Meta-analysis of endometrial transcriptome data reveals novel molecular targets for recurrent implantation failure

PURPOSE

Gene expression analysis of the endometrium has been shown to be a useful approach for identifying the molecular signatures and pathways involved in recurrent implantation failure (RIF). Nevertheless, individual studies have limitations in terms of study design, methodology and analysis to detect minor changes in expression levels or identify novel gene signatures associated with RIF.

METHOD

To overcome this, we conducted an in silico meta-analysis of nine studies, the systematic collection and integration of gene expression data, utilizing rigorous selection criteria and statistical techniques to ensure the robustness of our findings.

RESULTS

Our meta-analysis successfully unveiled a meta-signature of 49 genes closely associated with RIF. Of these genes, 38 were upregulated and 11 downregulated in RIF patients' endometrium and believed to participate in key processes like cell differentiation, communication, and adhesion. GADD45A, IGF2, and LIF, known for their roles in implantation, were identified, along with lesser-studied genes like OPRK1, PSIP1, SMCHD1, and SOD2 related to female infertility. Many of these genes are involved in MAPK and PI3K-Akt pathways, indicating their role in inflammation. We also investigated to look for key miRNAs regulating these 49 dysregulated mRNAs as potential diagnostic biomarkers. Along with this, we went to associate protein-protein interactions of 49 genes, and we could recognize one cluster consisting of 11 genes (consisted of 22 nodes and 11 edges) with the highest score (p = 0.001). Finally, we validated some of the genes by qRT-PCR in our samples.

CONCLUSION

In summary, the meta-signature genes hold promise for improving RIF patient identification and facilitating the development of personalized treatment strategies, illuminating the multifaceted nature of this complex condition.

The growth and development conditions in mouse offspring derived from ovarian tissue cryopreservation and orthotopic transplantation

PURPOSE

To investigate the potential development or metabolic risk in offspring derived from mice with transplanted frozen-thawed ovarian tissue.

METHODS

Mice ovaries were intervened by vitrification (group V) and slow-freezing (group S) cryopreservation and orthotopic transplantation. Orthotopic transplantation of fresh ovarian (group F) and natural mating (group C) served as control groups. The fertility restoration and health conditions of generations were assessed by offspring counts, anti-fatigue and motor ability, and organ morphology. The methylation rate and expression level of imprinted genes (IGF2R, H19, SNRPN, and PLAGL1) were used to predict the potential risk of development in transplanted generations.

RESULTS

Both the percentage of normal morphological follicles in different developmental periods and the litter size of receipt mice were comparable in all three transplanted groups. There was no significant difference in offspring mice's birth defects, body weight gain, anti-fatigue ability, or exercise capacity among the four groups. The methylation rate of IGF2R, H19, and PLAGL1 showed a significant variation in cryopreservation groups as compared with control groups, as well as a difference in gene expression. The SNRPN appeared to be stable in methylation status. There were no differences in mRNA expression in all groups.

CONCLUSIONS

The different ovarian tissue cryopreservation methods did not influence either maternal fertility function or offspring growth. However, these technologies could affect the methylation rate and expression level of some development-related imprinting genes in the offspring, which may lead to some indeterminacy risk.

Adult male mice conceived by in vitro fertilization exhibit increased glucocorticoid receptor expression in fat tissue

Prenatal development is highly plastic and readily influenced by the environment. Adverse conditions have been shown to alter organ development and predispose offspring to chronic diseases, including diabetes and hypertension. Notably, it appears that the changes in glucocorticoid hormones or glucocorticoid receptor (GR) levels in peripheral tissues could play a role in the development of chronic diseases. We have previously demonstrated that in vitro fertilization (IVF) and preimplantation embryo culture is associated with growth alterations and glucose intolerance in mice. However, it is unknown if GR signaling is affected in adult IVF offspring. Here we show that GR expression is increased in inbred (C57Bl6/J) and outbred (CF-1× B6D2F1/J) blastocysts following in vitro culture and elevated levels are also present in the adipose tissue of adult male mice. Importantly, genes involved in lipolysis and triglyceride synthesis and responsive to GR were also increased in adipose tissue, indicating that increased GR activates downstream gene pathways. The promoter region of GR, previously reported to be epigenetically modified by perinatal manipulation, showed no changes in DNA methylation status. Our findings demonstrate that IVF results in a long-term change in GR gene expression in a sex- and tissue-specific manner. These changes in adipose tissues may well contribute to the metabolic phenotype in mice conceived by IVF.

Effects of the use of assisted reproduction and high-caloric diet consumption on body weight and cardiovascular health of juvenile mouse offspring

Maternal obesity and the use of assisted reproductive technologies (ART) are two suboptimal developmental environments that can lead to offspring obesity and cardiovascular disease. We hypothesized that these environments independently and synergistically adversely affect the offspring's weight and cardiovascular performance at ~7 weeks of age. Mice were fed either 24% fat and 17.5% high-fructose (HF) corn syrup or maintenance chow (5% fat; low-fat, no-fructose (LF)). Dams were subdivided into no ART and ART groups. ART embryos were cultured in Whitten's medium and transferred into pseudopregnant recipients consuming the same diet as the donor. Offspring were fed the same diet as the mother. Body weights (BW) were measured weekly and mean arterial pressure (MAP) was collected through carotid artery catheterization at killing (55±0.5 days old). Expression of genes involved in cardiovascular remodeling was measured in thoracic aorta using qRT-PCR, and levels of reactive oxygen species (ROS) were measured intracellularly and extracellularly in mesenteric resistance arteries. ART resulted in increased BW at weaning. This effect decreased over time and diet was the predominant determinant of BW by killing. Males had greater MAP than females (P=0.002) and HF consumption was associated with greater MAP regardless of sex (P<0.05). Gene expression was affected by sex (P<0.05) and diet (P<0.1). Lastly, the use of ART resulted in offspring with increased intracellular ROS (P=0.05). In summary, exposure to an obesogenic diet pre- and/or post-natally affects weight, MAP, and gene expression while ART increases oxidative stress in mesenteric resistance arteries of juvenile offspring, no synergistic effects were observed.