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The past decade has witnessed significant advances in our understanding of skeletal homeostasis and the mechanisms that mediate the loss of bone in primary and secondary osteoporosis. Recent breakthroughs have primarily emerged from identifying disease-causing mutations and phenocopying human bone disease in rodents. Notably, using genetically-modified rodent models, disrupting the reciprocal relationship with tropic pituitary hormone and effector hormones, we have learned that pituitary hormones have independent roles in skeletal physiology, beyond their effects exerted through target endocrine glands. The rise of follicle-stimulating hormone (FSH) in the late perimenopause may account, at least in part, for the rapid bone loss when estrogen is normal, while low thyroid-stimulating hormone (TSH) levels may contribute to the bone loss in thyrotoxicosis. Admittedly speculative, suppressed levels of adrenocorticotropic hormone (ACTH) may directly exacerbate bone loss in the setting of glucocorticoid-induced osteoporosis. Furthermore, beyond their established roles in reproduction and lactation, oxytocin and prolactin may affect intergenerational calcium transfer and therefore fetal skeletal mineralization, whereas elevated vasopressin levels in chronic hyponatremic states may increase the risk of bone loss.. Here, we discuss the interaction of each pituitary hormone in relation to its role in bone physiology and pathophysiology., Competing Interests: Declarations. Competing interests: M.Z. is inventor on issued and pending patents on the use of FSH as a target for osteoporosis, obesity and Alzheimer’s disease. M.Z., T.Y. and S.R. are inventors on a pending patent on the formulation of a monoclonal antibody against FSH. The patents will be held by Icahn School of Medicine at Mount Sinai, and M.Z, T.Y. and S.R. would be recipients of royalties, per institutional policy, should the patents be granted. The other authors declare no competing financial interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

High post-menopausal levels of the pituitary gonadotropin follicle-stimulating hormone (FSH) are strongly associated with the onset of Alzheimer's disease (AD). We have shown recently that FSH directly activates the hippocampal FSH receptors (FSHRs) to drive AD-like pathology and memory loss in mice. To unequivocally establish a role for FSH in memory loss, we depleted the Fshr on a 3xTg background and utilized Morris Water Maze to study deficits in spatial memory. 3xTg;Fshr +/+ mice displayed impaired spatial memory at 5 months of age. The loss of memory acquisition and retrieval were both rescued in 3xTg;Fshr -/- mice and, to a lesser extent, in 3xTg;Fshr +/- mice-documenting clear gene-dose-dependent prevention of spatial memory loss. Furthermore, at 5 and 8 months, sham-operated 3xTg;Fshr -/- mice showed better memory performance during the learning and/or retrieval phases, further suggesting that Fshr deletion prevents age-related progression of memory deficits. This prevention was not seen when mice were ovariectomized, except in the 8-month-old 3xTg;Fshr -/- mice. There was also a gene-dose-dependent reduction mainly in the amyloid β40 isoform in whole brain extracts. Finally, serum FSH levels <8 ng/mL in 16-month-old APP/PS1 mice were associated with better retrieval of spatial memory. Collectively, the data provide compelling genetic evidence for a protective effect of inhibiting FSH signaling on the progression of spatial memory deficits in mice and lay a firm foundation for the use of an FSH-blocking agent for the early prevention of memory loss in post-menopausal women., Competing Interests: Competing interests MZ is inventor on issued and pending patients on the use of FSH as a target for osteoporosis, obesity and Alzheimer’s disease. MZ, SR and TY are inventors on a pending patent on an FSH antibody that is formulated at ultrahigh concentration. The patents will be held by the Icahn School of Medicine at Mount Sinai, and MZ, SR and TY would be recipient of royalties, per institutional policy. The other authors declare no competing financial interests. Ethics approval All methods were performed in accordance with the relevant guidelines and regulations. Animal handling and use were compliant with the National Institutes of Health’s Guide for the Care and Use of Laboratory Animals, and approved by the Icahn School of Medicine at Mount Sinai Institutional Animal Care and Use Committee (IACUC Approval # 2018-0047)., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

There is clear evidence that the sympathetic nervous system (SNS) mediates bone metabolism. Histological studies show abundant SNS innervation of the periosteum and bone marrow-these nerves consist of noradrenergic fibers that immunostain for tyrosine hydroxylase, dopamine beta-hydroxylase, or neuropeptide Y. Nonetheless, the brain sites that send efferent SNS outflow to the bone have not yet been characterized. Using pseudorabies (PRV) viral transneuronal tracing, we report, for the first time, the identification of central SNS outflow sites that innervate bone. We find that the central SNS outflow to bone originates from 87 brain nuclei, sub-nuclei, and regions of six brain divisions, namely the midbrain and pons, hypothalamus, hindbrain medulla, forebrain, cerebral cortex, and thalamus. We also find that certain sites, such as the raphe magnus (RMg) of the medulla and periaqueductal gray (PAG) of the midbrain, display greater degrees of PRV152 infection, suggesting that there is considerable site-specific variation in the levels of central SNS outflow to the bone. This comprehensive compendium illustrating the central coding and control of SNS efferent signals to bone should allow for a greater understanding of the neural regulation of bone metabolism, and importantly and of clinical relevance, mechanisms for central bone pain., Competing Interests: VR, DL, KG, SK Reviewing editor, eLife, AG, RW, FK, LC, HK, OM, OB, SS No competing interests declared, TY Senior editor, eLife, MZ consults for Gershon Lehmann, Guidepoint and Coleman groups, (© 2024, Ryu et al.)

Context: Previous studies have shown that the prevalence of polycystic ovary syndrome (PCOS) may vary according to race/ethnicity, although few studies have assessed women of different ethnicities who live in similar geographic and socio-economic conditions., Objective: To determine the prevalence of PCOS in an unselected multiethnic population of premenopausal women., Design: A multicenter prospective cross-sectional study., Settings: The main regional employers of Irkutsk Region and the Buryat Republic, Russia., Participants: During 2016-19, 1398 premenopausal women underwent a history and physical exam, pelvic ultrasound, and testing during a mandatory annual employment-related health assessment., Main Outcome Measures: PCOS prevalence, overall and by ethnicity in a large medically unbiased population, including Caucasian (White), Mongolic or Asian (Buryat), and mixed ethnicity individuals, living in similar geographic and socio-economic conditions for centuries., Results: PCOS was diagnosed in 165/1134 (14.5%) women who had a complete evaluation for PCOS. Based on the probabilities for PCOS by clinical presentation observed in the cohort of women who had a complete evaluation we also estimated the weight-adjusted prevalence of PCOS in 264 women with an incomplete evaluation: 46.2 or 17.5%. Consequently, the total prevalence of PCOS in the population was 15.1%, higher among Caucasians and women of Mixed ethnicity compared to Asians (16.0% and 21.8% vs. 10.8%, pz <0.05)., Conclusions: We observed a 15.1% prevalence of PCOS in our medically unbiased population of premenopausal women. In this population of Siberian premenopausal women of Caucasian, Asian and Mixed ethnicity living in similar geographic and socio-economic conditions, the prevalence was higher in Caucasian or Mixed than Asian women. These data highlight the need to assess carefully ethnic-dependent differences in the frequency and clinical manifestation of PCOS., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

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.

