1
|
Sáenz de Miera C, Bellefontaine N, Allen SJ, Myers MG, Elias CF. Glutamate neurotransmission from leptin receptor cells is required for typical puberty and reproductive function in female mice. eLife 2024; 13:RP93204. [PMID: 39007235 PMCID: PMC11249761 DOI: 10.7554/elife.93204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/16/2024] Open
Abstract
The hypothalamic ventral premammillary nucleus (PMv) is a glutamatergic nucleus essential for the metabolic control of reproduction. However, conditional deletion of leptin receptor long form (LepRb) in vesicular glutamate transporter 2 (Vglut2) expressing neurons results in virtually no reproductive deficits. In this study, we determined the role of glutamatergic neurotransmission from leptin responsive PMv neurons on puberty and fertility. We first assessed if stimulation of PMv neurons induces luteinizing hormone (LH) release in fed adult females. We used the stimulatory form of designer receptor exclusively activated by designer drugs (DREADDs) in LeprCre (LepRb-Cre) mice. We collected blood sequentially before and for 1 hr after intravenous clozapine-N-oxide injection. LH level increased in animals correctly targeted to the PMv, and LH level was correlated to the number of Fos immunoreactive neurons in the PMv. Next, females with deletion of Slc17a6 (Vglut2) in LepRb neurons (LeprΔVGlut2) showed delayed age of puberty, disrupted estrous cycles, increased gonadotropin-releasing hormone (GnRH) concentration in the axon terminals, and disrupted LH secretion, suggesting impaired GnRH release. To assess if glutamate is required for PMv actions in pubertal development, we generated a Cre-induced reexpression of endogenous LepRb (LeprloxTB) with concomitant deletion of Slc17a6 (Vglut2flox) mice. Rescue of Lepr and deletion of Slc17a6 in the PMv was obtained by stereotaxic injection of an adeno-associated virus vector expressing Cre recombinase. Control LeprloxTB mice with PMv LepRb rescue showed vaginal opening, follicle maturation, and became pregnant, while LeprloxTB;Vglut2flox mice showed no pubertal development. Our results indicate that glutamatergic neurotransmission from leptin sensitive neurons regulates the reproductive axis, and that leptin action on pubertal development via PMv neurons requires Vglut2.
Collapse
Affiliation(s)
- Cristina Sáenz de Miera
- Department of Molecular and Integrative Physiology, University of Michigan–Ann ArborAnn ArborUnited States
| | - Nicole Bellefontaine
- Department of Molecular and Integrative Physiology, University of Michigan–Ann ArborAnn ArborUnited States
| | - Susan J Allen
- Department of Molecular and Integrative Physiology, University of Michigan–Ann ArborAnn ArborUnited States
| | - Martin G Myers
- Department of Molecular and Integrative Physiology, University of Michigan–Ann ArborAnn ArborUnited States
- Elizabeth W. Caswell Diabetes Institute, University of Michigan–Ann ArborAnn ArborUnited States
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan–Ann ArborAnn ArborUnited States
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan–Ann ArborAnn ArborUnited States
- Elizabeth W. Caswell Diabetes Institute, University of Michigan–Ann ArborAnn ArborUnited States
- Department of Obstetrics and Gynecology, University of Michigan–Ann ArborAnn ArborUnited States
| |
Collapse
|
2
|
Hristov M, Landzhov B, Yakimova K. Effect of leptin on nitrergic neurons in the lateral hypothalamic area and the supraoptic nucleus of rats. Biotech Histochem 2024; 99:125-133. [PMID: 38533595 DOI: 10.1080/10520295.2024.2335167] [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] [Indexed: 03/28/2024] Open
Abstract
The adipocyte-derived hormone, leptin, plays a key role in the maintenance of energy homeostasis. Leptin binds to the long form of its receptor, which is predominantly expressed in various hypothalamic regions, including the lateral hypothalamic area (LH) and supraoptic nucleus (SO). Several studies have suggested that leptin directly activates neuronal nitric oxide synthase, leading to increased nitric oxide production. We used histochemistry for nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) as a marker for nitric oxide synthase activity and assessed the effect of leptin on nitrergic neurons in the LH and SO of rats. We found that intraperitoneal administration of leptin led to a significant increase in the number of NADPH-d-positive neurons in the LH and SO. In addition, the intensity (optical density) of NADPH-d staining in LH and SO neurons was significantly elevated in rats that received leptin compared with saline-treated rats. These findings suggest that nitrergic neurons in the LH and SO may be implicated in mediating the central effects of leptin.
Collapse
Affiliation(s)
- Milen Hristov
- Department of Pharmacology and Toxicology, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Boycho Landzhov
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Krassimira Yakimova
- Department of Pharmacology and Toxicology, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| |
Collapse
|
3
|
Anderson GM, Hill JW, Kaiser UB, Navarro VM, Ong KK, Perry JRB, Prevot V, Tena-Sempere M, Elias CF. Metabolic control of puberty: 60 years in the footsteps of Kennedy and Mitra's seminal work. Nat Rev Endocrinol 2024; 20:111-123. [PMID: 38049643 PMCID: PMC10843588 DOI: 10.1038/s41574-023-00919-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/19/2023] [Indexed: 12/06/2023]
Abstract
An individual's nutritional status has a powerful effect on sexual maturation. Puberty onset is delayed in response to chronic energy insufficiency and is advanced under energy abundance. The consequences of altered pubertal timing for human health are profound. Late puberty increases the chances of cardiometabolic, musculoskeletal and neurocognitive disorders, whereas early puberty is associated with increased risks of adult obesity, type 2 diabetes mellitus, cardiovascular diseases and various cancers, such as breast, endometrial and prostate cancer. Kennedy and Mitra's trailblazing studies, published in 1963 and using experimental models, were the first to demonstrate that nutrition is a key factor in puberty onset. Building on this work, the field has advanced substantially in the past decade, which is largely due to the impressive development of molecular tools for experimentation and population genetics. In this Review, we discuss the latest advances in basic and translational sciences underlying the nutritional and metabolic control of pubertal development, with a focus on perspectives and future directions.
Collapse
Affiliation(s)
- Greg M Anderson
- Centre for Neuroendocrinology, University of Otago, Dunedin, New Zealand
- Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - Jennifer W Hill
- Department of Physiology and Pharmacology, University of Toledo, Toledo, OH, USA
- Center for Diabetes and Endocrine Research, University of Toledo, Toledo, OH, USA
| | - Ursula B Kaiser
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Victor M Navarro
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ken K Ong
- Metabolic Research Laboratory, Wellcome-MRC Institute of Metabolic Science, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - John R B Perry
- Metabolic Research Laboratory, Wellcome-MRC Institute of Metabolic Science, University of Cambridge School of Clinical Medicine, Cambridge, UK
- MRC Epidemiology Unit, Wellcome-MRC Institute of Metabolic Science, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - Vincent Prevot
- University of Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S 1172, Lille, France
- European Genomic Institute for Diabetes (EGID), Lille, France
| | - Manuel Tena-Sempere
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Cordoba, Spain.
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Cordoba, Spain.
| | - Carol F Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA.
- Department of Obstetrics & Gynecology, University of Michigan, Ann Arbor, MI, USA.
- Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
4
|
Cara AL, Burger LL, Beekly BG, Allen SJ, Henson EL, Auchus RJ, Myers MG, Moenter SM, Elias CF. Deletion of Androgen Receptor in LepRb Cells Improves Estrous Cycles in Prenatally Androgenized Mice. Endocrinology 2023; 164:bqad015. [PMID: 36683455 PMCID: PMC10091504 DOI: 10.1210/endocr/bqad015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 01/13/2023] [Accepted: 01/18/2023] [Indexed: 01/24/2023]
Abstract
Androgens are steroid hormones crucial for sexual differentiation of the brain and reproductive function. In excess, however, androgens may decrease fertility as observed in polycystic ovary syndrome, a common endocrine disorder characterized by oligo/anovulation and/or polycystic ovaries. Hyperandrogenism may also disrupt energy homeostasis, inducing higher central adiposity, insulin resistance, and glucose intolerance, which may exacerbate reproductive dysfunction. Androgens bind to androgen receptors (ARs), which are expressed in many reproductive and metabolic tissues, including brain sites that regulate the hypothalamo-pituitary-gonadal axis and energy homeostasis. The neuronal populations affected by androgen excess, however, have not been defined. We and others have shown that, in mice, AR is highly expressed in leptin receptor (LepRb) neurons, particularly in the arcuate (ARH) and the ventral premammillary nuclei (PMv). Here, we assessed if LepRb neurons, which are critical in the central regulation of energy homeostasis and exert permissive actions on puberty and fertility, have a role in the pathogenesis of female hyperandrogenism. Prenatally androgenized (PNA) mice lacking AR in LepRb cells (LepRbΔAR) show no changes in body mass, body composition, glucose homeostasis, or sexual maturation. They do show, however, a remarkable improvement of estrous cycles combined with normalization of ovary morphology compared to PNA controls. Our findings indicate that the prenatal androgenization effects on adult reproductive physiology (ie, anestrus and anovulation) are mediated by a subpopulation of LepRb neurons directly sensitive to androgens. They also suggest that the effects of hyperandrogenism on sexual maturation and reproductive function in adult females are controlled by distinct neural circuits.
Collapse
Affiliation(s)
- Alexandra L Cara
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Laura L Burger
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Bethany G Beekly
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Susan J Allen
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Emily L Henson
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Richard J Auchus
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Martin G Myers
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Suzanne M Moenter
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Carol F Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan 48109, USA
| |
Collapse
|
5
|
Chen X, Xiao Z, Cai Y, Huang L, Chen C. Hypothalamic mechanisms of obesity-associated disturbance of hypothalamic-pituitary-ovarian axis. Trends Endocrinol Metab 2022; 33:206-217. [PMID: 35063326 DOI: 10.1016/j.tem.2021.12.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 12/20/2022]
Abstract
Ovulatory disorders are the most common clinical feature exhibited among obese women. Initiation of ovulation physiologically requires a surge of gonadotropin-releasing hormone (GnRH) released from GnRH neurons located in the hypothalamus. These GnRH neurons receive metabolic signals from circulation and vicinal neurons to regulate GnRH release. Leptin acts indirectly on GnRH via adjacent leptin receptor (LEPR)-expressing neurons such as proopiomelanocortin (POMC), neuropeptide Y (NPY)/agouti-related peptide (AgRP), and neuronal nitric oxide (NO) synthase (nNOS) neurons to affect GnRH neuronal activities. Additionally, hypothalamic inflammation also affects ovulation independent of obesity. Therefore, this review focuses on hypothalamic mechanisms that underlie the disturbance of hypothalamic-pituitary-ovarian (HPO) axis during obesity with an attempt to promote future studies and/or novel therapeutic strategies for ovulatory disorders in obesity.
