Is copeptin a new potential biomarker of insulin resistance in polycystic ovary syndrome?

O: BJECTIVES: Copeptin has been reported to play an important role in metabolic response in women with PCOS. However, the optimal cut-off value for detecting subjects with insulin resistance (IR) remains undetermined. We investigated whether copeptin can serve as an indicator of IR and tried to determine the optimal cut-off value of plasma copeptin concentration in detecting subjects with PCOS and IR. MATERIAL AND METHODS: We carried out a case-control study on 158 women with PCOS and HOMA-IR < 2.5, 96 women with PCOS with HOMA-IR ≥ 2.5, and 70 healthy volunteers. Plasma copeptin, as well as hormonal, biochemical, metabolic, and IR parameters, were measured. To investigate whether copeptin allows IR to be predicted in PCOS, we used logistic regression models and ROC curve analysis. RESULTS: Median plasma copeptin concentration was the highest in the women with PCOS and HOMA-IR ≥ 2.5. Logistic regression analysis revealed that copeptin was the strongest predictor of HOMA ≥ 2.5 (OR: 53.34 CI 7.94-358.23, p < 0.01). Analysis of ROC curves indicated that the cut-off value above 4 pmol/L of plasma copeptin concentration had high (99%) specificity but very low (21%) sensitivity in diagnosing of IR (AUC 0.607 (95% CI 0.53-0.68. CONCLUSIONS: Our findings suggest that copeptin is associated with IR in PCOS patients, but due to low sensitivity should not be considered as a marker of IR.

The effect of human sperm chromatin maturity on ICSI outcomes.

Because sperm chromatin may play a key role in reproductive success, we verify the associations between sperm chromatin abnormalities, embryo development and the ability to achieve pregnancy. The evaluation of sperm chromatin maturity using aniline blue (AB), chromomycin A3 (CMA3) and toluidine blue (TB) staining were carried out in group of males from infertile couples that underwent ICSI. Low levels of sperm chromatin abnormalities (< 16%) were found in most subjects (> 50%). A higher percentage of TB-positive sperm cells were discovered in the men from couples who achieved ≤ 50% fertilized oocytes compared to men who achieved > 50%. No significant differences were discovered by the applied tests between the men from couples who achieved ≤ 50% and those who achieved > 50% high-quality embryos on the 3rd or 5th day after fertilization, nor between the men from couples who achieved pregnancy and those who failed. The sperm chromatin maturity did not correlate with the ICSI results. However, the ROC analysis revealed a significant predictive value of TB-positive spermatozoa only for fertilization. Therefore, the TB assay can be considered as a useful test for the prediction of fertilization. Our findings suggest that the level of sperm chromatin abnormalities of the examined men was not clinically significant. No found associations between sperm chromatin maturity and embryo development and the ability to achieve pregnancy. We could not exclude the effects of the repairing processes in the fertilized oocyte. The use of complementary tests that verify the status of the sperm chromatin seems justified.

Reproductive outcomes of intracytoplasmic sperm injection (ICSI) in good-prognosis patients who electively decided to limit the number of oocytes used for microinjection: a two-center comparative study.

OBJECTIVES: The aim of the study was to compare the outcomes of intracytoplasmic sperm injection/embryo transfer (ICSI/ET) between two IVF centers with similar pregnancy rates and embryo transfer policy but with two different approaches to good-prognosis patients who intentionally chose to limit the number of oocytes used for ICSI. MATERIAL AND METHODS: It was a retrospective two-center comparative study A total of 218 patients after successful retrieval of >10 mature oocytes following ovarian hyperstimulation were included in the study The number of fertilized oocytes used during ICSI/ET was limited to 6 and 10 in 108 and 110 patients of the Centre for Reproductive Medicine KRIOBANK and VitroLive Fertility Clinic, respectively RESULTS: No significant differences in the implantation rate (29.93% vs. 29.54%; p=0.94) and ongoing pregnancy rate (39.81% vs. 45.45%, p=0.40) were observed between patients who electively fertilized 6 as compared to 10 oocytes, respectively However in patients who deliberately limited the number of fertilized oocytes to 6 the following were observed: i) significantly fewer embryos available for ET (2.89 ± 1.23 vs. 3.77 ± 1.48, p<0.0 1); ii) considerably lower number of frozen embryos per cycle (1.05 ± 1.30 vs. 2.00 ± 1.67, p<0.01), and iii) lower rates of cycles with embryo cryopreservation (4 7.22% vs. 72.72%, p<0.01) as compared to patients with 10 fertilized oocytes. CONCLUSIONS: Elective fertilization of 6 vs. 10 oocytes does not adversely affect fresh ICSI/ET outcome in normal-responding patients. Restricted number of oocytes used for ICSI/ET may be a favorable alternative for couples who do not wish to cryopreserve surplus human embryos.

TGFß3 (TGFB3) polymorphism is associated with male infertility.

