Cengiz Karakaya

Vitrified human ovaries have fewer primordial follicles and produce less antimüllerian hormone than slow-frozen ovaries

Slow-freezing and vitrification methods of human ovarian tissue cryopreservation were compared in terms of primordial follicle count and in vitro antimüllerian hormone (AMH) and estradiol production. Compared with fresh and slow-frozen ovaries, vitrified ovaries contained statistically significantly fewer primordial follicles and produced statistically significantly less AMH in vitro. Estradiol production from slow-frozen and vitrified ovaries was similar but statistically significantly lower than from fresh cultured strips.

Poor ovarian response in women undergoing in vitro fertilization is associated with altered microRNA expression in cumulus cells

OBJECTIVE To analyze the association of micro-ribonucleic acid (miRNA) expression with the number of oocytes retrieved, in women undergoing in vitro fertilization (IVF). DESIGN Experimental study. SETTING Academic medical center. PATIENT(S) A total of 189 women undergoing IVF-intracytoplasmic sperm injection (ICSI). INTERVENTION(S) Pooled cumulus cells were collected. MAIN OUTCOME MEASURE(S) Poor responders were identified as patients who produced fewer oocytes than the 25th percentile of their respective age group. MicroRNAs were extracted from cumulus cells, and an miRNA microarray was performed, comparing poor responders (n = 3) to non-poor responders (n = 3). Expression of miR-21-5p (active strand of miR-21) and miR-21-3p was tested in poor responders (n = 21) and non-poor responders (n = 29), using reverse transcription real-time polymerase chain reaction (qRT-PCR). Regulation of miR-21-5p and miR-21-3p, in human granulosa-like tumor (KGN) cells, by estradiol (E2), was tested in vitro. RESULT(S) MicroRNA microarray analysis showed up-regulation of 16 miRNAs and down-regulation of 88 miRNAs in poor responders. Notably, miR-21 was significantly up-regulated 5-fold in poor-responder samples. Analysis using qRT-PCR confirmed that miR-21-5p expression was significantly up-regulated in poor responders, whereas miR-21-3p expression was significantly lower, suggesting that elevated miR-21-5p expression in cumulus cells is not regulated at the pre-miR-21 level in poor responders. Both miR-21-5p and miR-21-3p were increased in KGN cells in response to higher doses of E2; their expression was not affected at lower E2 concentrations. CONCLUSION(S) We found that poor response to IVF is associated with altered miRNA expression in cumulus cells, specifically with elevated expression of miR-21-5p, and that this elevated expression is independent of lower serum E2 levels in poor responders.

A potential novel treatment strategy: inhibition of angiogenesis and inflammation by resveratrol for regression of endometriosis in an experimental rat model

Abstract The aim of our study was to evaluate the effectiveness of resveratrol in experimentally induced endometrial implants in rats through inhibiting angiogenesis and inflammation. Endometrial implants were surgically induced in 24 female Wistar–Albino rats in the first surgery. After confirmation of endometriotic foci in the second surgery, the rats were divided into resveratrol (seven rats), leuprolide acetate (eight rats), and control (seven rats) groups and medicated for 21 d. In the third surgery, the measurements of mean areas and histopathological analysis of endometriotic lesions, VEGF, and MCP-1 measurements in blood and peritoneal fluid samples, and immunohistochemical staining were evaluated. After treatment, significant reductions in mean areas of implants (p < 0.01) and decreased mean histopathological scores of the implants (p < 0.05), mean VEGF-staining scores of endometriotic implants (p = 0.01), and peritoneal fluid levels of VEGF and MCP-1 (p < 0.01, for VEGF and p < 0.01, for MCP-1) were found in the resveratrol and leuprolide acetate groups. Serum VEGF (p = 0.05) and MCP-1 (p = 0.01) levels after treatment were also significantly lower in the resveratrol and leuprolide acetate groups. Resveratrol appears to be a potential novel therapeutic agent in the treatment of endometriosis through inhibiting angiogenesis and inflammation. Further studies are needed to determine the optimum effective dose in humans and to evaluate other effects on reproductive physiology.

Follicle-stimulating hormone receptor (FSHR) alternative skipping of exon 2 or 3 affects ovarian response to FSH.

Genes critical for fertility are highly conserved in mammals. Interspecies DNA sequence variation, resulting in amino acid substitutions and post-transcriptional modifications, including alternative splicing, are a result of evolution and speciation. The mammalian follicle-stimulating hormone receptor (FSHR) gene encodes distinct species-specific forms by alternative splicing. Skipping of exon 2 of the human FSHR was reported in women of North American origin and correlated with low response to ovarian stimulation with exogenous follicle-stimulating hormone (FSH). To determine whether this variant correlated with low response in women of different genetic backgrounds, we performed a blinded retrospective observational study in a Turkish cohort. Ovarian response was determined as low, intermediate or high according to retrieved oocyte numbers after classifying patients in four age groups (<35, 35-37, 38-40, >40). Cumulus cells collected from 96 women undergoing IVF/ICSI following controlled ovarian hyperstimulation revealed four alternatively spliced FSHR products in seven patients (8%): exon 2 deletion in four patients; exon 3 and exons 2 + 3 deletion in one patient each, and a retention of an intron 1 fragment in one patient. In all others (92%) splicing was intact. Alternative skipping of exons 2, 3 or 2 + 3 were exclusive to low responders and was independent of the use of agonist or antagonist. Interestingly, skipping of exon 3 occurs naturally in the ovaries of domestic cats--a good comparative model for human fertility. We tested the signaling potential of human and cat variants after transfection in HEK293 cells and FSH stimulation. None of the splicing variants initiated cAMP signaling despite high FSH doses, unlike full-length proteins. These data substantiate the occurrence of FSHR exon skipping in a subgroup of low responders and suggest that species-specific regulation of FSHR splicing plays diverse roles in mammalian ovarian function.