Polycystic ovary syndrome (PCOS) is a highly prevalent disorder in women, and its diagnosis rests on three principal features: ovulatory/menstrual dysfunction, clinical and/or biochemical hyperandrogenism, and polycystic ovarian morphology (PCOM). Currently, data on age- and ethnicity-dependent features of PCOM remain insufficient. We aimed to estimate ethnicity- and age-dependent differences in ovarian volume (OV) and follicle number per ovary (FNPO) in a healthy, medically unbiased population of Caucasian and Asian premenopausal women, who participated in the cross-sectional Eastern Siberia PCOS epidemiology and phenotype (ESPEP) study (ClinicalTrials.gov ID: NCT05194384) in 2016-2019. The study population consisted of 408 non-hirsute, normo-androgenic, eumenorrheic premenopausal women aged 18-44 years. All participants underwent a uniform evaluation including a review of their medical history and a physical examination, blood sampling, and pelvic ultrasonography. The statistical analysis included non-parametric tests and the estimation of the upper normal limits (UNLs) by 98th percentiles for OV and FNPO. In the total study population, the upper OV percentiles did not differ by ethnicity or age group. By contrast, the UNL of FNPO was higher in Caucasian women than in Asian women, and women aged <35 years demonstrated a higher UNL of FNPO compared to older women. In summary, these data suggest that the estimation of FNPO, but not OV, should take into account the ethnicity and age of the individual in estimating the presence of PCOM.

Clinical studies and experimental data together support a role for pituitary gonadotropins, including luteinizing hormone (LH), otherwise considered solely as fertility hormones, in age-related cognitive decline. Furthermore, rising levels of LH in post-menopausal women have been implicated in the high prevalence of mood disorders. This study was designed to examine the effect of deficient LH signaling on both cognitive and emotional behavior in 12-month-old Lhcgr -/- mice. For this, we established and validated a battery of five tests, including Dark-Light Box (DLB), Y-Maze Spontaneous Alternation, Novel Object Recognition (NOR), and contextual and cued Fear Conditioning (FCT) tests. We found that 12-month-old female wild type mice display a prominent anxiety phenotype on DLB and FCT. This phenotype was not seen in 12-month-old female Lhcgr -/- mice, indicating full phenotypic rescue. Furthermore, there was no effect of LHCGR depletion on recognition memory or working spatial memory on NOR and Y-maze testing, respectively, in 12-month-old mice, notwithstanding the absence of a basal phenotype in wild type littermates. The latter data do not exclude an effect of LH on cognition documented in previous studies. Finally, 12-month-old male mice and 3-month-old male and female mice did not consistently display deficits on any test. The data collectively document, for the first time, that loss of LH signaling reverses age-related emotional disturbances, a prelude to future targeted therapies that block LH action., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Seasonal changes in food intake and adiposity in many animal species are triggered by changes in the photoperiod. These latter changes are faithfully transduced into a biochemical signal by melatonin secreted by the pineal gland. Seasonal variations, encoded by melatonin, are integrated by third ventricular tanycytes of the mediobasal hypothalamus through the detection of the thyroid-stimulating hormone (TSH) released from the pars tuberalis. The mediobasal hypothalamus is a critical brain region that maintains energy homeostasis by acting as an interface between the neural networks of the central nervous system and the periphery to control metabolic functions, including ingestive behavior, energy homeostasis, and reproduction. Among the cells involved in the regulation of energy balance and the blood-hypothalamus barrier (BHB) plasticity are tanycytes. Increasing evidence suggests that anterior pituitary hormones, specifically TSH, traditionally considered to have unitary functions in targeting single endocrine sites, display actions on multiple somatic tissues and central neurons. Notably, modulation of tanycytic TSH receptors seems critical for BHB plasticity in relation to energy homeostasis, but this needs to be proven., (© 2023 New York Academy of Sciences.)

Highly concentrated antibody formulations are oftentimes required for subcutaneous, self-administered biologics. Here, we report the development of a unique formulation for our first-in-class FSH-blocking humanized antibody, MS-Hu6, which we propose to move to the clinic for osteoporosis, obesity, and Alzheimer's disease. The studies were carried out using our Good Laboratory Practice (GLP) platform, compliant with the Code of Federal Regulations (Title 21, Part 58). We first used protein thermal shift, size exclusion chromatography, and dynamic light scattering to examine MS-Hu6 concentrations between 1 and 100 mg/mL. We found that thermal, monomeric, and colloidal stability of formulated MS-Hu6 was maintained at a concentration of 100 mg/mL. The addition of the antioxidant L-methionine and chelating agent disodium EDTA improved the formulation's long-term colloidal and thermal stability. Thermal stability was further confirmed by Nano differential scanning calorimetry (DSC). Physiochemical properties of formulated MS-Hu6, including viscosity, turbidity, and clarity, confirmed with acceptable industry standards. That the structural integrity of MS-Hu6 in formulation was maintained was proven through Circular Dichroism (CD) and Fourier Transform Infrared (FTIR) Spectroscopy. Three rapid freeze-thaw cycles at -80 °C/25 °C or -80 °C/37 °C further revealed excellent thermal and colloidal stability. Furthermore, formulated MS-Hu6, particularly its Fab domain, displayed thermal and monomeric storage stability for more than 90 days at 4°C and 25°C. Finally, the unfolding temperature (T m ) for formulated MS-Hu6 increased by >4.80 °C upon binding to recombinant FSH, indicating highly specific ligand binding. Overall, we document the feasibility of developing a stable, manufacturable and transportable MS-Hu6 formulation at a ultra-high concentration at industry standards. The study should become a resource for developing biologic formulations in academic medical centers., Competing Interests: SR Is a co-inventor on a pending patent application relating to the ultra-high formulation of MS-Hu6. These patents are owned by Icahn School of Medicine at Mount Sinai (ISMMS), and the inventors and co-inventors. would be recipients of royalties, per institutional policy, AP, JG, FK, FS, DS, CH, AM, CR, OB, MM, JC No competing interests declared, SK, DL Reviewing editor, eLife, TY, MZ Senior editor, eLife, (© 2023, Rojekar et al.)

