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Coutinho EA, Kauffman AS. The Role of the Brain in the Pathogenesis and Physiology of Polycystic Ovary Syndrome (PCOS). Med Sci (Basel) 2019; 7:E84. [PMID: 31382541 PMCID: PMC6722593 DOI: 10.3390/medsci7080084] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/25/2019] [Accepted: 07/30/2019] [Indexed: 12/20/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder, affecting at least 10% of women of reproductive age. PCOS is typically characterized by the presence of at least two of the three cardinal features of hyperandrogenemia (high circulating androgen levels), oligo- or anovulation, and cystic ovaries. Hyperandrogenemia increases the severity of the condition and is driven by increased luteinizing hormone (LH) pulse secretion from the pituitary. Indeed, PCOS women display both elevated mean LH levels, as well as an elevated frequency of LH pulsatile secretion. The abnormally high LH pulse frequency, reflective of a hyperactive gonadotropin-releasing hormone (GnRH) neural circuit, suggests a neuroendocrine basis to either the etiology or phenotype of PCOS. Several studies in preclinical animal models of PCOS have demonstrated alterations in GnRH neurons and their upstream afferent neuronal circuits. Some rodent PCOS models have demonstrated an increase in GnRH neuron activity that correlates with an increase in stimulatory GABAergic innervation and postsynaptic currents onto GnRH neurons. Additional studies have identified robust increases in hypothalamic levels of kisspeptin, another potent stimulator of GnRH neurons. This review outlines the different brain and neuroendocrine changes in the reproductive axis observed in PCOS animal models, discusses how they might contribute to either the etiology or adult phenotype of PCOS, and considers parallel findings in PCOS women.
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Affiliation(s)
- Eulalia A Coutinho
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Alexander S Kauffman
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
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Lippincott MF, Chan YM, Delaney A, Rivera-Morales D, Butler JP, Seminara SB. Kisspeptin Responsiveness Signals Emergence of Reproductive Endocrine Activity: Implications for Human Puberty. J Clin Endocrinol Metab 2016; 101:3061-9. [PMID: 27214398 PMCID: PMC4971332 DOI: 10.1210/jc.2016-1545] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Some patients with idiopathic hypogonadotropic hypogonadism (IHH) undergo spontaneous activation of their hypothalamic-pituitary-gonadal axis resulting in normalization of steroidogenesis and/or gametogenesis, a phenomenon termed reversal. OBJECTIVE To assess the responsiveness of the GnRH neuronal network to exogenous kisspeptin administration in IHH patients who have undergone reversal. PARTICIPANTS Six men with congenital IHH and evidence for reversal. INTERVENTION Subjects underwent q10 min blood sampling to measure GnRH-induced LH secretion at baseline and in response to iv boluses of kisspeptin (0.24-2.4 nmol/kg) and GnRH (75 ng/kg). RESULTS Individuals with sustained reversal of their hypogonadotropism (spontaneous LH pulses) responded to exogenous kisspeptin with a GnRH-induced LH pulse. Individuals who had reversal but then subsequently suffered relapse of their IHH (loss of spontaneous LH pulsatility) did not respond to kisspeptin. CONCLUSIONS The ability of kisspeptin to stimulate a GnRH-induced LH pulse correlates with the presence of endogenous LH pulses. These data suggest that reversal of hypogonadotropism, and by extension sexual maturation, may be due to the acquisition of kisspeptin responsiveness.
