The levels of steroid hormones and cytokines in individual follicles are not associated with the fertilization outcome after intracytoplasmic sperm injection

Resveratrol-βcd inhibited premature ovarian insufficiency progression by regulating granulosa cell autophagy

BACKGROUND

The ovarian environment of premature ovarian insufficiency (POI) patients exhibits immune dysregulation, which leads to excessive secretion of numerous proinflammatory cytokines that affect ovarian function. An abnormal level of macrophage polarization directly or indirectly inhibits the differentiation of ovarian granulosa cells and steroid hormone production, ultimately leading to POI. Resveratrol, as a health supplement, has been widely recognized for its safety. There is a substantial amount of evidence indicating that resveratrol and its analogs possess significant immune-regulatory functions. It has also been reported that resveratrol can effectively inhibit the progression of POI. However, the underlying immunological and molecular mechanisms through which resveratrol inhibits the progression of POI are still unclear.

RESULTS

Our preliminary reports have shown that resveratrol-βcd, the beta-cyclodextrin complex of resveratrol, significantly enhances the stability of resveratrol. Resveratrol-βcd could regulate the dysfunctional immune status of macrophages and T cells in the tumor microenvironment. In this study, we treated busulfan and cyclophosphamide (B/C)-treated mice, which were used as a POI model, with resveratrol-βcd. After resveratrol-βcd treatment, the levels of IL-6 in the ovaries were significantly increased, and the progression of POI was suppressed. IL-6 activated granulosa cells (GCs) through soluble IL-6R (sIL-6R), promoting autophagy in GCs. Resveratrol-βcd and IL-6 had a synergistic effect on enhancing autophagy in GCs and promoting E2 secretion.

CONCLUSIONS

We partially elucidated the immune mechanism by which resveratrol inhibits the progression of POI and the autophagy-regulating function of GCs. This provides a theoretical basis for using resveratrol to prevent POI in future studies and clinical guidance.

IL-6 of follicular fluid and outcome of in vitro fertilization

The quality of an oocyte is influenced by its microenvironment, which includes cumulus cells and follicular fluid, as well as cells of the immune system and their products. The ovarian interleukins, which are secreted by the granulosa cells and other immune cells within the ovaries and follicles, regulate various functions between the cells. IL-6 is a cytokine that is present in the follicular fluid and may affect the quality of oocytes. There are some inconsistencies in the literature regarding the concentration of interleukin 6 in the follicular fluid. The main objective of this study was to examine whether the concentration of interleukin 6 in the follicular fluid affects the outcome of IVF. This study involved 83 patients who underwent IVF. Follicular fluid was used as the biological material for the analysis. Examination of the obtained follicular fluid and collection of oocytes under a stereomicroscope was performed in the embryological laboratory. The concentration of IL-6 in the follicular fluid was analyzed. IVF and ICSI methods were used as the fertilization methods. Pregnancy was confirmed by the positive serum β-hCG level. The software package SPSS 20 was used for statistical data processing. Analysis of the follicular fluid samples showed a correlation between the concentration of IL-6 in the follicular fluid and the outcome of IVF. The concentration of IL-6 in the follicular fluid was higher in patients with confirmed pregnancy (9.55 ± 7.47 ng/ml). Based on our results, we conclude that the concentration of IL-6 affects the outcome of IVF. If the range of IL-6 concentration is between 3,67 ng/ml and 10 ng/ml, we can expect good IVF outcome with vital pregnancy.

The Mechanism of Traditional Chinese Medicine Based on Semi-Targeted Metabolomics to Improve IVF Outcomes in Senile Patients

Objective

To identify the biological function and metabolic pathway of differential metabolites in follicular fluid of senile patients with kidney qi deficiency undergoing in vitro fertilization-embryo transfer (IVF-ET) and observe the effect of kidney-invigorating herbs on IVF outcomes in senile patients.

Methods

A total of 95 women undergoing IVF treatment were recruited and divided into three groups, including 34 cases in the treatment group (the senile patients with kidney qi deficiency after the intervention of Chinese medicine), 31 cases in the experiment group (the senile patients with kidney qi deficiency of no intervention of Chinese medicine), and 30 cases in the control group (young women with infertility due to male factor). The three groups of women were treated with long protocol ovarian hyperstimulation; the treatment group was given Qi-Zi-Yu-Si decoction on the day of HCG downregulation. Their IVF clinical outcomes were observed. The metabolites changes of kidney qi deficiency syndrome were analyzed in follicular fluid metabolomics using liquid chromatography-mass spectrometry (UPLC-MS/MS).