Collapse
Affiliation(s)
- Xiaolin Chen
- Department of Endocrinology, Renmin Hospital of Wuhan University, Wuchang District, Wuhan, Hubei, China
| | - Zhuoni Xiao
- Reproductive Medical Center, Renmin Hospital of Wuhan University, Wuchang District, Wuhan, Hubei, China
| | - Yuli Cai
- Department of Endocrinology, Renmin Hospital of Wuhan University, Wuchang District, Wuhan, Hubei, China
| | - Lili Huang
- School of Biomedical Science, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Chen Chen
- School of Biomedical Science, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia.
| |
Collapse
|
6
|
Moinho TM, Tavares MR, Campos AM, Frazão R, Metzger M, Donato J. Simple method to induce denaturation of fluorescent proteins in free-floating brain slices. J Neurosci Methods 2022; 371:109500. [DOI: 10.1016/j.jneumeth.2022.109500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 10/19/2022]
|
7
|
Quaresma PGF, Wasinski F, Mansano NS, Furigo IC, Teixeira PDS, Gusmao DO, Frazao R, Donato J. Leptin Receptor Expression in GABAergic Cells is Not Sufficient to Normalize Metabolism and Reproduction in Mice. Endocrinology 2021; 162:6353267. [PMID: 34402859 DOI: 10.1210/endocr/bqab168] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Indexed: 12/12/2022]
Abstract
Previous studies indicate that leptin receptor (LepR) expression in GABAergic neurons is necessary for the biological effects of leptin. However, it is not clear whether LepR expression only in GABAergic neurons is sufficient to prevent the metabolic and neuroendocrine imbalances caused by LepR deficiency. In the present study, we produced mice that express the LepR exclusively in GABAergic cells (LepRVGAT mice) and compared them with wild-type (LepR+/+) and LepR-deficient (LepRNull/Null) mice. Although LepRVGAT mice showed a pronounced reduction in body weight and fat mass, as compared with LepRNull/Null mice, male and female LepRVGAT mice exhibited an obese phenotype relative to LepR+/+ mice. Food intake was normalized in LepRVGAT mice; however, LepRVGAT mice still exhibited lower energy expenditure in both sexes and reduced ambulatory activity in the females, compared with LepR+/+ mice. The acute anorexigenic effect of leptin and hedonic feeding were normalized in LepRVGAT mice despite the hyperleptinemia they present. Although LepRVGAT mice showed improved glucose homeostasis compared with LepRNull/Null mice, both male and female LepRVGAT mice exhibited insulin resistance. In contrast, LepR expression only in GABAergic cells was sufficient to normalize the density of agouti-related peptide (AgRP) and α-MSH immunoreactive fibers in the paraventricular nucleus of the hypothalamus. However, LepRVGAT mice exhibited reproductive dysfunctions, including subfertility in males and alterations in the estrous cycle of females. Taken together, our findings indicate that LepR expression in GABAergic cells, although critical to the physiology of leptin, is insufficient to normalize several metabolic aspects and the reproductive function in mice.
Collapse
Affiliation(s)
- Paula G F Quaresma
- Universidade de São Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, São Paulo, SP, 05508-000, Brazil
| | - Frederick Wasinski
- Universidade de São Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, São Paulo, SP, 05508-000, Brazil
| | - Naira S Mansano
- Departamento de Anatomia, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil
| | - Isadora C Furigo
- Universidade de São Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, São Paulo, SP, 05508-000, Brazil
| | - Pryscila D S Teixeira
- Universidade de São Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, São Paulo, SP, 05508-000, Brazil
| | - Daniela O Gusmao
- Universidade de São Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, São Paulo, SP, 05508-000, Brazil
| | - Renata Frazao
- Departamento de Anatomia, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil
| | - Jose Donato
- Universidade de São Paulo, Instituto de Ciencias Biomedicas, Departamento de Fisiologia e Biofisica, São Paulo, SP, 05508-000, Brazil
| |
Collapse
|
8
|
Prashar V, Arora T, Singh R, Sharma A, Parkash J. Interplay of KNDy and nNOS neurons: A new possible mechanism of GnRH secretion in the adult brain. Reprod Biol 2021; 21:100558. [PMID: 34509713 DOI: 10.1016/j.repbio.2021.100558] [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] [Received: 02/18/2021] [Revised: 08/25/2021] [Accepted: 08/28/2021] [Indexed: 02/07/2023]
Abstract
Reproduction in mammals is favoured when there is sufficient energy available to permit the survival of offspring. Neuronal nitric oxide synthase expressing neurons produce nitric oxide in the proximity of the gonadotropin-releasing hormone neurons in the preoptic region. nNOS neurons are an integral part of the neuronal network controlling ovarian cyclicity and ovulation. Nitric oxide can directly regulate the activity of the GnRH neurons and play a vital role neuroendocrine axis. Kisspeptin neurons are essential for the GnRH pulse and surge generation. The anteroventral periventricular nucleus (AVPV), kisspeptin neurons are essential for GnRH surge generation. KNDy neurons are present in the hypothalamus's arcuate nucleus (ARC), co-express NKB and dynorphin, essential for GnRH pulse generation. Kisspeptin-neurokinin B-dynorphin (KNDy) neuroendocrine molecules of the hypothalamus are key components in the central control of GnRH secretion. The hypothalamic neurons kisspeptin, KNDy, nitric oxide synthase (NOS), and other mediators such as leptin, adiponectin, and ghrelin, play an active role in attaining puberty. Kisspeptin signalling is mediated by NOS, which further results in the secretion of GnRH. Neuronal nitric oxide is critical for attaining puberty, but its direct role in adult GnRH secretion is poorly understood. This review mainly focuses on the role of nNOS and its interplay with KNDy neurons in the hormonal regulation of reproduction.
Collapse
Affiliation(s)
- Vikash Prashar
- Department of Zoology, School of Basic and Applied Sciences, Central University Punjab, Ghudda, Bathinda, 151401, Punjab, India
| | - Tania Arora
- Department of Zoology, School of Basic and Applied Sciences, Central University Punjab, Ghudda, Bathinda, 151401, Punjab, India
| | - Randeep Singh
- Department of Zoology, School of Basic and Applied Sciences, Central University Punjab, Ghudda, Bathinda, 151401, Punjab, India
| | - Arti Sharma
- Department of Computational Biology, School of Basic and Applied Sciences, Central University Punjab, Ghudda, Bathinda, 151401, Punjab, India
| | - Jyoti Parkash
- Department of Zoology, School of Basic and Applied Sciences, Central University Punjab, Ghudda, Bathinda, 151401, Punjab, India.
| |
Collapse
|
9
|
Lyra E Silva NM, Gonçalves RA, Pascoal TA, Lima-Filho RAS, Resende EDPF, Vieira ELM, Teixeira AL, de Souza LC, Peny JA, Fortuna JTS, Furigo IC, Hashiguchi D, Miya-Coreixas VS, Clarke JR, Abisambra JF, Longo BM, Donato J, Fraser PE, Rosa-Neto P, Caramelli P, Ferreira ST, De Felice FG. Pro-inflammatory interleukin-6 signaling links cognitive impairments and peripheral metabolic alterations in Alzheimer's disease. Transl Psychiatry 2021; 11:251. [PMID: 33911072 PMCID: PMC8080782 DOI: 10.1038/s41398-021-01349-z] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/25/2021] [Accepted: 03/19/2021] [Indexed: 12/22/2022] Open
Abstract
Alzheimer's disease (AD) is associated with memory impairment and altered peripheral metabolism. Mounting evidence indicates that abnormal signaling in a brain-periphery metabolic axis plays a role in AD pathophysiology. The activation of pro-inflammatory pathways in the brain, including the interleukin-6 (IL-6) pathway, comprises a potential point of convergence between memory dysfunction and metabolic alterations in AD that remains to be better explored. Using T2-weighted magnetic resonance imaging (MRI), we observed signs of probable inflammation in the hypothalamus and in the hippocampus of AD patients when compared to cognitively healthy control subjects. Pathological examination of post-mortem AD hypothalamus revealed the presence of hyperphosphorylated tau and tangle-like structures, as well as parenchymal and vascular amyloid deposits surrounded by astrocytes. T2 hyperintensities on MRI positively correlated with plasma IL-6, and both correlated inversely with cognitive performance and hypothalamic/hippocampal volumes in AD patients. Increased IL-6 and suppressor of cytokine signaling 3 (SOCS3) were observed in post-mortem AD brains. Moreover, activation of the IL-6 pathway was observed in the hypothalamus and hippocampus of AD mice. Neutralization of IL-6 and inhibition of the signal transducer and activator of transcription 3 (STAT3) signaling in the brains of AD mouse models alleviated memory impairment and peripheral glucose intolerance, and normalized plasma IL-6 levels. Collectively, these results point to IL-6 as a link between cognitive impairment and peripheral metabolic alterations in AD. Targeting pro-inflammatory IL-6 signaling may be a strategy to alleviate memory impairment and metabolic alterations in the disease.
Collapse
Affiliation(s)
- Natalia M Lyra E Silva
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Rafaella A Gonçalves
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Tharick A Pascoal
- Translational Neuroimaging Laboratory, McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Montreal, Quebec, Canada
| | - Ricardo A S Lima-Filho
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Elisa de Paula França Resende
- Behavioral and Cognitive Neurology Research Group, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
- Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Erica L M Vieira
- Centre of Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Antonio L Teixeira
- Neuropsychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
- Santa Casa BH Ensino e Pesquisa, Belo Horizonte, MG, Brazil
| | - Leonardo C de Souza
- Behavioral and Cognitive Neurology Research Group, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
- Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Julyanna A Peny
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Juliana T S Fortuna
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Isadora C Furigo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Debora Hashiguchi
- Department of Physiology, Federal University of São Paulo, São Paulo, SP, Brazil
| | - Vivian S Miya-Coreixas
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Julia R Clarke
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Jose F Abisambra
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease University of Florida, Gainesville, FL, USA
| | - Beatriz M Longo
- Department of Physiology, Federal University of São Paulo, São Paulo, SP, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Paul E Fraser
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Montreal, Quebec, Canada
| | - Paulo Caramelli
- Behavioral and Cognitive Neurology Research Group, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sergio T Ferreira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
| | - Fernanda G De Felice
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.
- Department of Psychiatry, Queen's University, Kingston, ON, Canada.
