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Zhang K, Zhao L, Bin Y, Guo M, Zhou X, Li M, Han L, Li Q. Serum prolactin and gonadal hormones in hemodialysis women: a meta-analysis. BMC Endocr Disord 2023; 23:203. [PMID: 37749539 PMCID: PMC10518945 DOI: 10.1186/s12902-023-01452-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 09/08/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUND A meta-analysis followed by PRISMA 2020 statement was performed aiming to present a whole prolactin and sex hormone profile in hemodialysis women. METHODS Literatures were searched in PubMed, Cochrane library, Embase, and Web of science before March 11, 2023. Trial sequential analysis (TSA) was performed to test the conclusiveness of this meta-analysis. Egger's test and trim-and-fill analysis was used to test publication bias. We took standardized mean difference (SMD) as pool effect of hormones values including prolactin (PRL), follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2) and progesterone (P). This study was registered in PROSPERO and the number was CRD42023394503. RESULTS Twenty-two articles from 13 countries were analyzed. Combining the results of TSA and meta-analysis, we found that compared with healthy control, hemodialysis women had higher PRL, follicular FSH and LH values and lower P levels (PRL: I2 = 87%, SMD 1.24, 95% CI: 0.79-1.69, p < 0.00001; FSH: I2 = 0%, SMD 0.34, 95% CI: 0.13-0.55, p = 0.002; LH: I2 = 39%, SMD 0.64, 95% CI: 0.34-0.93, p < 0.00001; P: I2 = 30%, SMD - 1.62, 95% CI: -2.04 to -1.20, p < 0.00001). What's more, compared with women after renal transplantation, hemodialysis women had higher PRL levels (I2 = 0%, SMD 0.51, 95% CI: 0.25-0.78, p = 0.0001). There was not enough evidence to draw a conclusion on the comparison of hormones between regular and irregular menses hemodialysis women. Egger's test and trim-and-fill analysis didn't show significant publication bias. CONCLUSIONS Hemodialysis women had higher serum PRL, follicular phase FSH, LH and lower serum P values compared with healthy control. PRL values of hemodialysis women were also higher than that of women after renal transplantation.
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Affiliation(s)
- Kailu Zhang
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Lanbo Zhao
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Yadi Bin
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Miao Guo
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Xue Zhou
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Min Li
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Lu Han
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Qiling Li
- Department of Obstetrics and Gynecology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China.
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Farrar VS, Flores L, Viernes RC, Ornelas Pereira L, Mushtari S, Calisi RM. Prolactin promotes parental responses and alters reproductive axis gene expression, but not courtship behaviors, in both sexes of a biparental bird. Horm Behav 2022; 144:105217. [PMID: 35785711 DOI: 10.1016/j.yhbeh.2022.105217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 05/16/2022] [Accepted: 06/20/2022] [Indexed: 11/16/2022]
Abstract
Prolactin, a hormone involved in vertebrate parental care, is hypothesized to inhibit reproductive hypothalamic-pituitary-gonadal (HPG) axis activity during parenting, thus maintaining investment in the current brood as opposed to new reproductive efforts. While prolactin underlies many parental behaviors in birds, its effects on other reproductive behaviors, such as courtship, remain unstudied. How prolactin affects neuropeptide and hormone receptor expression across the avian HPG axis also remains unknown. To address these questions, we administered ovine prolactin (oPRL) or a vehicle control to both sexes in experienced pairs of the biparental rock dove (Columba livia), after nest removal at the end of incubation. We found that oPRL promoted parental responses to novel chicks and stimulated crop growth compared to controls, consistent with other studies. However, we found that neither courtship behaviors, copulation rates nor pair maintenance differed with oPRL treatment. Across the HPG, we found oPRL had little effect on gene expression in hypothalamic nuclei, but increased expression of FSHB and hypothalamic hormone receptor genes in the pituitary. In the gonads, oPRL increased testes size and gonadotropin receptor expression, but did not affect ovarian state or small white follicle gene expression. However, the oviducts of oPRL-treated females were smaller and had lower estrogen receptor expression compared with controls. Our results highlight that some species, especially those that show multiple brooding, may continue to express mating behavior despite elevated prolactin. Thus, mechanisms may exist for prolactin to promote investment in parental care without concurrent inhibition of reproductive function or HPG axis activity.
