Definition and measurement of follicle stimulating hormone

Inflammation and Ovarian Function in Reproductive-Aged Women

INTRODUCTION

Inflammation is a marker of immune activation. Inflammation may have an effect on both ovarian function and luteal function, both essential to pregnancy. High inflammation may also signal dysregulated processes within the ovary, which could be in part measured through Anti-Müllerian hormone, follicle-stimulating hormone, and inhibin B levels.

OBJECTIVE

To determine the relationship between inflammation, measured by C-reactive protein, and three biomarkers of ovarian function during the early follicular phase: Anti-Müllerian hormone, follicle-stimulating hormone, and inhibin B.

METHODS

Secondary cross-sectional analysis of data and serum obtained in Time to Conceive, a prospective cohort study sample of 843 women attempting pregnancy in central North Carolina from 2008 to 2016. Participants were aged 30 and 44 years, had no history of infertility, endometriosis, or polycystic ovarian syndrome, and were not currently breastfeeding. Serum samples were obtained on days 2, 3, or 4 of the menstrual cycle. C-reactive protein (natural-log transformed), Anti-Müllerian hormone (natural-log transformed), follicle-stimulating hormone (natural-log transformed), and inhibin B (untransformed) were measured in serum. Diminished ovarian reserve was examined dichotomously and defined as an Anti-Müllerian hormone level below 0.7 ng/mL.

RESULTS

The analysis included 703 participants with C-reactive protein measured. In an adjusted linear regression model, a 20% increase in C-reactive protein was associated with a 0.57 pg/mL decrease in inhibin B (95% CI: -0.84 to -0.29 pg/mL) and a 0.535% decrease in follicle-stimulating hormone (95% CI: -1.01 to -0.06). Although there was not a significant relationship between Anti-Müllerian hormone and C-reactive protein, a 20% increase in C-reactive protein was associated with a 0.87% increase in Anti-Müllerian hormone (95% CI: -0.27 to 2.01). C-reactive protein was not associated with the odds of diminished ovarian reserve in an adjusted logistic regression model (OR: 0.97, 95% CI: 0.77-1.20).

CONCLUSIONS

Inflammation, as measured by C-reactive protein, is associated with early follicular phase follicle-stimulating hormone and inhibin B, although this is not true of AMH. Inflammation may exert an effect on ovarian function.

Follicle-Stimulating Hormone and Diabetes in Postmenopausal Women: A Systematic Review and Meta-Analysis

CONTEXT

The co-occurrence of hormonal changes during menopause and the risk of cardio-metabolic disorders has been well studied.

OBJECTIVE

We explored the association of circulating levels of follicle-stimulating hormone (FSH) with diabetes (DM) among postmenopausal women.

METHOD

In this systematic review and meta-analysis, the search was performed in PubMed, Scopus, Web of Sciences, Epistemonikos, and Cochrane Library up to September 2023. Risk of bias was assessed by Newcastle-Ottawa Quality Assessment Scale. Pooled estimates of mean differences in FSH levels were compared between postmenopausal women with and without DM. Correlations between FSH and fasting blood glucose (FBG)/insulin/homeostatic model assessment for insulin resistance (HOMA-IR) as well as pooled effect sizes with their 95% CIs for risk of DM were calculated.

RESULTS

In this study, 14 articles, including 7878 postmenopausal women, met eligibility criteria. Most of the included studies had a low/moderate risk of bias. Women with DM had significantly lower FSH levels than those without DM (standardized mean difference [SMD] -0.751 [95% CI, -1.129 to -.372], I2 = 82.46%, n = 1416). The pooled effect size for diabetes was 0.861 (95% CI, 0.740-1.001; I2 = 80.11%). The pooled risk estimate for DM based on the categorical FSH levels (high vs low) was (HR = 0.550; 95% CI, 0.356-0.850, I2 = 0). The significant inverse correlation was found between FSH levels and glycemic parameters: FBG (r= -0.285 [95% CI -0.441 to -0.113]; n = 1229), HOMA-IR (r = -0.241[-0.378 to -0.0924]; n = 1229) and insulin (r = -0.337 [-0.434 to -0.232]; n = 959)]. There were no statistically significant differences between estradiol levels among diabetic and nondiabetic groups; however, the SMD for luteinizing hormone was similar to that reported for FSH.

CONCLUSION

The available data indicated an indirect association between FSH levels and glucose disturbances among postmenopausal women, notwithstanding heterogeneity among included studies, and the complexity of various influential factors needs to be considered. Further efforts should be made to clarify the underlying mechanisms.

Association of 'normal' early follicular FSH concentrations with unexpected poor or suboptimal response when ovarian reserve markers are reassuring: a retrospective cohort study

RESEARCH QUESTION

Are basal FSH measurements, when elevated within its normal range, useful for assessing overall ovarian response and predicting unexpected poor or suboptimal ovarian response?

DESIGN

Retrospective cohort study of ovarian stimulation cycles.

RESULTS

A total of 1058 ovarian stimulation cycles (891 first, 167 repeated) were included. Anti-Müllerian hormone (AMH) values were categorized into four (0 to ≤0.6, >0.6 to ≤1.2, >1.2 to ≤3.0, >3.0 to ≤6.25 ng/ml) and basal FSH levels into four groups (<25th percentile: >3.5 to 6.1 IU/ml; 25-75th percentile: >6.1 to ≤8.5 IU/ml; >75-90th percentile: >8.5 to ≤9.9 IU/ml; >90th percentile: >9.9 to ≤12.5 IU/ml). Including only first cycles, a significant independent effect of basal FSH on retrieved cumulus-oocyte complex (COC) count was seen for all basal FSH categories (>90th, >75 to ≤90th, >25 to ≤75th compared with ≤25th percentile, P < 0.001, P = 0.001 and P = 0.007, respectively), when adjusted for age, body mass index (BMI), AMH, antral follicle count (AFC), starting dose and gonadotrophin type. Including only first cycles, patients aged 35 years or older with AFC of 5 or above and AMH 1.2 ng/ml or above, showed significantly higher odds of unexpected poor or suboptimal response if they had higher basal FSH values. Most prominently in the above 90th percentile group (OR 8.64, 95% CI 2.84 to 28.47 compared with <25th percentile) but lower categories (>25th to ≤75th percentile: OR 3.04, 95% CI 1.42 t 6.99; >75th to ≤90th percentile: OR 3.47, 95% CI 1.28 to 9.83 compared with ≤25th percentile) also showed a significant association after adjusting for age, AMH, BMI, AFC, dose, and gonadotrophin type. In patients with a second cycle, an increase in FSH levels in the second round compared with the first was associated with fewer retrieved COCs (estimate: -0.44, 95% CI -0.44 to -0.05, P = 0.027). This effect was adjusted for changes in age, FSH, AFC, starting dose, stimulation duration and change in medication type.

