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Iwata K, Ogata R, Sato M, Matsuda F, Ishii H, Ozawa H. Short-term depletion of plasma estrogen affects hypothalamic kisspeptin-neurokinin B-dynorphin A neurons, gonadotrophs, and pulsatile luteinizing hormone secretion in female rats. Peptides 2023; 160:170929. [PMID: 36574861 DOI: 10.1016/j.peptides.2022.170929] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/04/2022] [Accepted: 12/23/2022] [Indexed: 12/25/2022]
Abstract
Kisspeptin-neurokinin B-dynorphin A (KNDy) neurons in the arcuate nucleus (ARC) regulate pulsatile luteinizing hormone (LH) secretion. These neurons express estrogen receptors and are negatively regulated by estrogen. This study aimed to determine whether estrogen supplementation after short-term ovariectomy-induced estrogen depletion has different effects on KNDy neurons depending on the timing of the supplementation. To decrease endogenous estradiol (E2) for a short time, adult female rats received a tube filled with E2 one week after ovariectomy and utilized it one week later (O1w + E). From the results of immunohistochemistry, the response to E2 was attenuated in KNDy neurons of O1w + E rats. Enlarged LH-secreting cells in the anterior pituitary were found in O1w + E rats; however, such enlarged LH cells were not found in ones without previous short-term E2 depletion. From the analysis of LH pulses, plasma LH levels were increased in O1w + E rats relative to ones without previous short-term E2 depletion. These results suggested that once endogenous sex steroids were depleted, the response to E2 in hypothalamic KNDy neurons did not fully recover in one week. Thus, short-term sex steroid depletion due to gonadectomy could alter the response to the sex steroids in KNDy neurons even though the period without sex steroids is only one week, and the alteration is likely to affect plasma hormone levels.
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Affiliation(s)
- Kinuyo Iwata
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8602, Japan.
| | - Risako Ogata
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8602, Japan
| | - Marimo Sato
- Department of Veterinary Medical Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Fuko Matsuda
- Department of Veterinary Medical Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Hirotaka Ishii
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8602, Japan
| | - Hitoshi Ozawa
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8602, Japan; Faculty of Health Science, Bukkyo Univeristy, Kyoto, 604-8418, Japan
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Enomoto H, Iwata K, Matsumoto K, Otsuka M, Morita A, Ozawa H. Hypothalamic KNDy neuron expression in streptozotocin-induced diabetic female rats. J Endocrinol 2022; 253:39-51. [PMID: 35084363 PMCID: PMC8942341 DOI: 10.1530/joe-21-0169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 01/27/2022] [Indexed: 11/08/2022]
Abstract
Kisspeptin neurons, i.e. KNDy neurons, in the arcuate nucleus (ARC) coexpress neurokinin B and dynorphin and regulate gonadotropin-releasing hormone/luteinizing hormone (LH) pulses. Because it remains unclear whether these neurons are associated with reproductive dysfunction in diabetic females, we examined the expression of KNDy neurons detected by histochemistry in streptozotocin (STZ)-induced diabetic female rats 8 weeks after STZ injection. We also evaluated relevant metabolic parameters - glucose, 3-hydroxybutyrate, and non-esterified fatty acids - as indicators of diabetes progression. Severe diabetes with hyperglycemia and severe ketosis suppressed the mRNA expression of KNDy neurons, resulting in low plasma LH levels and persistent diestrus. In moderate diabetes with hyperglycemia and moderate ketosis, kisspeptin-immunoreactive cells and plasma LH levels were decreased, while the mRNA expression of KNDy neurons remained unchanged. Mild diabetes with hyperglycemia and slight ketosis did not affect KNDy neurons and plasma LH levels. The number of KNDy cells was strongly and negatively correlated with plasma 3-hydroxybutyrate levels. The vaginal smear analysis showed unclear proestrus in diabetic rats 3-5 days after STZ injection, and the mRNA expression of kisspeptin in the ARC was decreased 2 weeks after STZ injection in severely diabetic rats. Kisspeptin neurons in the anteroventral periventricular nucleus (AVPV), which induce an LH surge, were unaffected at 2 and 8 weeks after STZ injection regardless of the diabetes severity. These results suggest that diabetes mellitus progression in females may negatively affect ARC kisspeptin neurons but not AVPV kisspeptin neurons, implicating a potential role of ARC kisspeptin neurons in menstrual disorder and infertility.
