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Rabconnectin-3α is required for the morphological maturation of GnRH neurons and kisspeptin responsiveness. Sci Rep 2017; 7:42463. [PMID: 28209974 PMCID: PMC5314327 DOI: 10.1038/srep42463] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 01/11/2017] [Indexed: 12/18/2022] Open
Abstract
A few hundred hypothalamic neurons form a complex network that controls reproduction in mammals by secreting gonadotropin-releasing hormone (GnRH). Timely postnatal changes in GnRH secretion are essential for pubertal onset. During the juvenile period, GnRH neurons undergo morphological remodeling, concomitantly achieving an increased responsiveness to kisspeptin, the main secretagogue of GnRH. However, the link between GnRH neuron activity and their morphology remains unknown. Here, we show that brain expression levels of Dmxl2, which encodes the vesicular protein rabconnectin-3α, determine the capacity of GnRH neurons to be activated by kisspeptin and estradiol. We also demonstrate that Dmxl2 expression levels control the pruning of GnRH dendrites, highlighting an unexpected role for a vesicular protein in the maturation of GnRH neuronal network. This effect is mediated by rabconnectin-3α in neurons or glial cells afferent to GnRH neurons. The widespread expression of Dmxl2 in several brain areas raises the intriguing hypothesis that rabconnectin-3α could be involved in the maturation of other neuronal populations.
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Evans MC, Anderson GM. Neuroendocrine integration of nutritional signals on reproduction. J Mol Endocrinol 2017; 58:R107-R128. [PMID: 28057770 DOI: 10.1530/jme-16-0212] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 12/28/2022]
Abstract
Reproductive function in mammals is energetically costly and therefore tightly regulated by nutritional status. To enable this integration of metabolic and reproductive function, information regarding peripheral nutritional status must be relayed centrally to the gonadotropin-releasing hormone (GNRH) neurons that drive reproductive function. The metabolically relevant hormones leptin, insulin and ghrelin have been identified as key mediators of this 'metabolic control of fertility'. However, the neural circuitry through which they act to exert their control over GNRH drive remains incompletely understood. With the advent of Cre-LoxP technology, it has become possible to perform targeted gene-deletion and gene-rescue experiments and thus test the functional requirement and sufficiency, respectively, of discrete hormone-neuron signaling pathways in the metabolic control of reproductive function. This review discusses the findings from these investigations, and attempts to put them in context with what is known from clinical situations and wild-type animal models. What emerges from this discussion is clear evidence that the integration of nutritional signals on reproduction is complex and highly redundant, and therefore, surprisingly difficult to perturb. Consequently, the deletion of individual hormone-neuron signaling pathways often fails to cause reproductive phenotypes, despite strong evidence that the targeted pathway plays a role under normal physiological conditions. Although transgenic studies rarely reveal a critical role for discrete signaling pathways, they nevertheless prove to be a good strategy for identifying whether a targeted pathway is absolutely required, critically involved, sufficient or dispensable in the metabolic control of fertility.
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Affiliation(s)
- Maggie C Evans
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago School of Medical Sciences, Dunedin, New Zealand
| | - Greg M Anderson
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago School of Medical Sciences, Dunedin, New Zealand
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Hu KL, Zhao H, Chang HM, Yu Y, Qiao J. Kisspeptin/Kisspeptin Receptor System in the Ovary. Front Endocrinol (Lausanne) 2017; 8:365. [PMID: 29354093 PMCID: PMC5758547 DOI: 10.3389/fendo.2017.00365] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/13/2017] [Indexed: 12/26/2022] Open
Abstract
Kisspeptins are a family of neuropeptides that are critical for initiating puberty and regulating ovulation in sexually mature females via the central control of the hypothalamic-pituitary-gonadal axis. Recent studies have shown that kisspeptin and its receptor kisspeptin receptor (KISS1R) are expressed in the mammalian ovary. Convincing evidence indicates that kisspeptins can activate a wide variety of signals via its binding to KISS1R. Experimental data gathered recently suggest a putative role of kisspeptin signaling in the direct control of ovarian function, including follicular development, oocyte maturation, steroidogenesis, and ovulation. Dysregulation or naturally occurring mutations of the kisspeptin/KISS1R system may negatively affect the ovarian function, leading to reproductive pathology or female infertility. A comprehensive understanding of the expression, actions, and underlying molecular mechanisms of this system in the human ovary is essential for novel approaches to therapeutic and diagnostic interventions in reproductive diseases and infertility.
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Affiliation(s)
- Kai-Lun Hu
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology and Key Laboratory of Assisted Reproduction, Ministry of Education, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
| | - Hongcui Zhao
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology and Key Laboratory of Assisted Reproduction, Ministry of Education, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- *Correspondence: Hongcui Zhao, ; Yang Yu,
| | - Hsun-Ming Chang
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology and Key Laboratory of Assisted Reproduction, Ministry of Education, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
| | - Yang Yu
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology and Key Laboratory of Assisted Reproduction, Ministry of Education, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
- *Correspondence: Hongcui Zhao, ; Yang Yu,
| | - Jie Qiao
- Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology and Key Laboratory of Assisted Reproduction, Ministry of Education, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China
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Abstract
Kisspeptins are a group of peptide fragments encoded by the KISS1 gene in humans. They bind to kisspeptin receptors with equal efficacy. Kisspeptins and their receptors are expressed by neurons in the arcuate and anteroventral periventricular nuclei of the hypothalamus. Oestrogen mediates negative feedback of gonadotrophin-releasing hormone secretion via the arcuate nucleus. Conversely, it exerts positive feedback via the anteroventral periventricular nucleus. The sexual dimorphism of these nuclei accounts for the differential behaviour of the hypothalamic-pituitary-gonadal axis between genders. Kisspeptins are essential for reproductive function. Puberty is regulated by the maturation of kisspeptin neurons and by interactions between kisspeptins and leptin. Hence, kisspeptins have potential diagnostic and therapeutic applications. Kisspeptin agonists may be used to localise lesions in cases of hypothalamic-pituitary-gonadal axis dysfunction and evaluate the gonadotrophic potential of subfertile individuals. Kisspeptin antagonists may be useful as contraceptives in women, through the prevention of premature luteinisation during in vitro fertilisation, and in the treatment of sex steroid-dependent diseases and metastatic cancers.
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Affiliation(s)
- Eng Loon Tng
- Associate Consultant, Department of Medicine, Ng Teng Fong General Hospital, 1 Jurong East Street 21, Singapore 609606
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55
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Fergani C, Mazzella L, Coolen LM, McCosh RB, Hardy SL, Newcomb N, Grachev P, Lehman MN, Goodman RL. Do Substance P and Neurokinin A Play Important Roles in the Control of LH Secretion in Ewes? Endocrinology 2016; 157:4829-4841. [PMID: 27704950 PMCID: PMC5133348 DOI: 10.1210/en.2016-1565] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
There is now general agreement that neurokinin B (NKB) acts via neurokinin-3-receptor (NK3R) to stimulate secretion of GnRH and LH in several species, including rats, mice, sheep, and humans. However, the roles of two other tachykinins, substance P (SP) and neurokinin A, which act primarily via NK1R and NK2R, respectively, are less clear. In rodents, these signaling pathways can stimulate LH release and substitute for NKB signaling; in humans, SP is colocalized with kisspeptin and NKB in the mediobasal hypothalamus. In this study, we examined the possible role of these tachykinins in control of the reproductive axis in sheep. Immunohistochemistry was used to describe the expression of SP and NK1R in the ovine diencephalon and determine whether these proteins are colocalized in kisspeptin or GnRH neurons. SP-containing cell bodies were largely confined to the arcuate nucleus, but NK1R-immunoreactivity was more widespread. However, there was very low coexpression of SP or NK1R in kisspeptin cells and none in GnRH neurons. We next determined the minimal effective dose of these three tachykinins that would stimulate LH secretion when administered into the third ventricle of ovary-intact anestrous sheep. A much lower dose of NKB (0.2 nmol) than of neurokinin A (2 nmol) or SP (10 nmol) consistently stimulated LH secretion. Moreover, the relative potency of these three neuropeptides parallels the relative selectivity of NK3R. Based on these anatomical and pharmacological data, we conclude that NKB-NK3R signaling is the primary pathway for the control of GnRH secretion by tachykinins in ewes.
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Affiliation(s)
- Chrysanthi Fergani
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Leanne Mazzella
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Lique M Coolen
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Richard B McCosh
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Steven L Hardy
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Nora Newcomb
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Pasha Grachev
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Michael N Lehman
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
| | - Robert L Goodman
- Departments of Neurobiology and Anatomical Sciences (C.F., M.N.L.) and Physiology (L.M.C., N.N.), University of Mississippi Medical Center, Jackson, Mississippi 39216-4505; and Department of Physiology and Pharmacology (L.M., R.B.M., S.L.H., P.G., R.L.G.), West Virginia University Health Sciences Center, Morgantown, West Virginia 26506-9229
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56
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Skorupskaite K, George JT, Veldhuis JD, Millar RP, Anderson RA. Interactions Between Neurokinin B and Kisspeptin in Mediating Estrogen Feedback in Healthy Women. J Clin Endocrinol Metab 2016; 101:4628-4636. [PMID: 27636018 PMCID: PMC5155690 DOI: 10.1210/jc.2016-2132] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Kisspeptin and neurokinin B (NKB) are obligate for normal gonadotropin secretion, but their hierarchy is unexplored in normal women. OBJECTIVE To investigate the interaction between kisspeptin and NKB on estrogen-regulated LH secretion. DESIGN Women were treated with neurokinin-3 receptor (NK3R) antagonist followed by transdermal estradiol to induce LH secretion 48 hours later, with kisspeptin-10 or vehicle infusion during estrogen administration in a 2-way crossover study. SETTING Clinical research facility. PATIENTS OR OTHER PARTICIPANTS Healthy females with regular menses. INTERVENTION(S) NK3R antagonist AZD4901 40 mg twice daily orally was taken from cycle day 4-6 for 6 days (n = 10, with 10 no treatment controls). Transdermal estradiol patches (200 μg/d) were applied after 5 days of NK3R antagonist treatment. At 24-hour estradiol treatment, women were randomized to 7-hour kisspeptin-10 (4 μg/kg/h) or vehicle iv infusion, with the alternate infusion in a subsequent cycle. MAIN OUTCOME MEASURE(S) Plasma gonadotropin and estradiol secretion. RESULTS After an initial suppression, LH secretion was increased 48 hours after estradiol treatment. Kisspeptin-10 increased LH secretion during the inhibitory phase, and LH remained elevated beyond the discontinuation of kisspeptin-10 infusion. NK3R antagonist decreased LH pulse frequency (0.5 ± 0.2 vs 0.7 ± 0.2 pulses/h, P < .05) and stimulated FSH response to kisspeptin-10 infusion (10.7 ± 11.0 vs 5.0 ± 3.6 IU/L, P < .05) with a nonsignificant rise in LH. The duration of LH response was blunted, with LH being lower at 48 hours (7.5 ± 4.8 vs 15.0 ± 11.4 IU/L, P < .05). CONCLUSIONS These data demonstrate that NKB signaling regulates GnRH/LH secretion in normal women, and is predominantly proximal to kisspeptin in mediating estrogenic positive and negative feedback on LH secretion.
