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West S, Garza V, Cardoso R. Puberty in beef heifers: effects of prenatal and postnatal nutrition on the development of the neuroendocrine axis. Anim Reprod 2024; 21:e20240048. [PMID: 39176002 PMCID: PMC11340802 DOI: 10.1590/1984-3143-ar2024-0048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 05/29/2024] [Indexed: 08/24/2024] Open
Abstract
Reproductive maturation is a complex physiological process controlled by the neuroendocrine system and is characterized by an increase in gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) pulsatile secretion. Nutrition during early development is a key factor regulating puberty onset, which is defined as first ovulation in females. In heifers, nutrient restriction after weaning delays puberty, whereas elevated levels of nutrition and energy reserves advance reproductive maturation. Recent studies in cattle and other animal models have shown that the dam's nutrition during gestation can also program the neuroendocrine system in the developing fetus and has the potential to alter timing of puberty in the offspring. Among the metabolic signals that modulate brain development and control timing of puberty is leptin, a hormone produced primarily by adipocytes that communicates energy status to the brain. Leptin acts within the arcuate nucleus of the hypothalamus to regulate GnRH secretion via an upstream network of neurons that includes neurons that express neuropeptide Y (NPY), an orexigenic peptide with inhibitory effects on GnRH secretion, and alpha melanocyte-stimulating hormone (αMSH), an anorexigenic peptide with excitatory effects on GnRH neurons. Another important population of neurons are KNDy neurons, neurons in the arcuate nucleus that co-express the neuropeptides kisspeptin, neurokinin B, and dynorphin and have strong stimulatory effects on GnRH secretion. Our studies in beef heifers indicate that increased nutrition between 4 to 8 months of age advances puberty by diminishing NPY inhibitory tone and by increasing excitatory inputs of αMSH and kisspeptin, which collectively lead to increased GnRH/LH pulsatility. Our ongoing studies indicate that different planes of nutrition during gestation can alter maternal leptin concentrations and promote changes in the fetal brain. Nonetheless, at least in Bos indicus-influenced heifers, deficits programmed prenatally can be overcome by adequate postnatal nutrition without negatively impacting age at puberty or subsequent fertility.
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Affiliation(s)
- Sarah West
- Department of Animal Science, Texas A&M University, College Station, TX, USA
| | - Viviana Garza
- Department of Animal Science, Texas A&M University, College Station, TX, USA
| | - Rodolfo Cardoso
- Department of Animal Science, Texas A&M University, College Station, TX, USA
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2
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Gurule SC, Sustaita-Monroe JF, King LN, Landers RS, Garza V, West SM, Bynum SE, Perry L, Padmanabhan V, Cardoso RC. Reproductive neuroendocrine defects programmed by prenatal testosterone treatment between gestational days 60-90 are amplified by postnatal obesity in sheep. Front Physiol 2024; 15:1436954. [PMID: 39156826 PMCID: PMC11327049 DOI: 10.3389/fphys.2024.1436954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 07/01/2024] [Indexed: 08/20/2024] Open
Abstract
Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility in women of reproductive age, and obesity can increase the severity and development of the PCOS phenotype. Prenatal testosterone (T) treatment between gestational days 30-90 advanced puberty and disrupted the reproductive and metabolic phenotype in female sheep, recapitulating attributes of women with PCOS, with postnatal obesity amplifying its severity. On the other hand, prenatal T treatment from gestational days 60-90 led to a much milder phenotype. We hypothesized that reproductive neuroendocrine defects programmed by prenatal T treatment between gestational days 60-90 are amplified by postnatal obesity in sheep. Suffolk ewes received T propionate (T; 100 mg) or corn oil (C; vehicle) twice weekly from gestational days 60-90. At 5 months of age, T lambs were assigned to either a maintenance (100% of NRC requirements) or overfed (130% NRC) diet and C lambs were fed the maintenance diet. We compared the timing of puberty (n = 15/group) determined by twice weekly measurement of progesterone concentrations, estradiol positive feedback responsiveness (n = 8/group) determined by assessing LH secretion in response to exogenous estradiol, periovulatory LH dynamics during the second breeding season (n = 8/group) following synchronization with two injections of PGF2α, and progesterone negative feedback (n = 8/group) determined by characterizing LH pulses during the mid-luteal phase between C, T-maintenance and T-overfed groups. Our findings indicate that postnatal obesity: 1) exacerbated reproductive defects and further deteriorated reproductive cyclicity during the second breeding season (adulthood); 2) did not amplify the impairment in estradiol positive feedback in delaying the timing and amplitude of the LH surge, although it reduced the total amount of LH secreted during the preovulatory LH surge; 3) amplified the reduced responsiveness to progesterone negative feedback manifested as an increase in LH pulse amplitude and peak. These observations, in addition to supporting our previous findings that prenatal T treatment results in reproductive neuroendocrine dysfunction and periovulatory disruptions, provide evidence that these neuroendocrine defects programmed between gestational days 60-90 are amplified by postnatal obesity in female sheep.
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Affiliation(s)
- S. C. Gurule
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - J. F. Sustaita-Monroe
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - L. N. King
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - R. S. Landers
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - V. Garza
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - S. M. West
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - S. E. Bynum
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - L. Perry
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - V. Padmanabhan
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - R. C. Cardoso
- Department of Animal Science, Texas A&M University, College Station, TX, United States
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Thorson JF, Prezotto LD. Malnutrition alters protein expression of KNDy neuropeptides in the arcuate nucleus of mature ewes. Front Physiol 2024; 15:1372944. [PMID: 38911326 PMCID: PMC11190783 DOI: 10.3389/fphys.2024.1372944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 05/15/2024] [Indexed: 06/25/2024] Open
Abstract
The neuropeptides kisspeptin, neurokinin B, and dynorphin A are imperative for the pulsatile secretion of gonadotropin-releasing hormone and luteinizing hormone to ultimately regulate reproductive cyclicity. A population of neurons co-expressing these neuropeptides, KNDy neurons, within the arcuate nucleus of the hypothalamus (ARC) are positioned to integrate energy status from afferent neuronal and glial cells. We hypothesized that KNDy-expressing neurons in the ARC of mature ewes are influenced by energy balance. To test this hypothesis, ovary-intact, mature ewes were fed to lose, maintain, or gain body weight and hypothalamic tissue harvested during the luteal phase of the estrous cycle. Fluorescent, multiplex immunohistochemistry with direct antibody conjugation was employed to identify and quantify neurons expressing a single neuropeptide, as well as for the first time report co-expression of kisspeptin, neurokinin B, and dynorphin A protein in the ARC. Previous reports using this population of ewes demonstrated that concentrations of insulin and leptin differed between ewes fed to achieve different body weights and that ewes fed to gain body weight had increased concentrations of progesterone. Moreover, within this population of ewes tanycyte density and cellular penetration into the ARC was increased in ewes fed to gain body weight. Within the current report we have revealed that the number of neurons in the ARC expressing kisspeptin, neurokinin B, and dynorphin A protein was increased in ewes fed to gain body weight. Moreover, the number of KNDy neurons in the ARC expressing all three neuropeptides within a single neuron was decreased in ewes fed to lose body weight and increased in ewes fed to gain body weight when compared to ewes fed to maintain body weight. The cumulative findings of this experimental model suggest that expression of kisspeptin, neurokinin B, and dynorphin A protein in the ARC during the luteal phase of the estrous cycle are influenced by energy balance-induced alterations in circulating concentrations of progesterone that drive changes in morphology and density of tanycytes to ultimately regulate central perception of global energy status. Moreover, these results demonstrate that changes in KNDy neurons within the ARC occur as an adaptation to energy balance, potentially regulated divergently by metabolic milieu via proopiomelanocortin afferents.
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Affiliation(s)
- Jennifer F. Thorson
- Nutrition, Growth and Physiology Research Unit, U.S. Meat Animal Research Center, Agricultural Research Service, United States Department of Agriculture, Clay Center, United States
| | - Ligia D. Prezotto
- Physiology Laboratory, Department of Animal Science, University of Nebraska-Lincoln, Lincoln, United States
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Męczekalski B, Niwczyk O, Battipaglia C, Troia L, Kostrzak A, Bala G, Maciejewska-Jeske M, Genazzani AD, Luisi S. Neuroendocrine disturbances in women with functional hypothalamic amenorrhea: an update and future directions. Endocrine 2024; 84:769-785. [PMID: 38062345 PMCID: PMC11208264 DOI: 10.1007/s12020-023-03619-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 11/17/2023] [Indexed: 01/31/2024]
Abstract
Functional hypothalamic amenorrhea (FHA) is one of the most common causes of both primary and secondary amenorrhea in women of reproductive age. It is characterized by chronic anovulation and the absence of menses that appear as a result of stressors such as eating disorders, excessive exercise, or psychological distress. FHA is presumed to be a functional disruption in the pulsatile secretion of hypothalamic gonadotropin-releasing hormone, which in turn impairs the release of gonadotropin. Hypoestrogenism is observed due to the absence of ovarian follicle recruitment. Numerous neurotransmitters have been identified which play an important role in the regulation of the hypothalamic-pituitary-ovarian axis and of which the impairment would contribute to developing FHA. In this review we summarize the most recent advances in the identification of contributing neuroendocrine disturbances and relevant contributors to the development of FHA.
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Affiliation(s)
- Błażej Męczekalski
- Department of Gynecological Endocrinology, Poznan University of Medical Sciences, Poznan, Poland.
| | - Olga Niwczyk
- Department of Gynecological Endocrinology, Poznan University of Medical Sciences, Poznan, Poland
| | - Christian Battipaglia
- Gynecological Endocrinology Center, Department of Obstetrics and Gynecology, University of Modena and Reggio Emilia, Modena, Italy
| | - Libera Troia
- Department of Gynecology and Obstetrics, Maggiore della Carità Hospital, University of Eastern Piedmont, Novara, Italy
| | - Anna Kostrzak
- Department of Gynecological Endocrinology, Poznan University of Medical Sciences, Poznan, Poland
| | - Gregory Bala
- UCD School of Medicine University College Dublin, D04 V1W8, Dublin, Ireland
| | | | - Alessandro D Genazzani
- Gynecological Endocrinology Center, Department of Obstetrics and Gynecology, University of Modena and Reggio Emilia, Modena, Italy
| | - Stefano Luisi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
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5
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Wu W, Ren J, Wang J, Wang J, Yu D, Zhang Y, Zeng F, Huang B. Metalloestrogens exposure and risk of gestational diabetes mellitus: Evidence emerging from the systematic review and meta-analysis. ENVIRONMENTAL RESEARCH 2024; 248:118321. [PMID: 38307186 DOI: 10.1016/j.envres.2024.118321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/04/2024] [Accepted: 01/25/2024] [Indexed: 02/04/2024]
Abstract
BACKGROUND Metalloestrogens are metals and metalloid elements with estrogenic activity found everywhere. Their impact on human health is becoming more apparent as human activities increase. OBJECTIVE Our aim is to conduct a comprehensive systematic review and meta-analysis of observational studies exploring the correlation between metalloestrogens (specifically As, Sb, Cr, Cd, Cu, Se, Hg) and Gestational Diabetes Mellitus (GDM). METHODS PubMed, Web of Science, and Embase were searched to examine the link between metalloestrogens (As, Sb, Cr, Cd, Cu, Se, and Hg) and GDM until December 2023. Risk estimates were derived using random effects models. Subgroup analyses were conducted based on study countries, exposure sample, exposure assessment method, and detection methods. Sensitivity analyses and adjustments for publication bias were carried out to assess the strength of the findings. RESULTS Out of the 389 articles identified initially, 350 met our criteria and 33 were included in the meta-analysis, involving 141,175 subjects (9450 cases, 131,725 controls). Arsenic, antimony, and copper exposure exhibited a potential increase in GDM risk to some extent (As: OR = 1.28, 95 % CI [1.08, 1.52]; Sb: OR = 1.73, 95 % CI [1.13, 2.65]; Cu: OR = 1.29, 95 % CI [1.02, 1.63]), although there is a high degree of heterogeneity (As: Q = 52.93, p < 0.05, I2 = 64.1 %; Sb: Q = 31.40, p < 0.05, I2 = 80.9 %; Cu: Q = 21.14, p < 0.05, I2 = 71.6 %). Conversely, selenium, cadmium, chromium, and mercury exposure did not exhibit any association with the risk of GDM in our study. DISCUSSION Our research indicates that the existence of harmful metalloestrogens in the surroundings has a notable effect on the likelihood of GDM. Hence, we stress the significance of environmental elements in the development of GDM and the pressing need for relevant policies and measures.
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Affiliation(s)
- Wanxin Wu
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, MOE Key Laboratory of Population Health Across Life Cycle, NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Junjie Ren
- Department of Medical Psychology, School of Mental Health and Psychological Science, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Juan Wang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, MOE Key Laboratory of Population Health Across Life Cycle, NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Jiamei Wang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, MOE Key Laboratory of Population Health Across Life Cycle, NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Deshui Yu
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, MOE Key Laboratory of Population Health Across Life Cycle, NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Yan Zhang
- School of Biology and Food Engineering, Hefei Normal University, Hefei, 230092, Anhui, China.
| | - Fa Zeng
- Shenzhen Longhua Maternity and Child Healthcare Hospital, Shenzhen, 518109, Guangdong, China.
| | - Binbin Huang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, MOE Key Laboratory of Population Health Across Life Cycle, NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, 230032, Anhui, China.
