Effect Of Follicle-stimulating Hormone Research Articles

FSH induces apoptosis in follicular granulosa cells of Tianzhu white yak and regulates the expression of Fas/FasL mRNA.

The Tianzhu white yak, a globally rare species, holds immense value as a source for yak materials. While the Fas/FasL pathway is pivotal in granulosa cells apoptosis, its precise molecular workings remain enigmatic. This study endeavours to decipher the role of follicle-stimulating hormone (FSH) in suppressing ovarian granulosa cells (GC) apoptosis in the Tianzhu white yak. Utilizing advanced cell culture techniques, we employed the MTT method, flow cytometry, fluorescence labelling and RT-PCR to investigate the apoptotic effects of FSH on yak GCs. Our results reveal that FSH's inhibitory effect on GC apoptosis follows a normal distribution pattern, peaking at an FSH concentration of 100 ng/mL with an apoptosis inhibition rate of 89.31%. When serum was withdrawn, an FSH concentration of 2 × 106 ng/mL reduced apoptosis by 72.84%. Annexin V-FITC staining revealed membrane invaginations, bubble and protrusion formation on the cell surface, and alterations in membrane structure and cell morphology. Flow cytometry analysis further demonstrated that FSH administration prior to early granulosa cell apoptosis had a more profound effect than during gradual apoptosis, both showing a suppressive effect on early follicular granulosa cell apoptosis. A transcription-level analysis conducted 3 h prior to serum withdrawal, with the addition of 100 ng/mL FSH, revealed intricate regulations in the expression of Fas/FasL. Notably, we observed a gradual increase in FasL expression over time, yet the presence of FSH effectively down-regulated FasL expression to baseline levels, without notable changes in Fas expression. Immunocytochemical analysis further confirmed the presence of both Fas and FasL on the cell membrane, nucleus and cytoplasm, with varying intensities depending on the duration of FSH treatment. Our findings suggest that FSH may suppress the apoptotic pathway in follicular primarily by down-regulating FasL expression, indicating that Fas-regulated mitochondrial pathways play a more prominent role compared to death receptor pathways. This study offers a fresh perspective on the mechanism underlying follicular atresia in Tianzhu white yaks and lays a solid theoretical foundation for the expansion of this endangered species' population.

P-695 Optimizing oocyte donor stimulation: A revelation from 2,666 cases emphasizing the sole efficacy of exogenous FSH

Abstract Study question Does the administration of human menopausal gonadotrophin in controlled ovarian stimulation improve clinical outcomes in the oocyte donation program? Summary answer The addition of hMG (human menopausal gonadotropin) reduces the number of retrieved oocytes without improving embryo development or clinical outcomes in oocyte donation program. What is known already In controlled ovarian stimulation for assisted reproduction treatments, follicle stimulating hormone(FSH) is essential, but the importance of LH supplementation from menopausal origin is controversial. It is a common practice to use hMG to provide the LH effect. The standard preparation contains FSH and LH effects in a 1:1 ratio.The FSH component would recruit ovarian follicles and stimulate their growth, while the LH component would facilitate their maturation. Our aim was to compare the outcomes of intracytoplasmic sperm injection (ICSI) treatments using a gonadotropin-releasing hormone GnRH) antagonist protocol with recombinant FSH(FSHr) alone and supplemented with hMG in the oocyte donation program. Study design, size, duration This is a retrospective cohort study of 2,666 patients enrolled in the oocyte donation program at a single center over four consecutive years. Donor stimulation commenced with daily FSHr injections. The FSHr group (n = 2,078) continued FSHr, while the FSHr+hMG group (n = 588) received hMG. Participants/materials, setting, methods Donors received GnRH agonist via i.m. injection until a mean diameter >18 mm in at least eight follicles. Transvaginal oocyte retrieval was scheduled 36h later, followed by ICSI for all retrieved oocytes. Embryos were cultured in time-lapse systems and evaluated using an artificial intelligence-based model (iDAScore v2). Recipients underwent hormone replacement therapy for endometrial preparation. Our comparative study examined oocytes retrieved, embryo score, implantation, and live birth outcomes in fresh and frozen embryo transfers (ETs). Main results and the role of chance The number of retrieved oocytes was higher in the FSHr group than in the FSHr+hMG group: 24.9±10.6 vs. 18.2±8.8 (p < 0.001). In addition, embryos from the FSHr+hMG group exhibited slower early development, with significantly lower division times to two, three, four and five cells in the FSHr group (p < 0.005). However, late parameters of embryo development showed no differences. Automatic scoring by the deep learning algorithm was identical for blastocysts in the FSHr (4.8±2.8) and FSHr+hMG groups (4.8±2.8); p = 1. Implantation rates showed no significant differences for fresh ET (FSHr: 58.6% vs. FSHr+hMG: 61.9%; n = 2,073; p = 1) or frozen ET (FSHr: 49.3% vs. FSHr+hMG: 46%; n = 2,687; p = 1). Similarly, there were no differences in live birth rates for fresh ET (FSHr: 45.6% vs. FSHr+hMG: 50.3%; n = 1,993; p = 1) or frozen ET (FSHr: 31.8% vs. FSHr+hMG: 33.8%; n = 2,508; p = 1). Limitations, reasons for caution The retrospective and single-center nature of the study would be its main limitations. It is essential to emphasize that these results are only applicable within the oocyte donation program. Wider implications of the findings Based on our findings, the use of exogenous FSHr alone is likely adequate in the GnRH antagonist protocol for optimal ovarian stimulation of donors, leading to the production of high-quality embryos and successful clinical outcomes. Trial registration number Not Applicable