Biopharmaceutical products are formulated using several Food and Drug Administration (FDA) approved excipients within the inactive ingredient limit to maintain their storage stability and shelf life. Here, we have screened and optimized different sets of excipient combinations to yield a thermally stable formulation for the humanized follicle-stimulating hormone (FSH)-blocking antibody, MS-Hu6. We used a protein thermal shift assay in which rising temperatures resulted in the maximal unfolding of the protein at the melting temperature (T m ). To determine the buffer and pH for a stable solution, four different buffers with a pH range from 3 to 8 were screened. This resulted in maximal T m s at pH 5.62 for Fab in phosphate buffer and at pH 6.85 for Fc in histidine buffer. Upon testing a range of salt concentrations, MS-Hu6 was found to be more stable at lower concentrations, likely due to reduced hydrophobic effects. Molecular dynamics simulations revealed a higher root-mean-square deviation with 1 mM than with 100 mM salt, indicating enhanced stability, as noted experimentally. Among the stabilizers tested, Tween 20 was found to yield the highest T m and reversed the salt effect. Among several polyols/sugars, trehalose and sucrose were found to produce higher thermal stabilities. Finally, binding of recombinant human FSH to MS-Hu6 in a final formulation (20 mM phosphate buffer, 1 mM NaCl, 0.001% w/v Tween 20, and 260 mM trehalose) resulted in a thermal shift (increase in T m ) for the Fab, but expectedly not in the Fc domain. Given that we used a low dose of MS-Hu6 (1 μM), the next challenge would be to determine whether 100-fold higher, industry-standard concentrations are equally stable., (© 2023 New York Academy of Sciences.)

The past decade has seen significant advances in our understanding of skeletal homeostasis and the mechanisms that mediate the loss of bone integrity in disease. Recent breakthroughs have arisen mainly from identifying disease-causing mutations and modeling human bone disease in rodents, in essence, highlighting the integrative nature of skeletal physiology. It has become increasingly clear that bone cells, osteoblasts, osteoclasts, and osteocytes, communicate and regulate the fate of each other through RANK/RANKL/OPG, liver X receptors (LXRs), EphirinB2-EphB4 signaling, sphingolipids, and other membrane-associated proteins, such as semaphorins. Mounting evidence also showed that critical developmental pathways, namely, bone morphogenetic protein (BMP), NOTCH, and WNT, interact each other and play an important role in postnatal bone remodeling. The skeleton communicates not only with closely situated organs, such as bone marrow, muscle, and fat, but also with remote vital organs, such as the kidney, liver, and brain. The metabolic effect of bone-derived osteocalcin highlights a possible role of skeleton in energy homeostasis. Furthermore, studies using genetically modified rodent models disrupting the reciprocal relationship with tropic pituitary hormone and effector hormone have unraveled an independent role of pituitary hormone in skeletal remodeling beyond the role of regulating target endocrine glands. The cytokine-mediated skeletal actions and the evidence of local production of certain pituitary hormones by bone marrow-derived cells displays a unique endocrine-immune-skeletal connection. Here, we discuss recently elucidated mechanisms controlling the remodeling of bone, communication of bone cells with cells of other lineages, crosstalk between bone and vital organs, as well as opportunities for treating diseases of the skeleton., Competing Interests: MZ Deputy Editor, eLife, SK, MM, FK, FS, SM, AG, TF, OM, OB, AP, SR, JC, VR, TD, DL, CR No competing interests declared, YG, TY Reviewing Editor, eLife, (© 2023, Zaidi et al.)

Androgen assessment is a key element for diagnosing polycystic ovary syndrome (PCOS), and defining a "normal" level of circulating androgens is critical for epidemiological studies. We determined the upper normal limits (UNLs) for androgens in a population-based group of premenopausal "healthy control" women, overall and by ethnicity (Caucasian and Asian), in the cross-sectional Eastern Siberia PCOS Epidemiology and Phenotype (ESPEP) Study (ClinicalTrials.gov ID: NCT05194384) conducted in 2016-2019. Overall, we identified a "healthy control" group consisting of 143 healthy premenopausal women without menstrual dysfunction, hirsutism, polycystic ovaries, or medical disorders. We analyzed serum total testosterone (TT) by using liquid chromatography with tandem mass spectrometry (LC-MS/MS), and DHEAS, sex-hormone-binding globulin (SHBG), TSH, prolactin, and 17-hydroxyprogesterone (17OHP) were assessed with an enzyme-linked immunosorbent assay (ELISA). The UNLs for the entire population for the TT, free androgen index (FAI), and DHEAS were determined as the 98th percentiles in healthy controls as follows: 67.3 (95% confidence interval (CI): 48.1, 76.5) ng/dl, 5.4 (3.5, 14.0), and 355 (289, 371) μg/dl, respectively. The study results demonstrated that the UNLs for TT and FAI varied by ethnicity, whereas the DHEAS UNLs were comparable in the ethnicities studied.

Over the past years, pituitary hormones and their receptors have been shown to have non-traditional actions that allow them to bypass the hypothalamus-pituitary-effector glands axis. Bone cells-osteoblasts and osteoclasts-express receptors for growth hormone, follicle stimulating hormone (FSH), thyroid stimulating hormone (TSH), adrenocorticotrophic hormone (ACTH), prolactin, oxytocin, and vasopressin. Independent skeletal actions of pituitary hormones on bone have been studied using genetically modified mice with haploinsufficiency and by activating or inactivating the receptors pharmacologically, without altering systemic effector hormone levels. On another front, the discovery of a TSH variant (TSH-βv) in immune cells in the bone marrow and skeletal action of FSHβ through tumor necrosis factor α provides new insights underscoring the integrated physiology of bone-immune-endocrine axis. Here we discuss the interaction of each pituitary hormone with bone and the potential it holds in understanding bone physiology and as a therapeutic target.

Pharmacological and genetic studies over the past decade have established the follicle-stimulating hormone (FSH) as an actionable target for diseases affecting millions, namely osteoporosis, obesity, and Alzheimer's disease. Blocking FSH action prevents bone loss, fat gain, and neurodegeneration in mice. We recently developed a first-in-class, humanized, epitope-specific FSH-blocking antibody, MS-Hu6, with a K D of 7.52 nM. Using a Good Laboratory Practice (GLP)-compliant platform, we now report the efficacy of MS-Hu6 in preventing and treating osteoporosis in mice and parameters of acute safety in monkeys. Biodistribution studies using 89 Zr-labeled, biotinylated or unconjugated MS-Hu6 in mice and monkeys showed localization to bone and bone marrow. The MS-Hu6 displayed a β phase t ½ of 7.5 days (180 hr) in humanized Tg32 mice. We tested 217 variations of excipients using the protein thermal shift assay to generate a final formulation that rendered MS-Hu6 stable in solution upon freeze-thaw and at different temperatures, with minimal aggregation, and without self-, cross-, or hydrophobic interactions or appreciable binding to relevant human antigens. The MS-Hu6 showed the same level of "humanness" as human IgG1 in silico and was non-immunogenic in ELISpot assays for IL-2 and IFN-γ in human peripheral blood mononuclear cell cultures. We conclude that MS-Hu6 is efficacious, durable, and manufacturable, and is therefore poised for future human testing., Competing Interests: SG, TK, AG, FK, DS, VD, KS, AP, GP, JM, AT, Mv, TP, JF, JN, FS, ES, SR, PK, LC, JC, AP, SM, HK, MB, PS, KI, VM, RB, CR, AM, SH, MS, MM, JC, MN, VR, SK, JC, NZ, ZF, DL, CR No competing interests declared, JI, TY Reviewing editor, eLife, MZ is an inventor on issued patents on inhibiting FSH for the prevention and treatment of osteoporosis and obesity (U.S. Patent 8,435,948 and 11,034,761). M.Z. is also an inventor on pending patent application on composition and use of humanized monoclonal anti-FSH antibodies, and is co-inventor of a pending patent on the use of FSH as a target for preventing Alzheimer's disease. These patents are owned by Icahn School of Medicine at Mount Sinai (ISMMS), and M.Z. would be recipient of royalties, per institutional policy. M.Z. also consults for several financial platforms, including Gerson Lehman Group and Guidepoint, on drugs for osteoporosis and genetic bone diseases. Deputy editor, eLife, (© 2022, Gera, Kuo, Gumerova et al.)