Human embryonic poly(A) binding protein (EPAB) alternative splicing is differentially regulated in human oocytes and embryos

Oocyte maturation is associated with suppression of transcriptional activity. Consequently, gene expression during oocyte maturation, fertilization and early embryo development, until zygotic genome activation (ZGA) is primarily regulated by translational activation of maternally derived mRNAs. Embryonic poly(A)-binding protein (EPAB) is the predominant poly(A)-binding protein in Xenopus, mouse and human oocytes and early embryos prior to ZGA. EPAB plays a key role in polyadenylation-dependent translational activation of mRNAs by stabilizing polyadenylated mRNAs and by stimulating their translation. Epab-knockout female mice are sterile, fail to generate mature oocytes and display impaired cumulus expansion and ovulation. Consistent with its role during gametogenesis and early embryo development, Xenopus and mouse Epab mRNA is expressed exclusively in oocytes and early embryos, and is undetectable following ZGA or in somatic tissues. Herein, we demonstrate that although EPAB is expressed in human somatic tissues, its transcripts largely consist of an alternatively spliced form lacking the first 58 bp of exon 8, which leads to the formation of a premature stop codon 6 amino acids downstream on exon 8, and omission of the functionally critical poly(A)-binding domain. Moreover, 8-cell and blastocyst stage human embryos also express only the alternatively spliced form of EPAB. On the other hand, the full-length form of EPAB mRNA is exclusively expressed in oocytes. In conclusion, in contrast with the transcriptional regulation in Xenopus and mouse, oocyte- and early embryo-specific expression of EPAB in human is regulated by a post-transcriptional mechanism.

The impact of sperm morphology on the outcome of intrauterine insemination cycles with gonadotropins in unexplained and male subfertility.

OBJECTIVE To determine the impact of sperm morphology on success of intrauterine insemination (IUI) in unexplained and male subfertility. STUDY DESIGN Basal and post-wash normal percentage of sperm with normal morphology was assessed prospectively in 412 couples with 530 IUI cycles who underwent ovarian hyperstimulation with gonadotropins. The primary outcome was live birth per cycle. Receiver operating characteristics (ROC) curves were used to determine the effectiveness of sperm morphology to predict live birth in IUI cycles. RESULTS Normal sperm morphology (%) after preparation was higher in patients with live birth (5.4 ± 4.5 vs 4.3 ± 4.1; respectively, p<.05) in study population. In male subfertile group, normal sperm morphology before and after sperm preparation was higher in patients with live birth (1.3 ± 1.4 vs 0.6 ± 0.9; p<0.001 and 4.6 ± 4.4 vs 1.9 ± 2.2; p<0.01, respectively). However, both basal and post-wash normal sperm morphology (%) were similar in patients with and without live birth in unexplained group. The best cut-off value for normal sperm morphology (%) to predict live birth was 4.5% in male subfertile group with a sensitivity of 50.6% and specificity of 61.7%. CONCLUSION Morphological evaluation is not a reliable parameter alone for predicting pregnancy outcome in unexplained infertility. In male subfertility, post-wash normal sperm morphology percentage higher than 4.5 increases the probability of live birth.

Whole Ovary Cryopreservation

Surgical, technological, and medical advances in cancer treatment have improved the life expectancy, making quality of life issues in cancer survivors more important than ever before. Within this context, fertility loss due to the side effects of the chemotherapeutic agents or involvement of the gonads has become an active area of investigation. Many patients demand restoration of their fertility after a successful struggle with cancer and ask to discuss fertility preservation options. Currently, the most recommended procedure is to discuss fertility preservation options with the patient prior to the cancer therapy and as a multidisciplinary team. Whole ovary cryopreservation, although still controversial, may soon become an integral part of this discussion.

The effect of captopril on endometriotic implants in a rat model

OBJECTIVE To determine the effects of captopril on experimentally induced endometriosis in a rat model. STUDY DESIGN Twenty-four adult, mature female Wistar-Albino rats in which endometriotic implants were induced by transplanting autologous uterine tissue to ectopic sites on the peritoneum. After the endometriotic implants were formed surgically, the 24 rats were randomly divided into three groups. Group 1 (captopril group, eight rats) were given 50 mg kg(-1)d(-1) of oral captopril for 21 d. Group 2 (leuprolide acetate group, eight rats) were given a single 1 mg kg(-1) subcutaneous injection of leuprolide acetate. Group 3 (control) were given no medication and served as controls (eight rats). The surface area of the endometriotic implants and the score of histologic analysis. Also, VEGF and MCP-1 levels in peritoneal fluids and bloods were analyzed. RESULTS At the beginning of the medical treatment, the mean surface areas of the endometriotic implants were comparable in all three groups. At the end of the treatment the mean implant surface area in the captopril group and leuprolide acetate group was less than that in the control group. Mean histopathological examination score for the implants post treatment was lower in the captopril and leuprolide acetate groups. Peritoneal fluids VEGF level in the captopril and leuprolide acetate groups was lower than that in the control group. The post-treatment MCP-1 level was also lower in the captopril and leuprolide acetate groups than in the control group. The serum VEGF and MCP-1 levels post treatment were significantly lower in the captopril and leuprolide acetate groups than in the control group. CONCLUSION Administration of captopril reduced the size and progression of endometriotic lesions in a rat model.