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Affiliation(s)
- Karolina Skorupskaite
- MRC Centre for Reproductive Health (K.S., J.T.G., R.A.A.), The Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom; Endocrine Research Unit (J.D.V.), Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905; and Mammal Research Unit and Centre for Neuroendocrinology (R.P.M.), University of Pretoria, 0028 Pretoria, South Africa and MRC Receptor Biology Unit, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, 7925 Observatory, South Africa
| | - Jyothis T George
- MRC Centre for Reproductive Health (K.S., J.T.G., R.A.A.), The Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom; Endocrine Research Unit (J.D.V.), Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905; and Mammal Research Unit and Centre for Neuroendocrinology (R.P.M.), University of Pretoria, 0028 Pretoria, South Africa and MRC Receptor Biology Unit, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, 7925 Observatory, South Africa
| | - Johannes D Veldhuis
- MRC Centre for Reproductive Health (K.S., J.T.G., R.A.A.), The Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom; Endocrine Research Unit (J.D.V.), Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905; and Mammal Research Unit and Centre for Neuroendocrinology (R.P.M.), University of Pretoria, 0028 Pretoria, South Africa and MRC Receptor Biology Unit, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, 7925 Observatory, South Africa
| | - Robert P Millar
- MRC Centre for Reproductive Health (K.S., J.T.G., R.A.A.), The Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom; Endocrine Research Unit (J.D.V.), Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905; and Mammal Research Unit and Centre for Neuroendocrinology (R.P.M.), University of Pretoria, 0028 Pretoria, South Africa and MRC Receptor Biology Unit, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, 7925 Observatory, South Africa
| | - Richard A Anderson
- MRC Centre for Reproductive Health (K.S., J.T.G., R.A.A.), The Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, United Kingdom; Endocrine Research Unit (J.D.V.), Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905; and Mammal Research Unit and Centre for Neuroendocrinology (R.P.M.), University of Pretoria, 0028 Pretoria, South Africa and MRC Receptor Biology Unit, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, 7925 Observatory, South Africa
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57
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Lopez JA, Bedenbaugh MN, McCosh RB, Weems PW, Meadows LJ, Wisman B, Coolen LM, Goodman RL, Hileman SM. Does Dynorphin Play a Role in the Onset of Puberty in Female Sheep? J Neuroendocrinol 2016; 28:10.1111/jne.12445. [PMID: 28328155 PMCID: PMC5412962 DOI: 10.1111/jne.12445] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 10/05/2016] [Accepted: 11/01/2016] [Indexed: 11/30/2022]
Abstract
Puberty onset involves increased gonadotrophin-release (GnRH) release as a result of decreased sensitivity to oestrogen (E2 )-negative feedback. Because GnRH neurones lack E2 receptor α, this pathway must contain interneurones. One likely candidate is KNDy neurones (kisspeptin, neurokinin B, dynorphin). The overarching hypothesis of the present study was that the prepubertal hiatus in luteinising hormone (LH) release involves reduced kisspeptin and/or heightened dynorphin input. We first tested the specific hypothesis that E2 would reduce kisspeptin-immunopositive cell numbers and increase dynorphin-immunopositive cell numbers. We found that kisspeptin cell numbers were higher in ovariectomised (OVX) lambs than OVX lambs treated with E2 (OVX+ E2 ) or those left ovary-intact. Very few arcuate dynorphin cells were identified in any group. Next, we hypothesised that central blockade of κ-opioid receptor (KOR) would increase LH secretion at a prepubertal (6 months) but not postpubertal (10 months) age. Luteinising hormone pulse frequency and mean LH increased during infusion of a KOR antagonist, norbinaltorphimine, in OVX + E2 lambs at the prepubertal age but not in the same lambs at the postpubertal age. We next hypothesised that E2 would increase KOR expression in GnRH neurones or alter synaptic input to KNDy neurones in prepubertal ewes. Oestrogen treatment decreased the percentage of GnRH neurones coexpressing KOR (approximately 68%) compared to OVX alone (approximately 78%). No significant differences in synaptic contacts per cell between OVX and OVX + E2 groups were observed. Although these initial data are consistent with dynorphin inhibiting pulsatile LH release prepubertally, additional work will be necessary to define the source and mechanisms of this inhibition.
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Affiliation(s)
- J A Lopez
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - M N Bedenbaugh
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - R B McCosh
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - P W Weems
- Department of Neurobiology and Anatomical Sciences, The University of Mississippi Medical Center, Jackson, MS, USA
| | - L J Meadows
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - B Wisman
- Department of Biology, Alderson-Broaddus University, Philippi, WV, USA
| | - L M Coolen
- Department of Neurobiology and Anatomical Sciences, The University of Mississippi Medical Center, Jackson, MS, USA
| | - R L Goodman
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - S M Hileman
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
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58
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Fergani C, Navarro VM. Expanding the Role of Tachykinins in the Neuroendocrine Control of Reproduction. Reproduction 2016; 153:R1-R14. [PMID: 27754872 DOI: 10.1530/rep-16-0378] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/17/2016] [Indexed: 11/08/2022]
Abstract
Reproductive function is driven by the hormonal interplay between the gonads and brain-pituitary axis. Gonadotropin-releasing hormone (GnRH) is released in a pulsatile manner, which is critical for the attainment and maintenance of fertility, however, GnRH neurons lack the ability to directly respond to most regulatory factors, and a hierarchical upstream neuronal network governs its secretion. We and others proposed a model in which Kiss1 neurons in the arcuate nucleus (ARC), so called KNDy neurons, release kisspeptin (a potent GnRH secretagogue) in a pulsatile manner to drive GnRH pulses under the coordinated autosynaptic action of its cotransmitters, the tachykinin neurokinin B (NKB, stimulatory) and dynorphin (inhibitory). Numerous genetic and pharmacological studies support this model; however, additional regulatory mechanisms (upstream of KNDy neurons) and alternative pathways of GnRH secretion (kisspeptin-independent) exist, but remain ill defined. In this aspect, attention to other members of the tachykinin family, namely substance P (SP) and neurokinin A (NKA), has recently been rekindled. Even though there are still major gaps in our knowledge about the functional significance of these systems, substantial evidence, as discussed below, is placing tachykinin signaling as an important pathway for the awakening of the reproductive axis and the onset of puberty to physiological GnRH secretion and maintenance of fertility in adulthood.
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Affiliation(s)
- Chrysanthi Fergani
- C Fergani, Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Boston, 02115, United States
| | - Victor M Navarro
- V Navarro, Endocrinology, Diabetes and Hypertension, Brigham and Women\'s Hospital, Boston, United States
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Kim JS. What's in a Name? Roles of RFamide-Related Peptides Beyond Gonadotrophin Inhibition. J Neuroendocrinol 2016; 28. [PMID: 27369805 DOI: 10.1111/jne.12407] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/21/2016] [Accepted: 06/23/2016] [Indexed: 12/29/2022]
Abstract
RFamide-related peptides (RFRPs) have been heavily implicated in the control of reproductive function subsequent to their discovery more than 16 years ago. However, recent studies using genetic and pharmacological tools have challenged their importance in regulating the hypothalamic-pituitary-gonadal axis. It is generally accepted that RFRPs act as part of a wider RFamide system, which involves two receptors, called the neuropeptide FF receptors (NPFFR1 and R2), and includes the closely-related neuropeptide NPFF. NPFF has been studied ever since the 1980s and many of the functions of NPFF are also shared by RFRPs. The current review questions whether these functions of NPFF are indeed specific to just NPFF alone and presents evidence from both neuroendocrine and pharmacological perspectives. Furthermore, recently emerging new functions of RFRPs are discussed with the overall goal of clarifying the functions of RFRPs beyond the hypothalamic-pituitary-gonadal axis.
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Affiliation(s)
- J S Kim
- Centre for Neuroendocrinology and Department of Anatomy, University of Otago, Dunedin, New Zealand
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60
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Qi X, Salem M, Zhou W, Sato-Shimizu M, Ye G, Smitz J, Peng C. Neurokinin B Exerts Direct Effects on the Ovary to Stimulate Estradiol Production. Endocrinology 2016; 157:3355-65. [PMID: 27580802 DOI: 10.1210/en.2016-1354] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurokinin B (NKB) and its receptor, NK3R, play critical roles in reproduction by regulating the secretion of the hypothalamic GnRH. NKB and NK3R genes are also expressed in the ovary; however, their physiological roles within the ovary are unknown. The aim of this study was to determine whether NKB acts directly on the ovary to regulate reproduction. Injection of NKB into zebrafish accelerated follicle development, increased the mRNA levels of cyp11a1 and cyp19a1, and enhanced estradiol production. Similarly, NKB induced cyp11a1 and cyp19a1 expression in primary cultures of zebrafish follicular cells and stimulated estradiol production from cultured follicles. Furthermore, NKB activates cAMP response element-binding protein and ERK, and ERK inhibitors abolished the effect of NKB on cyp11a1, whereas protein kinase A and calmodulin-dependent protein kinase II inhibitors that blocked the activation of cAMP response element-binding protein, attenuated the effect of NKB on cyp19a1 expression. In a human granulosa cell line, COV434, a NKB agonist, senktide, also increased CYP11A1 and CYP19A1 mRNA levels and enhanced aromatase protein levels and activities. Small interfering RNA-mediated knockdown of NK3R reduced senktide-induced CYP11A1 and CYP19A1 mRNA levels. Finally, we found that NK3R mRNA was strongly down-regulated in granulosa cells obtained from polycystic ovary syndrome (PCOS) patients when compared with non-PCOS subjects. Taken together, our findings establish a direct action of NKB to induce ovarian estrogen production and raise the possibility that defective signaling of this pathway may contribute to the development of PCOS.
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Affiliation(s)
- Xin Qi
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
| | - Mohamed Salem
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
| | - Wenyi Zhou
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
| | - Miwa Sato-Shimizu
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
| | - Gang Ye
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
| | - Johan Smitz
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
| | - Chun Peng
- Department of Biology (X.Q., M.S., W.Z., G.Y., C.P.), York University, Toronto, Ontario, Canada M3J 1P3; and Follicle Biology Laboratory (M.S.S., J.S.), Free University of Brussels Vrije Universiteit Brussel, 1090 Brussel, Belgium
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Manfredi-Lozano M, Roa J, Ruiz-Pino F, Piet R, Garcia-Galiano D, Pineda R, Zamora A, Leon S, Sanchez-Garrido MA, Romero-Ruiz A, Dieguez C, Vazquez MJ, Herbison AE, Pinilla L, Tena-Sempere M. Defining a novel leptin-melanocortin-kisspeptin pathway involved in the metabolic control of puberty. Mol Metab 2016; 5:844-857. [PMID: 27688998 PMCID: PMC5034608 DOI: 10.1016/j.molmet.2016.08.003] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/02/2016] [Accepted: 08/05/2016] [Indexed: 11/24/2022] Open
Abstract
Objective Puberty is a key developmental phenomenon highly sensitive to metabolic modulation. Worrying trends of changes in the timing of puberty have been reported in humans. These might be linked to the escalating prevalence of childhood obesity and could have deleterious impacts on later (cardio-metabolic) health, but their underlying mechanisms remain unsolved. The neuropeptide α-MSH, made by POMC neurons, plays a key role in energy homeostasis by mediating the actions of leptin and likely participates in the control of reproduction. However, its role in the metabolic regulation of puberty and interplay with kisspeptin, an essential puberty-regulating neuropeptide encoded by Kiss1, remain largely unknown. We aim here to unveil the potential contribution of central α-MSH signaling in the metabolic control of puberty by addressing its role in mediating the pubertal effects of leptin and its potential interaction with kisspeptin. Methods Using wild type and genetically modified rodent models, we implemented pharmacological studies, expression analyses, electrophysiological recordings, and virogenetic approaches involving DREADD technology to selectively inhibit Kiss1 neurons, in order to interrogate the physiological role of a putative leptin→α-MSH→kisspeptin pathway in the metabolic control of puberty. Results Stimulation of central α-MSH signaling robustly activated the reproductive axis in pubertal rats, whereas chronic inhibition of melanocortin receptors MC3/4R, delayed puberty, and prevented the permissive effect of leptin on puberty onset. Central blockade of MC3/4R or genetic elimination of kisspeptin receptors from POMC neurons did not affect kisspeptin effects. Conversely, congenital ablation of kisspeptin receptors or inducible, DREADD-mediated inhibition of arcuate nucleus (ARC) Kiss1 neurons resulted in markedly attenuated gonadotropic responses to MC3/4R activation. Furthermore, close appositions were observed between POMC fibers and ARC Kiss1 neurons while blockade of α-MSH signaling suppressed Kiss1 expression in the ARC of pubertal rats. Conclusions Our physiological, virogenetic, and functional genomic studies document a novel α-MSH→kisspeptin→GnRH neuronal signaling pathway involved in transmitting the permissive effects of leptin on pubertal maturation, which is relevant for the metabolic (and, eventually, pharmacological) regulation of puberty onset. Puberty is highly sensitive to metabolic modulation and disturbed by child obesity. Altered puberty is linked to adverse metabolic health outcomes via unclear mechanisms. The POMC product, α-MSH, transmit leptin-mediated metabolic regulation of puberty. A novel α-MSH→kisspeptin→GnRH signaling pathway is involved in the control of puberty This pathway is important for the metabolic (and pharmacologic) control of puberty.
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Affiliation(s)
- Maria Manfredi-Lozano
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain
| | - Juan Roa
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain.
| | - Francisco Ruiz-Pino
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Richard Piet
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, 9054 Dunedin, New Zealand
| | - David Garcia-Galiano
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain
| | - Rafael Pineda
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain
| | - Aurora Zamora
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain
| | - Silvia Leon
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain
| | - Miguel A Sanchez-Garrido
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Antonio Romero-Ruiz
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain
| | - Carlos Dieguez
- Department of Physiology, CIMUS, University of Santiago de Compostela, Santiago de Compostela 15782, Spain
| | - Maria Jesus Vazquez
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Allan E Herbison
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, 9054 Dunedin, New Zealand
| | - Leonor Pinilla
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Manuel Tena-Sempere
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain.