There is increasing evidence that anterior pituitary hormones, traditionally thought to have unitary functions in regulating single endocrine targets, act on multiple somatic tissues, such as bone, fat, and liver. There is also emerging evidence for anterior pituitary hormone action on brain receptors in mediating central neural and peripheral somatic functions. Here, we have created the most comprehensive neuroanatomical atlas on the expression of TSHR, LHCGR, and FSHR. We have used RNAscope, a technology that allows the detection of mRNA at single-transcript level, together with protein level validation, to document Tshr expression in 173 and Fshr expression in 353 brain regions, nuclei and subnuclei identified using the Atlas for the Mouse Brain in Stereotaxic Coordinates . We also identified Lhcgr transcripts in 401 brain regions, nuclei and subnuclei. Complementarily, we used ViewRNA, another single-transcript detection technology, to establish the expression of FSHR in human brain samples, where transcripts were co-localized in MALAT1 -positive neurons. In addition, we show high expression for all three receptors in the ventricular region-with yet unknown functions. Intriguingly, Tshr and Fshr expression in the ependymal layer of the third ventricle was similar to that of the thyroid follicular cells and testicular Sertoli cells, respectively. In contrast, Fshr was localized to NeuN-positive neurons in the granular layer of the dentate gyrus in murine and human brain-both are Alzheimer's disease-vulnerable regions. Our atlas thus provides a vital resource for scientists to explore the link between the stimulation or inactivation of brain glycoprotein hormone receptors on somatic function. New actionable pathways for human disease may be unmasked through further studies., Competing Interests: VR, AG, FK, SK, PK, SM, HK, LC, PC, TK, AP, FS, SW, NK, SZ, SK, MN, CR, KG, TF, DL No competing interests declared, VH has received consultation fees from Synaptec to Cold Spring Harbor Laboratories, KY, TY Reviewing editor, eLife, TD has received payments from Kronus Inc, Starr, ID as a Board member and for various books and ebooks, MZ Senior editor, eLife, (© 2022, Ryu et al.)

Alzheimer's disease has a higher incidence in older women, with a spike in cognitive decline that tracks with visceral adiposity, dysregulated energy homeostasis and bone loss during the menopausal transition 1,2 . Inhibiting the action of follicle-stimulating hormone (FSH) reduces body fat, enhances thermogenesis, increases bone mass and lowers serum cholesterol in mice 3-7 . Here we show that FSH acts directly on hippocampal and cortical neurons to accelerate amyloid-β and Tau deposition and impair cognition in mice displaying features of Alzheimer's disease. Blocking FSH action in these mice abrogates the Alzheimer's disease-like phenotype by inhibiting the neuronal C/EBPβ-δ-secretase pathway. These data not only suggest a causal role for rising serum FSH levels in the exaggerated Alzheimer's disease pathophysiology during menopause, but also reveal an opportunity for treating Alzheimer's disease, obesity, osteoporosis and dyslipidaemia with a single FSH-blocking agent., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Thyrotropin (TSH), traditionally seen as a pituitary hormone that regulates thyroid glands, has additional roles in physiology including skeletal remodeling. Population-based observations in people with euthyroidism or subclinical hyperthyroidism indicated a negative association between bone mass and low-normal TSH. The findings of correlative studies were supported by small intervention trials using recombinant human TSH (rhTSH) injection, and genetic and case-based evidence. Genetically modified mouse models, which disrupt the reciprocal relationship between TSH and thyroid hormone, have allowed us to examine an independent role of TSH. Since the first description of osteoporotic phenotype in haploinsufficient Tshr +/- mice with normal thyroid hormone levels, the antiosteoclastic effect of TSH has been documented in both in vitro and in vivo studies. Further studies showed that increased osteoclastogenesis in Tshr-deficient mice was mediated by tumor necrosis factor α. Low TSH not only increased osteoclastogenesis, but also decreased osteoblastogenesis in bone marrow-derived primary osteoblast cultures. However, later in vivo studies using small and intermittent doses of rhTSH showed a proanabolic effect, which suggests that its action might be dose and frequency dependent. TSHR was shown to interact with insulin-like growth factor 1 receptor, and vascular endothelial growth factor and Wnt pathway might play a role in TSH's effect on osteoblasts. The expression and direct skeletal effect of a biologically active splice variant of the TSHβ subunit (TSHβv) in bone marrow-derived macrophage and other immune cells suggest a local skeletal effect of TSHR. Further studies of how locally secreted TSHβv and systemic TSHβ interact in skeletal remodeling through the endocrine, immune, and skeletal systems will help us better understand the hyperthyroidism-induced bone disease., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Cardiovascular disease (CVD) and osteoporosis often occur together, suggesting an association between CVD and bone loss. Similarly, the correlation of bone loss, atherosclerosis, and aortic calcification, especially in patients with chronic kidney disease, exemplifies a bone-vessel connection. In this issue of the JCI, Santhanam et al. investigated the role of the angiogenesis factor platelet-derived growth factor-BB (PDGF-BB) in vascular stiffening. Serum levels of bone-derived PDGF-BB differed between young and aged mice, and in mice fed a high-fat diet (HFD) compared with those fed normal chow. Experiments with genetic models led the authors to conclude that bone-derived PDGF-BB mediates the hallmark arterial stiffening of aging and metabolic stress. Notably, excessive preosteoclast-derived PDGF-BB production during aging inhibited osteoblastic bone formation and increased circulating PDGF-BB, which in turn, accelerated vascular stiffness. These findings suggest that modifying circulating PDGF-BB levels may benefit patients with CVD, osteoporosis, and other age-related diseases.