- Department of Biomedical and Molecuar Sciences, Queen's University, Kingston, ON, Canada.
| |
Collapse
|
10
|
Chachlaki K, Prevot V. Nitric oxide signalling in the brain and its control of bodily functions. Br J Pharmacol 2020; 177:5437-5458. [PMID: 31347144 PMCID: PMC7707094 DOI: 10.1111/bph.14800] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 07/10/2019] [Accepted: 07/19/2019] [Indexed: 02/06/2023] Open
Abstract
Nitric oxide (NO) is a versatile molecule that plays key roles in the development and survival of mammalian species by endowing brain neuronal networks with the ability to make continual adjustments to function in response to moment-to-moment changes in physiological input. Here, we summarize the progress in the field and argue that NO-synthetizing neurons and NO signalling in the brain provide a core hub for integrating sensory- and homeostatic-related cues, control key bodily functions, and provide a potential target for new therapeutic opportunities against several neuroendocrine and behavioural abnormalities.
Collapse
Affiliation(s)
- Konstantina Chachlaki
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine BrainJean‐Pierre Aubert Research Centre, UMR‐S 1172LilleFrance
- School of MedicineUniversity of LilleLilleFrance
- CHU LilleFHU 1,000 days for HealthLilleFrance
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine BrainJean‐Pierre Aubert Research Centre, UMR‐S 1172LilleFrance
- School of MedicineUniversity of LilleLilleFrance
- CHU LilleFHU 1,000 days for HealthLilleFrance
| |
Collapse
|
11
|
Hristov M, Landzhov B, Yakimova K. Cafeteria diet-induced obesity reduces leptin-stimulated NADPH-diaphorase reactivity in the hypothalamic arcuate nucleus of rats. Acta Histochem 2020; 122:151616. [PMID: 33066838 DOI: 10.1016/j.acthis.2020.151616] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/08/2020] [Accepted: 08/17/2020] [Indexed: 02/07/2023]
Abstract
Leptin is an adipokine that plays an important role in the regulation of energy homeostasis. The failure of endogenous and exogenous leptin to mediate its effects (for example, at suppressing appetite and decreasing body weight) has been termed leptin resistance. Hyperleptinemia and leptin resistance can be well demonstrated in animals in which obesity is induced by consumption of a palatable, high-calorie diet (e.g., cafeteria diet-induced obesity). Since leptin receptor signaling is known to be impaired in the hypothalamic arcuate nucleus (ARC) of obese rodents, we investigated the effect of leptin on nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) reactivity in the ARC of male Wistar rats with cafeteria diet-induced obesity. Our results have shown that after intraperitoneal administration of leptin, the number of NADPH-d positive neurons in the ARC was significantly lower in obese rats compared with that observed in normal weight rats. Additionally, we have found that leptin-induced NADPH-d staining in ARC neurons and the adjacent ependyma was decreased in obese rats. The results presented here suggest that the ability of leptin to activate nitric oxide synthase in neurons within the ARC as well as tanycytes and ependymal cells of the third ventricle is reduced in rats made obese by a cafeteria diet. We speculate that impairment in leptin-induced NO production presents a potential mechanism, involved in the pathogenesis of obesity and obesity-related disease states.
Collapse
Affiliation(s)
- Milen Hristov
- Department of Pharmacology and Toxicology, Faculty of Medicine, Medical University of Sofia, 2 "Zdrave" St., 1431 Sofia, Bulgaria.
| | - Boycho Landzhov
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, Medical University of Sofia, 2 "Zdrave" St., 1431 Sofia, Bulgaria
| | - Krassimira Yakimova
- Department of Pharmacology and Toxicology, Faculty of Medicine, Medical University of Sofia, 2 "Zdrave" St., 1431 Sofia, Bulgaria
| |
Collapse
|
12
|
Campos AMP, Teixeira PDS, Wasinski F, Klein MO, Bittencourt JC, Metzger M, Donato J. Differences between rats and mice in the leptin action on the paraventricular nucleus of the hypothalamus: Implications for the regulation of the hypothalamic-pituitary-thyroid axis. J Neuroendocrinol 2020; 32:e12895. [PMID: 32840013 DOI: 10.1111/jne.12895] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 07/03/2020] [Accepted: 07/20/2020] [Indexed: 12/23/2022]
Abstract
Previous studies indicate that leptin regulates the hypothalamic-pituitary-thyroid (HPT) axis via direct and indirect mechanisms. The indirect mechanism involves leptin action in pro-opiomelanocortin (POMC)- and agouti-related peptide (AgRP)-expressing neurones. These cells innervate the paraventricular nucleus of the hypothalamus (PVH) where they modulate hypophysiotrophic thyrotrophin-releasing hormone (TRH)-producing neurones. The direct mechanism involves the expression of leptin receptor (LepR) in a subpopulation of PVH TRH neurones. However, to our knowledge, the existence of LepR in PVH TRH neurones of mice has not been clearly confirmed. Therefore, we investigated possible species-specific differences between rats and mice with respect to the mechanisms recruited by leptin to regulate the HPT axis. We observed that an acute leptin injection induced phosphorylated signal transducer and activator of transcription 3 (pSTAT3), a marker of leptin-responsive cells, in 46.2 ± 8.0% of PVH proTRH immunoreactive neurones in rats. By contrast, an insignificant number of proTRH positive neurones in the mouse PVH co-expressed leptin-induced pSTAT3 or LepR. Similarly, central leptin injection increased the percentage of PVH proTRH neurones containing cAMP response element-binding protein phosphorylation in rats, but not in mice. We investigated the innervation of AgRP and POMC axons in the PVH and observed that rats exhibited a denser POMC innervation in the PVH compared to mice, whereas rats and mice showed similar density of AgRP axons in the PVH. In conclusion, rats and mice exhibit important species-specific differences in the direct and indirect mechanisms used by leptin to regulate the HPT axis.
Collapse
Affiliation(s)
- Ana M P Campos
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Pryscila D S Teixeira
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Frederick Wasinski
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Marianne O Klein
- Departamento de Anatomia, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Jackson C Bittencourt
- Departamento de Anatomia, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Martin Metzger
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| | - Jose Donato
- Departamento de Fisiologia e Biofísica, Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Sao Paulo, Brazil
| |
Collapse
|
13
|
Guerra DD, Bok R, Cari EL, Nicholas C, Orlicky DJ, Johnson J, Hurt KJ. Effect of neuronal nitric oxide synthase serine-1412 phosphorylation on hypothalamic-pituitary-ovarian function and leptin response. Biol Reprod 2020; 102:1281-1289. [PMID: 32101284 DOI: 10.1093/biolre/ioaa025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 01/24/2020] [Accepted: 02/25/2020] [Indexed: 01/16/2023] Open
Abstract
Hypothalamic neuronal nitric oxide synthase (nNOS) potentiates adult female fertility in rodents by stimulating gonadotropin releasing hormone (GnRH) secretion, which in turn promotes luteinizing hormone (LH) release and ovulation. The mechanism of hypothalamic nNOS activation is not clear but could be via nNOS serine1412 (S1412) phosphorylation, which increases nNOS activity and physiologic NO effects in other organ systems. In female rodents, hypothalamic nNOS S1412 phosphorylation reportedly increases during proestrus or upon acute leptin exposure during diestrus. To determine if nNOS S1412 regulates female reproduction in mice, we compared the reproductive anatomy, estrous cycle duration and phase proportion, and fecundity of wild-type and nNOS serine1412➔alanine (nNOSS1412A) knock-in female mice. We also measured hypothalamic GnRH and serum LH, follicle stimulating hormone (FSH), estradiol, and progesterone in diestrus mice after intraperitoneal leptin injection. Organ weights and histology were not different by genotype. Ovarian primordial follicles, antral follicles, and corpora lutea were similar for wild-type and nNOSS1412A mice. Likewise, estrous cycle duration and phase length were not different, and fecundity was unremarkable. There were no differences among genotypes for LH, FSH, estradiol, or progesterone. In contrast to prior studies, our work suggests that nNOS S1412 phosphorylation is dispensable for normal hypothalamic-pituitary-ovarian function and regular estrous cycling. These findings have important implications for current models of fertility regulation by nNOS phosphorylation.
Collapse
Affiliation(s)
- Damian D Guerra
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
| | - Rachael Bok
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
| | - Evelyn Llerena Cari
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
| | - Cari Nicholas
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
| | - David J Orlicky
- Department of Pathology, University of Colorado Denver, Aurora, CO, USA and
| | - Joshua Johnson
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
| | - K Joseph Hurt
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA
| |
Collapse
|
14
|
Leptin actions through the nitrergic system to modulate the hypothalamic expression of the kiss1 mRNA in the female rat. Brain Res 2019; 1728:146574. [PMID: 31790683 DOI: 10.1016/j.brainres.2019.146574] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/05/2019] [Accepted: 11/28/2019] [Indexed: 11/22/2022]
Abstract
Gonadotrophin-releasing hormone (GnRH) is the main controller of the reproductive axis and stimulates the synthesis and secretion of gonadotrophins. Estrogen is the main peripheral factor controlling GnRH secretion, and this action is mainly mediated by the transsynaptic pathway through nitric oxide, kisspeptin, leptin, among other factors. Kisspeptin is the most potent factor known to induce GnRH release. Nitric oxide and leptin also promote GnRH release; however, neurons expressing GnRH do not express the leptin receptor (OB-R). Leptin seems to modulate the expression of genes and proteins involved in the kisspeptin system. However, few kisspeptin-synthesizing cells in the arcuate nucleus (ARC) and few cells, if any, in the preoptic area (POA) express OB-R; this indicates an indirect mechanism of leptin action on kisspeptin. Nitric oxide is an important intermediate in the actions of leptin in the central nervous system. Thus, this work aimed to verify the numbers of nNOS cells were activated by leptin in different hypothalamic areas; the modulatory effects of the nitrergic system on the kisspeptin system; and the indirect regulatory effect of leptin on the kisspeptin system via nitric oxide. Ovariectomized rats were treated with estrogen or a vehicle and received an intracerebroventricular (i.c.v.) injection of a nitric oxide donor, leptin or neuronal nitric oxide synthase (nNOS) enzyme inhibitor. Thirty minutes after the injection, the animals were decapitated. Leptin acts directly on nitrergic neurons in different hypothalamic regions, and the effects on the ventral premammillary nucleus (PMV) and ventral dorsomedial hypothalamus (vDMH) are enhanced. The use of a nitric oxide donor or the administration of leptin stimulates the expression of the kisspeptin mRNA in the ARC of animals with or without estrogenic action; however, these changes are not observed in the POA. In addition, the action of leptin on the expression of the kisspeptin mRNA in the ARC is blocked by a nitric oxide synthesis inhibitor. We concluded that the effects of leptin on the central nervous system are at least partially mediated by the nitrergic system. Also, nitric oxide acts on the kisspeptin system by modulating the expression of the kisspeptin mRNA, and leptin at least partially modulates the kisspeptin system through the nitrergic system, particularly in the ARC.
