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Yun SJ, Sang H, Park SY, Chin SO. Effect of Hyperprolactinemia on Bone Metabolism: Focusing on Osteopenia/Osteoporosis. Int J Mol Sci 2024; 25:1474. [PMID: 38338751 PMCID: PMC10855748 DOI: 10.3390/ijms25031474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 02/12/2024] Open
Abstract
Prolactin is a hormone secreted from lactotroph cells in the anterior pituitary gland to induce lactation after birth. Hyperprolactinemia unrelated to lactation is a common cause of amenorrhea in women of a childbearing age, and a consequent decrease in the gonadotropin-releasing hormone (GnRH) by a high prolactin level can result in decreased bone mineral density. Osteoporosis is a common skeletal disorder characterized by decreased bone mineral density (BMD) and quality, which results in decreased bone strength. In patients with hyperprolactinemia, changes in BMD can be induced indirectly by the inhibition of the GnRH-gonadal axis due to increased prolactin levels or by the direct action of prolactin on osteoblasts and, possibly, osteoclast cells. This review highlights the recent work on bone remodeling and discusses our knowledge of how prolactin modulates these interactions, with a brief literature review on the relationship between prolactin and bone metabolism and suggestions for new possibilities.
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Affiliation(s)
| | | | | | - Sang Ouk Chin
- Department of Endocrinology and Metabolism, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul 02447, Republic of Korea; (S.J.Y.); (H.S.); (S.Y.P.)
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2
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Uenoyama Y, Inoue N, Tsukamura H. Kisspeptin and lactational anestrus: Current understanding and future prospects. Peptides 2023; 166:171026. [PMID: 37230188 DOI: 10.1016/j.peptides.2023.171026] [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: 03/03/2023] [Revised: 05/18/2023] [Accepted: 05/22/2023] [Indexed: 05/27/2023]
Abstract
Lactational anestrus, characterized by the suppression of pulsatile gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) release, would be a strategic adaptation to ensure survival by avoiding pregnancy during lactation in mammals. In the present article, we first provide a current understanding of the central regulation of reproduction in mammals, i.e., a fundamental role of arcuate kisspeptin neurons in mammalian reproduction by driving GnRH/LH pulses. Second, we discuss the central mechanism inhibiting arcuate Kiss1 (encoding kisspeptin) expression and GnRH/LH pulses during lactation with a focus on suckling stimulus, negative energy balance due to milk production, and the role of circulating estrogen in rats. We also discuss upper regulators that control arcuate kisspeptin neurons in rats during the early and late lactation periods based on the findings obtained by a lactating rat model. Finally, we discuss potential reproductive technology for the improvement of reproductive performance in milking cows.
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Affiliation(s)
- Yoshihisa Uenoyama
- Laboratory of Animal Reproduction, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
| | - Naoko Inoue
- Laboratory of Animal Reproduction, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Hiroko Tsukamura
- Laboratory of Animal Reproduction, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
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3
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Duarte JCG, Ferreira JGP, Bittencourt JC. The effect of estrogen and progesterone on melanin-concentrating hormone producing-neurons in brain areas related to reproductive behavior in lactating dams. J Chem Neuroanat 2023; 128:102208. [PMID: 36476756 DOI: 10.1016/j.jchemneu.2022.102208] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
The hypothalamus plays a role in reproductive cycle control, and it is a site of action of steroid hormones. Throughout the production of melanin-concentrating hormone (MCH), the hypothalamus shows adaptive changes during lactation. Therefore, in this work, we aimed to test the effects of estrogen and progesterone manipulation on MCH-immunoreactive (ir) neurons in hypothalamic brain areas related to reproductive behavior and on the MCH serum concentration. Our results show that the removal of steroid hormones by ovariectomy increases the number of MCH-ir neurons in the medial preoptic area (MPOA) and incerto-hypothalamic area (IHy) but not in the anterior part of the paraventricular nucleus of the hypothalamus (PVHa). The MCH in the serum levels also increases. In accordance, the injection of estradiol alone or estradiol and progesterone decreased the number of MCH-ir neurons in the MPOA and IHy, as well as its serum levels. The MPOA and IHy are the brain areas targeted by the steroid hormone inhibitory effect of the MCH system during lactation. This effect is also reflected in the MCH serum levels.
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Affiliation(s)
- Jessica Catharine Gomes Duarte
- Laboratory of Chemical Neuroanatomy, Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Jozelia Gomes Pacheco Ferreira
- Laboratory of Chemical Neuroanatomy, Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Jackson Cioni Bittencourt
- Laboratory of Chemical Neuroanatomy, Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
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4
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Athonvarangkul D, Wysolmerski JJ. Crosstalk within a brain-breast-bone axis regulates mineral and skeletal metabolism during lactation. Front Physiol 2023; 14:1121579. [PMID: 36875035 PMCID: PMC9979219 DOI: 10.3389/fphys.2023.1121579] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 01/27/2023] [Indexed: 02/18/2023] Open
Abstract
To support the increased calcium demands for milk production during lactation, a dramatic and reversible physiological response occurs to alter bone and mineral metabolism. This coordinated process involves a brain-breast-bone axis that integrates hormonal signals that allow for adequate calcium delivery to milk yet also protects the maternal skeletal from excessive bone loss or decreases in bone quality or function. Here, we review the current knowledge on the crosstalk between the hypothalamus, mammary gland, and skeleton during lactation. We discuss the rare entity of pregnancy and lactation associated osteoporosis and consider how the physiology of bone turnover in lactation may impact the pathophysiology of postmenopausal osteoporosis. Further understanding of the regulators of bone loss during lactation, particularly in humans, may provide insights into new therapies for osteoporosis and other diseases of excess bone loss.
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Affiliation(s)
- Diana Athonvarangkul
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
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Calik-Ksepka A, Stradczuk M, Czarnecka K, Grymowicz M, Smolarczyk R. Lactational Amenorrhea: Neuroendocrine Pathways Controlling Fertility and Bone Turnover. Int J Mol Sci 2022; 23:ijms23031633. [PMID: 35163554 PMCID: PMC8835773 DOI: 10.3390/ijms23031633] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/28/2022] [Accepted: 01/28/2022] [Indexed: 02/06/2023] Open
Abstract
Lactation is a physiological state of hyperprolactinemia and associated amenorrhea. Despite the fact that exact mechanisms standing behind the hypothalamus-pituitary-ovarian axis during lactation are still not clear, a general overview of events leading to amenorrhea may be suggested. Suckling remains the most important stimulus maintaining suppressive effect on ovaries after pregnancy. Breastfeeding is accompanied by high levels of prolactin, which remain higher than normal until the frequency and duration of daily suckling decreases and allows normal menstrual function resumption. Hyperprolactinemia induces the suppression of hypothalamic Kiss1 neurons that directly control the pulsatile release of GnRH. Disruption in the pulsatile manner of GnRH secretion results in a strongly decreased frequency of corresponding LH pulses. Inadequate LH secretion and lack of pre-ovulatory surge inhibit the progression of the follicular phase of a menstrual cycle and result in anovulation and amenorrhea. The main consequences of lactational amenorrhea are connected with fertility issues and increased bone turnover. Provided the fulfillment of all the established conditions of its use, the lactational amenorrhea method (LAM) efficiently protects against pregnancy. Because of its accessibility and lack of additional associated costs, LAM might be especially beneficial in low-income, developing countries, where modern contraception is hard to obtain. Breastfeeding alone is not equal to the LAM method, and therefore, it is not enough to successfully protect against conception. That is why LAM promotion should primarily focus on conditions under which its use is safe and effective. More studies on larger study groups should be conducted to determine and confirm the impact of behavioral factors, like suckling parameters, on the LAM efficacy. Lactational bone loss is a physiologic mechanism that enables providing a sufficient amount of calcium to the newborn. Despite the decline in bone mass during breastfeeding, it rebuilds after weaning and is not associated with a postmenopausal decrease in BMD and osteoporosis risk. Therefore, it should be a matter of concern only for lactating women with additional risk factors or with low BMD before pregnancy. The review summarizes the effect that breastfeeding exerts on the hypothalamus-pituitary axis as well as fertility and bone turnover aspects of lactational amenorrhea. We discuss the possibility of the use of lactation as contraception, along with this method's prevalence, efficacy, and influencing factors. We also review the literature on the topic of lactational bone loss: its mechanism, severity, and persistence throughout life.
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Affiliation(s)
- Anna Calik-Ksepka
- Department of Gynaecological Endocrinology, Medical University of Warsaw, Karowa 2, 00-315 Warsaw, Poland; (M.G.); (R.S.)
- Correspondence:
| | - Monika Stradczuk
- Student’s Academic Association, Department of Gynecological Endocrinology, Faculty of Medicine, Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland; (M.S.); (K.C.)
| | - Karolina Czarnecka
- Student’s Academic Association, Department of Gynecological Endocrinology, Faculty of Medicine, Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland; (M.S.); (K.C.)
| | - Monika Grymowicz
- Department of Gynaecological Endocrinology, Medical University of Warsaw, Karowa 2, 00-315 Warsaw, Poland; (M.G.); (R.S.)
| | - Roman Smolarczyk
- Department of Gynaecological Endocrinology, Medical University of Warsaw, Karowa 2, 00-315 Warsaw, Poland; (M.G.); (R.S.)