Results

The syndrome score of kidney qi deficiency syndrome in the treatment group was significantly improved after treatment (P < 0.01). Compared with the experiment group, the available embryo rate and implantation rate were increased, and the difference was statistically significant (P < 0.05). Progesterone, indoleacrylic acid, 2-propenyl 1-(1-propenylsulfinyl) propyl disulfide, N-acetyltryptophan, decanoylcarnitine, 20a-dihydroprogesterone, testosterone acetate, eicosatrienoic acid, 1H-indole-3-carboxaldehyde, choline, phosphorylcholine, and tryptophan were downregulated in the treatment group. Through pathway analysis, glycerophospholipid metabolism and steroid hormone biosynthesis were regulated in senile patients with kidney qi deficiency after Qi-Zi-Yu-Si decoction intervention.

Conclusion

Qi-Zi-Yu-Si decoction can effectively improve the IVF outcome and clinical symptoms of senile patients. Follicular fluid metabolites were significantly changed in senile infertile women with kidney qi deficiency, and the mechanism by which kidney-invigorating herbs improve IVF treatment outcomes may be related to glycerophospholipid metabolism and steroid hormone biosynthesis. This study was registered in the Chinese Clinical Trials Registry Platform (ChiCTR1800014422).

Key to Life: Physiological Role and Clinical Implications of Progesterone

The most recent studies of progesterone research provide remarkable insights into the physiological role and clinical importance of this hormone. Although the name progesterone itself means “promoting gestation”, this steroid hormone is far more than a gestational agent. Progesterone is recognized as a key physiological component of not only the menstrual cycle and pregnancy but also as an essential steroidogenic precursor of other gonadal and non-gonadal hormones such as aldosterone, cortisol, estradiol, and testosterone. Based on current findings, progesterone and novel progesterone-based drugs have many important functions, including contraception, treatment of dysfunctional uterine bleeding, immune response, and prevention of cancer. Considering the above, reproduction and life are not possible without progesterone; thus, a better understanding of this essential molecule could enable safe and effective use of this hormone in many clinical conditions.

The "Hitchhiker's Guide to the Galaxy" of Endothelial Dysfunction Markers in Human Fertility

Endothelial dysfunction is an early event in the pathogenesis of atherosclerosis and represents the first step in the pathogenesis of cardiovascular diseases. The evaluation of endothelial health is fundamental in clinical practice and several direct and indirect markers have been suggested so far to identify any alterations in endothelial homeostasis. Alongside the known endothelial role on vascular health, several pieces of evidence have demonstrated that proper endothelial functioning plays a key role in human fertility and reproduction. Therefore, this state-of-the-art review updates the endothelial health markers discriminating between those available for clinical practice or for research purposes and their application in human fertility. Moreover, new molecules potentially helpful to clarify the link between endothelial and reproductive health are evaluated herein.

Investigating apoptotic, inflammatory, and growth markers in poor responders undergoing natural in vitro fertilization cycles: a pilot study

This study investigates follicular fluid (FF) from patients with poor and normal ovarian response undergoing natural assisted reproductive technology cycles. We report about (1) cell-free DNA (cfDNA), which reflects apoptosis; (2) corticotropin-releasing hormone (CRH); (3) interleukin (IL)-15, which reflects inflammation; (4) granulocyte colony-stimulating factor (G-CSF); (5) vascular endothelial growth factor (VEGF); and (6) insulin-like growth factor I (IGF-I), which reflects follicular growth. Forty-four poor responders and 44 normal responders-according to the Bologna criteria-were recruited. FF samples were prepared for cfDNA quantification employing Q-PCR and for CRH, IL-15, G-CSF, VEGF, and IGF-I quantification employing ELISA. Statistically nonsignificant different levels of FF cfDNA, CRH, IL-15, VEGF, and IGF-I were observed. Interestingly, statistically significant higher G-CSF levels were observed in normal responders (302.48 ± 474.36 versus 200.10 ± 426.79 pg/mL, P = 0.003). Lower cfDNA integrity was observed in cycles resulting in clinical pregnancy for both groups (normal: 0.07 ± 0.04 versus 0.25 ± 0.17 ng/μL, P < 0.001; poor: 0.10 ± 0.06 versus 0.26 ± 0.12 ng/μL, P < 0.001). The results predominantly showcase similarities between normal and poor responders pertaining to inflammatory, apoptotic, and growth factors. This may be attributed to the employment of natural cycles in order to exclude controlled ovarian stimulation as a factor-indicating its detrimental effect. As G-CSF levels presented significantly higher in normal responders, its vital role in understanding a compromised ovarian response is highlighted.