CONCLUSIONS

Basal FSH is independently associated with overall ovarian response. Moreover, it is associated with unexpected poor or suboptimal response in patients, who would fulfill POSEIDON group 2 criteria after oocyte retrieval.

Impacts of PAH accumulation on reproductive hormones, indices of oxidative stress and BPDE-albumin adduct in women with recurrent pregnancy loss

Chronic exposure to Poly aromatic hydrocarbons (PAHs) may be associated with adverse pregnancy outcomes. Disruption of hormonal and redox balance by toxic PAH metabolites may interfere with successful pregnancy leading to miscarriage. The association of exposure to PAH contaminated mussel via the dietary route with perturbations in reproductive hormones, biomarkers of oxidative stress, and PAH metabolites were assessed in women with recurrent pregnancy loss (RPL). Furthermore, an analysis of the concentration of PAHs in environmentally relevant bivalve animals was performed to preliminary get insights into the levels of these pollutants in the environment. Seventy-six women (20-35 years) were categorized into 18 fertile women without RPL (control), and Groups I, II, and III comprising 24, 18, and 16 women with RPL (2, 3, and > 3 abortions respectively) were studied. Whole blood samples were collected for the estimation of malondialdehyde (MDA), catalase, reduced glutathione (GSH), glutathione-S-transferase (GST), progesterone (P4), follicle-stimulating hormone (FSH), benzo[a]pyren-7,8-dihydrodiol-9,10-epoxide-albumin adduct (BPDE-albumin) and urine for α-naphthol and β-naphthol. Two species of mussel Donax trunculus and Andar aduloii samples were collected for the estimation of 16 priority PAHs. The concentration of PAHs exceeding the maximum limits was observed in the two species of mussels studied. Higher levels of BPDE-albumin, MDA, GST, α and β-naphthol and lower GSH, catalase, FSH, and P4 were observed in women with RPL (Groups I-III) compared to controls (p =  < 0.001). Negative associations were observed between BPDE-albumin and catalase (r = - 0.276, p = 0.036), and GSH (r = - 0.331, p = - 0.011) only in women with RPL. Collectively, our findings indicate a possible association of chronic PAH accumulation with recurrent pregnancy loss in women.

Graphical abstract

High PAH exposure in pregnant women is associated with 10-epoxide-albumin adduct formation and high MDA levels in their sera. On the other hand, PAH exposure in those women led to a decrease in their GSH, catalase, P4, and FSH sera levels. These findings indicate that PAH exposure can exert different physiological effects in pregnant women leading to a high level of abortion in those women.

Biological Assay to Determine Gonadotropin Potency: From In Vivo to In Vitro Sustainable Method

Various preparations of follicle-stimulating hormone (FSH) are commercially available; however, they differ in glycoforms composition and purity owing to their respective sources. Additional chemical/physical changes can also be introduced during manufacturing and can impact their biological activity (biopotency), which is routinely assessed using an in vivo bioassay (Steelman-Pohley). This study aimed to determine whether an in vitro bioassay could assess biopotency by distinguishing between r-hFSH chemical/physical variants with similar ability to the in vivo bioassay. The specific activity (units of biological activity per mg of product) of variants of r-hFSH generated through enrichment (acidic/basic), stress (oxidative/acidic pH) and enzymatic treatment (desialylation and desialylation/degalactosylation) was compared using the in vivo and in vitro bioassays. The in vitro bioassay reliably detected potential chemical/physical modifications in r-hFSH variants that may impact biopotency. Overall, the methods demonstrated a comparable ability to detect changes in specific activities due to chemical/physical differences in r-hFSH variants. These data indicate that the in vitro bioassay is suitable to replace the in vivo bioassay.

First pre-filled pen device with highly purified human menopausal gonadotropin (HP-hMG, Menopur) in liquid is shown to be bioequivalent to powder for reconstitution

OBJECTIVE

To determine whether serum human follicle-stimulating hormone (FSH) levels after single subcutaneous dosing of highly purified human menopausal gonadotropins (HP-hMG) in a liquid formulation and a powder formulation are bioequivalent.

MATERIALS AND METHODS

This was a randomized, two-way, crossover, single-dose, bioequivalence trial comparing Menopur liquid injected by pre-filled pen, with Menopur powder injected by conventional syringe and needle. The primary endpoints were AUC_t and C_max of baseline-adjusted FSH. Pituitary-suppressed, healthy women were administered single subcutaneous injections of 450 IU Menopur liquid (600 IU/0.96 mL) and 450 IU Menopur powder (by 2 subcutaneous injections of 225 IU in 1 mL) in a randomized order. The pharmacokinetic parameters of FSH and human chorionic gonadotropin (hCG) were assessed by non-compartmental methods with adjustment for endogenous pre-dose levels.

RESULTS

In total, 76 women were randomized, and 56 completed the trial. The mean FSH and hCG serum concentration-time profiles were comparable between the two HP-hMG formulations. The geometric mean ratios and 90% confidence intervals of FSH for HP-hMG liquid versus HP-hMG powder were 1.12 (1.0562 - 1.1889) for AUC_t and 1.17 (1.0946 - 1.2490) for C_max, showing that the two formulations were bioequivalent. The incidence and severity of adverse events were similar between the two preparations, and both preparations were well tolerated.

