Kisspeptin Neurons and Estrogen-Estrogen Receptor α Signaling: Unraveling the Mystery of Steroid Feedback System Regulating Mammalian Reproduction

Estrogen produced by ovarian follicles plays a key role in the central mechanisms controlling reproduction via regulation of gonadotropin-releasing hormone (GnRH) release by its negative and positive feedback actions in female mammals. It has been well accepted that estrogen receptor α (ERα) mediates both estrogen feedback actions, but precise targets had remained as a mystery for decades. Ever since the discovery of kisspeptin neurons as afferent ERα-expressing neurons to govern GnRH neurons, the mechanisms mediating estrogen feedback are gradually being unraveled. The present article overviews the role of kisspeptin neurons in the arcuate nucleus (ARC), which are considered to drive pulsatile GnRH/gonadotropin release and folliculogenesis, in mediating the estrogen negative feedback action, and the role of kisspeptin neurons located in the anteroventral periventricular nucleus-periventricular nucleus (AVPV-PeN), which are thought to drive GnRH/luteinizing hormone (LH) surge and consequent ovulation, in mediating the estrogen positive feedback action. This implication has been confirmed by the studies showing that estrogen-bound ERα down- and up-regulates kisspeptin gene (Kiss1) expression in the ARC and AVPV-PeN kisspeptin neurons, respectively. The article also provides the molecular and epigenetic mechanisms regulating Kiss1 expression in kisspeptin neurons by estrogen. Further, afferent ERα-expressing neurons that may regulate kisspeptin release are discussed.

Effect of chronological age of patients with diminished ovarian reserve on in vitro fertilization outcome

The aim of this study was to evaluate the effect of chronological age on the in vitro fertilization (IVF) outcome in patients with diminished ovarian reserve (DOR). Four hundred and forty-nine women with DOR who underwent IVF cycles were enrolled in the study. There were only 296 patients who obtained available embryos. The patients with no available embryos had a significantly lower antral follicle count (AFC) and higher basal follicle-stimulating hormone (FSH) concentrations than those of women with available embryos, but chronological age in the two groups was comparable. However, patients aged >40 obtained a significantly lower ongoing pregnancy rate (OPR) than patients aged 35 - 40 or <35 (6.38% versus 26.15% versus 28.17%, respectively). Multivariate analysis also showed that chronological age was the only parameter associated with clinical results. It implied that patients with DOR still have reasonable chances of achieving a pregnancy, but their prognosis is significantly affected by chronological age.Impact statementWhat is already known on this subject? Diminished ovarian reserve DOR is a disappointing issue in reproductive medicine. Ovarian reserve, which represents ovarian biological age, is closely related to chronological age. However, ovarian biological age does not always match chronological age. Some studies suggest that biological age is more important than chronological age in predicting the outcome of in vitro fertilization (IVF). However, these conclusions are controversial.What do the results of this study add? We found DOR patients with no available embryos had significantly lower antral follicle count (AFC) and higher follicle-stimulating hormone (FSH) concentrations than that of patients with available embryos, but chronological age in the two groups was comparable. However, for patients with available embryos, chronological age is the only parameter associated with clinical results. For women aged >40 with DOR, chronological age was significantly negatively associated with clinical results.What are the implications of these findings for clinical practice and/or further research? Patients with DOR can obtain available embryos and still have a reasonable chance of becoming pregnant, but their prognosis is greatly affected by chronological age. Therefore, patients with DOR should seek medical help for pregnancy as soon as possible. When DOR patients over the age of 40 plan IVF treatment, the cost-effectiveness of healthcare should be considered.

Follicle-stimulating hormone (FSH) levels prior to prostatectomy are not related to long-term oncologic or cardiovascular outcomes for men with prostate cancer

Prior research suggests a link between circulating levels of follicle-stimulating hormone (FSH) and prostate cancer outcomes. FSH levels may also explain some of the observed differences in cardiovascular events among men treated with gonadotropin-releasing hormone (GnRH) antagonists compared to GnRH agonists. This study evaluates the association between preoperative FSH and long-term cardiovascular and oncologic outcomes in a cohort of men with long follow-up after radical prostatectomy. We performed a cohort study utilizing an institutional biobank with annotated clinical data. FSH levels were measured from cryopreserved plasma and compared with sex steroids previously measured from the same samples. Differences in oncologic outcomes between tertiles of FSH levels were compared using adjusted cox regression models. Major adverse cardiovascular events (MACE) were similarly assessed using hospital admission diagnostic codes. A total of 492 patients were included, with a median follow-up of 13.1 (interquartile range: 8.9–15.9) years. Dehydroepiandrosterone sulfate (DHEA-S) levels, but not other androgens, negatively correlated with FSH levels on linear regression analysis (P = 0.03). There was no association between FSH tertile and outcomes of biochemical recurrence, time to castrate-resistant prostate cancer, or time to metastasis. MACEs were identified in 50 patients (10.2%), with a mean time to first event of 8.8 years. No association with FSH tertile and occurrence of MACE was identified. Our results do not suggest that preoperative FSH levels are significantly associated with oncologic outcomes among prostate cancer patients treated with radical prostatectomy, nor do these levels appear to be predictors of long-term cardiovascular risk.