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Affiliation(s)
- Victoria S Farrar
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, United States of America.
| | - Laura Flores
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, United States of America
| | - Rechelle C Viernes
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, United States of America
| | - Laura Ornelas Pereira
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, United States of America
| | - Susan Mushtari
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, United States of America
| | - Rebecca M Calisi
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA 95616, United States of America
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3
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Al-Kuraishy HM, Al-Gareeb AI, Butnariu M, Batiha GES. The crucial role of prolactin-lactogenic hormone in Covid-19. Mol Cell Biochem 2022; 477:1381-1392. [PMID: 35147901 PMCID: PMC8831165 DOI: 10.1007/s11010-022-04381-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 01/27/2022] [Indexed: 12/15/2022]
Abstract
Prolactin (PRL) is a peptide hormone secreted from anterior pituitary involved in milk production in the females and regulation of sex drive in both sexes. PRL has pro-inflammatory and anti-inflammatory functions. High PRL serum level or hyperprolactinemia is associated with different viral infections. In coronavirus disease 2019 (Covid-19), which caused by positive-sense single-strand RNA virus known as severe acute respiratory distress syndrome coronavirus type 2 (SARS-CoV-2), PRL serum level is increased. PRL in Covid-19 may exacerbate the underlying inflammatory status by induction release of pro-inflammatory cytokines. However, PRL through its anti-inflammatory effects may reduce the hyperinflammatory status in Covid-19. The underlying mechanism of increasing PRL in Covid-19 is poorly understood. Therefore, in this review we try to find the potential anti-inflammatory or pro-inflammatory role of PRL in Covid-19. As well, this review was aimed to discuss the underlying causes and mechanisms for Covid-19-induced hyperprolactinemia.
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Affiliation(s)
| | - Ali I Al-Gareeb
- College of Medicine, Al-Mustansiriyah University, P.O. Box 14132, Baghdad, Iraq
| | - Monica Butnariu
- Chemistry & Biochemistry Discipline, Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" From Timisoara, Calea Aradului 119, 300645, Timis, Romania.
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, AlBeheira, 22511, Egypt.
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4
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Farrar VS, Harris RM, Austin SH, Nava Ultreras BM, Booth AM, Angelier F, Lang AS, Feustel T, Lee C, Bond A, MacManes MD, Calisi RM. Prolactin and prolactin receptor expression in the HPG axis and crop during parental care in both sexes of a biparental bird (Columba livia). Gen Comp Endocrinol 2022; 315:113940. [PMID: 34756919 DOI: 10.1016/j.ygcen.2021.113940] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 10/11/2021] [Accepted: 10/22/2021] [Indexed: 12/31/2022]
Abstract
During breeding, multiple circulating hormones, including prolactin, facilitate reproductive transitions in species that exhibit parental care. Prolactin underlies parental behaviors and related physiological changes across many vertebrates, including birds and mammals. While circulating prolactin levels often fluctuate across breeding, less is known about how relevant target tissues vary in their prolactin responsiveness via prolactin receptor (PRLR) expression. Recent studies have also investigated prolactin (PRL) gene expression outside of the pituitary (i.e., extra-pituitary PRL), but how PRL gene expression varies during parental care in non-pituitary tissue (e.g., hypothalamus, gonads) remains largely unknown. Further, it is unclear if and how tissue-specific PRL and PRLR vary between the sexes during biparental care. To address this, we measured PRL and PRLR gene expression in tissues relevant to parental care, the endocrine reproductive hypothalamic-pituitary- gonadal (HPG) axis and the crop (a tissue with a similar function as the mammalian mammary gland), across various reproductive stages in both sexes of a biparental bird, the rock dove (Columba livia). We also assessed how these genes responded to changes in offspring presence by adding chicks mid-incubation, simulating an early hatch when prolactin levels were still moderately low. We found that pituitary PRL expression showed similar increases as plasma prolactin levels, and detected extra-pituitary PRL in the hypothalamus, gonads and crop. Hypothalamic and gonadal PRLR expression also changed as birds began incubation. Crop PRLR expression correlated with plasma prolactin, peaking when chicks hatched. In response to replacing eggs with a novel chick mid-incubation, hypothalamic and gonadal PRL and PRLR gene expression differed significantly compared to mid-incubation controls, even when plasma prolactin levels did not differ. We also found sex differences in PRL and PRLR that suggest gene expression may allow males to compensate for lower levels in prolactin by upregulating PRLR in all tissues. Overall, this study advances our understanding of how tissue-specific changes in responsiveness to parental hormones may differ across key reproductive transitions, in response to offspring cues, and between the sexes.