CONCLUSION

The 90% CIs for the geometric mean ratios of serum FSH AUC_t and C_max were both within 0.8000 - 1.2500, thus the two formulations are bioequivalent.

Identification and Relative Quantification of hFSH Glycoforms in Women's Sera via MS-PRM-Based Approach

Follicle-stimulating hormone (FSH) is a glycohormone synthesized by adenohypophysis, and it stimulates ovulation in women and spermatogenesis in men by binding to its receptor (FSHR). FSHR is involved in several mechanisms to transduce intracellular signals in response to the FSH stimulus. Exogenous FSH is currently used in the clinic for ovarian hyperstimulation during in vitro fertilization in women, and for treatment of infertility caused by gonadotropin deficiency in men. The glycosylation of FSH strongly affects the binding affinity to its receptor, hence significantly influencing the biological activity of the hormone. Therefore, the accurate measurement and characterization of serum hFSH glycoforms will contribute to elucidating the complex mechanism of action by which different glycoforms elicit distinct biological activity. Nowadays ELISA is the official method with which to monitor serum hFSH, but the test is unable to distinguish between the different FSH glycovariants and is therefore unsuitable to study the biological activity of this hormone. This study presents a preliminary alternative strategy for identifying and quantifying serum hFSH glycoforms based on immunopurification assay and mass spectrometry (MS), and parallel reaction monitoring (PRM) analysis. In this study, we provide an MS–PRM data acquisition method for hFSH glycopeptides identification with high specificity and their quantification by extracting the chromatographic traces of selected fragments of glycopeptides. Once set up for all its features, the proposed method could be transferred to the clinic to improve fertility treatments and follow-ups in men and women.

Anti-hyperprolactinemic activities of aqueous extract of Uvaria chamae (P. Beauv) roots and associated biochemical changes in chlorpromazine-induced hyperprolactinemic female Wistar rats

ETHNOPHARAMCOLOGICAL RELEVANCE

The age-long folkloric use of Uvaria chamae roots in the management of nipple discharge that is not related to pregnancy, childbirth or nursing but as a result of excessive production of prolactin (hyperprolactinemia) is yet to be substantiated with scientific data.

AIM OF THE STUDY

This study investigated the anti-hyperprolactinemic activities of aqueous extract of Uvaria chamae roots (AEUCR) and associated biochemical changes in chlorpromazine (CPZ)-induced hyperprolactinemic female Wistar rats.

MATERIALS AND METHODS

A total of sixty female rats (207.40 ± 2.69 g) were assigned into 6 groups: A-F. Animals in Group A received 0.5 ml of distilled water only whilst the 7 days CPZ-treated female rats (to induce hyperprolactinemia) in groups B, C, D, E, and F also received distilled water, 2.5 mg/kg body weight of bromocriptine (reference drug), 0.71, 1.41 2.83 mg/kg body weight of AEUCR for 28 days.

RESULTS

AEUCR contained a total of 15 (75%) amino acids with seven (46.67%) being essential amino acids and eight (53.33%) as non-essential amino acids. Administration of CPZ increased (p < 0.05) the levels of prolactin and testosterone, and reduced (p < 0.05) the levels of estradiol, progesterone, follicle stimulating hormone (FSH), luteinizing hormone (LH), dopamine, triiodothyronine (T3) and tetraiodothyroxine (T4). Chlorpromazine also increased the levels of serum urea, creatinine, total protein, albumin, globulin, bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) of the animals. In contrast, AEUCR significantly (p < 0.05) reduced the CPZ-induced increases in the levels of prolactin and testosterone, and increased the levels of CPZ-induced reduction in the progesterone, estradiol, FSH, LH, dopamine, T3 and T4. The AEUCR also reversed (p < 0.05) the CPZ-induced related increases in the levels of urea, creatinine, total protein, albumin, globulin, bilirubin, ALT, AST and ALP similar to the trends in the distilled water- and bromocriptine-treated controls. The CPZ-induced remarkable increase in the size of lactating alveolus and lactiferous duct distribution in the mammary gland were restored to normal tubule-alveolar female pattern mammary glands, composed of branching ducts and small alveoli budding off the ducts.

CONCLUSION

The study concluded that aqueous extract of Uvaria chamae root exhibited anti-hyperprolactinemic activity by restoring prolactin and dopamine levels and tubule-alveolar female pattern in female rats. It also ameliorated CPZ-induced changes in the liver and kidney function indices. This study justifies the folkloric use of Uvaria chamae root in the management of abnormal discharge by the nipples that is unrelated to pregnancy, childbirth and nursing.

Saccharum officinarum juice alters reproductive functions in male Wistar rats

Infertility is a problem across almost all cultures and societies. Problems in the male partner, especially as a result of unhealthy dietary habits, are the commonest single group of course. Many populations, therefore, tend more toward the use of natural dietary substitutes opined to proffer less risk to reproductive functions and more health benefits. Saccharum officinarum juice (SOJ) is a widely consumed, energy-rich, nutritious substance that has many minerals and enzymes. Saccharum officinarum plant was reported to have anti-thrombosis, anti-inflammatory and immune-stimulatory activities. This study evaluated the reproductive effects of S. officinarum juice in male Wistar rats. A sugarcane press juicer was used to extract S. officinarum juice. Twenty male Wistar rats (100-120 g) grouped into four (n = 5) received 1.0 mL/kg/day distilled water (control), and 1.0, 3.2 and 10.0 mL/kg/day of fresh S. officinarum juice once daily for 8 weeks via gavage. Sperm analysis, histology of testes and epididymides were evaluated by microscopy. Enzyme-linked immunosorbent assay (ELISA) was used in assessing the serum levels of luteinizing hormone, follicle-stimulating hormone and testosterone. Data were analyzed using the analysis of variance at a significance of p < 0.05. SOJ increased fasting blood glucose levels in 3.2 and 10.0 mL/kg groups. The 10.0 mL/kg juice caused a significant increase in testosterone level and sperm count, and it also increased the percentage of aberrant sperm and decreased sperm viability. Saccharum officinarum juice impaired the histological integrity of the testes and epididymides. Thus, S. officinarum juice adversely altered the reproductive functions of male Wistar rats by reducing sperm quality and disrupting testicular architecture.