Effects of LPXRFamide peptides on chub mackerel gonadotropin secretion

Gonadotropin-inhibitory hormone (GnIH), a neuropeptide, suppresses gonadotropin (GTH) secretion in birds and mammals. In fish, the GnIH homolog LPXRFamide (LPXRFa) produces mature peptides with species-dependent effects on sexual reproduction. Here, we investigated the effects of LPXRFa on GTH secretion in the chub mackerel (cm; Scomber japonicus). We cloned cmlpxrfa (603 bp) and cmlpxrfa-r (1,416 bp). Additionally, we isolated lpxrfa from the bluefin tuna (Thunnus orientalis) to confirm the conservation of the LPXRFa mature sequence. Phylogenetic analysis showed that the LPXRFa precursor protein produces three mature peptides, LPXRFa-1, -2, and - 3, in both species. Reverse transcription-quantitative PCR revealed that cmlpxrfa is expressed in the hypothalamus and thalamus and midbrain (T.MB), and sexual differences were observed. Receptor expression was observed in the pre-optic area, hypothalamus, T.MB, and pituitary. Female hypothalamic lpxrfa expression did not change during puberty. Reporter gene assay showed that LPXRFa induced receptor activation via the CRE and SRE signaling pathways. However, in the presence of forskolin, an intracellular cyclic AMP enhancer, none of the LPXRFa could suppress receptor activity. The in vitro bioassay results showed that gonadotropin-releasing hormone-1 (GnRH1) had no effect on follicle-stimulating hormone (FSH) secretion, whereas the three LPXRFa significantly increased FSH secretion in pituitary cells from male chub mackerel. Contrarily, GnRH1 and three LPXRFa significantly increased luteinizing hormone (LH) secretion. The in vivo administration of LPXRFa had no effect on fshb and lhb expression in pre-pubertal and mature male chub mackerel. Overall, cmLPXRFa lacks the ability to suppress GTH secretion but can promote GTH secretion.

Follicle-stimulating hormone worsens osteoarthritis by causing inflammation and chondrocyte dedifferentiation

Previous studies have found follicle‐stimulating hormone (FSH) receptors on chondrocytes (cartilage cells), but the mechanism of FSH action on chondrocytes is not clear. The purpose of this experiment is to study whether FSH affects chondrocytes and how it causes changes in these cells. Our results show that osteoarthritis became worse after FSH injection in the knee joint of mice. After the stimulation of chondrocytes by FSH, a total of 664 up‐regulated genes, such as Col12a1 and Col1a1, and 644 down‐regulated genes, such as MGP, were screened by transcriptomics. A subset of extracellular matrix (ECM)‐related genes and pathways underwent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and the downregulation of MGP, the upregulation of EGR1 and Col1a1, and the increase of IL‐6 were verified. It was also observed that FSH can inhibit the cAMP/PKA and MKK4/JNK signaling pathway. In conclusion, we demonstrated that FSH can increase cartilage inflammatory response and promote chondrocyte dedifferentiation by inhibiting the cAMP/PKA and MKK4/JNK signaling pathways.

FSH dosage effect on conventional sperm parameters: a meta-analysis of randomized controlled studies

Follicle-stimulating hormone (FSH) represents a therapeutic option in normogonadotropic patients with idiopathic oligozoospermia. The aim of this review was to evaluate the possible dose- and drug-dependent efficacy of FSH treatment on conventional sperm parameters. We performed a comprehensive systematic review via a meta-analysis of all available randomized controlled trials, in which FSH administration was compared with placebo or no treatment when administered to normogonadotropic patients with idiopathic oligozoospermia. Of the 971 articles that were retrieved, 5 were finally included, including a total of 372 patients and 294 controls. Overall, FSH treatment was effective in ameliorating the sperm concentration, total count, progressive motility, but not normal forms. On the basis of the weekly dosage, the studies were classified into those using low (175–262.5 IU per week), intermediate (350–525 IU per week), and high (700–1050 IU per week) doses. At low doses, FSH improved only sperm motility. At intermediate doses, FSH ameliorated sperm concentration and morphology. Total sperm count and progressive motility showed a trend toward the increase. At high doses, FSH increased sperm concentration, total sperm count, and progressive motility. Sperm morphology showed a trend toward the increase. Finally, both highly purified FSH (hpFSH) and recombinant human FSH (rhFSH) improved sperm concentration, total sperm count, progressive motility, but not morphology. No different efficacy was observed between these two preparations. This meta-analysis provides evidence in favor of high FSH doses. The FSH efficacy was not related to the preparation type (recombinant vs highly purified). Further studies are needed to evaluate the effectiveness of long-standing treatment regimes.