Collapse
|
15
|
Chong PS, Poon CH, Fung ML, Guan L, Steinbusch HWM, Chan YS, Lim WL, Lim LW. Distribution of neuronal nitric oxide synthase immunoreactivity in adult male Sprague-Dawley rat brain. Acta Histochem 2019; 121:151437. [PMID: 31492421 DOI: 10.1016/j.acthis.2019.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 07/22/2019] [Accepted: 08/20/2019] [Indexed: 12/23/2022]
Abstract
Neuronal NOS (nNOS) accounts for most of the NO production in the nervous system that modulates synaptic transmission and neuroplasticity. Although previous studies have selectively described the localisation of nNOS in specific brain regions, a comprehensive distribution profile of nNOS in the brain is lacking. Here we provided a detailed morphological characterization on the rostro-caudal distribution of neurons and fibres exhibiting positive nNOS-immunoreactivity in adult Sprague-Dawley rat brain. Our results demonstrated that neurons and fibres in the brain regions that exhibited high nNOS immunoreactivity include the olfactory-related areas, intermediate endopiriform nucleus, Islands of Calleja, subfornical organ, ventral lateral geniculate nucleus, parafascicular thalamic nucleus, superior colliculus, lateral terminal nucleus, pedunculopontine tegmental nucleus, periaqueductal gray, dorsal raphe nucleus, supragenual nucleus, nucleus of the trapezoid body, and the cerebellum. Moderate nNOS immunoreactivity was detected in the cerebral cortex, caudate putamen, hippocampus, thalamus, hypothalamus, amygdala, and the spinal cord. Finally, low NOS immunoreactivity were found in the corpus callosum, fornix, globus pallidus, anterior commissure, and the dorsal hippocampal commissure. In conclusion, this study provides a comprehensive view of the morphology and localisation of nNOS immunoreactivity in the brain that would contribute to a better understanding of the role played by nNOS in the brain.
Collapse
Affiliation(s)
- Pit Shan Chong
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China
| | - Chi Him Poon
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China
| | - Man Lung Fung
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China
| | - Li Guan
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China
| | - Harry W M Steinbusch
- Department of Neuroscience and European Graduate School of Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Ying-Shing Chan
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China
| | - Wei Ling Lim
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China; Department of Biological Sciences, Sunway University, Selangor, Malaysia.
| | - Lee Wei Lim
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, PR China; Department of Biological Sciences, Sunway University, Selangor, Malaysia.
| |
Collapse
|
16
|
Becerril S, Rodríguez A, Catalán V, Ramírez B, Unamuno X, Portincasa P, Gómez-Ambrosi J, Frühbeck G. Functional Relationship between Leptin and Nitric Oxide in Metabolism. Nutrients 2019; 11:nu11092129. [PMID: 31500090 PMCID: PMC6769456 DOI: 10.3390/nu11092129] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/23/2019] [Accepted: 09/02/2019] [Indexed: 12/28/2022] Open
Abstract
Leptin, the product of the ob gene, was originally described as a satiety factor, playing a crucial role in the control of body weight. Nevertheless, the wide distribution of leptin receptors in peripheral tissues supports that leptin exerts pleiotropic biological effects, consisting of the modulation of numerous processes including thermogenesis, reproduction, angiogenesis, hematopoiesis, osteogenesis, neuroendocrine, and immune functions as well as arterial pressure control. Nitric oxide (NO) is a free radical synthesized from L-arginine by the action of the NO synthase (NOS) enzyme. Three NOS isoforms have been identified: the neuronal NOS (nNOS) and endothelial NOS (eNOS) constitutive isoforms, and the inducible NOS (iNOS). NO mediates multiple biological effects in a variety of physiological systems such as energy balance, blood pressure, reproduction, immune response, or reproduction. Leptin and NO on their own participate in multiple common physiological processes, with a functional relationship between both factors having been identified. The present review describes the functional relationship between leptin and NO in different physiological processes.
Collapse
Affiliation(s)
- Sara Becerril
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Amaia Rodríguez
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Victoria Catalán
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Beatriz Ramírez
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Xabier Unamuno
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Medical Engineering Laboratory, University of Navarra, 31008 Pamplona, Spain.
| | - Piero Portincasa
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Policlinico Hospital, 70124 Bari, Italy.
| | - Javier Gómez-Ambrosi
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Gema Frühbeck
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
- Department of Endocrinology & Nutrition, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
| |
Collapse
|
17
|
Increased NADPH-diaphorase reactivity in the hypothalamic paraventricular nucleus and tanycytes following systemic administration of leptin in rats. Acta Histochem 2019; 121:690-694. [PMID: 31227177 DOI: 10.1016/j.acthis.2019.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 12/25/2022]
Abstract
Leptin, a hormone mainly produced by adipocytes in proportion to fat mass, is a key component in the regulation of energy homeostasis and reproductive, neuroendocrine, immune, and metabolic functions. Leptin binds to the leptin receptor, which is expressed throughout the central nervous system but particularly in neurons of several nuclei of the hypothalamus, such as the arcuate nucleus (ARC) and paraventricular nucleus (PVN). It has been found that nitric oxide (NO) plays an important role in mediating effects of leptin. Since PVN and ARC neurons are known to express leptin receptors, we investigated the effects of leptin on nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) reactivity in the PVN and ARC of male Wistar rats. Our results have shown that systemic administration of leptin resulted in increased NADPH-d positive cell number in the PVN and ARC, suggesting that both the PVN and ARC may be important centers in the hypothalamus for the leptin action, mediated by increased NO production. In addition, we have also observed that hypothalamic tanycytes in the ventral portion of the third ventricle were NADPH-d positive. We speculate that leptin may affect the release of neurohormones and hypothalamic neurogenesis by activating nitric oxide synthase in hypothalamic tanycytes.
Collapse
|
18
|
Bueno D, Lima LB, Souza R, Gonçalves L, Leite F, Souza S, Furigo IC, Donato J, Metzger M. Connections of the laterodorsal tegmental nucleus with the habenular‐interpeduncular‐raphe system. J Comp Neurol 2019; 527:3046-3072. [DOI: 10.1002/cne.24729] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 06/06/2019] [Accepted: 06/07/2019] [Indexed: 02/06/2023]
Affiliation(s)
- Debora Bueno
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Leandro B. Lima
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Rudieri Souza
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Luciano Gonçalves
- Department of Human AnatomyFederal University of the Triângulo Mineiro Uberaba Brazil
| | - Fernanda Leite
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Stefani Souza
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Isadora C. Furigo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| | - Martin Metzger
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo São Paulo Brazil
| |
Collapse
|
19
|
Hill JW, Elias CF. Neuroanatomical Framework of the Metabolic Control of Reproduction. Physiol Rev 2019; 98:2349-2380. [PMID: 30109817 DOI: 10.1152/physrev.00033.2017] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A minimum amount of energy is required for basic physiological processes, such as protein biosynthesis, thermoregulation, locomotion, cardiovascular function, and digestion. However, for reproductive function and survival of the species, extra energy stores are necessary. Production of sex hormones and gametes, pubertal development, pregnancy, lactation, and parental care all require energy reserves. Thus the physiological systems that control energy homeostasis and reproductive function coevolved in mammals to support both individual health and species subsistence. In this review, we aim to gather scientific knowledge produced by laboratories around the world on the role of the brain in integrating metabolism and reproduction. We describe essential neuronal networks, highlighting key nodes and potential downstream targets. Novel animal models and genetic tools have produced substantial advances, but critical gaps remain. In times of soaring worldwide obesity and metabolic dysfunction, understanding the mechanisms by which metabolic stress alters reproductive physiology has become crucial for human health.
Collapse
Affiliation(s)
- Jennifer W Hill
- Center for Diabetes and Endocrine Research, Departments of Physiology and Pharmacology and of Obstetrics and Gynecology, University of Toledo College of Medicine , Toledo, Ohio ; and Departments of Molecular and Integrative Physiology and of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
| | - Carol F Elias
- Center for Diabetes and Endocrine Research, Departments of Physiology and Pharmacology and of Obstetrics and Gynecology, University of Toledo College of Medicine , Toledo, Ohio ; and Departments of Molecular and Integrative Physiology and of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
| |
Collapse
|
20
|
Reis MEMD, Araújo LTFD, de Andrade WMG, Resende NDS, Lima RRMD, Nascimento ESD, Costa MSMDO, Cavalcante JC. Distribution of nitric oxide synthase in the rock cavy (Kerodon rupestris) brain I: The diencephalon. Brain Res 2018; 1685:60-78. [DOI: 10.1016/j.brainres.2018.01.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/15/2018] [Accepted: 01/17/2018] [Indexed: 12/27/2022]
|
21
|
Yu S, François M, Huesing C, Münzberg H. The Hypothalamic Preoptic Area and Body Weight Control. Neuroendocrinology 2018; 106:187-194. [PMID: 28772276 PMCID: PMC6118330 DOI: 10.1159/000479875] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 07/26/2017] [Indexed: 01/09/2023]
Abstract
The preoptic area (POA) of the hypothalamus is involved in many physiological and behavioral processes thanks to its interconnections to many brain areas and ability to respond to diverse humoral factors. One main function of the POA is to manage body temperature homeostasis, e.g. in response to ambient temperature change, which is achieved in part by controlling brown adipose tissue thermogenesis. The POA is also importantly involved in modulating food intake in response to temperature change, thus making it relevant for body weight homeostasis and obesity research. POA function in body weight control is highly unexplored, and a better understanding of POA circuits and their integration into classic hypothalamic circuits that regulate energy homeostasis is expected to provide new opportunities for the scientific basis and treatment of obesity and comorbidities.
Collapse
|
22
|
Chachlaki K, Garthwaite J, Prevot V. The gentle art of saying NO: how nitric oxide gets things done in the hypothalamus. Nat Rev Endocrinol 2017. [PMID: 28621341 DOI: 10.1038/nrendo.2017.69] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The chemical signalling molecule nitric oxide (NO), which freely diffuses through aqueous and lipid environments, subserves an array of functions in the mammalian central nervous system, such as the regulation of synaptic plasticity, blood flow and neurohormone secretion. In this Review, we consider the cellular and molecular mechanisms by which NO evokes short-term and long-term changes in neuronal activity. We also highlight recent studies showing that discrete populations of neurons that synthesize NO in the hypothalamus constitute integrative systems that support life by relaying metabolic and gonadal signals to the neuroendocrine brain, and thus gate the onset of puberty and adult fertility. The putative involvement and therapeutic potential of NO in the pathophysiology of brain diseases, for which hormonal imbalances during postnatal development could be risk factors, is also discussed.