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6
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Salmeri N, Viganò P, Cavoretto P, Marci R, Candiani M. The kisspeptin system in and beyond reproduction: exploring intricate pathways and potential links between endometriosis and polycystic ovary syndrome. Rev Endocr Metab Disord 2024; 25:239-257. [PMID: 37505370 DOI: 10.1007/s11154-023-09826-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/18/2023] [Indexed: 07/29/2023]
Abstract
Endometriosis and polycystic ovary syndrome (PCOS) are two common female reproductive disorders with a significant impact on the health and quality of life of women affected. A novel hypothesis by evolutionary biologists suggested that these two diseases are inversely related to one another, representing a pair of diametrical diseases in terms of opposite alterations in reproductive physiological processes but also contrasting phenotypic traits. However, to fully explain the phenotypic features observed in women with these conditions, we need to establish a potential nexus system between the reproductive system and general biological functions. The recent discovery of kisspeptin as pivotal mediator of internal and external inputs on the hypothalamic-pituitary-gonadal axis has led to a new understanding of the neuroendocrine upstream regulation of the human reproductive system. In this review, we summarize the current knowledge on the physiological roles of kisspeptin in human reproduction, as well as its involvement in complex biological functions such as metabolism, inflammation and pain sensitivity. Importantly, these functions are known to be dysregulated in both PCOS and endometriosis. Within the evolving scientific field of "kisspeptinology", we critically discuss the clinical relevance of these discoveries and their potential translational applications in endometriosis and PCOS. By exploring the possibilities of manipulating this complex signaling system, we aim to pave the way for novel targeted therapies in these reproductive diseases.
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Affiliation(s)
- Noemi Salmeri
- Gynecology and Obstetrics Unit, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Paola Viganò
- Infertility Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via M. Fanti 6, 20122, Milan, Italy.
| | - Paolo Cavoretto
- Gynecology and Obstetrics Unit, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Roberto Marci
- Gynecology & Obstetrics, University of Ferrara, 44121, Ferrara, Italy
| | - Massimo Candiani
- Gynecology and Obstetrics Unit, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
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7
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Aerts EG, Griesgraber MJ, Shuping SL, Bowdridge EC, Hardy SL, Goodman RL, Nestor CC, Hileman SM. The effect of NK3-Saporin injection within the arcuate nucleus on puberty, the LH surge, and the response to Senktide in female sheep†. Biol Reprod 2024; 110:275-287. [PMID: 37930247 DOI: 10.1093/biolre/ioad147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/09/2023] [Accepted: 10/24/2023] [Indexed: 11/07/2023] Open
Abstract
The timing of puberty onset is reliant on increased gonadotropin-releasing hormone (GnRH). This elicits a corresponding increase in luteinizing hormone (LH) due to a lessening of sensitivity to the inhibitory actions of estradiol (E2). The mechanisms underlying the increase in GnRH release likely involve a subset of neurons within the arcuate (ARC) nucleus of the hypothalamus that contain kisspeptin, neurokinin B (NKB), and dynorphin (KNDy neurons). We aimed to determine if KNDy neurons in female sheep are critical for: timely puberty onset; the LH surge; and the response to an intravenous injection of the neurokinin-3 receptor (NK3R) agonist, senktide. Prepubertal ewes received injections aimed at the ARC containing blank-saporin (control, n = 5) or NK3-saporin (NK3-SAP, n = 6) to ablate neurons expressing NK3R. Blood samples taken 3/week for 65 days following surgery were assessed for progesterone to determine onset of puberty. Control ewes exhibited onset of puberty at 33.2 ± 3.9 days post sampling initiation, whereas 5/6 NK3-SAP treated ewes didn't display an increase in progesterone. After an artificial LH surge protocol, surge amplitude was lower in NK3-SAP ewes. Finally, ewes were treated with senktide to determine if an LH response was elicited. LH pulses were evident in both groups in the absence of injections, but the response to senktide vs saline was similar between groups. These results show that KNDy cells are necessary for timely puberty onset and for full expresson of the LH surge. The occurrence of LH pulses in NK3-SAP treated ewes may indicate a recovery from an apulsatile state.
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Affiliation(s)
- Eliana G Aerts
- Department of Physiology, Pharmacology and Toxicology, Morgantown, WV 26506, USA
| | - Max J Griesgraber
- Department of Physiology, Pharmacology and Toxicology, Morgantown, WV 26506, USA
| | - Sydney L Shuping
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695, USA
| | | | - Steven L Hardy
- Department of Physiology, Pharmacology and Toxicology, Morgantown, WV 26506, USA
| | - Robert L Goodman
- Department of Physiology, Pharmacology and Toxicology, Morgantown, WV 26506, USA
- Department of Neuroscience, West Virginia University, Morgantown, WV 26506, USA
| | - Casey C Nestor
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695, USA
| | - Stanley M Hileman
- Department of Physiology, Pharmacology and Toxicology, Morgantown, WV 26506, USA
- Department of Neuroscience, West Virginia University, Morgantown, WV 26506, USA
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Patel B, Koysombat K, Mills EG, Tsoutsouki J, Comninos AN, Abbara A, Dhillo WS. The Emerging Therapeutic Potential of Kisspeptin and Neurokinin B. Endocr Rev 2024; 45:30-68. [PMID: 37467734 PMCID: PMC10765167 DOI: 10.1210/endrev/bnad023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 06/13/2023] [Accepted: 07/11/2023] [Indexed: 07/21/2023]
Abstract
Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and pulsatile GnRH secretion. Their critical role in reproductive health was first identified after inactivating variants in genes encoding for KP or NKB signaling were shown to result in congenital hypogonadotropic hypogonadism and a failure of pubertal development. Over the past 2 decades since their discovery, a wealth of evidence from both basic and translational research has laid the foundation for potential therapeutic applications. Beyond KP's function in the hypothalamus, it is also expressed in the placenta, liver, pancreas, adipose tissue, bone, and limbic regions, giving rise to several avenues of research for use in the diagnosis and treatment of pregnancy, metabolic, liver, bone, and behavioral disorders. The role played by NKB in stimulating the hypothalamic thermoregulatory center to mediate menopausal hot flashes has led to the development of medications that antagonize its action as a novel nonsteroidal therapeutic agent for this indication. Furthermore, the ability of NKB antagonism to partially suppress (but not abolish) the reproductive endocrine axis has supported its potential use for the treatment of various reproductive disorders including polycystic ovary syndrome, uterine fibroids, and endometriosis. This review will provide a comprehensive up-to-date overview of the preclinical and clinical data that have paved the way for the development of diagnostic and therapeutic applications of KP and NKB.
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Affiliation(s)
- Bijal Patel
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
| | - Kanyada Koysombat
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, 72 Du Cane Rd, London, W12 0HS, UK
| | - Edouard G Mills
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, 72 Du Cane Rd, London, W12 0HS, UK
| | - Jovanna Tsoutsouki
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
| | - Alexander N Comninos
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, 72 Du Cane Rd, London, W12 0HS, UK
| | - Ali Abbara
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, 72 Du Cane Rd, London, W12 0HS, UK
| | - Waljit S Dhillo
- Section of Investigative Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College School of Medicine, Imperial College London, London, W12 0NN, UK
- Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, 72 Du Cane Rd, London, W12 0HS, UK
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Panda SP, Kesharwani A, Singh GD, Prasanth D, Vatchavai BR, Kumari PVK, Panda SK, Mallick SP. Impose of KNDy/GnRH neural circuit in PCOS, ageing, cancer and Alzheimer's disease: StAR actions in prevention of neuroendocrine dysfunction. Ageing Res Rev 2023; 92:102086. [PMID: 37821047 DOI: 10.1016/j.arr.2023.102086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/06/2023] [Accepted: 10/08/2023] [Indexed: 10/13/2023]
Abstract
The Kisspeptin1 (KISS1)/neurokinin B (NKB)/Dynorphin (Dyn) [KNDy] neurons in the hypothalamus regulate the reproduction stage in human beings and rodents. KNDy neurons co-expressed all KISS1, NKB, and Dyn peptides, and hence commonly regarded as KISS1 neurons. KNDy neurons contribute to the "GnRH pulse generator" and are implicated in the regulation of pulsatile GnRH release. The estradiol (E2)-estrogen receptor (ER) interactions over GnRH neurons in the hypothalamus cause nitric oxide (NO) discharge, in addition to presynaptic GABA and glutamate discharge from respective neurons. The released GABA and glutamate facilitate the activity of GnRH neurons via GABAA-R and AMPA/kainate-R. The KISS1 stimulates MAPK/ERK1/2 signaling and cause the release of Ca2+ from intracellular store, which contribute to neuroendocrine function, increase apoptosis and decrease cell proliferation and metastasis. The ageing in women deteriorates KISS1/KISS1R interaction in the hypothalamus which causes lower levels of GnRH. Because examining the human brain is so challenging, decades of clinical research have failed to find the causes of KNDy/GnRH dysfunction. The KISS1/KISS1R interactions in the brain have a neuroprotective effect against Alzheimer's disease (AD). These findings modulate the pathophysiological role of the KNDy/GnRH neural network in polycystic ovarian syndrome (PCOS) associated with ageing and, its protective role in cancer and AD. This review concludes with protecting effect of the steroid-derived acute regulatory enzyme (StAR) against neurotoxicity in the hippocampus, and hypothalamus, and these measures are fundamental for delaying ageing with PCOS. StAR could serve as novel diagnostic marker and therapeutic target for the most prevalent hormone-sensitive breast cancers (BCs).
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Affiliation(s)
- Siva Prasad Panda
- Institute of Pharmaceutical Research, GLA University, Mathura, Uttar Pradesh, India.
| | - Adarsh Kesharwani
- Institute of Pharmaceutical Research, GLA University, Mathura, Uttar Pradesh, India
| | | | - Dsnbk Prasanth
- KVSR Siddhartha College of Pharmaceutical Sciences, Vijayawada, Andhrapradesh, India
| | - Bhaskara Raju Vatchavai
- Sri Vasavi Institute of Pharmaceutical Sciences, Pedatadepalli, Tadepalligudem, Andhrapradesh, India
| | - P V Kamala Kumari
- Vignan Institute of Pharmaceutical Technology, Duvvada, Visakhapatnam, Andhrapradesh, India
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10
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Nestor CC, Merkley CM, Lehman MN, Hileman SM, Goodman RL. KNDy neurons as the GnRH pulse generator: Recent studies in ruminants. Peptides 2023; 164:171005. [PMID: 36990389 PMCID: PMC10164117 DOI: 10.1016/j.peptides.2023.171005] [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: 12/28/2022] [Revised: 03/10/2023] [Accepted: 03/24/2023] [Indexed: 03/29/2023]
Abstract
This review considers three aspects of recent work on the role of KNDy neurons in GnRH pulse generation in ruminants. First, work on basic mechanisms of pulse generation includes several tests of this hypothesis, all of which support it, and evidence that Kiss1r-containing neurons form a positive feedback circuit with the KNDy neural network that strengthen the activity of this network. The second section on pathways mediating external inputs focuses on the influence of nutrition and photoperiod, and describes the evidence supporting roles for proopiomelanocortin (POMC) and agouti-related peptide (AgRP) afferents to KNDy cells in each of these. Finally, we review studies exploring the potential applications of manipulating signaling by kisspeptin, and the other KNDy peptides, to control reproductive function in domestic animals and conclude that, although these approaches show some promise, they do not have major advantages over current practices at this time.
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Affiliation(s)
- Casey C Nestor
- Department of Animal Science, North Carolina State University, Raleigh, NC, USA
| | | | - Michael N Lehman
- Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - Stanley M Hileman
- Department of Physiology, Pharmacology, and Toxicology, West Virginia University, Morgantown, WV, USA
| | - Robert L Goodman
- Department of Physiology, Pharmacology, and Toxicology, West Virginia University, Morgantown, WV, USA.
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11
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Szeliga A, Podfigurna A, Bala G, Meczekalski B. Decreased neurokinin B as a risk factor of functional hypothalamic amenorrhea. Gynecol Endocrinol 2023; 39:2216313. [PMID: 37224872 DOI: 10.1080/09513590.2023.2216313] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 04/27/2023] [Accepted: 05/15/2023] [Indexed: 05/26/2023] Open
Abstract
BACKGROUND Neurokinin B (NKB) belongs to the tachykinin family of proteins who's regulation is essential for proper function of the reproductive system. It has been shown that patients with functional hypothalamic amenorrhea (FHA) exhibit decreased levels of serum kisspeptin. As kisspeptin secretion is regulated by NKB signaling, it is reasonable to suspect that patients with FHA will also have abnormal NKB secretion. AIM To assess NKB levels in patients with FHA and to determine whether NKB signaling is affected in these patients. We hypothesized that decreased NKB signaling is a factor contributing to the development of the FHA. MATERIALS AND METHODS A total of 147 patients with FHA and 88 healthy age-matched controls were enrolled. Baseline blood samples were drawn from both groups to measure serum concentrations of NKB, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), prolactin (PRL), thyroid-stimulating hormone (TSH), free thyroxine (fT4), cortisol, dehydroepiandrosterone sulfate (DHEA-S), testosterone (T), glucose, and insulin. RESULTS Mean serum NKB levels were found to be decreased significantly in the FHA group when compared with the control group (628.35 ± 324.92 vs. 721.41 ± 337.57 ng/L, respectively p = 0.002). No statistical difference was observed in NKB-1 levels within the FHA group when selecting for normal and decreased body mass index. CONCLUSIONS Patients with FHA were found to have decreased serum NKB concentrations when compared to healthy controls. Abnormal NKB secretion is likely a key factor contributing to development of FHA.