Morphology and Biochemistry of Ovulation

The process of ovulation involves multiple and iterrelated genetic, biochemical, and morphological events: cessation of the proliferation of granulosa cells, resumption of oocyte meiosis, expansion of cumulus cell-oocyte complexes, digestion of the follicle wall, and extrusion of the metaphase-II oocyte. The present narrative review examines these interrelated steps in detail. The combined or isolated roles of the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are highlighted. Genes indiced by the FSH genes are relevant in the cumulus expansion, and LH-induced genes are critical for the resumption of meiosis and digestion of the follicle wall. A non-human model for follicle-wall digestion and oocyte release was provided.

Effect of varicocele repair on sperm retrieval rate and testicular histopathological patterns in men with nonobstructive azoospermia

Varicocele adversely affects semen parameters. However, the effect of varicocele repair on the sperm retrieval rate and testicular histopathological patterns in men with nonobstructive azoospermia has not been widely reported. We retrospectively assessed the sperm retrieval rates and testicular histopathological patterns in men with nonobstructive azoospermia who were referred to the Urology Clinic in Dr. Cipto Mangunkusumo Hospital (Jakarta, Indonesia) and Bunda General Hospital (Jakarta, Indonesia) between January 2009 and December 2019. We compared patients who had undergone a surgical sperm retrieval procedure for assisted reproductive technology no earlier than three months after varicocele repair and those who had not undergone varicocele repair. The study included 104 patients (age range: 26-54 years), 42 of whom had undergone varicocele repair before the sperm retrieval procedure and 62 who had not. Motile spermatozoa were found in 29 (69.1%) and 17 (27.4%) patients who had undergone varicocele repair before the sperm retrieval procedure and those who had not undergone the repair, respectively (relative risk: 2.51; 95% confidence interval: 1.60-3.96; P < 0.001). A predicted probabilities graph showed consistently higher sperm retrieval rates for patients with varicocele repair, regardless of their follicle-stimulating hormone levels. Patients who underwent varicocele repair showed higher testicular histopathological patterns (P = 0.001). In conclusion, men with nonobstructive azoospermia and clinical varicocele who underwent varicocele repair before the sperm retrieval procedure had higher sperm retrieval rates compared to those who did not undergo varicocele repair.

Spontaneous ovarian hyperstimulation syndrome in a nonpregnant female patient: a case report and literature review

Spontaneous ovarian hyperstimulation syndrome (sOHSS) usually occurs in patients with a spontaneous ovulation cycle, especially in those with multiple pregnancies combined with hypothyroidism and polycystic ovary syndrome. sOHSS rarely occurs in women who are not pregnant. A 23-year-old woman with obvious abdominal distension visited our hospital. The patient was not pregnant and had not undergone controlled superovulation. Apart from abdominal distension, the patient denied any symptom of obvious incentives, abdominal pain, abnormal vaginal bleeding, or drainage. Biochemical analysis showed a high carbohydrate antigen-125 level and low total protein and albumin levels. Abdominal ultrasound and computed tomography showed a large amount of ascites and cystic uneven masses with an irregular shape in the area of the ovaries and fallopian tubes. Post-surgical histopathology indicated the diagnosis of sOHSS. Wedge resection of both ovaries was performed. Symptomatic treatment was further performed and the patient recovered well. Our findings indicate that sOHSS can occur in women who are not pregnant. Additionally, besides the follicle-stimulating hormone receptor gene mutation hypothesis, the pathogenesis of sOHSS should be further studied.

The Luteinizing Hormone Receptor Knockout Mouse as a Tool to Probe the In Vivo Actions of Gonadotropic Hormones/Receptors in Females

Mouse models with altered gonadotropin functions have provided invaluable insight into the functions of these hormones/receptors. Here we describe the repurposing of the infertile and hypogonadal luteinizing hormone receptor (LHR) knockout mouse model (LuRKO), to address outstanding questions in reproductive physiology. Using crossbreeding strategies and physiological and histological analyses, we first addressed the physiological relevance of forced LHR homomerization in female mice using BAC expression of 2 ligand-binding and signaling deficient mutant LHR, respectively, that have previously shown to undergo functional complementation and rescue the hypogonadal phenotype of male LuRKO mice. In female LuRKO mice, coexpression of signaling and binding deficient LHR mutants failed to rescue the hypogonadal and anovulatory phenotype. This was apparently due to the low-level expression of the 2 mutant LHR and potential lack of luteinizing hormone (LH)/LHR-dependent pleiotropic signaling that has previously been shown at high receptor densities to be essential for ovulation. Next, we utilized a mouse model overexpressing human chorionic gonadotropin (hCG) with increased circulating "LH/hCG"-like bioactivity to ~40 fold higher than WT females, to determine if high circulating hCG in the LuRKO background could reveal putative LHR-independent actions. No effects were found, thus, suggesting that LH/hCG mediate their gonadal and non-gonadal effects solely via LHR. Finally, targeted expression of a constitutively active follicle stimulating hormone receptor (FSHR) progressed antral follicles to preovulatory follicles and displayed phenotypic markers of enhanced estrogenic activity but failed to induce ovulation in LuRKO mice. This study highlights the critical importance and precise control of functional LHR and FSHR for mediating ovarian functions and of the potential repurposing of existing genetically modified mouse models in answering outstanding questions in reproductive physiology.