Collapse
Affiliation(s)
- Konstantina Chachlaki
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, UMR-S 1172, 1 place de Verdun, F-59000 Lille, France
- University of Lille, University Hospital Federations (FHU) 1,000 days for Health, School of Medicine, 1 place de Verdun, F-59000 Lille, France
| | - John Garthwaite
- The Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, UMR-S 1172, 1 place de Verdun, F-59000 Lille, France
- University of Lille, University Hospital Federations (FHU) 1,000 days for Health, School of Medicine, 1 place de Verdun, F-59000 Lille, France
| |
Collapse
|
23
|
Deletion of Suppressor of Cytokine Signaling 3 from Forebrain Neurons Delays Infertility and Onset of Hypothalamic Leptin Resistance in Response to a High Caloric Diet. J Neurosci 2017; 36:7142-53. [PMID: 27383590 DOI: 10.1523/jneurosci.2714-14.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 05/27/2016] [Indexed: 12/19/2022] Open
Abstract
UNLABELLED The cellular processes that cause high caloric diet (HCD)-induced infertility are poorly understood but may involve upregulation of suppressor of cytokine signaling (SOCS-3) proteins that are associated with hypothalamic leptin resistance. Deletion of SOCS-3 from brain cells is known to protect mice from diet-induced obesity, but the effects on HCD-induced infertility are unknown. We used neuron-specific SOCS3 knock-out mice to elucidate this and the effects on regional hypothalamic leptin resistance. As expected, male and female neuron-specific SOCS3 knock-out mice were protected from HCD-induced obesity. While female wild-type mice became infertile after 4 months of HCD feeding, infertility onset in knock-out females was delayed by 4 weeks. Similarly, knock-out mice had delayed leptin resistance development in the medial preoptic area and anteroventral periventricular nucleus, regions important for generation of the surge of GnRH and LH that induces ovulation. We therefore tested whether the suppressive effects of HCD on the estradiol-induced GnRH/LH surge were overcome by neuron-specific SOCS3 knock-out. Although only 20% of control HCD-mice experienced a preovulatory-like LH surge, LH surges could be induced in almost all neuron-specific SOCS3 knock-out mice on this diet. In contrast to females, HCD-fed male mice did not exhibit any fertility decline compared with low caloric diet-fed males despite their resistance to the satiety effects of leptin. These data show that deletion of SOCS3 delays the onset of leptin resistance and infertility in HCD-fed female mice, but given continued HCD feeding this state does eventually occur, presumably in response to other mechanisms inhibiting leptin signal transduction. SIGNIFICANCE STATEMENT Obesity is commonly associated with infertility in humans and other animals. Treatments for human infertility show a decreased success rate with increasing body mass index. A hallmark of obesity is an increase in circulating leptin levels; despite this, the brain responds as if there were low levels of leptin, leading to increased appetite and suppressed fertility. Here we show that leptin resistant infertility is caused in part by the leptin signaling molecule SOCS3. Deletion of SOCS3 from brain neurons delays the onset of diet-induced infertility.
Collapse
|
24
|
Mohsen Z, Sim H, Garcia-Galiano D, Han X, Bellefontaine N, Saunders TL, Elias CF. Sexually dimorphic distribution of Prokr2 neurons revealed by the Prokr2-Cre mouse model. Brain Struct Funct 2017; 222:4111-4129. [PMID: 28616754 DOI: 10.1007/s00429-017-1456-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 06/05/2017] [Indexed: 01/18/2023]
Abstract
Prokineticin receptor 2 (PROKR2) is predominantly expressed in the mammalian central nervous system. Loss-of-function mutations of PROKR2 in humans are associated with Kallmann syndrome due to the disruption of gonadotropin releasing hormone neuronal migration and deficient olfactory bulb morphogenesis. PROKR2 has been also implicated in the neuroendocrine control of GnRH neurons post-migration and other physiological systems. However, the brain circuitry and mechanisms associated with these actions have been difficult to investigate mainly due to the widespread distribution of Prokr2-expressing cells, and the lack of animal models and molecular tools. Here, we describe the generation, validation and characterization of a new mouse model that expresses Cre recombinase driven by the Prokr2 promoter, using CRISPR-Cas9 technology. Cre expression was visualized using reporter genes, tdTomato and GFP, in males and females. Expression of Cre-induced reporter genes was found in brain sites previously described to express Prokr2, e.g., the paraventricular and the suprachiasmatic nuclei, and the area postrema. The Prokr2-Cre mouse model was further validated by colocalization of Cre-induced GFP and Prokr2 mRNA. No disruption of Prokr2 expression, GnRH neuronal migration or fertility was observed. Comparative analysis of Prokr2-Cre expression in male and female brains revealed a sexually dimorphic distribution confirmed by in situ hybridization. In females, higher Cre activity was found in the medial preoptic area, ventromedial nucleus of the hypothalamus, arcuate nucleus, medial amygdala and lateral parabrachial nucleus. In males, Cre was higher in the amygdalo-hippocampal area. The sexually dimorphic pattern of Prokr2 expression indicates differential roles in reproductive function and, potentially, in other physiological systems.
Collapse
Affiliation(s)
- Zaid Mohsen
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - Hosung Sim
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - Xingfa Han
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA.,Isotope Research Lab, Sichuan Agricultural University, Ya'an, 625014, People's Republic of China
| | - Nicole Bellefontaine
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - Thomas L Saunders
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA.,University of Michigan Transgenic Animal Model Core, Ann Arbor, MI, USA
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA. .,Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
25
|
Ramos-Lobo AM, Donato J. The role of leptin in health and disease. Temperature (Austin) 2017; 4:258-291. [PMID: 28944270 DOI: 10.1080/23328940.2017.1327003] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/27/2017] [Accepted: 05/02/2017] [Indexed: 02/07/2023] Open
Abstract
Leptin is a master regulator of energy balance and body adiposity. Additionally, leptin exerts important control on glucose homeostasis, thermogenesis, autonomic nervous system and neuroendocrine axes. In metabolic diseases, such as obesity and diabetes mellitus, leptin signaling may be compromised, indicating the important role of this hormone in the etiology and pathophysiological manifestations of these conditions. In the present manuscript, we reviewed important concepts of leptin signaling, as well as about the effects of leptin on several biologic functions. We also discussed the possible therapeutic use of leptin administration and how our current obesogenic environment contributes to the development of leptin resistance. Our objective was to provide a comprehensive and state-of-the-art review about the importance of leptin to maintain the homeostasis and during pathological conditions.
Collapse
Affiliation(s)
- Angela M Ramos-Lobo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| |
Collapse
|
26
|
Lima LB, Bueno D, Leite F, Souza S, Gonçalves L, Furigo IC, Donato J, Metzger M. Afferent and efferent connections of the interpeduncular nucleus with special reference to circuits involving the habenula and raphe nuclei. J Comp Neurol 2017; 525:2411-2442. [DOI: 10.1002/cne.24217] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 03/13/2017] [Accepted: 03/15/2017] [Indexed: 02/06/2023]
Affiliation(s)
- Leandro B. Lima
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Debora Bueno
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Fernanda Leite
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Stefani Souza
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Luciano Gonçalves
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Isadora C. Furigo
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Jose Donato
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| | - Martin Metzger
- Department of Physiology & Biophysics; Institute of Biomedical Sciences, University of São Paulo; São Paulo Brazil
| |
Collapse
|
27
|
Leptin receptor-positive and leptin receptor-negative proopiomelanocortin neurons innervate an identical set of brain structures. Brain Res 2016; 1646:366-376. [DOI: 10.1016/j.brainres.2016.06.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 06/01/2016] [Accepted: 06/15/2016] [Indexed: 11/21/2022]
|
28
|
Diniz CR, Casarotto PC, Joca SR. NMDA-NO signaling in the dorsal and ventral hippocampus time-dependently modulates the behavioral responses to forced swimming stress. Behav Brain Res 2016; 307:126-36. [DOI: 10.1016/j.bbr.2016.03.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 03/18/2016] [Accepted: 03/21/2016] [Indexed: 12/17/2022]
|
29
|
Park HK, Kim SK, Kwon OY, Chung JH, Lee SK. Analysis between nitric oxide synthase 1 (NOS1) and risk of obesity. Mol Cell Toxicol 2016. [DOI: 10.1007/s13273-016-0026-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
30
|
Distribution of growth hormone-responsive cells in the mouse brain. Brain Struct Funct 2016; 222:341-363. [PMID: 27072946 DOI: 10.1007/s00429-016-1221-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 03/30/2016] [Indexed: 12/31/2022]
Abstract
Growth hormone (GH) exerts important biological effects primarily related to growth and metabolism. However, the role of GH signaling in the brain is still elusive. To better understand GH functions in the brain, we mapped the distribution of GH-responsive cells and identified the receptors involved in GH central effects. For this purpose, mice received an acute intraperitoneal challenge with specific ligands of the GH receptor (mouse GH), prolactin receptor (prolactin) or both receptors (human GH), and their brains were subsequently processed immunohistochemically to detect the phosphorylated form of STAT5 (pSTAT5). GH induced pSTAT5 immunoreactivity in neurons, but not in astroglial cells of numerous brain regions, including the cerebral cortex, nucleus accumbens, hippocampus, septum and amygdala. The most prominent populations of GH-responsive neurons were located in hypothalamic areas, including several preoptic divisions, and the supraoptic, paraventricular, suprachiasmatic, periventricular, arcuate, ventromedial, dorsomedial, tuberal, posterior and ventral premammillary nuclei. Interestingly, many brainstem structures also exhibited GH-responsive cells. Experiments combining immunohistochemistry for pSTAT5 and in situ hybridization for GH and prolactin receptors revealed that human GH induced pSTAT5 in most, but not all, brain regions through both prolactin and GH receptors. Additionally, males and females exhibited a similar number of GH-responsive cells in forebrain structures known to be sexually dimorphic. In summary, we found GH-responsive cells primarily distributed in brain regions implicated in neurovegetative, emotional/motivational and cognitive functions. Our findings deepen the understanding of GH signaling in the brain and suggest that central GH signaling is likely more ample and complex than formerly recognized.