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Affiliation(s)
- Margaret F Lippincott
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit (M.F.L., Y.-M.C., D.R.-M., S.B.S.), Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114; Division of Endocrinology (Y.-M.C.), Department of Medicine, Boston Children's Hospital, and Division of Sleep Medicine (J.P.B.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Unit on Genetics of Puberty and Reproduction (A.D.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892
| | - Yee-Ming Chan
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit (M.F.L., Y.-M.C., D.R.-M., S.B.S.), Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114; Division of Endocrinology (Y.-M.C.), Department of Medicine, Boston Children's Hospital, and Division of Sleep Medicine (J.P.B.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Unit on Genetics of Puberty and Reproduction (A.D.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892
| | - Angela Delaney
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit (M.F.L., Y.-M.C., D.R.-M., S.B.S.), Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114; Division of Endocrinology (Y.-M.C.), Department of Medicine, Boston Children's Hospital, and Division of Sleep Medicine (J.P.B.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Unit on Genetics of Puberty and Reproduction (A.D.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892
| | - Dianali Rivera-Morales
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit (M.F.L., Y.-M.C., D.R.-M., S.B.S.), Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114; Division of Endocrinology (Y.-M.C.), Department of Medicine, Boston Children's Hospital, and Division of Sleep Medicine (J.P.B.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Unit on Genetics of Puberty and Reproduction (A.D.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892
| | - James P Butler
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit (M.F.L., Y.-M.C., D.R.-M., S.B.S.), Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114; Division of Endocrinology (Y.-M.C.), Department of Medicine, Boston Children's Hospital, and Division of Sleep Medicine (J.P.B.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Unit on Genetics of Puberty and Reproduction (A.D.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892
| | - Stephanie B Seminara
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit (M.F.L., Y.-M.C., D.R.-M., S.B.S.), Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114; Division of Endocrinology (Y.-M.C.), Department of Medicine, Boston Children's Hospital, and Division of Sleep Medicine (J.P.B.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Unit on Genetics of Puberty and Reproduction (A.D.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland 20892
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Siegel RA. Stimuli sensitive polymers and self regulated drug delivery systems: a very partial review. J Control Release 2014; 190:337-51. [PMID: 24984012 PMCID: PMC4142101 DOI: 10.1016/j.jconrel.2014.06.035] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Revised: 06/18/2014] [Accepted: 06/21/2014] [Indexed: 10/25/2022]
Abstract
Since the early days of the Journal of Controlled Release, there has been considerable interest in materials that can release drug on an "on-demand" basis. So called "stimuli-responsive" and "intelligent" systems have been designed to deliver drug at various times or at various sites in the body, according to a stimulus that is either endogenous or externally applied. In the past three decades, research along these lines has taken numerous directions, and each new generation of investigators has discovered new physicochemical principles and chemical schemes by which the release properties of materials can be altered. No single review could possibly do justice to all of these approaches. In this article, some general observations are made, and a partial history of the field is presented. Both open loop and closed loop systems are discussed. Special emphasis is placed on stimuli-responsive hydrogels, and on systems that can respond repeatedly. It is argued that the most success at present and in the foreseeable future is with systems in which biosensing and actuation (i.e. drug delivery) are separated, with a human and/or cybernetic operator linking the two.
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Affiliation(s)
- Ronald A Siegel
- Department of Pharmaceutics, University of Minnesota, Minneapolis, MN 55455 USA; Department Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455 USA.
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Chan YM. Effects of kisspeptin on hormone secretion in humans. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 784:89-112. [PMID: 23550003 DOI: 10.1007/978-1-4614-6199-9_5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Studies of the actions of kisspeptin in human subjects have examined the effects of different kisspeptin isoforms, doses, and routes of administration on LH secretion, a surrogate measure of GnRH release. These studies, in addition to detailing how these different variables affect LH secretion in response to kisspeptin, have produced new insights into kisspeptin physiology: (1) Brief exposure to kisspeptin results in sustained GnRH release lasting ~17 min in men. (2) Women in different phases of the menstrual cycle have differences in their response to kisspeptin, suggesting that endogenous kisspeptin secretion and GnRH neuronal responsiveness vary in response to the changing sex-steroid environment across the menstrual cycle. (3) Kisspeptin resets the GnRH pulse generator in men, but does not appear to do so in women. (4) Continuous exposure to kisspeptin results in desensitization to kisspeptin, and thus kisspeptin has the potential to either stimulate or suppress reproductive endocrine activity depending on the mode of administration. These findings pave the way for future studies using kisspeptin as a physiologic, diagnostic, and therapeutic tool in both healthy adults and in patients with reproductive disorders.
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Affiliation(s)
- Yee-Ming Chan
- Department of Medicine, Boston Children's Hospital, Boston, MA, USA.
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Chan YM, Butler JP, Sidhoum VF, Pinnell NE, Seminara SB. Kisspeptin administration to women: a window into endogenous kisspeptin secretion and GnRH responsiveness across the menstrual cycle. J Clin Endocrinol Metab 2012; 97:E1458-67. [PMID: 22577171 PMCID: PMC3410261 DOI: 10.1210/jc.2012-1282] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Kisspeptin is the most powerful known stimulus of GnRH-induced LH secretion across mammalian species. However, the effects of kisspeptin are just being explored, and the dynamics of kisspeptin responsiveness across the menstrual cycle are incompletely understood. OBJECTIVE The objective of the study was to characterize the effects of kisspeptin on GnRH secretion in healthy women in different phases of the menstrual cycle. PARTICIPANTS AND INTERVENTION Ten women in the early follicular phase, three women in the late follicular (preovulatory) phase, and 14 women in the midluteal phase received a bolus of kisspeptin 112-121 0.24 nmol/kg iv. An additional four women in the early to midfollicular phase received kisspeptin 112-121 0.72 nmol/kg iv. RESULTS The response to kisspeptin varied depending on the phase of the menstrual cycle. LH pulses were observed immediately after kisspeptin administration in all luteal and preovulatory women. However, only half the women in the early follicular phase had unambiguous kisspeptin responses. Increasing the kisspeptin dose did not increase the LH response in early to midfollicular phase women. Kisspeptin did not appear to reset the GnRH pulse generator in women as it does in men. CONCLUSIONS Differences in responses to exogenous kisspeptin across the menstrual cycle suggest that kisspeptin tone is higher in the early follicular phase compared with other cycle phases. The mechanisms that determine the timing of GnRH pulse generation in men and women appear to be distinct.