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Affiliation(s)
- Hiroyuki Enomoto
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
- Department of Neurosurgery, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
| | - Kinuyo Iwata
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
- Correspondence should be addressed to K Iwata:
| | - Keisuke Matsumoto
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
| | - Mai Otsuka
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
| | - Akio Morita
- Department of Neurosurgery, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
| | - Hitoshi Ozawa
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo, Japan
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Ozawa H. Kisspeptin neurons as an integration center of reproductive regulation: Observation of reproductive function based on a new concept of reproductive regulatory nervous system. Reprod Med Biol 2021; 21:e12419. [PMID: 34934400 PMCID: PMC8656200 DOI: 10.1002/rmb2.12419] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 09/20/2021] [Accepted: 09/24/2021] [Indexed: 11/29/2022] Open
Abstract
Background Regulation of the reproductive system has been explained by the actions and feedback of gonadotropin releasing hormone‐luteinizing hormone/follicle stimulating hormone (GnRH‐LH/FSH) ‐sex steroids; however, the discovery of kisspeptin neurons and a kisspeptin‐GnRH‐LH/FSH axis has prompted this regulation to be reviewed. Methods We investigated changes in kisspeptin neurons and associated changes in the hypothalamic‐pituitary‐gonadal (HPG) axis under various situations and experimental conditions using histochemical methods. Main findings (Results) Kisspeptin neurons play an important role in receiving and integrating information from internal and external environmental factors and communicating it to the conventional HPG axis. Conclusion The recently described Kisspeptin‐GnRH‐LH/FSH‐gonad system regulates reproductive function via mechanisms that until recently were not completely understood.
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Affiliation(s)
- Hitoshi Ozawa
- Department of Anatomy and Neurobiology Graduate School of Medicine Nippon Medical School Tokyo Japan
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Minabe S, Iwata K, Tsuchida H, Tsukamura H, Ozawa H. Effect of diet-induced obesity on kisspeptin-neurokinin B-dynorphin A neurons in the arcuate nucleus and luteinizing hormone secretion in sex hormone-primed male and female rats. Peptides 2021; 142:170546. [PMID: 33794282 DOI: 10.1016/j.peptides.2021.170546] [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: 12/28/2020] [Revised: 03/13/2021] [Accepted: 03/24/2021] [Indexed: 12/16/2022]
Abstract
Metabolic stress resulting from either lack or excess of nutrients often causes infertility in both sexes. Kisspeptin-neurokinin B-dynorphin A (KNDy) neurons in the arcuate nucleus (ARC) has been suggested to be a key players in reproduction via direct stimulation of the pulsatile gonadotropin-releasing hormone (GnRH) and subsequent gonadotropin release in mammalian species. In this study, we investigated the effect of high-fat diet (HFD) on hypothalamic KNDy gene expression to examine the pathogenic mechanism underlying obesity-induced infertility in male and female rats. Male and female rats at 7 weeks of age were fed with either a standard or HFD for 4 months. In the male rats, the HFD caused a significant suppression of ARC Kiss1 and Pdyn gene expressions, but did not affect the plasma luteinizing hormone (LH) levels and sizes of the morphology of the testis and epididymis. In the female rats, 58% of the HFD-fed female rats exhibited irregular estrous cycles, whereas the remaining rats showed regular cycles. Two of the 10 rats that showed HFD-induced irregular estrous cycles showed profound suppression of LH pulse frequency and the number of ARC Kiss1-expressing cells, whereas the other females showed normal LH pulses and ARC Kiss1 expression. Our finding shows that suppression of ARC Kiss1 expression might be the initial pathological change of hypogonadotropic hypogonadism in HFD-fed male rats, while the obese-related infertility in the female rats may be mainly induced by KNDy-independent pathways. Taken together, ARC kisspeptin neurons in male rats may be susceptible to HFD-induced obesity compared with those in female rats.