Collapse
|
31
|
Candlish M, Angelis RD, Götz V, Boehm U. Gene Targeting in Neuroendocrinology. Compr Physiol 2015; 5:1645-76. [DOI: 10.1002/cphy.c140079] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
32
|
Garcia-Galiano D, Allen SJ, Elias CF. Role of the adipocyte-derived hormone leptin in reproductive control. Horm Mol Biol Clin Investig 2015; 19:141-9. [PMID: 25390022 DOI: 10.1515/hmbci-2014-0017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 04/29/2014] [Indexed: 12/11/2022]
Abstract
Achievement of sexual maturation and maintenance of fertility in adulthood are functions that are sensitive to the metabolic status of the organism, particularly the magnitude of fat reserves. In this sense, the adipocyte-derived hormone, leptin, plays a major role in linking metabolic cues and the control of multiple neuroendocrine axes. The hypothalamus is a key site mediating leptin actions, including those involved in the modulation of the hypothalamus-pituitary-gonads (HPG) axis at different stages of development and in different environmental conditions. In the present review, we provide an update of the role of leptin in reproduction and discuss its interactions with neurons, neurotransmitters and downstream targets of the reproductive axis, with a special emphasis on the actions of leptin in the central nervous system. We hope this review will contribute to the understanding of the mechanisms whereby metabolic signals, especially leptin, influence the reproductive neuroendocrine axis modulating its activity in different nutritional states. Special attention will be given to recent advances in the identification of key hypothalamic sites and signaling pathways relevant to leptin's action in reproductive control.
Collapse
|
33
|
Del Bianco-Borges B, Franci C. Estrogen-dependent post-translational change in the nitric oxide system may mediate the leptin action on LH and prolactin secretion. Brain Res 2015; 1604:62-73. [DOI: 10.1016/j.brainres.2015.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 01/25/2015] [Accepted: 02/01/2015] [Indexed: 11/25/2022]
|
34
|
da Silva RP, Zampieri TT, Pedroso JAB, Nagaishi VS, Ramos-Lobo AM, Furigo IC, Câmara NO, Frazão R, Donato J. Leptin resistance is not the primary cause of weight gain associated with reduced sex hormone levels in female mice. Endocrinology 2014; 155:4226-36. [PMID: 25144922 DOI: 10.1210/en.2014-1276] [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
Several studies have shown that estrogens mimic leptin's effects on energy balance regulation. However, the findings regarding the consequences of reduced sex hormone levels on leptin sensitivity are divergent. In the present study, we employed different experimental paradigms to elucidate the interaction between estrogens, leptin, and energy balance regulation. We confirmed previous reports showing that ovariectomy caused a reduction in locomotor activity and energy expenditure leading mice to obesity and glucose intolerance. However, the acute and chronic anorexigenic effects of leptin were preserved in ovariectomized (OVX) mice despite their increased serum leptin levels. We studied hypothalamic gene expression at different time points after ovariectomy and observed that changes in the expression of genes involved in leptin resistance (suppressors of cytokine signaling and protein-tyrosine phosphatases) did not precede the early onset of obesity in OVX mice. On the contrary, reduced sex hormone levels caused an up-regulation of the long form of the leptin receptor (LepR), resulting in increased activation of leptin signaling pathways in OVX leptin-treated animals. The up-regulation of the LepR was observed in long-term OVX mice (30 d or 24 wk after ovariectomy) but not 7 days after the surgery. In addition, we observed a progressive decrease in the coexpression of LepR and estrogen receptor-α in the hypothalamus after the ovariectomy, resulting in a low percentage of dual-labeled cells in OVX mice. Taken together, our findings suggest that the weight gain caused by reduced sex hormone levels is not primarily caused by induction of a leptin-resistance state.
Collapse
Affiliation(s)
- Regina P da Silva
- Department of Anatomy (R.P.d.S., R.F.), Institute of Biomedical Sciences, University of São Paulo, São Paulo, 05508-000 Brazil; Department of Physiology and Biophysics (T.T.Z., J.A.B.P., V.S.N., A.M.R.-L., I.C.F., J.D.), Institute of Biomedical Sciences, University of São Paulo, São Paulo, 05508-000 Brazil; and Department of Immunology (N.O.C.), Institute of Biomedical Sciences, University of São Paulo, São Paulo, 05508-000 Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Abstract
The association between leptin and reproduction originated with the leptin-mediated correction of sterility in ob/ob mice and initiation of reproductive function in normal female mice. The uncovering of a central leptin pathway regulating food intake prompted the dissection of neuroendocrine mechanisms involving leptin in the metabolic control of reproduction. The absence of leptin receptors on GnRH neurons incited a search for intermediary neurons situated between leptin-responsive and GnRH neurons. This review addresses the most significant findings that have furthered our understanding of recent progress in this new field. The role of leptin in puberty was impacted by the discovery of neurons that co-express kisspeptin, neurokinin B, and dynorphin and these could act as leptin intermediates. Furthermore, the identification of first-order leptin-responsive neurons in the premammilary ventral nucleus and other brain regions opens new avenues to explore their relationship to GnRH neurons. Central to these advances is the unveiling that agouti-related protein/neuropeptide Y neurons project onto GnRH and kisspeptin neurons, allowing for a crosstalk between food intake and reproduction. Finally, while puberty is a state of leptin sensitivity, mid-gestation represents a state of leptin resistance aimed at building energy stores to sustain pregnancy and lactation. The mechanisms underlying leptin resistance in pregnancy have lagged; however, the establishment of this natural state is significant. Reproduction and energy balance are tightly controlled and backed up by redundant mechanisms that are critical for the survival of our species. It will be the goal of the following decade to shed new light on these complex and essential pathways.
Collapse
Affiliation(s)
- Farid F Chehab
- Department of Laboratory MedicineUniversity of California, San Francisco, San Francisco, California 94132, USA
| |
Collapse
|
36
|
Leshan RL, Pfaff DW. The hypothalamic ventral premammillary nucleus: A key site in leptin's regulation of reproduction. J Chem Neuroanat 2014; 61-62:239-47. [PMID: 25172030 DOI: 10.1016/j.jchemneu.2014.08.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 08/18/2014] [Accepted: 08/20/2014] [Indexed: 11/24/2022]
Abstract
Reproduction is an energy-expensive process that relies on indicators of energy availability to adjust its proper functioning. The adipokine leptin provides one such metabolic signal, with leptin receptor-expressing neurons at sites widespread within the CNS, including regions associated with the neuroendocrine reproductive axis. One substantial population lies within the hypothalamic ventral premammillary nucleus (PMv), a region itself linked to reproductive control, which may provide a strategic site for the integration of energy availability, sensory and gonadal cues. Here we review our current understanding of leptin and PMv regulation of reproduction, including emerging details about intracellular mechanisms of leptin action at this site.
Collapse
Affiliation(s)
- Rebecca L Leshan
- Laboratory of Neurobiology and Behavior, Rockefeller University, Box 275, 1230 York Avenue, New York, NY 10065, United States
| | - Donald W Pfaff
- Laboratory of Neurobiology and Behavior, Rockefeller University, Box 275, 1230 York Avenue, New York, NY 10065, United States.
| |
Collapse
|
37
|
Ratra DV, Elias CF. Chemical identity of hypothalamic neurons engaged by leptin in reproductive control. J Chem Neuroanat 2014; 61-62:233-8. [PMID: 24915437 DOI: 10.1016/j.jchemneu.2014.05.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 05/29/2014] [Accepted: 05/31/2014] [Indexed: 01/31/2023]
Abstract
The adipocyte-derived hormone leptin plays a critical role as a metabolic cue for the reproductive system. Conditions of low leptin levels observed in negative energy balance and loss-of-function mutations of leptin or leptin receptor genes are characterized by decreased fertility. In recent years, advances have been made for identifying possible hypothalamic neurons relaying leptin's neuroendocrine control of reproductive function. Studies from different laboratories have demonstrated that leptin action in the hypothalamo-pituitary-gonadal (HPG) axis is exerted via hypothalamic interneurons regulating gonadotropin-releasing hormone (GnRH) cells, oppose to direct action on GnRH neurons. Following this observation, studies focused on identifying leptin responsive interneurons. Using a Cre-loxP system to re-express or delete the leptin receptor long form (LepRb) from kisspeptin neurons, our laboratory found that leptin's action on kiss1 cells is neither required nor sufficient for leptin's role in reproductive function. Endogenous re-expression of LepRb however, in glutamatergic neurons of the ventral premammilary nucleus (PMV) or ablation of agouti-related protein (AgRP) neurons from leptin signaling-deficient mice are both sufficient to induce puberty and improve fertility. Recent studies have also shown that leptin action in first order GABAergic neurons is required for fertility. Together, these studies begin to delineate key neuronal populations involved in leptin's action in reproduction. In this review, we discuss recent advances made in the field and highlight the questions yet to be answered.
Collapse
Affiliation(s)
- Dhirender V Ratra
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carol F Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
38
|
Bellefontaine N, Elias CF. Minireview: Metabolic control of the reproductive physiology: insights from genetic mouse models. Horm Behav 2014; 66:7-14. [PMID: 24746731 PMCID: PMC4204395 DOI: 10.1016/j.yhbeh.2014.04.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 04/04/2014] [Accepted: 04/08/2014] [Indexed: 12/17/2022]
Abstract
This article is part of a Special Issue Energy Balance. Over the past two decades, and in particular over the past 5-7 years, there has been a tremendous advancement in the understanding of the metabolic control of reproductive physiology. This has been in large part due to the advancement and refinement of gene targeting tools and techniques for molecular mapping. Yet despite the emergence of exciting and often times thought-provoking data through the use of new mouse models, the heavy reliance on gene targeting strategies has become fundamental in this process and thus caution must be exercised when interpreting results. This minireview article will explore the generation of new mouse models using genetic manipulation, such as viral vector delivery and the use of the Cre/loxP system, to investigate the role of circulating metabolic hormones in the coordination of reproductive physiology. In addition, we will also highlight some of the pitfalls in the use of genetic manipulation in the current paradigms. However, it has become clear that metabolic cues employ integrated and plastic neural circuits in order to modulate the neuroendocrine reproductive axis, and despite recent advances much remains to be elucidated about this circuitry.
