Spectrophotometric absorbance of follicular fluid: a selection criterion

Creatine Metabolism in Female Reproduction, Pregnancy and Newborn Health

Creatine metabolism is an important component of cellular energy homeostasis. Via the creatine kinase circuit, creatine derived from our diet or synthesized endogenously provides spatial and temporal maintenance of intracellular adenosine triphosphate (ATP) production; this is particularly important for cells with high or fluctuating energy demands. The use of this circuit by tissues within the female reproductive system, as well as the placenta and the developing fetus during pregnancy is apparent throughout the literature, with some studies linking perturbations in creatine metabolism to reduced fertility and poor pregnancy outcomes. Maternal dietary creatine supplementation during pregnancy as a safeguard against hypoxia-induced perinatal injury, particularly that of the brain, has also been widely studied in pre-clinical in vitro and small animal models. However, there is still no consensus on whether creatine is essential for successful reproduction. This review consolidates the available literature on creatine metabolism in female reproduction, pregnancy and the early neonatal period. Creatine metabolism is discussed in relation to cellular bioenergetics and de novo synthesis, as well as the potential to use dietary creatine in a reproductive setting. We highlight the apparent knowledge gaps and the research “road forward” to understand, and then utilize, creatine to improve reproductive health and perinatal outcomes.

Estradiol and Progesterone Levels are Related to Redox Status in the Follicular Fluid During in vitro Fertilization

Studies have reported a possible association between the levels of oxidative stress biomarkers in follicular fluid (FF) and infertility treatment outcomes. FF analysis can provide important information about oocyte quality. This study aimed to evaluate the possible correlation between oxidative stress biomarker and intrafollicular hormone levels and clinical and laboratory parameters in women during controlled ovarian stimulation. These women were undergoing in vitro fertilization with intracytoplasmic sperm injection (ICSI).The FF samples were acquired from September 2012 to February 2014 from women undergoing private fertility treatment in Rio de Janeiro, Brazil. A total of 196 women who were undergoing ICSI and had different infertility diagnoses were recruited. The FF from each patient (average patient age of 36.3 ± 4.3 years) was collected following puncture of just one follicle with the largest diameter. After ruling out blood contamination by spectrophotometry, 163 patient samples were utilized in the study. In the FF, the progesterone levels were negatively correlated with (a) hydrogen peroxide scavenging capacity (HPSC) (r = −0.294, P < 0.0001), (b) total number of follicles (r = −0.246, P < 0.001) and (c) total number of oocytes punctured (r = −0.268, P = 0.0001). The concentration of serum estradiol exhibited a positive correlation with intrafollicular HPSC (r = 0.165, P = 0.037). Our data indicate that the FF levels of estradiol and progesterone are related to the FF redox status, which is closely associated with the number of oocytes obtained during ICSI procedures.

Impact of exogenous gonadotropin stimulation on circulatory and follicular fluid cytokine profiles

Background. The natural cycle is the prototype to which we aspire to emulate in assisted reproduction techniques. Increasing evidence is emerging that controlled ovarian hyperstimulation (COH) with exogenous gonadotropins may be detrimental to oogenesis, embryo quality, and endometrial receptivity. This research aimed at assessing the impact of COH on the intrafollicular milieu by comparing follicular fluid (FF) cytokine profiles during stimulated in vitro fertilization (IVF) and modified natural cycle (MNC) IVF. Methods. Ten women undergoing COH IVF and 10 matched women undergoing MNC IVF were recruited for this pilot study. 40 FF cytokine concentrations from individual follicles and plasma were measured by fluid-phase multiplex immunoassay. Demographic/cycle/cytokine data were compared and correlations between cytokines were computed. Results. No significant differences were found between COH and MNC groups for patient and cycle demographics, including outcome. Overall mean FF cytokine levels were higher in the MNC group for 29/40 cytokines, significantly so for leukaemia inhibitory factor and stromal cell-derived factor-1α. Furthermore, FF MNC cytokine correlations were significantly stronger than for COH data. Conclusions. These findings suggest that COH perturbs intrafollicular cytokine networks, in terms of both cytokine levels and their interrelationships. This may impact oocyte maturation/fertilization and embryo developmental competence.

Elevated levels of oxidized low-density lipoprotein and of catalase activity in follicular fluid of obese women

The intrafollicular levels of oxidized low-density lipoprotein (oxLDL) and of enzyme antioxidants might contribute to reproductive disorders in obese and infertile women. Relevant data are missing. Eighty-four patients were grouped according to obese versus non-obese status and whether they had polycystic ovary syndrome (PCOS). The concentrations of oxLDL and the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and glutathione reductase (GR) in the serum and follicular fluid were measured. Obese women with and without PCOS had significantly greater amounts of oxLDL in the follicular fluid as compared with non-obese women. The level of oxLDL in the follicular fluid was 1000 times lower than in serum. Obese women with and without PCOS had significantly higher catalase activity in the follicular fluid as compared with non-obese women. No differences were found for the SOD activity in the follicular fluid. The GPx and GR activities were up-regulated in obese patients without and with PCOS, yet not in respect to each serum and follicular fluid sample. We conclude that elevated levels of oxLDL in the follicular fluid of obese women are associated with higher catalase activity; both parameters are independent of PCOS. The levels of oxLDL and catalase activity appear to indicate different degrees of oxidative stress.

Superoxide dismutase activity in human follicular fluid after controlled ovarian hyperstimulation in women undergoing in vitro fertilization

OBJECTIVE

To determine the activity of superoxide dismutase (SOD) and the total protein concentration in human preovulatory ovarian follicular fluid (FF) in relation to corresponding serum levels and the fertilization capacity of oocytes.