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Affiliation(s)
- Anna Szeliga
- Department of Gynecological Endocrinology, Poznan University of Medical Sciences, Poznan, Poland
| | - Agnieszka Podfigurna
- Department of Gynecological Endocrinology, Poznan University of Medical Sciences, Poznan, Poland
| | - Gregory Bala
- UCD School of Medicine, University College Dublin, Dublin 4, Ireland
| | - Blazej Meczekalski
- Department of Gynecological Endocrinology, Poznan University of Medical Sciences, Poznan, Poland
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12
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Kutlu E, Ozgen LT, Bulut H, Kocyigit A, Ustunova S, Hüseyinbas O, Torun E, Cesur Y. Investigation of irisin's role in pubertal onset physiology in female rats. Peptides 2023; 163:170976. [PMID: 36796677 DOI: 10.1016/j.peptides.2023.170976] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/09/2023] [Accepted: 02/13/2023] [Indexed: 02/16/2023]
Abstract
OBJECTIVE The timing of pubertal development is closely related to metabolic status and energy reserves. It is thought that irisin, which is involved in the regulation of energy metabolism and is shown to be present in the hypothalamo-pituitary-gonadal (HPG) axis, may play a role in this process. In our study, we aimed to investigate the effect of irisin administration on pubertal development and HPG axis in rats. DESIGN-METHODS 36 female rats were included in the study were divided into 3 groups: 100 ng/kg/day irisin treatment group (irisin-100), 50 ng/kg/day irisin treatment group (irisin-50), and control group. On the 38th day, serum samples were taken to determine levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH), estradiol and irisin. Brain hypothalamus samples were taken to determine levels of pulsatile gonadotropin-releasing hormone (GnRH), kisspeptin, neurokinin-B, dynorphin (Dyn), and makorin ring finger protein-3 (MKRN3). RESULTS Vaginal opening and estrus were seen firstly in the irisin-100 group. At the end of the study, the highest rate of vaginal patency was found in the irisin-100 group. Hypothalamic protein expression levels of GnRH, NKB and Kiss1 in homogenates; serum FSH, LH, and estradiol levels were the highest in the irisin-100 group, followed by the irisin-50 and control groups, respectively. Ovarian sizes were significantly greater in the irisin-100 group compared to the other groups. The hypothalamic protein expression levels of MKRN3 and Dyn were the lowest in the irisin-100 group. CONCLUSIONS In this experimental study, irisin triggered the onset of puberty in a dose-dependent manner. Irisin administration caused the excitatory system to dominate in the hypothalamic GnRH pulse generator.
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Affiliation(s)
- Esra Kutlu
- Health Sciences University Istanbul Umraniye Training and Research Hospital, Department of Pediatrics, Division of Pediatric Endocrinology, Umraniye, Istanbul, Turkey.
| | - Lker Tolga Ozgen
- Bezmialem Vakif University, Faculty of Medicine, Department of Pediatrics, Division of Pediatric Endocrinology, Fatih, Istanbul, Turkey
| | - Huri Bulut
- Istinye University, Faculty of Medicine, Department of Biochemistry, Zeytinburnu, Istanbul, Turkey
| | - Abdurrahim Kocyigit
- Bezmialem Vakif University, Faculty of Medicine, Department of Biochemistry, Fatih, Istanbul, Turkey
| | - Savas Ustunova
- Bezmialem Vakif University, Faculty of Medicine, Department of Physiology, Fatih, Istanbul, Turkey
| | - Onder Hüseyinbas
- Bezmialem Vakif University, Faculty of Medicine, Animal Research Laboratory, Fatih, Istanbul, Turkey
| | - Emel Torun
- Bezmialem Vakif University, Faculty of Medicine, Department of Pediatrics, Fatih, Istanbul, Turkey
| | - Yasar Cesur
- Bezmialem Vakif University, Faculty of Medicine, Department of Pediatrics, Division of Pediatric Endocrinology, Fatih, Istanbul, Turkey
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13
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Garza V, West SM, Cardoso RC. Review: Gestational and postnatal nutritional effects on the neuroendocrine control of puberty and subsequent reproductive performance in heifers. Animal 2023; 17 Suppl 1:100782. [PMID: 37567667 DOI: 10.1016/j.animal.2023.100782] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 03/13/2023] [Accepted: 03/17/2023] [Indexed: 08/13/2023] Open
Abstract
Pubertal attainment is an intricate biological process that involves maturation of the reproductive neuroendocrine axis and increased pulsatile release of gonadotropin-releasing hormone (GnRH) and luteinizing hormone. Nutrition is a critical environmental factor controlling the timing of puberty attainment. Nutrient restriction during early postnatal development delays puberty, whereas increased feed intake and adiposity during this period hasten pubertal maturation by imprinting the hypothalamus. Moreover, the dam's nutrition during gestation can program the neuroendocrine system in the developing fetus and has the potential to advance or delay puberty in the offspring. Leptin, a hormone produced primarily by adipose cells, plays an important role in communicating energy status to the brain and regulating sexual maturation. Leptin's regulation of GnRH release is mediated by an upstream neuronal network since GnRH neurons do not contain the leptin receptor. Two groups of neurons located in the arcuate nucleus of the hypothalamus that express neuropeptide Y (NPY), an orexigenic peptide, and alpha melanocyte-stimulating hormone (αMSH), an anorexigenic peptide, are central elements of the neural circuitry that relay inhibitory (NPY) and excitatory (αMSH) inputs to GnRH neurons. Moreover, KNDy neurons, neurons in the arcuate nucleus that co-express kisspeptin, neurokinin B (NKB), and dynorphin, also play a role in the metabolic regulation of puberty. Our studies in beef heifers demonstrate that increased rates of BW gain during early postweaning (4-9 mo of age) result in reduced expression of NPY mRNA, increased expression of proopiomelanocortin and kisspeptin receptor mRNA, reduced NPY inhibitory inputs to GnRH neurons, and increased excitatory αMSH inputs to KNDy neurons. Finally, our most recent data demonstrate that nutrition of the cow during the last two trimesters of gestation can also induce transcriptional and structural changes in hypothalamic neurocircuitries in the heifer progeny that likely persist long-term after birth. Managerial approaches, such as supplementation of the dam during gestation (fetal programming), creep feeding, early weaning, and stair-step nutritional regimens have been developed to exploit brain plasticity and advance pubertal maturation in heifers.
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Affiliation(s)
- Viviana Garza
- Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, TX 77843, USA
| | - Sarah M West
- Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, TX 77843, USA
| | - Rodolfo C Cardoso
- Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, TX 77843, USA.
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14
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Gurule S, Sustaita-Monroe J, Padmanabhan V, Cardoso R. Developmental programming of the neuroendocrine axis by steroid hormones: Insights from the sheep model of PCOS. Front Endocrinol (Lausanne) 2023; 14:1096187. [PMID: 36755919 PMCID: PMC9899912 DOI: 10.3389/fendo.2023.1096187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/06/2023] [Indexed: 01/25/2023] Open
Abstract
The reproductive neuroendocrine system is a key target for the developmental programming effects of steroid hormones during early life. While gonadal steroids play an important role in controlling the physiological development of the neuroendocrine axis, human fetuses are susceptible to adverse programming due to exposure to endocrine disrupting chemicals with steroidal activity, inadvertent use of contraceptive pills during pregnancy, as well as from disease states that result in abnormal steroid production. Animal models provide an unparalleled resource to understand the effects of steroid hormones on the development of the neuroendocrine axis and their role on the developmental origins of health and disease. In female sheep, exposure to testosterone (T) excess during fetal development results in an array of reproductive disorders that recapitulate those seen in women with polycystic ovary syndrome (PCOS), including disrupted neuroendocrine feedback mechanisms, increased pituitary responsiveness to gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) hypersecretion, functional hyperandrogenism, multifollicular ovarian morphology, and premature reproductive failure. Similar to a large proportion of women with PCOS, these prenatally T-treated sheep also manifest insulin resistance and cardiovascular alterations, including hypertension. This review article focuses on the effects of prenatal androgens on the developmental programming of hypothalamic and pituitary alterations in the sheep model of PCOS phenotype, centering specifically on key neurons, neuropeptides, and regulatory pathways controlling GnRH and LH secretion. Insights obtained from the sheep model as well as other animal models of perinatal androgen excess can have important translational relevance to treat and prevent neuroendocrine dysfunction in women with PCOS and other fertility disorders.
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Affiliation(s)
- Sara Gurule
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | | | | | - Rodolfo Cardoso
- Department of Animal Science, Texas A&M University, College Station, TX, United States
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15
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Xu G, Zhao X, Li Z, Hu J, Li X, Li J, Chen Y. Effects of electroacupuncture on the kisspeptin-gonadotropin-releasing hormone (GnRH) /luteinizing hormone (LH) neural circuit abnormalities and androgen receptor expression of kisspeptin/neurokinin B/dynorphin neurons in PCOS rats. J Ovarian Res 2023; 16:15. [PMID: 36650561 PMCID: PMC9844031 DOI: 10.1186/s13048-022-01078-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 12/13/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, anovulation, and polycystic ovaries. Electroacupuncture (EA) can effectively improve hyperandrogenism and increase ovulation frequency in patients with PCOS. Pieces of suggest that androgen activity in the brain is associated with impaired steroid negative feedback in such patients. Studies have shown that EA regulated androgen receptor (AR) expression and local factor levels (such as anti-Müllerian hormone and inhibin B) in the ovary of PCOS rats. However, few studies have explored the effect of EA on androgen activity in the brain. OBJECTIVE This study investigated the effect of EA on the kisspeptin-gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) neural circuit and sex hormone receptor expression in the hypothalamus of PCOS rats. METHODS PCOS signs were induced by letrozole administration, and the induced rats were treated with low-frequency EA at Guan Yuan acupoint (CV4). The effect of EA on PCOS-like signs was evaluated by observing changes in the body weight, ovarian quality, ovarian morphology, and serum sex hormone levels in rats. To explore the mechanism of the effect of EA on PCOS-like signs, the neuropeptide content of the kisspeptin-GnRH/LH neural circuit was assessed using enzyme-linked immunosorbent assay(ELISA); AR and estrogen receptor α (ERα) coexpression on kisspeptin/neurokinin B/dynorphin (KNDy) neurons was determined via triple-label immunofluorescence; and protein and mRNA expression of Kiss1, Ar, Esr1, and kisspeptin receptor (Kiss1r) was evaluated via western blotting and Reverse Transcription-Polymerase Chain Reaction (RT-PCR). RESULTS The results revealed that the estrous cycle of rats in the EA treatment group recovered, and their body and ovary weight reduced; ovarian morphology improved; serum testosterone and LH levels significantly decreased; and kisspeptin, GnRH, and dynorphin levels in hypothalamic arcuate nucleus significantly decreased. Compared with controls, the number of AR/Kiss1-positive cells increased, number of ERα/Kiss1-positive cells decreased, and protein and mRNA expression of Kiss1, Ar, and Kiss1r significantly increased in PCOS rats. However, EA treatment reversed these changes and reduced the expression of Kiss1, Ar, and Kiss1r significantly. CONCLUSION Improvement in the reproductive hallmarks of PCOS rats via EA may be achieved by regulating the kisspeptin-GnRH/LH circuit via androgen activity attenuation. Thus, the results provide an experimental basis for acupuncture as an adjuvant medical therapy on PCOS.
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Affiliation(s)
- Ge Xu
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China ,grid.412540.60000 0001 2372 7462Shanghai University of Traditional Chinese Medicine, Shanghai, 201210 China
| | - Xuedan Zhao
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China ,grid.412540.60000 0001 2372 7462Shanghai University of Traditional Chinese Medicine, Shanghai, 201210 China
| | - Zhihao Li
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China
| | - Junwei Hu
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China
| | - Xu Li
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China
| | - Juanjuan Li
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China
| | - Yuelai Chen
- grid.411480.80000 0004 1799 1816Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, 200032 China
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16
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Merchán M, Coveñas R, Plaza I, Abecia JA, Palacios C. Anatomy of hypothalamic and diencephalic nuclei involved in seasonal fertility regulation in ewes. Front Vet Sci 2023; 10:1101024. [PMID: 36876003 PMCID: PMC9978410 DOI: 10.3389/fvets.2023.1101024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/31/2023] [Indexed: 02/18/2023] Open
Abstract
In this study, we describe in detail the anatomy of nuclei involved in seasonal fertility regulation (SFR) in ewes. For this purpose, the intergeniculate leaflet of the visual thalamus, the caudal hypothalamic arcuate nucleus, and suprachiasmatic, paraventricular and supraoptic nuclei of the rostral hypothalamus were morphometrically and qualitatively analyzed in Nissl-stained serial sections, in the three anatomical planes. In addition, data were collected on calcium-binding proteins and cell phenotypes after immunostaining alternate serial sections for calretinin, parvalbumin and calbindin. For a complete neuroanatomical study, glial architecture was assessed by immunostaining and analyzing alternate sections for glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (IBA1). The results showed a strong microglial and astroglia reaction around the hypothalamic nuclei of interest and around the whole 3rd ventricle of the ewe brain. Moreover, we correlated cytoarchitectonic coordinates of panoramic serial sections with their macroscopic localization and extension in midline sagittal-sectioned whole brain to provide guidelines for microdissecting nuclei involved in SFR.