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Alsharairi NA. The Role of Short-Chain Fatty Acids in Mediating Very Low-Calorie Ketogenic Diet-Infant Gut Microbiota Relationships and Its Therapeutic Potential in Obesity. Nutrients 2021; 13:3702. [PMID: 34835958 PMCID: PMC8624546 DOI: 10.3390/nu13113702] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 12/13/2022] Open
Abstract
As the very low-calorie ketogenic diet (VLCKD) gains increased interest as a therapeutic approach for many diseases, little is known about its therapeutic use in childhood obesity. Indeed, the role of VLCKD during pregnancy and lactation in influencing short chain fatty acid (SCFA)-producing bacteria and the potential mechanisms involved in the protective effects on obesity are still unclear. Infants are characterized by a diverse gut microbiota composition with higher abundance of SCFA-producing bacteria. Maternal VLCKD during pregnancy and lactation stimulates the growth of diverse species of SCFA-producing bacteria, which may induce epigenetic changes in infant obese gene expression and modulate adipose tissue inflammation in obesity. Therefore, this review aims to determine the mechanistic role of SCFAs in mediating VLCKD-infant gut microbiota relationships and its protective effects on obesity.
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Affiliation(s)
- Naser A Alsharairi
- Heart, Mind & Body Research Group, Griffith University, Gold Coast, QLD 4222, Australia
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7
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Tan S, Zhou Y, Zhao H, Wu J, Yu H, Yang Y, Yang Y, Zhao H, Li H. Comprehensive transcriptome analysis of hypothalamus reveals genes associated with disorders of sex development in pigs. J Steroid Biochem Mol Biol 2021; 210:105875. [PMID: 33746111 DOI: 10.1016/j.jsbmb.2021.105875] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 12/14/2022]
Abstract
XX sex reversal, also called XX disorders of sex development (XX-DSD), is a condition affecting the development of the gonads or genitalia, and is relatively common in pigs. However, its genetic etiology and transcriptional regulation mechanism in the hypothalamic-pituitary-gonadal axis (HPGA) remain mostly unknown. XX-DSD (SRY-negative) pigs and normal sows were selected by external genitalia observation. The hypothalamus, which is the integrated center of the HPGA was sampled for whole-transcriptome RNA-seq. The role of DEmiRNA was validated by its overexpression and knockdown in vitro. A total of 1,258 lncRNAs, 1,086 mRNAs, and 61 microRNAs differentially expressed in XX-DSD pigs compared with normal female pigs. Genes in the hormone biosynthesis and secretion pathway significantly up-regulated, and the up-regulation of GNRH1, KISS1 and AVP may associate with the abnormal secretion of GnRH. We also predicted the lncRNA-miRNA-mRNA co-expression triplets and constructed three competing endogenous RNA (ceRNA) potentially associated with XX-DSD. Functional enrichment studies suggested that TCONS_00340886, TCONS_00000204 and miR-181a related to GnRH secretion. Further, miR-181a inhibitor up-regulated GNRH1, PAK6, and CAMK4 in the GT1-7 cells. Conversely, transfection of miR-181a mimics obtained the opposite trends. The expression levels of FSHR, LHR, ESR1 and ESR2 were significantly higher in XX-DSD gondas than those in normal sows. Taken together, we proposed that the balance of endocrine had broken in XX-DSD pigs. The current study is the first to examine the transcriptomic profile in the hypothalamus of XX-DSD pigs. It provides new insight into coding and non-coding RNAs that may be associated with DSD in pigs.
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Affiliation(s)
- Shuwen Tan
- Department of Ecology, Tibetan Centre for Ecology and Conservation at WHU-TU, Hubei Key Laboratory of Cell Homeostasis, College of Life Science, Wuhan University, Wuhan 430072, China; Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China
| | - Yi Zhou
- College of Basic Medicine, Zunyi Medical University, Zunyi 563006, China
| | - Haiquan Zhao
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China
| | - Jinhua Wu
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China
| | - Hui Yu
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China
| | - Yin Yang
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China
| | - Yalan Yang
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China
| | - Huabin Zhao
- Department of Ecology, Tibetan Centre for Ecology and Conservation at WHU-TU, Hubei Key Laboratory of Cell Homeostasis, College of Life Science, Wuhan University, Wuhan 430072, China; College of Science, Tibet University, Lhasa 850000, China.
| | - Hua Li
- Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, School of Life Science and Engineering, Foshan University, Foshan 528225, China.
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Marín-Garzón NA, Magalhães AFB, Schmidt PI, Serna M, Fonseca LFS, Salatta BM, Frezarim GB, Fernandes-Júnior GA, Bresolin T, Carvalheiro R, Albuquerque LG. Genome-wide scan reveals genomic regions and candidate genes underlying direct and maternal effects of preweaning calf mortality in Nellore cattle. Genomics 2021; 113:1386-1395. [PMID: 33716185 DOI: 10.1016/j.ygeno.2021.02.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/25/2021] [Accepted: 02/23/2021] [Indexed: 11/26/2022]
Abstract
We conducted analysis to estimate genetic parameters and to identify genomic regions and candidate genes affecting direct and maternal effects of preweaning calf mortality (PWM) in Nellore cattle. Phenotypic records of 67,196 animals, and 8443 genotypes for 410,936 SNPs were used. Analysis were performed through the weighted single-step GBLUP approach and considering a threshold animal model via Bayesian Inference. Direct and maternal heritability estimates were of 0.2143 ± 0.0348 and 0.0137 ± 0.0066, respectively. The top 10 genomic regions accounted for 13.61 and 14.23% of the direct and maternal additive genetic variances and harbored a total of 63 and 91 positional candidate genes, respectively. Two overlapping regions on BTA2 were identified for both direct and maternal effects. Candidate genes are involved in biological mechanisms i.e. embryogenesis, immune response, feto-maternal communication, circadian rhythm, hormone alterations, myometrium adaptation, and milk secretion, which are critical for the successful calf growth and survival during preweaning period.
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Affiliation(s)
- N A Marín-Garzón
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil.
| | - A F B Magalhães
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - P I Schmidt
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - M Serna
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - L F S Fonseca
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - B M Salatta
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - G B Frezarim
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - G A Fernandes-Júnior
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - T Bresolin
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - R Carvalheiro
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil
| | - L G Albuquerque
- São Paulo State University (Unesp), College of Agricultural and Veterinarian Sciences, Via de Acesso Professor Paulo Donato Castelane Castellane S/N - Vila Industrial, 14884-900 Jaboticabal, SP, Brazil; National Council for Science and Technological Development (CNPq), Brasília, Brazil
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9
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Sex differences in behavioral and metabolic effects of gene inactivation: The neuropeptide Y and Y receptors in the brain. Neurosci Biobehav Rev 2020; 119:333-347. [PMID: 33045245 DOI: 10.1016/j.neubiorev.2020.09.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 02/06/2023]
Abstract
Brain and gonadal hormones interplay controls metabolic and behavioral functions in a sex-related manner. However, most translational neuroscience research related to animal models of endocrine and psychiatric disorders are often carried out in male animals only. The Neuropeptide Y (NPY) system shows sex-dependent differences and is sensitive to gonadal steroids. Based on published data from our and other laboratories, in this review we will discuss the sex related differences of NPY action on energy balance, bone homeostasis and behavior in rodents with the genetic manipulation of genes encoding NPY and its Y1, Y2 and Y5 cognate receptors. Comparative analyses of the phenotype of transgenic and knockout NPY and Y receptor rodents unravels sex dependent differences in the functions of this neurotransmission system, potentially helping to develop therapeutics for a variety of sex-related disorders including metabolic syndrome, osteoporosis and ethanol addiction.
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Scarola S, Kent M, Neal S, Trejo JP, Bardi M, Lambert K. Postpartum environmental challenges alter maternal responsiveness and offspring development. Horm Behav 2020; 122:104761. [PMID: 32330549 DOI: 10.1016/j.yhbeh.2020.104761] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 04/11/2020] [Accepted: 04/17/2020] [Indexed: 12/21/2022]
Abstract
Because many threats exist in an animal's natural habitat, it is important to understand the impact of environmental challenges on maternal-offspring interactions and outcomes. In the current study, a rodent model incorporating the presence of restricted resources and an environmental threat (e.g. predator-related odors and sounds) was investigated. Specifically, pregnant females were assigned to one of four treatments: standard resources, without threat (SR; n = 7); standard resources plus threat (SR-T; n = 8); restricted resources, without threat (RR; n = 7); and restricted resources plus threat (RR-T; n = 6). Maternal rats were moved into the assigned conditions on postnatal day 2 and remained until pups were weaned. Following a standard pup retrieval task on postnatal days 2 and 6, maternal rats were exposed to a retrieval challenge task on postnatal day 8 in which each rat had to traverse a novel barrier to retrieve pups. For neurobiological measures of stress/resilience responsiveness, fecal samples were collected for detection of corticosterone and DHEA metabolites; additionally, immunohistochemistry was conducted on the maternal brains to indicate the presence of Neuropeptide Y (NPY) and Brain Derived Neurotrophic Factor (BDNF) immunoreactivity in the hippocampus, amygdala and hypothalamus. Pup development measures, including body weight and tail length, were also collected. Results suggest that maternal rats with restricted resources exhibited diminished maternal responsiveness that resulted in altered pup development measures; further, restricted resource rats exhibited endocrine markers of compromised emotional resilience (lower DHEA) and decreased neural markers of neuroplasticity (BDNF) and emotional resilience (NPY). Interestingly, predator threat affected various aspects of maternal-pup interactions but had no effect on neurobiological variables, suggesting that restricted resources had a more negative impact on maternal-related outcomes than the presence of predator threat.