LH supplementation of ovarian stimulation protocols influences follicular fluid steroid composition contributing to the improvement of ovarian response in poor responder women

In this prospective study, we evaluated the steroid levels in 111 follicular fluids (FF) collected from 13 women stimulated with FSH monotherapy and 205 FF collected from 28 women stimulated with FSH + LH because of a previous history of hypo-responsiveness to FSH. Steroid levels were measured by HPLC/MS–MS and related to ovarian stimulation protocol, oocyte maturity, fertilization and quality of blastocysts, after individually tracking the fate of all retrieved oocytes. 17-Hydroxy-Progesterone, Androstenedione, Estradiol and Estrone were significantly higher in the FSH + LH protocol. Progesterone, 17-Hydroxy-Progesterone and Estradiol were more expressed in FF yielding a mature oocyte (p < 0.01) in the FSH + LH protocol. FF Progesterone concentration was correlated with the rate of normal fertilization in the FSH protocol. None of the FF steroids measured were associated with blastocyst quality and achievement of pregnancy. Our results indicate that LH supplementation in hypo-responsive women modifies ovarian steroid production, mimicking physiological production better and likely contributing to an improved ovarian response. Employing a correct methodological procedure to evaluate the relationship between FF steroid hormones and assisted reproduction outcomes, our study reveals that some steroids in single follicles may be helpful in predicting oocyte maturity and fertilization.

Interleukin 6 in follicular fluid reduces embryo fragmentation and improves the clinical pregnancy rate

PURPOSE

The aim of this study was to evaluate the role of interleukin 6 in embryo development in the in vitro fertilization cycles.

METHODS

This was a retrospective cohort study. One hundred and three women undergoing in vitro fertilization and embryo transfer due to a tubal factor were included in the study. The follicular fluid IL-6 levels on oocyte retrieval day from each patient were determined by ELISA. The relationships between follicular fluid IL-6 levels and IVF cycle parameters were investigated.

RESULTS

The levels of follicular fluid IL-6 were not affected by the use of drugs for superovulation or by estrogen. In addition, follicular fluid IL-6 levels did not affect the number of oocytes retrieved or the MII oocyte rate. High levels of follicular fluid IL-6 correlated with a significant increase in the rates of clinical pregnancy. Follicular fluid IL-6 levels did not affect the cell number or the blastomere symmetry of day 3 embryos, but it did significantly reduce the embryo fragmentation rate.

CONCLUSIONS

High levels of follicular fluid IL-6 improved the rates of clinical pregnancy and reduce embryo fragmentation.

Concentration of stromal cell-derived factor-1 (SDF-1/CXCL12) in the follicular fluid is associated with blastocyst development

PURPOSE

To study the association between stromal cell-derived factor-1 (SDF-1/CXCL12) and vascular endothelial growth factor (VEGF) concentrations in individual human ovarian follicles and IVF outcomes.

METHODS

Concentrations of SDF-1 and VEGF in 261 follicular fluid samples were measured with enzyme-linked immunosorbent assay. IVF outcome parameters were included in fertilization rate, cleavage rate, embryo morphology on day 3, and blastocyst morphology on day 5.

RESULTS

The follicular concentration of SDF-1 and VEGF was not significantly associated with fertilization and cleavage outcome, and embryo morphology. The rates of full blastocysts and good-quality blastocysts were significantly higher in follicles with an SDF-1 concentration of 275-350 pg/mL than in the follicles with SDF-1 concentrations of <200 and ≥350 pg/mL (P < 0.05). The follicular concentration of VEGF was not associated with the blastocyst morphology.

CONCLUSION

Our findings showed that follicular concentration of SDF-1, and not VEGF, may be a valuable biochemical marker of blastocyst development.