The combination of Elephantopus scaber and Sauropus androgynus promotes erythroid lineages and modulates follicle-stimulating hormone and luteinizing hormone levels in pregnant mice infected with Escherichia coli

BACKGROUND AND AIM

Escherichia coli infection produces an adverse effect on the erythrocyte lineage and hormone levels during pregnancy. This study aimed to evaluate the effects of Elephantopus scaber (ES) and Sauropus androgynus (SA) in combination on circulating follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels and erythropoiesis changes in E. coli-infected pregnant mice.

MATERIALS AND METHODS

Female Balb/c mice were mated with normal male mice and pregnancies were identified by the formation of vaginal plugs. Twenty-eight pregnant mice were divided randomly into seven groups: A control group (N), E. coli-infected pregnant mice (K+), and infected pregnant mice received the following five treatments: (1) Only ES; (2) ESSA1 (75:25); (3) ESSA2 (50:50); (4) ESSA3 (25:75); and (5) only SA, beginning from the 1st to the 16th day of pregnancy. Pregnant mice were infected with 107 CFU/mL of E. coli on day 4. Blood serum was collected on days 8, 12, and 16 of pregnancy and LH and FSH levels were measured by enzyme-linked immunosorbent assay. Bone marrow was isolated to determine the relative number of TER-119+VLA4+ and TER-119+CD34+ using flow cytometry.

RESULTS

The ESSA1 and SA groups exhibited a marked increase in LH levels. The combination of ES and SA administered at a 25:75 ratio (ESSA3) altered FSH levels and the relative number of TER-119+VLA4+ in infected pregnant mice. Combined with SA at an equal ratio (50:50), ESSA2 group exhibited a significant increase in the expression of TER119+CD34+ compared with the other treatment groups.

CONCLUSION

ES and SA combined at a ratio of 25:75 exhibited optimal results in altering hormonal and erythropoiesis in infected pregnant mice.

The patterns and occupational distribution of hormonal abnormalities among men investigated for infertility in some centers in the southwest, Nigeria

BACKGROUND AND AIM

Male factor infertility results from dysfunction at various levels of spermatogenesis, sex hormone abnormalities, and occupation or workplace exposure to toxins are involved. This study was designed to determine the frequency of occupational distribution of men who were evaluated for infertility, the patterns of hormonal abnormalities, and to associate hormonal abnormalities with occupational categories in some centers in Osun State, Nigeria.

METHODS

Semen and 5 mL of whole blood were collected from the infertile men (n=319) who were referred to the laboratories for fertility investigation after physical and medical examination. Semen analysis was performed microscopically according to the World Health Organization manual while serum gonadotrophin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and prolactin were determined by Enzyme-linked Immunosorbent assay technique using reagents supplied by Biorex Diagnostics Limited, Antrim, United Kingdom. The subjects were grouped based on semen characteristics.

RESULTS

More than half 164 (51.4%) of the subjects were within the age group of 31-40 years, followed by 70 (21.9%) in the age group of 21-30 years, while 67 (21.0%) was in the age group of 41-50 years. Some 133/319 (41.7%) of the subjects had normal sex hormone levels while 186/319 (58.3%) had abnormal hormone levels. The patterns of hormonal abnormalities observed were 96/186 (51.6%) normogonadotrophin-hypogonadism, 49/186 (26.3%) normogonadotrophin-hypergonadism, 14/186 (7.5%) elevated FSH levels, 15/186 (8.1%) elevated LH levels, 07/186 (3.8%) hypergonadotropic-hypergonadism, and 05/186 (2.7%) hyperprolactinemia. Artisans (OR 1.2252 95%CI 0.367-2.472), workers in chemical related industries (OR 1.667, 95%CI 0.594-4.676), and businessmen (OR 1.200, 95%CI 0.110-3.49) are more likely to be predisposed to hormonal abnormalities.

CONCLUSION

The patterns of hormone abnormalities as well as their relative proportions are slightly different from those reported previously. Some occupations may predispose workers to hormonal disorder than the others.

RELEVANCE FOR PATIENTS

This is a cross-sectional study of males investigated for infertility; the contribution and patterns of hormonal abnormalities were evaluated. The possible association between workplace and infertility that may assist in the management of patients with male infertility was evaluated.

A novel PPRC1 point mutation in a Chinese family with premature ovarian failure: A case study

BACKGROUND

Patients with premature ovarian failure (POF) have an at least 6-month history of amenorrhea and elevated follicle-stimulating hormone levels in plasma. Most of the POF causes are idiopathic and hereditary, and chromosomal abnormalities have been associated with POF development. A pedigree study was performed on a family with idiopathic POF to observe the possible link between gene mutation and POF development.

METHODS

In total, eight women were diagnosed with POF and seven POF patients and five non-POF members from the same family were evaluated by whole exome sequencing and Sanger sequencing. An apoptotic assay, senescence staining, real-time polymerase chain reaction (qPCR) and overexpression of the peroxisome proliferator-activated receptor gamma coactivator-related 1 (PPRC1) gene were performed to examine the association of POF in vitro.