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Affiliation(s)
- Samantha Scarola
- Department of Psychology, Behavioral Neuroscience Program, Randolph Macon College, Ashland, VA 23005, USA
| | - Molly Kent
- Department of Biology, Virginia Military Institute, Lexington, VA 25440, USA
| | - Steven Neal
- Department of Psychology, Behavioral Neuroscience Program, Randolph Macon College, Ashland, VA 23005, USA
| | - Jose Perdomo Trejo
- Department of Psychology, Behavioral Neuroscience Program, Randolph Macon College, Ashland, VA 23005, USA
| | - Massimo Bardi
- Department of Psychology, Behavioral Neuroscience Program, Randolph Macon College, Ashland, VA 23005, USA
| | - Kelly Lambert
- Department of Psychology, University of Richmond, Richmond, VA 23173, USA.
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11
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Pereira LCR, Elliott SA, McCargar LJ, Bell RC, Robson PJ, Prado CM. Associations of appetite sensations and metabolic characteristics with weight retention in postpartum women. Appl Physiol Nutr Metab 2020; 45:875-885. [PMID: 32073907 DOI: 10.1139/apnm-2019-0809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Postpartum weight retention (PPWR) is an important risk factor for long-term obesity. Appetite may be a key factor regulating PPWR. The objectives of this study were to determine the associations between (i) PPWR and appetite; and (ii) appetite, lactation, and metabolic characteristics. Data from 49 women at 9 months postpartum contributed to this cross-sectional analysis. Energy expenditure was assessed in a whole-body calorimetry unit for 24 h. Appetite sensations were rated using visual analogue scales. Lactation (min/day) was measured using a 3-day breastfeeding diary. PPWR was negatively associated with fullness (β ± SE; R2 = -2.97 ± 0.72; 0.661; P < 0.001), and satiety (-2.75 ± 0.81; 0.617; P = 0.002), and was positively associated with hunger (2.19 ± 1.02; 0.548; P = 0.039), prospective food consumption (PFC; 2.19 ± 0.91; 0.562; P = 0.021), and composite appetite score (CAS; 0.34 ± 0.09; 0.632; P = 0.001). Lactation was associated with higher CAS (39.68 ± 15.56; 0.365; P = 0.015), hunger (3.56 ± 1.61; 0.308; P = 0.033), and PFC (4.22 ± 1.78; 0.314; P = 0.023), and with reduced sensations of fullness (-4.18 ± 1.94; 0.358; P = 0.038) and satiety (-3.83 ± 1.87; 0.295; P = 0.048). Lactation was associated with appetite, which in turn was related to PPWR. Appetite control should be explored to support postpartum weight management strategies. Novelty Postpartum weight retention was associated with appetite sensations, which were assessed throughout the day under conditions in which energy intake and expenditure were precisely matched. Lactation and other maternal metabolic factors, including carbohydrate oxidation and physical activity level may play a role in controlling appetite during the postpartum period.
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Affiliation(s)
- Leticia C R Pereira
- Department of Agricultural, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, 2-004 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Sarah A Elliott
- Department of Agricultural, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, 2-004 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Linda J McCargar
- Department of Agricultural, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, 2-004 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Rhonda C Bell
- Department of Agricultural, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, 2-004 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Paula J Robson
- Department of Agricultural, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, 2-004 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada.,CancerControl Alberta, Alberta Health Services, Edmonton, AB T5J 3E4, Canada
| | - Carla M Prado
- Department of Agricultural, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, 2-004 Li Ka Shing Center for Health Research Innovation, University of Alberta, Edmonton, AB T6G 2E1, Canada
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12
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Gust K, Caccese C, Larosa A, Nguyen TV. Neuroendocrine Effects of Lactation and Hormone-Gene-Environment Interactions. Mol Neurobiol 2020; 57:2074-2084. [PMID: 31927723 DOI: 10.1007/s12035-019-01855-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 12/11/2019] [Indexed: 12/12/2022]
Abstract
While correlational studies suggest that lactation may confer a certain level of protection from mental illness, this benefit is not uniformly expressed in all women who choose to breastfeed. We propose here that the neuroendocrine "resetting" induced by lactation may predispose toward positive affect states in a subset of hormone-sensitive mothers, with hormone-gene and hormone-environment interactions determining the ultimate psychological outcome. We find evidence to suggest that higher secretion of prolactin/oxytocin as well as lower secretion of vasopression/androgens in lactating mothers may protect against postpartum depression and anxiety, decrease levels of irritability, and optimize stress responses. On the other hand, while the abrupt withdrawal of estradiol/progesterone in the immediate postpartum period tends to be associated with adverse psychological outcomes, the chronic suppression of estrogens/progestogens induced by lactation may have antidepressant and anxiolytic effects over time. Finally, the hypo-cortisolemic state seen in lactating mothers appears to be associated with improved stress reactivity and circadian rhythms. We also discuss hormone-gene and hormone-environment interactions likely to modulate any potential psychological benefits related to lactation and focus on those factors that are either easy to screen for or known to be modifiable. In sum, neuroendocrine alterations induced by lactation may play a key role in determining reproductive psychiatric risk in a subset of hormone-sensitive women. Using these neuroendocrine factors as an individualized index of risk can help in devising targeted programs to support these women in pursuing lactation or, for those not able or willing, accessing psychological interventions in a timely manner.
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Affiliation(s)
- Kirsten Gust
- Reproductive Psychiatry Program, Departments of Psychiatry and Obstetrics-Gynecology, McGill University Health Centre, Montreal, QC, Canada
| | - Christina Caccese
- Department of Psychiatry, McGill University, 1001 Decarie Blvd., Montreal, QC, H4A 3J1, Canada
| | - Amanda Larosa
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada.,Neuroscience Division, Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Tuong-Vi Nguyen
- Reproductive Psychiatry Program, Departments of Psychiatry and Obstetrics-Gynecology, McGill University Health Centre, Montreal, QC, Canada.
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Atteia HH, Alzahrani S, El-Sherbeeny NA, Youssef AM, Farag NE, Mehanna ET, Elhawary R, Ibrahim GA, Elmistekawy A, Zaitone SA. Evening Primrose Oil Ameliorates Hyperleptinemia and Reproductive Hormone Disturbances in Obese Female Rats: Impact on Estrus Cyclicity. Front Endocrinol (Lausanne) 2019; 10:942. [PMID: 32082253 PMCID: PMC7002433 DOI: 10.3389/fendo.2019.00942] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/31/2019] [Indexed: 01/21/2023] Open
Abstract
Obesity is a public health burden disturbing all body functions and reproductive hormones. As obesity increases among females, there will be a rising challenge to physicians in care from fertility problems. Evening primrose oil (EPR oil) contains essential fatty acids including omega-6 linoleic acid with strong anti-inflammatory activity. Since EPR oil has utility in alleviating dysmenorrhea, this study aimed to ascertain its modulatory effect on systemic inflammation, reproductive hormones and estrus cycle irregularity in female obese rats. Thirty-two female rats were distributed to 4 groups: (i) normal, (ii) dietary obese-control female rats, and (iii and iv) dietary obese female rats treated with EPR oil (5 or 10 g/kg). Rats were examined for estrus regularity by taking vaginal smears daily during the last 2 weeks of the experiment. Serum level of insulin, leptin, adiponectin, and inflammatory cytokines was measured. In addition, serum lipid profile, and liver enzyme activities were estimated. Adipose tissues were taken for histopathologic examination as well as determination of gene expression for leptin, leptin receptors, adiponectin, and visfatin. Obese rats exhibited significant weight gain (90.69 ± 8.9), irregular prolonged estrus cycles (83.33%), increased serum levels of insulin, leptin, prolactin and testosterone and decreased gonadotropin levels. EPR oil exhibited a curative effect on obesity-related irregularity in estrus cycle and ovarian pathology. The underlying molecular mechanism may be related to reduction of systemic inflammation, alleviating insulin resistance and modulation of adipokine expression. EPR oil may be considered as a promising therapeutic intervention against obesity-related female hormonal disturbances and estrus irregularity.
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Affiliation(s)
- Hebatallah H. Atteia
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Tabuk, Tabuk, Saudi Arabia
- Department of Biochemistry, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Sharifa Alzahrani
- Pharmacology Department, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia
| | - Nagla A. El-Sherbeeny
- Department of Pharmacology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Amal M. Youssef
- Department of Physiology, Faculty of Medicine, Taibah University, Medina, Saudi Arabia
- Department of Physiology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Noha E. Farag
- Department of Physiology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Eman T. Mehanna
- Department of Biochemistry, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
| | - Reda Elhawary
- Department of Pathology, Faculty of Medicine, Al-Azhar University, Cairo, Egypt
| | - Gehan A. Ibrahim
- Clinical Pathology Department, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Amr Elmistekawy
- Department of Internal Medicine, Gastroenterology Division, Faculty of Medicine, Al-Azhar University, Cairo, Egypt
| | - Sawsan A. Zaitone
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Tabuk, Tabuk, Saudi Arabia
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
- *Correspondence: Sawsan A. Zaitone ;
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14
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Aiken CE, Tarry-Adkins JL, Ashmore TJ, Ozanne SE. Early life environment influences the trajectory of post-partum weight loss in adult female rats. Reprod Biomed Online 2018; 38:779-786. [PMID: 30885667 PMCID: PMC6491499 DOI: 10.1016/j.rbmo.2018.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 09/21/2018] [Accepted: 12/10/2018] [Indexed: 01/09/2023]
Abstract
RESEARCH QUESTION The physiological processes of pregnancy and lactation require profound changes in maternal metabolism and energy balance. The timescale of metabolic reversion after pregnancy, in particular post-partum weight loss, is highly variable between individuals. Currently, mechanisms influencing post-partum metabolic recovery are not well understood. The hypothesis tested here is that, in common with other metabolic and obesity-related outcomes, capacity for post-partum weight loss is influenced by developmental programming. DESIGN Adult female Wistar rats exposed to a maternal low-protein diet in utero then weaned onto a control diet post-natally (recuperated group) were compared with controls. Adult females from both groups underwent pregnancy at 3 months of age. Weight changes and metabolic parameters during pregnancy and lactation were compared between control and recuperated groups, and also with non-pregnant littermates. RESULTS Pregnancy weight gain was not different between the control and recuperated groups, but post-partum recuperated animals remained significantly heavier than both post-partum control animals (P<0.05) and their non-pregnant recuperated littermates (P<0.05) at the end of lactation. Post-partum recuperated animals had more intra-abdominal fat mass (P<0.05) and higher serum triglyceride concentrations (P<0.01) than controls. Post-partum recuperated animals also had increased expression of IL6, NRF2 and ALOX12 (key regulators of inflammation and lipoxygenase activity) in the intra-abdominal adipose tissue compared with control groups. CONCLUSIONS Mothers who themselves have been exposed to adverse early life environments are likely to have slower metabolic recovery from pregnancy than controls. Failure to return to pre-pregnancy weight after delivery predisposes to persisting sequential inter-pregnancy weight gain, which can represent a significant metabolic burden across a life course involving several pregnancies.