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Affiliation(s)
- Shiori Minabe
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, 113- 8602, Japan.
| | - Kinuyo Iwata
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, 113- 8602, Japan
| | - Hitomi Tsuchida
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 464-8601, Japan
| | - Hiroko Tsukamura
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 464-8601, Japan
| | - Hitoshi Ozawa
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, 113- 8602, Japan
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Vasiliev G, Chadaeva I, Rasskazov D, Ponomarenko P, Sharypova E, Drachkova I, Bogomolov A, Savinkova L, Ponomarenko M, Kolchanov N, Osadchuk A, Oshchepkov D, Osadchuk L. A Bioinformatics Model of Human Diseases on the Basis of Differentially Expressed Genes (of Domestic Versus Wild Animals) That Are Orthologs of Human Genes Associated with Reproductive-Potential Changes. Int J Mol Sci 2021; 22:2346. [PMID: 33652917 PMCID: PMC7956675 DOI: 10.3390/ijms22052346] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/13/2021] [Accepted: 02/23/2021] [Indexed: 12/18/2022] Open
Abstract
Earlier, after our bioinformatic analysis of single-nucleotide polymorphisms of TATA-binding protein-binding sites within gene promoters on the human Y chromosome, we suggested that human reproductive potential diminishes during self-domestication. Here, we implemented bioinformatics models of human diseases using animal in vivo genome-wide RNA-Seq data to compare the effect of co-directed changes in the expression of orthologous genes on human reproductive potential and during the divergence of domestic and wild animals from their nearest common ancestor (NCA). For example, serotonin receptor 3A (HTR3A) deficiency contributes to sudden death in pregnancy, consistently with Htr3a underexpression in guinea pigs (Cavia porcellus) during their divergence from their NCA with cavy (C. aperea). Overall, 25 and three differentially expressed genes (hereinafter, DEGs) in domestic animals versus 11 and 17 DEGs in wild animals show the direction consistent with human orthologous gene-markers of reduced and increased reproductive potential. This indicates a reliable association between DEGs in domestic animals and human orthologous genes reducing reproductive potential (Pearson's χ2 test p < 0.001, Fisher's exact test p < 0.05, binomial distribution p < 0.0001), whereas DEGs in wild animals uniformly match human orthologous genes decreasing and increasing human reproductive potential (p > 0.1; binomial distribution), thus enforcing the norm (wild type).
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Affiliation(s)
- Gennady Vasiliev
- Novosibirsk State University, 630090 Novosibirsk, Russia;
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Irina Chadaeva
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Dmitry Rasskazov
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Petr Ponomarenko
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Ekaterina Sharypova
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Irina Drachkova
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Anton Bogomolov
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Ludmila Savinkova
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Mikhail Ponomarenko
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Nikolay Kolchanov
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Alexander Osadchuk
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Dmitry Oshchepkov
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
| | - Ludmila Osadchuk
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (I.C.); (D.R.); (P.P.); (E.S.); (I.D.); (A.B.); (L.S.); (N.K.); (A.O.); (D.O.); (L.O.)
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Ziarniak K, Kołodziejski PA, Pruszyńska-Oszmałek E, Dudek M, Kalló I, Sliwowska JH. Effects of Ovariectomy and Sex Hormone Replacement on Numbers of Kisspeptin-, Neurokinin B- and Dynorphin A-immunoreactive Neurons in the Arcuate Nucleus of the Hypothalamus in Obese and Diabetic Rats. Neuroscience 2020; 451:184-196. [PMID: 33065232 DOI: 10.1016/j.neuroscience.2020.10.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/17/2020] [Accepted: 10/02/2020] [Indexed: 10/23/2022]
Abstract
KNDy neurons co-expressing kisspeptin (KP), neurokinin B (NKB) and dynorphin A (DYN A) in the arcuate nucleus of the hypothalamus (ARC) are key regulators of reproduction. Their activity is influenced by metabolic and hormonal signals. Previously, we have shown that orchidectomy alters the KP-, NKB-, and DYN A-immunoreactivity in the high-fat diet-induced (HFD) obesity and diabetes type 2 (DM2) models. Considering the potential sex difference in the response of KNDy neurons, we have hypothesized that ovariectomy (OVX) and post-ovariectomy replacement with estradiol (OVX+E2) or estradiol and progesterone (OVX+E2+P4) will also affect these neurons in HFD and DM2 females. Thus, each of these treatment protocols were employed for control, HFD, and DM2 groups of rats leading to nine experimental conditions within which we have determined the number of KP-, NKB-, or DYN-immunoreactive (-ir) neurons and assessed the metabolic and hormonal profiles of the animals. Accordingly: (1) no effects of group and surgery were observed on the number of KP-ir neurons; (2) the overall number of NKB-ir neurons was higher in the OVX+E2+P4 and OVX+E2 animals compared to OVX; (3) overall, the number of DYN A-ir neurons was higher in DM2 vs. control group, and surgery had an effect on the number of DYN A-ir neurons; (4) the metabolic and hormonal profiles were altered in HFD and DM2 animals compared to controls. Current data together with our previously published results indicate sex-specific differences in the response of KNDy neurons to DM2.