Collapse
Affiliation(s)
- Nicole Bellefontaine
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carol F Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
39
|
Bellefontaine N, Chachlaki K, Parkash J, Vanacker C, Colledge W, d'Anglemont de Tassigny X, Garthwaite J, Bouret SG, Prevot V. Leptin-dependent neuronal NO signaling in the preoptic hypothalamus facilitates reproduction. J Clin Invest 2014; 124:2550-9. [PMID: 24812663 DOI: 10.1172/jci65928] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 03/20/2014] [Indexed: 01/28/2023] Open
Abstract
The transition to puberty and adult fertility both require a minimum level of energy availability. The adipocyte-derived hormone leptin signals the long-term status of peripheral energy stores and serves as a key metabolic messenger to the neuroendocrine reproductive axis. Humans and mice lacking leptin or its receptor fail to complete puberty and are infertile. Restoration of leptin levels in these individuals promotes sexual maturation, which requires the pulsatile, coordinated delivery of gonadotropin-releasing hormone to the pituitary and the resulting surge of luteinizing hormone (LH); however, the neural circuits that control the leptin-mediated induction of the reproductive axis are not fully understood. Here, we found that leptin coordinated fertility by acting on neurons in the preoptic region of the hypothalamus and inducing the synthesis of the freely diffusible volume-based transmitter NO, through the activation of neuronal NO synthase (nNOS) in these neurons. The deletion of the gene encoding nNOS or its pharmacological inhibition in the preoptic region blunted the stimulatory action of exogenous leptin on LH secretion and prevented the restoration of fertility in leptin-deficient female mice by leptin treatment. Together, these data indicate that leptin plays a central role in regulating the hypothalamo-pituitary-gonadal axis in vivo through the activation of nNOS in neurons of the preoptic region.
Collapse
|
40
|
Furigo IC, Kim KW, Nagaishi VS, Ramos-Lobo AM, de Alencar A, Pedroso JAB, Metzger M, Donato J. Prolactin-sensitive neurons express estrogen receptor-α and depend on sex hormones for normal responsiveness to prolactin. Brain Res 2014; 1566:47-59. [PMID: 24751572 DOI: 10.1016/j.brainres.2014.04.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 04/10/2014] [Accepted: 04/12/2014] [Indexed: 11/26/2022]
Abstract
Estrogens and prolactin share important target tissues, including the gonads, brain, liver, kidneys and some types of cancer cells. Herein, we sought anatomical and functional evidence of possible crosstalk between prolactin and estrogens in the mouse brain. First, we determined the distribution of prolactin-responsive neurons that express the estrogen receptor α (ERα). A large number of prolactin-induced pSTAT5-immunoreactive neurons expressing ERα mRNA were observed in several brain areas, including the anteroventral periventricular nucleus, medial preoptic nucleus, arcuate nucleus of the hypothalamus, ventrolateral subdivision of the ventromedial nucleus of the hypothalamus (VMH), medial nucleus of the amygdala and nucleus of the solitary tract. However, although the medial preoptic area, periventricular nucleus of the hypothalamus, paraventricular nucleus of the hypothalamus, retrochiasmatic area, dorsomedial subdivision of the VMH, lateral hypothalamic area, dorsomedial nucleus of the hypothalamus and ventral premammillary nucleus contained significant numbers of prolactin-responsive neurons, these areas showed very few pSTAT5-immunoreactive cells expressing ERα mRNA. Second, we evaluated prolactin sensitivity in ovariectomized mice and observed that sex hormones are required for a normal responsiveness to prolactin as ovariectomized mice showed a lower number of prolactin-induced pSTAT5 immunoreactive neurons in all analyzed brain nuclei compared to gonad-intact females. In addition, we performed hypothalamic gene expression analyses to determine possible post-ovariectomy changes in components of prolactin signaling. We observed no significant changes in the mRNA expression of prolactin receptor, STAT5a or STAT5b. In summary, sex hormones exert a permissive role in maintaining the brain's prolactin sensitivity, most likely through post-transcriptional mechanisms.
Collapse
Affiliation(s)
- Isadora C Furigo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Ki Woo Kim
- Department of Pharmacology, Institute of Lifestyle Medicine, and Nuclear Receptor Research Consortium, Yonsei University Wonju College of Medicine, Wonju 220-701, Republic of Korea
| | - Vanessa S Nagaishi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Angela M Ramos-Lobo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Amanda de Alencar
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - João A B Pedroso
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Martin Metzger
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Jose Donato
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
| |
Collapse
|
41
|
Nagaishi V, Cardinali L, Zampieri T, Furigo I, Metzger M, Donato J. Possible crosstalk between leptin and prolactin during pregnancy. Neuroscience 2014; 259:71-83. [DOI: 10.1016/j.neuroscience.2013.11.050] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 10/23/2013] [Accepted: 11/22/2013] [Indexed: 11/24/2022]
|
42
|
Chalmers JA, Jang JJ, Belsham DD. Glucose sensing mechanisms in hypothalamic cell models: glucose inhibition of AgRP synthesis and secretion. Mol Cell Endocrinol 2014; 382:262-270. [PMID: 24145125 DOI: 10.1016/j.mce.2013.10.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/23/2013] [Accepted: 10/11/2013] [Indexed: 12/11/2022]
Abstract
Glucose-sensing neurons play a role in energy homeostasis, yet how orexigenic neurons sense glucose remains unclear. As models of glucose-inhibited (GI) neurons, mHypoE-29/1 and mHypoA-NPY/GFP cells express the essential orexigenic neuropeptide AgRP and glucose sensing machinery. Exposure to increasing concentrations of glucose or the glucose analog 2-deoxyglucose (2-DG) results in a decrease in AgRP mRNA levels. Taste receptor, Tas1R2 mRNA expression was reduced by glucose, whereas 2-DG reduced Tas1R3 mRNA levels. Increasing glucose concentrations elicited a rise in Akt and neuronal nitric oxide synthase (nNOS) phosphorylation, CaMKKβ levels, and a reduction of AMP-kinase alpha phosphorylation. Inhibitors of NOS and the cystic fibrosis transmembrane conductance regulator (CFTR) prevented a decrease in AgRP secretion with glucose, suggesting a pivotal role for nNOS and the CFTR in glucose-sensing. These models possess the hallmark characteristics of GI neurons, and can be used to disentangle the mechanisms by which orexigenic neurons sense glucose.
Collapse
Affiliation(s)
- Jennifer A Chalmers
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Janet J Jang
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Denise D Belsham
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Obstetrics and Gynaecology, University of Toronto, Toronto, ON M5S 1A8, Canada; Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5S 1A8, Canada.
| |
Collapse
|
43
|
Pereira VS, Casarotto PC, Hiroaki-Sato VA, Sartim AG, Guimarães FS, Joca SRL. Antidepressant- and anticompulsive-like effects of purinergic receptor blockade: involvement of nitric oxide. Eur Neuropsychopharmacol 2013; 23:1769-78. [PMID: 23434291 DOI: 10.1016/j.euroneuro.2013.01.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 12/27/2012] [Accepted: 01/27/2013] [Indexed: 10/27/2022]
Abstract
Activation of purinergic receptors by ATP (P2R) modulates glutamate release and the activation of post-synaptic P2R is speculated to induce nitric oxide (NO) synthesis. Increased glutamatergic and nitrergic signaling have been involved in the neurobiology of stress-related psychiatric disorders such as anxiety and depression. Therefore, the aim of this study was to test the effects of two P2R antagonists (PPADS and iso-PPADS) in animals submitted to models predictive of antidepressant-, anxiolytic- and anticompulsive-like effects. Swiss mice receiving PPADS at 12.5mg/kg showed reduced immobility time in the forced swimming test (FST) similarly to the prototype antidepressant imipramine (30mg/kg). This dose was also able to decrease the number of buried marbles in the marble-burying test (MBT), an anticompulsive-like effect. However, no effect was observed in animals submitted to the elevated plus maze (EPM) and to the open field test. The systemic administration of iso-PPADS, a preferential P2XR antagonist, also reduced the immobility time in FST, which was associated to a decrease in NOx levels in the prefrontal cortex. In addition, P2X7 receptor was found co-immunoprecipitated with neuronal nitric oxide synthase (NOS1) in the prefrontal cortex. These results suggest that P2X7, possibly coupled to NOS1, could modulate behavioral responses associated to stress-related disorders and it could be a new target for the development of more effective treatments for affective disorders.
Collapse
Affiliation(s)
- Vitor S Pereira
- Department of Pharmacology, School of Medicine, Campus USP, Ribeirão Preto, SP 14049-900, Brazil
| | | | | | | | | | | |
Collapse
|
44
|
Elias CF. A critical view of the use of genetic tools to unveil neural circuits: the case of leptin action in reproduction. Am J Physiol Regul Integr Comp Physiol 2013; 306:R1-9. [PMID: 24196667 DOI: 10.1152/ajpregu.00444.2013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The remarkable development and refinement of the Cre-loxP system coupled with the nonstop production of new mouse models and virus vectors have impelled the growth of various fields of investigation. In this article, I will discuss the data collected using these genetic tools in our area of interest, giving specific emphasis to the identification of the neuronal populations that relay leptin action in reproductive physiology. A series of mouse models that allow manipulation of the leptin receptor gene have been generated. Of those, I will discuss the use of two models of leptin receptor gene reexpression (LepR(neo/neo) and LepR(loxTB/loxTB)) and one model of leptin signaling blockade (LepR(flox/flox)). I will also highlight the differences of using stereotaxic delivery of virus vectors expressing DNA-recombinases (Flp and Cre) and mouse models expressing Cre-recombinase. Our findings indicate that leptin action in the ventral premammillary nucleus is sufficient, but not required, for leptin action in reproduction and that leptin action in Kiss1 neurons arises after pubertal maturation; therefore, direct leptin signaling in Kiss1 neurons is neither required nor sufficient for the permissive action of leptin in pubertal development. It also became evident that the full action of leptin in the reproductive neuroendocrine axis requires the engagement of an integrated circuitry, yet to be fully unveiled.