Fertility challenges for women with sickle cell disease

INTRODUCTION

Sickle cell disease (SCD) represents one of the most common monogenic blood disorders worldwide, with an incidence of over 300,000 newborns affected per year. Reproductive challenges for men and women with SCD have been previously reviewed; however, evidence-based strategies to prevent and manage infertility and increase fecundity are lacking in women with SCD, which is one of the most important factors for quality of life. Areas covered: This review article summarizes the known risk factors for infertility, low fecundity, and premature menopause related to SCD. Expert commentary: Women with SCD have unique risk factors that may impact their ability to conceive, including chronic inflammation, oxidative stress, transfusion-related hemochromatosis, and ovarian sickling, causing ischemia and reperfusion injury to the ovary. Contraception is strongly recommended while on hydroxyurea therapy during reproductive years and discontinuing hydroxyurea for family planning and during pregnancy based on teratogenicity in animal studies. Hematopoietic stem cell transplantation (HSCT), the only curative therapy, sometimes involves conditioning regimens containing alkylating agents and total body irradiation that contribute to infertility and premature ovarian failure. Prior to HSCT or gene therapy, we strongly recommend referral to a reproductive endocrinologist to discuss fertility preservation and surrogacy options for all women with SCD.

Oocyte polarized light microscopy, assay of specific follicular fluid metabolites, and gene expression in cumulus cells as different approaches to predict fertilization efficiency after ICSI

BACKGROUND

The complex relationship between oocyte morphology, specific follicular fluid metabolites, gene expression in cumulus granulosa cells, and oocyte competence toward fertilization and embryo development still needs further clarification.

METHODS

Forty-six oocytes retrieved from the largest pre-ovulatory follicle of patients undergoing intra-cytoplasmic sperm injection (ICSI) were considered assessing: (a) oocyte morphological characteristics at polarized light microscopy (PLM), (b) specific follicular fluid (FF) metabolites previously suggested to influence oocyte competence (AMH, markers of redox status and of cytotoxicity), (c) transcription of AMH and AMH type II receptor genes in cumulus cells. Data were analyzed using mono-parametric tests and multivariable logistic analysis in order to correlate morphological and biochemical data with fertilization.

RESULTS

Comparing normally fertilized oocytes (n = 29, F group) with unfertilized (n = 17, nF group) we observed that: (a) the meiotic spindle area and major axis were significantly higher in nF group and in fertilized oocytes undergoing an early embryo development arrest; (b) AMH level in FF was comparable in F and nF groups; (c) the FF of nF group contained significantly higher levels of cytotoxicity (lactate dehydrogenase) and oxidative stress (Cu,Zn-superoxide dismutase, catalase, 4-hydroxynonenal-protein conjugates) markers; (d) cumulus cells of nF group showed significantly higher AMH receptor type II gene expression.

CONCLUSIONS

Taken together, these observations suggest that an excessive cytotoxicity level can alter AMH signal transduction within cumulus cells, in turn leading to partial inhibition of aromatase activity, altered cytoplasmic maturation and increased oxidative stress, factors able to impair oocyte fertilization competence and embryo growth.

KDR gene polymorphisms and idiopathic recurrent spontaneous abortion

OBJECTIVE

Process of angiogenesis is essential for successful gestation. Disruption in this pathway leads to various undesirable consequences in pregnancy such as recurrent spontaneous abortion (RSA). One of the most important genes involved in angiogenesis is kinase-insert domain-containing receptor (KDR). This study aimed to investigate the associations between two single-nucleotide polymorphisms (SNPs) of KDR gene, 1719A > T and 1192G > A, with idiopathic RSA in south-east Iran.

METHODS

A total of 230 women, including 110 women with a history of at least two consecutive spontaneous miscarriages and 120 healthy women were recruited in this study. Genomic DNA was extracted from peripheral blood samples of participants using the Salting out method. The KDR 1719A > T and 1192G > A polymorphisms were genotyped by the standard amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) technique.

RESULTS

For the case group, frequencies of 2.73%, 30% and 67.27% were observed for AA, AT and TT genotypes in1719A > T SNP, respectively, and the genotype frequencies for controls were equal to AA = 3.33%, AT = 32.5% and TT = 64.17%. Distribution of genotypes in 1192G > A SNP in the case group was 79.1%, 19.1% and 1.8% for GG, AG and AA, respectively, whereas the corresponding values for the controls were GG  =  80%, AG  =  20% and AA  =  0. No significant difference was found between the case and control groups based on the frequency of KDR gene polymorphisms with the susceptibility to RSA.

CONCLUSIONS

There is no association between these two SNPs of KDR gene and the susceptibility to RSA in women from south-east Iran.

