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Rosenfield RL. The Search for the Causes of Common Hyperandrogenism, 1965 to Circa 2015. Endocr Rev 2024; 45:553-592. [PMID: 38457123 DOI: 10.1210/endrev/bnae007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 12/23/2023] [Accepted: 03/06/2024] [Indexed: 03/09/2024]
Abstract
From 1965 to 2015, immense strides were made into understanding the mechanisms underlying the common androgen excess disorders, premature adrenarche and polycystic ovary syndrome (PCOS). The author reviews the critical discoveries of this era from his perspective investigating these disorders, commencing with his early discoveries of the unique pattern of plasma androgens in premature adrenarche and the elevation of an index of the plasma free testosterone concentration in most hirsute women. The molecular genetic basis, though not the developmental biologic basis, for adrenarche is now known and 11-oxytestosterones shown to be major bioactive adrenal androgens. The evolution of the lines of research into the pathogenesis of PCOS is historically traced: research milestones are cited in the areas of neuroendocrinology, insulin resistance, hyperinsulinism, type 2 diabetes mellitus, folliculogenesis, androgen secretion, obesity, phenotyping, prenatal androgenization, epigenetics, and complex genetics. Large-scale genome-wide association studies led to the 2014 discovery of an unsuspected steroidogenic regulator DENND1A (differentially expressed in normal and neoplastic development). The splice variant DENND1A.V2 is constitutively overexpressed in PCOS theca cells in long-term culture and accounts for their PCOS-like phenotype. The genetics are complex, however: DENND1A intronic variant copy number is related to phenotype severity, and recent data indicate that rare variants in a DENND1A regulatory network and other genes are related to PCOS. Obesity exacerbates PCOS manifestations via insulin resistance and proinflammatory cytokine excess; excess adipose tissue also forms testosterone. Polycystic ovaries in 40 percent of apparently normal women lie on the PCOS functional spectrum. Much remains to be learned.
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Affiliation(s)
- Robert L Rosenfield
- Department of Pediatrics and Medicine, The University of Chicago, Chicago, IL 94109, USA
- Department of Pediatrics, The University of California, San Francisco, San Francisco, CA 94143, USA
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Melado L, Lawrenz B, Edades J, Kumar A, Fatemi H. A novel antimüllerian gene mutation in a woman with high antral follicle count and extremely low serum antimüllerian hormone levels. F S Rep 2024; 5:152-156. [PMID: 38983732 PMCID: PMC11228770 DOI: 10.1016/j.xfre.2024.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 01/30/2024] [Accepted: 01/30/2024] [Indexed: 07/11/2024] Open
Abstract
Objective To report a case with a distinct difference between the ovarian reserve parameters of antimüllerian hormone (AMH) levels, antral follicle count (AFC), and follicle-stimulating hormone levels caused by a novel homozygous missense variant in the exon 1 of the AMH gene [NM_000479.4:c259G>A, p.(Val87Met)]. Design Case report. Setting Tertiary referral in vitro fertilization clinic. Patients A 33-year-old woman, G4P4A0E0L4, with a BMI of 25.33 kg/m2, high AFC, and repeated extremely low systemic AMH levels, was detected and measured using multiple enzyme-linked immunosorbent assays. Interventions Antimüllerian hormone analysis with multiple assays, whole exome sequencing through next generation sequencing to diagnose the missense variant, and inhibin B measurement. Main Outcomes Measures Genetic counseling and two subsequent ovarian stimulations for successful fertility preservation. Results Detection of the [NM_000479.4:c259G>A, p.(Val87Met)] variant in the AMH gene. Retrieval and cryopreservation of four euploid blastocysts and 26 metaphase II oocytes. Conclusions AMH gene mutations can lead to the absence of systemic AMH levels and might be discordant to other ovarian reserve markers like AFC, follicle-stimulating hormone, and inhibin B, without affecting the ovarian response to ovarian stimulation. Clinicians should not rely exclusively on AMH levels for ovarian stimulation. When severely reduced AMH levels are found in patients with high AFC, AMH variants should be suspected, and fertility treatments should be tailored adequately.