The gonadotropin system, lessons from animal models and clinical cases

This review article centers upon family of gonadotropin hormones which consists of two pituitary hormones - follicle-stimulating hormone (FSH) and luteinizing hormone (LH) as well as one non-pituitary hormone - human chorionic gonadotropin (hCG) secreted by placenta, and their receptors. Gonadotropins play an essential role in proper sexual development, puberty, gametogenesis, maintenance of pregnancy and male sexual differentiation during the fetal development. They belong to the family of glycoprotein hormones thus they constitute heterodimeric proteins built of common α subunit and hormone-specific β-subunit. Hitherto, several mutations in genes encoding both gonadotropins and their receptors have been identified in humans. Their occurrence resulted in a number of different phenotypes including delayed puberty, primary amenorrhea, hermaphroditism, infertility and hypogonadism. In order to understand the effects of mutations on the phenotype observed in affected patients, detailed molecular studies are required to map the relationship between the structure and function of gonadotropins and their receptors. Nonetheless, in vitro assays are often insufficient to understand physiology. Therefore, several animal models have been developed to unravel the physiological roles of gonadotropins and their receptors.

Effects of Cadmium Exposure on DNA Methylation at Imprinting Control Regions and Genome-Wide in Mothers and Newborn Children

BACKGROUND

Imprinted genes are defined by their preferential expression from one of the two parental alleles. This unique mode of gene expression is dependent on allele-specific DNA methylation profiles established at regulatory sequences called imprinting control regions (ICRs). These loci have been used as biosensors to study how environmental exposures affect methylation and transcription. However, a critical unanswered question is whether they are more, less, or equally sensitive to environmental stressors as the rest of the genome.

OBJECTIVES

Using cadmium exposure in humans as a model, we aimed to determine the relative sensitivity of ICRs to perturbation of methylation compared to similar, nonimprinted loci in the genome.

METHODS

We assayed DNA methylation genome-wide using bisulfite sequencing of 19 newborn cord blood and 20 maternal blood samples selected on the basis of maternal blood cadmium levels. Differentially methylated regions (DMRs) associated with cadmium exposure were identified.

RESULTS

In newborn cord blood and maternal blood, 641 and 1,945 cadmium-associated DMRs were identified, respectively. DMRs were more common at the 15 maternally methylated ICRs than at similar nonimprinted loci in newborn cord blood (p=5.64×10^-8) and maternal blood (p=6.22×10^-14), suggesting a higher sensitivity for ICRs to cadmium. Genome-wide, Enrichr analysis indicated that the top three functional categories for genes that overlapped DMRs in maternal blood were body mass index (BMI) (p=2.0×10^-5), blood pressure (p=3.8×10^-5), and body weight (p=0.0014). In newborn cord blood, the top three functional categories were BMI, atrial fibrillation, and hypertension, although associations were not significant after correction for multiple testing (p=0.098). These findings suggest that epigenetic changes may contribute to the etiology of cadmium-associated diseases.

CONCLUSIONS

We analyzed cord blood and maternal blood DNA methylation profiles genome-wide at nucleotide resolution in individuals selected for high and low blood cadmium levels in the first trimester. Our findings suggest that ICRs may be hot spots for perturbation by cadmium, motivating further study of these loci to investigate potential mechanisms of cadmium action. https://doi.org/10.1289/EHP2085.

Affinity-based biosensors in sport medicine and doping control analysis

Affinity-based biosensors (ABBs) have started to be considered in sport medicine and doping control analysis because they are cheap, easy to use and sufficiently selective analytical devices, characterized by a reversible interaction with the analyte under investigation allowing the use of the same sensor for multiple analyses. In this review we describe the main categories of substances reported in the World Anti-Doping Agency Prohibited List and how ABBs may contribute to their detection. Although several ABBs proposed in the last few years display limit of detections that are in principle matching the World Anti-Doping Agency requirements, their application in the framework of 'traditional' antidoping tests seems quite unlikely, mainly because of the still insufficient selectivity especially in the case of 'pseudo-endogenous' compounds, and on the lack of complete information regarding potential matrix effects in real samples and following their routine use. At the same time, ABBs could contribute to fill a significant information gap concerning complementary evidence that can be obtained from their use 'on the spot', as well as to preselect a risk population of individuals to be targeted for a full antidoping test; while in sport medicine they could contribute to obtaining analytical information of physiological relevance from the measurement of specific parameters or markers before, during and after physical exercise.

Use of a single injection of long-acting recombinant bovine FSH to superovulate Holstein heifers: a preliminary study