RESULTS

Through whole exome sequencing and Sanger sequencing, a novel point mutation (NM_015062: c.2902C>T:p.Thr958Ile) was identified and verified in the PPRC1 gene on chromosome 10 (10q24.32). The point mutation only presented in all the seven POF cases and not in non-POF cases or public databases. Subsequent expression of PPRC1 in COV434 granulosa cells showed that PPRC1 might be involved in regulating granulosa cell apoptosis but not senescence-associated POF development.

CONCLUSIONS

A novel point mutation in the PPRC1 gene was identified by the pedigree study and by sequence analysis of the case series with idiopathic POF in the present study. The subsequent PPRC1 expression analysis showed that PPRC1 was not involved in senescence-associated POF development. Further studies will be needed to confirm the link between PPRC1 gene mutation and POF.

Advances in the Regulation of Mammalian Follicle-Stimulating Hormone Secretion

Simple Summary

The reproduction of mammals is regulated by the hypothalamic-pituitary-gonadal axis. Follicle stimulating hormone, as one of the gonadotropins secreted by the pituitary gland, plays an immeasurable role. This article mainly reviews the molecular basis and classical signaling pathways that regulate the synthesis and secretion of follicle stimulating hormone, and summarizes its internal molecular mechanism, which provides a certain theoretical basis for the research of mammalian reproduction regulation and the application of follicle stimulating hormone in production practice.

Abstract

Mammalian reproduction is mainly driven and regulated by the hypothalamic-pituitary-gonadal (HPG) axis. Follicle-stimulating hormone (FSH), which is synthesized and secreted by the anterior pituitary gland, is a key regulator that ultimately affects animal fertility. As a dimeric glycoprotein hormone, the biological specificity of FSH is mainly determined by the β subunit. As research techniques are being continuously innovated, studies are exploring the underlying molecular mechanism regulating the secretion of mammalian FSH. This article will review the current knowledge on the molecular mechanisms and signaling pathways systematically regulating FSH synthesis and will present the latest hypothesis about the nuclear cross-talk among the various endocrine-induced pathways for transcriptional regulation of the FSH β subunit. This article will provide novel ideas and potential targets for the improved use of FSH in livestock breeding and therapeutic development.

Follicle-stimulating hormone promotes growth of human prostate cancer cell line-derived tumor xenografts

Chemical castration in prostate cancer can be achieved with gonadotropin-releasing hormone (GnRH) agonists or antagonists. Their effects differ by the initial flare of gonadotropin and testosterone secretion with agonists and the immediate pituitary-testicular suppression by antagonists. While both suppress luteinizing hormone (LH) and follicle-stimulating hormone (FSH) initially, a rebound in FSH levels occurs during agonist treatment. This rebound is potentially harmful, taken the expression of FSH receptors (R) in prostate cancer tissue. We herein assessed the role of FSH in promoting the growth of androgen-independent (PC-3, DU145) and androgen-dependent (VCaP) human prostate cancer cell line xenografts in nude mice. Gonadotropins were suppressed with the GnRH antagonist degarelix, and effects of add-back human recombinant FSH were assessed on tumor growth. All tumors expressed GnRHR and FSHR, and degarelix treatment suppressed their growth. FSH supplementation reversed the degarelix-evoked suppression of PC-3 tumors, both in preventive (degarelix and FSH treatment started upon cell inoculation) and therapeutic (treatments initiated 3 weeks after cell inoculation) setting. A less marked, though significant FSH effect occurred in DU145, but not in VCaP xenografts. FSHR expression in the xenografts supports direct FSH stimulation of tumor growth. Testosterone supplementation, to maintain the VCaP xenografts, apparently masked the FSH effect on their growth. Treatment with the LH analogue hCG did not affect PC-3 tumor growth despite their expression of luteinizing hormone/choriongonadotropin receptor. In conclusion, FSH, but not LH, may directly stimulate the growth of androgen-independent prostate cancer, suggesting that persistent FSH suppression upon GnRH antagonist treatment offers a therapeutic advantage over agonist.

Age-specific reference intervals of serum anti-Müllerian hormone in Chinese girls

BACKGROUND

This study aimed to establish anti-Mullerian hormone age-specific reference intervals and determine the correlation between the anti-Mullerian hormone concentration and age, body mass index and concentrations of follicle-stimulating hormones and luteinizing hormone in healthy Chinese girls.

METHODS

Serum anti-Mullerian hormone concentrations of 1702 healthy girls (0-12 years), recruited between March 2018 and December 2019, were determined using the Beckman Access 2 automated chemiluminescence immunoassay. Single-year-specific medians of anti-Mullerian hormone and effects of age, body mass index, follicle-stimulating hormone and luteinizing hormone on anti-Mullerian hormone concentration were analysed.