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Affiliation(s)
- Laura Melado
- ART Fertility Clinics, Abu Dhabi, United Arab Emirates
| | - Barbara Lawrenz
- ART Fertility Clinics, Abu Dhabi, United Arab Emirates
- Reproductive Unit, UZ Gent., Gent, Belgium
| | | | - Ajay Kumar
- Ansh Labs LLC, Medical Center Blvd, Webster, Iowa
| | - Human Fatemi
- ART Fertility Clinics, Abu Dhabi, United Arab Emirates
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Marquez K, Hoyos LR. Serum levels of antimüllerian hormone: more than meets the eye. F S Rep 2024; 5:136-137. [PMID: 38983742 PMCID: PMC11228795 DOI: 10.1016/j.xfre.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024] Open
Affiliation(s)
- Kyara Marquez
- Department of Obstetrics and Gynecology, University of Miami/Jackson Health System, Miami, Florida
| | - Luis R Hoyos
- IVF Florida Reproductive Associates, Margate, Florida
- Department of Obstetrics and Gynecology, Florida International University, Herbert Wertheim College of Medicine, Miami, Florida
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Howard JA, Hok L, Cate RL, Sanford NJ, Hart KN, Leach EAE, Bruening AS, Pépin D, Donahoe PK, Thompson TB. Structural Basis of Non-Latent Signaling by the Anti-Müllerian Hormone Procomplex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.01.587627. [PMID: 38617313 PMCID: PMC11014609 DOI: 10.1101/2024.04.01.587627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Most TGFβ family ligands exist as procomplexes consisting of a prodomain noncovalently bound to a growth factor (GF); Whereas some prodomains confer latency, the Anti-Müllerian Hormone (AMH) prodomain maintains a remarkably high affinity for the GF yet remains active. Using single particle EM methods, we show the AMH prodomain consists of two subdomains: a vestigial TGFβ prodomain-like fold and a novel, helical bundle GF-binding domain, the result of an exon insertion 450 million years ago, that engages both receptor epitopes. When associated with the prodomain, the AMH GF is distorted into a strained, open conformation whose closure upon bivalent binding of AMHR2 displaces the prodomain through a conformational shift mechanism to allow for signaling.
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Affiliation(s)
- James A Howard
- Department of Pharmacology & Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
| | - Lucija Hok
- Department of Molecular & Cellular Biosciences, University of Cincinnati, Cincinnati, OH, United States
| | - Richard L Cate
- Department of Chemistry, Boston University, Boston, MA, United States
| | - Nathaniel J Sanford
- Department of Molecular & Cellular Biosciences, University of Cincinnati, Cincinnati, OH, United States
| | - Kaitlin N Hart
- Department of Pharmacology & Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
| | - Edmund AE Leach
- Department of Molecular & Cellular Biosciences, University of Cincinnati, Cincinnati, OH, United States
| | - Alena S Bruening
- Department of Molecular & Cellular Biosciences, University of Cincinnati, Cincinnati, OH, United States
| | - David Pépin
- Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Department of Surgery, Harvard Medical School, Boston, MA, United States
| | - Patricia K Donahoe
- Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Department of Surgery, Harvard Medical School, Boston, MA, United States
| | - Thomas B Thompson
- Department of Molecular & Cellular Biosciences, University of Cincinnati, Cincinnati, OH, United States
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Yildiz S, Moolhuijsen LME, Visser JA. The Role of Anti-Müllerian Hormone in Ovarian Function. Semin Reprod Med 2024; 42:15-24. [PMID: 38781987 DOI: 10.1055/s-0044-1786732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Anti-Müllerian hormone (AMH) is a member of the transforming growth factor β (TGFβ) superfamily, whose actions are restricted to the endocrine-reproductive system. Initially known for its role in male sex differentiation, AMH plays a role in the ovary, acting as a gatekeeper in folliculogenesis by regulating the rate of recruitment and growth of follicles. In the ovary, AMH is predominantly expressed by granulosa cells of preantral and antral follicles (i.e., post primordial follicle recruitment and prior to follicle-stimulating hormone (FSH) selection). AMH signals through a BMP-like signaling pathway in a manner distinct from other TGFβ family members. In this review, the latest insights in AMH processing, signaling, its regulation of spatial and temporal expression pattern, and functioning in folliculogenesis are summarized. In addition, effects of AMH variants on ovarian function are reviewed.