Our objective was to compare several experimental preparations of a single injection of long-acting recombinant bovine FSH (rbFSH; types A and B) to a porcine pituitary-derived FSH (Folltropin) to superovulate Holstein dairy heifers. Nonlactating, nonpregnant virgin Holstein heifers (n = 56) aged 12 to 15 months were randomly assigned to one of four superstimulatory treatments. Beginning at a random stage of the estrous cycle, all follicles greater than 5 mm were aspirated. Thirty-six hours later, heifers received an intravaginal P4 device and superstimulatory treatments were initiated. Treatments were (1) 300 mg of pituitary-derived FSH (Folltropin) administered in eight decreasing doses over a period of 3.5 days; (2) a single injection of 50 μg of A-rbFSH; (3) a single injection of 100 μg of A-rbFSH; and (4) a single injection of 50 μg of B-rbFSH. All heifers received 25 mg PGF2α at 48 and 72 hours after the insertion of P4 device. At 84 hours after insertion, P4 devices were removed, and ovulation was induced 24 hours later with hCG (2500 IU). Heifers were inseminated at 12 and 24 hours after hCG treatment. The number of ovulatory follicles was greatest for heifers treated with Folltropin and B50-rbFSH, least for heifers treated with A50-rbFSH, and was intermediate for heifers treated with A100-rbFSH (25.7 ± 3.2, 18.9 ± 3.2, 5.9 ± 0.9, and 16.6 ± 3.1, respectively; P < 0.001). The number of corpora lutea was greatest for heifers treated with Folltropin, B50-rbFSH, and A100-rbFSH, and least for heifers treated with A50-rbFSH (19.1 ± 2.4, 16.1 ± 3.0, 15.9 ± 2.9, and 2.6 ± 0.9, respectively; P < 0.001). The number of good-quality embryos differed among treatments and was greatest for heifers treated with B50-rbFSH, Folltropin, and A100-rbFSH and least for heifers treated with A50-rbFSH (7.6 ± 2.4, 6.5 ± 1.7, 4.3 ± 1.5, and 0.8 ± 0.5, respectively; P < 0.001). In conclusion, a single injection of a preparation of long-acting rbFSH (either 100 μg of A-rbFSH or 50 μg of B-rbFSH but not 50 μg of A-rbFSH) produced similar superovulatory responses resulting in the production of good-quality embryos when compared with a pituitary-derived FSH preparation administered twice daily for 4 days. More studies using different types of cattle and different doses of rbFSH are needed to confirm the findings reported in this preliminary study.

Endocrine disrupting effects of dichlorodiphenyltrichloroethane analogues on gonadotropin hormones in pituitary gonadotrope cells

It has been shown that exposure to dichlorodiphenyltrichloroethane (DDT) analogues leads to disharmony of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). However, the effects and mechanisms of DDT analogues on the expression of gonadotropin genes (FSHβ, LHβ and Cgα), which is the rate-limiting step of FSH and LH biosynthesis, remain unknown. In this study, we assessed the effects of p,p'-DDT, o,p'-DDT, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and methoxychlor (MXC) on gonadotropin genes expression and hormones synthesis in gonadotrope cells. p,p'-DDT and MXC at test concentrations ranging from 10(-9) to 10(-7)mol/L, stimulated gonadotropin genes expression and hormones synthesis in a dose-dependent manner. The activation of extracellular signal-regulated kinase (ERK) was required for the induction of gonadotropin genes expression and hormones synthesis by p,p'-DDT or MXC exposure. This study showed for the first time that p,p'-DDT and MXC regulated gonadotropin genes expression and hormones synthesis through ERK pathway in gonadotrope cells.

Effect of different superovulation stimulation protocols on adenosine triphosphate concentration in rabbit oocytes

Ovarian stimulation protocols are used usually to increase the number of oocytes collected. The determination of how oocyte quality may be affected by these superovulation procedures, therefore, would be very useful. There is a high correlation between oocyte ATP concentration and developmental competence of the resulting embryo. The aim of this study was to evaluate the effect of follicle stimulating hormone (FSH) origin and administration protocols on oocyte ATP content. Rabbit does were distributed randomly into four groups: (i) a control group; (ii) the rhFSH3 group: females were injected, every 24 h over 3 days, with 0.6 μl of rhFSH diluted in polyvinylpyrrolidone (PVP); (iii) the pFSH3 group: females were injected every 24 h over 3 days with 11.4 μg of pFSH diluted in PVP; and (iv) the pFSH5 group: females were injected twice a day for 5 days with 11.4 μg of pFSH diluted in saline serum. Secondly, the effect of pFSH5 protocol on developmental potential was evaluated. Developmental competence of oocytes from the control and pFSH5 groups was examined. Differences in superovulation treatments were found for ATP levels. In the pFSH5 group, the ATP level was significantly lower than that of the other groups (5.63 ± 0.14 for pFSH group versus 6.42 ± 0.13 and 6.19 ± 0.15 for rhFSH3 and pFSH3, respectively; P < 0.05). In a second phase, only 24.28% of pFSH5 ova developed into hatched blastocysts compared with 80.39% for the control group. A negative effect on oocyte quality was observed in the pFSH5 group in ATP production, it is possible that, after this superovulation treatment, oocyte metabolism would be affected.

LH and hCG action on the same receptor results in quantitatively and qualitatively different intracellular signalling

Human luteinizing hormone (hLH) and chorionic gonadotropin (hCG) act on the same receptor (LHCGR) but it is not known whether they elicit the same cellular and molecular response. This study compares for the first time the activation of cell-signalling pathways and gene expression in response to hLH and hCG. Using recombinant hLH and recombinant hCG we evaluated the kinetics of cAMP production in COS-7 and hGL5 cells permanently expressing LHCGR (COS-7/LHCGR, hGL5/LHCGR), as well as cAMP, ERK1/2, AKT activation and progesterone production in primary human granulosa cells (hGLC). The expression of selected target genes was measured in the presence or absence of ERK- or AKT-pathways inhibitors. In COS-7/LHCGR cells, hCG is 5-fold more potent than hLH (cAMP ED₅₀: 107.1±14.3 pM and 530.0±51.2 pM, respectively). hLH maximal effect was significantly faster (10 minutes by hLH; 1 hour by hCG). In hGLC continuous exposure to equipotent doses of gonadotropins up to 36 hours revealed that intracellular cAMP production is oscillating and significantly higher by hCG versus hLH. Conversely, phospho-ERK1/2 and -AKT activation was more potent and sustained by hLH versus hCG. ERK1/2 and AKT inhibition removed the inhibitory effect on NRG1 (neuregulin) expression by hLH but not by hCG; ERK1/2 inhibition significantly increased hLH- but not hCG-stimulated CYP19A1 (aromatase) expression. We conclude that: i) hCG is more potent on cAMP production, while hLH is more potent on ERK and AKT activation; ii) hGLC respond to equipotent, constant hLH or hCG stimulation with a fluctuating cAMP production and progressive progesterone secretion; and iii) the expression of hLH and hCG target genes partly involves the activation of different pathways depending on the ligand. Therefore, the LHCGR is able to differentiate the activity of hLH and hCG.