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Grachev P, Porter KL, Coolen LM, McCosh RB, Connors JM, Hileman SM, Lehman MN, Goodman RL. Surge-Like Luteinising Hormone Secretion Induced by Retrochiasmatic Area NK3R Activation is Mediated Primarily by Arcuate Kisspeptin Neurones in the Ewe. J Neuroendocrinol 2016; 28:10.1111/jne.12393. [PMID: 27059932 PMCID: PMC5157122 DOI: 10.1111/jne.12393] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/17/2016] [Accepted: 04/04/2016] [Indexed: 01/17/2023]
Abstract
The neuropeptides neurokinin B (NKB) and kisspeptin are potent stimulators of gonadotrophin-releasing hormone (GnRH)/luteinsing hormone (LH) secretion and are essential for human fertility. We have recently demonstrated that selective activation of NKB receptors (NK3R) within the retrochiasmatic area (RCh) and the preoptic area (POA) triggers surge-like LH secretion in ovary-intact ewes, whereas blockade of RCh NK3R suppresses oestradiol-induced LH surges in ovariectomised ewes. Although these data suggest that NKB signalling within these regions of the hypothalamus mediates the positive-feedback effects of oestradiol on LH secretion, the pathway through which it stimulates GnRH/LH secretion remains unclear. We proposed that the action of NKB on RCh neurones drives the LH surge by stimulating kisspeptin-induced GnRH secretion. To test this hypothesis, we quantified the activation of the preoptic/hypothalamic populations of kisspeptin neurones in response to POA or RCh administration of senktide by dual-label immunohistochemical detection of kisspeptin and c-Fos (i.e. marker of neuronal activation). We then administered the NK3R agonist, senktide, into the RCh of ewes in the follicular phase of the oestrous cycle and conducted frequent blood sampling during intracerebroventricular infusion of the kisspeptin receptor antagonist Kp-271 or saline. Our results show that the surge-like secretion of LH induced by RCh senktide administration coincided with a dramatic increase in c-Fos expression within arcuate nucleus (ARC) kisspeptin neurones, and was completely blocked by Kp-271 infusion. We substantiate these data with evidence of direct projections of RCh neurones to ARC kisspeptin neurones. Thus, NKB-responsive neurones in the RCh act to stimulate GnRH secretion by inducing kisspeptin release from KNDy neurones.
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Affiliation(s)
- P Grachev
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - K L Porter
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - L M Coolen
- Department of Neurobiology & Anatomical Sciences, The University of Mississippi Medical Center, Jackson, MS, USA
- Department of Physiology & Biophysics, The University of Mississippi Medical Center, Jackson, MS, USA
| | - R B McCosh
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - J M Connors
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - S M Hileman
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - M N Lehman
- Department of Neurobiology & Anatomical Sciences, The University of Mississippi Medical Center, Jackson, MS, USA
| | - R L Goodman
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
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Clarke SA, Dhillo WS. Kisspeptin across the human lifespan:evidence from animal studies and beyond. J Endocrinol 2016; 229:R83-98. [PMID: 27340201 DOI: 10.1530/joe-15-0538] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 03/10/2016] [Indexed: 11/08/2022]
Abstract
Since its first description in 1996, the KISS1 gene and its peptide products, kisspeptins, have increasingly become recognised as key regulators of reproductive health. With kisspeptins acting as ligands for the kisspeptin receptor KISS1R (previously known as GPR54 or KPR54), recent work has consistently shown that administration of kisspeptin across a variety of species stimulates gonadotrophin release through influencing gonadotrophin-releasing hormone secretion. Evidence from both animal and human studies supports the finding that kisspeptins are crucial for ensuring healthy development, with knockout animal models, as well as proband genetic testing in human patients affected by abnormal pubertal development, corroborating the notion that a functional kisspeptin receptor is required for appropriate gonadotrophin secretion. Given the large body of evidence that exists surrounding the influence of kisspeptin in a variety of settings, this review summarises our physiological understanding of the role of these important peptides and their receptors, before proceeding to describe the varying role they play across the reproductive lifespan.
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Affiliation(s)
- Sophie A Clarke
- Department of Investigative MedicineImperial College London, Hammersmith Hospital, London, UK
| | - Waljit S Dhillo
- Department of Investigative MedicineImperial College London, Hammersmith Hospital, London, UK
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Messina A, Langlet F, Chachlaki K, Roa J, Rasika S, Jouy N, Gallet S, Gaytan F, Parkash J, Tena-Sempere M, Giacobini P, Prevot V. A microRNA switch regulates the rise in hypothalamic GnRH production before puberty. Nat Neurosci 2016; 19:835-44. [DOI: 10.1038/nn.4298] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 04/01/2016] [Indexed: 12/12/2022]
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Decourt C, Anger K, Robert V, Lomet D, Bartzen-Sprauer J, Caraty A, Dufourny L, Anderson G, Beltramo M. No Evidence That RFamide-Related Peptide 3 Directly Modulates LH Secretion in the Ewe. Endocrinology 2016; 157:1566-75. [PMID: 26862995 DOI: 10.1210/en.2015-1854] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The neuropeptide RFamide-related peptide 3 (RFRP-3) has been implicated in the control of gonadotropin secretion in both birds and mammals. However, in mammals, depending on species, sex and photoperiod, inhibitory, excitatory, or no effect of RFRP-3 on the plasma concentration of LH has been reported. In the ewe, treatment with RFRP-3 either reduced LH concentration or had no effect, and treatment with an RFRP-3 receptor antagonist (ie, RF9) resulted in increased concentration of plasma LH. To clarify these conflicting results in the present study, a set of experiments was performed in ewes. Multiple iv injections of RFRP-3 (6 × 50 μg) in ovariectomized ewes had no effect on plasma LH pulsatility. In intact ewes a bolus injection (500 μg) or an injection (250, 500, or 1000 μg) followed by a 4-hour perfusion (250, 500, or 1000 μg · h(-1)) of RFRP-3 had no effect on the LH pulse induced by kisspeptin (6.5 μg). In ovariectomized, estrogen-replaced ewes, the LH surge induced by estradiol benzoate was not modified by a 24-hour perfusion of RFRP-3 (500 μg h(-1)). Finally, although treatment with RF9 induced a robust release of LH, treatment with a more selective RFRP-3 receptor antagonist, GJ14, resulted in no evident increase of LH. In contrast to the inhibitory effect previously suggested, our data are more consistent with the concept that RFRP-3 has no direct effect on LH secretion in ewes and that RF9 effect on LH release is likely not RFRP-3 receptor mediated. Hence, RFRP-3 probably has a minor role on the control of LH secretion in the ewe.
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Affiliation(s)
- C Decourt
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - K Anger
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - V Robert
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - D Lomet
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - J Bartzen-Sprauer
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - A Caraty
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - L Dufourny
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - G Anderson
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
| | - M Beltramo
- Unité Mixte de Recherche Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique, Unité Mixte de Recherche 85; Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7247, Université François Rabelais Tours, IFCE) (C.D., K.A., V.R., D.L., J.B.-S., A.C., L.D., M.B.), F-37380 Nouzilly, France; and Centre for Neuroendocrinology and Department of Anatomy (G.A.), University of Otago School of Medical Sciences, Dunedin 9054, New Zealand
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Quillet R, Ayachi S, Bihel F, Elhabazi K, Ilien B, Simonin F. RF-amide neuropeptides and their receptors in Mammals: Pharmacological properties, drug development and main physiological functions. Pharmacol Ther 2016; 160:84-132. [PMID: 26896564 DOI: 10.1016/j.pharmthera.2016.02.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RF-amide neuropeptides, with their typical Arg-Phe-NH2 signature at their carboxyl C-termini, belong to a lineage of peptides that spans almost the entire life tree. Throughout evolution, RF-amide peptides and their receptors preserved fundamental roles in reproduction and feeding, both in Vertebrates and Invertebrates. The scope of this review is to summarize the current knowledge on the RF-amide systems in Mammals from historical aspects to therapeutic opportunities. Taking advantage of the most recent findings in the field, special focus will be given on molecular and pharmacological properties of RF-amide peptides and their receptors as well as on their implication in the control of different physiological functions including feeding, reproduction and pain. Recent progress on the development of drugs that target RF-amide receptors will also be addressed.
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Affiliation(s)
- Raphaëlle Quillet
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Safia Ayachi
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Frédéric Bihel
- Laboratoire Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, Illkirch, France
| | - Khadija Elhabazi
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Brigitte Ilien
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Frédéric Simonin
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France.
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67
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Direct Actions of Kisspeptins on GnRH Neurons Permit Attainment of Fertility but are Insufficient to Fully Preserve Gonadotropic Axis Activity. Sci Rep 2016; 6:19206. [PMID: 26755241 PMCID: PMC4709743 DOI: 10.1038/srep19206] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 12/08/2015] [Indexed: 01/08/2023] Open
Abstract
Kisspeptins, ligands of the receptor, Gpr54, are potent stimulators of puberty and fertility. Yet, whether direct kisspeptin actions on GnRH neurons are sufficient for the whole repertoire of their reproductive effects remains debatable. To dissect out direct vs. indirect effects of kisspeptins on GnRH neurons in vivo, we report herein the detailed reproductive/gonadotropic characterization of a Gpr54 null mouse line with selective re-introduction of Gpr54 expression only in GnRH cells (Gpr54−/−Tg; rescued). Despite preserved fertility, adult rescued mice displayed abnormalities in gonadal microstructure, with signs of precocious ageing in females and elevated LH levels with normal-to-low testosterone secretion in males. Gpr54−/−Tg rescued mice showed also altered gonadotropin responses to negative feedback withdrawal, while luteinizing hormone responses to various gonadotropic regulators were variably affected, with partially blunted relative (but not absolute) responses to kisspeptin-10, NMDA and the agonist of tachykinin receptors, NK2R. Our data confirm that direct effects of kisspeptins on GnRH cells are sufficient to attain fertility. Yet, such direct actions appear to be insufficient to completely preserve proper functionality of gonadotropic axis, suggesting a role of kisspeptin signaling outside GnRH cells.
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68
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Gaytan F, Morales C, Leon S, Garcia-Galiano D, Roa J, Tena-Sempere M. Crowding and Follicular Fate: Spatial Determinants of Follicular Reserve and Activation of Follicular Growth in the Mammalian Ovary. PLoS One 2015; 10:e0144099. [PMID: 26642206 PMCID: PMC4671646 DOI: 10.1371/journal.pone.0144099] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/12/2015] [Indexed: 01/07/2023] Open
Abstract
Initiation of growth of resting ovarian follicles is a key phenomenon for providing an adequate number of mature oocytes in each ovulation, while preventing premature exhaustion of primordial follicle reserve during the reproductive lifespan. Resting follicle dynamics strongly suggest that primordial follicles are under constant inhibitory influences, by mechanisms and factors whose nature remains ill defined. In this work, we aimed to assess the influence of spatial determinants, with special attention to clustering patterns and crowding, on the fate of early follicles in the adult mouse and human ovary. To this end, detailed histological and morphometric analyses, targeting resting and early growing follicles, were conducted in ovaries from mice, either wild type (WT) or genetically modified to lack kisspeptin receptor expression (Kiss1r KO), and healthy adult women. Kiss1r KO mice were studied as model of persistent hypogonadotropism and anovulation. Different qualitative and quantitative indices of the patterns of spatial distribution of resting and early growing follicles in the mouse and human ovary, including the Morisita’s index of clustering, were obtained. Our results show that resting primordial follicles display a clear-cut clustered pattern of spatial distribution in adult mouse and human ovaries, and that resting follicle aggrupation is inversely correlated with the proportion of follicles initiating growth and entering into the growing pool. As a whole, our data suggest that resting follicle crowding, defined by changes in density and clustered pattern of distribution, is a major determinant of follicular activation and the fate of ovarian reserve. Uneven follicle crowding would constitute the structural counterpart of the major humoral regulators of early follicular growth, with potential implications in ovarian ageing and pathophysiology.