A Dose-Response Study on Functional and Transcriptomic Effects of FSH on Ex Vivo Mouse Folliculogenesis.

Follicle-stimulating hormone (FSH) binds to its membrane receptor (FSHR) in granulosa cells to activate various signal transduction pathways and drive the gonadotropin-dependent phase of folliculogenesis. Both FSH insufficiency (due to genetic or nongenetic factors) and FSH excess (as encountered with ovarian stimulation in assisted reproductive technology [ART]) can cause poor female reproductive outcomes, but the underlying molecular mechanisms remain elusive. Herein, we conducted single-follicle and single-oocyte RNA sequencing analysis along with other approaches in an ex vivo mouse folliculogenesis and oogenesis system to investigate the effects of different concentrations of FSH on key follicular events. Our study revealed that a minimum FSH threshold is required for follicle maturation into the high estradiol-secreting preovulatory stage, and such threshold is moderately variable among individual follicles between 5 and 10 mIU/mL. FSH at 5, 10, 20, and 30 mIU/mL induced distinct expression patterns of follicle maturation-related genes, follicular transcriptomics, and follicular cAMP levels. RNA sequencing analysis identified FSH-stimulated activation of G proteins and downstream canonical and novel signaling pathways that may critically regulate follicle maturation, including the cAMP/PKA/CREB, PI3K/AKT/FOXO1, and glycolysis pathways. High FSH at 20 and 30 mIU/mL resulted in noncanonical FSH responses, including premature luteinization, high production of androgen and proinflammatory factors, and reduced expression of energy metabolism-related genes in oocytes. Together, this study improves our understanding of gonadotropin-dependent folliculogenesis and provides crucial insights into how high doses of FSH used in ART may impact follicular health, oocyte quality, pregnancy outcome, and systemic health.

FSH, bone, belly and brain.

The pituitary gland orchestrates multiple endocrine organs by secreting tropic hormones, and therefore plays a significant role in a myriad of physiological processes, including skeletal modeling and remodeling, fat and glucose metabolism, and cognition. Expression of receptors for each pituitary hormone and the hormone itself in the skeleton, fat, immune cells, and the brain suggest that their role is much broader than the traditionally attributed functions. FSH, believed solely to regulate gonadal function is also involved in fat and bone metabolism, as well as in cognition. Our emerging understanding of nonreproductive functions of FSH, thus, opens potential therapeutic opportunities to address detrimental health consequences during and after menopause, namely, osteoporosis, obesity, and dementia. In this review, we outline current understanding of the cross-talk between the pituitary, bone, adipose tissue, and brain through FSH. Preclinical evidence from genetic and pharmacologic interventions in rodent models, and human data from population-based observations, genetic studies, and a small number of interventional studies provide compelling evidence for independent functions of FSH in bone loss, fat gain, and congnitive impairment.

Effects of follicle-stimulating hormone on energy balance and tissue metabolic health after loss of ovarian function.

Loss of ovarian function imparts increased susceptibility to obesity and metabolic disease. These effects are largely attributed to decreased estradiol (E2), but the role of increased follicle-stimulating hormone (FSH) in modulating energy balance has not been fully investigated. Previous work that blocked FSH binding to its receptor in mice suggested this hormone may play a part in modulating body weight and energy expenditure after ovariectomy (OVX). We used an alternate approach to isolate the individual and combined contributions of FSH and E2 in mediating energy imbalance and changes in tissue-level metabolic health. Female Wistar rats were ovariectomized and given the gonadotropin releasing hormone (GnRH) antagonist degarelix to suppress FSH production. E2 and FSH were then added back individually and in combination for a period of 3 wk. Energy balance, body mass composition, and transcriptomic profiles of individual tissues were obtained. In contrast to previous studies, suppression and replacement of FSH in our paradigm had no effect on body weight, body composition, food intake, or energy expenditure. We did, however, observe organ-specific effects of FSH that produced unique transcriptomic signatures of FSH in retroperitoneal white adipose tissue. These included reductions in biological processes related to lipogenesis and carbohydrate transport. In addition, rats administered FSH had reduced liver triglyceride concentration (P < 0.001), which correlated with FSH-induced changes at the transcriptomic level. Although not appearing to modulate energy balance after loss of ovarian function in rats, FSH may still impart tissue-specific effects in the liver and white adipose tissue that might affect the metabolic health of those organs.NEW & NOTEWORTHY We find no effect of follicle-stimulating hormone (FSH) on energy balance using a novel model in which rats are ovariectomized, subjected to gonadotropin-releasing hormone antagonism, and systematically given back FSH by osmotic pump. However, tissue-specific effects of FSH on adipose tissue and liver were observed in this study. These include unique transcriptomic signatures induced by the hormone and a stark reduction in hepatic triglyceride accumulation.