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Affiliation(s)
- C E Aiken
- University of Cambridge Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom; Department of Obstetrics and Gynaecology, University of Cambridge, Box 223, The Rosie Hospital and NIHR Cambridge Comprehensive Biomedical Research Centre, Cambridge CB2 0SW, United Kingdom.
| | - J L Tarry-Adkins
- University of Cambridge Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom
| | - T J Ashmore
- University of Cambridge Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom
| | - S E Ozanne
- University of Cambridge Metabolic Research Laboratories and MRC Metabolic Diseases Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom
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15
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Dobolyi A, Cservenák M, Young LJ. Thalamic integration of social stimuli regulating parental behavior and the oxytocin system. Front Neuroendocrinol 2018; 51:102-115. [PMID: 29842887 PMCID: PMC6175608 DOI: 10.1016/j.yfrne.2018.05.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 05/21/2018] [Accepted: 05/25/2018] [Indexed: 12/18/2022]
Abstract
Critically important components of the maternal neural circuit in the preoptic area robustly activated by suckling were recently identified. In turn, suckling also contributes to hormonal adaptations to motherhood, which includes oxytocin release and consequent milk ejection. Other reproductive or social stimuli can also trigger the release of oxytocin centrally, influencing parental or social behaviors. However, the neuronal pathways that transfer suckling and other somatosensory stimuli to the preoptic area and oxytocin neurons have been poorly characterized. Recently, a relay center of suckling was determined and characterized in the posterior intralaminar complex of the thalamus (PIL). Its neurons containing tuberoinfundibular peptide 39 project to both the preoptic area and oxytocin neurons in the hypothalamus. The present review argues that the PIL is a major relay nucleus conveying somatosensory information supporting maternal behavior and oxytocin release in mothers, and may be involved more generally in social cue evoked oxytocin release, too.
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Affiliation(s)
- Arpad Dobolyi
- MTA-ELTE Laboratory of Molecular and Systems Neurobiology, Department of Physiology and Neurobiology, Hungarian Academy of Sciences and Eötvös Loránd University, Budapest, Hungary.
| | - Melinda Cservenák
- MTA-ELTE Laboratory of Molecular and Systems Neurobiology, Department of Physiology and Neurobiology, Hungarian Academy of Sciences and Eötvös Loránd University, Budapest, Hungary; Laboratory of Neuromorphology, Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - Larry J Young
- Center for Translational Social Neuroscience, Silvio O. Conte Center for Oxytocin and Social Cognition, Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Research Center, Emory University, Atlanta, USA.
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16
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Saedi S, Khoradmehr A, Mohammad Reza JS, Tamadon A. The role of neuropeptides and neurotransmitters on kisspeptin/kiss1r-signaling in female reproduction. J Chem Neuroanat 2018; 92:71-82. [PMID: 30008384 DOI: 10.1016/j.jchemneu.2018.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 06/01/2018] [Accepted: 07/02/2018] [Indexed: 01/08/2023]
Abstract
Reproductive function is regulated by the hypothalamic-pituitary-gonads (HPG) axis. Hypothalamic neurons synthesizing kisspeptin play a fundamental role in the central regulation of the timing of puberty onset and reproduction in mammals. Kisspeptin is a regulator of gonadotropin releasing hormone (GnRH) and luteinizing hormone (LH). In female rodent, the kisspeptin (encoded by kiss1 gene), neurokinin B (Tac3) and dynorphin neurons form the basis for the "KNDy neurons" in the arcuate nucleus and play a fundamental role in the regulation of GnRH/LH release. Furthermore, various factors including neurotransmitters and neuropeptides may cooperate with kisspeptin signaling to modulate GnRH function. Many neuropeptides including proopiomelanocortin, neuropeptide Y, agouti-related protein, and other neuropeptides, as well as neurotransmitters, dopamine, norepinephrine and γ-aminobutyric acid are suggested to control feeding and HPG axis, the underlying mechanisms are not well known. Nonetheless, to date, information about the neurochemical factors of kisspeptin neurons remains incomplete in rodent. This review is intended to provide an overview of KNDy neurons; major neuropeptides and neurotransmitters interfere in kisspeptin signaling to modulate GnRH function for regulation of puberty onset and reproduction, with a focus on the female rodent.
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Affiliation(s)
- Saman Saedi
- Department of Animal Science, College of Agriculture, Shiraz University, Shiraz, Iran.
| | - Arezoo Khoradmehr
- Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
| | | | - Amin Tamadon
- The Persian Gulf Marine Biotechnology Research Center, The Persian Gulf Biomedical Sciences Research Institute, Bushehr University of Medical Sciences, Bushehr, Iran.
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17
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Zhang J, Jin PP, Gong M, Yi QT, Zhu RJ. Role of leptin and the leptin receptor in the pathogenesis of varicocele-induced testicular dysfunction. Mol Med Rep 2018; 17:7065-7072. [PMID: 29568885 PMCID: PMC5928662 DOI: 10.3892/mmr.2018.8753] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 03/01/2018] [Indexed: 11/17/2022] Open
Abstract
The present study investigated the expression of leptin and its receptor in the left testis and hypothalamus of rats with varicocele and clarified their roles in the pathogenesis of varicocele-induced testicular dysfunction. A total of 40 male rats were divided randomly into four groups. Groups 1 (G1) and 3 (G3) underwent a sham operation. Groups 2 (G2) and 4 (G4) underwent operations to form a varicocele created by partial ligation of the left renal vein. G1 and G2 rats were euthanized 4 weeks after the operation while G3 and G4 rats were euthanized at 8 weeks. The expression of leptin and its receptor was analyzed by immunohistochemistry. The mRNA levels of leptin, its receptor, kisspeptin (KiSS-1), G-protein coupled receptor 54 (GPR54), gonadotropin releasing hormone (GnRH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured by reverse transcription-quantitative polymerase chain reaction. Testicular spermatogenesis function and gonadal hormone levels were measured. Compared with G1 and G3, the expression of leptin and its receptor in rat testis was significantly higher in G2 and G4, respectively. Leptin expression was inversely associated with the number of sperm in the left epididymis, thickness of the seminiferous epithelium and the diameter of seminiferous tubules. The expression of leptin receptors in the hypothalamus of G2 and G4 was significantly increased compared with that in G1 and G3, respectively. The mRNA levels of KiSS-1, GPR54, GnRH, LH and FSH in G2 and G4 were significantly increased compared with that in G1 and G3, respectively. Serum testosterone levels in G2 and G4 rats were significantly lower than those in G1 and G3 rats, respectively. There was no significant difference between the serum levels of FSH, LH and leptin. These results suggest that leptin and its receptor may serve significant roles in the pathogenesis of varicocele-induced testicular dysfunction.
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Affiliation(s)
- Jie Zhang
- Department of Urology, Shanghai Pudong Hospital, Fudan University, Shanghai 201399, P.R. China
| | - Peng-Peng Jin
- Center for Medical Research, Shanghai Pudong Hospital, Fudan University, Shanghai 201399, P.R. China
| | - Min Gong
- Department of Urology, Shanghai Pudong Hospital, Fudan University, Shanghai 201399, P.R. China
| | - Qing-Tong Yi
- Department of Urology, Shanghai Pudong Hospital, Fudan University, Shanghai 201399, P.R. China
| | - Ru-Jian Zhu
- Department of Urology, Shanghai Pudong Hospital, Fudan University, Shanghai 201399, P.R. China
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18
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Filipino Women’s Preferences for Male Voice Pitch: Intra-Individual, Life History, and Hormonal Predictors. ADAPTIVE HUMAN BEHAVIOR AND PHYSIOLOGY 2018. [DOI: 10.1007/s40750-018-0087-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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19
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Motta-Mena NV, Puts DA. Endocrinology of human female sexuality, mating, and reproductive behavior. Horm Behav 2017; 91:19-35. [PMID: 27866819 DOI: 10.1016/j.yhbeh.2016.11.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 11/02/2016] [Accepted: 11/12/2016] [Indexed: 10/20/2022]
Abstract
Hormones orchestrate and coordinate human female sexual development, sexuality, and reproduction in relation to three types of phenotypic changes: life history transitions such as puberty and childbirth, responses to contextual factors such as caloric intake and stress, and cyclical patterns such as the ovulatory cycle. Here, we review the endocrinology underlying women's reproductive phenotypes, including sexual orientation and gender identity, mate preferences, competition for mates, sex drive, and maternal behavior. We highlight distinctive aspects of women's sexuality such as the possession of sexual ornaments, relatively cryptic fertile windows, extended sexual behavior across the ovulatory cycle, and a period of midlife reproductive senescence-and we focus on how hormonal mechanisms were shaped by selection to produce adaptive outcomes. We conclude with suggestions for future research to elucidate how hormonal mechanisms subserve women's reproductive phenotypes.