Leptin and its potential interest in assisted reproduction cycles

BACKGROUND

Leptin, an adipose hormone, has been shown to control energy homeostasis and food intake, and exert many actions on female reproductive function. Consequently, this adipokine is a pivotal factor in studies conducted on animal models and humans to decipher the mechanisms behind the infertility often observed in obese women.

METHODS

A systematic PubMed search was conducted on all articles, published up to January 2015 and related to leptin and its actions on energy balance and reproduction, using the following key words: leptin, reproduction, infertility, IVF and controlled ovarian stimulation. The available literature was reviewed in order to provide an overview of the current knowledge on the physiological roles of leptin, its involvement in female reproductive function and its potential interest as a prognostic marker in IVF cycles.

RESULTS

Animal and human studies show that leptin communicates nutritional status to the central nervous system and emerging evidence has demonstrated that leptin is involved in the control of reproductive functions by acting both directly on the ovaries and indirectly on the central nervous system. With respect to the clinical use of leptin as a biomarker in IVF cycles, a systematic review of the literature suggested its potential interest as a predictor of IVF outcome, as high serum and/or follicular fluid leptin concentrations have correlated negatively with cycle outcome. However, these preliminary results remain to be confirmed.

CONCLUSION

Leptin regulates energy balance and female reproductive function, mainly through its action on hypothalamic-pituitary-ovarian function, whose molecular and cellular aspects are progressively being deciphered. Preliminary studies evaluating leptin as a biomarker in human IVF seem promising but need further confirmation.

Variability between the follicular steroid hormone levels in different follicles of the same patient and between patients

CONTEXT

There is disagreement as to whether the concentration of a substance in follicular fluid is related to the quality of the follicle as a possible reflection of the oocyte quality or whether this concentration is related to the clinical characteristics of the patient.

AIM

To establish the variability of steroid hormone levels in follicular fluids from different follicles of the same patient and between patients.

SETTINGS AND DESIGN

Prospective cohort study.

MATERIALS AND METHODS

In 31 patients who underwent intracytoplasmic sperm injection it was performed an ultrasound guided aspiration of follicular fluid of the first two mature follicles from each ovary. Chemiluminescent microparticle immunoassays were performed to determine the levels of estradiol, progesterone, testosterone, and dehydroepiandrosterone sulfate (DHEA-S).

STATISTICAL ANALYSIS

Unconditional mixed model.

RESULTS

Variation in estradiol levels between follicles in the same patient was approximately twice the variation between subjects (P = 0.05). In the case of progesterone, the intra-subject variation was similar to the inter-subject variation (P = 0.006). The testosterone levels had a slightly smaller intra-subject variation than inter-subject variation (P = 0.002), and the intra-subject variation in DHEA-S levels was approximately one-fifth of the inter-subject variation (P = 0.0003).

CONCLUSIONS

The variations in the levels of follicular progesterone and testosterone were similar between patients and between a given patient's follicles; however, the estradiol levels variability was higher among different follicles. The amount of follicular estradiol may be considered a selection tool between the follicles of a given patient.

Follicular steroid hormones as markers of oocyte quality and oocyte development potential

CONTEXT:

Various components of follicular fluid are suggested as biochemical predictors of oocyte quality. Previous studies of follicular steroid hormone levels have shown disparate results when related with fertilization outcomes.

AIM:

The objective of the study was to relate the levels of steroid hormones of each individual follicle with oocyte maturation, fertilization results, embryo quality, and pregnancy rates.

SETTINGS AND DESIGN:

Prospective cohort study in a university hospital.

METHODS:

In 31 patients, who underwent intracytoplasmic sperm injection, it was performed an ultrasound guided aspiration of follicular fluid of the first two mature follicles from each ovary. Follicular levels of estradiol, progesterone, testosterone, and dehydroepiandrosterone sulfate were measured by chemiluminescent immunoassay.

STATISTICAL ANALYSIS:

Generalized estimating equation model.

RESULTS:

In follicular fluids with mature oocyte presence, in normal as well as in failed fertilization, there was a positive correlation between follicular testosterone and progesterone (r = 0.794, P = 0.0001 and r = 0.829, P = 0.0001). Progesterone levels were higher in cases of normal fertilization compared to failed fertilization (P = 0.003). B quality embryos came from oocytes immersed in follicular fluids with higher estradiol values and higher estradiol/progesterone and estradiol/testosterone ratios than those of C quality (P = 0.01; P = 0.0009; P = 0.001). Estradiol levels were higher in patients who achieved pregnancy (P = 0.02).