Follicle-stimulating hormone accelerates osteoclast migration by enhancing methyltransferase-like 3-mediated m6A methylation of cathepsin K.

Follicle-stimulating hormone (FSH) accelerates osteoporosis in postmenopausal women, while the underlying mechanism remains uncharacterized. N6-methyladenosine (m6A) is one of the most important regulations in the development of osteoporosis. In this study, we aimed to investigate the role of FSH in m6A modification and osteoclast function. Here, we showed that FSH upregulated m6A levels in osteoclasts via stimulating methyltransferase-like 3 (METTL3) protein expression. FSH enhanced osteoclast migration, while the knockdown of METTL3 eliminated this enhancement. Both MeRIP-seq and RNA sequencing identified that cathepsin K (CTSK) is the potential downstream target of METTL3. Knockdown of CTSK reduced FSH-upregulated osteoclast migration. Furthermore, silencing METTL3 decreased CTSK mRNA stability. Finally, FSH induced phosphorylation of cyclic-AMP response element-binding protein (CREB), while silencing of CREB attenuated the effects of FSH on the promoter transcriptional activity of Mettl3 and CTSK/METTL3 protein. Taken together, these findings indicate that FSH promotes osteoclast migration via the CREB/METTL3/CTSK signaling pathway, which may provide a potential target for suppressing osteoclast mobility and postmenopausal osteoporosis therapy.

FSH Is Responsible for Androgen Deprivation Therapy-Associated Atherosclerosis in Mice by Exaggerating Endothelial Inflammation and Monocyte Adhesion.

Androgen deprivation therapy (ADT) is the mainstay treatment for advanced prostate cancer. But ADTs with orchiectomy and gonadotropin-releasing hormone (GnRH) agonist are associated with increased risk of cardiovascular diseases, which appears less significant with GnRH antagonist. The difference of follicle-stimulating hormone (FSH) in ADT modalities is hypothesized to be responsible for ADT-associated cardiovascular diseases. We administered orchiectomy, GnRH agonist, or GnRH antagonist in male ApoE-/- mice fed with Western diet and manipulated FSH levels by testosterone and FSH supplementation or FSH antibody to investigate the role of FSH elevation on atherosclerosis. By combining lipidomics, in vitro study, and intraluminal FSHR (FSH receptor) inhibition, we delineated the effects of FSH on endothelium and monocytes and the underlying mechanisms. Orchiectomy and GnRH agonist, but not GnRH antagonist, induced long- or short-term FSH elevation and significantly accelerated atherogenesis. In orchiectomized and testosterone-supplemented mice, FSH exposure increased atherosclerosis. In GnRH agonist-treated mice, blocking of short FSH surge by anti-FSHβ antibody greatly alleviated endothelial inflammation and delayed atherogenesis. In GnRH antagonist-treated mice, FSH supplementation aggravated atherogenesis. Mechanistically, FSH, synergizing with TNF-α (tumor necrosis factor alpha), exacerbated endothelial inflammation by elevating VCAM-1 (vascular cell adhesion protein 1) expression through the cAMP/PKA (protein kinase A)/CREB (cAMP response element-binding protein)/c-Jun and PI3K (phosphatidylinositol 3 kinase)/AKT (protein kinase B)/GSK-3β (glycogen synthase kinase 3 beta)/GATA-6 (GATA-binding protein 6) pathways. In monocytes, FSH upregulated CD29 (cluster of differentiation 29) expression via the PI3K/AKT/GSK-3β/SP1 (specificity protein 1) pathway and promoted monocyte-endothelial adhesion both in vitro and in vivo. Importantly, FSHR knockdown by shRNA in endothelium of carotid arteries markedly reduced GnRH agonist-induced endothelial inflammation and atherosclerosis in mice. FSH is responsible for ADT-associated atherosclerosis by exaggerating endothelial inflammation and promoting monocyte-endothelial adhesion.