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Affiliation(s)
- Natalie V Motta-Mena
- Department of Psychology, Pennsylvania State University, University Park, PA 16802, United States
| | - David A Puts
- Department of Anthropology, Center for Brain, Behavior, and Cognition, Center for Human Evolution and Diversity, Pennsylvania State University, University Park, PA 16802¸ United States.
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20
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Abstract
The hypothalamic control of prolactin secretion is different from other anterior pituitary hormones, in that it is predominantly inhibitory, by means of dopamine from the tuberoinfundibular dopamine neurons. In addition, prolactin does not have an endocrine target tissue, and therefore lacks the classical feedback pathway to regulate its secretion. Instead, it is regulated by short loop feedback, whereby prolactin itself acts in the brain to stimulate production of dopamine and thereby inhibit its own secretion. Finally, despite its relatively simple name, prolactin has a broad range of functions in the body, in addition to its defining role in promoting lactation. As such, the hypothalamo-prolactin axis has many characteristics that are quite distinct from other hypothalamo-pituitary systems. This review will provide a brief overview of our current understanding of the neuroendocrine control of prolactin secretion, in particular focusing on the plasticity evident in this system, which keeps prolactin secretion at low levels most of the time, but enables extended periods of hyperprolactinemia when necessary for lactation. Key prolactin functions beyond milk production will be discussed, particularly focusing on the role of prolactin in inducing adaptive responses in multiple different systems to facilitate lactation, and the consequences if prolactin action is impaired. A feature of this pleiotropic activity is that functions that may be adaptive in the lactating state might be maladaptive if prolactin levels are elevated inappropriately. Overall, my goal is to give a flavour of both the history and current state of the field of prolactin neuroendocrinology, and identify some exciting new areas of research development.
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Affiliation(s)
- David R Grattan
- Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago, PO Box 913, Dunedin 9054, New ZealandMaurice Wilkins Centre for Molecular BiodiscoveryAuckland, New Zealand Centre for Neuroendocrinology and Department of AnatomyUniversity of Otago, PO Box 913, Dunedin 9054, New ZealandMaurice Wilkins Centre for Molecular BiodiscoveryAuckland, New Zealand
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21
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Wahab F, Shahab M, Behr R. The involvement of gonadotropin inhibitory hormone and kisspeptin in the metabolic regulation of reproduction. J Endocrinol 2015; 225:R49-66. [PMID: 25957191 DOI: 10.1530/joe-14-0688] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recently, kisspeptin (KP) and gonadotropin inhibitory hormone (GnIH), two counteracting neuropeptides, have been acknowledged as significant regulators of reproductive function. KP stimulates reproduction while GnIH inhibits it. These two neuropeptides seem to be pivotal for the modulation of reproductive activity in response to internal and external cues. It is well-documented that the current metabolic status of the body is closely linked to its reproductive output. However, how reproductive function is regulated by the body's energy status is less clear. Recent studies have suggested an active participation of hypothalamic KP and GnIH in the modulation of reproductive function according to available metabolic cues. Expression of KISS1, the KP encoding gene, is decreased while expression of RFRP (NPVF), the gene encoding GnIH, is increased in metabolic deficiency conditions. The lower levels of KP, as suggested by a decrease in KISS1 gene mRNA expression, during metabolic deficiency can be corrected by administration of exogenous KP, which leads to an increase in reproductive hormone levels. Likewise, administration of RF9, a GnIH receptor antagonist, can reverse the inhibitory effect of fasting on testosterone in monkeys. Together, it is likely that the integrated function of both these hypothalamic neuropeptides works as a reproductive output regulator in response to a change in metabolic status. In this review, we have summarized literature from nonprimate and primate studies that demonstrate the involvement of KP and GnIH in the metabolic regulation of reproduction.
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Affiliation(s)
- F Wahab
- Stem Cell Biology Unit Leibniz Institute for Primate Research, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany Laboratory of Reproductive Neuroendocrinology Department of Animal Sciences, Faculty of Biological Sciences, Quiad-i-Azam University, Islamabad, Pakistan
| | - M Shahab
- Stem Cell Biology Unit Leibniz Institute for Primate Research, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany Laboratory of Reproductive Neuroendocrinology Department of Animal Sciences, Faculty of Biological Sciences, Quiad-i-Azam University, Islamabad, Pakistan
| | - R Behr
- Stem Cell Biology Unit Leibniz Institute for Primate Research, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany Laboratory of Reproductive Neuroendocrinology Department of Animal Sciences, Faculty of Biological Sciences, Quiad-i-Azam University, Islamabad, Pakistan
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22
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Skrapits K, Borsay BÁ, Herczeg L, Ciofi P, Liposits Z, Hrabovszky E. Neuropeptide co-expression in hypothalamic kisspeptin neurons of laboratory animals and the human. Front Neurosci 2015; 9:29. [PMID: 25713511 PMCID: PMC4322635 DOI: 10.3389/fnins.2015.00029] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 01/21/2015] [Indexed: 11/13/2022] Open
Abstract
Hypothalamic peptidergic neurons using kisspeptin (KP) and its co-transmitters for communication are critically involved in the regulation of mammalian reproduction and puberty. This article provides an overview of neuropeptides present in KP neurons, with a focus on the human species. Immunohistochemical studies reveal that large subsets of human KP neurons synthesize neurokinin B, as also shown in laboratory animals. In contrast, dynorphin described in KP neurons of rodents and sheep is found rarely in KP cells of human males and postmenopausal females. Similarly, galanin is detectable in mouse, but not human, KP cells, whereas substance P, cocaine- and amphetamine-regulated transcript and proenkephalin-derived opioids are expressed in varying subsets of KP neurons in humans, but not reported in ARC of other species. Human KP neurons do not contain neurotensin, cholecystokinin, proopiomelanocortin-derivatives, agouti-related protein, neuropeptide Y, somatostatin or tyrosine hydroxylase (dopamine). These data identify the possible co-transmitters of human KP cells. Neurochemical properties distinct from those of laboratory species indicate that humans use considerably different neurotransmitter mechanisms to regulate fertility.
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Affiliation(s)
- Katalin Skrapits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary
| | - Beáta Á Borsay
- Department of Forensic Medicine, Clinical Center, University of Debrecen Debrecen, Hungary
| | - László Herczeg
- Department of Forensic Medicine, Clinical Center, University of Debrecen Debrecen, Hungary
| | - Philippe Ciofi
- Neurocentre Magendie, Institut National de la Santé et de la Recherche Médicale U862 Bordeaux, France
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary ; Department of Neuroscience, Faculty of Information Technology and Bionics, Pázmány Péter Catholic University Budapest, Hungary
| | - Erik Hrabovszky
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Budapest, Hungary
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23
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Brown RSE, Herbison AE, Grattan DR. Prolactin regulation of kisspeptin neurones in the mouse brain and its role in the lactation-induced suppression of kisspeptin expression. J Neuroendocrinol 2014; 26:898-908. [PMID: 25207795 DOI: 10.1111/jne.12223] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 09/04/2014] [Accepted: 09/05/2014] [Indexed: 11/26/2022]
Abstract
Hyperprolactinaemia is a major cause of infertility in both males and females, although the mechanism by which prolactin inhibits the reproductive axis is not clear. The aim of the present study was to test the hypothesis that elevated prolactin causes suppression of kisspeptin expression in the hypothalamus, resulting in reduced release of gonadotrophin-releasing hormone (GnRH) and consequent infertility. In oestrogen-treated ovariectomised mice, chronic prolactin-treatment prevented the rise in luteinising hormone (LH) seen in vehicle-treated mice. Kiss1 mRNA was significantly suppressed in both the rostral periventricular region of the third ventricle (RP3V) and arcuate nucleus after prolactin treatment. Exogenous prolactin treatment induced phosphorylated signal transducer and activator of transcription 5 (pSTAT5) in kisspeptin neurones, and suppression of endogenous prolactin using bromocriptine reduced levels of pSTAT5 in kisspeptin neurones, suggesting that prolactin acts directly on kisspeptin neurones. By contrast, fewer than 1% of GnRH neurones expressed pSTAT5 in either dioestrous or lactating mice. As reported previously, there was significant suppression of kisspeptin mRNA and protein in the RP3V on day 7 of lactation, although not in the arcuate nucleus. Bromocriptine treatment significantly increased Kiss1 mRNA expression in the RP3V, although not to dioestrous levels. Unilateral thelectomy, aiming to eliminate sensory inputs from nipples on one side of the body, failed to alter the reduction in the number of kisspeptin neurones observed in the RP3V. These data demonstrate that chronic prolactin administration suppressed serum LH, and reduced Kiss1 mRNA levels in both the RP3V and arcuate nucleus, consistent with the hypothesis that prolactin-induced suppression of kisspeptin secretion might mediate the inhibitory effects of prolactin on GnRH secretion. During lactation, however, the suppression of Kiss1 mRNA in the RP3V was only partially reversed by the administration of bromocriptine to block elevated levels of prolactin, suggesting that, although elevated prolactin contributes to lactational anovulation, additional non-neural factors must also contribute to the lactation-induced suppression of kisspeptin neurones.