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Affiliation(s)
- Miguel Merchán
- Animal Production Area, Department of Construction and Agronomy, Faculty of Agricultural and Environmental Sciences, University of Salamanca, Salamanca, Spain.,Laboratory of Neuroanatomy of the Peptidergic Systems, Institute for Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain.,Recognized Research Group - Molecular Bases of Development (Grupo de Investigación Reconocido - Bases Moleculares del Desarrollo - GIR-BMD), University of Salamanca, Salamanca, Spain
| | - Rafael Coveñas
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute for Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain.,Recognized Research Group - Molecular Bases of Development (Grupo de Investigación Reconocido - Bases Moleculares del Desarrollo - GIR-BMD), University of Salamanca, Salamanca, Spain
| | - Ignacio Plaza
- Auditory Neuroplasticity Laboratory, Institute for Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain
| | - José Alfonso Abecia
- Environmental Science Institute (IUCA), University of Zaragoza, Zaragoza, Spain
| | - Carlos Palacios
- Animal Production Area, Department of Construction and Agronomy, Faculty of Agricultural and Environmental Sciences, University of Salamanca, Salamanca, Spain
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17
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Johnson CS, Mermelstein PG. The interaction of membrane estradiol receptors and metabotropic glutamate receptors in adaptive and maladaptive estradiol-mediated motivated behaviors in females. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 168:33-91. [PMID: 36868633 DOI: 10.1016/bs.irn.2022.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Estrogen receptors were initially identified as intracellular, ligand-regulated transcription factors that result in genomic change upon ligand binding. However, rapid estrogen receptor signaling initiated outside of the nucleus was also known to occur via mechanisms that were less clear. Recent studies indicate that these traditional receptors, estrogen receptor α and estrogen receptor β, can also be trafficked to act at the surface membrane. Signaling cascades from these membrane-bound estrogen receptors (mERs) can rapidly alter cellular excitability and gene expression, particularly through the phosphorylation of CREB. A principal mechanism of neuronal mER action has been shown to occur through glutamate-independent transactivation of metabotropic glutamate receptors (mGlu), which elicits multiple signaling outcomes. The interaction of mERs with mGlu has been shown to be important in many diverse functions in females, including driving motivated behaviors. Experimental evidence suggests that a large part of estradiol-induced neuroplasticity and motivated behaviors, both adaptive and maladaptive, occurs through estradiol-dependent mER activation of mGlu. Herein we will review signaling through estrogen receptors, both "classical" nuclear receptors and membrane-bound receptors, as well as estradiol signaling through mGlu. We will focus on how the interactions of these receptors and their downstream signaling cascades are involved in driving motivated behaviors in females, discussing a representative adaptive motivated behavior (reproduction) and maladaptive motivated behavior (addiction).
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Affiliation(s)
- Caroline S Johnson
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Paul G Mermelstein
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States.
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18
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Stress, kisspeptin, and functional hypothalamic amenorrhea. Curr Opin Pharmacol 2022; 67:102288. [PMID: 36103784 DOI: 10.1016/j.coph.2022.102288] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/04/2022] [Accepted: 08/04/2022] [Indexed: 01/25/2023]
Abstract
Functional hypothalamic amenorrhea (FHA) is the most common cause of secondary amenorrhea in women of reproductive age. FHA is predominantly caused by stress, decreased caloric intake, excessive exercise, or a combination thereof. These physical, psychological, and metabolic stressors cause aberration in the pulsatile release of gonadotropin-releasing hormone (GnRH) and subsequently impair function of the hypothalamic-pituitary-ovarian (HPO) axis. Various neurotransmitters acting in the central nervous system are involved in control of the HPO axis and of these, kisspeptin is one of the most important. Corticotropin-releasing hormone (CRH), also inhibits the pulsatile secretion of GnRH and also acts as an intermediary between stress factors and the reproductive system. One of the main ongoing concerns in patients with FHA is chronic hypoestrogenism, a condition, which is associated with sexual dysfunction and infertility. It may also lead to osteoporosis, and predispose to neurodegenerative and cardiovascular diseases. Treatment of FHA requires the elimination of causative factors, however, making the necessary lifestyle changes is not always easy to initiate and maintain. Broadening our knowledge of the complex neural mechanisms regulating reproductive function in which kisspeptin plays a key role can help in the development of new treatment options such as the potential of kisspeptin receptor agonists for patients with FHA.
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19
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Coutinho EA, Esparza LA, Hudson AD, Rizo N, Steffen P, Kauffman AS. Conditional Deletion of KOR (Oprk1) in Kisspeptin Cells Does Not Alter LH Pulses, Puberty, or Fertility in Mice. Endocrinology 2022; 163:6763672. [PMID: 36260530 DOI: 10.1210/endocr/bqac175] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Indexed: 01/26/2023]
Abstract
Classic pharmacological studies suggested that endogenous dynorphin-KOR signaling is important for reproductive neuroendocrine regulation. With the seminal discovery of an interconnected network of hypothalamic arcuate neurons co-expressing kisspeptin, neurokinin B, and dynorphin (KNDy neurons), the KNDy hypothesis was developed to explain how gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) pulses are generated. Key to this hypothesis is dynorphin released from KNDy neurons acting in a paracrine manner on other KNDy neurons via kappa opioid receptor (KOR) signaling to terminate neural "pulse" events. While in vitro evidence supports this aspect of the KNDy hypothesis, a direct in vivo test of the necessity of KOR signaling in kisspeptin neurons for proper LH secretion has been lacking. We therefore conditionally knocked out KOR selectively from kisspeptin neurons of male and female mice and tested numerous reproductive measures, including in vivo LH pulse secretion. Surprisingly, despite validating successful knockout of KOR in kisspeptin neurons, we found no significant effect of kisspeptin cell-specific deletion of KOR on any measure of puberty, LH pulse parameters, LH surges, follicle-stimulating hormone (FSH) levels, estrous cycles, or fertility. These outcomes suggest that the KNDy hypothesis, while sufficient normally, may not be the only neural mechanism for sculpting GnRH and LH pulses, supported by recent findings in humans and mice. Thus, besides normally acting via KOR in KNDy neurons, endogenous dynorphin and other opioids may, under some conditions, regulate LH and FSH secretion via KOR in non-kisspeptin cells or perhaps via non-KOR pathways. The current models for GnRH and LH pulse generation should be expanded to consider such alternate mechanisms.
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Affiliation(s)
- Eulalia A Coutinho
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Lourdes A Esparza
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Alexandra D Hudson
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Nathanael Rizo
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Paige Steffen
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Alexander S Kauffman
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA 92093, USA
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20
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Mills EG, Dhillo WS. Invited review: Translating kisspeptin and neurokinin B biology into new therapies for reproductive health. J Neuroendocrinol 2022; 34:e13201. [PMID: 36262016 PMCID: PMC9788075 DOI: 10.1111/jne.13201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 07/26/2022] [Accepted: 09/06/2022] [Indexed: 12/30/2022]
Abstract
The reproductive neuropeptide kisspeptin has emerged as the master regulator of mammalian reproduction due to its key roles in the initiation of puberty and the control of fertility. Alongside the tachykinin neurokinin B and the endogenous opioid dynorphin, these peptides are central to the hormonal control of reproduction. Building on the expanding body of experimental animal models, interest has flourished with human studies revealing that kisspeptin administration stimulates physiological reproductive hormone secretion in both healthy men and women, as well as patients with common reproductive disorders. In addition, emerging therapeutic roles based on neurokinin B for the management of menopausal flushing, endometriosis and uterine fibroids are increasingly recognised. In this review, we focus on kisspeptin and neurokinin B and their potential application as novel clinical strategies for the management of reproductive disorders.
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Affiliation(s)
- Edouard G. Mills
- Section of Endocrinology and Investigative MedicineImperial College LondonLondonUK
- Department of EndocrinologyImperial College Healthcare NHS TrustLondonUK
| | - Waljit S. Dhillo
- Section of Endocrinology and Investigative MedicineImperial College LondonLondonUK
- Department of EndocrinologyImperial College Healthcare NHS TrustLondonUK
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21
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Moore AM. Impaired steroid hormone feedback in polycystic ovary syndrome: Evidence from preclinical models for abnormalities within central circuits controlling fertility. Clin Endocrinol (Oxf) 2022; 97:199-207. [PMID: 35349177 PMCID: PMC11289760 DOI: 10.1111/cen.14711] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/09/2022] [Accepted: 02/18/2022] [Indexed: 12/24/2022]
Abstract
Polycystic ovary syndrome (PCOS) is the most common endocrinopathy and cause of infertility in women of reproductive age worldwide. Despite diagnostic features of anovulation, polycystic ovarian morphology, and high androgen secretion indicating the syndrome are the result of ovarian dysfunction, alterations to central neuroendocrine circuits that control reproductive capacity may drive PCOS symptoms. Resistance of gonadotrophin-releasing hormone (GnRH) neurons in the hypothalamus to inhibition by sex steroid hormone-negative feedback leads to a rapid frequency of pulsatile gonadotrophin secretion, which, in turn, drives the ovarian features of the disease. As GnRH neurons do not express steroid hormone receptors, impaired negative feedback is hypothesized to occur within an upstream network that controls GnRH pulse generation. This review will discuss the latest work from preclinical animal models of PCOS used to dissect the specific central mechanisms involved in impaired steroid hormone feedback. In particular, this review will focus on research that indicates neurons in the arcuate nucleus of the hypothalamus that express Kisspeptin, Neurokinin B and Dynorphin (KNDy cells) or γ-aminobutyric acid are targets of androgen-mediated impairment of steroid hormone feedback. Finally, this review will explore the development of therapeutic agents targeting neurons that control LH pulse frequency to resolve PCOS symptoms in the clinic.
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Affiliation(s)
- Aleisha M Moore
- Department of Biological Sciences, Brain Health Research Institute, Kent State University, Kent, Ohio, USA
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22
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Semaan SJ, Kauffman AS. Developmental sex differences in the peri-pubertal pattern of hypothalamic reproductive gene expression, including Kiss1 and Tac2, may contribute to sex differences in puberty onset. Mol Cell Endocrinol 2022; 551:111654. [PMID: 35469849 PMCID: PMC9889105 DOI: 10.1016/j.mce.2022.111654] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 04/15/2022] [Accepted: 04/19/2022] [Indexed: 02/03/2023]
Abstract
The mechanisms regulating puberty still remain elusive, as do the underlying causes for sex differences in puberty onset (girls before boys) and pubertal disorders. Neuroendocrine puberty onset is signified by increased pulsatile GnRH secretion, yet how and when various upstream reproductive neural circuits change developmentally to govern this process is poorly understood. We previously reported day-by-day peri-pubertal increases (Kiss1, Tac2) or decreases (Rfrp) in hypothalamic gene expression of female mice, with several brain mRNA changes preceding external pubertal markers. However, similar pubertal measures in males were not previously reported. Here, to identify possible neural sex differences underlying sex differences in puberty onset, we analyzed peri-pubertal males and directly compared them with female littermates. Kiss1 expression in male mice increased over the peri-pubertal period in both the AVPV and ARC nuclei but with lower levels than in females at several ages. Likewise, Tac2 expression in the male ARC increased between juvenile and older peri-pubertal stages but with levels lower than females at most ages. By contrast, both DMN Rfrp expressionand Rfrp neuronal activation strongly decreased in males between juvenile and peri-pubertal stages, but with similar levels as females. Neither ARC KNDy neuronal activation nor Kiss1r expression in GnRH neurons differed between males and females or changed with age. These findings delineate several peri-pubertal changes in neural populations in developing males, with notable sex differences in kisspeptin and NKB neuron developmental patterns. Whether these peri-pubertal hypothalamic sex differences underlie sex differences in puberty onset deserves future investigation.
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Affiliation(s)
- Sheila J Semaan
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA, USA
| | - Alexander S Kauffman
- Department of OBGYN and Reproductive Sciences, University of California San Diego, La Jolla, CA, USA.
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23
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Kisspeptin Modulation of Reproductive Function. ENDOCRINES 2022. [DOI: 10.3390/endocrines3030029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Kisspeptin is a peptide expressed mainly in the infundibular nucleus of the hypothalamus. Kisspeptin plays a crucial role in the regulation of reproductive functions. It is regarded as the most important factor responsible for the control of the hypothalamic–pituitary–gonadal axis, the onset of puberty, and the regulation of menstruation and fertility. Kisspeptin activity influences numerous processes such as steroidogenesis, follicular maturation, ovulation, and ovarian senescence. The identification of kisspeptin receptor mutations that cause hypogonadotropic hypogonadism has initiated studies on the role of kisspeptin in puberty. Pathologies affecting the neurons secreting kisspeptin play a major role in the development of PCOS, functional hypothalamic amenorrhea, and perimenopausal vasomotor symptoms. Kisspeptin analogs (both agonists and antagonists), therefore, may be beneficial as therapy in those afflicted with such pathologies. The aim of this review is to summarize the influence of kisspeptin in the physiology and pathology of the reproductive system in humans, as well as its potential use in therapy.
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24
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Harlow K, Griesgraber MJ, Seman AD, Shuping SL, Sommer JR, Griffith EH, Hileman SM, Nestor CC. The impact of undernutrition on KNDy (kisspeptin/neurokinin B/dynorphin) neurons in female lambs. J Neuroendocrinol 2022; 34:e13135. [PMID: 35579068 PMCID: PMC9286635 DOI: 10.1111/jne.13135] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 03/25/2022] [Accepted: 03/27/2022] [Indexed: 11/30/2022]
Abstract
Undernutrition limits reproduction through inhibition of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) secretion. Because KNDy neurons coexpress neuropeptides that play stimulatory (kisspeptin and neurokinin B [NKB]) and inhibitory (dynorphin) roles in pulsatile GnRH/LH release, we hypothesized that undernutrition would inhibit kisspeptin and NKB expression at the same time as increasing dynorphin expression. Fifteen ovariectomized lambs were either fed to maintain pre-study body weight (controls) or feed-restricted to lose 20% of pre-study body weight (FR) over 13 weeks. Blood samples were collected and plasma from weeks 0 and 13 were assessed for LH by radioimmunoassay. At week 13, animals were killed, and brain tissue was processed for assessment of KNDy peptide mRNA or protein expression. Mean LH and LH pulse amplitude were lower in FR lambs compared to controls. We observed lower mRNA abundance for kisspeptin within KNDy neurons of FR lambs compared to controls with no significant change in mRNA for NKB or dynorphin. We also observed that FR lambs had fewer numbers of arcuate nucleus kisspeptin and NKB perikarya compared to controls. These findings support the idea that KNDy neurons are important for regulating reproduction during undernutrition in female sheep.