The follicle-stimulating hormone triggers rapid changes in mitochondrial structure and function in porcine cumulus cells

Oocyte maturation is a key process during which the female germ cell undergoes resumption of meiosis and completes its preparation for embryonic development including cytoplasmic and epigenetic maturation. The cumulus cells directly surrounding the oocyte are involved in this process by transferring essential metabolites, such as pyruvate, to the oocyte. This process is controlled by cyclic adenosine monophosphate (cAMP)-dependent mechanisms recruited downstream of follicle-stimulating hormone (FSH) signaling in cumulus cells. As mitochondria have a critical but poorly understood contribution to this process, we defined the effects of FSH and high cAMP concentrations on mitochondrial dynamics and function in porcine cumulus cells. During in vitro maturation (IVM) of cumulus-oocyte complexes (COCs), we observed an FSH-dependent mitochondrial elongation shortly after stimulation that led to mitochondrial fragmentation 24 h later. Importantly, mitochondrial elongation was accompanied by decreased mitochondrial activity and a switch to glycolysis. During a pre-IVM culture step increasing intracellular cAMP, mitochondrial fragmentation was prevented. Altogether, the results demonstrate that FSH triggers rapid changes in mitochondrial structure and function in COCs involving cAMP.

Is FSH combined with equine chorionic gonadotropin able to modify lipid metabolism in bovine superstimulated antral follicles?

Lipid metabolism is essential for ensuring oocyte maturation and embryo development. β-Oxidized fatty acids (FA) are a potent source of energy for cells, particularly for bovine somatic follicular cells. Superstimulatory protocols using follicle stimulating hormone (FSH) or FSH combined with equine chorionic gonadotropin (eCG) are capable of stimulating the follicular microenvironment and drive the expression of biomarker genes associated with lipid metabolism in the cumulus-oocyte complex (COC) for better embryo development. In this study, we assesed the effects of FSH and FSH/eCG protocols on the expression of genes related to lipid metabolism in bovine granulosa cells (GCs). Further, we measured triglyceride levels in follicular fluid (FF) obtained from both superstimulatd and non-superstimulated cows (synchronized cows). In summary, superstimulation with gonadotropins maintained the TG levels in bovine FF and ensured GCs mRNA abundance of ACSL1, ACSL3, ACSL6, SCD, ELOVL5, ELOVL6, FASN, FADS2, and SREBP1. We, however, found the abundance of CPTIB mRNA to be lower in GCs obtained from cows subjected to FSH/eCG protocols than synchronized cows. In conclusion, the findings of this study showed that ovarian superstimulation around the preovulatory phase has a mild impact on the lipid metabolism in GCs.

Effect of follicle-stimulating hormone and luteinizing hormone on apoptosis, autophagy, and the release and reception of some steroid hormones in yak granulosa cells through miR-23a/ASK1 axis

Follicle-stimulating hormone (FSH), luteinizing hormone (LH), miR-23a, apoptosis signal-regulating kinase 1(ASK1)/c-Jun N-terminal kinase (JNK), autophagy and apoptosis play crucial roles in follicular development. However, their role in yak granulosa cells (GCs) remains unknown. Therefore, we examined the effect of miR-23a, ASK1, FSH, and LH on apoptosis, autophagy, and the release and reception of some steroid hormones in these cells. Our results showed that miR-23a overexpression significantly increased the abundance of Beclin1, the LC3II/I ratio, and the number of Ad-mRFP-GFP-LC3-labeled autophagosomes, and decreased p62 abundance. Additionally, Bax abundance and the number of terminal deoxynucleotidyl transferase deoxynucleotide triphosphate nick end labeling-positive cells were reduced, while Bcl2 expression was increased. Overexpression of miR-23a also significantly increased the abundance of estradiol receptor α (ER-α) and β (ER-β) and the concentrations of estradiol (E2), progesterone (P4) in yak GCs. Here, treating yak GCs with miR-23a decreased ASK1 expression, which regulates ASK1/JNK-mediated apoptosis, autophagy, E2 and P4 levels, and ER-α/β abundance. In contrast, treatment of yak GCs with FSH (10 μg/mL) and LH (100 μg/mL) increased miR-23a abundance, regulating the subsequent effect on ASK1/JNK-mediated apoptosis, autophagy, ER-α/β abundance, and E2 and P4 concentrations. In conclusion, miR-23a enhances autophagy in yak GCs, attenuates apoptosis, and increases ER-α/β abundance and E2 and P4 concentrations by downregulating ASK1. Additionally, FSH and LH can regulate these effects of miR-23a by altering its expression. These results provide important insights that can inform the development of strategies to reduce abnormal follicular atresia and improve the reproductive rate of yaks.

FSH preserves the viability of hypoxic granulosa cells viaactivating the HIF-1α-GAS6-Axl-Akt pathway.