Single- and multi-analyte determination of gonadotropic hormones in urine by Surface Plasmon Resonance immunoassay

Single- and multi-analyte detection of two gonadotropic hormones (follicle stimulating hormone (hFSH) and luteinizing hormone (hLH)) was achieved by a Surface Plasmon Resonance (SPR) immunoassay on untreated human urine samples. Multi-analyte detection was accomplished using two alternative formats which are based in the individual or simultaneous immobilization of the hormones on the sensor surface. The lowest detection limit for both hormones in urine was found to be 1 ng mL(-1), which in international units (IU) in terms of the World Health Organization (WHO) standards represents 8 mIU mL(-1) of hLH and 14 mIU mL(-1) of hFSH, respectively. The reliability of the assay was demonstrated by intra- and inter-assay variabilities < 6%, chip-to-chip variabilities < 5%, recoveries in the range of 80-120% and stability of the sensor response through more than 100 measurements. The sensitivity of this biosensing methodology renders it in a useful technique for the diagnosis of reproductive disorders, as well as for fertility monitoring.

Traceability in laboratory medicine

BACKGROUND

In patient and population samples, generation of analytical results that are comparable and independent of the measurement system, time, and location is essential for the utility of laboratory information supplied in healthcare. Obtaining analytical measurement results with such characteristics is the aim of traceability in laboratory medicine. As awareness of the benefits of having traceable measurement results has increased, associated efforts have been directed toward making traceability a regulatory requirement and developing approaches to enable and facilitate the implementation of traceability. Although traceability has been a main focus of many laboratory standardization activities in the past, discussions are still ongoing with regard to traceability and its implementation.

CONTENT

This review provides information about the traceability concept and what needs can be fulfilled and benefits achieved by the availability of traceable measurement results. Special emphasis is given to the new metrological terminology introduced with this concept. The review addresses and describes approaches for technical implementation of traceable methods as well as the associated challenges. Traceability is also discussed in the context of other activities to improve the overall measurement process.

SUMMARY

Establishing metrological traceability of measurement results satisfies basic clinical and public health needs, thus improving patient care and disease control and prevention. Large advances have been made to facilitate the implementation of traceability. However, details in the implementation process, such as lack of available commutable reference materials and insufficient resources to develop new reference measurement systems continue to challenge the laboratory medicine community.

Functional reconstruction and synthetic mimicry of a conformational epitope using CLIPS technology

This paper describes immunization studies with CLIPS-constrained peptides covering only the major part (beta3-loop) of a structurally complex antigenic site on human Follicle Stimulating Hormone beta-subunit (FSH-beta). In cases where linear and SS-constrained peptides fail, the CLIPS-constrained peptides generate polyclonal antibodies with high neutralizing activity for hFSH. The sera were shown to be specific for hFSH over human Luteinizing Hormone (hLH) and human Chorionic Gonadotropin (hCG). ELISA-competition studies and circular dichroism (CD)-measurements illustrate clearly that activity of the peptides in antibody binding and generation relates directly to precise and appropriate fixation of the peptide conformation. Design of the CLIPS-peptides was entirely based on epitope mapping studies with two neutralizing anti-hFSH mAbs. Both mAbs were shown to bind to a conformational epitope located at the top of the beta1-beta3-loop covering the amino acid sequences Y58-P77 (beta3-loop). The results described in this paper show that CLIPS-constrained peptides covering the Y58-P77 sequence provide the minimally required structural entity necessary to generate reproducibly sera with high hFSH-neutralizing activity.

Comparison of urinary and recombinant follicle-stimulating hormone in in vitro growth, maturation, and fertilization of mouse preantral follicles

OBJECTIVE

To compare the effects of urinary and recombinant follicle-stimulating hormone (FSH) on follicular development, oocyte maturation, and fertilization.

DESIGN

Prospective randomized animal study.

SETTING

University-based research laboratory.

ANIMAL(S)

Normal (C57BL/6xDBA2) F1 mice.

INTERVENTION(S)

Collection of preantral follicles by mechanical dissection, in vitro growth (IVG) with urinary or recombinant FSH (100 mIU/mL), in vitro maturation (IVM), and fertilization.

MAIN OUTCOME MEASURE(S)

During IVG, follicle diameter and antral formation were evaluated. The number of cells per follicle was evaluated at the end of IVG. The 17beta-estradiol measurements were performed from conditioned media. After IVM, mucification and oocyte maturation rates were estimated and mature oocytes were fertilized.

RESULT(S)

No differences were observed in the antral formation rate of either group. Antral follicles in the urinary FSH group, however, showed a higher diameter but a lower number of cells per follicle than those in the recombinant FSH group. The level of 17beta-estradiol was also higher in the recombinant FSH group. The rate of mature oocytes developing into metaphase I or II was statistically significantly higher in the recombinant FSH group than in the urinary FSH group.

CONCLUSION(S)

Recombinant FSH provided better conditions than urinary FSH for the growth and development of mouse preantral follicles that could produce mature oocytes with fertilization capacity.

Analysis of serum levels of anti-Mullerian hormone, inhibin B, insulin-like growth factor-I, insulin-like growth factor binding protein-3, and follicle-stimulating hormone with respect to age and menopausal status

This study was undertaken to investigate age-dependent and postmenopausal changes in the serum levels of anti-Mullerian hormone (AMH), inhibin B, insulin-like growth factor (IGF)-I, IGF-binding protein-3 (IGFBP-3), and follicle-stimulating hormone (FSH), and to determine which of these markers best reflects the aging process in women. A total of 144 women aged 20-59 yr were enrolled in this cross-sectional study. Blood samples were obtained on cycle day 3 of regularly menstruating women (n=111), or at random in postmenopausal women (n=33). Data were analyzed with respect to premenopausal women age groups and compared in pre- and postmenopausal women. Area under the receiver operating characteristic curve (ROCAUC) analyses were performed to assess the ability of each marker to discriminate between the pre- and postmenopausal status. Serum levels of AMH, IGF-I, and IGFBP-3 decreased and serum levels of FSH increased significantly with age in premenopausal women. Serum luteinizing hormone (LH) was higher and inhibin B was lower in women in their 20-30's than in 40's. Serum levels of AMH and IGF-I showed a consistent decrease with all age groups. ROCAUC analysis showed that the diagnostic accuracy of AMH for menopausal status was similar to those of FSH, LH, and inhibin B, and was better than that of IGF-I. In conclusion, the serum AMH level appears to be the best marker of the aging process in premenopausal women.