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Affiliation(s)
- Francisco Gaytan
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica (IMIBIC)/Hospital Universitario Reina Sofía, 14004, Córdoba, Spain
- * E-mail: (FG); (MT-S)
| | | | - Silvia Leon
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica (IMIBIC)/Hospital Universitario Reina Sofía, 14004, Córdoba, Spain
| | - David Garcia-Galiano
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004, Córdoba, Spain
| | - Juan Roa
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica (IMIBIC)/Hospital Universitario Reina Sofía, 14004, Córdoba, Spain
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica (IMIBIC)/Hospital Universitario Reina Sofía, 14004, Córdoba, Spain
- FiDiPro Program, Department of Physiology, University of Turku, Kiinamyllynkatu 10, FIN-20520, Turku, Finland
- * E-mail: (FG); (MT-S)
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Min L, Leon S, Li H, Pinilla L, Carroll RS, Tena-Sempere M, Kaiser UB. RF9 Acts as a KISS1R Agonist In Vivo and In Vitro. Endocrinology 2015; 156:4639-48. [PMID: 26418326 PMCID: PMC4655216 DOI: 10.1210/en.2015-1635] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
RF9, a reported antagonist of the mammalian gonadotropin-inhibitory hormone receptor, stimulates gonadotropin secretion in mammals. Recent studies have suggested that the stimulatory effect of RF9 on gonadotropin secretion relies on intact kisspeptin receptor (KISS1R) signaling, but the underlying mechanisms remain to be elucidated. Using Chinese Hamster Ovary cells stably transfected with KISS1R, we show that RF9 binds specifically to KISS1R, with a Kd of 1.6 × 10(-5)M, and stimulates an increase in intracellular calcium and inositol phosphate accumulation in a KISS1R-dependent manner, with EC50 values of 3.0 × 10(-6)M and 1.6 × 10(-7)M, respectively. RF9 also stimulated ERK phosphorylation, with a time course similar to that of kisspeptin-10. RFRP-3, the putative endogenous ligand for NPFFR1, did not stimulate inositol phosphate accumulation or pERK, nor did it alter responses to of kisspeptin-10 or RF9. In agreement with these in vitro data, we found that RF9 stimulated a robust LH increase in Npffr1(-/-) mice, similar to that in wild-type littermates, whereas the stimulatory effect of RF9 was markedly reduced in Kiss1r(-/-) and double Kiss1r(-/-)/Npfrr1(-/-) mice. The stimulatory effect of RF9 on LH secretion was restored by the selective rescue of Kiss1r expression in GnRH neurons, in Kiss1r(-/-T) mice. Taken together, our study demonstrates that RF9 acts primarily as a KISS1R agonist, but not as an allosteric modulator, to stimulate LH secretion. Our findings raise questions regarding the utility of RF9 for assessing NPFF1R function and de-emphasize a predominant role of this signaling system in central regulation of reproduction.
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Affiliation(s)
- Le Min
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
| | - Silvia Leon
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
| | - Huan Li
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
| | - Leonor Pinilla
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
| | - Rona S Carroll
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
| | - Manuel Tena-Sempere
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
| | - Ursula B Kaiser
- Division of Endocrinology, Diabetes and Hypertension (L.M., H.L., R.S.C., U.B.K.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Department of Cell Biology, Physiology and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, Córdoba, 14004 Spain; and FiDiPro Program, Department of Physiology (M.T.-S.), University of Turku, FIN-20520 Turku, Finland
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Kim JS, Brownjohn PW, Dyer BS, Beltramo M, Walker CS, Hay DL, Painter GF, Tyndall JDA, Anderson GM. Anxiogenic and Stressor Effects of the Hypothalamic Neuropeptide RFRP-3 Are Overcome by the NPFFR Antagonist GJ14. Endocrinology 2015; 156:4152-62. [PMID: 26259035 DOI: 10.1210/en.2015-1532] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
RFamide-related peptide-3 (RFRP-3) is a recently discovered neuropeptide that has been proposed to play a role in the stress response. We aimed to elucidate the role of RFRP-3 and its receptor, neuropeptide FF (NPFF1R), in modulation of stress and anxiety responses. To achieve this, we characterized a new NPFF1R antagonist because our results showed that the only commercially available putative antagonist, RF9, is in fact an agonist at both NPFF1R and the kisspeptin receptor (KISS1R). We report here the identification and pharmacological characterization of GJ14, a true NPFFR antagonist. In in vivo tests of hypothalamic-pituitary-adrenal (HPA) axis function, GJ14 completely blocked RFRP-3-induced corticosterone release and neuronal activation in CRH neurons. Furthermore, chronic infusion of GJ14 led to anxiolytic-like behavior, whereas RFRP-3 infusion had anxiogenic effects. Mice receiving chronic RFRP-3 infusion also had higher basal circulating corticosterone levels. These results indicate a stimulatory action of RFRP-3 on the HPA axis, consistent with the dense expression of NPFF1R in the vicinity of CRH neurons. Importantly, coinfusion of RFRP-3 and GJ14 completely reversed the anxiogenic and HPA axis-stimulatory effects of RFRP-3. Here we have established the role of RFRP-3 as a regulator of stress and anxiety. We also show that GJ14 can reverse the effects of RFRP-3 both in vitro and in vivo. Infusion of GJ14 causes anxiolysis, revealing a novel potential target for treating anxiety disorders.
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Affiliation(s)
- Joon S Kim
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Phil W Brownjohn
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Blake S Dyer
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Massimiliano Beltramo
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Christopher S Walker
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Debbie L Hay
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Gavin F Painter
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Joel D A Tyndall
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
| | - Greg M Anderson
- Centre for Neuroendocrinology and Department of Anatomy (J.S.K., P.W.B., G.M.A.) and National School of Pharmacy (J.D.A.T.), University of Otago, Dunedin 9054, New Zealand; Glycosyn (B.S.D.), Callaghan Innovation (B.S.D.), and The Ferrier Research Institute (G.F.P.), University of Wellington, Lower Hutt 5010, Victoria, New Zealand; Institut National de la Recherche Agronomique (M.B.), Nouzilly 37380, France; and School of Biological Sciences (C.S.W., D.L.H.), University of Auckland, Auckland 1142, New Zealand
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Selective optogenetic activation of arcuate kisspeptin neurons generates pulsatile luteinizing hormone secretion. Proc Natl Acad Sci U S A 2015; 112:13109-14. [PMID: 26443858 DOI: 10.1073/pnas.1512243112] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Normal reproductive functioning in mammals depends upon gonadotropin-releasing hormone (GnRH) neurons generating a pulsatile pattern of gonadotropin secretion. The neural mechanism underlying the episodic release of GnRH is not known, although recent studies have suggested that the kisspeptin neurons located in the arcuate nucleus (ARN) may be involved. In the present experiments we expressed channelrhodopsin (ChR2) in the ARN kisspeptin population to test directly whether synchronous activation of these neurons would generate pulsatile luteinizing hormone (LH) secretion in vivo. Characterization studies showed that this strategy targeted ChR2 to 70% of all ARN kisspeptin neurons and that, in vitro, these neurons were activated by 473-nm blue light with high fidelity up to 30 Hz. In vivo, the optogenetic activation of ARN kisspeptin neurons at 10 and 20 Hz evoked high amplitude, pulse-like increments in LH secretion in anesthetized male mice. Stimulation at 10 Hz for 2 min was sufficient to generate repetitive LH pulses. In diestrous female mice, only 20-Hz activation generated significant increments in LH secretion. In ovariectomized mice, 5-, 10-, and 20-Hz activation of ARN kisspeptin neurons were all found to evoke LH pulses. Part of the sex difference, but not the gonadal steroid dependence, resulted from differential pituitary sensitivity to GnRH. Experiments in kisspeptin receptor-null mice, showed that kisspeptin was the critical neuropeptide underlying the ability of ARN kisspeptin neurons to generate LH pulses. Together these data demonstrate that synchronized activation of the ARN kisspeptin neuronal population generates pulses of LH.
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72
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Qi X, Zhou W, Li S, Liu Y, Ye G, Liu X, Peng C, Zhang Y, Lin H. Goldfish neurokinin B: Cloning, tissue distribution, and potential role in regulating reproduction. Gen Comp Endocrinol 2015; 221:267-77. [PMID: 25448255 DOI: 10.1016/j.ygcen.2014.10.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 10/16/2014] [Accepted: 10/31/2014] [Indexed: 12/18/2022]
Abstract
Neurokinin B (NKB) is a member of the tackykinin (TAC) family known to play a critical role in the neuroendocrine regulation of reproduction in mammals. However, its biological functions in teleosts are less clear. The aim of this study was to determine the role of NKB in fish reproduction using goldfish as a model. Two transcripts, TAC3a and TAC3b, which encode several NKBs, including NKBa-13, NKBa-10, NKBb-13, and NKBb-11, were cloned. Phylogenetic analysis revealed that NKBa-10 and NKBb-11 are closely related to mammalian NKB, while NKB-13s are more conserved in teleosts. Quantitative real-time PCR analyses in various tissues showed that TAC3a and TAC3b mRNAs were mainly expressed in the brain. In situ hybridization further detected TAC3a and TAC3b mRNAs in several regions of the brain known to be involved in the regulation of reproduction and metabolism, as well as in the neurohypophysis of the pituitary. To investigate the potential role of NKBs in reproduction, goldfish were injected intraperitoneally with synthetic NKBa-13, -10, NKBb-13, or -11 peptides and the mRNA levels of hypothalamic gonadotropin-releasing hormone (GnRH) and pituitary gonadotropin subunits were measured. NKBa-13, -10, or NKBb-13, but not -11, significantly increased hypothalamic salmon GnRH and pituitary FSHβ and LHβ mRNA levels in both female and male goldfish. Finally, ovariectomy increased, while estradiol replacement reduced, TAC3a mRNA levels without affecting TAC3b expression in the hypothalamus. These data suggest that NKBa-13, -10, and NKBb-13 play a role in mediating the estrogen negative feedback regulation of gonadotropins.
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Affiliation(s)
- Xin Qi
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China; Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Wenyi Zhou
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China; Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Shuisheng Li
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yun Liu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China
| | - Gang Ye
- Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Xiaochun Liu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China
| | - Chun Peng
- Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada.
| | - Yong Zhang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China.
| | - Haoran Lin
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, and the Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou 510275, China; College of Ocean, Hainan University, Haikou 570228, China.
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73
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Simavli S, Thompson IR, Maguire CA, Gill JC, Carroll RS, Wolfe A, Kaiser UB, Navarro VM. Substance p regulates puberty onset and fertility in the female mouse. Endocrinology 2015; 156:2313-22. [PMID: 25856429 PMCID: PMC4430622 DOI: 10.1210/en.2014-2012] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Puberty is a tightly regulated process that leads to reproductive capacity. Kiss1 neurons are crucial in this process by stimulating GnRH, yet how Kiss1 neurons are regulated remains unknown. Substance P (SP), an important neuropeptide in pain perception, induces gonadotropin release in adult mice in a kisspeptin-dependent manner. Here, we assessed whether SP, through binding to its receptor NK1R (neurokinin 1 receptor), participates in the timing of puberty onset and fertility in the mouse. We observed that 1) selective NK1R agonists induce gonadotropin release in prepubertal females; 2) the expression of Tac1 (encoding SP) and Tacr1 (NK1R) in the arcuate nucleus is maximal before puberty, suggesting increased SP tone; 3) repeated exposure to NK1R agonists prepubertally advances puberty onset; and 4) female Tac1(-/-) mice display delayed puberty; moreover, 5) SP deficiency leads to subfertility in females, showing fewer corpora lutea and antral follicles and leading to decreased litter size. Thus, our findings support a role for SP in the stimulation of gonadotropins before puberty, acting via Kiss1 neurons to stimulate GnRH release, and its involvement in the attainment of full reproductive capabilities in female mice.
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Affiliation(s)
- Serap Simavli
- Division of Endocrinology, Diabetes and Hypertension (S.S., I.R.T., C.A.M., J.C.G., R.S.C., U.B.K., V.M.N.), Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Department of Pediatrics (A.W.), Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
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Affiliation(s)
- Ashley E Angell
- Neuroscience Graduate Program (A.E.A., R.A.S.) and Departments of Obstetrics and Gynecology (R.A.S.) and Physiology and Biophysics (R.A.S.), University of Washington, Seattle, Washington 98195-7290
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Uenoyama Y, Nakamura S, Hayakawa Y, Ikegami K, Watanabe Y, Deura C, Minabe S, Tomikawa J, Goto T, Ieda N, Inoue N, Sanbo M, Tamura C, Hirabayashi M, Maeda KI, Tsukamura H. Lack of pulse and surge modes and glutamatergic stimulation of luteinising hormone release in Kiss1 knockout rats. J Neuroendocrinol 2015; 27:187-97. [PMID: 25582792 DOI: 10.1111/jne.12257] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 01/05/2015] [Accepted: 01/05/2015] [Indexed: 12/11/2022]
Abstract
Kisspeptin, encoded by the Kiss1 gene, has attracted attention as a key candidate neuropeptide in controlling puberty and reproduction via regulation of gonadotrophin-releasing hormone (GnRH) secretion in mammals. Pioneer studies with Kiss1 or its cognate receptor Gpr54 knockout (KO) mice showed the indispensable role of kisspeptin-GPR54 signalling in the control of animal reproduction, although detailed analyses of gonadotrophin secretion, especially pulsatile and surge-mode of luteinising hormone (LH) secretion, were limited. Thus, in the present study, we have generated Kiss1 KO rats aiming to evaluate a key role of kisspeptin in governing reproduction via pulse and surge modes of GnRH/LH secretion. Kiss1 KO male and female rats showed a complete suppression of pulsatile LH secretion, which is responsible for folliculogenesis and spermatogenesis, and an absence of puberty and atrophic gonads. Kiss1 KO female rats showed no spontaneous LH/follicle-stimulating hormone surge and an oestrogen-induced LH surge, suggesting that the GnRH surge generation system, which is responsible for ovulation, does not function without kisspeptin. Furthermore, challenge of major stimulatory neurotransmitters, such as monosodium glutamate, NMDA and norepinephrine, failed to stimulate LH secretion in Kiss1 KO rats, albeit they stimulated LH release in wild-type controls. Taken together, the results of the present study confirm that kisspeptin plays an indispensable role in generating two modes (pulse and surge) of GnRH/gonadotrophin secretion to regulate puberty onset and normal reproductive performance. In addition, the present study suggests that kisspeptin neurones play a critical role as a hub integrating major stimulatory neural inputs to GnRH neurones, using newly established Kiss1 KO rats, which serve as a useful model for detailed analysis of hormonal profiles.