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Affiliation(s)
- Victoria S Farrar
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States.
| | - Rayna M Harris
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - Suzanne H Austin
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - Brandon M Nava Ultreras
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - April M Booth
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - Frédéric Angelier
- Centre d'Etudes Biologiques de Chizé, CNRS, UMR 7372, 79360 Villiers en Bois, France
| | - Andrew S Lang
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, United States
| | - Tanner Feustel
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - Candice Lee
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - Annie Bond
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
| | - Matthew D MacManes
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, United States
| | - Rebecca M Calisi
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA 95616, United States
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5
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Corona R, Jayakumar P, Carbajo Mata MA, Del Valle-Díaz MF, Luna-García LA, Morales T. Sexually dimorphic effects of prolactin treatment on the onset of puberty and olfactory function in mice. Gen Comp Endocrinol 2021; 301:113652. [PMID: 33122037 DOI: 10.1016/j.ygcen.2020.113652] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 10/19/2020] [Accepted: 10/22/2020] [Indexed: 11/28/2022]
Abstract
The onset of puberty is associated with the psychophysiological maturation of the adolescent to an adult capable of reproduction when olfactory signals play an important role. This period begins with the secretion of the gonadotropin-releasing hormone (GnRH) from GnRH neurons within the hypothalamus. This is regulated by kisspeptin neurons that express high levels of transmembrane prolactin receptors (PRLR) that bind to and are activated by prolactin (PRL). The elevated levels of serum PRL found during lactation, or caused by chronic PRL infusion, decreases the secretion of gonadotropins and kisspeptin and compromised the estrous cyclicity and the ovulation. In the present work, we aimed to evaluate the effects of either increased or decreased PRL circulating levels within the peripubertal murine brain by administration of PRL or treatment with cabergoline (Cab) respectively. We showed that either treatment delayed the onset of puberty in females, but not in males. This was associated with the augmentation of the PRL receptor (Prlr) mRNA expression in the arcuate nucleus and decreased Kiss1 expression in the anteroventral periventricular zone. Then, during adulthood, we assessed the activation of the mitral and granular cells of the main (MOB) and accessory olfactory bulb (AOB) by cFos immunoreactivity (ir) after the exposure to soiled bedding of the opposite sex. In the MOB, the PRL treatment promoted an increased cFos-ir of the mitral cells of males and females. In the granular cells of male of either treatment an augmented activation was observed. In the AOB, an impaired cFos-ir was observed in PRL and Cab treated females after exposure to male soiled bedding. However, in males, only Cab impaired its activation. No effects were observed in the AOB-mitral cells. In conclusion, our results demonstrate that PRL contributes to pubertal development and maturation of the MOB-AOB during the murine juvenile period in a sex-dependent way.
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Affiliation(s)
- Rebeca Corona
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico.