The developmental fate of ovarian follicles is primarily determined by the survival status (proliferation or apoptosis) of granulosa cells (GCs). Owing to the avascular environment within follicles, GCs are believed to live in a hypoxic niche. Follicle-stimulating hormone (FSH) has been reported to improve GCs survival by governing hypoxia-inducible factor-1α (HIF-1α)-dependent hypoxia response, but the underlying mechanisms remain poorly understood. Growth arrest-specific gene 6 (GAS6) is a secreted ligand of tyrosine kinase receptors, and has been documented to facilitate tumor growth. Here, we showed that the level of GAS6 was markedly increased in mouse ovarian GCs after the injection of FSH. Specifically, FSH-induced GAS6 expression was accompanied by HIF-1α accumulation under conditions of hypoxia both in vivo and in vitro, whereas inhibition of HIF-1αwith smallinterfering RNAs/antagonist repressed both expression and secretion of GAS6. As such, Luciferase reporter assay and chromatin immunoprecipitation assay showed that HIF-1α directly bound to a hypoxia response element site within the Gas6 promoter and contributed to the regulation of GAS6 expression in response to FSH. Notably, blockage of GAS6 and/or its receptor Axl abrogated the pro-survival effects of FSH under hypoxia. Moreover, phosphorylation of Axl by GAS6 is required for FSH-mediated Akt activation and the resultant pro-survival phenotypes. Finally, the in vitro findings were verified in vivo, which showed that FSH-induced proliferative and antiapoptotic effects in ovarian GCs were diminished after blocking GAS6/Axl using HIF-1α antagonist. These findings highlight a novel function of FSH in preserving GCs viability against hypoxic stress by activating the HIF-1a-GAS6-Axl-Akt pathway.

Effects of Calcium, Available Phosphorus and Microbial Phytase on Ovarian FSHR and LHR Expression in Laying Hens

Folliculogenesis, steroidogenesis, ovulation, and vitellogenesis are regulated by the effect of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in the hypothalamus-pituitary-ovary axis and these hormones act via follicle stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) in the ovary. Poultry ration and food additives are essential in the regulation of reproductive activity. Phytase is a supplement frequently added to laying hen diets to increase phosphorus (P) utilization. The aim of this study was to reveal the effects of a newly isolated microbial phytase together with different concentrations of calcium (Ca2+) and available phosphorus (AP) on ovarian FSHR and LHR expressions. For this purpose, 90 Lohmann LSL-White layers were first divided into three main diet groups (standard Ca2+ and AP, standard Ca2+ and low AP, low Ca2+ and AP) and then into three subgroups (no-phytase, commercial phytase, and microbial phytase). At the end of the experiment, all chickens were slaughtered and ovarian tissues were fixed in formalin. Routine avidin-biotin complex immunohistochemistry was performed using anti-FSHR and anti-LHR primary antibodies. Immunohistochemically, FSHR and LHR were expressed in granulosa/theca cells, oocytes, interstitial cells, and vitellus. While the expression intensity of the receptors increased in the microbial phytase-treated groups, the strongest expression was obtained in the granulosa/theca cells and oocytes in the standard Ca and low AP group. In conclusion, we suggest that the addition of newly isolated microbial phytase to diets of laying hens and feeding standard Ca and low AP may have positive effects on reproductive performance by increasing the FSHR and LHR expression in ovaries.

Sphingosine-1-phosphate mediates FSH-induced cell viability but not steroidogenesis in bovine granulosa cells

Follicle-stimulating hormone (FSH) stimulates the proliferation, survival, and estradiol synthesis of granulosa cells by binding to their G protein-coupled receptors. Although FSH activates sphingosine kinase-1 (SPHK1) to induce sphingosine-1-phosphate (S1P) synthesis, which is required to mediate the proliferative and survival effect of this gonadotrophin, the mechanisms, and the role of S1P in estradiol synthesis have not been reported. This study aimed to evaluate the importance of FSH-induced S1P synthesis as a mediator of the effects of this gonadotrophin on granulosa cell viability and steroidogenesis and to determine if FSH-induced S1P synthesis depends on estradiol, cAMP, PKA, or PKC. To achieve these objectives, we tested the effects of FSH, a sphingosine kinase-1 inhibitor (SKI-178), estradiol and inhibitors of aromatase, cAMP, PKA, and PKC (Formestane, MDL-12330A, H-89 dihydrochloride hydrate and Calphostin C respectively), on granulosa cell viability, S1P and estradiol production, and the mRNA expression of CYP19A1 and STAR in four in vitro culture experiments. The addition of FSH (1 ng/mL) increased (P < 0.05) granulosa cells number and S1P concentration in the culture media. Conversely, the addition of SKI-178 (10 μM) reduced (P < 0.05) S1P concentration negating the effect of FSH on cell viability. Inhibition of PKC and PKA, but not cAMP, reduced (P < 0.05) S1P secretion of FSH treated granulosa cells. It is important to note that the reduction in S1P secretion was strong (49 %) with the use of the PKC inhibitor. The use of formestane (10 μg) did not modify (P > 0.05) S1P secretion in FSH-treated cells; however, the addition of 5 or 10 ng/mL of estradiol increased (P < 0.05) S1P secretion. Finally, FSH increased (P < 0.05) estradiol concentration in the culture media, but this effect was not blocked by the inhibition of S1P synthesis. Similarly, FSH, SKI-178 or their combination did not modify the mRNA expression of CYP19A1 and STAR. In conclusion, S1P synthesis is stimulated FSH in granulosa cells and mediated mainly by PKC. S1P in turn promotes the granulosa cell viability, however, this does not influence estradiol synthesis. Additionally, estradiol synthesis induced by FSH is not essential for S1P synthesis, however high estradiol concentration may stimulate S1P production by granulosa cells.