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Affiliation(s)
- KaLynn Harlow
- Department of Animal ScienceNorth Carolina State UniversityRaleighNCUSA
| | - Max J. Griesgraber
- Department of Physiology and PharmacologyWest Virginia UniversityMorgantownWVUSA
| | - Andrew D. Seman
- Department of Physiology and PharmacologyWest Virginia UniversityMorgantownWVUSA
| | - Sydney L. Shuping
- Department of Animal ScienceNorth Carolina State UniversityRaleighNCUSA
| | - Jeffrey R. Sommer
- Department of Animal ScienceNorth Carolina State UniversityRaleighNCUSA
| | | | - Stanley M. Hileman
- Department of Physiology and PharmacologyWest Virginia UniversityMorgantownWVUSA
- Department of NeuroscienceWest Virginia UniversityMorgantownWVUSA
| | - Casey C Nestor
- Department of Animal ScienceNorth Carolina State UniversityRaleighNCUSA
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25
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Sheep as a model for neuroendocrinology research. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 189:1-34. [PMID: 35595346 DOI: 10.1016/bs.pmbts.2022.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Animal models remain essential to understand the fundamental mechanisms of physiology and pathology. Particularly, the complex and dynamic nature of neuroendocrine cells of the hypothalamus make them difficult to study. The neuroendocrine systems of the hypothalamus are critical for survival and reproduction, and are highly conserved throughout vertebrate evolution. Their roles in controlling body metabolism, growth and body composition, stress, electrolyte balance, and reproduction, have been intensively studied, and have yielded groundbreaking discoveries. Many of these discoveries would not have been feasible without the use of the domestic sheep (Ovis aries). The sheep has been used for decades to study the neuroendocrine systems of the hypothalamus and has become a model for human neuroendocrinology. The aim of this chapter is to review some of the profound biomedical discoveries made possible by the use of sheep. The advantages and limitations of sheep as a neuroendocrine model will be discussed. While no animal model can perfectly recapitulate a human disease or condition, sheep are invaluable for enabling manipulations not possible in human subjects and isolating physiologic variables to garner insight into neuroendocrinology and associated pathologies.
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26
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McCartney CR, Campbell RE, Marshall JC, Moenter SM. The role of gonadotropin-releasing hormone neurons in polycystic ovary syndrome. J Neuroendocrinol 2022; 34:e13093. [PMID: 35083794 PMCID: PMC9232905 DOI: 10.1111/jne.13093] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 12/21/2021] [Accepted: 01/11/2022] [Indexed: 01/28/2023]
Abstract
Given the critical central role of gonadotropin-releasing hormone (GnRH) neurons in fertility, it is not surprising that the GnRH neural network is implicated in the pathology of polycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility. Although many symptoms of PCOS relate most proximately to ovarian dysfunction, the central reproductive neuroendocrine system ultimately drives ovarian function through its regulation of anterior pituitary gonadotropin release. The typical cyclical changes in frequency of GnRH release are often absent in women with PCOS, resulting in a persistent high-frequency drive promoting gonadotropin changes (i.e., relatively high luteinizing hormone and relatively low follicle-stimulating hormone concentrations) that contribute to ovarian hyperandrogenemia and ovulatory dysfunction. However, the specific mechanisms underpinning GnRH neuron dysfunction in PCOS remain unclear. Here, we summarize several preclinical and clinical studies that explore the causes of aberrant GnRH secretion in PCOS and the role of disordered GnRH secretion in PCOS pathophysiology.
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Affiliation(s)
- Christopher R. McCartney
- Center for Research in Reproduction and Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA
| | - Rebecca E. Campbell
- Centre for Neuroendocrinology and Department of PhysiologySchool of Biomedical SciencesUniversity of OtagoDunedinNew Zealand
| | - John C. Marshall
- Center for Research in Reproduction and Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA
| | - Suzanne M. Moenter
- Departments of Molecular & Integrative PhysiologyInternal MedicineObstetrics and GynecologyUniversity of MichiganAnn ArborMIUSA
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27
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Terasawa E. The mechanism underlying the pubertal increase in pulsatile GnRH release in primates. J Neuroendocrinol 2022; 34:e13119. [PMID: 35491543 PMCID: PMC9232993 DOI: 10.1111/jne.13119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 02/17/2022] [Accepted: 03/01/2022] [Indexed: 11/29/2022]
Abstract
In primates, the gonatotropin-releasing hormone (GnRH) neurosecretory system, consisting of GnRH, kisspeptin, and neurokinin B neurons, is active during the neonatal/early infantile period. During the late infantile period, however, activity of the GnRH neurosecretory system becomes minimal as a result of gonadal steroid independent central inhibition, and this suppressed GnRH neurosecretory state continues throughout the prepubertal period. At the initiation of puberty, the GnRH neurosecretory system becomes active again because of the decrease in central inhibition. During the progress of puberty, kisspeptin and neurokinin B signaling to GnRH neurons further increases, resulting in the release of gonadotropins and subsequent gonadal maturation, and hence puberty. This review further discusses potential substrates of central inhibition and subsequent pubertal modification of the GnRH neurosecretory system by the pubertal increase in steroid hormones, which ensures the regulation of adult reproductive function.
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Affiliation(s)
- Ei Terasawa
- Department of Pediatrics and Wisconsin National Primate Research CenterUniversity of Wisconsin‐MadisonMadisonWIUSA
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28
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Dardente H, Simonneaux V. GnRH and the photoperiodic control of seasonal reproduction: Delegating the task to kisspeptin and RFRP-3. J Neuroendocrinol 2022; 34:e13124. [PMID: 35384117 DOI: 10.1111/jne.13124] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/22/2022] [Accepted: 03/03/2022] [Indexed: 10/18/2022]
Abstract
Synchronization of mammalian breeding activity to the annual change of photoperiod and environmental conditions is of the utmost importance for individual survival and species perpetuation. Subsequent to the early 1960s, when the central role of melatonin in this adaptive process was demonstrated, our comprehension of the mechanisms through which light regulates gonadal activity has increased considerably. The current model for the photoperiodic neuroendocrine system points to pivotal roles for the melatonin-sensitive pars tuberalis (PT) and its seasonally-regulated production of thyroid-stimulating hormone (TSH), as well as for TSH-sensitive hypothalamic tanycytes, radial glia-like cells located in the basal part of the third ventricle. Tanycytes respond to TSH through increased expression of thyroid hormone (TH) deiodinase 2 (Dio2), which leads to heightened production of intrahypothalamic triiodothyronine (T3) during longer days of spring and summer. There is strong evidence that this local, long-day driven, increase in T3 links melatonin input at the PT to gonadotropin-releasing hormone (GnRH) output, to align breeding with the seasons. The mechanism(s) through which T3 impinges upon GnRH remain(s) unclear. However, two distinct neuronal populations of the medio-basal hypothalamus, which express the (Arg)(Phe)-amide peptides kisspeptin and RFamide-related peptide-3, appear to be well-positioned to relay this seasonal T3 message towards GnRH neurons. Here, we summarize our current understanding of the cellular, molecular and neuroendocrine players, which keep track of photoperiod and ultimately govern GnRH output and seasonal breeding.
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Affiliation(s)
- Hugues Dardente
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | - Valérie Simonneaux
- Institute for Cellular and Integrative Neuroscience, University of Strasbourg, Strasbourg, France
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29
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Mun SH, Oh HJ, Kwon JY. Response of Pituitary Cells and Tissues to Neurokinin B and F in the Nile tilapia. Dev Reprod 2022; 26:13-21. [PMID: 35528319 PMCID: PMC9042391 DOI: 10.12717/dr.2022.26.1.13] [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: 12/07/2021] [Revised: 02/23/2022] [Accepted: 03/06/2022] [Indexed: 11/17/2022]
Abstract
Neurokinin B (NKB) is a neuropeptide involved in the regulation of reproductive
endocrine system of vertebrate animals, including fish. However, the pathway of
NKB action in fish has not been clearly elucidated. In order to clarify the
effect of NKB and NKF (neurokinin F) on gonadotropic hormone (GTH) gene
expression in the pituitary, we studied the changes of LHβ and
FSHβ gene expressions by using two different pituitary culture methods
(whole pituitary culture or dispersed pituitary cell culture). Pituitaries were
removed from mature female and male Nile tilapia. Changes of LHβ and
FSHβ gene expressions were measured and compared after the treatment with
NKB or NKF peptides at concentrations 0 to 1,000 nM. Expression of GTH genes in
the whole pituitary cultures treated with NKB or NKF peptides did not show
significant difference except in female at one concentration when treated with
NKF. On the contrary, there were significant changes of GTH gene expressions in
the dispersed pituitary cell cultures when treated with NKB and NKF peptides.
These results suggest that dispersed pituitary cell culture is more relevant
than whole pituitary culture in studying the function of pituitary, and that NKB
and NKF could act directly on the pituitary to regulate the expression of GTH
genes.
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Affiliation(s)
- Seong Hee Mun
- Dept. of Aquatic Life Medical Science, Sunmoon University, Asan 31460, Korea
| | - Hyeon Ji Oh
- Dept. of Aquatic Life Medical Science, Sunmoon University, Asan 31460, Korea
| | - Joon Yeong Kwon
- Dept. of Aquatic Life Medical Science, Sunmoon University, Asan 31460, Korea
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30
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Xie Q, Kang Y, Zhang C, Xie Y, Wang C, Liu J, Yu C, Zhao H, Huang D. The Role of Kisspeptin in the Control of the Hypothalamic-Pituitary-Gonadal Axis and Reproduction. Front Endocrinol (Lausanne) 2022; 13:925206. [PMID: 35837314 PMCID: PMC9273750 DOI: 10.3389/fendo.2022.925206] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/30/2022] [Indexed: 01/07/2023] Open
Abstract
The discovery of kisspeptin as a critical central regulatory factor of GnRH release has given people a novel understanding of the neuroendocrine regulation in human reproduction. Kisspeptin activates the signaling pathway by binding to its receptor kisspeptin receptor (KISS1R) to promote GnRH secretion, thereby regulating the hypothalamic-pituitary-gonadal axis (HPG) axis. Recent studies have shown that kisspeptin neurons located in arcuate nucleus (ARC) co-express neurokinin B (NKB) and dynorphin (Dyn). Such neurons are called KNDy neurons. KNDy neurons participate in the positive and negative feedback of estrogen to GnRH secretion. In addition, kisspeptin is a key factor in the initiation of puberty, and also regulates the processes of female follicle development, oocyte maturation, and ovulation through the HPG axis. In male reproduction, kisspeptin also plays an important role, getting involved in the regulation of Leydig cells, spermatogenesis, sperm functions and reproductive behaviors. Mutations in the KISS1 gene or disorders of the kisspeptin/KISS1R system may lead to clinical symptoms such as idiopathic hypogonadotropic hypogonadism (iHH), central precocious puberty (CPP) and female infertility. Understanding the influence of kisspeptin on the reproductive axis and related mechanisms will help the future application of kisspeptin in disease diagnosis and treatment. In this review, we critically appraise the role of kisspeptin in the HPG axis, including its signaling pathways, negative and positive feedback mechanisms, and its control on female and male reproduction.
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Affiliation(s)
- Qinying Xie
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yafei Kang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chenlu Zhang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ye Xie
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chuxiong Wang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiang Liu
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Caiqian Yu
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hu Zhao
- Department of Human Anatomy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Donghui Huang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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31
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Emanuel RHK, Roberts J, Docherty PD, Lunt H, Campbell RE, Möller K. A review of the hormones involved in the endocrine dysfunctions of polycystic ovary syndrome and their interactions. Front Endocrinol (Lausanne) 2022; 13:1017468. [PMID: 36457554 PMCID: PMC9705998 DOI: 10.3389/fendo.2022.1017468] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/27/2022] [Indexed: 11/16/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) affects up to 20% of women but remains poorly understood. It is a heterogeneous condition with many potential comorbidities. This review offers an overview of the dysregulation of the reproductive and metabolic systems associated with PCOS. Review of the literature informed the development of a comprehensive summarizing 'wiring' diagram of PCOS-related features. This review provides a justification for each diagram aspect from the relevant academic literature, and explores the interactions between the hypothalamus, ovarian follicles, adipose tissue, reproductive hormones and other organ systems. The diagram will provide an efficient and useful tool for those researching and treating PCOS to understand the current state of knowledge on the complexity and variability of PCOS.