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Affiliation(s)
- Y Uenoyama
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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Sahin Z, Canpolat S, Ozcan M, Ozgocer T, Kelestimur H. Kisspeptin antagonist prevents RF9-induced reproductive changes in female rats. Reproduction 2015; 149:465-73. [PMID: 25713426 DOI: 10.1530/rep-14-0683] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of this study was to determine the modulatory effects of peptide 234 (p234) (an antagonist of GPR54 receptors) on kisspeptin and RF9 (an RFamide-related peptide antagonist)-induced changes in reproductive functions and energy balance in female rats. Female Sprague-Dawley rats were weaned on postnatal day (pnd) 21. The animals were intracerebroventricularly cannulated under general anesthesia on pnd 23. Groups of female rats were injected with kisspeptin, RF9, p234, kisspeptin plus p234, or RF9 plus p234, daily. The experiments were ended on the day of first diestrus following pnd 60. Kisspeptin or RF9 alone advanced vaginal opening (VO), which was delayed by administration of kisspeptin antagonist alone. In the rats given kisspeptin plus p234 or RF9 plus p234, VO was not different from control rats. Kisspeptin and RF9 elicited significant elevations in circulating LH levels. Coadministrations of kisspeptin or RF9 with p234 decreased LH levels significantly. The use of p234 alone did not cause any significant change in LH secretion. Kisspeptin decreased both food intake and body weight while RF9 decreased only food intake without affecting body weight. The effects of kisspeptin on energy balance were also reversed by central administration of p234. In conclusion, kisspeptin antagonist, p234, modulates the effects of kisspeptin on reproductive functions and energy balance, whereas RF9 seems to exert only its effects on reproductive functions by means of GPR54 signaling in female rats.
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Affiliation(s)
- Zafer Sahin
- Department of PhysiologyFaculty of MedicineDepartment of BiophysicsMedical School, Firat University, Elazig 23119, TurkeyDepartment of PhysiologyMedical School, Inonu University, Malatya, Turkey
| | - Sinan Canpolat
- Department of PhysiologyFaculty of MedicineDepartment of BiophysicsMedical School, Firat University, Elazig 23119, TurkeyDepartment of PhysiologyMedical School, Inonu University, Malatya, Turkey
| | - Mete Ozcan
- Department of PhysiologyFaculty of MedicineDepartment of BiophysicsMedical School, Firat University, Elazig 23119, TurkeyDepartment of PhysiologyMedical School, Inonu University, Malatya, Turkey
| | - Tuba Ozgocer
- Department of PhysiologyFaculty of MedicineDepartment of BiophysicsMedical School, Firat University, Elazig 23119, TurkeyDepartment of PhysiologyMedical School, Inonu University, Malatya, Turkey
| | - Haluk Kelestimur
- Department of PhysiologyFaculty of MedicineDepartment of BiophysicsMedical School, Firat University, Elazig 23119, TurkeyDepartment of PhysiologyMedical School, Inonu University, Malatya, Turkey
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Chakraborty P, Buaas FW, Sharma M, Snyder E, de Rooij DG, Braun RE. LIN28A marks the spermatogonial progenitor population and regulates its cyclic expansion. Stem Cells 2015; 32:860-73. [PMID: 24715688 DOI: 10.1002/stem.1584] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 09/02/2013] [Accepted: 09/05/2013] [Indexed: 12/22/2022]
Abstract
One of the hallmarks of highly proliferative adult tissues is the presence of a stem cell population that produces progenitor cells bound for differentiation. Progenitor cells undergo multiple transit amplifying (TA) divisions before initiating terminal differentiation. In the adult male germline, daughter cells arising from the spermatogonial stem cells undergo multiple rounds of TA divisions to produce undifferentiated clones of interconnected 2, 4, 8, and 16 cells, collectively termed A(undifferentiated) (A(undiff)) spermatogonia, before entering a stereotypic differentiation cascade. Although the number of TA divisions markedly affects the tissue output both at steady state and during regeneration, mechanisms regulating the expansion of the TA cell population are poorly understood in mammals. Here, we show that mice with a conditional deletion of Lin28a in the adult male germline, display impaired clonal expansion of the progenitor TA A(undiff) spermatogonia. The in vivo proliferative activity of Au(ndiff) spermatogonial cells as indicated by BrdU incorporation during S-phase was reduced in the absence of LIN28A. Thus, contrary to the role of LIN28A as a key determinant of cell fate signals in multiple stem cell lineages, in the adult male germline it functions as an intrinsic regulator of proliferation in the population of A(undiff) TA spermatogonia. In addition, neither precocious differentiation nor diminished capacity for self-renewal potential as assessed by transplantation was observed, suggesting that neither LIN28A itself nor the pool of Aal progenitor cells substantially contribute to the functional stem cell compartment.
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78
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Navarro VM, Bosch MA, León S, Simavli S, True C, Pinilla L, Carroll RS, Seminara SB, Tena-Sempere M, Rønnekleiv OK, Kaiser UB. The integrated hypothalamic tachykinin-kisspeptin system as a central coordinator for reproduction. Endocrinology 2015; 156:627-37. [PMID: 25422875 PMCID: PMC4298326 DOI: 10.1210/en.2014-1651] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tachykinins are comprised of the family of related peptides, substance P (SP), neurokinin A (NKA), and neurokinin B (NKB). NKB has emerged as regulator of kisspeptin release in the arcuate nucleus (ARC), whereas the roles of SP and NKA in reproduction remain unknown. This work explores the roles of SP and NKA in the central regulation of GnRH release. First, central infusion of specific agonists for the receptors of SP (neurokinin receptor 1, NK1R), NKA (NK2R) and NKB (NK3R) each induced gonadotropin release in adult male and ovariectomized, estradiol-replaced female mice, which was absent in Kiss1r(-/-) mice, indicating a kisspeptin-dependent action. The NK2R agonist, however, decreased LH release in ovariectomized-sham replaced females, as documented for NK3R agonists but in contrast to the NK1R agonist, which further increased LH release. Second, Tac1 (encoding SP and NKA) expression in the ARC and ventromedial nucleus was inhibited by circulating estradiol but did not colocalize with Kiss1 mRNA. Third, about half of isolated ARC Kiss1 neurons expressed Tacr1 (NK1R) and 100% Tacr3 (NK3R); for anteroventral-periventricular Kiss1 neurons and GnRH neurons, approximately one-fourth expressed Tacr1 and one-tenth Tacr3; Tacr2 (NK2R) expression was absent in all cases. Overall, these results identify a potent regulation of gonadotropin release by the SP/NK1R and NKA/NK2R systems in the presence of kisspeptin-Kiss1r signaling, indicating that they may, along with NKB/NK3R, control GnRH release, at least in part through actions on Kiss1 neurons.
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Affiliation(s)
- Víctor M Navarro
- Division of Endocrinology, Diabetes, and Hypertension (V.M.N., S.S., R.S.C., U.B.K.), Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115; Department of Physiology and Pharmacology (M.A.B., O.K.R.), Oregon Health and Science University, Portland, Oregon 97239; Department of Cell Biology, Physiology, and Immunology (S.L., L.P., M.T.-S.), University of Córdoba; Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición (S.L., L.P., M.T.-S.), Instituto de Salud Carlos III; and Instituto Maimónides de Investigaciones Biomédicas and Hospital Universitario Reina Sofia (S.L., L.P., M.T.-S.), 14004 Córdoba, Spain; Department of Obstetrics and Gynecology (S.S.), Pamukkale University School of Medicine, Denizli, 20020 Turkey; and Massachusetts General Hospital and Harvard Medical School (C.T., S.B.S.), Boston, Massachusetts 02114
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79
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Ahn T, Fergani C, Coolen LM, Padmanabhan V, Lehman MN. Prenatal testosterone excess decreases neurokinin 3 receptor immunoreactivity within the arcuate nucleus KNDy cell population. J Neuroendocrinol 2015; 27:100-10. [PMID: 25496429 PMCID: PMC4412353 DOI: 10.1111/jne.12244] [Citation(s) in RCA: 21] [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: 05/30/2014] [Revised: 11/11/2014] [Accepted: 12/05/2014] [Indexed: 11/29/2022]
Abstract
Prenatal exposure of the female ovine foetus to excess testosterone leads to neuroendocrine disruptions in adulthood, as demonstrated by defects in responsiveness with respect to the ability of gonadal steroids to regulate gonadotrophin-releasing hormone (GnRH) secretion. In the ewe, neurones of the arcuate nucleus (ARC), which co-expresses kisspeptin, neurokinin B (NKB) and dynorphin (termed KNDy cells), play a key role in steroid feedback control of GnRH and show altered peptide expression after prenatal testosterone treatment. KNDy cells also co-localise NKB receptors (NK3R), and it has been proposed that NKB may act as an autoregulatory transmitter in KNDy cells where it participates in the mechanisms underlying steroid negative-feedback. In addition, recent evidence suggests that NKB/NK3R signalling may be involved in the positive-feedback actions of oestradiol leading to the GnRH/luteinising hormone (LH) surge in the ewe. Thus, we hypothesise that decreased expression of NK3R in KNDy cells may be present in the brains of prenatal testosterone-treated animals, potentially contributing to reproductive defects. Using single- and dual-label immunohistochemistry we found NK3R-positive cells in diverse areas of the hypothalamus; however, after prenatal testosterone treatment, decreased numbers of NK3R immunoreactive (-IR) cells were seen only in the ARC. Moreover, dual-label confocal analyses revealed a significant decrease in the percentage of KNDy cells (using kisspeptin as a marker) that co-localised NK3R. To investigate how NKB ultimately affects GnRH secretion in the ewe, we examined GnRH neurones in the preoptic area (POA) and mediobasal hypothalamus (MBH) for the presence of NK3R. Although, consistent with earlier findings, we found no instances of NK3R co-localisation in GnRH neurones in either the POA or MBH; in addition, > 70% GnRH neurones in both areas were contacted by NK3R-IR presynaptic terminals suggesting that, in addition to its role at KNDy cell bodies, NKB may regulate GnRH neurones by presynaptic actions. In summary, the finding of decreased NK3R within KNDy cells in prenatal testosterone-treated sheep complements previous observations of decreased NKB and dynorphin in the same population, and may contribute to deficits in the feedback control of GnRH/LH secretion in this animal model.
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Affiliation(s)
- T Ahn
- Department of Anatomy & Cell Biology, The University of Western Ontario, London, Canada; Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Canada
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80
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Ruiz-Pino F, Garcia-Galiano D, Manfredi-Lozano M, Leon S, Sánchez-Garrido MA, Roa J, Pinilla L, Navarro VM, Tena-Sempere M. Effects and interactions of tachykinins and dynorphin on FSH and LH secretion in developing and adult rats. Endocrinology 2015; 156:576-88. [PMID: 25490143 PMCID: PMC4298329 DOI: 10.1210/en.2014-1026] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Kisspeptin/neurokinin B/dynorphin (KNDy) neurons, which coexpress kisspeptins (Kps), neurokinin B (NKB), and dynorphin (Dyn), regulate gonadotropin secretion. The KNDy model proposes that NKB (a stimulator, through NK3R) and Dyn (an inhibitor, through κ-opioid receptor) shape Kp secretion onto GnRH neurons. However, some aspects of this paradigm remain ill defined. Here we aimed to characterize the following: 1) the effects of NKB signaling on FSH secretion and 2) the role of Dyn in gonadotropin secretion after NK3R activation; 3) additionally, we explored the roles of other tachykinin receptors, NK1R and NK2R, on gonadotropin release. Thus, the effects of the NK3R agonist, senktide, on FSH release were explored across postnatal development in male and female rats; gonadotropin responses to agonists of NK1R substance P and NK2R [neurokinin A (NKA)] were also monitored. Moreover, the effects of senktide on gonadotropin secretion were assessed after antagonizing Dyn actions by nor-binaltorphimine didydrochloride. Before puberty, rats of both sexes showed increased FSH secretion to senktide (and Kp-10). Conversely, adult female rats were irresponsive to senktide in terms of FSH, despite proven LH responses, whereas the adult males did not display FSH or LH responses to senktide, even at high doses. In turn, substance P and NKA stimulated gonadotropin secretion in prepubertal rats, whereas in adults modest gonadotropin responses to NKA were detected. By pretreatment with a Dyn antagonist, adult males became responsive to senktide in terms of LH secretion and displayed elevated basal LH and FSH levels; nor-binaltorphimine didydrochloride treatment uncovered FSH responses to senktide in adult females. Furthermore, the expression of Pdyn and Opkr1 (encoding Dyn and κ-opioid receptor, respectively) in the mediobasal hypothalamus was greater in males than in females at prepubertal ages. Overall, our data contribute to refining our understanding on how the elements of the KNDy node and related factors (ie, other tachykinins) differentially participate in the control of gonadotropins at different stages of rat postnatal maturation.