| | - Preethi Jayakumar
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico
| | | | | | | | - Teresa Morales
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico
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6
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Chen Y, Wang X, Yang C, Liu Q, Ran Z, Li X, He C. A mouse model reveals the events and underlying regulatory signals during the gonadotrophin-dependent phase of follicle development. Mol Hum Reprod 2020; 26:920-937. [PMID: 33063120 DOI: 10.1093/molehr/gaaa069] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/07/2020] [Indexed: 12/13/2022] Open
Abstract
During folliculogenesis, the gonadotrophin (GTH)-dependent phase begins at the small antral follicle stage and ends with Graafian follicles. In this study, pregnant mare's serum GTH was used to induce GTH-dependent folliculogenesis in mice, following which the developmental events that follicles undergo, as well as the underlying regulatory signals, were investigated at both the morphological and transcriptomic level. GTH-dependent folliculogenesis consisted of three phases: preparation, rapid growth and decelerated growth. In the preparation phase, comprising the first 12 h, granulosa cells completed the preparations for proliferation and differentiation, shifted energy metabolism to glycolysis, and reduced protein synthesis and processing. The rapid growth phase lasted from 12 to 24 h; in this phase, granulosa cells completed their proliferation, and follicles acquired the capacity for estradiol secretion and ovulation. Meanwhile, the decelerating growth phase occurred between 24 and 48 h of GTH-dependent folliculogenesis. In this phase, the proliferation and expansion of the follicular antrum were reduced, energy metabolism was shifted to oxidative phosphorylation, and cell migration and lipid metabolism were enhanced in preparation for luteinization. We also revealed the key signaling pathways that regulate GTH-dependent folliculogenesis and elucidated the activation sequence of these pathways. A comparison of our RNA-sequencing data with that reported for humans suggested that the mechanisms involved in mouse and human folliculogenesis are evolutionarily conserved. In this study, we draw a detailed atlas of GTH-dependent folliculogenesis, thereby laying the foundation for further investigation of the regulatory mechanisms underlying this process.
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Affiliation(s)
- Yingjun Chen
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Xiaodong Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Chan Yang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Qinghua Liu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Zaohong Ran
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Xiang Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Changjiu He
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,National Center for International Research on Animal Genetics, Breeding and reproduction, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
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7
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Phillipps HR, Yip SH, Grattan DR. Patterns of prolactin secretion. Mol Cell Endocrinol 2020; 502:110679. [PMID: 31843563 DOI: 10.1016/j.mce.2019.110679] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 12/06/2019] [Accepted: 12/06/2019] [Indexed: 12/11/2022]
Abstract
Prolactin is pleotropic in nature affecting multiple tissues throughout the body. As a consequence of the broad range of functions, regulation of anterior pituitary prolactin secretion is complex and atypical as compared to other pituitary hormones. Many studies have provided insight into the complex hypothalamic-pituitary networks controlling prolactin secretion patterns in different species using a range of techniques. Here, we review prolactin secretion in both males and females; and consider the different patterns of prolactin secretion across the reproductive cycle in representative female mammals with short versus long luteal phases and in seasonal breeders. Additionally, we highlight changes in the pattern of secretion during pregnancy and lactation, and discuss the wide range of adaptive functions that prolactin may have in these important physiological states.
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Affiliation(s)
- Hollian R Phillipps
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand
| | - Siew H Yip
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand
| | - David R Grattan
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand.
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Ladyman SR, Hackwell ECR, Brown RSE. The role of prolactin in co-ordinating fertility and metabolic adaptations during reproduction. Neuropharmacology 2019; 167:107911. [PMID: 32058177 DOI: 10.1016/j.neuropharm.2019.107911] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/05/2019] [Accepted: 12/09/2019] [Indexed: 12/30/2022]
Abstract
Mammalian pregnancy and lactation is accompanied by a period of infertility that takes place in the midst of a sustained increase in food intake. Indeed, successful reproduction in females is dependent on co-ordination of the distinct systems that regulate reproduction and metabolism. Rather than arising from different mechanisms during pregnancy and lactation, we propose that elevations in lactogenic hormones (predominant among these being prolactin and the placental lactogens), are ideally placed to influence both of these systems at the appropriate time. We review the literature examining the impacts of lactogens on fertility and energy homeostasis in the virgin state, during pregnancy and lactation and potential long-term impacts of reproductive experience. Taken together, the literature indicates that duration and pattern of lactogen exposure is a vital factor in the ability of these hormones to alter reproduction and food intake. Transient increases in prolactin, as typically seen in healthy virgin females and males, are unable to exert lasting impacts. Importantly, both suppression of fertility and increased food intake are only observed following exposure to chronically-elevated levels of lactogens. Physiologically, the only time this pattern of lactogenic secretion is maintained in the healthy female is during pregnancy and lactation, when co-ordination between these regulatory systems emerges. This article is part of the special issue on 'Neuropeptides'.
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Affiliation(s)
- Sharon R Ladyman
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Eleni C R Hackwell
- Centre for Neuroendocrinology and Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Rosemary S E Brown
- Centre for Neuroendocrinology and Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.
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