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Affiliation(s)
- Rebecca H. K. Emanuel
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand
| | - Josh Roberts
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand
| | - Paul D. Docherty
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
- *Correspondence: Paul D. Docherty,
| | - Helen Lunt
- Diabetes Services, Te Whatu Ora Waitaha Canterbury, Canterbury, New Zealand
- Department of Medicine, University of Otago, Christchurch, New Zealand
| | - Rebecca E. Campbell
- School of Biomedical Sciences, Department of Physiology, Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
| | - Knut Möller
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
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32
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Jamieson BB, Moore AM, Lohr DB, Thomas SX, Coolen LM, Lehman MN, Campbell RE, Piet R. Prenatal androgen treatment impairs the suprachiasmatic nucleus arginine-vasopressin to kisspeptin neuron circuit in female mice. Front Endocrinol (Lausanne) 2022; 13:951344. [PMID: 35992143 PMCID: PMC9388912 DOI: 10.3389/fendo.2022.951344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 07/06/2022] [Indexed: 01/13/2023] Open
Abstract
Polycystic ovary syndrome (PCOS) is associated with elevated androgen and luteinizing hormone (LH) secretion and with oligo/anovulation. Evidence indicates that elevated androgens impair sex steroid hormone feedback regulation of pulsatile LH secretion. Hyperandrogenemia in PCOS may also disrupt the preovulatory LH surge. The mechanisms through which this might occur, however, are not fully understood. Kisspeptin (KISS1) neurons of the rostral periventricular area of the third ventricle (RP3V) convey hormonal cues to gonadotropin-releasing hormone (GnRH) neurons. In rodents, the preovulatory surge is triggered by these hormonal cues and coincident timing signals from the central circadian clock in the suprachiasmatic nucleus (SCN). Timing signals are relayed to GnRH neurons, in part, via projections from SCN arginine-vasopressin (AVP) neurons to RP3VKISS1 neurons. Because rodent SCN cells express androgen receptors (AR), we hypothesized that these circuits are impaired by elevated androgens in a mouse model of PCOS. In prenatally androgen-treated (PNA) female mice, SCN Ar expression was significantly increased compared to that found in prenatally vehicle-treated mice. A similar trend was seen in the number of Avp-positive SCN cells expressing Ar. In the RP3V, the number of kisspeptin neurons was preserved. Anterograde tract-tracing, however, revealed reduced SCNAVP neuron projections to the RP3V and a significantly lower proportion of RP3VKISS1 neurons with close appositions from SCNAVP fibers. Functional assessments showed, on the other hand, that RP3VKISS1 neuron responses to AVP were maintained in PNA mice. These findings indicate that PNA changes some of the neural circuits that regulate the preovulatory surge. These impairments might contribute to ovulatory dysfunction in PNA mice modeling PCOS.
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Affiliation(s)
- Bradley B. Jamieson
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Aleisha M. Moore
- Brain Health Research Institute and Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Dayanara B. Lohr
- Brain Health Research Institute and Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Simone X. Thomas
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Lique M. Coolen
- Brain Health Research Institute and Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Michael N. Lehman
- Brain Health Research Institute and Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - Rebecca E. Campbell
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
| | - Richard Piet
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, Dunedin, New Zealand
- Brain Health Research Institute and Department of Biological Sciences, Kent State University, Kent, OH, United States
- *Correspondence: Richard Piet,
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33
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Moore AM, Lohr DB, Coolen LM, Lehman MN. Prenatal Androgen Exposure Alters KNDy Neurons and Their Afferent Network in a Model of Polycystic Ovarian Syndrome. Endocrinology 2021; 162:bqab158. [PMID: 34346492 PMCID: PMC8402932 DOI: 10.1210/endocr/bqab158] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Indexed: 02/08/2023]
Abstract
Polycystic ovarian syndrome (PCOS), the most common endocrinopathy affecting women worldwide, is characterized by elevated luteinizing hormone (LH) pulse frequency due to the impaired suppression of gonadotrophin-releasing hormone (GnRH) release by steroid hormone negative feedback. Although neurons that co-express kisspeptin, neurokinin B, and dynorphin (KNDy cells) were recently defined as the GnRH/LH pulse generator, little is understood about their role in the pathogenesis of PCOS. We used a prenatal androgen-treated (PNA) mouse model of PCOS to determine whether changes in KNDy neurons or their afferent network underlie altered negative feedback. First, we identified elevated androgen receptor gene expression in KNDy cells of PNA mice, whereas progesterone receptor and dynorphin gene expression was significantly reduced, suggesting elevated androgens in PCOS disrupt progesterone negative feedback via direct actions upon KNDy cells. Second, we discovered GABAergic and glutamatergic synaptic input to KNDy neurons was reduced in PNA mice. Retrograde monosynaptic tract-tracing revealed a dramatic reduction in input originates from sexually dimorphic afferents in the preoptic area, anteroventral periventricular nucleus, anterior hypothalamic area and lateral hypothalamus. These results reveal 2 sites of neuronal alterations potentially responsible for defects in negative feedback in PCOS: changes in gene expression within KNDy neurons, and changes in synaptic inputs from steroid hormone-responsive hypothalamic regions. How each of these changes contribute to the neuroendocrine phenotype seen in in PCOS, and the role of specific sets of upstream KNDy afferents in the process, remains to be determined.
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Affiliation(s)
- Aleisha M Moore
- Department of Biological Sciences, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
| | - Dayanara B Lohr
- Department of Biological Sciences, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
| | - Lique M Coolen
- Department of Biological Sciences, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
| | - Michael N Lehman
- Department of Biological Sciences, Kent State University, Kent, OH 44242, USA
- Brain Health Research Institute, Kent State University, Kent, OH 44242, USA
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Harlow K, Renwick AN, Shuping SL, Sommer JR, Lents CA, Knauer MT, Nestor CC. Evidence that pubertal status impacts KNDy neurons in the gilt. Biol Reprod 2021; 105:1533-1544. [PMID: 34643223 DOI: 10.1093/biolre/ioab189] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 12/26/2022] Open
Abstract
Puberty onset is a complex physiological process which enables the capacity for reproduction through increased gonadotropin-releasing hormone (GnRH), and subsequently luteinizing hormone (LH), secretion. While cells that coexpress kisspeptin, neurokinin B (NKB), and dynorphin in the hypothalamic arcuate nucleus (ARC) are believed to govern the timing of puberty, the degree to which KNDy neurons exist and are regulated by pubertal status remains to be determined in the gilt. Hypothalamic tissue from prepubertal and postpubertal, early follicular phase gilts was used to determine the expression of kisspeptin, NKB, and dynorphin within the ARC. Fluorescent in situ hybridization revealed that the majority (> 74%) of ARC neurons that express mRNA for kisspeptin coexpressed mRNA for NKB and dynorphin. There were fewer ARC cells that expressed mRNA for dynorphin in postpubertal gilts compared to prepubertal gilts (P < 0.05), but the number of ARC cells expressing mRNA for kisspeptin or NKB was not different between groups. Within KNDy neurons, mRNA abundance for kisspeptin, NKB, and dynorphin of postpubertal gilts was the same as, less than, and greater than, respectively, prepubertal gilts. Immunostaining for kisspeptin did not differ between prepubertal and postpubertal gilts, but there were fewer NKB immunoreactive fibers in postpubertal gilts compared to prepubertal gilts (P < 0.05). Together, these data reveal novel information about KNDy neurons in gilts and supports the idea that NKB and dynorphin play a role in puberty onset in the female pig.
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Affiliation(s)
- KaLynn Harlow
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695 USA
| | - Allison N Renwick
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695 USA
| | - Sydney L Shuping
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695 USA
| | - Jeffrey R Sommer
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695 USA
| | - Clay A Lents
- USDA, ARS, U.S. Meat Animal Research Center, Livestock Biosystems Research Unit, Clay Center, NE 68966-0166, USA
| | - Mark T Knauer
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695 USA
| | - Casey C Nestor
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695 USA
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Chandra K, Banerjee A, Das M. Epigenetic and transcriptional regulation of GnRH gene under altered metabolism and ageing. THE NUCLEUS 2021. [DOI: 10.1007/s13237-021-00374-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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Analyses of Molecular Characteristics and Enzymatic Activities of Ovine HSD17B3. Animals (Basel) 2021; 11:ani11102876. [PMID: 34679897 PMCID: PMC8532638 DOI: 10.3390/ani11102876] [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: 08/06/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 11/16/2022] Open
Abstract
17β-hydroxysteroid dehydrogenase type 3 (HSD17B3) converts androstenedione (A4) into testosterone (T), which regulates sex steroid production. Because various mutations of the HSD17B3 gene cause disorder of sex differentiation (DSD) in multiple mammalian species, it is very important to reveal the molecular characteristics of this gene in various species. Here, we revealed the open reading frame of the ovine HSD17B3 gene. Enzymatic activities of ovine HSD17B3 and HSD17B1 for converting A4 to T were detected using ovine androgen receptor-mediated transactivation in reporter assays. Although HSD17B3 also converted estrone to estradiol, this activity was much weaker than those of HSD17B1. Although ovine HSD17B3 has an amino acid sequence that is conserved compared with other mammalian species, it possesses two amino acid substitutions that are consistent with the reported variants of human HSD17B3. Substitutions of these amino acids in ovine HSD17B3 for those in human did not affect the enzymatic activities. However, enzymatic activities declined upon missense mutations of the HSD17B3 gene associated with 46,XY DSD, affecting amino acids that are conserved between these two species. The present study provides basic information and tools to investigate the molecular mechanisms behind DSD not only in ovine, but also in various mammalian species.
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Aerts EG, Harlow K, Griesgraber MJ, Bowdridge EC, Hardy SL, Nestor CC, Hileman SM. Kisspeptin, Neurokinin B, and Dynorphin Expression during Pubertal Development in Female Sheep. BIOLOGY 2021; 10:biology10100988. [PMID: 34681086 PMCID: PMC8533601 DOI: 10.3390/biology10100988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/16/2021] [Accepted: 09/25/2021] [Indexed: 12/14/2022]
Abstract
The neural mechanisms underlying increases in gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion that drive puberty onset are unknown. Neurons coexpressing kisspeptin, neurokinin B (NKB), and dynorphin, i.e., KNDy neurons, are important as kisspeptin and NKB are stimulatory, and dynorphin inhibitory, to GnRH secretion. Given this, we hypothesized that kisspeptin and NKB expression would increase, but that dynorphin expression would decrease, with puberty. We collected blood and hypothalamic tissue from ovariectomized lambs implanted with estradiol at five, six, seven, eight (puberty), and ten months of age. Mean LH values and LH pulse frequency were the lowest at five to seven months, intermediate at eight months, and highest at ten months. Kisspeptin and NKB immunopositive cell numbers did not change with age. Numbers of cells expressing mRNA for kisspeptin, NKB, or dynorphin were similar at five, eight, and ten months of age. Age did not affect mRNA expression per cell for kisspeptin or NKB, but dynorphin mRNA expression per cell was elevated at ten months versus five months. Thus, neither KNDy protein nor mRNA expression changed in a predictable manner during pubertal development. These data raise the possibility that KNDy neurons, while critical, may await other inputs for the initiation of puberty.
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Affiliation(s)
- Eliana G. Aerts
- Department of Physiology and Pharmacology, West Virginia University, P.O. Box 9229, Morgantown, WV 26506, USA; (E.G.A.); (M.J.G.); (E.C.B.); (S.L.H.)
| | - KaLynn Harlow
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695, USA; (K.H.); (C.C.N.)
| | - Max J. Griesgraber
- Department of Physiology and Pharmacology, West Virginia University, P.O. Box 9229, Morgantown, WV 26506, USA; (E.G.A.); (M.J.G.); (E.C.B.); (S.L.H.)
| | - Elizabeth C. Bowdridge
- Department of Physiology and Pharmacology, West Virginia University, P.O. Box 9229, Morgantown, WV 26506, USA; (E.G.A.); (M.J.G.); (E.C.B.); (S.L.H.)
| | - Steven L. Hardy
- Department of Physiology and Pharmacology, West Virginia University, P.O. Box 9229, Morgantown, WV 26506, USA; (E.G.A.); (M.J.G.); (E.C.B.); (S.L.H.)
| | - Casey C Nestor
- Department of Animal Science, North Carolina State University, Raleigh, NC 27695, USA; (K.H.); (C.C.N.)
| | - Stanley M. Hileman
- Department of Physiology and Pharmacology, West Virginia University, P.O. Box 9229, Morgantown, WV 26506, USA; (E.G.A.); (M.J.G.); (E.C.B.); (S.L.H.)
- Department of Neuroscience, West Virginia University, Morgantown, WV 26506, USA
- Correspondence: ; Tel.: +1-304-293-1502; Fax: +1-304-293-3850
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Prenatal Androgen Treatment Does Not Alter the Firing Activity of Hypothalamic Arcuate Kisspeptin Neurons in Female Mice. eNeuro 2021; 8:ENEURO.0306-21.2021. [PMID: 34503965 PMCID: PMC8482853 DOI: 10.1523/eneuro.0306-21.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 09/06/2021] [Accepted: 09/07/2021] [Indexed: 11/21/2022] Open
Abstract
Neuroendocrine control of reproduction is disrupted in many individuals with polycystic ovary syndrome (PCOS), who present with increased luteinizing hormone (LH), and presumably gonadotropin-releasing hormone (GnRH), release frequency, and high androgen levels. Prenatal androgenization (PNA) recapitulates these phenotypes in primates and rodents. Female offspring of mice injected with dihydrotestosterone (DHT) on gestational days 16-18 exhibit disrupted estrous cyclicity, increased LH and testosterone, and increased GnRH neuron firing rate as adults. PNA also alters the developmental trajectory of GnRH neuron firing rates, markedly blunting the prepubertal peak in firing that occurs in three-week (3wk)-old controls. GnRH neurons do not express detectable androgen receptors and are thus probably not the direct target of DHT. Rather, PNA likely alters GnRH neuronal activity by modulating upstream neurons, such as hypothalamic arcuate neurons co-expressing kisspeptin, neurokinin B (gene Tac2), and dynorphin, also known as KNDy neurons. We hypothesized PNA treatment changes firing rates of KNDy neurons in a similar age-dependent manner as GnRH neurons. We conducted targeted extracellular recordings (0.5-2 h) of Tac2-identified KNDy neurons from control and PNA mice at 3wks of age and in adulthood. About half of neurons were quiescent (<0.005 Hz). Long-term firing rates of active cells varied, suggestive of episodic activity, but were not different among groups. Short-term burst firing was also similar. We thus reject the hypothesis that PNA alters the firing rate of KNDy neurons. This does not preclude altered neurosecretory output of KNDy neurons, involvement of other neuronal populations, or in vivo networks as critical drivers of altered GnRH firing rates in PNA mice.