FRI675 Higher FSH Level Is Associated With Increased Risk Of Incident Hip Fracture In Older Adults, Independent Of Sex Hormone Levels

Abstract Disclosure: E.H. Koh: None. S.K. Ewing: None. S. Sigurdsson: None. V. Guðnason: None. T.F. Hue: None. E. Vittinghoff: None. M. Zaidi: Research Investigator; Self; patents on FSH, bone, body fat and neurodegeneration. Held by Icahn School of Medicine and Mount Sinai. C.J. Rosen: None. C. Ohlsson: None. L. Grahnemo: None. Å. Tivesten: None. A.V. Schwartz: None. A.L. Schafer: None. Higher levels of follicle stimulating hormone (FSH) are associated with bone loss among women during the perimenopausal transition and among older men, independent of sex hormone levels. In vitro studies have shown bone remodeling via FSH-receptors on bone cells. Furthermore, treating ovariectomized mice with FSH-blocking polyclonal antibodies results in increased bone mineral density. However, it is uncertain whether this association of FSH elevation and bone loss translates to increased fracture risk. To examine the relationship between FSH and incident hip fracture, independent of sex hormone levels, we used a case-cohort design to sample from the AGES-Reykjavik cohort, a longitudinal cohort of 5764 older Icelandic adults designed to assess gene/environment interactions and their relationship to diseases in old age. Baseline visits took place from 2002 and through 2006. We excluded those with prior hip fracture, those whose quantitative computed tomography bone mineral density scan quality was unacceptable, or who were taking sex hormone replacement, sex hormone antagonists, or glucocorticoid medications. We randomly sampled, stratified by sex, 147 women and 148 men to form our subcohort. Our cases were comprised of a random sample, stratified by sex, of 133 women and 122 men (of whom 25 were in the subcohort) who sustained incident hip fracture within 10 years of the baseline visit. Fractures were adjudicated and recorded in the AGES-Reykjavik fracture registry. FSH and sex hormone binding globulin (SHBG) were measured on baseline serum by immunoassay and estradiol and total testosterone by mass spectrometry. Robust weighted Cox proportional hazards models were used to determine the relationship between FSH and subsequent risk of hip fracture, with adjustment for covariates. Among the subcohort, mean age was 76 years. In women, mean ± SD FSH was 64.4 ± 25.5 IU/L with estradiol 5.7 ± 4.2 pg/mL, testosterone 22.5 ± 10.4 ng/dL, and SHBG 74.0 ± 33.8 nmol/L. In men, mean FSH was 12.2 ± 11.9 IU/L with estradiol 21.3 ± 6.9 pg/mL, testosterone 457.9 ± 171.2 ng/dL, and SHBG 52.8 ± 17.5 nmol/L. No interaction was identified between FSH and sex for the relationship with fracture, so men and women were pooled for analysis. Higher levels of FSH were associated with a significant increased risk of incident hip fracture in models adjusted for age and sex [hazard ratio (HR) 1.24 (95% CI 1.04-1.48, p=0.02)] and after further adjustment for estradiol, testosterone, and SHBG levels [HR 1.20 (95% 1.01-1.44, p=0.04)] per sex-specific SD increase in FSH level. Our findings support a growing body of evidence for direct pleiotropic effects of FSH on bone. FSH may contribute to aging and disability independent of sex hormone levels. Presentation: Friday, June 16, 2023

SAT667 Follicle-Stimulating Hormone Does Not Directly Regulate Adipogenesis Via The FSH Receptor In Mice