Background: Erythroblast erythroferrone (ERFE) secretion inhibits hepcidin expression by sequestering several bone morphogenetic protein (BMP) family members to increase iron availability for erythropoiesis., Methods: To address whether ERFE functions also in bone and whether the mechanism of ERFE action in bone involves BMPs, we utilize the Erfe -/- mouse model as well as β-thalassemic ( Hbb th3/+ ) mice with systemic loss of ERFE expression. In additional, we employ comprehensive skeletal phenotyping analyses as well as functional assays in vitro to address mechanistically the function of ERFE in bone., Results: We report that ERFE expression in osteoblasts is higher compared with erythroblasts, is independent of erythropoietin, and functional in suppressing hepatocyte hepcidin expression. Erfe -/- mice display low-bone-mass arising from increased bone resorption despite a concomitant increase in bone formation. Consistently, Erfe -/- osteoblasts exhibit enhanced mineralization, Sost and Rankl expression, and BMP-mediated signaling ex vivo. The ERFE effect on osteoclasts is mediated through increased osteoblastic RANKL and sclerostin expression, increasing osteoclastogenesis in Erfe -/- mice. Importantly, Erfe loss in Hbb th3/+ mice, a disease model with increased ERFE expression, triggers profound osteoclastic bone resorption and bone loss., Conclusions: Together, ERFE exerts an osteoprotective effect by modulating BMP signaling in osteoblasts, decreasing RANKL production to limit osteoclastogenesis, and prevents excessive bone loss during expanded erythropoiesis in β-thalassemia., Funding: YZG acknowledges the support of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (R01 DK107670 to YZG and DK095112 to RF, SR, and YZG). MZ acknowledges the support of the National Institute on Aging (U19 AG60917) and NIDDK (R01 DK113627). TY acknowledges the support of the National Institute on Aging (R01 AG71870). SR acknowledges the support of NIDDK (R01 DK090554) and Commonwealth Universal Research Enhancement (CURE) Program Pennsylvania., Competing Interests: MC, SG, MR, MF, AG, MP, CC, VS, CC, SK, EN, RF, SR, DL, TY, YG No competing interests declared, VO, HH is affiliated with Intrinsic Lifesciences, LLC. The author has no other competing interests to declare. MZ Deputy editor, eLife, (© 2021, Castro-Mollo et al.)

Blocking the action of FSH genetically or pharmacologically in mice reduces body fat, lowers serum cholesterol, and increases bone mass, making an anti-FSH agent a potential therapeutic for three global epidemics: obesity, osteoporosis, and hypercholesterolemia. Here, we report the generation, structure, and function of a first-in-class, fully humanized, epitope-specific FSH blocking antibody with a K D of 7 nM. Protein thermal shift, molecular dynamics, and fine mapping of the FSH-FSH receptor interface confirm stable binding of the Fab domain to two of five receptor-interacting residues of the FSHβ subunit, which is sufficient to block its interaction with the FSH receptor. In doing so, the humanized antibody profoundly inhibited FSH action in cell-based assays, a prelude to further preclinical and clinical testing., Competing Interests: The authors declare no competing interest.

Today, research in biomedicine often requires the knowledge and technologies in diverse fields. Therefore, there is an increasing need for collaborative team science that crosses traditional disciplines. Here, we discuss our own lessons from both interdisciplinary and transdisciplinary teams, which ultimately ushered us to expand our research realm beyond bone biology., (© 2020 Orthopaedic Research Society. Published by Wiley Periodicals LLC.)

We report that two widely-used drugs for erectile dysfunction, tadalafil and vardenafil, trigger bone gain in mice through a combination of anabolic and antiresorptive actions on the skeleton. Both drugs were found to enhance osteoblastic bone formation in vivo using a unique gene footprint and to inhibit osteoclast formation. The target enzyme, phosphodiesterase 5A (PDE5A), was found to be expressed in mouse and human bone as well as in specific brain regions, namely the locus coeruleus, raphe pallidus, and paraventricular nucleus of the hypothalamus. Localization of PDE5A in sympathetic neurons was confirmed by coimmunolabeling with dopamine β-hydroxylase, as well as by retrograde bone-brain tracing using a sympathetic nerve-specific pseudorabies virus, PRV152. Both drugs elicited an antianabolic sympathetic imprint in osteoblasts, but with net bone gain. Unlike in humans, in whom vardenafil is more potent than tadalafil, the relative potencies were reversed with respect to their osteoprotective actions in mice. Structural modeling revealed a higher binding energy of tadalafil to mouse PDE5A compared with vardenafil, due to steric clashes of vardenafil with a single methionine residue at position 806 in mouse PDE5A. Collectively, our findings suggest that a balance between peripheral and central actions of PDE5A inhibitors on bone formation together with their antiresorptive actions specify the osteoprotective action of PDE5A blockade., Competing Interests: The authors declare no competing interest.

The primitive neurohypophyseal nonapeptide oxytocin (OXT) has established functions in parturition, lactation, appetite, and social behavior. We have shown that OXT has direct actions on the mammalian skeleton, stimulating bone formation by osteoblasts and modulating the genesis and function of bone-resorbing osteoclasts. We deleted OXT receptors (OXTRs) selectively in osteoblasts and osteoclasts using Col2.3Cre and Acp5Cre mice, respectively. Both male and female Col2.3Cre + : Oxtr fl/fl mice recapitulate the low-bone mass phenotype of Oxtr +/- mice, suggesting that OXT has a prominent osteoblastic action in vivo. Furthermore, abolishment of the anabolic effect of estrogen in Col2.3Cre + : Oxtr fl/fl mice suggests that osteoblastic OXTRs are necessary for estrogen action. In addition, the high bone mass in Acp5Cre + : Oxtr fl/fl mice indicates a prominent action of OXT in stimulating osteoclastogenesis. In contrast, we found that in pregnant and lactating Col2.3Cre + : Oxtr fl/fl mice, elevated OXT inhibits bone resorption and rescues the bone loss otherwise noted during pregnancy and lactation. However, OXT does not contribute to ovariectomy-induced bone loss. Finally, we show that OXT acts directly on OXTRs on adipocytes to suppress the white-to-beige transition gene program. Despite this direct antibeiging action, injected OXT reduces total body fat, likely through an action on OXT-ergic neurons. Consistent with an antiobesity action of OXT, Oxt -/- and Oxtr -/- mice display increased total body fat. Overall, the actions of OXT on bone mass and body composition provide the framework for future therapies for osteoporosis and obesity.

The traditional view of follicle - stimulating hormone (FSH) as a reproductive hormone is changing. It has been shown that FSH receptors (FSHRs) are expressed in various extra-gonadal tissues and mediate the biological effects of FSH at those sites. Molecular, animal, epidemiologic, and clinical data suggest that elevated serum FSH may play a significant role in the evolution of bone loss and obesity, as well as contributing to cardiovascular and cancer risk. This review summarizes recent data on FSH action beyond reproduction.

