Assessment of the Role of Nuclear ENDOG Gene and mtDNA Variations on Paternal Mitochondrial Elimination (PME) in Infertile Men: An Experimental Study.

In humans and most animals, maternal inheritance of mitochondria and mitochondrial DNA (mtDNA) is considered as an universal assumption. Recently, several lines of evidence suggest that different species seem to employ distinct mechanisms to prevent the inheritance of paternal mtDNA. There are few studies in the literature on the molecular basis of sperm mtDNA elimination in mammals and paternal mtDNA transmission in humans. Endonuclease G (ENDOG) is a mitochondrial nuclease encoded by nuclear ENDOG gene. The critical importance of ENDOG gene on paternal mitochondrial elimination (PME) has been previously demonstrated in model organisms such as C. elegans and D. melanogaster. However, its mechanism in human is still unclear. Therefore, we aimed to evaluate whether nuclear ENDOG gene copy number could be a potential marker of paternal mtDNA transmission or not.Male factor infertility patients diagnosed with different infertility subgroups such as azoospermia, oligoteratozoospermia, astheno-teratozoospermia were included in this study: 13 infertile men and 25 healthy men as control group. Quantitative real-time polymerase chain reaction (qPCR) analysis and dual-color Fluorescence in situ hybridization (FISH) method were used to compare the groups. FISH method was applied to verify qPCR results and two signals were observed in nearly all patients. ENDOG gene copy number data were evaluated by comparing them with entire human mtDNA next-generation sequencing (NGS) analysis results obtained through bioinformatics and proteomics tools. Mitochondrial whole genome sequencing (WGS) data allowed determination of novel and reported variations such as single nucleotide polymorphisms (SNPs), multiple nucleotide polymorphism (MNP), insertion/deletion (INDEL). Missense variants causing amino acid substitution were filtered out from patients' mtDNA WGS data.Relative copy number of target ENDOG gene in male infertility patients [0.49 (0.31 - 0.77)] was lower than healthy controls [1.00 (0.66 - 1.51)], and statistical results showed significant differences between the groups (p < 0.01). A total of 38 missense variants were detected in the genes encoding the proteins involved in the respiratory chain complex. Moreover, we detected paternal mtDNA transmissions in the children of these patients who applied to assisted reproductive techniques.In conclusion, this study reveals that ENDOG gene may be an important factor for the PME mechanism in humans. To the best of our knowledge, this is the first study in humans about this topic and assessment of ENDOG gene sequencing and gene expression studies in a larger sample size including patients with male factor infertility would be our future project.

The role of the serum exosomal and endometrial microRNAs in recurrent implantation failure.

OBJECTIVE: It has been identified that endometrium specific microRNAs have different expression levels in endometrial tissues and maternal serum during endometrial cycle. The aim of this study was to analyze microRNA expression levels in recurrent implantation failure patients and healthy controls endometrial samples for enlightening the aetiopathogenesis of the disease. The second aim was to search for a potential noninvasive molecular biomarker in early diagnosis and treatment of Recurrent Implantation Failure (RIF) patients. METHODS: Endometrium and serum samples in two different phases (PP; proliferative phase and SP; secretory phase) from the same cases (RIF; n = 12 and Control; n = 8) were obtained. The expression levels of the microRNA by RT-qPCR method were measured. The expression levels of the healthy controls and study group were compared. Lastly performed target genes analysis of significantly dysregulated miRNA by target analyze databases for obtained related biological pathways. RESULTS: This study showed that has-miR-145, has-miR-23b, has-miR-31 and has-miR-30b were significantly up-regulated in PP and down-regulated in SP endometrium samples. In serum samples, has-miR-145 and hsa-miR-23b were significantly down-regulated in both of PP and SP. Target gene and pathway analysis for dysregulated miRNAs identified important, validated and predicted genes for the implantation process. CONCLUSIONS: This study is the first study to obtain endometrium and serum samples in two different phases from the same cases and measure the candidate miRNAs expression. Our finding suggests that expression level of four candidate miRNAs may be involved in RIF development in women. Furthermore, these miRNAs can be potential biomarker for early diagnosis of RIF patients.

Is Endometriosis Telemedicine Friendly?

Objectives: Social isolation and lockdowns made telemedicine to gradually penetrate daily practice. Telemedicine has been used successfully in many areas of medicine such as psychiatry but is new in obstetrics and gynecology. This study aimed to investigate whether a telemedicine model would be feasible in choosing patients who needed face-to-face visits during the pandemic. Materials and Methods: Telephone calls were conducted with patients with endometriosis who were admitted to our endometriosis clinic before the pandemic. The primary outcome was to appropriately triage the patients who could postpone their routine visit without any risk and those who needed an in-clinic appointment. Results: Seventy-nine patients were included in the study. Among 58 patients who could be reached, 55 accepted to participate in the study. The mean length of the telephone calls was 8.17 min. Nine patients required an in-clinic appointment (16.4%), whereas 46 (83.6%) patients were managed with the phone call. Compliance with hormonal agents for the treatment of endometriosis-associated pain was 11/17 (64.7%). The most commonly asked questions by patients were about cervical screening, fertility cryopreservation, and the medical treatment options of endometriosis. Conclusion: Telemedicine visits can never replace in-clinic practice but can help with a considerable degree of efficacy in the management of patients with endometriosis.

Endometrial gene expression profiling of recurrent implantation failure after in vitro fertilization.