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Affiliation(s)
- Sena Yildiz
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Loes M E Moolhuijsen
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jenny A Visser
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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Abbott DH, Hutcherson BA, Dumesic DA. Anti-Müllerian Hormone: A Molecular Key to Unlocking Polycystic Ovary Syndrome? Semin Reprod Med 2024; 42:41-48. [PMID: 38908381 DOI: 10.1055/s-0044-1787525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/24/2024]
Abstract
Anti-Müllerian hormone (AMH) is an important component within androgen receptor (AR)-regulated pathways governing the hyperandrogenic origin of polycystic ovary syndrome (PCOS). In women with PCOS, granulosa cell AMH overexpression in developing ovarian follicles contributes to elevated circulating AMH levels beginning at birth and continuing in adolescent daughters of PCOS women. A 6 to 7% incidence among PCOS women of gene variants coding for AMH or its receptor, AMHR2, suggests genetic contributions to AMH-related pathogenesis. Discrete gestational AMH administration to pregnant mice induces hypergonadotropic hyperandrogenic, PCOS-like female offspring with high circulating AMH levels that persist over three generations, suggesting epigenetic contributions to PCOS through developmental programming. Moreover, adult-onset, selective hyperactivation of hypothalamic neurons expressing gonadotropin-releasing hormone (GnRH) induces hypergonadotropic hyperandrogenism and PCOS-like traits in female mice. Both gestational and adult AMH inductions of PCOS-like traits are prevented by GnRH antagonist coadministration, implicating luteinizing hormone-dependent ovarian theca cell testosterone (T) action, mediated through the AR in AMH-induced pathogenesis. Interestingly, gestational or peripubertal exogenous T or dihydrotestosterone induction of PCOS-like traits in female mice, rats, sheep, and monkeys fails to elicit ovarian AMH hypersecretion; thus, AMH excess per se may lead to a distinct pathogenic contribution to hyperandrogenic PCOS origins.
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Affiliation(s)
- David H Abbott
- Department of Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin
- Endocrinology and Reproductive Physiology Training Program, University of Wisconsin, Madison, Wisconsin
| | - Beverly A Hutcherson
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin
- Endocrinology and Reproductive Physiology Training Program, University of Wisconsin, Madison, Wisconsin
- Dean's Office, University of Wisconsin School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin
| | - Daniel A Dumesic
- Department of Obstetrics and Gynecology, University of California, Los Angeles, California
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Stocker WA, Howard JA, Maskey S, Luan H, Harrison SG, Hart KN, Hok L, Thompson TB, Walton KL, Harrison CA. Characterization of the molecular mechanisms that govern anti-Müllerian hormone synthesis and activity. FASEB J 2024; 38:e23377. [PMID: 38133902 PMCID: PMC10926428 DOI: 10.1096/fj.202301335rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 11/30/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
The roles of anti-Müllerian hormone (AMH) continue to expand, from its discovery as a critical factor in sex determination, through its identification as a regulator of ovarian folliculogenesis, its use in fertility clinics as a measure of ovarian reserve, and its emerging role in hypothalamic-pituitary function. In light of these actions, AMH is considered an attractive therapeutic target to address diverse reproductive needs, including fertility preservation. Here, we set out to characterize the molecular mechanisms that govern AMH synthesis and activity. First, we enhanced the processing of the AMH precursor to >90% by introducing more efficient proprotein convertase cleavage sites (RKKR or ISSRKKRSVSS [SCUT]). Importantly, enhanced processing corresponded with a dramatic increase in secreted AMH activity. Next, based on species differences across the AMH type II receptor-binding interface, we generated a series of human AMH variants and assessed bioactivity. AMHSCUT potency (EC50 4 ng/mL) was increased 5- or 10-fold by incorporating Gln484 Met/Leu535 Thr (EC50 0.8 ng/mL) or Gln484 Met/Gly533 Ser (EC50 0.4 ng/mL) mutations, respectively. Furthermore, the Gln484 Met/Leu535 Thr double mutant displayed enhanced efficacy, relative to AMHSCUT . Finally, we identified residues within the wrist pre-helix of AMH (Trp494 , Gln496 , Ser497 , and Asp498 ) that likely mediate type I receptor binding. Mutagenesis of these residues generated gain- (Trp494 Phe or Gln496 Leu) or loss- (Ser497 Ala) of function AMH variants. Surprisingly, combining activating type I and type II receptor mutations only led to modest additive increases in AMH potency/efficacy. Our study is the first to characterize AMH residues involved in type I receptor binding and suggests a step-wise receptor-complex assembly mechanism, in which enhancement in the affinity of the ligand for either receptor can increase AMH activity beyond the natural level.
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Affiliation(s)
- William A. Stocker
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - James A. Howard
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Shreya Maskey
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Haitong Luan
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Sophie G. Harrison
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Kaitlin N. Hart
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Lucija Hok
- Department of Molecular and Cellular Biosciences, University of Cincinnati, Cincinnati, Ohio, USA
| | - Thomas B. Thompson
- Department of Molecular and Cellular Biosciences, University of Cincinnati, Cincinnati, Ohio, USA
| | - Kelly L. Walton
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Craig A. Harrison
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
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