The lysosomal enzyme glucocerebrosidase-1 (GCase) catalyzes the cleavage of a major glycolipid glucosylceramide into glucose and ceramide. The absence of fully functional GCase leads to the accumulation of its lipid substrates in lysosomes, causing Gaucher disease, an autosomal recessive disorder that displays profound genotype-phenotype nonconcordance. More than 250 disease-causing mutations in GBA1 , the gene encoding GCase, have been discovered, although only one of these, N370S, causes 70% of disease. Here, we have used a knowledge-based docking protocol that considers experimental data of protein-protein binding to generate a complex between GCase and its known facilitator protein saposin C (SAPC). Multiscale molecular-dynamics simulations were used to study lipid self-assembly, membrane insertion, and the dynamics of the interactions between different components of the complex. Deep learning was applied to propose a model that explains the mechanism of GCase activation, which requires SAPC. Notably, we find that conformational changes in the loops at the entrance of the substrate-binding site are stabilized by direct interactions with SAPC and that the loss of such interactions induced by N370S and another common mutation, L444P, result in destabilization of the complex and reduced GCase activation. Our findings provide an atomistic-level explanation for GCase activation and the precise mechanism through which N370S and L444P cause Gaucher disease., Competing Interests: The authors declare no conflict of interest.

Polycystic ovary syndrome (PCOS) affects around 10% of women of reproductive age and is most common in developed countries. The aetiology of PCOS is not completely understood. Current evidence suggests that the syndrome results from a genetic predisposition interacting with developmental events during fetal or perinatal life that together increase susceptibility in some individuals. This implies that environmental factors influence the initiation of PCOS in the fetus or infant, either directly or via the mother. PCOS is often considered to be an ancient disorder but there is no direct proof of this in the medical or historic record. One of the cardinal features, polycystic ovaries, was first described only in the early 1900s, despite reports of many thousands of autopsies recorded earlier. This conundrum could be explained by postulating that polycystic ovaries were rare before the 1900s and have become more common over the last 100 years. The hypothesis that PCOS is a syndrome of the 20th Century would eliminate the need to explain the paradox of why there exists a genetic predisposition to subfertility syndrome., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Study Question: Are non-esterified fatty acid (NEFA) kinetics altered in women with polycystic ovary syndrome (PCOS)?, Summary Answer: Women with PCOS, particularly obese subjects, have dysregulated plasma NEFA kinetics in response to changes in plasma insulin and glucose levels, which are associated with insulin resistance (IR) independently of the fasting plasma NEFA levels., What Is Known Already: Elevated plasma NEFA levels are associated with IR in many disorders, although the homeostasis of NEFA kinetics and its relationship to IR in women with PCOS is unknown., Study Design, Size, Duration: We prospectively compared insulin sensitivity and NEFA kinetics in 29 PCOS and 29 healthy controls women matched for BMI., Participants/materials, Setting, Methods: This study was conducted in a tertiary institution. Plasma NEFA, glucose and insulin levels were assessed during a modified frequently sampled intravenous glucose tolerance test (mFSIVGTT). Minimal models were used to assess insulin sensitivity (Si) and NEFA kinetics (i.e. model-derived initial plasma NEFA level [NEFA0], phi constant [Φ], reflecting glucose-mediated inhibition of lipolysis and measures of maximum rate of lipolysis [SFFA] and NEFA uptake from plasma [KFFA])., Main Results and the Role of Chance: The study provides new evidence that women with PCOS have defective NEFA kinetics characterized by: (i) lower basal plasma NEFA levels, measured directly and modeled (NEFA0), and (ii) a greater glucose-mediated inhibition of lipolysis in the remote or interstitial space (reflected by a lower affinity constant [Φ]). There were no differences, however, in the maximal rates of adipose tissue lipolysis (SFFA) and the rate at which NEFA leaves the plasma pool (KFFA). The differences observed in NEFA kinetics were exacerbated, and almost exclusively observed, in the obese PCOS subjects., Limitations, Reasons for Caution: Our study did not study NEFA subtypes. It was also cross-sectional and based on women affected by PCOS as defined by the 1990 National Institutes of Health (NIH) criteria (i.e. Phenotypes A and B) and identified in the clinical setting. Consequently, extrapolation of the present data to other phenotypes of PCOS should be made with caution. Furthermore, our data is exploratory and therefore requires validation with a larger sample size., Wider Implications of the Findings: Dysfunction in NEFA kinetics may be a marker of metabolic dysfunction in nondiabetic obese women with PCOS and may be more important than simply assessing circulating NEFA levels at a single point in time for understanding the mechanism(s) underlying the IR of PCOS., Study Funding/competing Interest(s): This work was supported by NIH grants R01-DK073632 and R01-HD29364 to R.A.; a Career Development Award from MD Medical Group, Moscow, RF, to D.L. and Augusta University funds to Y.-H.C. RA serves as consultant to Ansh Labs, Medtronics, Spruce Biosciences and Latitude Capital. U.E., Z.A., D.L., R.M., Y.-H.C., R.C.B. and Y.D.I.C. have no competing interests to declare., Trial Registration Number: Not applicable.

Objective: To test the hypothesis that the polycystic ovary syndrome (PCOS) phenotype, or its component features, is less severe in adolescents than in young adult patients, in a referred (clinical) population., Design: Cross-sectional study., Setting: Tertiary-care academic medical center., Patient(s): Two hundred seventy-four adolescents and young adults aged 13.0-24.9 years with PCOS according to the National Institute of Health 1990 criteria. Patients were categorized as adolescents (AD: 13.0-18.9 years; n = 91) and young adults (YA: 19.0-24.9 years; n = 183). Adolescents were further categorized as early adolescents (Early-AD: 13.0-15.9 years; n = 31) and late adolescents (Late-AD: 16.0-18.9 years; n = 60)., Intervention(s): History, physical examination, hormonal assays with the use of standardized protocols., Main Outcome Measure(s): Unadjusted and adjusted odds ratios (ORs; adjusted for body mass index [BMI] when applicable) were calculated for biochemical hyperandrogenism (HA), hirsutism (HIR), acne, and degree of oligo/amenorrhea (OA). PCOS phenotypes were classified as HIR+HA+OA, HA+OA, and HIR+OA., Result(s): Our analysis demonstrated minimal significant difference in the prevalence of the three PCOS phenotypes, or component features, between AD and YA patients. The risks for obesity were higher for YA versus AD, and the risk of acne was lower for YA versus AD. There was no significant difference between Early-AD and Late-AD. BMI-adjusted models did not significantly modify the main findings., Conclusion(s): The present study suggests that the PCOS phenotype is established in early adolescence, remains constant into adulthood, and is not related to BMI., (Copyright © 2018 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

The polycystic ovary syndrome (PCOS) is a common and important complex endocrine metabolic disorder affecting women mainly in the reproductive age. The prevalence of the disorder varies depending on the epidemiologic design and criterion used to study the disease. This variation in methodology and subsequent effect on epidemiologic estimate makes it difficult to compare prevalences and phenotypes across geographical areas and assess the effect of cultural and racial variations on PCOS phenotypes. Overall, there is an urgent need for a globally accepted standardized protocol for epidemiologic studies of PCOS, which will maximize the comparability of studies around the globe. To address this issue the Androgen Excess and PCOS Society, Inc. has designated an expert Task Force to draft recommendations to guide epidemiologic research worldwide. Once completed, the use of such recommendations will enable epidemiologists to the effects of geographical and cultural variations of PCOS prevalence and assist in determining the phenotype-genotype associations in the disorder. Further, it will assist in developing informed, and thus effective, public health policy. In essence, the need to standardize epidemiologic studies across the globe is pressing and urgent.

