ICSI cases, classified into CAM and control groups. The injected oocytes in the control group were cultured in the cleavage medium, while in the artificial oocyte activation group, oocytes were chemically activated through exposure to 200 µL of CAM for 15 min. Fertilization and cleavage rates, quality of embryos, and biochemical pregnancy and live birth rates were assessed in both groups. Results: There were significant differences between the groups in terms of fertilization and cleavage rates after using the CAM in the percutaneous epididymal sperm aspiration (PESA) subgroup (p = 0.05, p ≤ 0.001) and in the testicular sperm extraction subgroup (p = 0.02, p = 0.04), compared to their control groups. Also, the pregnancy rate was significantly higher in the PESA-CAM subgroup (p = 0.03). The PESA-CAM subgroup demonstrated a significant difference in embryo quality after ICSI (p = 0.04). Unsuccessful embryo transfer and abortion were lower in both subgroups compared to the control groups, but this difference was not significant. Surprisingly, live birth rate was higher in the PESA-CAM subgroup (p = 0.03). Conclusion: CAM treatment could improve fertilization and cleavage rates in obstructive azoospermia participants. It had a significant effect on embryo quality, and pregnancy and live birth rates in PESA cases. Key words: Calcium ionophore, Obstructive azoospermia, Fertilization, ICSI.

Is there any effect on imprinted genes H19, PEG3, and SNRPN during AOA?

Assisted oocyte activation (AOA) has been proposed as an effective technique to overcome the problem of impaired fertilization after intracytoplasmic sperm injection (ICSI) but the safety of AOA remains a concern. We aimed to investigate if AOA induces imprinting effects on embryos. We used 13 cleavage embryos, nine blastocysts, and eight placentas from 15 patients. The subjects were divided into six groups by tissue type and with or without AOA. The methylation levels of imprinted genes (H19, paternally expressed gene [PEG3] and small nuclear ribonucleoprotein polypeptide N [SNRPN]) were tested by pyrosequencing. We observed different methylation levels among cleavage embryos. The variability was much more remarkable between cleavage embryos than blastocysts and placenta tissues. The methylation levels were especially higher in SNRPN and lower in the H19 gene in AOA embryos than those without AOA. No significant difference was found either among blastocysts or among placenta tissues regardless of AOA. The methylation levels of the three genes in blastocysts were very similar to those in the placenta. Compared to conventional ICSI, AOA changed imprinting methylation rates at H19 and SNRPN in cleavage embryos but not in the blastocyst stage and placenta. We recommend that blastocyst transfer should be considered for patients undergoing AOA during in vitro fertilization.

Design of novel oocyte activation methods: The role of zinc

Oocyte activation occurs at the time of fertilization and is a series of cellular events initiated by intracellular Ca2+ increases. Consequently, oocytes are alleviated from their arrested state in meiotic metaphase II (MII), allowing for the completion of meiosis. Oocyte activation is also an essential step for somatic cell nuclear transfer (SCNT) and an important tool to overcome clinical infertility. Traditional artificial activation methods aim to mimic the intracellular Ca2+ changes which occur during fertilization. Recent studies emphasize the importance of cytoplasmic Zn2+ on oocyte maturation and the completion of meiosis, thus suggesting artificial oocyte activation approaches that are centered around the concentration of available Zn2+in oocytes. Depletion of intracellular Zn2+ in oocytes with heavy metal chelators leads to successful oocyte activation in the absence of cellular Ca2+ changes, indicating that successful oocyte activation does not always depends on intracellular Ca2+ increases. Current findings lead to new approaches to artificially activate mammalian oocytes by reducing available Zn2+ contents, and the approaches improve the outcome of oocyte activation when combined with existing Ca2+ based oocyte activation methods. Here, we review the important role of Ca2+ and Zn2+ in mammalian oocyte activation and development of novel oocyte activation approaches based on Zn2+ availability.

DNA methylation and gene expression changes in mouse pre- and post-implantation embryos generated by intracytoplasmic sperm injection with artificial oocyte activation

Background The application of artificial oocyte activation (AOA) after intracytoplasmic sperm injection (ICSI) is successful in mitigating fertilization failure problems in assisted reproductive technology (ART). Nevertheless, there is no relevant study to investigate whether AOA procedures increase developmental risk by disturbing subsequent gene expression at different embryonic development stages. Methods We used a mouse model to explore the influence of AOA treatment on pre- and post-implantation events. Firstly, the developmental potential of embryos with or without AOA treatment were assessed by the rates of fertilization and blastocyst formation. Secondly, transcriptome high-throughput sequencing was performed among the three groups (ICSI, ICSI-AOA and dICSI-AOA groups). The hierarchical clustering and Principal Component Analysis (PCA) analysis were used. Subsequently, Igf2r/Airn methylation analysis were detected using methylation-specific PCR sequencing following bisulfite treatment. Finally, birth rate and birth weight were examined following mouse embryo transfer. Results The rates of fertilization and blastocyst formation were significantly lower in oocyte activation-deficient sperm injection group (dICSI group) when compared with the ICSI group (30.8 % vs. 84.4 %, 10.0 % vs. 41.5 %). There were 133 differentially expressed genes (DEGs) between the ICSI-AOA group and ICSI group, and 266 DEGs between the dICSI-AOA group and ICSI group. In addition, the imprinted gene, Igf2r is up regulated in AOA treatment group compared to control group. The Igf2r/Airn imprinted expression model demonstrates that AOA treatment stimulates maternal allele-specific mehtylation spreads at differentially methylated region 2, followed by the initiation of paternal imprinted Airn long non-coding (lnc) RNA, resulting in the up regulated expression of Igf2r. Furthermore, the birth weight of newborn mice originating from AOA group was significantly lower compared to that of ICSI group. The pups born following AOA treatment did not show any other abnormalities during early development. All offspring mated successfully with fertile controls. Conclusions AOA treatment affects imprinted gene Igf2r expression and mehtylation states in mouse pre- and post-implantation embryo, which is regulated by the imprinted Airn. Nevertheless, no significant differences were found in post-natal growth of the pups in the present study. It is hoped that this study could provide valuable insights of AOA technology in assisted reproduction biology.