DESIGN

Prospective, observational study.

SETTING

Academic-based center for reproductive medicine.

PATIENT(S)

Twenty-eight female partners of infertile couples, 13 of whom were smokers, undergoing controlled ovarian hyperstimulation for IVF.

INTERVENTION(S)

Blood and follicular fluid samples were collected 34-36 hours after hCG administration.

MAIN OUTCOME MEASURE(S)

Levels of SOD activity and total protein concentrations.

RESULT(S)

Superoxide dismutase activity was present in all the FF studied and mean levels were statistically significantly higher than in serum. Total protein concentrations in serum were statistically significantly correlated with corresponding concentrations in FF. There was no difference in SOD activity between smokers and nonsmokers. Total protein concentrations in FF were marginally and statistically significantly lower in nonsmokers. Follicular fluid from patients whose oocytes did not become fertilized had a statistically significantly higher level of SOD activity than that from patients whose oocytes did become fertilized.

CONCLUSION(S)

Superoxide dismutase activity is present in FF and is higher than in serum. The degree of SOD activity is variable and seems to be inversely related to the fertilization of oocytes.

The detection of blood contamination in human follicular fluid

PURPOSE

The aim of this study was to compare the reliability of the methods conventionally used to identify low levels of blood contamination in human follicular fluid (hFF) as applicable in the clinical environment.

METHODS

Follicular fluid (n = 339) and plasma samples (n = 20) were collected from patients (n = 138) attending the Centre for Fertility Studies, HF Verwoerd Hospital, University of Pretoria, South Africa. hFF blood contamination was assessed by means of (a) visual inspection, (b) hematocrit (Hct), (c) spectrophotometric analysis, (d) spectrophotometric hemoglobin kit, and (e) Combur-9-test urine sticks.

RESULTS

(1) Neither hematocrit nor spectrophotometry provided reliable detection at low levels of blood contamination. (2) Visual inspection presented with a better discriminatory ability than either Hct or spectrophotometry. (3) Combur-9-test sticks identified up to 50% of blood-contaminated fluids. (4) Spectrophotometrically determined hemoglobin levels presented with weak discriminatory abilities for detecting blood-contaminated fluids.

CONCLUSIONS

Visual inspection as performed in this study provides a fast and relatively reliable method for the determination of blood-contaminated hFFs. In a laboratory environment, however, it would be recommended that a combination of visual inspection, Hct, and spectrophotometric evaluation be employed for the selection of blood-free fluids.

Interleukin-1 beta, interleukin-6, and growth hormone levels in human follicular fluid

PURPOSE

To investigate possible relationships of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and growth hormone (GH) with biochemical variables in human follicular fluid (FF) and selected in vitro fertilization (IVF) parameters.

METHODS

A total of 67 FF samples (n = 67 patients undergoing oocyte retrieval for IVF) was evaluated. IL-1 beta, IL-6, GH, hLH, FSH, PRL, hCG, testosterone, total protein, fibrinogen, sialic acid, alpha 1-antitrypsin, plasminogen levels, and spectrophotometric absorbance at 458 nm were analyzed for selected FF. IL-6 and GH levels of serum and FF samples were also compared (n = 23).

RESULTS

Immunoreactive levels of IL-1 beta, IL-6, and GH were detected in all FF samples. A positive correlation existed for IL-6 (r = 0.5069, P = 0.0161) when serum-to-FF levels were compared (concentration ratio, 1:1.857). Smaller-volume follicles (< 4 ml) were associated with high IL-1 beta levels (P = 0.0229), and an additional tendency of IL-1 beta to decrease with increasing embryo cleavage and scoring was observed. With the exception of a weak positive correlation between follicular IL-1 beta and testosterone levels (r = 0.3128, P = 0.025), no other relationship with biochemical variables or IVF parameters (etiology, e.g., endometriosis) could be implicated.

CONCLUSIONS

Substantially higher IL-6 levels occurred in FF compared to serum, thus supporting intrafollicular production. Interleukin-1 beta, IL-6, and GH levels in FF are, however, unsuitable markers for in vitro fertilization outcome.

Spectrophotometric analysis of human follicular fluid with regard to in vitro fertilization (IVF) parameters, follicular protein, and hormone content

PURPOSE

Our purpose was to investigate possible relationships with spectrophotometric absorbance (458-nm region) and biochemical variables in follicular fluid (FF) as well as in vitro fertilization (IVF) outcome.

METHODS

This study included 227 normal ovulatory women undergoing oocyte retrieval for IVF. Blood-uncontaminated fluid samples, identified by spectrophotometry, were investigated. Spectrophotometric absorbance of FF at 458 nm (n = 426), as well as hLH, FSH, PRL, hCG, testosterone, sialic acid, alpha 1-antitrypsin and plasminogen of selected fluids, was analyzed.

RESULTS

Small-volume follicles (< or = 2 ml) were associated with higher absorbance profiles (P < 0.05), when compared to volumes greater than 2 ml. Our data suggest that the presence or absence of an oocyte, the potential of an oocyte to fertilize or cleave, failed to show any relationship with maximum FF absorbance at 458 nm. Maximum absorbances were significantly lower in FF from patients who subsequently became clinically pregnant (P = 0.039). No correlation between FF absorbances and biochemical parameters (P > 0.15) were established.

CONCLUSIONS

Absorbance of clear FF at 458 nm should not be viewed as the single parameter to predict oocyte development in vitro.