Abstract Disclosure: M. Loka: None. L. Ongaro Gambino: None. T. Uliasz: None. L.A. Jaffe: None. L. Kazak: None. D.J. Bernard: None. Rising rates of obesity are a serious public health challenge. Post-menopausal women are at higher risk of developing obesity and associated comorbidities than premenopausal women, with hormonal changes, such as reduced estrogens, likely to be contributing factors. Menopause is also characterized by increases in pituitary-derived follicle-stimulating hormone (FSH). Recent data suggest that FSH may directly stimulate adipogenesis and block thermogenesis in adipocytes. FSH reportedly decreased expression of thermogenic genes (Cox8b and Ucp1) in murine 3T3-L1 cells differentiated into adipocytes. FSH’s inhibitory effects were no longer apparent in the presence of an FSH-neutralizing antibody. The same FSH antibody reduced fat mass and increased lean mass in ovariectomized (OVX) female mice, a rodent model of menopause. In these studies, it was not established whether FSH acted directly through its canonical receptor (FSHR) in adipocytes to mediate its effects. To address this gap, we differentiated 3T3-L1 cells to adipocytes and treated with FSH. In contrast to the earlier report, FSH did not alter the expression of markers of lipogenesis (Cebpa and Pparg2) or thermogenesis (Cox8b and Ucp1) nor did it impact mitochondrial respiration or lipid accumulation. We also did not detect Fshr mRNA in these cells. We next differentiated the stromal vascular fraction from inguinal adipose tissue of adult male mice into white adipocytes. After 10 days of differentiation, FSH treatment did not alter expression of several markers of adipogenesis and did not affect lipid accumulation. To assess FSH actions in vivo, we generated adipocyte-specific Fshr knockout mice (Fshrfx/fx;Adipoq-Cre, hereafter cKO). Ten-week-old cKO and control female mice were OVX and maintained on standard chow. Eight to 10 weeks later, we performed glucose tolerance and insulin tolerance tests, and determined body composition by EchoMRI. Cre-mediated recombination of the floxed Fshr locus in adipocytes was successful, but did not alter body weight, fat or lean mass, or glucose metabolism in cKO relative to control OVX mice. Furthermore, using a newly developed FSHR-3xHA knockin mouse model, we detected FSHR protein expression in ovary, but not in inguinal and perigonadal white adipose depots or in intrascapular brown adipose tissue. We similarly failed to detect Fshr mRNA in various fat depots in control mice. Collectively, our results fail to show FSH effects on adipogenesis in vitro and challenge the hypothesis that FSH acts through the classical FSHR in adipocytes in vivo. Presentation: Saturday, June 17, 2023

Effects of follicle-stimulating hormone on the proliferation and apoptosis of infantile hemangioma stem cells

ObjectiveTo investigate the effects of different concentrations of follicle-stimulating hormone (FSH) on the proliferation and apoptosis of human hemangioma stem cells, it will provide a basis for studying the mechanism of FSH in treating hemangioma. MethodsHemangioma specimens were collected from the Longgang District Maternity & Child Healthcare Hospital of Shenzhen City. Hemangioma stem cells were treated with different concentrations of FSH. Cell viability was detected by CCK8 method and cell apoptosis was analyzed by flow cytometry. ResultsHemangioma stem cells (HemSCs) were extracted from fresh tissue of infantile hemangioma by the CD133 immunomagnetic bead method. Under the influence of FSH at different concentrations (0, 100, 1000 IU/L), the cell viability of hemangioma stem cells increased significantly in a concentration-dependent manner (P < 0.05). At the same time, the apoptosis of hemangioma stem cells decreased with increasing concentrations of follicle-stimulating hormone (P < 0.05). Specifically, 1000 IU/L FSH significantly promoted the proliferation of hemangioma stem cells and inhibited their apoptosis. ConclusionHigh concentration of follicle-stimulating hormone can maintain the growth of hemangioma by promoting the proliferation and inhibiting the apoptosis of hemangioma stem cells.

Elevated circulating follicle stimulating hormone level is associated with dyslipidemia in male type 2 diabetes mellitus patients: A cross-sectional study.

Type 2 diabetes mellitus (T2DM) commonly combines with dyslipidemia, and both are known as the risk factors of cardiovascular events and aggravate the arteriosclerosis progression. In this study, we investigated the relationship between follicle-stimulating hormone (FSH) and lipid profiles in male T2DM patients. We collected clinical data of male T2DM patients in the Chinese Han population hospitalised from January 2018 to June 2020. A total of 963 patients with a mean age of 58.89±12.25years old were enroled in this study. The results showed that the levels of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL)-C levels were decreased gradually from the highest quartile groups (Q4) to Q1 group relevant to luteinising hormone and FSH, and no significant difference was observed in high-density lipoprotein-C levels among Q4-Q1 groups. Sub-groups analysis showed that, with the increased FSH level, TC, TG, and LDL-C levels were increased in the elder group (40-59years old) than those in the younger group (20-39years old). Spearman's analysis revealed a positive correlation between FSH and the levels of TC, TG, and LDL-C (r=0.354, r=0.336, r=0.312, p<0.001, respectively). The effect of FSH is independent of the changes in total testosterone level. Multivariate analysis found that increased FSH levels (≥9.26mIU/mL) and decreased total testosterone levels (<13.30nmol/L) were positively correlated with high TC, TG, and LDL-Cemia (OR=4.014, 1.565, 1.602, 1.660, 2.127, 1.322, respectively, p<0.05). Our data suggest that high serum FSH level in male T2DM patients could be a potential independent risk factor correlated with the elevated TC, TG, and LDL-C.