Factors affecting the blood-testis barrier function may be involved in testicular damage and male infertility. Two cytokines play an important role in the barrier regulation, namely transforming growth factor beta 3 (TGF-ß3) and tumor necrosis factor (TNF-α). The aim of this study was to investigate the potential association between TGF-ß3 (TGFB3) and TNF-α (TNF) gene polymorphisms and male infertility. A total of 846 subjects, 423 diagnosed with male infertility and 423 fertile men were enrolled. TGFB3 (rs2268626:T > C, rs3917158:C > T, rs2284792:A > G, rs2268625:T > C, rs3917187:C > T) and TNF (rs1800629:-308G > A) gene polymorphisms were genotyped. No association between TNF genotype and infertility was observed. As for TGFB3, the genotypes distribution was similar in infertile and fertile men. However, rs2284792 minor allele frequency was significantly higher among infertile subjects. Heterozygous rs2284792 AG genotype was associated with increased odds for infertility [OR = 1.40 (95% CI 1.05-1.86), p = 0.021] and similar results were observed for G allele carrier status [OR = 1.40 (95% CI 1.06-1.84), p = 0.017]. Heterozygosity in TGFB3 rs3917158 was also associated with the infertility [OR = 1.37 (95% CI 1.01-1.87), p = 0.041]. The TGFB3 variant genotypes were associated with lower spermatozoa motility parameters in fertile men. The results indicate that variants in TGFB3 gene may be associated with male infertility. However, the findings require further replication and validation.

Organic cation/carnitine transporter OCTN2 (SLC22A5) -207C>G (rs2631367) polymorphism is not associated with male infertility.

Carnitine is an important factor in the initiation of progressive sperm motility and end stage of sperm maturation. The compound is transported by an organic cation/carnitine transporter (OCTN2), which is expressed in the male reproductive system. OCTN2 is encoded by SLC22A5 gene with proven -207C>G functional polymorphism. The aim of the case-control study was to investigate a potential association between the -207C>G SLC22A5 polymorphism and male infertility. The -207C>G SLC22A5 polymorphism was determined by means of TaqMan assay in 206 infertile Caucasian males and 256 ethnically matched controls. Besides genotyping study, sperm mitochondrial function was assessed using NADH-dependent NBT assay. The distribution of SLC22A5 genotypes in infertile men was as follows: CC - 29.6%, CG - 53.9%, GG - 16.5% and in fertile men: CC - 32.0%, CG - 50.0%, GG - 18.0%, and was comparable in both evaluated groups. Likewise, the studied polymorphism did not affect sperm mitochondrial function. The results of the current study demonstrated that -207C>G polymorphism of the SLC22A5 gene is not associated with male infertility.

Association study of folate-related enzymes (MTHFR, MTR, MTRR) genetic variants with non-obstructive male infertility in a Polish population.

Spermatogenesis is a process where an important contribution of genes involved in folate-mediated one-carbon metabolism is observed. The aim of the present study was to investigate the association between male infertility and the MTHFR (677C > T; 1298A > C), MTR (2756A > G) and MTRR (66A > G) polymorphisms in a Polish population. No significant differences in genotype or allele frequencies were detected between the groups of 284 infertile men and of 352 fertile controls. These results demonstrate that common polymorphisms in folate pathway genes are not major risk factors for non-obstructive male infertility in the Polish population.

Arachidonic and linoleic acid derivatives impact oocyte ICSI fertilization--a prospective analysis of follicular fluid and a matched oocyte in a 'one follicle--one retrieved oocyte--one resulting embryo' investigational setting.

OBJECTIVE: To evaluate human oocyte ability to undergo fertilization and subsequent preimplantation embryonic development in relation to a wide panel of follicular fluid (FF) arachidonic acid derivatives (AAD) and linoleic acid derivatives (LAD) of prospectively selected patients undergoing intracytoplasmic sperm injection (ICSI). METHODOLOGY: Study was designed as a two center (a university clinic and a private clinic) prospective study. 54 women of 181 consecutive couples undergoing ICSI were prospectively found to be eligible for analysis. 'One follicle - one retrieved oocyte - one resulting embryo' approach was used. Each individual follicle was aspirated independently and matched to an oocyte growing in this particular follicular milieu. FF samples were assessed for AAD and LAD by high-performance liquid chromatography; additionally, activity of secretory phospholipase A (sPLA2) was determined by enzyme-linked immunosorbent assay. PRINCIPAL FINDINGS: Increased activity of sPLA2 and significantly higher AAD and LAD levels were found in FF of oocytes that did not show two pronuclei or underwent degeneration after ICSI in comparison to oocytes with the appearance of two pronuclei. Receiver operating characteristics curve analysis identified acids with the highest sensitivity and specificity: 5oxo-hydroxyeicosatetraenoic, 16-hydroxyeicosatetraenoic, 9-hydroxyoctadecadieneoic and 12-hydroxyeicosatetraenoic. No significant differences between AAD and LAD related to embryo quality were found. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates for the first time that elevated concentrations of AAD and LAD in FF at the time of oocyte retrieval significantly decrease the ability of oocytes to form pronuclei after ICSI. This may serve as a new tool for non-invasive assessment of oocyte developmental capacity. However, levels of AAD and LAD are not associated with subsequent embryo quality or pregnancy rate, and therefore more studies are needed to determine their usefulness in human IVF procedure.

Novel morphological findings of human sperm removal by leukocytes in in vivo and in vitro conditions: preliminary study.

PROBLEM: Biological significance of increased number of leukocytes in ejaculate remains a subject of controversy. The aim of this research was to describe the morphological characteristics of the sperm elimination by leukocytes in in vivo and in vitro conditions using natural stimulator of the immune system--uropathogenic Escherichia coli, O75:HNT, isolated from semen. METHOD OF STUDY: The study was performed on ejaculated spermatozoa from normozoospermic men with leukocytospermia (n=10, in vivo experiment) or without leukocytospermia (n=15, in vitro experiment). Morphological observations were performed using light and scanning electron microscopy. RESULTS: Sperm removal by active leukocytes mediated by traditional phagocytosis and generation of extracellular traps were observed in in vivo and in vitro experiments. CONCLUSION: Our morphological data suggest that human germ cells activate leukocytes triggering both traditional phagocytosis and a novel trapping mechanism, followed by extensive sperm elimination.