Delivering non-hormonal contraceptives to men: advances and obstacles

There have been major advances in male contraceptive research during the past two decades. However, for a contraceptive to be used by men, its safety requires more stringent scrutiny than therapeutic compounds for treatment of illnesses because the contraceptives will be used by healthy individuals for an extended period of time, perhaps decades. A wide margin is therefore required between the effective dose range and doses that cause toxicity. It might be preferable that a male contraceptive, in particular a non-hormone-based compound, is delivered specifically and/or directly to the testis and has a rapid metabolic clearance rate, reducing the length of exposure in the liver and kidney. In this article, we highlight the latest developments regarding contraceptive delivery to men and with the aim of providing useful information for investigators in future studies.

Targeted and reversible disruption of the blood-testis barrier by an FSH mutant-occludin peptide conjugate

The blood-testis barrier (BTB) is one of the tightest blood-tissue barriers in mammals. As such, it poses a challenge to deliver any drugs to the seminiferous epithelium of the testis, such as a nonhormonal male contraceptive. To circumvent this problem, a genetically engineered follicle-stimulating hormone (FSH) mutant protein was produced in Spodoptera furgiperda (Sf)-9 insect cells to serve as a testis-specific carrier. Subsequently, a 22-amino acid peptide corresponding to the second extracellular loop of occludin, which was known to disrupt BTB integrity in vivo, was inserted to the FSH mutant by polymerase chain reaction (PCR), as well as chemical cross-linking. This molecule was found to have negligible hormonal activity but was still capable of binding to FSH receptors, which are restricted to Sertoli cells in mammals. When this FSH mutant-occludin peptide conjugate was administered to adult rats at 40 microg/adult rat (approximately 300 gm b.w.) via intraperitoneally (i.p.) injection, it induced transient and reversible disruption of the BTB, while at 150 microg/rat, it induced partial germ cell loss from the testis, particularly elongating/elongate spermatids. Most importantly, this effect was limited to the BTB without compromising the TJ-barrier integrity or cell adhesion in epithelia of other organs, such as kidney, liver, and small intestine. In summary, the use of an FSH mutant-occludin peptide conjugate is a feasible nanodevice to transiently compromise the BTB.

Haplotype structure of FSHB, the beta-subunit gene for fertility-associated follicle-stimulating hormone: possible influence of balancing selection

Follicle-stimulating hormone (FSH) is essential for human reproduction. The unique functions of this hormone are provided by the FSH receptor-binding beta-subunit encoded by the FSHB gene. Resequencing and genotyping of FSHB in three European, two Asian and one African population, as well as in the great apes (chimpanzee, gorilla, orangutan), revealed low diversity and significant excess of polymorphisms with intermediate frequency alleles. Statistical tests for FSHB showed deviations from neutrality in all populations suggesting a possible effect of balancing selection. Two core haplotypes were identified (carried by 76-96.6% of each population's sample), the sequences of which are clearly separated from each other. As fertility most directly affects an organism's fitness, the carriers of these haplotypes have apparently had more success in human history to contribute to the next generation. There is a preliminary observation suggesting that the second most frequent FSHB haplotype may be associated with rapid conception success in females. Interestingly, the same haplotype is related to an ancestral FSHB variant shared with the ancestor of the great apes. The determination of the functional consequence of the two core FSHB variants may have implications for understanding and regulating human fertility, as well as in assisting infertility treatments.

A male contraceptive targeting germ cell adhesion

Throughout spermatogenesis, developing germ cells remain attached to Sertoli cells via testis-specific anchoring junctions. If adhesion between these cell types is compromised, germ cells detach from the seminiferous epithelium and infertility often results. Previously, we reported that Adjudin is capable of inducing germ cell loss from the epithelium. In a small subset of animals, however, oral administration of Adjudin (50 mg per kg body weight (b.w.) for 29 d) resulted in adverse effects such as liver inflammation and muscle atrophy. Here, we report a novel approach in which Adjudin is specifically targeted to the testis by conjugating Adjudin to a recombinant follicle-stimulating hormone (FSH) mutant, which serves as its 'carrier'. Using this approach, infertility was induced in adult rats when 0.5 microg Adjudin per kg b.w. was administered intraperitoneally, which was similar to results when 50 mg per kg b.w. was given orally. This represents a substantial increase in Adjudin's selectivity and efficacy as a male contraceptive.

Validation of an Ultrasensitive and Specific Immunofluorometric Assay for Mouse Follicle-Stimulating Hormone1

Sensitive and specific measurement of FSH is critical to research in reproductive biology, and the increasing availability of transgenic mouse models has created a need for a robust, sensitive, and specific mouse (m) FSH assay. The present study evaluated a time-resolved immunofluorometric assay (IFMA) for mFSH using monoclonal antibody to human (h) FSHbeta as a capture antibody and a biotinylated polyclonal antibody to rat alpha subunit as a detection probe, with signaling amplified by europium-labeled streptavidin. The mFSH IFMA lowered the detection limit 34-fold (5 vs. 170 pg/sample) compared with standard mFSH RIA. The mFSH IFMA demonstrated parallelism of response to dilutions of castrated mouse serum and rat FSH but no cross-reactivity with hFSH and mLH or hLH, whereas the RIA demonstrated nonparallel cross-reactivity with hFSH. The IFMA has a wide analytical range, with a good precision profile for within- and between-assay reproducibility. Because the IFMA is a sandwich-type assay with strict dimer-specificity by design, the lower readings and recovery obtained were compared with the RIA when both assays used a pituitary-purified mFSH assay standard that contained isolated or fragmented subunits as well as intact dimeric FSH. When used with mouse serum sample, the mFSH IFMA demonstrated the expected increases following orchidectomy as well as markedly enhanced sensitivity to very low levels of endogenous mFSH in gonadotropin-deficient mice. Furthermore, the IFMA measured mFSH with fidelity in both intact and orchidectomized male mice without any interference from transgenic hFSH. The greatly enhanced sensitivity, specificity, and technical convenience of this mFSH IFMA will allow wider application of FSH measurements to very small blood samples in immature and mature mice as well as transgenic models.