The primary objective of the Ghana Polycystic Ovary Syndrome Epidemiology and Phenotype (Ghana-PEP) study will be to assess the relevance and phenotypic distribution of polycystic ovarian syndrome (PCOS) in a medically unbiased population of reproductive-aged women. In addition, the study will also attempt to identify sociodemographic, environmental, and psychological factors that may play a role in the development of PCOS phenotype. The study aims to recruit 990 randomly selected women aged 18-45 years living in Nsawam, the district capital of the Nsawam-Adoagyiri Municipality, in the Eastern region of Ghana. Participants will complete a questionnaire with the aid of trained personnel, undergo a physical examination, and undergo ultrasonography and biochemical evaluations relevant to PCOS. It is anticipated that the study will provide the population prevalence and phenotypes, and distribution of PCOS., (© 2018 International Federation of Gynecology and Obstetrics.)

Bone loss in women accelerates during perimenopause, and continues into old age. To-date, there has been little progress made in stratifying for fracture risk in premenopausal and early postmenopausal women. Epidemiologic data suggests that changes in serum FSH could predict decrements in bone mass during peri- and postmenopause. In bone, FSH stimulates osteoclast formation by releasing osteoclastogenic cytokines. Here, we address the evidence for bone loss across the menopausal transition, discuss strategies for detection and treatment of early postmenopausal osteoporosis, and describe the role FSH plays in physiology and likely in pathophysiology of early postmenopausal bone loss., (Copyright © 2018. Published by Elsevier B.V.)

The Study of Women's Health Across the Nation has taught us that impending ovarian failure during late perimenopause is associated with a sharp rise in serum FSH, which coincides with the most rapid rate of bone loss and the onset of visceral adiposity. At this time in a woman's life, serum estrogen levels are largely unaltered, so the hypothesis that hypoestrogenemia is the sole cause of bone loss and visceral obesity does not offer a full explanation. An alternative explanation, arising from animal models and human data, is that both physiologic aberrations, obesity and osteoporosis, arise at least in part from rising FSH levels. Here, we discuss recent findings on the mechanism through which FSH exerts biological actions on bone and fat and review clinical data that support a role for FSH in causing osteoporosis and obesity. We will also provide a conceptual framework for using a single anti-FSH agent to prevent and treat both osteoporosis and obesity in women across the menopausal transition.

Pituitary hormones have long been thought solely to regulate single targets. Challenging this paradigm, we discovered that both anterior and posterior pituitary hormones, including FSH, had other functions in physiology. We have shown that FSH regulates skeletal integrity, and, more recently, find that FSH inhibition reduces body fat and induces thermogenic adipose tissue. A polyclonal antibody raised against a short, receptor-binding epitope of FSHβ was found not only to rescue bone loss postovariectomy, but also to display marked antiobesity and probeiging actions. Questioning whether a single agent could be used to treat two medical conditions of public health importance--osteoporosis and obesity--we developed two further monoclonal antibodies, Hf2 and Mf4, against computationally defined receptor-binding epitopes of FSHβ. Hf2 has already been shown to reduce body weight and fat mass and cause beiging in mice on a high-fat diet. Here, we show that Hf2, which binds mouse Fsh in immunoprecipitation assays, also increases cortical thickness and trabecular bone volume, and microstructural parameters, in sham-operated and ovariectomized mice, noted on microcomputed tomography. This effect was largely recapitulated with Mf4, which inhibited bone resorption by osteoclasts and stimulated new bone formation by osteoblasts. These effects were exerted in the absence of alterations in serum estrogen in wild-type mice. We also reconfirm the existence of Fshrs in bone by documenting the specific binding of fluorescently labeled FSH, FSH-CH, in vivo. Our study provides the framework for the future development of an FSH-based therapeutic that could potentially target both bone and fat., Competing Interests: The authors declare no conflict of interest.

Context: Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic abnormality with a worldwide prevalence of 4% to 21%, depending on diagnostic criteria. The National Institutes of Health (NIH) is the largest single funding agency in the world; it invests nearly $30.0 billion annually in biomedical research., Evidence Acquisition: Using the NIH Research Portfolio Online Reporting tool, we searched for all grants awarded by the NIH for PCOS and three other disorders with similar degrees of morbidity and similar or lower mortality and prevalence [rheumatoid arthritis (RA), tuberculosis (TB), and systemic lupus erythematosus (SLE)]., Evidence Synthesis: We compared funding by the NIH for PCOS, RA, TB, and SLE research for the years 2006 to 2015, inclusive., Conclusion: PCOS, compared with RA, TB, and SLE, was relatively less funded (total mean 10-year funding was $215.12 million vs $454.39 million, $773.77 million, and $609.52 million, respectively). Funding for PCOS was largely provided by one NIH Institute/Center (ICs) vs at least two ICs for SLE and RA; more individual Research Project Grants were awarded for RA, SLE, and TB than for PCOS, whereas PCOS funding was more likely to be through General Clinical Research Centers Program or Specialized Centers Program awards. Our data suggest that PCOS research may be underfunded considering its prevalence, economic burden, metabolic morbidity, and negative impact on quality of life. Greater education of NIH leaders, including those at the National Heart, Lung, and Blood Institute and National Institutes of Diabetes and Digestive and Kidney Diseases; other federal and state agency leads; elected leaders; and the general public by professional societies, the scientific community, and patient advocates regarding this disorder is needed., (Copyright © 2017 Endocrine Society)

This review discusses the current state of our understanding regarding the genetic basis of the most important reproductive disorders in women. For clarity, these disorders have been divided into eugonadal and hypogonadal types. Hypogonadal disorders have been further subdivided according to serum gonadotropin levels. Our review focuses on historical and recent data regarding the genetics of the hypothalamic-pituitary-gonadal axis dysfunction, as well as the development and etiology of eugonadal disorders including leiomyomata, endometriosis, spontaneous ovarian hyperstimulation syndrome, polycystic ovarian syndrome, mullerian aplasia, and steroid hormone resistance syndromes. We discuss the known genes most commonly involved in hypergonadotropic hypogonadism (Turner syndrome and premature ovarian failure) and hypogonadotrophic hypogonadism (Kallmann syndrome and normosmic types). In addition, we summarize the current clinical testing approaches and their utility in practical application., (Copyright © 2017. Published by Elsevier Ltd.)