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Affiliation(s)
- Yee-Ming Chan
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
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Chan YM, Butler JP, Pinnell NE, Pralong FP, Crowley WF, Ren C, Chan KK, Seminara SB. Kisspeptin resets the hypothalamic GnRH clock in men. J Clin Endocrinol Metab 2011; 96:E908-15. [PMID: 21470997 PMCID: PMC3100758 DOI: 10.1210/jc.2010-3046] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Reproduction in all mammals is controlled by a hypothalamic clock that produces periodic secretory pulses of GnRH, but how the timing of these pulses is determined is poorly understood. The neuropeptide kisspeptin potently and selectively stimulates the secretion of GnRH. Although this property of kisspeptin is well described, the effects of kisspeptin on endogenous GnRH pulse generation remain largely unexplored. OBJECTIVE The objective of the study was to detail the effects of kisspeptin on GnRH secretion, as reflected by LH secretion, in men. PARTICIPANTS Thirteen healthy adult men participated in the study. INTERVENTION The intervention was the administration of a single iv bolus of the C-terminal decapeptide of kisspeptin (amino acids 112-121 of the parent protein). RESULTS Kisspeptin induced an immediate LH pulse, regardless of the timing of the previous endogenous pulse. The kisspeptin-induced pulses were on average larger than endogenous pulses (amplitude 5.0 ± 1.0 vs. 2.1 ± 0.3 mIU/ml, P = 0.02). Comparison of the morphology of kisspeptin-induced LH pulses in healthy men with that of GnRH-induced LH pulses in men with isolated GnRH deficiency suggests that a single i.v. bolus of kisspeptin triggered sustained GnRH release lasting approximately 17 min. Furthermore, kisspeptin reset the GnRH pulse generator, as it not only induced an immediate LH pulse but also delayed the next endogenous pulse by an interval approximating the normal interpulse interval. CONCLUSIONS As the first known agent capable of resetting the hypothalamic GnRH pulse generator, kisspeptin can be used as a physiological tool for studying GnRH pulse generation and opens a door to understanding the mechanisms of biological clocks in general.
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Affiliation(s)
- Yee-Ming Chan
- Harvard Reproductive Sciences Center and Reproductive Endocrine Unit, Department of Medicine, Massachusetts General Hospital, 55 Fruit Street, BHX 5, Boston, Massachusetts 02114, USA.
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Chhabra S, McCartney CR, Yoo RY, Eagleson CA, Chang RJ, Marshall JC. Progesterone inhibition of the hypothalamic gonadotropin-releasing hormone pulse generator: evidence for varied effects in hyperandrogenemic adolescent girls. J Clin Endocrinol Metab 2005; 90:2810-5. [PMID: 15728200 DOI: 10.1210/jc.2004-2359] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Compared with normal women, adults with polycystic ovarian syndrome (PCOS) require higher progesterone (P) concentrations to inhibit GnRH (LH) pulse frequency, which contributes to persistently rapid GnRH pulses and elevated LH levels in PCOS. To explore the origin of this abnormality, we assessed hypothalamic sensitivity to P feedback in nine normal controls and 11 hyperandrogenemic (HA) adolescents. Subjects first underwent frequent blood sampling for 11 h to assess baseline LH pulse frequency. Thereafter, oral estradiol and micronized P were given for 7 d to achieve mean estradiol and P levels of 143 +/- 16 pg/ml (524 +/- 60 pmol/liter) and 7.8 +/- 0.7 ng/ml (24.9 +/- 2.3 nmol/liter), respectively. LH pulse frequency was then reassessed. On d 7, the slope of the percent reduction of LH pulses per 11 h as a function of the d 7 P concentration was less in the HA group compared with controls (P = 0.02) despite similar P levels. LH pulse frequency was suppressed in all NC (mean, 7.0 to 3.4 pulses/11 h), but was unchanged in six of the HA girls (mean, 8.3 to 7.5 pulses/11 h). In contrast, in the other five HA adolescents, P induced similar slowing of LH pulses to that seen in NC (mean, 10.0 to 5.0 pulses/11 h). Baseline free testosterone levels were similar in both HA groups; the only observed difference between these HA groups is that the P-suppressible subjects were all of Hispanic descent. These data suggest that hyperandrogenemia during adolescence is variably associated with decreased sensitivity to P, which may have a partially genetic basis.
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Affiliation(s)
- Sandhya Chhabra
- Center for Research in Reproduction, Division of Endocrinology, Department of Internal Medicine, Box 800391, University of Virginia Health System, Charlottesville, Virginia 22908, USA.
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