Effect of insulin resistance on gonadotropin and bone mineral density in nondiabetic postmenopausal women.

The effects of insulin resistance (IR) on bone mineral density (BMD) are unclear. This investigation aimed to assess the impact of IR and hyperinsulinemia on bone health. Determine whether IR mediates the link between follicle-stimulating hormone (FSH) and bone mass in nondiabetic postmenopausal women. Retrospective cross-sectional study. Health checkup center of Hangzhou Women's Hospital. This study comprised 437 nondiabetic postmenopausal women. BMD was evaluated using dual-energy X-rays. Fasting sera were analyzed for insulin and glucose levels, and indicators related to IR were determined. By pathway analysis, we examined the indirect effects of FSH on BMD via the mediators Homeostatic Model Assessment for insulin resistance (HOMA-IR) and fasting insulin (FINS) after correction for confounding factors. After adjusting for age and body mass index (BMI) in linear regression, HOMA-IR and FINS were linked with FSH (P<0.05). IR was stronger among women in the normal BMD group than those in the osteoporosis or osteopenia group. In unadjusted models, BMD was greater in those with higher HOMA-IR and FINS (β=0.027, P=0.006 and β=0.033, P=0.003, respectively). After correcting for BMI and other possible variables, these associations remained. In addition, path models for FSH demonstrated a negative association with BMD by HOMA-IR (95% confidence interval [CI]: -0.0174 to -0.0014) and FINS (95% CI: -0.0188 to -0.002). Greater IR was associated with increased BMD in nondiabetic postmenopausal women, regardless of BMI and other variables. HOMA-IR or FINS could play a novel mediating role in FSH-induced BMD suppression.

Exploring Independent Effects of Follicle-Stimulating Hormone In Vivo in a Mouse Model.

During the transition from a reproductive to a nonreproductive phase (menopause), many women experience significant physiological and pathological changes, including decreased bone mass, increased blood lipids, and increased visceral adiposity. Levels of follicle-stimulating hormone (FSH) rise during the menopausal transition. Many studies have shown that FSH in various extragonadal tissues and organs is associated with the pathogenesis of multiple diseases. Thus, building an animal model that can help study the independent effects of FSH in vivo is particularly important. In this study, C57BL/6 female mice were ovariectomized and supplemented with estradiol valerate (OVX + E2) to eliminate the effect of the hypothalamic-pituitary-gonadal axis. The OVX + E2 mice received solvent (N.S.) or different doses of recombinant FSH via intraperitoneal injection to create a mouse model (OVF) characterized by relatively stable estrogen and rising FSH levels. Thus, we successfully generated an experimental mouse model to mimic the early stage of menopause transition, characterized by elevated serum FSH levels. The OVF model has the advantages of being stable, low cost, and easy to operate, which is suitable for studies to explore the extragonadal actions of FSH. Here, we describe detailed protocols for the mouse OVF model.

Effect of IGF1 and FSH on the function of granulosa cells from prehierarchal follicles in chickens†.

Insulin-like growth factor 1 (IGF1) is an essential regulator of mammalian follicle development and synergizes with follicle-stimulating hormone (FSH) to amplify its effects. In avian preovulatory follicles, IGF1 increases the expression of genes involved in steroidogenesis and progesterone and inhibin A production. The role of IGF1 in prehierarchal follicles has not been well studied in chickens. The aim of this study was to investigate the role of IGF1 in granulosa cells from prehierarchal follicles and to determine whether IGF1 and FSH synergize to promote follicle development. Granulosa cells of 3-5 and 6-8mm prehierarchal follicles were cultured with IGF1 (0, 10, 100ng/mL) in the presence or absence of FSH (0, 10ng/mL). Cell proliferation, expression of genes important in follicle development (FSHR, IGF1R, AMH, STAR, CYP11A1, INHA, and INHBA), and progesterone production were evaluated following treatment. IGF1 treatment alone significantly increased STAR, CYP11A1, and INHBA mRNA expression and cell proliferation in granulosa cells of 6-8mm follicles. IGF1 and FSH synergized to increase STAR mRNA expression in 6-8mm follicles. IGF1 and FSH co-treatment were necessary to increase INHA mRNA expression in 6-8mm follicles. Although IGF1 significantly increased the expression of genes involved in steroidogenesis, progesterone production in granulosa cells of 6-8mm follicles was not affected. IGF1 did not affect AMH mRNA expression, although FSH significantly decreased AMH expression in granulosa cells of 3-5mm follicles. These results suggest that IGF1 may act with FSH to promote follicle selection at the prehierarchal follicle stage.