A 10-Year Perspective on the Utility of Three Adjuvants Often Used in IVF: Growth Hormone, Melatonin and DHEA

Since 2010, numerous studies reported from PIVET, a pioneer IVF facility established over 40 years ago, have explored the use of three adjuvants designed to improve laboratory and clinical outcomes in cases where a poor prognosis has been demonstrated. The adjuvants reported commenced with recombinant growth hormone (rGH), followed by dehydroepiandrosterone (DHEA) after developing a unique troche to avoid the first-pass effect and, subsequently, melatonin. The studies show that rGH is beneficial in the situation where women have poor-quality embryos in the setting of additional poor prognosis factors, such as advanced female age, a very low ovarian reserve, an insulin growth factor profile in the lowest quartile or recurrent implantation failure. The studies also imply that the adjuvants may actually reduce live birth productivity rates if used on women without poor prognosis factors; hence, further studies, which can now be better designed, should be undertaken to explore the notion of underlying adult growth hormone deficiency in some cases as well as the suggestion that DHEA can provide equivalent benefits in some poor prognosis settings. Melatonin showed no suggestive benefits in any of the studies and can be excluded from consideration in this context. Future studies should compare rGH and DHEA with a focus on those women who have poor embryo quality with additional poor prognosis factors. Such trials should be extended to 12 weeks to cover the entire period of oocyte activation.

Ionophore application for artificial oocyte activation and its potential effect on morphokinetics: a sibling oocyte study

Purpose To evaluate whether ionophore application at the oocyte stage changes the morphokinetics of the associated embryos in cases of artificial oocyte activation. Methods In a prospective sibling oocyte approach, 78 ICSI patients with suspected fertilization problems had half of their MII-oocytes treated with a ready-to-use ionophore (calcimycin) immediately following ICSI (study group). Untreated ICSI eggs served as the control group. Primary analyses focused on morphokinetic behavior and the presence of irregular cleavages. The rates of fertilization, utilization, pregnancy, and live birth rate were also evaluated. Results Ionophore-treated oocytes showed a significantly earlier formation of pronuclei (t2PNa) and a better synchronized third cell cycle (s3) (P < .05). The rate of irregular cleavage was unaffected (P > .05). Ionophore treatment significantly improved the overall rates of fertilization (P < .01) and blastocyst utilization (P < .05). Conclusion Ionophore application does not negatively affect cleavage timing nor is it associated with irregular cleavage.

Original Research: Expression Profile of CAPZA3 And TR-KIT Genes in Men with Globozoospermia & Asthenoteratospermia that Undergo ICSI Protocol

Objective(s): Sperm-mediated oocyte activation depends upon suitable expression and assembly of sperm-borne oocyte-activating factors (SOAFs) during spermiogenesis. Several factors have been considered as candidates for oocyte activation in recent years. Globozoospermia is a severe sperm morphology disorder that is a rare type of teratozoospermia with an incidence of 0.1% among infertile individuals. testis-specific genes including CAPZA3 [capping protein (actin filament) muscle Z-line, alpha, which is considered as a nominee for sperm associated oocyte activating factors, an actin-capping protein, controlling actin polymerization during spermiogenesis. They contain a common bidirectional promoter. Another gene TR-KIT (a truncated form of the KIT receptor) which is a major sperm-associated oocyte-activating factor. The objective of this study was to investigate the expression profile of CAPZA3 and TR-KIT mRNA, in men with total globozoospermia, Asthenoteratospermia, and fertile individuals. Materials and Methods: Semen samples were collected from three groups including 25 fertile men, 20 Asthenoteratospermia and 12 Globozoospermia that undergo intra-cytoplasmic sperm injection (ICSI), Expression of CAPZA3 and TR-KIT were assessed by Real time PCR. Results: Individuals with Globozoospermia have presented significantly lower expression of CAPZA3 and TR-KIT mRNA when compared with fertile men. Asthenoteratospermia (male factor) showed significantly lower expression of CAPZA3 mRNA, whereas non-significantly of TR-KIT mRNA. Levels of CAPZA3 and TR-KIT mRNA in the spermatozoa of fertile men were significantly higher than the corresponding values of the globozoospermic and Asthenoteratospermia subjects. Conclusion: Analysis mRNA of CAPZA3 gene maybe assist the researcher to identify individuals with a lack of ability to induce oocyte activation and make them a candidate for artificial oocyte activation and help researcher to identify genetic defects associated with failed fertilization. whereas, mRNA of TR-KIT gene appears inability to induce oocyte activation