RESULTS

The anti-Mullerian hormone median level continued increasing from birth, reached its peak at age 9 at 4.45 ng/mL (interquartile range [IQR] 2.58-6.90) and then gradually decreased. At age 12, the median reached 1.98 ng/mL (IQR 1.05-3.46). Age-specific reference intervals for anti-Mullerian hormone were established in healthy Chinese girls aged 0-12 years. Anti-Mullerian hormone concentrations showed a moderately positive correlation with age (r = 0.33, P < 0.001). In contrast, follicle-stimulating hormone (r = -0.29, P < 0.001) concentrations were weakly negatively correlated with the serum anti-Mullerian hormone concentration.

CONCLUSION

We established single-year-specific reference intervals for anti-Mullerian hormone in Chinese girls using the Beckman chemiluminescent platform. This reference range can help clinicians accurately understand anti-Mullerian hormone secretion in healthy girls and promote its clinical use.

Levels of Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), Testosterone and Prolactin at Moderate Altitude Inhabitant Male

BACKGROUND AND OBJECTIVE

Male fertility depends on the availability of the potent androgen called testosterone. Testosterone production is regulated by the hypothalamic anterior pituitary axis. Two anterior pituitary hormones Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) are involved in spermatogenesis and testosterone production, respectively. Hypoxia, resulting from high altitude, may induce a change in these four hormones and may affect male fertility. This study was done to evaluate and compare the changes that occur in FSH, LH, testosterone and prolactin in males lived in moderate versus low altitude.

MATERIALS AND METHODS

This study was conducted on 300 individuals who were categorized based on the altitude of their habitat into two equal groups, namely: Inhabitants at moderate altitudes and inhabitants at low altitudes. A venous blood sample was collected from each individual to measure the levels of FSH, LH and prolactin.

RESULTS

Both LH and testosterone levels were significantly lower in high altitude inhabitants compared with low altitude inhabitants (p<0.01). The FSH level showed a significant statistical difference between two groups with a lower level in individuals living at high altitudes compared with low altitude inhabitants but on a value (p<0.05).

CONCLUSION

Moderate altitude hypoxia suppresses LH, FSH and testosterone levels as much as high altitude hypoxia does and these changes may depend on prolactin level.

Occupational use of agrochemicals results in inhibited cholinesterase activity and altered reproductive hormone levels in male farmers from Buea, Cameroon

The efficiency of agro pesticides and fertilizers in eliminating pests and scaling up crop yield has motivated farmers to increase their use. Unfortunately, health hazards caused on farmers by these agrochemicals are of growing concern, though not well elucidated. In order to evaluate the effects of occupational exposure to agrochemicals on some key parameters of male farmers' health in Buea Subdivision, Cameroon, a total of 101 men, including 62 farmers using the agrochemicals and a reference population of 39 men not involved in occupational utilization of the agrochemicals, were interviewed on use of protective equipment, exposure symptoms and reproductive health status. Thereafter, serum cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)] activities, total antioxidant capacity and reproductive hormones [follicle-stimulating hormone (FSH), luteinizing hormone and testosterone] were assessed. Results revealed that farmers mainly used insecticides followed by fungicides, herbicides and fertilizers, but with inadequate protective measures. The use of agrochemicals resulted in several exposure symptoms including weakness, itches, burning sensation, headache, sneezing, coughing and vomiting, as well as decrease in serum AChE activity when compared to the reference population. The agrochemicals impacted negatively on the farmers' reproductive health as evidenced by increased FSH levels. Taken altogether, these results suggested that exposure to agrochemicals adversely affects farmers' health. Therefore, there is a need to further sensitize the farmers on the use of protective equipment to mitigate the exposure and resulting health hazards.

Effects of Vitamin D Supplementation on Surrogate Markers of Fertility in PCOS Women: A Randomized Controlled Trial

Vitamin D (VD) might play an important role in polycystic ovary syndrome (PCOS) and female fertility. However, evidence from randomized controlled trials (RCT) is sparse. We examined VD effects on anti-Müllerian hormone (AMH) and other endocrine markers in PCOS and non-PCOS women. This is a post hoc analysis of a single-center, double-blind RCT conducted between December 2011 and October 2017 at the endocrine outpatient clinic at the Medical University of Graz, Austria. We included 180 PCOS women and 150 non-PCOS women with serum 25-hydroxyvitamin D (25(OH)D) concentrations <75 nmol/L in the trial. We randomized subjects to receive 20,000 IU of VD3/week (119 PCOS, 99 non-PCOS women) or placebo (61 PCOS, 51 non-PCOS women) for 24 weeks. Outcome measures were AMH, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, dehydroepiandrosterone sulfate, and androstenedione. In PCOS women, we observed a significant treatment effect on FSH (mean treatment effect 0.94, 95% confidence interval [CI] 0.087 to 1.799, p = 0.031) and LH/FSH ratio (mean treatment effect −0.335, 95% CI −0.621 to 0.050, p = 0.022), whereas no significant effect was observed in non-PCOS women. In PCOS women, VD treatment for 24 weeks had a significant effect on FSH and LH/FSH ratio but no effect on AMH levels.