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Affiliation(s)
- R S E Brown
- Department of Anatomy, Centre for Neuroendocrinology, School of Medical Sciences, University of Otago, Dunedin, New Zealand
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Shukla KK, Chambial S, Dwivedi S, Misra S, Sharma P. Recent scenario of obesity and male fertility. Andrology 2014; 2:809-18. [DOI: 10.1111/andr.270] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 07/28/2014] [Accepted: 08/06/2014] [Indexed: 12/26/2022]
Affiliation(s)
- K. K. Shukla
- Department of Biochemistry; All India Institute of Medical Sciences; Jodhpur Rajasthan India
| | - S. Chambial
- Department of Biochemistry; All India Institute of Medical Sciences; Jodhpur Rajasthan India
| | - S. Dwivedi
- Department of Biochemistry; All India Institute of Medical Sciences; Jodhpur Rajasthan India
| | - S. Misra
- Department of Surgical Oncology; All India Institute of Medical Sciences; Jodhpur Rajasthan India
| | - P. Sharma
- Department of Biochemistry; All India Institute of Medical Sciences; Jodhpur Rajasthan India
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Rønnekleiv OK, Fang Y, Zhang C, Nestor CC, Mao P, Kelly MJ. Research resource: Gene profiling of G protein-coupled receptors in the arcuate nucleus of the female. Mol Endocrinol 2014; 28:1362-80. [PMID: 24933249 PMCID: PMC4116592 DOI: 10.1210/me.2014-1103] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The hypothalamic arcuate nucleus controls many critical homeostatic functions including energy homeostasis, reproduction, and motivated behavior. Although G protein-coupled receptors (GPCRs) are involved in the regulation of these functions, relatively few of the GPCRs have been identified specifically within the arcuate nucleus. Here, using TaqMan low-density arrays we quantified the mRNA expression of nonolfactory GPCRs in mouse arcuate nucleus. An unprecedented number of GPCRs (total of 292) were found to be expressed, of which 183 were known and 109 were orphan GPCRs. The known GPCR genes expressed were classified into several functional clusters including hormone/neurotransmitter, growth factor, angiogenesis and vasoactivity, inflammation and immune system, and lipid messenger receptors. The plethora of orphan genes expressed in the arcuate nucleus were classified into 5 structure-related classes including class A (rhodopsin-like), class B (adhesion), class C (other GPCRs), nonsignaling 7-transmembrane chemokine-binding proteins, and other 7-transmembrane proteins. Therefore, for the first time, we provide a quantitative estimate of the numerous GPCRs expressed in the hypothalamic arcuate nucleus. Finally, as proof of principle, we documented the expression and function of one of these receptor genes, the glucagon-like peptide 1 receptor (Glp1r), which was highly expressed in the arcuate nucleus. Single-cell RT-PCR revealed that Glp1r mRNA was localized in proopiomelanocortin neurons, and using whole-cell recording we found that the glucagon-like peptide 1-selective agonist exendin-4 robustly excited proopiomelanocortin neurons. Thus, the quantitative GPCR data emphasize the complexity of the hypothalamic arcuate nucleus and furthermore provide a valuable resource for future neuroendocrine/endocrine-related experiments.
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Affiliation(s)
- Oline K Rønnekleiv
- Department of Physiology and Pharmacology (O.K.R., Y.F., C.Z., C.CN., P.M., M.J.K.), Oregon Health and Science University, Portland, Oregon 97239; and Division of Neuroscience (O.K.R., P.M., M.J.K.), Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon 97006
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Sliwowska JH, Fergani C, Gawałek M, Skowronska B, Fichna P, Lehman MN. Insulin: its role in the central control of reproduction. Physiol Behav 2014; 133:197-206. [PMID: 24874777 DOI: 10.1016/j.physbeh.2014.05.021] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 05/13/2014] [Accepted: 05/19/2014] [Indexed: 12/11/2022]
Abstract
Insulin has long been recognized as a key regulator of energy homeostasis via its actions at the level of the brain, but in addition, plays a role in regulating neural control of reproduction. In this review, we consider and compare evidence from animal models demonstrating a role for insulin for physiological control of reproduction by effects on GnRH/LH secretion. We also review the role that insulin plays in prenatal programming of adult reproduction, and consider specific candidate neurons in the adult hypothalamus by which insulin may act to regulate reproductive function. Finally, we review clinical evidence of the role that insulin may play in adult human fertility and reproductive disorders. Overall, while insulin appears to have a significant impact on reproductive neuroendocrine function, there are many unanswered questions regarding its precise sites and mechanisms of action, and their impact on developing and adult reproductive neuroendocrine function.
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Affiliation(s)
- Joanna H Sliwowska
- Laboratory of Neurobiology, Institute of Zoology, Poznan University of Life Sciences, ul. Wojska Polskiego 71 C, 60-625 Poznan, Poland.
| | - Chrysanthi Fergani
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, MS 39232, USA.
| | - Monika Gawałek
- Laboratory of Neurobiology, Institute of Zoology, Poznan University of Life Sciences, ul. Wojska Polskiego 71 C, 60-625 Poznan, Poland.
| | - Bogda Skowronska
- Department of Pediatric Diabetes and Obesity, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznan, Poland.
| | - Piotr Fichna
- Department of Pediatric Diabetes and Obesity, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznan, Poland.
| | - Michael N Lehman
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, MS 39232, USA.
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Verma S, Kirigiti M, Millar RP, Grove KL, Smith MS. Endogenous kisspeptin tone is a critical excitatory component of spontaneous GnRH activity and the GnRH response to NPY and CART. Neuroendocrinology 2014; 99:190-203. [PMID: 25011649 PMCID: PMC4201869 DOI: 10.1159/000365419] [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: 09/18/2013] [Accepted: 06/22/2014] [Indexed: 12/17/2022]
Abstract
BACKGROUND/AIMS Kisspeptin is the major excitatory regulator of gonadotropin-releasing hormone (GnRH) neurons and is responsible for basal GnRH/LH release and the GnRH/LH surge. Although it is widely assumed, based on mutations in kisspeptin and Kiss1R, that kisspeptin acts to sustain basal GnRH neuronal activity, there have been no studies to investigate whether endogenous basal kisspeptin tone plays a direct role in basal spontaneous GnRH neuronal excitability. It is also of interest to examine possible interactions between endogenous kisspeptin tone and other neuropeptides that have direct effects on GnRH neurons, such as neuropeptide Y (NPY) or cocaine- and amphetamine-regulated transcript (CART), since the activity of all these neuropeptides changes during states of negative energy balance. METHODS Loose cell-attached and whole-cell current patch-clamp recordings were made from GnRH-GFP neurons in hypothalamic slices from female and male rats. RESULTS Kisspeptin activated GnRH neurons in a concentration-dependent manner with an EC50 of 3.32 ± 0.02 nM. Surprisingly, a kisspeptin antagonist, Peptide 347, suppressed spontaneous activity in GnRH neurons, demonstrating the essential nature of the endogenous kisspeptin tone. Furthermore, inhibition of endogenous kisspeptin tone blocked the direct activation of GnRH cells that occurs in response to antagonism of NPY Y5 receptor or by CART. CONCLUSIONS Our electrophysiology studies suggest that basal endogenous kisspeptin tone is not only essential for spontaneous GnRH neuronal firing, but it is also required for the net excitatory effects of other neuropeptides, such as CART or NPY antagonism, on GnRH neurons. Therefore, endogenous kisspeptin tone could serve as the linchpin in GnRH activation or inhibition.
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Affiliation(s)
- Saurabh Verma
- Division of Diabetes, Obesity and Metabolism, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006
| | - Melissa Kirigiti
- Division of Diabetes, Obesity and Metabolism, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006
| | - Robert P. Millar
- MRC Receptor Biology & Reproductive Health, University of Pretoria, Pretoria, South Africa
| | - Kevin L. Grove
- Division of Diabetes, Obesity and Metabolism, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006
| | - M. Susan Smith
- Division of Diabetes, Obesity and Metabolism, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon 97006
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Liu X, Brown RSE, Herbison AE, Grattan DR. Lactational anovulation in mice results from a selective loss of kisspeptin input to GnRH neurons. Endocrinology 2014; 155:193-203. [PMID: 24169550 DOI: 10.1210/en.2013-1621] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In mammals, lactation is associated with a period of infertility characterized by the loss of pulsatile secretion of GnRH and cessation of ovulatory cycles. Despite the importance of lactational infertility in determining overall fecundity of a species, the mechanisms by which the suckling stimulus suppresses GnRH secretion remain unclear. Because kisspeptin neurons are critical for fertility, the aim of this study was to test the hypothesis that reduced kisspeptin expression might mediate the lactation-induced suppression of fertility, using mouse models. In the rostral periventricular area of the third ventricle (RP3V), a progressive decrease in RP3V Kiss1 mRNA levels was observed during pregnancy culminating in a 10-fold reduction during lactation compared with diestrous controls. This was associated with approximately 60% reduction in the numbers of kisspeptin-immunoreactive neurons in the RP3V detected during lactation. Similarly, in the arcuate nucleus there was also a significant decrease in Kiss1 mRNA levels during late pregnancy and midlactation, and a notable decrease in kisspeptin fiber density during lactation. The functional characteristics of the RP3V kisspeptin input to GnRH neurons were assessed using electrophysiological approaches in an acute brain slice preparation. Although endogenous RP3V kisspeptin neurons were found to activate GnRH neurons in diestrous mice, this was never observed during lactation. This did not result from an absence of kisspeptin receptors because GnRH neurons responded normally to 100 nM exogenous kisspeptin during lactation. The kisspeptin deficit in lactating mice was selective, because GnRH neurons responded normally to RP3V gamma aminobutryic acid inputs during lactation. These data demonstrate that a selective loss of RP3V kisspeptin inputs to GnRH neurons during lactation is the likely mechanism causing lactational anovulation in the mouse.