Recurrent implantation failure (RIF) is diagnosed when good-quality embryos repeatedly fail to implant after transfer in several in vitro fertilization (IVF) treatment cycles. Different expression profiles in maternal mRNAs could be referring to many diseases including RIF. This study aimed to reveal significantly dysregulated selected genes expression between healthy fertile women and RIF patients in the implantation window days of the natural menstrual cycle. MME, WWC1, TNC, and FOXP3 genes were chosen as target genes regarding their possible relations with the implantation process. Pathways with these genes were identified and the relationship between these pathways and RIF was investigated. In this study, the endometrial biopsy samples were collected in the secretory phase (cycle day 20-24) of the menstrual cycle from RIF patients (n = 34) and healthy fertile controls (n = 34). After "Pathway and network-oriented GWAS analysis" (PANOGA) and "Kyoto Encyclopedia of Genes and Genomes" (KEGG) pathway analysis; "Membrane Metalloendopeptidase" (MME), "WW and C2 Domain Containing 1" (WWC1), "Tenascin C" (TNC) and "Forkhead Box P3" (FOXP3) genes were chosen as target genes by regarding their possible relation with implantation process. Detection of differences in mRNA expressions between the control group and RIF patients has been performed with the droplet digital PCR (ddPCR) method. Results of the study showed that MME and WWC1 genes expression levels are significantly (p < 0,05) up-regulated 4.9 and 5.2 times respectively and TNC gene expression level is significantly (p < 0,05) down-regulated 9 times in the RIF samples compared to the control group. However, no statistically significant difference was observed between the patient group and the control group in the expression of the FOXP3 gene (p < 0.05). Changes are observed in the expression of the renin-angiotensin system pathway in which the MME gene is involved in the implantation process. The increase in MME gene expression can be speculated to cause implantation failure by restricting the invasion of trophoblast cells. Increasing WWC1 gene expression in the Hippo signaling pathway inhibits "Yes-associated protein 1" (YAP) expression, which is a transcriptional cofactor. Inhibition of YAP protein expression may impair the implantation process by causing the failure of endometrial decidualization. The TNC gene is located in the focal adhesion pathway and this pathway reduces cell adhesion on the endometrial surface to facilitate the attachment of the embryo to the endometrium. The reason for implantation failure might be that the intercellular connections are not suitable for implantation as a result of decreased expression of the focal adhesion pathway in which the TNC gene is effective. Considering the relations between the pathways of the target genes and the implantation process, changes in the expression of target genes might be a cause of RIF.

The genomic analysis of endometrial mitochondrial DNA copy number variation on recurrent implantation failure.

OBJECTIVE: Aim of this study was to define the relationship between RIF (Recurrent Implantation Failure) and endometrial mtDNA copy number. STUDY DESIGN: A total of 50 women of reproductive age including twenty-five patients clinically diagnosed with RIF and twenty-five fertile women as healthy controls were recruited into the study. Endometrial biopsy samples were obtained with a pipelle at the 20-24 days of the menstrual cycle of each participant. Total genomic DNA samples were isolated from endometrial tissues; MT-ND1 (mitochondrially encoded NADH dehydrogenase I) and MT-CO2 (mitochondrially encoded cytochrome C oxidase II) target genes were amplified by droplet digital PCR (ddPCR). Nuclear GAPDH (Glyceraldehyde-3-Phosphate Dehydrogenase) gene was also used for study normalization. The study has been conducted between February 2019 and June 2019. RESULT(S): Droplet digital PCR results were analyzed in "QuantaSoft" software. The concentration amount (copies/µl) of each participant's mitochondrial gene was normalized according to the GAPDH gene concentrations as nuclear reference. mtDNA amounts were compared between RIF patients and healthy controls. Normalized data was statistically evaluated using Mann-Whitney U test and ROC curve analysis. CONCLUSION(S): It was concluded that the mitochondrial target gene (MT-ND1 and MT-CO2) copy number amount of RIF patients was higher than the one obtained from the healthy group in endometrial tissues. It is thought that higher mtDNA copy number at the RIF group may be related to increased oxidative stress in the endometrium. This stress factors may influence receptivity negatively and cause implantation failure. The receptivity of the endometrium is associated with the number of mtDNA copies and difference can be used as a biomarker for receptivity analysis.

Investigation of human paternal mitochondrial DNA transmission in ART babies whose fathers with male infertility.

OBJECTIVE: To investigate the paternal mitochondrial DNA's effect on assisted reproductive technology (ART) applications and possible paternal mitochondrial DNA transmission in male factor infertility diagnosed fathers. STUDY DESIGN: Study group was designed according to the families all of which applied to assisted reproductive technologies as a result of male infertility. A total of 16 trios (48 mother-father-child samples) which contain 7 newborns and 9 infants born by in vitro fertilization method (IVF-ICSI) were studied using "Illumina, MiSeq" next-generation sequencing platform (Case-parent trio study). The study has been conducted between February 2017 and May 2018. RESULT(S): Sequencing analysis results were investigated on the basis of "mother-father-child", "mother-child" and "father-child" mitochondrial DNA whole genome sequence data, respectively. In 14 "trios" of 16; maternal mitochondrial DNA haplotype were detected for children, the remaining 2 "trios" had different mitochondrial DNA haplotypes when compared to their mother and fathers. Also; "father-child" sharing same genetic variants (SNP ("Single nucleotide polymorphism") / MNP ("Multiple nucleotide polymorphism") / INDEL ("Insertion/Deletion") were found in 8 "trios". In 5 "trios" of 16; 98-99% paternal mitochondrial DNA genome sequence similarity were obtained by alignment of "father-child" mitochondrial DNA genome. CONCLUSION(S): This study is the first whole mitochondrial genome investigation for paternal mitochondrial DNA contribution in human IVF / ICSI applied trio cases. Our findings for paternally derived variants could be the result of intermolecular recombination between maternal and paternal mitochondrial DNA.