FSH directly regulates chondrocyte dedifferentiation and cartilage development

Previous studies suggest that postmenopausal osteoarthritis is linked to a decrease in estrogen levels. However, whether follicle-stimulating hormone (FSH), the upstream hormone of estrogen, affects cartilage destruction and thus contributes to the onset of osteoarthritis has never been explored. To evaluate the potential involvement of FSH in joint degeneration and to identify the molecular mechanisms through which FSH influences chondrocytes, mouse cartilage chondrocytes and the ATDC5 chondrocyte cell line were treated with FSH and inhibitors of intracellular signaling pathways. We observed that FSH induces chondrocyte dedifferentiation by decreasing type II collagen (Coll-II) synthesis. Chondrocyte cytoskeleton reorganization was also observed after FSH treatment. The FSH-induced decrease in Coll-II was rescued by ERK-1/2 inhibition but aggravated by p38 inhibition. In addition, knocking down the FSH receptor (Fshr) by using Fshr siRNA abolished chondrocyte dedifferentiation, as indicated by the increased expression of Coll-II. Inhibition of the protein Gαi by pertussis toxin (PTX) also restored FSH-inhibited Coll-II, suggesting that Gαi is downstream of FSHR in chondrocyte dedifferentiation. FSHβ antibody blockade prevented cartilage destruction and cell loss in mice. Moreover, decreased Coll-II staining due to the progression of aging could be rescued by blocking FSH. Thus, we suggest that high circulating FSH, independent of estrogen, is an important regulator in chondrocyte dedifferentiation and cartilage destruction.

A Novel Mutation in the FSH Receptor (I423T) Affecting Receptor Activation and Leading to Primary Ovarian Failure

CONTEXT

Follicle-stimulating hormone (FSH) plays an essential role in gonadal function. Loss-of-function mutations in the follicle-stimulating hormone receptor (FSHR) are an infrequent cause of primary ovarian failure.

OBJECTIVE

To analyze the molecular physiopathogenesis of a novel mutation in the FSHR identified in a woman with primary ovarian failure, employing in vitro and in silico approaches, and to compare the features of this dysfunctional receptor with those shown by the trafficking-defective D408Y FSHR mutant.

METHODS

Sanger sequencing of the FSHR cDNA was applied to identify the novel mutation. FSH-stimulated cyclic adenosine monophosphate (cAMP) production, ERK1/2 phosphorylation, and desensitization were tested in HEK293 cells. Receptor expression was analyzed by immunoblotting, receptor-binding assays, and flow cytometry. Molecular dynamics simulations were performed to determine the in silico behavior of the mutant FSHRs.

RESULTS

A novel missense mutation (I423T) in the second transmembrane domain of the FSHR was identified in a woman with normal pubertal development but primary amenorrhea. The I423T mutation slightly impaired plasma membrane expression of the mature form of the receptor and severely impacted on cAMP/protein kinase A signaling but much less on β-arrestin-dependent ERK1/2 phosphorylation. Meanwhile, the D408Y mutation severely affected membrane expression, with most of the FSH receptor located intracellularly, and both signal readouts tested. Molecular dynamics simulations revealed important functional disruptions in both mutant FSHRs, mainly the loss of interhelical connectivity in the D408Y FSHR.

CONCLUSIONS

Concurrently, these data indicate that conformational differences during the inactive and active states account for the distinct expression levels, differential signaling, and phenotypic expression of the I423T and D408Y mutant FSHRs.

Endocrine Fertility Parameters-Genomic Background and their Genetic Relationship to Boar Taint in German Landrace and Large White

The surgical castration of young male piglets without anesthesia is no longer allowed in Germany from 2021. One alternative is breeding against boar taint, but shared synthesis pathways of androstenone (AND) and several endocrine fertility parameters (EFP) indicate a risk of decreasing fertility. The objective of this study was to investigate the genetic background between AND, skatole (SKA), and six EFP in purebred Landrace (LR) and Large White (LW) populations. The animals were clustered according to their genetic relatedness because of their different origins. Estimated heritabilities (h²) of AND and SKA ranged between 0.52 and 0.34 in LR and LW. For EFP, h² differed between the breeds except for follicle-stimulating hormone (FSH) (h²: 0.28-0.37). Both of the breeds showed unfavorable relationships between AND and testosterone, 17-β estradiol, and FSH. The genetic relationships (r_g) between SKA and EFP differed between the breeds. A genome-wide association analysis revealed 48 significant associations and confirmed a region for SKA on S us S crofa chromosome (SSC) 14. For EFP, the results differed between the clusters. In conclusion, r_g partly confirmed physiologically expected antagonisms between AND and EFP. Particular attention should be spent on fertility traits that are based on EFP when breeding against boar taint to balance the genetic progress in both of the trait complexes.