Pharmacokinetic aspects of biotechnology products

In recent years, biotechnologically derived peptide and protein-based drugs have developed into mainstream therapeutic agents. Peptide and protein drugs now constitute a substantial portion of the compounds under preclinical and clinical development in the global pharmaceutical industry. Pharmacokinetic and exposure/response evaluations for peptide and protein therapeutics are frequently complicated by their similarity to endogenous peptides and proteins as well as protein nutrients. The first challenge frequently comes from a lack of sophistication in various analytical techniques for the quantification of peptide and protein drugs in biological matrices. However, advancements in bioassays and immunoassays--along with a newer generation of mass spectrometry-based techniques--can often provide capabilities for both efficient and reliable detection. Selection of the most appropriate route of administration for biotech drugs requires comprehensive knowledge of their absorption characteristics beyond physicochemical properties, including chemical and metabolic stability at the absorption site, immunoreactivity, passage through biomembranes, and active uptake and exsorption processes. Various distribution properties dictate whether peptide and protein therapeutics can reach optimum target site exposure to exert the intended pharmacological response. This poses a potential problem, especially for large protein drugs, with their typically limited distribution space. Binding phenomena and receptor-mediated cellular uptake may further complicate this issue. Elimination processes--a critical determinant for the drug's systemic exposure--may follow a combination of numerous pathways, including renal and hepatic metabolism routes as well as generalized proteolysis and receptor-mediated endocytosis. Pharmacokinetic/pharmacodynamic (PK/PD) correlations for peptide and protein-based drugs are frequently convoluted by their close interaction with endogenous substances and physiologic regulatory feedback mechanisms. Extensive use of pharmacokinetic and exposure/response concepts in all phases of drug development has in the past been identified as a crucial factor for the success of a scientifically driven, evidence-based, and thus accelerated drug development process. Thus, PK/PD concepts are likely to continue and expand their role as a fundamental factor in the successful development of biotechnologically derived drug products in the future.

Luteinizing hormone estimation

Luteinizing hormone (LH) is an important hormone of the reproductive system, which has found application in diagnosis and therapeutic medicine. It plays a vital role in the development and functioning of the reproductive system. Determination of LH concentration is important for detection of dysfunction of the pituitary-ovarian axis, diagnosis of reproductive disorders, monitoring of antifertility programmes and in therapeutic preparations. On the basis of heterogeneity and various biological effects served by the hormone, different assay systems have been developed for its estimation. Initially, LH was quantified on the basis of in vivo and in vitro endocrine activity. However, with the advancement in biotechnology, various immunoassays have been designed for performing most of the physiological and clinical studies on serum LH. The immunoassays offer improvement in sensitivity, precision and convenience over bioassays. However, these immunoassays have their own limitations and results obtained in different laboratories are often not comparable. This review makes an attempt to enumerate and compare various assay methods used in the serum LH measurement in varied clinical conditions.

Reliability of follicle-stimulating hormone measurements in serum

BACKGROUND

Follicle-stimulating hormone (FSH), a member of gonadotropin family, is critical for follicular maturation and ovarian steroidogenesis. Serum FSH levels are known to fluctuate during different phases of menstrual cycle in premenopausal women, and increase considerably after the menopause as a result of ovarian function cessation. There is little existing evidence to guide researchers in estimating the reliability of serum FSH measurements. The objective of this study was to assess the reliability of FSH measurement using stored sera from an ongoing prospective cohort--the NYU Women's Health Study.

METHODS

Sixty healthy women (16 premenopausal, 44 postmenopausal), who donated at least two blood samples at approximately 1-year intervals were studied. An immunoradiometric assay using a sandwich monoclonal antibodies technique was used to measure FSH levels in serum.

RESULTS

The reliability of a single log-transformed FSH measurement, as determined by the intraclass correlation coefficient, was 0.70 for postmenopausal women (95% confidence interval (CI), 0.55-0.82) and 0.09 for premenopausal women (95% CI, 0-0.54).

CONCLUSIONS

These results suggest that a single measurement is sufficient to characterize the serum FSH level in postmenopausal women and could be a useful tool in epidemiological research. For premenopausal women, however, the reliability coefficient was low, suggesting that a single determination is insufficient to reliably estimate a woman's true average serum FSH level and repeated measurements are desirable.

Characterization of human FSH isoforms reveals a nonglycosylated beta-subunit in addition to the conventional glycosylated beta-subunit

Human FSH consists of a mixture of isoforms that can be separated on the basis of differences in negative charge conferred by variations in the numbers of sialic acid residues that terminate oligosaccharide branches. Western analysis of human FSH isoforms separated by chromatofocusing revealed the presence of two human FSHbeta isoforms that differed in size. A low mol wt human FSHbeta isoform was associated with all FSH isoform fractions. A high mol wt human FSHbeta isoform was associated with the more acidic fractions and increased in relative abundance as the pI decreased. Characterization of representative human FSHbeta isoforms by mass spectrometry and automated Edman degradation revealed a low mol wt isoform that was not glycosylated. A high mol wt isoform was N-glycosylated at Asn residues 7 and 24. These results indicate that pituitary human FSH consists of two classes of molecules: those that possess a nonglycosylated beta-subunit and those that possess a glycosylated beta-subunit. Glycoprotein hormones are known to be elliptical molecules, and the beta-subunit oligosaccharides project outward from the short diameter, thereby increasing it. It is interesting to speculate that this change in shape might affect ultrafiltration rates, leading to differences in delivery rates to target tissues and elimination by filtration in the kidney.