Introduction: Polycystic ovary syndrome (PCOS) is a hormonal and metabolic disorder affecting 5 to 20% of reproductive-aged women worldwide that results in androgen excess, menstrual dysfunction and oligo-ovulatory subfertility, with increased risks for type 2 diabetes, endometrial adenocarcinoma, and potentially vascular disease, among other morbidities. PCOS is a complex genetic trait with strong heritability accounting for as high as 70% of the development of the disorder. Areas covered: The authors summarize the historical and recent findings of genetic studies of PCOS, such as familial studies, twin studies, and molecular genetic studies, including the results of recent genome wide associated studies. PubMed, Medline and Embase database were used to search relevant articles. Included studies were predominately conducted in Asia, North Africa, North America, and Europe. Expert commentary: Current studies aim to establish the role and function of identified genes; such efforts could serve as potential platforms for novel diagnostic and treatments for PCOS patients. The etiology of PCOS will be better understood as more data is gathered systematically, subjects are better phenotyped larger populations are recruited, and a better understanding of the role of genetic architecture, genetic variation, epigenetics, and gene-gene, gene-environment, and gene-phenotype interaction is obtained.

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Objective: To compare the prevalence of polycystic ovary syndrome (PCOS) phenotypes and obesity among patients detected in referral versus unselected populations., Design: Systematic review and meta-analysis., Setting: Not applicable., Patient(s): Thirteen thousand seven hundred ninety-six reproductive-age patients with PCOS, as defined by the extended Rotterdam 2003 criteria., Intervention(s): Review of PUBMED, EMBASE, and Cochrane Library, 2003-2016. Only observational studies were included. Data were extracted using a web-based, piloted form and combined for meta-analysis., Main Outcome Measure(s): PCOS phenotypes were classified as follows: phenotype A, clinical and/or biochemical hyperandrogenism (HA) + oligo-/anovulation (OA) + polycystic ovarian morphology (PCOM); phenotype B, HA+OA; phenotype C, HA+PCOM; and phenotype D, OA+PCOM., Result(s): Forty-one eligible studies, reporting on 43 populations, were identified. Pooled estimates of detected PCOS phenotype prevalence were consequently documented in referral versus unselected populations, as [1] phenotype A, 50% (95% confidence interval [CI], 46%-54%) versus 19% (95% CI, 13%-27%); [2] phenotype B, 13% (95% CI, 11%-17%) versus 25% (95% CI, 15%-37%); [3] phenotype C, 14% (95% CI, 12%-16%) versus 34% (95% CI, 25-46%); and [4] phenotype D, 17% (95% CI, 13%-22%) versus 19% (95% CI, 14%-25%). Differences between referral and unselected populations were statistically significant for phenotypes A, B, and C. Referral PCOS subjects had a greater mean body mass index (BMI) than local controls, a difference that was not apparent in unselected PCOS., Conclusion(s): The prevalence of more complete phenotypes in PCOS and mean BMI were higher in subjects identified in referral versus unselected populations, suggesting the presence of significant referral bias., (Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Androgen excess (AE) is a key feature of polycystic ovary syndrome (PCOS) and results in, or contributes to, the clinical phenotype of these patients. Although AE will contribute to the ovulatory and menstrual dysfunction of these patients, the most recognizable sign of AE includes hirsutism, acne, and androgenic alopecia or female pattern hair loss (FPHL). Evaluation includes not only scoring facial and body terminal hair growth using the modified Ferriman-Gallwey method but also recording and possibly scoring acne and alopecia. Moreover, assessment of biochemical hyperandrogenism is necessary, particularly in patients with unclear or absent hirsutism, and will include assessing total and free testosterone (T), and possibly dehydroepiandrosterone sulfate (DHEAS) and androstenedione, although these latter contribute limitedly to the diagnosis. Assessment of T requires use of the highest quality assays available, generally radioimmunoassays with extraction and chromatography or mass spectrometry preceded by liquid or gas chromatography. Management of clinical hyperandrogenism involves primarily either androgen suppression, with a hormonal combination contraceptive, or androgen blockade, as with an androgen receptor blocker or a 5α-reductase inhibitor, or a combination of the two. Medical treatment should be combined with cosmetic treatment including topical eflornithine hydrochloride and short-term (shaving, chemical depilation, plucking, threading, waxing, and bleaching) and long-term (electrolysis, laser therapy, and intense pulse light therapy) cosmetic treatments. Generally, acne responds to therapy relatively rapidly, whereas hirsutism is slower to respond, with improvements observed as early as 3 months, but routinely only after 6 or 8 months of therapy. Finally, FPHL is the slowest to respond to therapy, if it will at all, and it may take 12 to 18 months of therapy for an observable response., (Copyright © 2016. Published by Elsevier Ltd.)

Polycystic ovary syndrome (PCOS) affects 5-20% of women of reproductive age worldwide. The condition is characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology (PCOM) - with excessive androgen production by the ovaries being a key feature of PCOS. Metabolic dysfunction characterized by insulin resistance and compensatory hyperinsulinaemia is evident in the vast majority of affected individuals. PCOS increases the risk for type 2 diabetes mellitus, gestational diabetes and other pregnancy-related complications, venous thromboembolism, cerebrovascular and cardiovascular events and endometrial cancer. PCOS is a diagnosis of exclusion, based primarily on the presence of hyperandrogenism, ovulatory dysfunction and PCOM. Treatment should be tailored to the complaints and needs of the patient and involves targeting metabolic abnormalities through lifestyle changes, medication and potentially surgery for the prevention and management of excess weight, androgen suppression and/or blockade, endometrial protection, reproductive therapy and the detection and treatment of psychological features. This Primer summarizes the current state of knowledge regarding the epidemiology, mechanisms and pathophysiology, diagnosis, screening and prevention, management and future investigational directions of the disorder.

Polycystic ovary syndrome (PCOS) is a highly prevalent disorder effecting reproductive-aged women worldwide. This article addresses the evolution of the criteria used to diagnosis PCOS; reviews recent advances in the phenotypic approach, specifically in the context of the extended Rotterdam criteria; discusses limitations of the current criteria used to diagnosis, particularly when studying adolescents and women in the peri- and postmenopause; and describes significant strides made in understanding the epidemiology of PCOS. This review recognizes that although there is a high prevalence of PCOS, there is increased variability when using Rotterdam 2003 criteria, owing to limitations in population sampling and approaches used to define PCOS phenotypes. Last, we discuss the distribution of PCOS phenotypes, their morbidity, and the role that referral bias plays in the epidemiology of this syndrome., (Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)