Cadmium Exposure and Ovarian Reserve in Women Aged 35-49 Years: The Impact on Results From the Creatinine Adjustment Approach Used to Correct for Urinary Dilution

Cadmium is toxic to the ovaries in animal studies, but its association with diminished ovarian reserve in women is not established. We investigated urinary cadmium, a biomarker of long-term exposure, in relation to diminished ovarian reserve, as indicated by elevated serum follicle-stimulating hormone concentrations (≥10 IU/L), in women aged 35-49 years (unweighted n = 1,681). Using data from the Third National Health and Nutrition Examination Survey (1988-1994), we conducted Poisson regression to estimate adjusted relative risks and 95% confidence intervals. Because the best approach to correcting for urinary dilution in spot samples with creatinine remains controversial, we employed 3 approaches: standardization, covariate adjustment, and covariate-adjusted standardization. Our data suggested a modest association with standardization (highest quartile vs. lowest: relative risk (RR) = 1.3, 95% confidence interval (CI): 0.8, 1.9; P for trend = 0.06) and covariate-adjusted standardization (highest quartile vs. lowest: RR = 1.3, 95% CI: 0.9, 1.9; P for trend = 0.05) and a stronger association with covariate adjustment (highest quartile vs. lowest: RR = 1.8, 95% CI: 1.2, 2.9; P for trend = 0.01). The stronger association with covariate adjustment may reflect bias from conditioning on urinary creatinine, a collider in the hypothesized causal pathway. We conclude that cadmium may contribute to ovarian aging in women and that careful consideration of the creatinine adjustment approach is needed to minimize bias.

Vaginal pH as a Diagnostic Tool for Menopause: A Preliminary Analysis

Introduction

Menopause is defined as the permanent cessation of menstruation, as a result of decrease in ovarian follicles and the loss of ovarian activity. There is decrease in inhibin B level which causes decrease in negative feedback on the serum follicle-stimulating hormone (FSH), which in turn increases the level of serum FSH. Serum FSH is routinely used as a marker of menopause. Decline in the estrogen level causes thinning of vaginal epithelium, resulting in less exfoliation of the vaginal epithelial cells, lesser available glycogen, and decreased substrate for acid production, leading to increase in vaginal pH.

Aims

The aim of this study is to compare the sensitivity of vaginal pH versus serum FSH level to diagnose menopause.

Settings and Design

This is a cross-sectional study, performed in obstetrics and gynecology outpatient department of a teaching hospital of central Gujarat.

Subjects and Methods

A total of 120 women who had their last menstrual period >1 year back (menopause) were included in the study. Vaginal pH was measured and serum sample was taken to measure FSH level. Sensitivity of both vaginal pH and serum FSH to diagnose menopause was compared. McNemar test was used to analyze the convergence of the two methods for the diagnosis of menopause.

Results

In the absence of vaginal infection, sensitivity of vaginal pH to diagnose menopause was 90%, while sensitivity of the serum FSH was 85%.

Conclusions

Sensitivity of the vaginal pH is similar to the serum FSH for diagnosis of menopause.

The Diagnostic Utility of the Basal Luteinizing Hormone Level and Single 60-Minute Post GnRH Agonist Stimulation Test for Idiopathic Central Precocious Puberty in Girls

OBJECTIVE

The present study aimed to assess the diagnostic utility of the Luteinizing hormone (LH) levels and single 60-minute post gonadotropin-releasing hormone (GnRH) agonist stimulation test for idiopathic central precocious puberty (CPP) in girls.

METHODS

Data from 1,492 girls diagnosed with precocious puberty who underwent GnRH agonist stimulation testing between January 1, 2016, and October 8, 2020, were retrospectively reviewed. LH levels and LH/follicle-stimulating hormone (FSH) ratios were measured by immuno-chemiluminescence assay before and at several timepoints after GnRH analogue stimulation testing. Mann-Whitney U test, Spearman's correlation, χ² test, and receiver operating characteristic (ROC) analyses were performed to determine the diagnostic utility of these hormone levels.

RESULTS

The 1,492 subjects were split into two groups: an idiopathic CPP group (n = 518) and a non-CPP group (n = 974). Basal LH levels and LH/FSH ratios were significantly different between the two groups at 30, 60, 90, and 120 minutes after GnRH analogue stimulation testing. Spearman's correlation analysis showed the strongest correlation between peak LH and LH levels at 60 minutes after GnRH agonist stimulation (r = 0.986, P < 0.001). ROC curve analysis revealed that the 60-minute LH/FSH ratio yielded the highest consistency, with an area under the ROC curve (AUC) of 0.988 (95% confidence interval [CI], 0.982-0.993) and a cut-off point of 0.603 mIU/L (sensitivity 97.3%, specificity 93.0%). The cut-off points of basal LH and LH/FSH were 0.255 mIU/L (sensitivity 68.9%, specificity 86.0%) and 0.07 (sensitivity 73.2%, specificity 89.5%), respectively, with AUCs of 0.823 (95% CI, 0.799-0.847) and 0.843 (95% CI, 0.819-0.867), respectively.

CONCLUSIONS

A basal LH value greater than 0.535 mIU/L can be used to diagnose CPP without a GnRH agonist stimulation test. A single 60-minute post-stimulus gonadotropin result of LH and LH/FSH can be used instead of a GnRH agonist stimulation test, or samples can be taken only at 0, 30, and 60 minutes after a GnRH agonist stimulation test. This reduces the number of blood draws required compared with the traditional stimulation test, while still achieving a high level of diagnostic accuracy.