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Faykoo-Martinez M, Kalinowski LM, Holmes MM. Neuroendocrine regulation of pubertal suppression in the naked mole-rat: What we know and what comes next. Mol Cell Endocrinol 2021; 534:111360. [PMID: 34116130 DOI: 10.1016/j.mce.2021.111360] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/20/2021] [Accepted: 06/03/2021] [Indexed: 01/13/2023]
Abstract
Puberty is a key developmental milestone that marks an individual's maturation in several ways including, but not limited to, reproductive maturation, changes in behaviors and neural organization. The timing at which puberty occurs is variable both within individuals of the same species and between species. These variations can be aligned with ecological cues that delay or suppress puberty. Naked mole-rats are colony-living rodents where reproduction is restricted to a few animals; all other animals are pubertally-suppressed. Animals removed from suppressive colony cues can reproductively mature, presenting the unique opportunity to study adult-onset puberty. Recently, we found that RFRP-3 administration sustains pubertal delay in naked mole-rats removed from colony. In this review, we explore what is known about regulators that control puberty onset, the role of stress/social status in pubertal timing, the status of knowledge of pubertal suppression in naked mole-rats and what comes next.
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Affiliation(s)
| | | | - Melissa M Holmes
- Department of Cell and Systems Biology, University of Toronto, Canada; Department of Psychology, University of Toronto Mississauga, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Canada
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Mohr MA, Wong AM, Sukumar G, Dalgard CL, Hong W, Wu TJ, Wu YE, Micevych PE. RNA-sequencing of AVPV and ARH reveals vastly different temporal and transcriptomic responses to estradiol in the female rat hypothalamus. PLoS One 2021; 16:e0256148. [PMID: 34407144 PMCID: PMC8372949 DOI: 10.1371/journal.pone.0256148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 07/30/2021] [Indexed: 11/18/2022] Open
Abstract
In females, estrogens have two main modes of action relating to gonadotropin secretion: positive feedback and negative feedback. Estrogen positive and negative feedback are controlled by different regions of the hypothalamus: the preoptic area/anterior portion (mainly the anteroventral periventricular nucleus, AVPV) of the hypothalamus is associated with estrogen positive feedback while the mediobasal hypothalamus (mainly the arcuate nucleus of the hypothalamus, ARH), is associated with estrogen negative feedback. In this study, we examined the temporal pattern of gene transcription in these two regions following estrogen treatment. Adult, ovariectomized, Long Evans rats received doses of estradiol benzoate (EB) or oil every 4 days for 3 cycles. On the last EB priming cycle, hypothalamic tissues were dissected into the AVPV+ and ARH+ at 0 hrs (baseline/oil control), 6 hrs, or 24 hrs after EB treatment. RNA was extracted and sequenced using bulk RNA sequencing. Differential gene analysis, gene ontology, and weighted correlation network analysis (WGCNA) was performed. Overall, we found that the AVPV+ and ARH+ respond differently to estradiol stimulation. In both regions, estradiol treatment resulted in more gene up-regulation than down-regulation. S100g was very strongly up-regulated by estradiol in both regions at 6 and 24 hrs after EB treatment. In the AVPV+ the highest number of differentially expressed genes occurred 24 hrs after EB. In the ARH+, the highest number of genes differentially expressed by EB occurred between 6 and 24 hrs after EB, while in the AVPV+, the fewest genes changed their expression between these time points, demonstrating a temporal difference in the way that EB regulates transcription these two areas. Several genes strongly implicated in gonadotropin release were differentially affected by estradiol including Esr1, encoding estrogen receptor-α and Kiss1, encoding kisspeptin. As an internal validation, Kiss1 was up-regulated in the AVPV+ and down-regulated in the ARH+. Gene network analysis revealed the vastly different clustering of genes modulated by estradiol in the AVPV+ compared with the ARH+. These results indicate that gene expression in these two hypothalamic regions have specific responses to estradiol in timing and direction.
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Affiliation(s)
- Margaret A. Mohr
- Dept of Neurobiology, and the Laboratory of Neuroendocrinology of the Brain Research Institute, UCLA DGSOM, Los Angeles, California, United States of America
| | - Angela M. Wong
- Dept of Neurobiology, and the Laboratory of Neuroendocrinology of the Brain Research Institute, UCLA DGSOM, Los Angeles, California, United States of America
| | - Gauthaman Sukumar
- Dept of Gynecological Surgery and Obstetrics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Clifton L. Dalgard
- Dept of Gynecological Surgery and Obstetrics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Weizhe Hong
- Dept of Neurobiology, and the Laboratory of Neuroendocrinology of the Brain Research Institute, UCLA DGSOM, Los Angeles, California, United States of America
| | - T. John Wu
- Dept of Gynecological Surgery and Obstetrics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Ye Emily Wu
- Dept of Neurobiology, and the Laboratory of Neuroendocrinology of the Brain Research Institute, UCLA DGSOM, Los Angeles, California, United States of America
| | - Paul E. Micevych
- Dept of Neurobiology, and the Laboratory of Neuroendocrinology of the Brain Research Institute, UCLA DGSOM, Los Angeles, California, United States of America
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Sucquart IE, Nagarkar R, Edwards MC, Rodriguez Paris V, Aflatounian A, Bertoldo MJ, Campbell RE, Gilchrist RB, Begg DP, Handelsman DJ, Padmanabhan V, Anderson RA, Walters KA. Neurokinin 3 Receptor Antagonism Ameliorates Key Metabolic Features in a Hyperandrogenic PCOS Mouse Model. Endocrinology 2021; 162:6125280. [PMID: 33522579 DOI: 10.1210/endocr/bqab020] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Indexed: 02/06/2023]
Abstract
Polycystic ovary syndrome (PCOS) is a prevalent endocrine condition characterized by a range of endocrine, reproductive, and metabolic abnormalities. At present, management of women with PCOS is suboptimal as treatment is only symptomatic. Clinical and experimental advances in our understanding of PCOS etiology support a pivotal role for androgen neuroendocrine actions in PCOS pathogenesis. Hyperandrogenism is a key PCOS trait and androgen actions play a role in regulating the kisspeptin-/neurokinin B-/dynorphin (KNDy) system. This study aimed to investigate if targeted antagonism of neurokinin B signaling through the neurokinin 3 receptor (NK3R) would reverse PCOS traits in a dihydrotestosterone (DHT)-induced mouse model of PCOS. After 3 months, DHT exposure induced key reproductive PCOS traits of cycle irregularity and ovulatory dysfunction, and PCOS-like metabolic traits including increased body weight; white and brown fat pad weights; fasting serum triglyceride and glucose levels, and blood glucose incremental area under the curve. Treatment with a NK3R antagonist (MLE4901) did not impact the observed reproductive defects. In contrast, following NK3R antagonist treatment, PCOS-like females displayed decreased total body weight, adiposity, and adipocyte hypertrophy, but increased respiratory exchange ratio, suggesting NK3R antagonism altered the metabolic status of the PCOS-like females. NK3R antagonism did not improve circulating serum triglyceride or fasted glucose levels. Collectively, these findings demonstrate that NK3R antagonism may be beneficial in the treatment of adverse metabolic features associated with PCOS and support neuroendocrine targeting in the development of novel therapeutic strategies for PCOS.
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Affiliation(s)
- Irene E Sucquart
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Ruchi Nagarkar
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Melissa C Edwards
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Valentina Rodriguez Paris
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Ali Aflatounian
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Michael J Bertoldo
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Rebecca E Campbell
- Centre of Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Robert B Gilchrist
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
| | - Denovan P Begg
- Department of Behavioural Neuroscience, School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia
| | - David J Handelsman
- Andrology Laboratory, ANZAC Research Institute, University of Sydney, Concord Hospital, NSW 2139, Australia
| | | | - Richard A Anderson
- Medical Research Council Centre for Reproductive Health, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Kirsty A Walters
- Fertility and Research Centre, School of Women's & Children's Health, University of New South Wales, Sydney, NSW 2052, Australia
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Torres E, Velasco I, Franssen D, Heras V, Gaytan F, Leon S, Navarro VM, Pineda R, Candenas ML, Romero-Ruiz A, Tena-Sempere M. Congenital ablation of Tacr2 reveals overlapping and redundant roles of NK2R signaling in the control of reproductive axis. Am J Physiol Endocrinol Metab 2021; 320:E496-E511. [PMID: 33427049 PMCID: PMC8828271 DOI: 10.1152/ajpendo.00346.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tachykinin (TAC) signaling is an important element in the central control of reproduction. TAC family is mainly composed of substance P (SP), neurokinin A (NKA), and NKB, which bind preferentially to NK1, NK2, and NK3 receptors, respectively. While most studies have focused on the reproductive functions of NKB/NK3R, and to a lesser extent SP/NK1R, the relevance of NK2R, encoded by Tacr2, remains poorly characterized. Here, we address the physiological roles of NK2R in regulating the reproductive axis by characterizing a novel mouse line with congenital ablation of Tacr2. Activation of NK2R evoked acute luteinizing hormone (LH) responses in control mice, similar to those of agonists of NK1R and NK3R. Despite the absence of NK2R, Tacr2-/- mice displayed only partially reduced LH responses to an NK2R agonist, which, nonetheless, were abrogated after blockade of NK3R in Tacr2-/- males. While Tacr2-/- mice displayed normal pubertal timing, LH pulsatility was partially altered in Tacr2-/- females in adulthood, with suppression of basal LH levels, but no changes in the number of LH pulses. In addition, trends for increase in breeding intervals were detected in Tacr2-/- mice. However, null animals of both sexes were fertile, with no changes in estrous cyclicity or sex preference in social behavioral tests. In conclusion, stimulation of NK2R elicited LH responses in mice, while congenital ablation of Tacr2 partially suppressed basal and stimulated LH secretion, with moderate reproductive impact. Our data support a modest, albeit detectable, role of NK2R in the control of the gonadotropic axis, with partially overlapping and redundant functions with other tachykinin receptors.NEW & NOTEWORTHY We have explored here the impact of congenital ablation of the gene (Tacr2) encoding the tachykinin receptor, NK2R, in terms of neuroendocrine control of the reproductive axis, using a novel Tacr2 KO mouse line. Our data support a modest, albeit detectable, role of NK2R in the control of the gonadotropic axis, with partially overlapping and redundant functions with other tachykinin receptors.
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Affiliation(s)
- Encarnacion Torres
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - Inmaculada Velasco
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - Delphine Franssen
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - Violeta Heras
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - Francisco Gaytan
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - Silvia Leon
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
- Division of Endocrinology, Department of Medicine, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Victor M Navarro
- Division of Endocrinology, Department of Medicine, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Rafael Pineda
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - M Luz Candenas
- Instituto de Investigaciones Químicas, CSIC, Seville, Spain
| | - Antonio Romero-Ruiz
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, Instituto Maimonides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Córdoba, Spain
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine and Turku Center for Disease Modeling, University of Turku, Turku, Finland
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Lv Q, Zhong Z, Hu B, Yan S, Yan Y, Zhang J, Shi T, Jiang L, Li W, Huang W. MicroRNA-3473b regulates the expression of TREM2/ULK1 and inhibits autophagy in inflammatory pathogenesis of Parkinson disease. J Neurochem 2021; 157:599-610. [PMID: 33448372 DOI: 10.1111/jnc.15299] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 02/06/2023]
Abstract
Parkinson disease (PD) is a neurodegenerative disease characterized by selective loss of dopaminergic (DA) neurons in the midbrain. The regulatory role of a variety of microRNAs in PD has been confirmed, and our study is the first to demonstrate that miR-3473b is involved in the regulation of PD. In vitro, an miR-3473b inhibitor can inhibit the secretion of inflammatory factors (TNF-α and IL-1β) in moues microglia cell line (BV2) cells induced by lipopolysaccharide (LPS) and promote autophagy in BV2 cells. In vivo, miR-3473b antagomir can inhibit the activation of substantia nigra pars compacta (SNpc) microglia of C57BL/6 mice induced by 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and promote autophagy. Deletion of TREM2, one of the most highly expressed receptors in microglia, leads to the occurrence and development of PD. ULK1 is a component of the Atg1 complex. Deletion of ULK1 aggravates the pathological reaction of PD. TREM2 and ULK1 are predicted potential targets of miR-3473b by Targetscan. Then, the results of our experiments indicate that transfection with a miR-3473b mimic can inhibit the expression of TREM2 and ULK1. Data from a double luciferase experiment indicate that the 3'-UTR of TREM2, but not ULK1, is the direct target of miR-3473b. Then we aim to investigate the regulation of TREM2 and ULK1 in PD. We found that the expression of p-ULK1 was significantly increased via up-regulation of TREM2. The increased expression of p-ULK1 can promote autophagy and inhibit the expression of inflammatory factors. The regulation of ULK1 by miR-3473b may be accomplished indirectly through TREM2. Thus, miR-3473b may regulate the secretion of proinflammatory mediators by targeting TREM2/ULK1 expression to regulate the role of autophagy in the pathogenesis of inflammation in Parkinson's disease, suggesting that mir-3473b may be a potential therapeutic target to regulate the inflammatory response in PD.