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Affiliation(s)
- F Ruiz-Pino
- Department of Cell Biology, Physiology, and Immunology (F.R.-P., D.G.-G., M.M.-L., S.L., M.A.S.-G., J.R., L.P., M.T.-S.), University of Córdoba, and Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (F.R.-P., D.G.-G., J.R., L.P., M.T.-S.), and Instituto Maimonides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia (F.R.-P., D.G.-G., J.R., L.P., M.T.-S.), 14004 Córdoba, Spain; and Division of Endocrinology, Diabetes, and Hypertension (V.M.N.), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
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81
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Leon S, Tena-Sempere M. Dissecting the Roles of Gonadotropin-Inhibitory Hormone in Mammals: Studies Using Pharmacological Tools and Genetically Modified Mouse Models. Front Endocrinol (Lausanne) 2015; 6:189. [PMID: 26779117 PMCID: PMC4700143 DOI: 10.3389/fendo.2015.00189] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/10/2015] [Indexed: 12/24/2022] Open
Abstract
Reproduction is essential for perpetuation of the species and, hence, is controlled by a sophisticated network of regulatory factors of central and peripheral origin that integrate at the hypothalamic-pituitary-gonadal (HPG) axis. Among the central regulators of reproduction, kisspeptins, as major stimulatory drivers of gonadotropin-releasing hormone (GnRH) neurosecretion, have drawn considerable interest in the last decade. However, the dynamic, if not cyclic (in the female), nature of reproductive function and the potency of kisspeptins and other stimulatory signals of the HPG axis make tenable the existence of counterbalance inhibitory mechanisms, which may keep stimulation at check and would allow adaptation of reproductive maturation and function to different endogenous and environmental conditions. In this context, discovery of the gonadotropin-inhibitory hormone (GnIH) in birds, and its mammalian homolog, RFRP, opened up the exciting possibility that this inhibitory signal might operate centrally to suppress, directly or indirectly, GnRH/gonadotropin secretion, thus reciprocally cooperating with other stimulatory inputs in the dynamic regulation of the reproductive hypothalamic-pituitary unit. After more than 15 years of active research, the role of GnIH/RFRP in the control of the HPG axis has been documented in different species. Yet, important aspects of the physiology of this system, especially regarding its relative importance and actual roles in the control of key facets of reproductive function, remain controversial. In the present work, we aim to provide a critical review of recent developments in this area, with special attention to studies in rodent models, using pharmacological tools and functional genomics. In doing so, we intend to endow the reader with an updated view of what is known (and what is not known) about the physiological role of GnIH/RFRP signaling in the control of mammalian reproduction.
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Affiliation(s)
- Silvia Leon
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
- Instituto de Salud Carlos III, CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia (IMIBIC/HURS), Córdoba, Spain
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
- Instituto de Salud Carlos III, CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia (IMIBIC/HURS), Córdoba, Spain
- FiDiPro Program, Department of Physiology, University of Turku, Turku, Finland
- *Correspondence: Manuel Tena-Sempere,
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82
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Piet R, de Croft S, Liu X, Herbison AE. Electrical properties of kisspeptin neurons and their regulation of GnRH neurons. Front Neuroendocrinol 2015; 36:15-27. [PMID: 24907402 DOI: 10.1016/j.yfrne.2014.05.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 04/01/2014] [Accepted: 05/27/2014] [Indexed: 01/19/2023]
Abstract
Kisspeptin neurons are critical components of the neuronal network controlling the activity of the gonadotropin-releasing hormone (GnRH) neurons. A variety of genetically-manipulated mouse models have recently facilitated the study of the electrical activity of the two principal kisspeptin neuron populations located in the rostral periventricular area of the third ventricle (RP3V) and arcuate nucleus (ARN) in acute brain slices. We discuss here the mechanisms and pathways through which kisspeptin neurons regulate GnRH neuron activity. We then examine the different kisspeptin-green fluorescent protein mouse models being used for kisspeptin electrophysiology and the data obtained to date for RP3V and ARN kisspeptin neurons. In light of these new observations on the spontaneous firing rates, intrinsic membrane properties, and neurotransmitter regulation of kisspeptin neurons, we speculate on the physiological roles of the different kisspeptin populations.
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Affiliation(s)
- Richard Piet
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Simon de Croft
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Xinhuai Liu
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Allan E Herbison
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
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83
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Li Q, Millar RP, Clarke IJ, Smith JT. Evidence that Neurokinin B Controls Basal Gonadotropin-Releasing Hormone Secretion but Is Not Critical for Estrogen-Positive Feedback in Sheep. Neuroendocrinology 2015; 101:161-74. [PMID: 25677216 DOI: 10.1159/000377702] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 02/04/2015] [Indexed: 11/19/2022]
Abstract
BACKGROUND Loss-of-function mutations in genes encoding kisspeptin or neurokinin B (NKB) or their receptors cause infertility. NKB is coproduced in kisspeptin neurons in the arcuate nucleus (ARC), and these neurons also produce the NKB receptor (NK3R), allowing autosynaptic function. We tested the hypothesis that NKB action in ARC kisspeptin neurons is aligned with increased pulsatile secretion of luteinizing hormone (LH) and/or activation of the estrogen-induced LH surge in ewes. METHODS Using in situ hybridization and immunohistochemistry, we examined NKB expression in kisspeptin neurons during the ovine estrous cycle. We infused kisspeptin, senktide (an NK3R agonist), or dynorphin into the lateral ventricle during the luteal phase of the estrous cycle to determine effects on pulsatile LH secretion. Finally, we examined the effect of an NK3R antagonist (MRK-08) in ovariectomized ewes. RESULTS NKB (Tac3) mRNA expression in mid-ARC kisspeptin neurons was elevated during the mid-to-late follicular phase of the estrous cycle. The number of NKB-immunoreactive cells and NKB/kisspeptin terminals in the median eminence was similar during the estrous cycle. Kisspeptin and senktide increased LH pulse frequency and mean LH levels. Central MRK-08 infusion eliminated the LH pulses but did not prevent an estrogen-positive feedback on LH secretion. CONCLUSIONS NKB expression in ARC kisspeptin neurons is upregulated during the late follicular phase of the estrous cycle, when the pulsatile secretion of gonadotropin-releasing hormone (GnRH)/LH is maximal. When GnRH/LH secretion is minimal, central senktide infusion induces LH secretion, similar to the response to kisspeptin. Although the increase in LH in response to senktide appeared surge-like, we did not observe any change in the surge following NK3R antagonist treatment. We conclude that NKB plays a role in increasing basal GnRH/LH pulsatility in the follicular phase of the cycle but is not essential for estrogen-induced positive feedback.
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Affiliation(s)
- Qun Li
- Department of Physiology, Monash University, Clayton, Vic., Australia
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84
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Liu X, Herbison AE. RF9 excitation of GnRH neurons is dependent upon Kiss1r in the adult male and female mouse. Endocrinology 2014; 155:4915-24. [PMID: 25322463 DOI: 10.1210/en.2014-1517] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The neuropeptide FF receptor antagonist 1-adamantanecarbonyl-Arg-Phe-NH2 trifluoroacetate salt (RF9) has been found to be a remarkably potent activator of gonadotropin secretion in mammals. However, the mechanism of RF9 action on the reproductive axis is unknown. Using acute brain slice electrophysiology in genetically modified mouse models, we have investigated the possibility that RF9 may activate GnRH neurons. In transgenic GnRH-GFP male and female mice, RF9 was found to exert potent, dose-dependent, stimulatory effects on the firing rate of approximately 70% of GnRH neurons. These effects occurred directly on GnRH neurons and were independent of fast amino acid transmission. To assess RF9's action as an neuropeptide FF receptor antagonist at the GnRH neuron, its ability to antagonize the inhibitory effects of RFamide-related peptide-3 on GnRH neuron firing was examined. RF9 exhibited variable ability to prevent the inhibitory effects of RFamide-related peptide-3 on GnRH neurons. Whole-cell recordings from GnRH neurons showed that RF9 generated an inward current in GnRH neurons reminiscent of that evoked by kisspeptin. We therefore examined RF9 actions in kisspeptin receptor knockout mice. RF9 was found to have no effects at all on GnRH neurons in GnRH-GFP;Kiss1r-null mice, although these cells exhibited normal intrinsic electrical properties and remained responsive to GABA and glutamate. This study reveals that RF9 directly activates GnRH neurons in the mouse and that this is dependent upon Kiss1r expression.
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Affiliation(s)
- Xinhuai Liu
- Centre for Neuroendocrinology and Department of Physiology, University of Otago, School of Medical Sciences, Dunedin 9054, New Zealand
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85
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Porter KL, Hileman SM, Hardy SL, Nestor CC, Lehman MN, Goodman RL. Neurokinin-3 receptor activation in the retrochiasmatic area is essential for the full pre-ovulatory luteinising hormone surge in ewes. J Neuroendocrinol 2014; 26:776-84. [PMID: 25040132 PMCID: PMC4201879 DOI: 10.1111/jne.12180] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/18/2014] [Accepted: 07/14/2014] [Indexed: 11/30/2022]
Abstract
Neurokinin B (NKB) is essential for human reproduction and has been shown to stimulate luteinising hormone (LH) secretion in several species, including sheep. Ewes express the neurokinin-3 receptor (NK3R) in the retrochiasmatic area (RCh) and there is one report that placement of senktide, an NK3R agonist, therein stimulates LH secretion that resembles an LH surge in ewes. In the present study, we first confirmed that local administration of senktide to the RCh produced a surge-like increase in LH secretion, and then tested the effects of this agonist in two other areas implicated in the control of LH secretion and where NK3R is found in high abundance: the preoptic area (POA) and arcuate nucleus (ARC). Bilateral microimplants containing senktide induced a dramatic surge-like increase in LH when given in the POA similar to that seen with RCh treatment. By contrast, senktide treatment in the ARC resulted in a much smaller but significant increase in LH concentrations suggestive of an effect on tonic secretion. The possible role of POA and RCh NK3R activation in the LH surge was next tested by treating ewes with SB222200, an NK3R antagonist, in each area during an oestradiol-induced LH surge. SB222200 in the RCh, but not in the POA, reduced the LH surge amplitude by approximately 40% compared to controls, indicating that NK3R activation in the former region is essential for full expression of the pre-ovulatory LH surge. Based on these data, we propose that the actions of NKB in the RCh are an important component of the pre-ovulatory LH surge in ewes.
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Affiliation(s)
- K L Porter
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
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86
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Hu G, Lin C, He M, Wong AOL. Neurokinin B and reproductive functions: "KNDy neuron" model in mammals and the emerging story in fish. Gen Comp Endocrinol 2014; 208:94-108. [PMID: 25172151 DOI: 10.1016/j.ygcen.2014.08.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 08/12/2014] [Accepted: 08/14/2014] [Indexed: 12/13/2022]
Abstract
In mammals, neurokinin B (NKB), the gene product of the tachykinin family member TAC3, is known to be a key regulator for episodic release of luteinizing hormone (LH). Its regulatory actions are mediated by a subpopulation of kisspeptin neurons within the arcuate nucleus with co-expression of NKB and dynorphin A (commonly called the "KNDy neurons"). By forming an "autosynaptic feedback loop" within the hypothalamus, the KNDy neurons can modulate gonadotropin-releasing hormone (GnRH) pulsatility and subsequent LH release in the pituitary. NKB regulation of LH secretion has been recently demonstrated in zebrafish, suggesting that the reproductive functions of NKB may be conserved from fish to mammals. Interestingly, the TAC3 genes in fish not only encode the mature peptide of NKB but also a novel tachykinin-like peptide, namely NKB-related peptide (or neurokinin F). Recent studies in zebrafish also reveal that the neuroanatomy of TAC3/kisspeptin system within the fish brain is quite different from that of mammals. In this article, the current ideas of "KNDy neuron" model for GnRH regulation and steroid feedback, other reproductive functions of NKB including its local actions in the gonad and placenta, the revised model of tachykinin evolution from invertebrates to vertebrates, as well as the emerging story of the two TAC3 gene products in fish, NKB and NKB-related peptide, will be reviewed with stress on the areas with interesting questions for future investigations.