CONCLUSION:

The analysis of follicular hormone composition could be considered as an additional tool in oocyte selection.

The Impact of Infertility on the Psychological Well-Being, Marital Relationships, Sexual Relationships, and Quality of Life of Couples: A Systematic Review

The purpose of this systematic review was to identify, with supporting evidence, the effect of infertility on couples. MEDLINE, PsycINFO, and CINHAL Plus articles were searched for relevant studies (2000-2014) published in English. Twenty articles were included in this review. The results showed that infertility affected couples in the following four aspects of their life: psychological well-being, marital relationships, sexual relationships, and quality of life. There is evidence that infertility has a negative effect on the psychological well-being and sexual relationships of couples, but the evidence is inconclusive for the effect on marital relationships and quality of life.

Metabolite Profiling in the Pursuit of Biomarkers for IVF Outcome: The Case for Metabolomics Studies

Background. This paper presents the literature on biomarkers of in vitro fertilisation (IVF) outcome, demonstrating the progression of these studies towards metabolite profiling, specifically metabolomics. The need for more, and improved, metabolomics studies in the field of assisted conception is discussed. Methods. Searches were performed on ISI Web of Knowledge SM for literature associated with biomarkers of oocyte and embryo quality, and biomarkers of IVF outcome in embryo culture medium, follicular fluid (FF), and blood plasma in female mammals. Results. Metabolomics in the field of female reproduction is still in its infancy. Metabolomics investigations of embryo culture medium for embryo selection have been the most common, but only within the last five years. Only in 2012 has the first metabolomics investigation of FF for biomarkers of oocyte quality been reported. The only metabolomics studies of human blood plasma in this context have been aimed at identifying women with polycystic ovary syndrome (PCOS). Conclusions. Metabolomics is becoming more established in the field of assisted conception, but the studies performed so far have been preliminary and not all potential applications have yet been explored. With further improved metabolomics studies, the possibility of identifying a method for predicting IVF outcome may become a reality.

Low follicular fluid IL-6 levels in IVF patients are associated with increased likelihood of clinical pregnancy

PURPOSE

Relationships between follicular fluid levels of IL-6 with ovarian response and clinical pregnancy were evaluated in IVF-ET cycles.

METHODS

Follicular fluid was collected from ovarian follicles ≥ 14 mm, pooled for each patient, and IL-6 levels were assessed using ELISA (n = 68). Relationships between IL-6 levels and IVF cycle parameters were assessed using nonparametric tests, and between IL-6 levels and clinical pregnancy using multivariable logistic regression analyses.

RESULTS

Significant positive correlations were observed between IL-6 with age (p = 0.035), and IL-6 with estradiol on the day of hCG (p = 0.011). On adjusted analyses, IVF cycles in patients with IL-6 levels <4.0 pg/ml (median value for the group) demonstrated an almost 4-fold increase in likelihood for clinical pregnancy (p = 0.045).

CONCLUSIONS

Lower follicular fluid IL-6 levels in IVF patients are associated with increased likelihood of clinical pregnancy. We hypothesize that endometrial receptivity is a likely target for any deleterious influences of elevated IL-6 levels.

Leptin and ObRa/MEK signalling in mouse oocyte maturation and preimplantation embryo development

Recent studies indicate that LH stimulates production of ovarian paracrine factors that induce meiosis of the oocyte. DNA microarray analyses of ovarian transcripts were performed in mice and major increases of a short isoform of leptin receptor, ObRa, were identified by the preovulatory LH/human chorionic gonadotrophin (HCG) surge. In oocytes, the level of ObRa transcripts was increased shortly after HCG stimulation, whereas the level of ObRb transcripts was not changed. Leptin was produced by cumulus, granulosa, theca and interstitial cells of ovaries and its transcript level was not regulated during gonadotrophin treatment. Treatment with leptin promoted germinal vesicle breakdown (GVBD) in oocytes within preovulatory follicles, and enhance first polar body extrusion in both cumulus-oocyte complexes and denuded oocytes. The leptin-promoted GVBD and first polar body extrusion were blocked by a mitogen-activated protein kinase extracellular signal regulated kinase kinases (MEK)1/2 inhibitor, U0126, but not its inactive analogue U0124. Furthermore, leptin promoted fertilization of oocytes and the in-vitro development of zygotes to preimplantation embryos. These findings suggest paracrine roles of leptin in the enhancement of nuclear maturation of oocytes through MEK1/2 signalling, and in the promotion of cytoplasmic maturation essential for successful oocyte development to the preimplantation embryos.