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Affiliation(s)
- X Liu
- Centre for Neuroendocrinology and Departments of Physiology (X.L., A.E.H.) and Anatomy (R.S.E.B., D.R.G.), School of Medical Sciences, University of Otago, Dunedin, 9054 New Zealand
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Sheffer-Babila S, Sun Y, Israel DD, Liu SM, Neal-Perry G, Chua SC. Agouti-related peptide plays a critical role in leptin's effects on female puberty and reproduction. Am J Physiol Endocrinol Metab 2013; 305:E1512-20. [PMID: 24169048 PMCID: PMC3882375 DOI: 10.1152/ajpendo.00241.2013] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Deficient leptin signaling causes infertility via reduced activity of GnRH neurons, causing a hypogonadal state in both rodents and humans. Because GnRH neurons do not express leptin receptors, leptin's effect on GnRH neurons must be indirect. Neurons within the hypothalamic arcuate nucleus that coexpress AGRP and NPY are considered to be important intermediate neurons involved in leptin regulation of GnRH neurons. Previously, we reported that the absence of AGRP and haploinsufficiency of MC4R in leptin receptor mutant (Lepr(db/db)) females result in restoration of fertility and lactation despite the persistence of obesity and insulin resistance. The overarching hypothesis in the present study is that the absence or reduction of leptin's inhibition of AGRP/NPY neurons leads to suppression of GnRH release in cases of leptin signaling deficiency. Since TAC2 (NKB)-TAC3R signaling plays a role in puberty maturation and is modulated by metabolic status, the other aim of this study is to test whether TAC2/NKB neurons in ARC regulated by melanocortinergic signals herein affect leptin's action on puberty and reproduction. Our data showed that AGRP deficiency in Lepr(db/db) females restores normal timing of vaginal opening and estrous cycling, although uterine weight gain and mammary gland development are morphologically delayed. Nonetheless, Agrp(-/-) Lepr(db/db) females are fertile and sustain adequate nutrition of pups with lactation to weaning age. AGRP deficiency results in advanced vaginal opening in wild-type female mice. The postpubertal increase in hypothalamic TAC2 mRNA was not observed in Lepr(db/db) females, whereas AGRP deficiency restored it in Lepr(db/db) females. Additionally, MC4R activation with MTII induced FOS expression in TAC2 neurons, supporting the concept of melanocortinergic regulation of TAC2 neurons. These studies suggest that AGRP imposes an inhibitory effect on puberty and that TAC2 neurons may transmit melanocortinergic inhibition of GnRH neurons.
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Affiliation(s)
- Sharone Sheffer-Babila
- Division of Endocrinology, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York
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30
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Lee SJ, Kirigiti M, Lindsley SR, Loche A, Madden CJ, Morrison SF, Smith MS, Grove KL. Efferent projections of neuropeptide Y-expressing neurons of the dorsomedial hypothalamus in chronic hyperphagic models. J Comp Neurol 2013; 521:1891-914. [PMID: 23172177 DOI: 10.1002/cne.23265] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 08/15/2012] [Accepted: 11/06/2012] [Indexed: 12/31/2022]
Abstract
The dorsomedial hypothalamus (DMH) has long been implicated in feeding behavior and thermogenesis. The DMH contains orexigenic neuropeptide Y (NPY) neurons, but the role of these neurons in the control of energy homeostasis is not well understood. NPY expression in the DMH is low under normal conditions in adult rodents but is significantly increased during chronic hyperphagic conditions such as lactation and diet-induced obesity (DIO). To understand better the role of DMH-NPY neurons, we characterized the efferent projections of DMH-NPY neurons using the anterograde tracer biotinylated dextran amine (BDA) in lactating rats and DIO mice. In both models, BDA- and NPY-colabeled fibers were limited mainly to the hypothalamus, including the paraventricular nucleus of the hypothalamus (PVH), lateral hypothalamus/perifornical area (LH/PFA), and anteroventral periventricular nucleus (AVPV). Specifically in lactating rats, BDA-and NPY-colabeled axonal swellings were in close apposition to cocaine- and amphetamine-regulated transcript (CART)-expressing neurons in the PVH and AVPV. Although the DMH neurons project to the rostral raphe pallidus (rRPa), these projections did not contain NPY immunoreactivity in either the lactating rat or the DIO mouse. Instead, the majority of BDA-labeled fibers in the rRPa were orexin positive. Furthermore, DMH-NPY projections were not observed within the nucleus of the solitary tract (NTS), another brainstem site critical for the regulation of sympathetic outflow. The present data suggest that NPY expression in the DMH during chronic hyperphagic conditions plays important roles in feeding behavior and thermogenesis by modulating neuronal functions within the hypothalamus, but not in the brainstem.
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Affiliation(s)
- Shin J Lee
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon 97006, USA
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31
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True C, Verma S, Grove KL, Smith MS. Cocaine- and amphetamine-regulated transcript is a potent stimulator of GnRH and kisspeptin cells and may contribute to negative energy balance-induced reproductive inhibition in females. Endocrinology 2013; 154:2821-32. [PMID: 23736294 PMCID: PMC3713223 DOI: 10.1210/en.2013-1156] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cocaine- and amphetamine-regulated transcript (CART) is a hypothalamic neuropeptide implicated in both metabolic and reproductive regulation, raising the possibility that CART plays a role in reproductive inhibition during negative metabolic conditions. The current study characterized CART's regulatory influence on GnRH and kisspeptin (Kiss1) cells and determined the sensitivity of different CART populations to negative energy balance. CART fibers made close appositions to 60% of GnRH cells, with the majority of the fibers (>80%) originating from the arcuate nucleus (ARH) CART/pro-opiomelanocortin population. Electrophysiological recordings in GnRH-green fluorescent protein rats demonstrated that CART postsynaptically depolarizes GnRH cells. CART fibers from the ARH were also observed in close contact with Kiss1 cells in the ARH and anteroventral periventricular nucleus (AVPV). Recordings in Kiss1-GFP mice demonstrated CART also postsynaptically depolarizes ARH Kiss1 cells, suggesting CART may act directly and indirectly, via Kiss1 populations, to stimulate GnRH neurons. CART protein and mRNA levels were analyzed in 2 models of negative energy balance: caloric restriction (CR) and lactation. Both CART mRNA levels and the number of CART-immunoreactive cells were suppressed in the ARH during CR but not during lactation. AVPV CART mRNA was suppressed during CR, but not during lactation when there was a dramatic increase in CART-immunoreactive cells. These data suggest differing regulatory signals of CART between the models. In conclusion, both morphological and electrophysiological methods identify CART as a novel and potent stimulator of Kiss1 and GnRH neurons and suppression of CART expression during negative metabolic conditions could contribute to inhibition of the reproductive axis.
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Affiliation(s)
- Cadence True
- Divisions of Diabetes, Obesity, & Metabolism, and Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
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32
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Sonigo C, Binart N. Overview of the impact of kisspeptin on reproductive function. ANNALES D'ENDOCRINOLOGIE 2012; 73:448-58. [DOI: 10.1016/j.ando.2012.07.680] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 07/23/2012] [Indexed: 11/16/2022]
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Ghasemi R, Haeri A, Dargahi L, Mohamed Z, Ahmadiani A. Insulin in the brain: sources, localization and functions. Mol Neurobiol 2012; 47:145-71. [PMID: 22956272 DOI: 10.1007/s12035-012-8339-9] [Citation(s) in RCA: 203] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 08/20/2012] [Indexed: 02/07/2023]
Abstract
Historically, insulin is best known for its role in peripheral glucose homeostasis, and insulin signaling in the brain has received less attention. Insulin-independent brain glucose uptake has been the main reason for considering the brain as an insulin-insensitive organ. However, recent findings showing a high concentration of insulin in brain extracts, and expression of insulin receptors (IRs) in central nervous system tissues have gathered considerable attention over the sources, localization, and functions of insulin in the brain. This review summarizes the current status of knowledge of the peripheral and central sources of insulin in the brain, site-specific expression of IRs, and also neurophysiological functions of insulin including the regulation of food intake, weight control, reproduction, and cognition and memory formation. This review also considers the neuromodulatory and neurotrophic effects of insulin, resulting in proliferation, differentiation, and neurite outgrowth, introducing insulin as an attractive tool for neuroprotection against apoptosis, oxidative stress, beta amyloid toxicity, and brain ischemia.
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Affiliation(s)
- Rasoul Ghasemi
- Department of Physiology, Faculty of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Pinilla L, Aguilar E, Dieguez C, Millar RP, Tena-Sempere M. Kisspeptins and Reproduction: Physiological Roles and Regulatory Mechanisms. Physiol Rev 2012; 92:1235-316. [DOI: 10.1152/physrev.00037.2010] [Citation(s) in RCA: 529] [Impact Index Per Article: 44.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Procreation is essential for survival of species. Not surprisingly, complex neuronal networks have evolved to mediate the diverse internal and external environmental inputs that regulate reproduction in vertebrates. Ultimately, these regulatory factors impinge, directly or indirectly, on a final common pathway, the neurons producing the gonadotropin-releasing hormone (GnRH), which stimulates pituitary gonadotropin secretion and thereby gonadal function. Compelling evidence, accumulated in the last few years, has revealed that kisspeptins, a family of neuropeptides encoded by the Kiss1 gene and produced mainly by neuronal clusters at discrete hypothalamic nuclei, are pivotal upstream regulators of GnRH neurons. As such, kisspeptins have emerged as important gatekeepers of key aspects of reproductive maturation and function, from sexual differentiation of the brain and puberty onset to adult regulation of gonadotropin secretion and the metabolic control of fertility. This review aims to provide a comprehensive account of the state-of-the-art in the field of kisspeptin physiology by covering in-depth the consensus knowledge on the major molecular features, biological effects, and mechanisms of action of kisspeptins in mammals and, to a lesser extent, in nonmammalian vertebrates. This review will also address unsolved and contentious issues to set the scene for future research challenges in the area. By doing so, we aim to endow the reader with a critical and updated view of the physiological roles and potential translational relevance of kisspeptins in the integral control of reproductive function.