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Affiliation(s)
- Guangfu Hu
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Chengyuan Lin
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Mulan He
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Anderson O L Wong
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China.
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87
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Li SY, Li XF, Hu MH, Shao B, Poston L, Lightman SL, O'Byrne KT. Neurokinin B receptor antagonism decreases luteinising hormone pulse frequency and amplitude and delays puberty onset in the female rat. J Neuroendocrinol 2014; 26:521-7. [PMID: 24863620 DOI: 10.1111/jne.12167] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 04/17/2014] [Accepted: 05/17/2014] [Indexed: 01/28/2023]
Abstract
The neural mechanisms controlling puberty onset remain enigmatic. Humans with loss of function mutations in TAC3 or TACR3, the genes encoding neurokinin B (NKB) or its receptor, neurokinin-3 receptor (NK3R), respectively, present with severe congenital gonadotrophin deficiency and pubertal failure. Animal studies have shown ambiguous actions of NKB-NK3R signalling with respect to controlling puberty onset. The present study aimed to determine the role of endogenous NKB-NK3R signalling in the control of pulsatile luteinising hormone (LH) secretion and the timing of puberty onset, and also whether precocious pubertal onset as a result of an obesogenic diet is similarly regulated by this neuropeptide system. Prepubertal female rats, chronically implanted with i.c.v. cannulae, were administered SB222200, a NK3R antagonist, or artificial cerebrospinal fluid via an osmotic mini-pump for 14 days. SB222200 significantly delayed the onset of vaginal opening and first oestrus (as markers of puberty) compared to controls in both normal and high-fat diet fed animals. Additionally, serial blood sampling, via chronic indwelling cardiac catheters, revealed that the increase in LH pulse frequency was delayed and that the LH pulse amplitude was reduced in response to NK3R antagonism, regardless of dietary status. These data suggest that endogenous NKB-NK3R signalling plays a role in controlling the timing of puberty and the associated acceleration of gonadotrophin-releasing hormone pulse generator frequency in the female rat.
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Affiliation(s)
- S Y Li
- Division of Women's Health, Women's Health Academic Centre, School of Medicine, King's College London, Guy's Campus, London, UK; Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
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88
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León S, García-Galiano D, Ruiz-Pino F, Barroso A, Manfredi-Lozano M, Romero-Ruiz A, Roa J, Vázquez MJ, Gaytan F, Blomenrohr M, van Duin M, Pinilla L, Tena-Sempere M. Physiological roles of gonadotropin-inhibitory hormone signaling in the control of mammalian reproductive axis: studies in the NPFF1 receptor null mouse. Endocrinology 2014; 155:2953-65. [PMID: 24823392 DOI: 10.1210/en.2014-1030] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
RF-amide-related peptide-3 (RFRP-3), the mammalian ortholog of the avian gonadotropin-inhibiting hormone (GnIH), operates via the NPFF1 receptor (NPFF1R) to repress the reproductive axis, therefore acting as counterpart of the excitatory RF-amide peptide, kisspeptin (ligand of Gpr54). In addition, RFRP-3 modulates feeding and might contribute to the integrative control of energy homeostasis and reproduction. Yet, the experimental evidence supporting these putative functions is mostly indirect, and the physiological roles of RFRP-3 remain debatable and obscured by the lack of proper analytical tools and models. To circumvent these limitations, we characterize herein the first mouse line with constitutive inactivation of NPFF1R. Ablation of NPFF1R did not compromise fertility; rather, litters from NPFF1R null mice were larger than those from wild-type animals. Pubertal timing was not altered in NPFF1R deficient mice; yet, pre-pubertal knockout (KO) males displayed elevated LH levels, which normalized after puberty. Adult NPFF1R null male mice showed increased Kiss1 expression in the hypothalamic arcuate nucleus, higher serum FSH levels, and enhanced LH responses to GnRH. However, genetic elimination of NPFF1R was unable to reverse the state of hypogonadism caused by the lack of kisspeptin signaling, as revealed by double NPFF1R/Gpr54 KO mice. NPFF1R null mice displayed altered feedback responses to gonadal hormone withdrawal. In addition, metabolic challenges causing gonadotropin suppression, such as short-term fasting and high-fat diet, were less effective in dampening LH secretion in NPFF1R-deficient male mice, suggesting that absence of this inhibitory pathway partially prevented gonadotropin suppression by metabolic stress. Our data are the first to document the impact of elimination of GnIH signaling on reproductive parameters and their modulation by metabolic challenges. Whereas, in keeping with its inhibitory role, the NPFF1R pathway seems dispensable for preserved puberty and fertility, our results surface different alterations due to the lack of GnIH signaling that prominently include changes in the sensitivity to fasting- and obesity-associated hypogonadotropism.
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Affiliation(s)
- Silvia León
- Department of Cell Biology, Physiology and Immunology, University of Córdoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III; and Instituto Maimónides de Investigación Biomédica de Córdoba/Hospital Universitario Reina Sofia, 14004 Córdoba, Spain
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89
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Dorfman MD, Garcia-Rudaz C, Alderman Z, Kerr B, Lomniczi A, Dissen GA, Castellano JM, Garcia-Galiano D, Gaytan F, Xu B, Tena-Sempere M, Ojeda SR. Loss of Ntrk2/Kiss1r signaling in oocytes causes premature ovarian failure. Endocrinology 2014; 155:3098-111. [PMID: 24877631 PMCID: PMC4097998 DOI: 10.1210/en.2014-1111] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Neurotrophins (NTs), once believed to be neural-specific trophic factors, are now known to also provide developmental cues to non-neural cells. In the ovary, NTs contribute to both the formation and development of follicles. Here we show that oocyte-specific deletion of the Ntrk2 gene that encodes the NTRK2 receptor (NTRK2) for neurotrophin-4/5 and brain-derived neurotrophic factor (BDNF) results in post-pubertal oocyte death, loss of follicular organization, and early adulthood infertility. Oocytes lacking NTRK2 do not respond to gonadotropins with activation of phosphatidylinositol 3-kinase (PI3K)-AKT-mediated signaling. Before puberty, oocytes only express a truncated NTRK2 form (NTRK2.T1), but at puberty full-length (NTRK2.FL) receptors are rapidly induced by the preovulatory gonadotropin surge. A cell line expressing both NTRK2.T1 and the kisspeptin receptor (KISS1R) responds to BDNF stimulation with activation of Ntrk2 expression only if kisspeptin is present. This suggests that BDNF and kisspeptin that are produced by granulosa cells (GCs) of periovulatory follicles act in concert to mediate the effect of gonadotropins on Ntrk2 expression in oocytes. In keeping with this finding, the oocytes of NTRK2-intact mice fail to respond to gonadotropins with increased Ntrk2 expression in the absence of KISS1R. Our results demonstrate that the preovulatory gonadotropin surge promotes oocyte survival at the onset of reproductive cyclicity by inducing oocyte expression of NTRK2.FL receptors that set in motion an AKT-mediated survival pathway. They also suggest that gonadotropins activate NTRK2.FL expression via a dual communication pathway involving BDNF and kisspeptin produced in GCs and their respective receptors NTRK2.T1 and KISS1R expressed in oocytes.
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Affiliation(s)
- Mauricio D Dorfman
- Division of Neuroscience (M.D.D., C.G.-R., Z.A., B.K., A.L., G.A.D., J.M.C., S.R.O.), Oregon National Primate Research Center/Oregon Health and Science University, Beaverton, Oregon 97006; Department of Cell Biology, Physiology and Immunology (D.G.-G., F.G., M.T.-S.), University of Córdoba; Centro de Investigacion Biomedica en Red (CIBER) Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III; and Instituto Maimónides de Investigaciones Biomédicas/Hospital Universitario Reina Sofia, Cordoba, Spain 14004; and Department of Pharmacology and Physiology (B.X.), Georgetown University Medical Center, Washington DC 20057
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90
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Gaytan F, Garcia-Galiano D, Dorfman MD, Manfredi-Lozano M, Castellano JM, Dissen GA, Ojeda SR, Tena-Sempere M. Kisspeptin receptor haplo-insufficiency causes premature ovarian failure despite preserved gonadotropin secretion. Endocrinology 2014; 155:3088-97. [PMID: 24885574 PMCID: PMC4611053 DOI: 10.1210/en.2014-1110] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Premature ovarian failure (POF) affects 1% of women in reproductive age, but its etiology remains uncertain. Whereas kisspeptins, the products of Kiss1 that act via Kiss1r (aka, Gpr54), are known to operate at the hypothalamus to control GnRH/gonadotropin secretion, additional actions at other reproductive organs, including the ovary, have been proposed. Yet, their physiological relevance is still unclear. We present here a series of studies in Kiss1r haplo-insufficient and null mice suggesting a direct role of kisspeptin signaling in the ovary, the defect of which precipitates a state of primary POF. Kiss1r hypomorph mice displayed a premature decline in ovulatory rate, followed by progressive loss of antral follicles, oocyte loss, and a reduction in all categories of preantral follicles. These alterations were accompanied by reduced fertility. Because of this precocious ovarian ageing, mice more than 48 weeks of age showed atrophic ovaries, lacking growing follicles and corpora lutea. This phenomenon was associated with a drop in ovarian Kiss1r mRNA expression, but took place in the absence of a decrease in circulating gonadotropins. In fact, FSH levels increased in aged hypomorph animals, reflecting loss of follicular function. In turn, Kiss1r-null mice, which do not spontaneously ovulate and have arrested follicular development, failed to show normal ovulatory responses to standard gonadotropin priming and required GnRH prestimulation during 1 week in order to display gonadotropin-induced ovulation. Yet, the magnitude of such ovulatory responses was approximately half of that seen in control immature wild-type animals. Altogether, our data are the first to demonstrate that Kiss1r haplo-insufficiency induces a state of POF, which is not attributable to defective gonadotropin secretion. We also show that the failure of follicular development and ovulation linked to the absence of Kiss1r cannot be fully rescued by (even extended) gonadotropin replacement. These findings suggest a direct ovarian role of kisspeptin signaling, the perturbation of which may contribute to the pathogenesis of POF.
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Affiliation(s)
- Francisco Gaytan
- Department of Cell Biology, Physiology and Immunology (F.G., D.G-G., M.M-L., M.T-S.), University of Cordoba; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III; and Instituto Maimónides de Investigación Biomédica (IMIBIC)/Hospital Universitario Reina Sofia (HURS), 14004 Cordoba, Spain; and Division of Neuroscience (M.D.D., J.M.C., G.A.D., S.R.O.) Oregon National Primate Research Center/Oregon Health and Science University, Beaverton, Oregon 97006
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91
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Grachev P, Li XF, Hu MH, Li SY, Millar RP, Lightman SL, O'Byrne KT. Neurokinin B signaling in the female rat: a novel link between stress and reproduction. Endocrinology 2014; 155:2589-601. [PMID: 24708241 DOI: 10.1210/en.2013-2038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Acute systemic stress disrupts reproductive function by inhibiting pulsatile gonadotropin secretion. The underlying mechanism involves stress-induced suppression of the GnRH pulse generator, the functional unit of which is considered to be the hypothalamic arcuate nucleus kisspeptin/neurokinin B/dynorphin A neurons. Agonists of the neurokinin B (NKB) receptor (NK3R) have been shown to suppress the GnRH pulse generator, in a dynorphin A (Dyn)-dependent fashion, under hypoestrogenic conditions, and Dyn has been well documented to mediate several stress-related central regulatory functions. We hypothesized that the NKB/Dyn signaling cascade is required for stress-induced suppression of the GnRH pulse generator. To investigate this ovariectomized rats, iv administered with Escherichia coli lipopolysaccharide (LPS) following intracerebroventricular pretreatment with NK3R or κ-opioid receptor (Dyn receptor) antagonists, were subjected to frequent blood sampling for hormone analysis. Antagonism of NK3R, but not κ-opioid receptor, blocked the suppressive effect of LPS challenge on LH pulse frequency. Neither antagonist affected LPS-induced corticosterone secretion. Hypothalamic arcuate nucleus NKB neurons project to the paraventricular nucleus, the major hypothalamic source of the stress-related neuropeptides CRH and arginine vasopressin (AVP), which have been implicated in the stress-induced suppression of the hypothalamic-pituitary-gonadal axis. A separate group of ovariectomized rats was, therefore, used to address the potential involvement of central CRH and/or AVP signaling in the suppression of LH pulsatility induced by intracerebroventricular administration of a selective NK3R agonist, senktide. Neither AVP nor CRH receptor antagonists affected the senktide-induced suppression of the LH pulse; however, antagonism of type 2 CRH receptors attenuated the accompanying elevation of corticosterone levels. These data indicate that the suppression of the GnRH pulse generator by acute systemic stress requires hypothalamic NKB/NK3R signaling and that any involvement of CRH therewith is functionally upstream of NKB.