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Affiliation(s)
- Kamil Ziarniak
- Laboratory of Neurobiology, Faculty of Veterinary Medicine and Animal Science, Poznan University of Life Sciences, Wojska Polskiego 71C, 60-625 Poznan, Poland.
| | - Paweł A Kołodziejski
- Department of Animal Physiology, Biochemistry and Biostructure, Faculty of Veterinary Medicine and Animal Science, Poznan University of Life Sciences, Wolynska 35, 60-637 Poznan, Poland.
| | - Ewa Pruszyńska-Oszmałek
- Department of Animal Physiology, Biochemistry and Biostructure, Faculty of Veterinary Medicine and Animal Science, Poznan University of Life Sciences, Wolynska 35, 60-637 Poznan, Poland.
| | - Monika Dudek
- Laboratory of Neurobiology, Faculty of Veterinary Medicine and Animal Science, Poznan University of Life Sciences, Wojska Polskiego 71C, 60-625 Poznan, Poland.
| | - Imre Kalló
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Budapest, 1083, Szigony u. 43, Hungary.
| | - Joanna H Sliwowska
- Laboratory of Neurobiology, Faculty of Veterinary Medicine and Animal Science, Poznan University of Life Sciences, Wojska Polskiego 71C, 60-625 Poznan, Poland.
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Abstract
This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY, 11367, United States.
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8
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Iwata K, Kunimura Y, Ozawa H. Hypothalamic Kisspeptin Expression in Hyperandrogenic Female Rats and Aging Rats. Acta Histochem Cytochem 2019; 52:85-91. [PMID: 31777408 PMCID: PMC6872488 DOI: 10.1267/ahc.19013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/05/2019] [Indexed: 01/29/2023] Open
Abstract
Hypothalamic kisspeptin neurons stimulate gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) release. Kisspeptin neurons in the anteroventral periventricular nucleus (AVPV) of rats induce an LH surge for ovulation, and those in the arcuate nucleus (ARC) regulate pulsatile LH secretion for follicle development and spermatogenesis. Dysfunction of kisspeptin neurons thus reduces the reproductive function. This review focuses on the effect of androgen or aging on kisspeptin expression in rats. Although androgen directly suppresses ARC kisspeptin neurons in female rats, the AVPV kisspeptin neurons are hardly affected. In rats, plasma LH concentrations decrease in both sexes with aging, and ARC kisspeptin expression also decreases in old rats compared with young rats. In addition, kisspeptin neurons may be associated with hyperprolactinemia in old female rats because they are known to release prolactin through hypothalamic tuberoinfundibular dopaminergic (TIDA) neurons. Hypothalamic kisspeptin neurons are thus the main regulator to secrete LH, and inhibition of kisspeptin expression leads to various kinds of reproductive dysfunction.
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Affiliation(s)
- Kinuyo Iwata
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School
| | - Yuyu Kunimura
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School
| | - Hitoshi Ozawa
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School
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9
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Moore AM, Coolen LM, Lehman MN. Kisspeptin/Neurokinin B/Dynorphin (KNDy) cells as integrators of diverse internal and external cues: evidence from viral-based monosynaptic tract-tracing in mice. Sci Rep 2019; 9:14768. [PMID: 31611573 PMCID: PMC6791851 DOI: 10.1038/s41598-019-51201-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 09/25/2019] [Indexed: 02/01/2023] Open
Abstract
Neurons in the hypothalamic arcuate nucleus (ARC) that co-express kisspeptin, neurokinin B and dynorphin (KNDy cells) are essential for mammalian reproduction as key regulators of gonadotropin-releasing hormone (GnRH) secretion. Although multiple endogenous and exogenous signals act indirectly via KNDy neurons to regulate GnRH, the identity of upstream neurons that provide synaptic input to this subpopulation is unclear. We used rabies-mediated tract-tracing in transgenic Kiss1-Cre mice combined with whole-brain optical clearing and multiple-label immunofluorescence to create a comprehensive and quantitative brain-wide map of neurons providing monosynaptic input to KNDy cells, as well as identify the estrogen receptor content and peptidergic phenotype of afferents. Over 90% of monosynaptic input to KNDy neurons originated from hypothalamic nuclei in both male and female mice. The greatest input arose from non-KNDy ARC neurons, including proopiomelanocortin-expressing cells. Significant female-dominant sex differences in afferent input were detected from estrogen-sensitive hypothalamic nuclei critical for reproductive endocrine function and sexual behavior in mice, indicating KNDy cells may provide a unique site for the coordination of sex-specific behavior and gonadotropin release. These data provide key insight into the structural framework underlying the ability of KNDy neurons to integrate endogenous and environmental signals important for the regulation of reproductive function.