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Affiliation(s)
- Leonor Pinilla
- 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 Investigaciones Biomédicas, Córdoba, Spain; Department of Physiology, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; and Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Enrique Aguilar
- 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 Investigaciones Biomédicas, Córdoba, Spain; Department of Physiology, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; and Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Carlos Dieguez
- 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 Investigaciones Biomédicas, Córdoba, Spain; Department of Physiology, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; and Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Robert P. Millar
- 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 Investigaciones Biomédicas, Córdoba, Spain; Department of Physiology, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; and Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Manuel Tena-Sempere
- 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 Investigaciones Biomédicas, Córdoba, Spain; Department of Physiology, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; and Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
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Morrison SF, Madden CJ, Tupone D. An orexinergic projection from perifornical hypothalamus to raphe pallidus increases rat brown adipose tissue thermogenesis. Adipocyte 2012; 1:116-120. [PMID: 23538704 PMCID: PMC3607627 DOI: 10.4161/adip.19736] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Non-shivering thermogenesis in brown adipose tissue (BAT) plays an important role in thermoregulatory cold-defense and, through its metabolic consumption of energy reserves to produce heat, can affect the long-term regulation of adiposity. An orexinergic pathway from the perifornical lateral hypothalamus (PeF/LH) to the rostral raphe pallidus (rRPa) has been demonstrated to increase the gain of the excitatory drives to medullary sympathetic premotor neurons controlling BAT sympathetic outflow and BAT thermogenesis. With this background, we consider neural mechanisms that could underlie orexin’s modulation of the excitability of BAT sympathetic premotor neurons in rRPa and the potential role of altered BAT thermogenesis in pathological conditions associated with the absence of the central orexin system. Overall, these new data enhance our understanding of the role of central orexin in regulating body temperature and energy homeostasis and provide further insight into the neurochemical regulation of BAT thermogenesis and metabolism.
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Król E, Martin SAM, Huhtaniemi IT, Douglas A, Speakman JR. Negative correlation between milk production and brown adipose tissue gene expression in lactating mice. J Exp Biol 2011; 214:4160-70. [DOI: 10.1242/jeb.061382] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
SUMMARY
It has been proposed that the performance of lactating animals is limited by the capacity of the female to dissipate body heat – the heat dissipation limit (HDL) theory. This theory predicts that milk production might be constrained not by intrinsic properties of the mammary glands but rather by competitive heat production such as thermogenesis in brown adipose tissue (BAT). To test this prediction, we measured the expression of genes linked to thermogenesis in BAT of lactating laboratory mice. The applicability of BAT gene expression to reflect thermogenic activity of BAT was confirmed by a positive relationship between expression levels of several BAT genes (summarised by the first principal component following principal component analysis) and daily energy expenditure in virgin mice. Milk production at peak lactation was strongly and negatively associated with the expression of thermogenic genes in BAT. Downregulation of these genes during lactation was correlated with low levels of circulating leptin and high levels of circulating prolactin. Our results are consistent with the HDL theory. However, we cannot discount the converse interpretation that milk production may reduce BAT activity. If the reduction in BAT activity does facilitate increased milk production, then reducing the heat generated by competitive processes may be a more productive route to increase lactational performance than attempts to improve mammary gland performance in isolation from the other body systems.
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Affiliation(s)
- Elzbieta Król
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK
- Mammal Research Institute PAS, 17-230 Białowieza, Poland
| | - Samuel A. M. Martin
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK
| | - Ilpo T. Huhtaniemi
- Institute of Reproductive and Developmental Biology, Imperial College London, London W12 0NN, UK
- Department of Physiology, University of Turku, FIN-20520 Turku, Finland
| | - Alex Douglas
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK
| | - John R. Speakman
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK
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Tupone D, Madden CJ, Cano G, Morrison SF. An orexinergic projection from perifornical hypothalamus to raphe pallidus increases rat brown adipose tissue thermogenesis. J Neurosci 2011; 31:15944-55. [PMID: 22049437 PMCID: PMC3224674 DOI: 10.1523/jneurosci.3909-11.2011] [Citation(s) in RCA: 172] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 09/07/2011] [Accepted: 09/20/2011] [Indexed: 01/12/2023] Open
Abstract
Orexin (hypocretin) neurons, located exclusively in the PeF-LH, which includes the perifornical area (PeF), the lateral hypothalamus (LH), and lateral portions of the medial hypothalamus, have widespread projections and influence many physiological functions, including the autonomic regulation of body temperature and energy metabolism. Narcolepsy is characterized by the loss of orexin neurons and by disrupted sleep, but also by dysregulation of body temperature and by a strong tendency for obesity. Heat production (thermogenesis) in brown adipose tissue (BAT) contributes to the maintenance of body temperature and, through energy consumption, to body weight regulation. We identified a neural substrate for the influence of orexin neurons on BAT thermogenesis in rat. Nanoinjection of orexin-A (12 pmol) into the rostral raphe pallidus (rRPa), the site of BAT sympathetic premotor neurons, produced large, sustained increases in BAT sympathetic outflow and in BAT thermogenesis. Activation of neurons in the PeF-LH also enhanced BAT thermogenesis over a long time course. Combining viral retrograde tracing from BAT, or cholera toxin subunit b tracing from rRPa, with orexin immunohistochemistry revealed synaptic connections to BAT from orexin neurons in PeF-LH and from rRPa neurons with closely apposed, varicose orexin fibers, as well as a direct, orexinergic projection from PeF-LH to rRPa. These results indicate a potent modulation of BAT thermogenesis by orexin released from the terminals of orexin neurons in PeF-LH directly into the rRPa and provide a potential mechanism contributing to the disrupted regulation of body temperature and energy metabolism in the absence of orexin.
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Affiliation(s)
- Domenico Tupone
- Department of Neurological Surgery, Oregon Health & Science University, Portland, Oregon 97239-3098, USA.
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Dobolyi A. Novel potential regulators of maternal adaptations during lactation: tuberoinfundibular peptide 39 and amylin. J Neuroendocrinol 2011; 23:1002-8. [PMID: 21418340 DOI: 10.1111/j.1365-2826.2011.02127.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Maternal adaptations during lactation include milk synthesis and ejection, the appearance of maternal behaviours, reduced stress response, suppression of the ovarian cycle, and increased food and fluid intake. Several recently identified neuropeptides may participate in these adaptations, and we focus on two of them in the present study: tuberoinfundibular peptide of 39 residues (TIP39) and amylin. TIP39 is the ligand of the parathyroid hormone 2 receptor (PTH2 receptor) is induced in the posterior intralaminar complex of the thalamus (PIL) during lactation. TIP39 neurones in the PIL are activated in mother rats in response to pup exposure and project to preoptic, periventricular, paraventricular, arcuate and dorsomedial regions of the hypothalamus. Furthermore, an antagonist of the PTH2 receptor reduced suckling induced prolactin release. On the basis of their projections, TIP39 neurones might interact with additional neurones involved in maternal adaptations, including kisspeptin neurones participating in the control of gonadotrophin-releasing hormone function. TIP39 fibres might also interact with amylin, a peptide that we recently identified to appear in the preoptic area of rat dams. On the basis of its distribution, preoptic amylin could play a role in the control of maternal behaviours. We hypothesise that TIP39 neurones mediate the effects of suckling on different hypothalamic systems to affect maternal adaptations.
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Affiliation(s)
- A Dobolyi
- Department of Anatomy, Histology and Embryology, Neuromorphological and Neuroendocrine Research Laboratory, Semmelweis University and Hungarian Academy of Sciences, Budapest, Hungary.
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True C, Grove KL, Smith MS. Beyond Leptin: Emerging Candidates for the Integration of Metabolic and Reproductive Function during Negative Energy Balance. Front Endocrinol (Lausanne) 2011; 2:53. [PMID: 22645510 PMCID: PMC3355832 DOI: 10.3389/fendo.2011.00053] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 09/29/2011] [Indexed: 12/19/2022] Open
Abstract
Reproductive status is tightly coupled to metabolic state in females, and ovarian cycling in mammals is halted when energy output exceeds energy input, a metabolic condition known as negative energy balance. This inhibition of reproductive function during negative energy balance occurs due to suppression of gonadotropin-releasing hormone (GnRH) release in the hypothalamus. The GnRH secretagogue kisspeptin is also inhibited during negative energy balance, indicating that inhibition of reproductive neuroendocrine circuits may occur upstream of GnRH itself. Understanding the metabolic signals responsible for the inhibition of reproductive pathways has been a compelling research focus for many years. A predominant theory in the field is that the status of energy balance is conveyed to reproductive neuroendocrine circuits via the adipocyte hormone leptin. Leptin is stimulatory for GnRH release and lower levels of leptin during negative energy balance are believed to result in decreased stimulatory drive for GnRH cells. However, recent evidence found that restoring leptin to physiological levels did not restore GnRH function in three different models of negative energy balance. This suggests that although leptin may be an important permissive signal for reproductive function as indicated by many years of research, factors other than leptin must critically contribute to negative energy balance-induced reproductive inhibition. This review will focus on emerging candidates for the integration of metabolic status and reproductive function during negative energy balance.
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Affiliation(s)
- Cadence True
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science UniversityBeaverton, OR, USA
| | - Kevin L. Grove
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science UniversityBeaverton, OR, USA
| | - M. Susan Smith
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science UniversityBeaverton, OR, USA
- *Correspondence: M. Susan Smith, Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, 505 NW 185th Avenue, Beaverton, OR 97006, USA. e-mail:
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