Collapse
Affiliation(s)
- Carol F Elias
- Department of Molecular and Integrative Physiology and Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan
| |
Collapse
|
45
|
Sharma S, Morinaga H, Hwang V, Fan W, Fernandez MO, Varki N, Olefsky JM, Webster NJG. Free fatty acids induce Lhb mRNA but suppress Fshb mRNA in pituitary LβT2 gonadotropes and diet-induced obesity reduces FSH levels in male mice and disrupts the proestrous LH/FSH surge in female mice. Endocrinology 2013; 154:2188-99. [PMID: 23525221 PMCID: PMC3740488 DOI: 10.1210/en.2012-2218] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Female obesity is associated with insulin resistance, hyperandrogenemia, and reproductive dysfunction. We hypothesized that elevated free fatty acids (FFAs) might directly modulate pituitary gonadotropin production. FFAs caused a time- and dose-dependent increase in phosphorylation of the MAPKs p38MAPK, c-Jun N-terminal kinase (JNK)-1/2, and ERK1/2 in LβT2 gonadotrope cells. Furthermore, FFAs up-regulated Lhb mRNA expression acutely, an effect that was blocked by JNK inhibition, but suppressed Fshb mRNA expression, an effect that was independent of MAPK signaling. FFAs enhanced the activation of the MAPKs in the presence of GnRH, although the cotreatment did not alter Lhb induction but did eliminate the GnRH induction of Fshb. FFAs also suppressed activin-induced Fshb expression. Knockdown experiments showed that the FFA effect on the inflammatory kinases p38MAPK and JNK and on Lhb, but not Fshb, mRNA expression is mediated via toll-like receptor-2 and toll-like receptor-4 and was mimicked by lipopolysaccharide stimulation. In vivo, male C57BL/6 mice on a high-fat diet showed reduced FSH levels consistent with the suppression of Fshb seen in vitro. Histological analysis of the testes showed an increased number of abnormal seminiferous tubules. Female mice on a high-fat diet lacked the expected proestrus LH and FSH surge and exhibited an increase in the number of days at estrus and a reduced number of days at proestrus, and ovaries had significantly fewer corpora lutea. Taken together, our findings suggest that lipid excess can lead to reproductive defects in both male and female mice.
Collapse
MESH Headings
- Animals
- Diet, High-Fat/adverse effects
- Dose-Response Relationship, Drug
- Fatty Acids, Nonesterified/pharmacology
- Female
- Follicle Stimulating Hormone, beta Subunit/blood
- Follicle Stimulating Hormone, beta Subunit/genetics
- Follicle Stimulating Hormone, beta Subunit/metabolism
- Gene Expression/drug effects
- Gonadotrophs/cytology
- Gonadotrophs/drug effects
- Gonadotrophs/metabolism
- Immunoblotting
- Luteinizing Hormone, beta Subunit/blood
- Luteinizing Hormone, beta Subunit/genetics
- Luteinizing Hormone, beta Subunit/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mitogen-Activated Protein Kinases/metabolism
- Obesity/etiology
- Obesity/genetics
- Obesity/metabolism
- Ovary/drug effects
- Ovary/metabolism
- Pituitary Gland/cytology
- Proestrus/drug effects
- Proestrus/genetics
- Proestrus/metabolism
- RNA Interference
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Toll-Like Receptor 2/genetics
- Toll-Like Receptor 2/metabolism
- Toll-Like Receptor 4/genetics
- Toll-Like Receptor 4/metabolism
Collapse
Affiliation(s)
- Shweta Sharma
- Medical Research Service, Veterans Affairs San Diego Healthcare System, San Diego California 92161, USA
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Groessl F, Jeong JH, Talmage DA, Role LW, Jo YH. Overnight fasting regulates inhibitory tone to cholinergic neurons of the dorsomedial nucleus of the hypothalamus. PLoS One 2013; 8:e60828. [PMID: 23585854 PMCID: PMC3621823 DOI: 10.1371/journal.pone.0060828] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 03/03/2013] [Indexed: 11/19/2022] Open
Abstract
The dorsomedial nucleus of the hypothalamus (DMH) contributes to the regulation of overall energy homeostasis by modulating energy intake as well as energy expenditure. Despite the importance of the DMH in the control of energy balance, DMH-specific genetic markers or neuronal subtypes are poorly defined. Here we demonstrate the presence of cholinergic neurons in the DMH using genetically modified mice that express enhanced green florescent protein (eGFP) selectively in choline acetyltransferase (Chat)-neurons. Overnight food deprivation increases the activity of DMH cholinergic neurons, as shown by induction of fos protein and a significant shift in the baseline resting membrane potential. DMH cholinergic neurons receive both glutamatergic and GABAergic synaptic input, but the activation of these neurons by an overnight fast is due entirely to decreased inhibitory tone. The decreased inhibition is associated with decreased frequency and amplitude of GABAergic synaptic currents in the cholinergic DMH neurons, while glutamatergic synaptic transmission is not altered. As neither the frequency nor amplitude of miniature GABAergic or glutamatergic postsynaptic currents is affected by overnight food deprivation, the fasting-induced decrease in inhibitory tone to cholinergic neurons is dependent on superthreshold activity of GABAergic inputs. This study reveals that cholinergic neurons in the DMH readily sense the availability of nutrients and respond to overnight fasting via decreased GABAergic inhibitory tone. As such, altered synaptic as well as neuronal activity of DMH cholinergic neurons may play a critical role in the regulation of overall energy homeostasis.
Collapse
Affiliation(s)
- Florian Groessl
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, New York, United States of America
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter, Vienna, Vienna, Austria
| | - Jae Hoon Jeong
- Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York, United States of America
| | - David A. Talmage
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, New York, United States of America
| | - Lorna W. Role
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, New York, United States of America
| | - Young-Hwan Jo
- Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York, United States of America
- * E-mail:
| |
Collapse
|
47
|
Donato J, Lee C, Ratra DV, Franci CR, Canteras NS, Elias CF. Lesions of the ventral premammillary nucleus disrupt the dynamic changes in Kiss1 and GnRH expression characteristic of the proestrus-estrus transition. Neuroscience 2013; 241:67-79. [PMID: 23518222 DOI: 10.1016/j.neuroscience.2013.03.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 02/20/2013] [Accepted: 03/08/2013] [Indexed: 11/16/2022]
Abstract
We have recently demonstrated that the ventral premammillary nucleus (PMV) plays a key role in the metabolic control of the female reproductive axis. However, whether PMV neurons modulate the reproductive neural circuitry and/or the expression of sexual behaviors has not been determined. Here, we showed that the expression of estrogen and progesterone receptors in the PMV is modulated by changing levels of sex steroids across the estrous cycle. We also showed that sexual behavior, not the high physiologic levels of sex steroids, induces Fos in PMV neurons. Bilateral lesions of the PMV caused no significant changes in proceptive behavior but a high percentage of PMV-lesioned rats failed to exhibit lordosis behavior when exposed to a sexually experienced male rat (50% vs. 18% in the control group). Notably, lesions of the PMV disrupted the physiologic fluctuations of Kiss1 and GnRH mRNA expression characteristic of the proestrus-to-estrus transition. This neurochemical imbalance may ultimately alter female reproductive behavior. Our findings suggest that the PMV is a component of the neural circuitry that modulates the physiologic fluctuations of key neuroendocrine players (i.e., Kiss1 and GnRH) in the control of the female reproductive physiology.
Collapse
Affiliation(s)
- J Donato
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | | | | | | | | |
Collapse
|
48
|
Elias CF, Purohit D. Leptin signaling and circuits in puberty and fertility. Cell Mol Life Sci 2012; 70:841-62. [PMID: 22851226 PMCID: PMC3568469 DOI: 10.1007/s00018-012-1095-1] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/05/2012] [Accepted: 07/09/2012] [Indexed: 12/22/2022]
Abstract
Leptin is an adipocyte-derived hormone involved in a myriad of physiological process, including the control of energy balance and several neuroendocrine axes. Leptin-deficient mice and humans are obese, diabetic, and display a series of neuroendocrine and autonomic abnormalities. These individuals are infertile due to a lack of appropriate pubertal development and inadequate synthesis and secretion of gonadotropins and gonadal steroids. Leptin receptors are expressed in many organs and tissues, including those related to the control of reproductive physiology (e.g., the hypothalamus, pituitary gland, and gonads). In the last decade, it has become clear that leptin receptors located in the brain are major players in most leptin actions, including reproduction. Moreover, the recent development of molecular techniques for brain mapping and the use of genetically modified mouse models have generated crucial new findings for understanding leptin physiology and the metabolic influences on reproductive health. In the present review, we will highlight the new advances in the field, discuss the apparent contradictions, and underline the relevance of this complex physiological system to human health. We will focus our review on the hypothalamic circuitry and potential signaling pathways relevant to leptin’s effects in reproductive control, which have been identified with the use of cutting-edge technologies of molecular mapping and conditional knockouts.
Collapse
Affiliation(s)
- Carol F Elias
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Y6-220B, Dallas, TX, 75390-9077, USA.
| | | |
Collapse
|
49
|
Leptin action through hypothalamic nitric oxide synthase-1-expressing neurons controls energy balance. Nat Med 2012; 18:820-3. [PMID: 22522563 PMCID: PMC3531967 DOI: 10.1038/nm.2724] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 03/09/2012] [Indexed: 11/18/2022]
Abstract
Few effective measures exist to combat the worldwide obesity epidemic1, and the identification of potential therapeutic targets requires a deeper understanding of the mechanisms that control energy balance. Leptin, an adipocyte hormone that signals the status of cellular energy stores, acts via multiple types of leptin receptor (LepR-b)-expressing neurons in the brain to control feeding, energy expenditure and endocrine function2–4. The modest contributions to energy balance attributable to leptin action via many previously-studied LepR-b populations5–9 suggest that other, heretofore unidentified, hypothalamic LepR-b neurons play important roles. Here, we examine the role of LepR-b in neuronal nitric oxide synthase (NOS1)-expressing (LepR-bNOS1) neurons that comprise approximately 20% of hypothalamic LepR-b neurons. Nos1cre-mediated ablation of LepR-b (LeprNOS1KO mice) produces hyperphagic obesity, decreased energy expenditure and hyperglycemia approaching that of LepR-b-null mice. In contrast, endocrine functions in LeprNOS1KO mice are relatively spared. Thus, hypothalamic LepR-bNOS1 neurons are essential for the control of energy balance by leptin.
Collapse
|
50
|
Elias CF. Leptin action in pubertal development: recent advances and unanswered questions. Trends Endocrinol Metab 2012; 23:9-15. [PMID: 21978495 PMCID: PMC3251729 DOI: 10.1016/j.tem.2011.09.002] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 09/01/2011] [Accepted: 09/08/2011] [Indexed: 11/18/2022]
Abstract
In recent years we have witnessed a considerable advance in the understanding of the processes involved in pubertal development. This is partially due to the discovery of the kisspeptin system and its fundamental role in the control of reproductive physiology. In addition, the suspected relationship between increasing rates of childhood obesity and the apparent reduction in the age of puberty onset in girls has generated a growing interest in identifying the mechanisms by which nutrition may influence reproductive maturation. This review will focus on recent data unveiling the sites of leptin action in pubertal development that were generated using novel molecular techniques and genetically engineered mouse models. It will also emphasize areas of contention and the many relevant questions that remain unanswered.
Collapse
Affiliation(s)
- Carol F Elias
- Department of Internal Medicine, Division of Hypothalamic Research and Green Center for Reproductive Biology Sciences, University of Texas Southwestern (UTSW) Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|