Follicular fluid steroid hormone levels are associated with fertilization outcome after intracytoplasmic sperm injection

OBJECTIVE

To investigate the association between hormone levels from individual follicles and fertilization outcome among patients undergoing intracytoplasmic sperm injection (ICSI). Differences in concentrations of selected sex steroids and pituitary hormones in individual follicular aspirates between oocytes that fertilize successfully, those that fail to fertilize, and those that degenerate with ICSI were examined.

DESIGN

Prospective cohort study.

SETTING

Academic medical center.

PATIENT(S)

Women undergoing ovarian stimulation and ICSI.

INTERVENTION(S)

Follicular fluid was sampled by transvaginal ultrasound-guided aspiration of the hyperstimulated ovary. Each follicle was individually aspirated and collected. Intracytoplasmic sperm injection and subsequent embryo culture were performed using standard laboratory technique. Follicular fluid gonadotropin and steroid hormone levels were measured by immunoassay.

MAIN OUTCOME MEASURE(S)

Oocyte fertilization outcome with ICSI.

RESULT(S)

Oocytes that fertilized normally came from follicles with higher estradiol (adjusted odds ratio [AOR]=1.28) and testosterone (AOR=1.35) concentrations compared with those that degenerated with ICSI. Oocytes that fertilized normally also came from follicles with higher estradiol (AOR=1.14) and progesterone (AOR=1.09) concentrations compared with those that failed to fertilize.

CONCLUSION(S)

The hormonal profile of the follicular fluid yielding a degenerative egg or an egg that fails to fertilize is different from that resulting in normal fertilization. Higher follicular fluid estradiol may be a marker for oocytes that will fertilize normally with ICSI.

Follicular fluid content and oocyte quality: from single biochemical markers to metabolomics

The assessment of oocyte quality in human in vitro fertilization (IVF) is getting increasing attention from embryologists. Oocyte selection and the identification of the best oocytes, in fact, would help to limit embryo overproduction and to improve the results of oocyte cryostorage programs. Follicular fluid (FF) is easily available during oocyte pick-up and theorically represents an optimal source on non-invasive biochemical predictors of oocyte quality. Unfortunately, however, the studies aiming to find a good molecular predictor of oocyte quality in FF were not able to identify substances that could be used as reliable markers of oocyte competence to fertilization, embryo development and pregnancy. In the last years, a well definite trend toward passing from the research of single molecular markers to more complex techniques that study all metabolites of FF has been observed. The metabolomic approach is a powerful tool to study biochemical predictors of oocyte quality in FF, but its application in this area is still at the beginning. This review provides an overview of the current knowledge about the biochemical predictors of oocyte quality in FF, describing both the results coming from studies on single biochemical markers and those deriving from the most recent studies of metabolomics.

Serum pattern of circulating adipokines throughout the physiological menstrual cycle

This study investigated the serum levels of resistin, adiponectin and leptin during the physiological menstrual cycle. Sixteen women (age: 19-30 years; body mass index: 19.46-24.9) with regular menstrual cycles participated. Fasting blood samples were collected on alternate days throughout a full menstrual cycle. Mean resistin concentrations were slightly higher during the luteal phase (5.30+/-0.23 ng/ml) compared to the follicular (4.68+/-0.07 ng/ml) and midcycle (4.86+/-0.09 ng/ml) phases (p=0.032). Mean leptin concentrations during the follicular phase (18.14+/-0.28 ng/ml) were significantly lower compared to the midcycle (21.79+/-0.29 ng/ml, p=0.006) and luteal phases (23.75+/-0.64 ng/ml, p<0.001). The variation of adiponectin concentrations throughout the menstrual cycle was not significant. According to the results, circulating resistin, likewise leptin concentrations vary significantly during the physiological menstrual cycle presenting with higher values during the luteal phase. This pattern, although its physiological importance is not clear, suggests that resistin, likewise to leptin, may have a role in the regulation of cyclic female reproductive functions. The stable adiponectin concentrations throughout the menstrual cycle indicate that this adipokine probably does not play a considerable role in female reproductive functions.