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Affiliation(s)
- Aleisha M Moore
- Brain Health Research Institute and Dept. of Biological Sciences, Kent State University, Kent, OH, USA.
| | - Lique M Coolen
- Brain Health Research Institute and Dept. of Biological Sciences, Kent State University, Kent, OH, USA
| | - Michael N Lehman
- Brain Health Research Institute and Dept. of Biological Sciences, Kent State University, Kent, OH, USA
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10
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Alotaibi MF. Physiology of puberty in boys and girls and pathological disorders affecting its onset. J Adolesc 2019; 71:63-71. [PMID: 30639665 DOI: 10.1016/j.adolescence.2018.12.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/26/2018] [Accepted: 12/28/2018] [Indexed: 12/18/2022]
Abstract
Puberty is a physiological event involving the attainment of reproductive capability and complete development of sexual and physical organs. Changing from childhood to adulthood is a complex process and is tightly controlled by interconnection pathways at the level of the hypothalamus which can be influenced by environmental, psychosocial, and endocrine factors. Although various mechanisms underlying the onset of normal puberty have been investigated in humans and animals, the exact molecular mechanisms thereof remain unclear. The aim of this review is to summarize the current state of knowledge and provide a synoptic overview about the physiology of puberty in adolescent boys and girls, and describe pathological disorders affecting its onset.
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Affiliation(s)
- Mohammed F Alotaibi
- Department of Physiology, College of Medicine, King Saud University and King Khalid University Hospital, P.O Box 2925, Riyadh, 11461, Saudi Arabia.
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11
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Moon KH, Park SY, Kim YW. Obesity and Erectile Dysfunction: From Bench to Clinical Implication. World J Mens Health 2018; 37:138-147. [PMID: 30079640 PMCID: PMC6479091 DOI: 10.5534/wjmh.180026] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/17/2018] [Accepted: 05/23/2018] [Indexed: 12/25/2022] Open
Abstract
Obesity is a major public health issue worldwide and is frequently associated with erectile dysfunction (ED). Both conditions may share an internal pathologic environment, also known as common soil. Their main pathophysiologic processes are oxidative stress, inflammation, and resultant insulin and leptin resistance. Moreover, the severity of ED is correlated with comorbid medical conditions, including obesity. Therefore, amelioration of these comorbidities may increase the efficacy of ED treatment with phosphodiesterase 5 inhibitors, the first-line medication for patients with ED. Although metformin was originally developed as an insulin sensitizer six decades ago, it has also been shown to improve leptin resistance. In addition, metformin has been reported to reduce oxidative stress, inflammatory response, and body weight, as well as improve ED, in animal and human studies. Moreover, administration of a combination of metformin and phosphodiesterase 5 inhibitors improves erectile function in patients with ED who have a poor response to sildenafil and are insulin resistant. Thus, concomitant treatment of metabolic derangements associated with obesity in patients with ED who are obese would improve the efficacy and reduce the refractory response to penile vasodilators. In this review, we discuss the connecting factors between obesity and ED and the possible combined treatment modalities.
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Affiliation(s)
- Ki Hak Moon
- Department of Urology, Yeungnam University College of Medicine, Daegu, Korea
| | - So Young Park
- Department of Physiology, Yeungnam University College of Medicine, Daegu, Korea
| | - Yong Woon Kim
- Department of Physiology, Yeungnam University College of Medicine, Daegu, Korea.
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