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Affiliation(s)
- P Grachev
- Division of Women's Health (P.G., X.F.L., M.H.H., S.Y.L., K.T.O.), School of Medicine, King's College London, United Kingdom; Mammal Research Institute (R.P.M.), University of Pretoria, Pretoria, South Africa; Medical Research Council Receptor Biology Unit, University of Cape Town, Cape Town, South Africa; Centre for Integrative Physiology, University of Edinburgh, Scotland; and Henry Wellcome Laboratory for Integrative Neuroscience & Endocrinology (S.L.L.), University of Bristol, Bristol, United Kingdom
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92
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Abstract
Metabolic status has long been thought to determine reproductive status, with abnormal metabolic phenotypes altering reproductive cascades, such as the onset of puberty. In this issue of the JCI, Tolson and colleagues provide evidence that kisspeptin, a hormone that promotes sexual maturation, regulates metabolism. Female mice lacking the kisspeptin receptor (KISS1R) gained more weight than control animals, and this weight gain was caused not by increased food consumption, but by an overall decrease in energy and metabolism. While this study provides a direct link between the kisspeptin pathway and metabolic output, more work will need to be done to determine whether alterations in this pathway contribute to human obesity.
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93
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Abstract
Sexual maturation and somatic growth cessation are associated with adolescent development, which is precisely controlled by interconnected neuroendocrine regulatory pathways in the endogenous endocrine system. The pituitary gland is one of the key regulators of the endocrine system. By analyzing the RNA sequencing (RNA-seq) transcriptome before and after sexual maturation, in this study, we characterized the global gene expression patterns in zebrafish pituitaries at 45 and 90 days post-fertilization (dpf). A total of 15 043 annotated genes were expressed in the pituitary tissue, 3072 of which were differentially expressed with a greater than or equal to twofold change between pituitaries at 45 and 90 dpf. In the pituitary transcriptome, the most abundant transcript was gh. The expression levels of gh remained high even after sexual maturation at 90 dpf. Among the eight major pituitary hormone genes, lhb was the only gene that exhibited a significant change in its expression levels between 45 and 90 dpf. Significant changes in the pituitary transcripts included genes involved in the regulation of immune responses, bone metabolism, and hormone secretion processes during the juvenile-sexual maturity transition. Real-time quantitative PCR analysis was carried out to verify the RNA-seq transcriptome results and demonstrated that the expression patterns of the eight major pituitary hormone genes did not exhibit a significant gender difference at 90 dpf. For the first time, we report the quantitative global gene expression patterns at the juvenile and sexual maturity stages. These expression patterns may account for the dynamic neuroendocrine regulation observed in body metabolism.
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Affiliation(s)
- Wenxia He
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of ChinaKey Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of China
| | - Xiangyan Dai
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of ChinaKey Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of China
| | - Xiaowen Chen
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of ChinaKey Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of China
| | - Jiangyan He
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of China
| | - Zhan Yin
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of Hydrobiology, Chinese Academy of Sciences, 7 Donghu South Road, Wuhan, Hubei 430072, People's Republic of ChinaUniversity of Chinese Academy of SciencesBeijing, People's Republic of China
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94
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Neal-Perry G, Yao D, Shu J, Sun Y, Etgen AM. Insulin-like growth factor-I regulates LH release by modulation of kisspeptin and NMDA-mediated neurotransmission in young and middle-aged female rats. Endocrinology 2014; 155:1827-37. [PMID: 24617524 PMCID: PMC3990844 DOI: 10.1210/en.2013-1682] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This study investigated potential mechanisms by which age and IGF-I receptor (IGF-Ir) signaling in the neuroendocrine hypothalamus affect estradiol-positive feedback effects on GnRH neuronal activation and on kisspeptin and N-methyl-D-aspartate (NMDA)-induced LH release and on the abundance of NMDA receptor subunits Nr1 and Nr2b and Kiss1r transcript and protein in the hypothalamus of young and middle-aged female rats. We infused vehicle, IGF-I, or JB-1, a selective antagonist of IGF-Ir, into the third ventricle of ovariectomized female rats primed with estradiol or vehicle and injected with vehicle, kisspeptin (3 or 30 nmol/kg), or NMDA (15 or 30 mg/kg). Regardless of dose, NMDA and kisspeptin resulted in significantly more LH release, GnRH/c-Fos colabeling, and c-Fos immunoreative cells in young than in middle-aged females. Estradiol priming significantly increased Kiss1r, Nr1, and Nr2b receptor transcript and protein abundance in young but not middle-aged female hypothalamus. JB-1 attenuated kisspeptin and NMDA-induced LH release, numbers of GnRH/c-Fos and c-Fos cells, and Kiss1r, Nr1, and Nr2b transcript and protein abundance in young females to levels observed in middle-aged females. IGF-I significantly enhanced NMDA and kisspeptin-induced LH release in middle-aged females without increasing numbers of GnRH/c-Fos or c-Fos immunoreactive cells. IGF-I infusion in middle-aged females also increased Kiss1r, Nr1, and Nr2b protein and transcript to levels that were equivalent to young estradiol-primed females. These findings indicate that age-related changes in estradiol-regulated responsiveness to excitatory input from glutamate and kisspeptin reflect reduced IGF-Ir signaling.
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MESH Headings
- Aging
- Animals
- Female
- Gene Expression Regulation, Developmental/drug effects
- Hypothalamo-Hypophyseal System/growth & development
- Hypothalamo-Hypophyseal System/metabolism
- Hypothalamus/cytology
- Hypothalamus/drug effects
- Hypothalamus/growth & development
- Hypothalamus/metabolism
- Infusions, Intraventricular
- Insulin-Like Growth Factor I/administration & dosage
- Insulin-Like Growth Factor I/analogs & derivatives
- Insulin-Like Growth Factor I/antagonists & inhibitors
- Insulin-Like Growth Factor I/metabolism
- Kisspeptins/metabolism
- Luteinizing Hormone/metabolism
- N-Methylaspartate/metabolism
- Nerve Tissue Proteins/agonists
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neuroendocrine Cells/cytology
- Neuroendocrine Cells/drug effects
- Neuroendocrine Cells/metabolism
- Oligopeptides/administration & dosage
- Oligopeptides/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptor, IGF Type 1/agonists
- Receptor, IGF Type 1/antagonists & inhibitors
- Receptor, IGF Type 1/metabolism
- Receptors, G-Protein-Coupled/biosynthesis
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Kisspeptin-1
- Receptors, N-Methyl-D-Aspartate/agonists
- Receptors, N-Methyl-D-Aspartate/genetics
- Receptors, N-Methyl-D-Aspartate/metabolism
- Signal Transduction/drug effects
- Synaptic Transmission/drug effects
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Affiliation(s)
- Genevieve Neal-Perry
- Department of Obstetrics and Gynecology (G.N.-P., J.S., Y.S., A.M.E.) and the Dominick P. Purpura Department of Neuroscience (G.N.-P., A.M.E.), Albert Einstein College of Medicine, Bronx, New York 10461; and Internal Medicine of Tongji Hospital (D.Y.), Huazhong University of Science and Technology, Wuhan 430030, R.P. China
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95
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Thorson JF, Prezotto LD, Cardoso RC, Sharpton SM, Edwards JF, Welsh TH, Riggs PK, Caraty A, Amstalden M, Williams GL. Hypothalamic Distribution, Adenohypophyseal Receptor Expression, and Ligand Functionality of RFamide-Related Peptide 3 in the Mare During the Breeding and Nonbreeding Seasons1. Biol Reprod 2014; 90:28. [DOI: 10.1095/biolreprod.113.112185] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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96
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Goodman RL, Coolen LM, Lehman MN. A role for neurokinin B in pulsatile GnRH secretion in the ewe. Neuroendocrinology 2014; 99:18-32. [PMID: 24008670 PMCID: PMC3976461 DOI: 10.1159/000355285] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 08/24/2013] [Indexed: 01/15/2023]
Abstract
The recent description of infertility in humans with loss-of-function mutations in genes for neurokinin B (NKB) or its receptor (NK3R) has focused attention on the importance of this tachykinin in the control of GnRH secretion. In a number of species, NKB neurons in the arcuate nucleus also produce two other neuropeptides implicated in the control of GnRH secretion: (1) kisspeptin, which is also essential for fertility in humans, and (2) dynorphin, an inhibitory endogenous opioid peptide. A number of characteristics of this neuronal population led to the hypothesis that they may be responsible for driving synchronous release of GnRH during episodic secretion of this hormone, and there is now considerable evidence to support this hypothesis in sheep and goats. In this article, we briefly review the history of work on the NKB system in sheep and then review the anatomy of NKB signaling in the ewe. We next describe evidence from a number of species that led to development of a model for the role of these neurons in episodic GnRH secretion. Finally, we discuss recent experiments in sheep and goats that tested this hypothesis and led to a modified version of the model, and then broaden our focus to briefly consider the possible roles of NKB in other species and systems.
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Affiliation(s)
- Robert L Goodman
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, W.Va., USA
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97
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Yeo SH, Clarkson J, Herbison AE. Kisspeptin-gpr54 signaling at the GnRH neuron is necessary for negative feedback regulation of luteinizing hormone secretion in female mice. Neuroendocrinology 2014; 100:191-7. [PMID: 25301053 DOI: 10.1159/000368608] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 09/10/2014] [Indexed: 11/19/2022]
Abstract
Kisspeptin-Gpr54 signaling is critical for regulating the activity of gonadotropin-releasing hormone (GnRH) neurons in mammals. Previous studies have shown that the negative feedback mechanism is disrupted in global Gpr54-null mutants. The present investigation aimed to determine (1) if a lack of cyclical estrogen exposure of the GnRH neuronal network in the life-long hypogonadotropic Gpr54-null mice contributed to their failed negative feedback mechanism and (2) the cellular location of disrupted kisspeptin-Gpr54 signaling. Plasma luteinizing hormone (LH) concentrations were determined in individual adult female mice when intact, following ovariectomy (OVX) and in response to an acute injection of 17β-estradiol (E2). Control mice exhibited a characteristic rise in LH after OVX that was suppressed by acute E2. Global Gpr54-null mice failed to exhibit any post-OVX increase in LH or response to E2. Adult female global Gpr54-null mice given a cyclical regimen of estradiol for three cycles prior to OVX also failed to exhibit any post-OVX increase in LH or response to E2. To address whether Gpr54 signaling at the GnRH neuron itself was necessary for the failed response to OVX in global Gpr54-null animals, adult female mice with a GnRH neuron-selective deletion of Gpr54 were examined. These mice also failed to exhibit any post-OVX increase in LH or response to E2. These experiments demonstrate defective negative feedback in global Gpr54-null mice that cannot be attributed to a lack of prior exposure of the GnRH neuronal network to cyclical estradiol. The absence of negative feedback in GnRH neuron-selective Gpr54-null mice demonstrates the necessity of direct kisspeptin signaling at the GnRH neuron for this mechanism to occur.
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Affiliation(s)
- Shel-Hwa Yeo
- Centre for Neuroendocrinology, Department of Physiology, School of Medical Sciences, University of Otago, Dunedin, New Zealand
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98
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Grachev P, Millar RP, O'Byrne KT. The role of neurokinin B signalling in reproductive neuroendocrinology. Neuroendocrinology 2014; 99:7-17. [PMID: 24356581 DOI: 10.1159/000357734] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/04/2013] [Indexed: 11/19/2022]
Abstract
The KNDy neuropeptides, kisspeptin, neurokinin B (NKB) and dynorphin A (Dyn), have been implicated in regulating pulsatile luteinising hormone (LH) secretion. Studies of the interactions between KNDy signalling systems, however, are currently few. Although the stimulatory effect of kisspeptin and the inhibitory effect of Dyn on the gonadotropin-releasing hormone pulse generator are widely accepted, the effects of NKB in rodents are variable and sometimes controversial. Literature describing increased LH secretion in response to NKB receptor agonism predominates and is in line with human physiology, as well as the pathophysiology of pubertal failure associated with disruption of NKB signalling. However, the robust suppression of the LH pulse, induced by the same treatment under hypoestrogenic conditions, may hold clues as to the mechanisms of reproductive inhibition under pathological conditions. This review discusses the recent evidence for this paradox and outlines a revised working model incorporating the mechanisms by which KNDy neuropeptides modulate the reproductive axis.
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Affiliation(s)
- P Grachev
- Division of Women's Health, School of Medicine, King's College London, London, UK
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99
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Hu J, Du G, Zhang W, Huang H, Chen D, Wu D, Wang X. Short-term neonatal/prepubertal exposure of dibutyl phthalate (DBP) advanced pubertal timing and affected hypothalamic kisspeptin/GPR54 expression differently in female rats. Toxicology 2013; 314:65-75. [DOI: 10.1016/j.tox.2013.09.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 11/29/2022]
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100
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Abstract
This paper is the thirty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2012 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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