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Affiliation(s)
- Qiankun Lv
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Zhen Zhong
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Binbin Hu
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Si Yan
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yufang Yan
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Junjun Zhang
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Ting Shi
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Lijuan Jiang
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Wen Li
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Wei Huang
- Department of Neurology, the Second Affiliated Hospital of Nanchang University, Nanchang, China
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44
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Bakker J. Kisspeptin and neurokinin B expression in the human hypothalamus: Relation to reproduction and gender identity. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:297-313. [PMID: 34225936 DOI: 10.1016/b978-0-12-820107-7.00018-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) neurons in the hypothalamus are at the core of reproductive functioning. GnRH released into the median eminence regulates the secretion of the gonadotropins from the anterior pituitary, which in turn activates gametogenesis and steroid synthesis by the gonads. The GnRH system displays functional sex differences: GnRH is secreted in pulses at a constant frequency in men, whereas in women, pulse frequency varies over the menstrual cycle. In both sexes, GnRH release is regulated by sex steroid hormones, acting at the level of the hypothalamus and the anterior pituitary in a classic feedback loop. Because GnRH neurons do not express sex steroid receptors, hormone effects on GnRH release are presumed to be mediated indirectly through other steroid-sensitive neuronal systems, which then converge onto GnRH cell bodies and/or terminals. Human genetic studies demonstrated that kisspeptin (KP) as well as neurokinin B (NKB) signaling are both potent regulators of GNRH secretion. In humans, postmortem studies using immunohistochemistry have shown that women have higher KP and NKB expression in the infundibular nucleus than men. Sex differences in KP expression are present throughout life, which is from the infant/prepubertal into the elderly period, whereas sex differences in NKB expression do not emerge until adulthood. KP and NKB are often coexpressed together with dynorphin by the same population of neurons, also known as KDNy neurons in other species. Indeed, significant coexpression between KP and NKB but not with Dynorphin has been observed thereby challenging the KDNy concept in humans. Female-typical expression of both KP and NKB were observed in the infundibular nucleus of trans women (male sex assigned at birth and female gender identity). Taken together, sex differences in KP and NKB expression most likely reflect organizational actions of sex steroid hormones on the developing brain but they also remain sensitive to circulating sex steroids in adulthood. The female-dominant sex difference in infundibular KP and NKB expression suggests that this brain region is most likely involved in both the negative and positive feedback actions of estrogens on GnRH secretion. Finally, the sex-reversal observed in KP and NKB expression in trans women might reflect, at least partially, an atypical sexual differentiation of the brain.
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Affiliation(s)
- Julie Bakker
- GIGA Neurosciences, Liège University, Liège, Belgium.
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Oghbaei H, Fattahi A, Hamidian G, Sadigh-Eteghad S, Ziaee M, Mahmoudi J. A closer look at the role of insulin for the regulation of male reproductive function. Gen Comp Endocrinol 2021; 300:113643. [PMID: 33017586 DOI: 10.1016/j.ygcen.2020.113643] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/16/2020] [Accepted: 09/28/2020] [Indexed: 11/25/2022]
Abstract
While insulin demonstrates to have a considerable influence on the reproductive system, there are various unanswered questions regarding its precise sites, mechanisms of action, and roles for the developing and functioning of the adult male reproductive system. Apart from its effects on glucose level, insulin has an important role in the reproductive system directly by binding on insulin and IGF receptors in the brain and testis. To date, however, the effect of insulin or its alterations on blood-testis-barrier, as an important regulator of normal spermatogenesis and fertility, has not yet been studied. This review aimed to focus on the experimental and clinical studies to describe mechanisms by which insulin affects the hypothalamic-pituitary-gonadal (HPG) axis, testicular cells, spermatozoa, and sexual behavior. Moreover, we discussed the mechanism and impact of insulin changes in type 1 (insulin deficiency along with persisted or even increased sensitivity) and 2 (insulin resistance along with increased insulin level at the early stages of disease) diabetes and obesity on the male reproductive tract.
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Affiliation(s)
- Hajar Oghbaei
- Department of Physiology, Tabriz University of Medical Sciences, Tabriz, Iran; Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Fattahi
- Department of Reproductive Biology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - GholamReza Hamidian
- Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Saeed Sadigh-Eteghad
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mojtaba Ziaee
- Medicinal Plants Research Center, Maragheh University of Medical Sciences, Maragheh, Iran
| | - Javad Mahmoudi
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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46
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Rumpler É, Skrapits K, Takács S, Göcz B, Trinh SH, Rácz G, Matolcsy A, Kozma Z, Ciofi P, Dhillo WS, Hrabovszky E. Characterization of Kisspeptin Neurons in the Human Rostral Hypothalamus. Neuroendocrinology 2021; 111:249-262. [PMID: 32299085 DOI: 10.1159/000507891] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/14/2020] [Indexed: 11/19/2022]
Abstract
BACKGROUND Kisspeptin (KP) neurons in the rostral periventricular region of the 3rd ventricle (RP3V) of female rodents mediate positive estrogen feedback to gonadotropin-releasing hormone neurons and, thus, play a fundamental role in the mid-cycle luteinizing hormone (LH) surge. The RP3V is sexually dimorphic, and male rodents with lower KP cell numbers are unable to mount estrogen-induced LH surges. OBJECTIVE To find and characterize the homologous KP neurons in the human brain, we studied formalin-fixed post-mortem hypothalami. METHODS Immunohistochemical techniques were used. RESULTS The distribution of KP neurons in the rostral hypothalamus overlapped with distinct subdivisions of the paraventricular nucleus. The cell numbers decreased after menopause, indicating that estrogens positively regulate KP gene expression in the rostral hypothalamus in humans, similarly to several other species. Young adult women and men had similar cell numbers, as opposed to rodents reported to have more KP neurons in the RP3V of females. Human KP neurons differed from the homologous rodent cells as well, in that they were devoid of enkephalins, galanin and tyrosine hydroxylase. Further, they did not contain known KP neuron markers of the human infundibular nucleus, neurokinin B, substance P and cocaine- and amphetamine-regulated transcript, while they received afferent input from these KP neurons. CONCLUSIONS The identification and positive estrogenic regulation of KP neurons in the human rostral hypothalamus challenge the long-held view that positive estrogen feedback may be restricted to the mediobasal part of the hypothalamus in primates and point to the need of further anatomical, molecular and functional studies of rostral hypothalamic KP neurons.
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Affiliation(s)
- Éva Rumpler
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Katalin Skrapits
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Szabolcs Takács
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Balázs Göcz
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Sarolta H Trinh
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Gergely Rácz
- 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - András Matolcsy
- 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Zsolt Kozma
- Department of Forensic Medicine, Faculty of Medicine, University of Pécs, Pécs, Hungary
| | | | - Waljit S Dhillo
- Department of Investigative Medicine, Hammersmith Hospital, Imperial College London, London, United Kingdom
| | - Erik Hrabovszky
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary,
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Abstract
Puberty, which in humans is considered to include both gonadarche and adrenarche, is the period of becoming capable of reproducing sexually and is recognized by maturation of the gonads and development of secondary sex characteristics. Gonadarche referring to growth and maturation of the gonads is fundamental to puberty since it encompasses increased gonadal steroid secretion and initiation of gametogenesis resulting from enhanced pituitary gonadotropin secretion, triggered in turn by robust pulsatile GnRH release from the hypothalamus. This chapter reviews the development of GnRH pulsatility from before birth until the onset of puberty. In humans, GnRH pulse generation is restrained during childhood and juvenile development. This prepubertal hiatus in hypothalamic activity is considered to result from a neurobiological brake imposed upon the GnRH pulse generator resident in the infundibular nucleus. Reactivation of the GnRH pulse generator initiates pubertal development. Current understanding of the genetics and physiology of the brake will be discussed, as will hypotheses proposed to account for timing the resurgence in pulsatile GnRH and initiation of puberty. The chapter ends with a discussion of disorders associated with precocious or delayed puberty with a focus on those with etiologies attributed to aberrant GnRH neuron anatomy or function. A pediatric approach to patients with pubertal disorders is provided and contemporary treatments for both precocious and delayed puberty outlined.
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Affiliation(s)
- Selma Feldman Witchel
- Pediatric Endocrinology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, United States.
| | - Tony M Plant
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, United States
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48
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Wu HM, Chang HM, Leung PCK. Gonadotropin-releasing hormone analogs: Mechanisms of action and clinical applications in female reproduction. Front Neuroendocrinol 2021; 60:100876. [PMID: 33045257 DOI: 10.1016/j.yfrne.2020.100876] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/23/2020] [Accepted: 10/04/2020] [Indexed: 12/15/2022]
Abstract
Extra-hypothalamic GnRH and extra-pituitary GnRH receptors exist in multiple human reproductive tissues, including the ovary, endometrium and myometrium. Recently, new analogs (agonists and antagonists) and modes of GnRH have been developed for clinical application during controlled ovarian hyperstimulation for assisted reproductive technology (ART). Additionally, the analogs and upstream regulators of GnRH suppress gonadotropin secretion and regulate the functions of the reproductive axis. GnRH signaling is primarily involved in the direct control of female reproduction. The cellular mechanisms and action of the GnRH/GnRH receptor system have been clinically applied for the treatment of reproductive disorders and have widely been introduced in ART. New GnRH analogs, such as long-acting GnRH analogs and oral nonpeptide GnRH antagonists, are being continuously developed for clinical application. The identification of the upstream regulators of GnRH, such as kisspeptin and neurokinin B, provides promising potential to develop these upstream regulator-related analogs to control the hypothalamus-pituitary-ovarian axis.
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Affiliation(s)
- Hsien-Ming Wu
- Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Linkou Medical Center, Chang Gung University School of Medicine, Taoyuan 333, Taiwan, ROC
| | - Hsun-Ming Chang
- Department of Obstetrics and Gynaecology, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, British Columbia V6H 3V5, Canada
| | - Peter C K Leung
- Department of Obstetrics and Gynaecology, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, British Columbia V6H 3V5, Canada.
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Hrabovszky E, Takács S, Rumpler É, Skrapits K. The human hypothalamic kisspeptin system: Functional neuroanatomy and clinical perspectives. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:275-296. [PMID: 34225935 DOI: 10.1016/b978-0-12-820107-7.00017-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In mammals, kisspeptin neurons are the key components of the hypothalamic neuronal networks that regulate the onset of puberty, account for the pulsatile secretion of gonadotropin-releasing hormone (GnRH) and mediate negative and positive estrogen feedback signals to GnRH neurons. Being directly connected anatomically and functionally to the hypophysiotropic GnRH system, the major kisspeptin cell groups of the preoptic area/rostral hypothalamus and the arcuate (or infundibular) nucleus, respectively, are ideally positioned to serve as key nodes which integrate various types of environmental, endocrine, and metabolic signals that can influence fertility. This chapter provides an overview of the current state of knowledge on the anatomy, functions, and plasticity of brain kisspeptin systems based on the wide literature available from different laboratory and domestic species. Then, the species-specific features of human hypothalamic kisspeptin neurons are described, covering their topography, morphology, unique neuropeptide content, plasticity, and connectivity to hypophysiotropic GnRH neurons. Some newly emerging roles of central kisspeptin signaling in behavior and finally, clinical perspectives, are discussed.
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Affiliation(s)
- Erik Hrabovszky
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary.
| | - Szabolcs Takács
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Éva Rumpler
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Katalin Skrapits
- Laboratory of Reproductive Neurobiology, Institute of Experimental Medicine, Budapest, Hungary
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50
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Liao B, Qiao J, Pang Y. Central Regulation of PCOS: Abnormal Neuronal-Reproductive-Metabolic Circuits in PCOS Pathophysiology. Front Endocrinol (Lausanne) 2021; 12:667422. [PMID: 34122341 PMCID: PMC8194358 DOI: 10.3389/fendo.2021.667422] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 05/07/2021] [Indexed: 12/13/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disease. PCOS patients are characterized by hyperandrogenemia, anovulation, and metabolic dysfunction. Hypothalamus-pituitary-ovary axis imbalance is considered as an important pathophysiology underlying PCOS, indicating that central modulation, especially the abnormal activation of hypothalamic GnRH neurons plays a vital role in PCOS development. Increased GnRH pulse frequency can promote LH secretion, leading to ovarian dysfunction and abnormal sex steroids synthesis. By contrast, peripheral sex steroids can modulate the action of GnRH neurons through a feedback effect, which is impaired in PCOS, thus forming a vicious cycle. Additionally, hypothalamic GnRH neurons not only serve as the final output pathway of central control of reproductive axis, but also as the central connection point where reproductive function and metabolic state inter-regulate with each other. Metabolic factors, such as insulin resistance and obesity in PCOS patients can regulate GnRH neurons activity, and ultimately regulate reproductive function. Besides, gut hormones act on both brain and peripheral organs to modify metabolic state. Gut microbiota disturbance is also related to many metabolic diseases and has been reported to play an essential part in PCOS development. This review concludes with the mechanism of central modulation and the interaction between neuroendocrine factors and reproductive or metabolic disorders in PCOS development. Furthermore, the role of the gut microenvironment as an important part involved in the abnormal neuronal-reproductive-metabolic circuits that contribute to PCOS is discussed, thus offering possible central and peripheral therapeutic targets for PCOS patients.
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Affiliation(s)
- Baoying Liao
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- National Clinical Research Center for Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Peking University Third Hospital, Beijing, China
| | - Jie Qiao
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- National Clinical Research Center for Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Peking University Third Hospital, Beijing, China
| | - Yanli Pang
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- National Clinical Research Center for Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Peking University Third Hospital, Beijing, China
- *Correspondence: Yanli Pang,
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